Split (1)

train · 150k rows

file stringlengths 27 28	text stringlengths 1 5.17M
PMC009xxxxxx/PMC9449270.txt	==== Front Child Youth Care Forum Child Youth Care Forum Child & Youth Care Forum 1053-1890 1573-3319 Springer US New York 36092528 9711 10.1007/s10566-022-09711-y Original Paper Youth Development Staff Experiences During the COVID-19 Pandemic: a Mixed Methods Study http://orcid.org/0000-0002-5217-0461 Woodberry-Shaw Debralyn [email protected] 1 Akiva Thomas 1 Lewis Stephanie S. 2 1 grid.21925.3d 0000 0004 1936 9000 School of Education, University of Pittsburgh, Pittsburgh, USA 2 Allegheny Partners for Out-of-School Time, Pittsburgh, USA 7 9 2022 2023 52 4 829853 24 1 2022 27 6 2022 16 8 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Background Youth-serving organizations in the United States provide programs, activities, and opportunities for young people before school, during school, after school, in summer, and on weekends. At the core of youth-serving organizations are the adults; that is, youth development staff. Objective In this explanatory sequential mixed methods study we explored youth development staff’s stress and worries, their compassion satisfaction, and whether stress and compassion satisfaction varied by race/ethnicity and gender during the early months of the COVID-19 pandemic – a collective trauma event. Methods We surveyed 283 youth development staff and interviewed a subset of 25. Results Results suggest that youth development staff experienced stress and compassion satisfaction during the COVID-19 pandemic. Conclusion We recommend organizational leaders provide youth development staff with support before a collective trauma event. They can work to change, add, or remove policies, practices, and routines to help decrease stress and increase compassion satisfaction. In addition, based on our results from this study our primary recommendation specific to collective trauma events, after taking care of their own personal wellness, is for youth development staff to focus on what is in their control and work to do those things for as many young people as they can. Keywords COVID-19 Youth development staff Stress Compassion satisfaction Collective trauma http://dx.doi.org/10.13039/100000934 Heinz Endowments Heinz Endowments Woodberry-Shaw Debralyn issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcYouth-serving organizations in the United States provide programs, activities, and opportunities for young people before school, during school, after school, in summer, and on weekends (LeMenestrel & Lauxman, 2011).1 One of the most significant components of youth-serving organizations are the adults; that is, youth development staff.2 Youth development staff work to support young people – some primarily work with them directly and others have management and executive roles (Akiva et al., 2020). Through this study, we sought to understand the experience of youth development staff during the first two months of the COVID-19 pandemic – a collective trauma event. When school buildings closed in the early spring of 2020, young people needed safe spaces with adults while they attended online classes and completed homework assignments. Youth-serving organizations, being a part of the learning ecosystem (Akiva et al., 2021; Hecht & Crowley, 2020), stepped in to serve as those spaces for many young people. Youth development staff aided young people not only with their academic work, but also provided meals, snacks, and other supports. This mixed methods research focused on youth development staff and their experiences in this role. Specifically, we explored youth development staff’s stress and worries, their compassion satisfaction, and whether stress and compassion satisfaction varied by race/ethnicity,3 and gender. Youth-Serving Organizations Youth-serving organizations play an important role in the lives of many young people. Their focus is wide ranging, including topics such as civic engagement, arts, workforce development, mentoring, STEM (science, technology, engineering, and math), and tutoring (Morrison, 2014; Vance, 2010). America After 3PM, a report from Afterschool Alliance (2020), notes that parents report that afterschool programs provide peace of mind about their children while they are working (83% of parents) and that, in many cases, afterschool programs allow working parents to keep their jobs (81%). In addition, young people who participate in youth programs can gain knowledge and skills in areas such as self-expression, exploration of interests, social justice, critical consciousness, and development and appreciation of social identities including racial identity (Carey et al., 2020; Halpern, 2003; Ladson-Billings, 2014; McLaughlin & Irby, 1994; The National Child Traumatic Stress Network, 2017). Youth Development Staff and Professional Quality of Life Youth development staff and the relationships they develop with young people are widely seen as key elements in youth-serving organizations (McLaughlin et al., 1994). In America After 3PM, 77% of parents responded that they believed afterschool programs facilitate positive relationships between young people and caring adults (Afterschool Alliance, 2020). Li & Julian (2012) argue that the relationships youth development staff have with young people are the “active ingredient” in youth programs and essential to young people’s development. Relationships provide young people the opportunity to “define who they are, what they can become, and how and why they are important to other people” (National Scientific Council on the Developing Child, 2009, p. 1). Although positive adult relationships are important to young people, the stress that youth development staff experience can be a barrier to building and maintaining those relationships (Osher et al.,2020; Sandilos et al., 2018). Given their important roles in young people’s lives, research about youth development staff is surprisingly sparse. However, related research from other human-serving professions such as K-12 in-school education, social work, and the medical field (Jaracz et al., 2017; White et al., 2020) can be informative. Stamm (2010) describes “professional quality of life” as the combination of both the positives of the helping job (compassion satisfaction) and the negatives (compassion fatigue), which is broken down into burnout and secondary traumatic stress. Compassion Satisfaction According to Locke (1969), “job satisfaction is the pleasurable emotional state resulting from the appraisal of one’s job as achieving or facilitating the achievement of one’s job values” (p. 316). Compassion satisfaction, in this case a component or form of job satisfaction, is specific to the helping fields. It is how pleased or fulfilled an individual is with their job whether it is the actual work being done, their colleagues, or the work environment (Stamm, 2010). Youth development staff in one study reported higher levels of job satisfaction (80% satisfied or very satisfied) than individuals in other occupations (64% satisfied or very satisfied; Yohalem et al., 2006). Compassion Fatigue According to Stamm (2010), compassion fatigue is the other component of a youth development staff’s professional quality of life and consists of burnout and secondary traumatic stress. In this study we did not specifically focus on burnout. Additionally, we considered stress more generally as an element of youth development staff’s professional quality of life. Stress is made up of the internal and external challenges an individual experiences that disturb their holistic, optimal health (Bloom & Farragher, 2011). Although youth development staff stress has seen very little study, researchers have investigated teacher stress, defined as unpleasant emotions stemming from work as a teacher (Kyriacou, 2010). In addition to low quality relationships with young people, teacher stress is associated with increased burnout, absenteeism, staff turnover, emotional exhaustion, anxiety, and bias in discipline (e.g., disciplining minoritized groups more harshly than dominant groups) and reduced sense of effectiveness, job satisfaction, performance, sense of accomplishment, health, and commitment (Collie et al., 2012; Danziger et al., 2011; Herman et al., 2018; Jennings & Greenberg, 2009; Mosely, 2018; Osher et al., 2020; Sandilos et al., 2018). Traumatic stress (Bloom & Farragher, 2011) is another type of stress that may affect youth development staff in both primary and secondary ways. Primary traumatic stress occurs when an event, series of events, or set of circumstances in an individual’s life is experienced as harmful or life-threatening to them and has long-term negative effects on functioning and wellbeing (Substance Abuse and Mental Health Services Administration’s [SAMHSA] Trauma and Justice Strategic Initiative,2014 ).4 Primary trauma includes but is not limited to abuse, neglect, car accidents, natural disasters, war, life-threatening illness, assault, home invasion, incarceration, and witnessing an event first-hand. Secondary traumatic stress refers to an individual’s indirect exposure to another person’s traumatic event (e.g., learning about an event that happened to someone close to them or continued exposure to details of an event; SAMHSA, 2014).5 Those experiencing secondary trauma have similar symptoms to people who have survived primary trauma. Symptoms of secondary traumatic stress can appear almost instantly without obvious signs and may include fear, helplessness, isolation, sleep difficulties, intrusive thoughts and images, and avoidance (Figley, 1995; McCann & Pearlman, 1990). The COVID-19 pandemic is a collective trauma event (Duane et al., 2020). Collective trauma—which can occur with natural disasters (e.g., floods, earthquakes, hurricanes), mass violence (e.g., bombings, school shootings), community and health epidemics, and terrorism (e.g., domestic terrorism - mass murders of Black people and other minoritized groups; Luszczynska et al., 2009)—is described as the psychological reactions of a group of individuals after a shared experience (Ginwright, 2016; Watson et al., 2020). During collective trauma events, youth development staff may experience primary and secondary trauma at the same time, which Berger et al., (2016) called “dual trauma”. Youth development staff’s primary trauma is due to the event itself and the added stress of the profession, while their secondary trauma is from working with young people that are experiencing trauma. The symptoms related to dual trauma are the same as primary trauma, secondary trauma, and teacher stress (Berger et al., 2016). Race-based traumatic stress,6 a type of collective trauma, is specific to people of Color. Race-based trauma is caused by the stress of “individual, institutional, and cultural encounters with racism” (Carter, 2007, p. 14). In addition to overt racist acts, encounters with racism could involve microaggressions (Sue, 2010), implicit biases (Racial Equity Tools, n.d.), racist policies (Kendi, 2019), and others. Intrusion of thoughts related to the original trauma, avoidance of events associated with or similar to the traumatic experience, and hypervigilance are a few symptoms of race-based trauma (Carter, 2007). The Current Study On March 11, 2020, COVID-19 was declared a pandemic by the World Health Organization (WHO; Adhanom Ghebreyesus 2020). The COVID-19 pandemic changed everything around the world. In the United States, schools suspended in-person classes for the rest of the academic year and youth-serving organizations closed their physical doors initially. Since this was the first coronavirus pandemic (Adhanom Ghebreyesus, 2020), it is important to understand youth development staff’s experiences during this collective trauma event. Additionally, such understanding could provide insight into what to do for future collective trauma events. Through this explanatory sequential mixed methods (Creswell & Plano Clark, 2018) study, we sought to understand the experience of youth development staff in the United States during the first two months of the COVID-19 pandemic. We collected quantitative data through surveys and qualitative data through interviews to gain a holistic understanding of youth development staff’s experiences during the early months of the COVID-19 pandemic. Specifically, we asked three questions related to stress, compassion satisfaction, and race/ethnicity and gender differences, respectively: What was the stress level of youth development staff prior to and during the COVID-19 pandemic and what were they worried about? How satisfied were youth development staff with their work during the COVID-19 pandemic and what did they enjoy about their work? Are there race/ethnicity and/or gender differences in stress levels and compassion satisfaction scores? Youth development staff are vital to youth-serving organizations and during the COVID-19 pandemic they played a large role in young people’s lives as some opened their physical doors for them to be during school hours to attend online classes, complete work, and have meals and snacks. This research study has implications for how organizations can better support youth development staff during collective trauma (e.g., race-based trauma and natural disasters) events thus the development of young people. Based on the teacher stress and trauma research, we hypothesize that youth development staff will report they were more stressed during the first two months of the pandemic than they were prior to the pandemic and are generally worried about the young people they work with. Youth development staff may have experienced dual trauma due to their own personal and professional experiences with the COVID-19 pandemic and the concerns they had about the young people they work with, and their experiences related to the pandemic. In addition, youth development staff might be less satisfied with their work and feel that they need to do more to help young people. Additionally, previous research suggests that there will be race/ethnicity differences in stress levels and compassion satisfaction. Our speculation is that during the COVID-19 pandemic and specifically the spring and summer of 2020, youth development staff of Color experienced not only primary and secondary trauma related to the pandemic, but also race-based trauma due to the combination of racial disparities in health care and domestic terrorism (e.g., murders, hate crimes, and social injustices) towards them especially for Black people and Asian Americans (Darling-Hammond, 2021; Dixson et al., 2019). According to the Centers for Disease Control and Prevention (2020), “Long-standing systemic health and social inequities have put many people from racial and ethnic minority groups at increased risk of getting sick and dying from COVID-19.” Given their important role in young people’s lives, youth development staff of Color experiencing this combination of traumas likely had an impact on how they were able to support the young people they work with. Youth development staff of Color may be satisfied with their work because they could be working with young people they have similar backgrounds to (Kokka, 2016). Although previous literature in the United States has not found significant gender differences in workplace stress (Byron, 2005; White et al., 2020), we anticipate there will be differences based on the intersection of race/ethnicity and gender (Crenshaw, 1989; Hill Collins & Bilge, 2020). We hypothesize women of Color will have the highest stress level due to the intersection of racism and sexism (Essed, 1991). However, based on the teacher stress literature (Collie et al., 2012), we imagine all the race/ethnicity and gender combinations will have low compassion satisfaction scores. However, there is limited literature exploring this concept based on the intersection of race/ethnicity and gender. Through analyzing our data to address these research questions, we also uncovered basic descriptive information about how youth work was conducted during the first few months of the pandemic. Methods A PhD student led this research study and is the first author on the paper. The other co-authors are an associate professor at a Mid-Atlantic university and the director of a local intermediary. We organized and coordinated a collaborative team made up of four PhD students and a research assistant from a School of Education at a Mid-Atlantic university and three staff from a local intermediary to aid with data collection. This study was approved by our university’s Institutional Review Board on April 21, 2020. We collected data during the following few weeks—during a pandemic and a time of rapid change for youth-serving organizations. At that time, respondents were moving their programing online or cancelling programming, applying for emergency funding, and shifting the focus of their offerings. Some youth development staff were not able to be reached via their work emails because they were either laid off, fired, or no longer being paid. Sample The research team used purposive sampling by emailing, calling, and following up with members of the local afterschool intermediary. This intermediary maintained a network of youth-serving programs that had expressed a commitment to quality by participating in a quality initiative. We advertised the survey in another local intermediary’s newsletter as well. We collected data between April 21 and June 19, 2020. Respondents included 283 youth development staff (i.e., the adults working with young people) from 140 unique youth-serving organizations in a Mid-Atlantic city in the United States. Each voluntarily completed a questionnaire about their feelings, thoughts, and behaviors related to their work and the COVID-19 pandemic.7 In addition, we interviewed a subset of 25 survey respondents from 21 unique youth-serving organizations in this Mid-Atlantic city. See Table1 for descriptive statistics about the youth development staff surveyed and interviewed. Youth-serving organizations included Boys & Girls Clubs of America, Big Brothers Big Sisters, museums, school-based after school programs, community centers, libraries, faith-based programs, YMCAs, community-based programs, STEM- (science, technology, engineering, and math), environmental and arts-focused programs, and many others. Table 1 Descriptive Statistics Surveys Participants (N = 283) Interviewees (n = 25) n % n % At least 50% direct contact with young people8 132 51 11 46 People of Color9 90 34 8 32 White People 176 66 17 68 Women 214 80 17 68 Men 46 17 8 32 Nonbinary 6 2 0 0 Women of Color 66 25 410 16 Men of Color 20 7.5 411 16 Nonbinary People of Color 4 1.5 0 0 White Women 148 56 13 52 White Men 26 10 4 16 Nonbinary White People 2 0.75 0 0 Procedures Our overall design was an explanatory sequential mixed methods design (Creswell & Plano Clark, 2018), though we designed the survey and initial interview protocol at the same time. First, we collected primarily quantitative data from the survey. These data helped us determine the stress level and compassion satisfaction score of youth development staff in addition to a rudimentary awareness of what sorts of things they were worried about. After collecting these data and running descriptive analyses, we self-published a preliminary report for youth development staff in May 2020. It was distributed nationally through National Afterschool Alliance in September 2020. Additionally, we collected qualitative data from the interviews and used that information to explain the survey results more in-depth – what youth development staff were worried about and enjoyed about their work. The interviews also gave us an opportunity to better understand race/ethnicity and gender differences. All individuals that completed the survey and agreed to be interviewed were given an identification number. Then using a random number generator, interviewees were selected and emailed. In cases where individuals were no longer able to be interviewed, other individuals were randomly selected from the larger list. Members of the collaborative team conducted the interviews. We used the explanatory sequential mixed methods design for this study because we not only wanted to gather descriptive information from many youth development staff for a general understanding of stress and compassion satisfaction, but also get a better sense of what they were stressed and satisfied about. To answer our research questions, we prioritized qualitative data – the youth development staff’s stories – what Creswell & Plano Clark (2018) notates as quan QUAL. Measures Survey The introduction to the survey stated,When responding to the questions in this survey, please think about your youth work (i.e., tasks, duties, and responsibilities related to supporting young people) in relation to the present COVID-19 pandemic including the social distancing, schools closing, and stay-at-home orders. (The World Health Organization (WHO) recognized the coronavirus as a pandemic on March 11, 2020.) The research team created the survey based on our own experiences as youth development staff and what others were conveying to us at the time. We piloted the survey with a small group of youth development staff prior to sending it out more widely. It consisted of ten sets of questions; however, this study focuses on four: worries about young people, worries about themselves, stress level, and compassion satisfaction. The other questions were used in the preliminary report to assist youth development staff at the time. The Likert-type scale we created for measuring stress was simple as the survey was designed to gain a basic understanding of where youth development staff stress levels were during the first two months of the pandemic. We asked participants two questions: what was your stress level prior to the COVID-19 pandemic and what is your current stress level during the COVID-19 pandemic? Respondents selected extremely low, low, medium, high, or extremely high to report their stress level for both questions. The compassion satisfaction Likert scale was inspired by the ProQOL (Professional Quality of Life) Scale (https://proqol.org/proqol-manual), a validated measure to assess compassion satisfaction, burnout, and secondary trauma in therapists (Stamm, 2010). Given that we had a different measure for stress and were not specifically measuring burnout, we only used items related to compassion satisfaction. Four items were relevant to our study, and we adjusted the language of them to specifically apply to our sample. In addition, the research team created three additional items based on our hypotheses. Statements included those about doing more, work outside of their control, and feeling helpless – items that were reverse scored – during that time. Youth development staff responded how frequently they had specific thoughts related to their work during the COVID-19 pandemic on a scale of never, rarely, very often, and always. Out of the seven items we only used three because they had strong internal consistency and conceptually provided us a simple scale for a basic understanding of compassion satisfaction. Our final compassion satisfaction scale consisted of the following items: I am a “success” as a youth development staff during this time; I can make a difference through my work during this time; I feel satisfied with my work during this time. The Cronbach’s alpha for this new scale was 0.77 indicating acceptable internal consistency. The survey asked about stress levels and used a scale to determine compassion satisfaction scores. Additionally, respondents were able to select from a list of 10 worries. However, the survey did not allow for participants to deeply explain what they were stressed about or why they were satisfied with their work. The qualitative data from the interviews allowed for those more in-depth discussions about stressors and their satisfaction. Interviews The research team decided in the design phase which interview questions we would ask participants for the purpose of having a deeper perspective on the experience of youth development staff. The interviewers met and communicated consistently. The semi-structured interview protocol consisted of seven questions divided into three sections. See the appendix for the interview protocol. Interviewees provided verbal consent prior to the interview. Additionally, interviewers referenced participants’ survey responses to ask clarifying questions so they could explain their responses in-depth. The first section (three questions) asked participants to describe the status of youth work and young people during the COVID-19 pandemic. If it did not come up during the interview, interviewers prompted participants with questions – “do you feel as if you should be doing more – why or why not” and “do you feel depressed because of the trauma your young people are experiencing”. The next section (two questions) specifically focused on the personal wellness of the youth development staff.12 They described challenges to all aspects of their wellness and how they were staying well during the pandemic. Interviewers elicited information about anxiety, stressors about work, job security, pay, loneliness, coping skills, enjoyment in their work, and connecting to other youth development staff. The last section (two questions) focused on solutions and strategies to strengthen youth work during the pandemic. The information from this section was primarily shared with the local intermediary partner for them to better support youth-serving organizations during the early months of the COVID-19 pandemic. Analysis Plan After the initial quantitative data collection, we composed a preliminary report of basic descriptive statistics for youth development staff. While we analyzed the quantitative data and qualitative separately, we interpreted them together. We used the information from the interviews to help explain the results we found in the surveys. Quantitative Analysis To answer the first part of Research Question 1 – what was the reported stress levels prior to pandemic and during pandemic13 – we translated the Likert-type scales of extremely low, low, medium, high, or extremely high to numbers of one, two, three, four, and five respectively. Then we calculated average stress levels prior and average stress levels currently and conducted paired sample t-tests. Additionally, we computed the stress level difference (i.e., during pandemic stress level – prior to pandemic stress level) of survey participants. In the survey, respondents selected their top three concerns, worries, or preoccupations about young people or added their own. We grouped these into five categories: academic, social services, safety, health and wellness, and other. Similarly, respondents selected their top three concerns, worries, or preoccupations about themselves, and we grouped those into four categories: profession, social services, safety, health, and wellness, and other. This analysis helped us address the second part of Research Question 1 – high level groupings of what youth development staff were worried about. Similar to the stress levels scale, we converted the never, rarely, very often, and always responses for the compassion satisfaction scale to one, two, three, and four respectively to determine a score for each participant. The compassion satisfaction scale provided us with results for the first part of Research Question 2 – youth development staff’s satisfaction with their work during the COVID-19 pandemic. As identities around race/ethnicity and gender are experienced simultaneously (Carey et al., 2018; Cole 2009; Crenshaw, 1989), we took an intersectional approach to our quantitative analysis. Specifically, we examined the combination race/ethnicity and gender categories that were most prominent in our dataset: women of Color, men of Color, White women, and White men. We conducted paired sample t-tests for all survey participants and interviewees separately to compare stress level prior to pandemic vs. during pandemic for women of Color, men of Color, White women, and White men. In addition, we used ANOVA contrasts to determine significant differences among the combination race/ethnicity and gender categories (women of Color, men of Color, White women, and White men) on three outcomes: stress level during the pandemic, stress level difference, and compassion satisfaction. In the ANOVA analysis, we examined each category vs. the other three, people of Color14 vs. White people, and women vs. men. This analysis primarily addressed Research Question 3 regarding the race/ethnicity and gender differences of stress and compassion satisfaction. Qualitative Analysis We analyzed the qualitative data primarily with structural coding (Saldaña, 2016). After an initial scan of interview transcripts, several root words (stress, worry, concern, satisfy, enjoy, do more, challenge, anxiety, coping, uplift, hard, struggle, difficult, power, helpless, health, and trauma) emerged related to our research questions. We identified 446 excerpts in Dedoose from this structural coding. We coded the 446 excerpts using 4 general codes: stress, worries for young people and their families, worries for self, and compassion satisfaction. The stress and compassion satisfaction codes were used to gather narratives that supported the quantitative data. The other two codes, worries for young people and their families and worries for self, described more in-depth what youth development staff were stressed about. Results Research Question 1: What was the stress level of youth development staff prior to and during the pandemic and what were they worried about? Yeah, I mean, the biggest thing honestly for me is stress. Average stress levels reported by youth development staff during the pandemic were significantly higher than their retrospective reports of stress prior to the pandemic (3.59 during vs. 2.68 prior; t = 15.92; p < 0.001). A majority of youth development staff (73%) reported an increase in their stress level. The COVID-19 pandemic seemed to intensify the stress youth development staff were already experiencing. In terms of their worries, we divide analyses of responses into two sections: worries about young people and their families and worries about self. Worries About Young People and Their Families On the survey, youth development staff selected their top three concerns, worries, or preoccupations about the young people associated with their organization during the COVID-19 pandemic. The survey only asked about young people; however, youth development staff stated they were also concerned about the families of young people. One youth development staff member described in her interview,A lot of my anxiety is about, well, how are the kids doing, how can we help the kids, how can we get things up and running, so, we can at least help a couple of the kids in a more intensive way. Um, so, a lot of my stress is very much tied to the families. Initially, youth development staff were abruptly disconnected from young people. They were not able to immediately get a sense of how young people were doing, which caused them stress. Youth development staff worried about four themes related to young people and the families of those young people: academics, social services and resources, safety, and health and wellness. Figure1 showcases the breakdown of youth development staff’s concerns. Fig. 1 Worries, Concerns, Preoccupations for Young People; n = 282; 851 data points Academics, which included items in the context of school, was the most often selected concern in the survey, as shown in this youth development staff member’s interview quote, “I don’t want the kids that I work with to go back to school next year and basically not have advanced a grade or even fallen back.” Youth development staff were worried young people would not be prepared for the next school year. They reported being concerned young people do not have adequate resources for online learning. One youth development staff member explained in her interview, “I feel bad for the kids that don’t have the technology.” Computers and Wi-Fi were not quickly available to all students which detached them from youth development staff and virtual instruction. Academic worries also included concerns about a widening the opportunity gap, disrupted routines as one youth development staff member put it, “I think that’s my biggest thing is like they lost all that structure”, and young people’s ability to successfully learn remotely. Additionally, youth development staff mentioned the impact academics had on families. One of the interviewees noted on her survey, “I’m more worried that the educational demands thrown to parents during a stressful time has made life even more stressful for families.” This especially was a concern for students that needed a lot of assistance including those that were receiving worksheets as their instruction, younger students, and students with disabilities. Given some youth-serving organizations are considered informal learning spaces and some work closely with schools, it is reasonable that academics were a main concern of the youth development staff surveyed. The second most selected concern in the survey was lack of resources including housing, food, and therapeutic services because schools shut down. As one youth development staff member stated in her interview, “We realized that families depend on [schools] for food, for mental health services, social-emotional support, so, there are a lot of resources that families aren’t necessarily receiving during this time.” Youth-serving organizations had more flexibility than schools and transitioned into “services that maybe they weren’t providing before like specifically around being like feeding sites or dropping off different materials and things of that nature to families”. This suggests that during the early days of the pandemic, these youth development staff pivoted from providing youth development services to supporting basic life services. Even still, youth development staff worried more about the young people and families that were “resistant to outside help and resources”. Youth development staff understood there were still families they were not able to reach and were concerned about how those families were getting resources. Youth development staff reported that they were worried about the safety of young people without in-person school and youth-serving organizations. A youth development staff member in an interview tearfully stated, “School is a safe place for them. After school is a place for them and so I was like real worried about them.” For some young people, youth-serving organizations are places where they feel cared for and can express themselves in ways they cannot do so at home. Another youth development staff member, with a social work background, wondered if her academic focused organization should do more related to the unsafe home environments of some young people. Based on the interviews, the worry for many may have come from not being able to regularly check in with young people and not knowing what was going on with them. Research suggests that many parents/caregivers rely on afterschool programs (Afterschool Alliance, 2020); thus, without both in-person school and afterschool programs, particularly younger students might be left without care while parental figures are working. Additionally, youth development staff perceived parental figures to be more stressed during this time including where to find care while they work, which may lead to unsafe environments. Finally, youth development staff were concerned about the health and wellness of young people including physical health/wellness, access to health care, and trauma. A youth development staff member described her concern, “You know, beyond the academic needs that students have it’s just really like a lot for them not being able to be with friends and thinking about like mental health, thinking about, like, where they are like socially and emotionally.” A youth development staff member that works with elementary school students shared in her interview, “I think a lot of those children are really struggling with the lack of social connections they’re getting to have right now with their peers.” Young people, especially those without technology, were detached not only from youth development staff but also from their peers. Worries About Self We directly asked youth development staff about their personal wellness challenges using The Ohio State University – Student Wellness Center’s Nine Dimensions of Wellness (2020). This framework describes holistic wellness as including emotional, professional, social, spiritual, physical, financial, intellectual, creative, and environmental wellness. Professional and personal (i.e., emotional, physical, and social) challenges were the most talked about topics. Professionally, youth development staff were concerned about using online tools needed as they transitioned to the virtual environment. Some of the self-worries were related to the young people the youth development staff worked with. This mimics the dual trauma literature. In her interview, one youth development staff member said, “That was the hardest transition for me just not getting to see them and not getting to hear from them consistently.” The worry youth development staff had about young people impacted their own health as well. One of the main themes for youth development staff that showed up in both the surveys and interviews is they thought they should be doing more and wanted to do more. In those responses were a sense of helplessness, they wanted to do more but did not know what to do especially at first. This can be seen in this response,There’s like a little bit of like helplessness to it being like, okay, I can do some things but like really there’s like only so much in that space…. So it’s a little bit yeah I guess just floating in kind of that uncertainty of like what could I be doing that is helping with this period. Initially, many youth development staff were unsure of what to do and how to do it. They did not know exactly what families needed because they were not able to get in contact with all of them to ask. Additionally, in those responses of wanting to do more, youth development staff felt ineffective. In her interview a youth development staff member shared,I feel like I don’t know that I’m being as effective as I could be…I think part of my effectiveness comes from…my ability to move my vision forward and move the work forward and so I feel like because we sat in the space of an unknown for a long time...So I just felt like kind of really stag[nant] like in this place of, like, I know things have to be done and we’re not moving. The social aspect of wellness was a challenge for youth development staff even for those that shared they were an introvert. The following quote from an interview describes the impact the lack of social connections had on one youth development staff member’s emotional health,I think that social and emotional are pretty, pretty connected. I mean, for me at least, like I like being around people. I like being around the people that like are my friends and family like So when I can’t do that. Like, it can take a toll on emotional wellness. Regarding emotional aspect of wellness, in an interview one youth development staff stated, “I was challenged emotionally because I was experiencing a lot of different emotions from like fear to sadness to being hopeful and then going back to, you know, being a being anxious.” Youth development staff experienced a wide range of emotions due to the uncertainty of the pandemic. There were unknowns in their professional life but also in their personal lives. Youth development staff weren’t sure if they were going to continue to be employed or if they would have to take a pay cut and they were anxious about contracting COVID-19. Lastly, the physical aspect of wellness was something youth development staff were concerned about. They mentioned not getting enough exercise and their more sedentary lifestyles. Research Question 2: How satisfied were youth development staff with their work during the pandemic and what did they enjoy about their work? The average compassion satisfaction score for all survey respondents was 7.35 (min. 3 and max. 12). Although youth development staff reported experiencing stress, they were also satisfied with aspects of their work. They concentrated on doing work that was within their control and tried to look at what they could do to cope with the monstrosity of the pandemic. One man explained he focused on what he can do to help even just a few young people through his work. He described in his interview, “Yes, we’re not teaching every single kid in [city], at the moment, but we’re teaching some and that’s like trying trying and it’s making impact for their lives. And so, little by little, trying to expand that.” In an interview another youth development staff member described the same sentiment,I have like from the beginning to even now, I’m just like, putting energy into doing as much as I can, you know what I mean. And just even if I’ve don’t actually like talk to them on the phone, I know that like leaving them a message that I was calling to check in on them and see how they’re doing. I feel like I have control over that. For some youth development staff, they begin either volunteering outside of their organization or doing different work in their organization. In the interviews, youth development staff detailed a contrast of feeling helpless especially at first, yet also striving to do something to support the young people they work with and their families. Youth development staff described perspective shifting as helping them with alleviating some of the stress and ineffectiveness they were feeling, as seen in the above quotes. In addition, they described focusing intensely on what they had control over. For instance, they didn’t have control over who responds to their outreaches, but they continued to outreach. For those they could reach, they provided the best services they could. One youth development staff described the pandemic as an opportunity “to do something a little radical” with how they serve young people. Research Question 3: Are there race/ethnicity and/or gender differences in stress levels and compassion satisfaction scores? Generally, youth development staff reported being more stressed during the first two months of the pandemic than prior to the pandemic; however, they also reported satisfaction doing work that was in their control. This pattern largely was consistent across the most prominent race/ethnicity and gender combinations in our dataset: women of Color, men of Color, White women, and White men. Fig. 2 Average Reported Stress Levels Prior to and During the First Two Months of the COVID-19 Pandemic by Race/Ethnicity and Gender on a Scale 1–5; n = 25915. *All prior-during differences are statistically significant (p < 0.001) As shown in Fig.2, White women had the highest reported stress level during the pandemic compared to women of Color, White men, and men of Color respectively (F1,255=6.24, p < 0.05). Men of Color had the largest average increase (1.3) in stress level from prior to during the pandemic (F1,255=4.17, p < 0.05), as well as the lowest reported average stress level for both prior to pandemic and during pandemic. On average, men of Color increased their stress level by 1 category (i.e., medium to high). One Black man reported an increase of his stress level by 4 (i.e., he reported a stress level extremely low prior to the pandemic and extremely high during the pandemic). While none of the other groups averaged an increase of more than 1, on average all groups reported they were more stressed during the first two months of the pandemic than prior to the pandemic. Some people of Color identified race/ethnicity as a factor in their increased stress level. An Asian American woman detailed her experiences in an interview,I would notice some side eyes when we’re [she and her husband] at the store like oh, she’s Asian. That’s going to happen naturally because where we are it’s not, there’s not a lot of me. But we noticed, I noticed it more especially, the first couple weeks just kind of those side eyes never anything said to me or anything like that. So that was that’s probably another you know stressor for me that I would have a harder time admitting. Fig. 3 Average Compassion Satisfaction Score by Race/Ethnicity and Gender; n = 25516 As shown in Fig.3, men of Color had the highest average compassion satisfaction score (8.75) compared to women of Color, White men, and White women (7.45, 7.38, and 7.04 respectively) (F1,254=11.96, p < 0.001). White women’s average score was significantly lower than the other groups (F1,254=12.53, p < 0.001). There was a statistically significant difference in average compassion satisfaction scores between women and men of Color vs. White women and men (F1,254=9.75, p < 0.01). Women and men of Color in this sample, on average, have higher compassion satisfaction scores. Additionally, the average compassion satisfaction scores of women of Color and White women were statistically different than men of Color and White men (F1,254=7.58, p < 0.01). The data from the survey participants display racial/ethnic and gender differences in reported stress levels and compassion satisfaction scores during the first two months of the COVID-19 pandemic. Discussion Interpretation of Results The results show that the professional quality of life of youth development staff in this study changed during the early months of the COVID-19 pandemic. Stress Our hypothesis about stress was confirmed – youth development staff reported higher stress levels during the pandemic than prior to the pandemic. Though many youth development staff in the study stated they were not experiencing the trauma of young people, their experiences mimicked the secondary trauma described in teacher stress literature (SAMHSA, 2014). Youth development staff said they experienced challenges related to their personal wellness (emotional, physical, and social) and they described being stressed about the young people they work with and their families. These results demonstrated how a collective trauma event can impact youth development staff – they did not just think of themselves and how the pandemic affected them but also how it impacted the young people and families. Many reported feeling ineffective and helpless in their jobs in particular, which also may have led to their higher stress levels (Herman et al., 2018; McCann & Pearlman, 1990). Youth development staff believed a lot of what was going on with young people and families during the pandemic was beyond the scope of what they could help with. Yet, some youth-serving organizations expanded their offerings so youth development staff could address the perceived needs of young people and their families (e.g., tutoring, serving meals, and wellness calls). Some also opened their physical doors to provide spaces for young people to participate in virtual schooling. Additionally, youth development staff were worried about the trauma young people might experience as a result of not having a safe place to be after school – a role they believed their youth-serving organizations fulfilled (Afterschool Alliance, 2020). Related to themselves, youth development staff worried about switching to a virtual environment and being cut off not just from young people but also from other staff, family, and friends. This isolation impacted their emotional health. Their emotional health was also impacted by uncertainties both in their professional and personal lives (e.g., staying employed, being paid, and having COVID-19). Satisfaction Given we believed youth development staff would have increased stress levels, we also anticipated they might be less satisfied with their work and feel they needed to do more to help because the early months of the COVID-19 pandemic halted much of their work (Stamm, 2010). However, we found that they dedicated their time and energy to what they could do. Many were pleased with conducting what they deemed meaningful work and focused on the impact of the work they conducted for young people and families. Even with a less than ideal work environment (e.g., not being in contact with young people), youth development staff were determined to figure out ways to still support young people and families through meal deliveries and continued wellness calls, texts, and voicemails. Race/Ethnicity and Gender Differences Even though the average reported stress levels prior to and during the first two months of the COVID-19 pandemic for each race/ethnicity and gender pairing (i.e., women of Color, men of Color, White women, and White men) were statistically different, only the average stress level during the pandemic for White women was statistically different than the other three groups. Additionally, White women had the lowest average compassion satisfaction score. Thus, White women in our study followed the expected pattern in the teacher stress literature (i.e., high stress levels and low compassion satisfaction; Collie et al., 2012). Men of Color, however, did not follow the identified pattern in the teacher stress literature. Although men of Color had the highest compassion satisfaction score and the lowest self-reported stress level, they had the largest reported increase in their average stress level from prior to the pandemic to during the pandemic. Racism (e.g., hate crimes, social injustices, and racial disparities in health care) might explain this phenomenon with both men of Color and women of Color (Dixson et al., 2019). When a hate crime happens, even if it is not happening to someone they know personally, individuals that identify as being in the same group may react in the same way as if it was happening to them or someone close to them. This is the idea of collective trauma (Luszczynska, 2009; Watson et al., 2020). Moreover, according to the race-based trauma literature, racism negatively impacts the stress level of people of Color (Carter, 2007). During the first few months of the pandemic in the United States, there were also many nationally publicized acts of violence perpetuated on Black individuals, that may have increased the stress level of Black youth development staff in addition to the COVID-19 pandemic (Alter, 2020). Similarly, Asian Americans faced increased xenophobia and discrimination during this time in part due to scapegoating of COVID-19 (Wang et al., 2020). There were more statistically significant differences in compassion satisfaction scores by race/ethnicity and gender groups than differences in stress levels. The higher compassion satisfaction scores of youth development staff of Color may reflect the sense of fulfillment they received from working with young people of similar backgrounds and experiences as themselves. Youth development staff of Color might also gain satisfaction from their work because they are striving towards a more just and equitable society for people of Color (Kokka, 2016). Our study supports this as women and men of Color in this sample, on average, have higher compassion satisfaction scores than White women and men. We did find the average compassion satisfaction scores of women of Color and White women were statistically different than men of Color and White men. Given these findings are inconsistent with other research, we believe deeper research is needed. Parameters This study was bounded by its one-moment-in-time nature, and the boundaries of the data collection methods. Participants responded to the stress measure based on their own interpretation of stress. It might have been advantageous to provide definitions of the different types of stress including specifically asking about other collective trauma events (e.g., race-related or gender-related stress) in both the survey and interview. The compassion satisfaction score did not have a before score to compare and observe if there were changes during the first months of the pandemic. Additionally, the scale focused specifically on the helping aspects of the job related to the COVID-19 pandemic and not general aspects of their job that could also cause them stress such as high workload and responsibilities (Collie et al., 2012; Sandilos, 2018). Implications for Future Practice and Research Our findings have implications for future practice and research specifically related to collective trauma (e.g., natural disasters, mass violence, community and health epidemics, terrorism, and race-based trauma). We recommend organizational leaders provide youth development staff with support before a collective trauma event occurs. They can work to change, add, or remove policies, practices, and routines to help decrease stress and increase compassion satisfaction. While these results provided a glimpse into how youth development staff respond when a collective trauma event, in this case a health pandemic, occurs, several questions remain about youth development staff stress and compassion satisfaction. What are youth development staff stressed about beyond COVID-19? Similarly, what contributes to youth development staff’ compassion satisfaction? We saw some race/ethnicity and gender differences in stress and compassion satisfaction; are these differences consistent for other collective stressors and traumas (e.g., incidents happening in communities, events affecting specific populations, or the loss of a young person)? Youth development staff’s stress and compassion satisfaction are in part a result of their work environment (Stamm, 2010); thus, we need to explore youth-serving organizations more as well. Youth-serving organizations are critical parts of learning ecosystems (Akiva et al., 2020) and we need to know about them for the benefit of their youth development staff’s wellbeing and ultimately the development of young people (National Scientific Council on the Developing Child, 2009). In the sample in this study, there was an imbalance in race/ethnicity and gender. However, lack of research makes it difficult to tell if it is representative of the youth-serving field. Future research could explore the characteristics of who is in the youth-serving field. Although some may see youth development staff in youth-serving organizations as just babysitters and not value their role in the learning ecosystem for young people, during the COVID-19 pandemic they proved to be critical and valuable members of the learning ecosystem through serving young people during the school day (e.g., academic support, meals, and check-in calls). Related to practice, now that schools are mostly reopened and in-person, teachers and administrative staff can continue to work with youth development staff to ultimately support young people holistically. During other collective trauma events, youth-serving organizations might be able to provide support to young people and families in ways schools do not have the capacity to do, such as delivering resources to young people and families. However, further research could investigate this more. How do youth-serving organizations respond to their youth development staff, young people, and families during collective trauma events? What strategies do they use to support youth development staff as they work to decrease their stress and increase their compassion satisfaction during collective trauma events? Even though this study focuses on collective trauma events, youth development staff conduct critical work, but generally they may not be supported by their organization or their supervisors (Ewing, 2021). Supporting youth development staff before there is an incident might better prepare organizational leaders to support them during the initial months of other collective trauma events. Organizational leaders can work to change the staffing climate (e.g., policies, practices, and routines) to better assist youth development staff such as eliminating high stakes work performance measures and promoting work-life balance. One way supervisors can show care for youth development staff’s wellbeing is by providing spaces and times during the workday to allow youth development staff to discuss their stressors and work collectively on their healing (Ewing, 2021; White et al., 2020). Specifically, organizational leaders can work to decrease the stress of women and youth development staff of Color by creating structures that benefit them (e.g., flexible work from home policies, affinity groups for youth development staff of Color, and antiracist policies; Dixson et al., 2019; Mosely, 2018 ; White et al., 2020). Presenting youth development staff with resources needed to adequately support young people and comprehensive professional development opportunities are potential ways to buffer against the effects of job stress (Jennings & Greenberg, 2009; White et al., 2020). Professional development opportunities could also include suggesting strategies to aid youth development staff with decreasing their feelings of helplessness and facilitating self-efficacy related to their job (Collie et al., 2012). Although we recommend implementing these suggestions before an incident occurs, we also believe they could be used during the initial months of other collective trauma events. In addition, based on our results from this study our primary recommendation specific to collective trauma events, after taking care of their own personal wellness, is for youth development staff to focus on what is in their control and work to do those things for as many people as they can (e.g., making wellness calls to understand the needs of young people and families and connect them to services/resources). In this study we did not deeply explore differences between youth development staff that spend more time directly with young people and those that mostly work indirectly with young people. This difference could be interesting to investigate because both groups may be stressed but there may be differences in their stressors. For instance, those with higher levels of direct contact, might be more concerned about the young people themselves and those with less direct contact may be worried about grants and keeping direct service staff employed. The COVID-19 pandemic impacted youth development staff’s professional quality of life – their stress levels increased, yet they still found satisfaction through the work they were able to do during that time. However, stress is not confined to just the COVID-19 pandemic. We can apply the findings from this study to everyday stressors and other collective traumatic events such as race-based trauma and domestic terrorism. It’s critical for organizational leaders in youth-serving organizations to support youth development staff – helping to decrease their stress and increase their compassion satisfaction. Appendix [This section is estimated to take about 15min.] How do you think our local community is doing in terms of supporting youth during the COVID-19 pandemic? We’re really interested in how youth work is being conducted during the COVID-19 pandemic. In the Google document you read youth work as engagement with young people to support their development. How are you personally conducting youth work during the pandemic? [Reference their survey results if necessary.] [If it does not come up, specifically ask ‘do you feel as if you should be doing more – why or why not?’] 3. How do you think the young people associated with your organization are doing during the COVID-19 pandemic? [Reference their survey results if necessary, in particular their top 3 concerns, worries, or preoccupations.] [If it does not come up, specifically ask about how this is impacting them – ‘do you feel you are experiencing the trauma of your young people or do you feel depressed because of the trauma your young people are experiencing?’] We are also interested in your personal wellness during this time. To help guide our conversation, I am going to put 9 dimensions of wellness on the screen. [Pull up the 9 Dimensions of Wellness picture on your screen and share it.] [This section is estimated to take about 20min.] What challenges are you facing with your wellness during the COVID-19 pandemic? [If it does not come up, specifically ask about: anxiety, stressors about work, being fired/let go/furloughed/job security, not being paid or being paid less/benefits, loneliness, nothing has changed since before the pandemic.] How are you staying well during the COVID-19 pandemic? [If it does not come up, specifically ask about coping skills, what they are enjoying about youth work, what other youth development staff are they connecting to and how.] [This section is estimated to take 15min.] 3. As you think about solutions and strategies for youth development staff during the COVID-19. 4. As mentioned in the survey, the [university] is doing this study in partnership with [intermediary] and we’d like to explicitly share with them ways they can support youth development staff during the COVID-19 pandemic. What do you imagine an intermediary could do to support you and your organization? [If it does not come up, specifically ask about advocacy to decision makers, online educational resources to share with families, financial/emotional/medical resources for them, updates on COVID-19 relevant to youth work, professional development experiences – training sessions, professional learning communities, toolkits] 5. Is there anything else you want to add before we end? Acknowledgements We thank Tanya Baronti, Damon Bethea, Dr. Sharon Colvin, Erin Gatz, Dr. Marijke Hecht, Tracy Medrano, Jaron Paul, and Mario Quinn Lyles for assistance in collecting data. We also thank Dr. Lori Delale-O’Connor and Dr. Kari Kokka for providing feedback on the initial draft of the manuscript. Funding This study was funded in part by Heinz Endowments. Data Availability The data that support the findings of this study are available from the corresponding author, DWS, upon reasonable request. Declarations Declarations No potential competing interest was reported by the authors. Ethics Approval This study was approved by University of Pittsburgh’s Institutional Review Board on April 21, 2020. 1 We use the broad term of youth-serving organizations; however, the following terms are synonyms or closely related: out-of-school time programs, out-of-school learning environments, afterschool programs, informal education programs, and extended learning opportunities. 2 Informal educator, youth worker, youth care worker, and afterschool worker are other terms to describe adults in youth-serving organizations (Akiva et al., 2020). 3 Race and ethnicity are not the same; however, we use the terms together because this is how we referenced them in our survey to be inclusive of individual preferences. Our prompt stated: “Race/Ethnicity: Please select all that apply and write in how you identify if it is not represented”. Participants were given the following options: Black, Latinx, Native American, White, East Asian, Indian, Pacific Islander, and Middle Eastern. According to the Publication Manual of the American Psychological Association (2020), “race refers to physical differences that groups and cultures consider socially significant [and] ethnicity refers to shared cultural characteristics such as language, ancestry, practices, and beliefs” (p. 142). 4 In addition to primary traumatic stress, we will use the terms first-hand and primary trauma. 5 We will use second-hand, secondary trauma, and secondary traumatic stress interchangeably. 6 We will use race-based traumatic stress and race-based trauma interchangeably. 7 For the purposes of this report, the data from school professionals who were not associated with out-of-school time (OST) programming were not used (n = 22). The data for youth development staff not in the specific Mid-Atlantic city were not used (n = 2). Furthermore, there were 16 surveys that were missing demographic information: the other information from these surveys was still used. 8 Twenty-four survey respondents (8% of the sample) and 1 interviewee (4% of interviewees) did not answer this question. 9 Seventeen youth development staff (6% of the sample) did not respond to the race/ethnicity and gender questions. People of Color includes those that identified as Black (n = 64), Latinx (n = 8), Native American (n = 0), East Asian (n = 0), Indian (n = 2), Pacific Islander (n = 1), Middle Eastern (n = 0), self-identified (Haitian American and Hebrew Israelite), and multi-racial (n = 13) on the survey. 10 Three women of Color interviewees identified as Black and one identified as Asian American/Pacific Islander. 11 All the men of Color interviewees identified as Black. 12 The Nine Dimensions of Wellness from the Ohio State University (https://swc.osu.edu/nine-dimensions-of-wellness) – Student Wellness Center (2020) provided a framework for a portion of the conversation. 13 Youth development staff were asked both these questions (what was your stress level prior and what is your current stress level) at the time of the survey. 14 We combined those that identified as Black, Latinx, Native American, East Asian, Indian, Pacific Islander, Middle Eastern, and multi-racial into youth development staff of Color due to low individual group numbers. 15 Missing nonbinary, no combination race/ethnicity and gender response, and no stress response. 16 Missing nonbinary, no combination race/ethnicity and gender response, and no compassion satisfaction score Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Adhanom Ghebreyesus, T. (2020). WHO director-general’s opening remarks at the media briefing on COVID-19–11 March 2020. World Health Organization. https://www.who.int/dg/speeches/detail/who-director-general-s-opening-remarks-at-the-media-briefing-on-covid-19---11-march-2020 Afterschool Alliance (2020). America after 3pm:Demand grows, opportunity shrinks. http://afterschoolalliance.org/documents/AA3PM-2020/AA3PM-National-Report.pdf Akiva T Delale-O’Connor L Pittman KJ The promise of building equitable ecosystems for learning Urban Education 2020 00 0 1 27 10.1177/0042085920926230 Akiva, T., Hecht, M., & Blyth, D. A. (2021). Using a learning and development ecosystem framework to advance the youth fields. In T. Akiva, & K. Robinson (Eds.), It takes an ecosystem: Understanding the people, places, and possibilities of learning and development across settings. Information Age Publishing, Inc Alter, C. (2020). ‘America Has Its Knee on People of Color.‘ Why George Floyd’s Death Was a Breaking Point. TIME. https://time.com/5845752/america-has-its-knee-on-us-george-floyds-death-was-a-breaking-point-protests/ American Psychological Association. (2020). Publication manual of the American Psychological Association. American Psychological Association Berger R Abu-Ralya H Benatov J Reducing primary and secondary traumatic stress symptoms among educators by training them to deliver a resiliency program (ERASE-Stress) following the Christchurch earthquake in New Zealand American Journal of Orthopsychiatry 2016 86 2 236 251 10.1037/ort0000153 26963188 Bloom, S. L., & Farragher, B. (2011). Destroying sanctuary: The crisis in human service delivery systems. Oxford University Press Byron, K. (2005). A meta-analytic review of work–family conflict and its antecedents. Journal of Vocational Behavior, 67(2), 169–198. 10.1016/j.jvb.2004.08.009 Carey RL Akiva T Abdellatif H Daughtry KA ‘And school won’t teach me that!’ Urban youth activism programs as transformative sites for critical adolescent learning Journal of Youth Studies 2020 10.1080/13676261.2020.1784400 Carey RL Yee LS DeMatthews D Power, penalty, and critical praxis: Employing intersectionality in educator practices to achieve school equity The Educational Forum 2018 82 1 111 130 10.1080/00131725.2018.1381793 Carter RT Racism and psychological and emotional injury: Recognizing and assessing race-based traumatic stress The Counseling Psychologist 2007 35 1 13 105 10.1177/0011000006292033 Centers for Disease Control and Prevention (2020). Health equity considerations & racial & ethnic minority groups. https://www.cdc.gov/coronavirus/2019-ncov/community/health-equity/race-ethnicity.html Cole ER Intersectionality and research in psychology American Psychologist 2009 64 3 170 180 10.1037/a0014564 19348518 Collie RJ Shapka JD Perry NE School climate and social-emotional learning: Predicting teacher stress, job satisfaction, and teaching efficacy Journal of Educational Psychology 2012 104 4 1189 1204 10.1037/a0029356 Crenshaw K Demarginalizing the intersection of race and sex: A black feminist critique of antidiscrimination doctrine, feminist theory and antiracist politics University of Chicago Legal Forum 1989 1989 1 139 167 Creswell, J. W., & Plano Clark, V. L. (2018). Designing and conducting mixed methods research (3rd ed.). Sage Danziger, S., Levav, J., & Avnaim-Pesso, L. (2011). Extraneous factors in judicial decisions. Proceedings of the Nation Academy of Sciences of the United States of America, 108(17), 6889–6892. 10.1073/pnas.1018033108 Darling-Hammond, L. (2021). Accelerating learning as we build back better. Forbes. https://www.forbes.com/sites/amazonwebservices/2021/06/28/show-your-customer-obsession-with-these-4-rules-of-personalization/?sh=2cd5b924240d Dixson, A. D., James, A., & Frieson, B. L. (2019). Taking it to the streets: Critical race theory, participatory, research, and social justice. In J. T. DeCuir-Gunby, T. K. Chapman, & P. A. Schultz (Eds.), Understanding critical race research methods and methodologies (pp. 64–75). Taylor & Francis Duane AM Stokes KL DeAngelis CL Bocknek EL Collective trauma and community support: Lessons from Detroit Psychological Trauma: Theory Research Practice and Policy 2020 12 5 452 10.1037/tra0000791 32525364 Essed, P. (1991). Understanding everyday racism: An interdisciplinary theory. SAGE Publications, Inc Ewing, S. (2021). Compassion fatigue is overwhelming educators during the pandemic. EducationWeek. https://www.edweek.org/teaching-learning/opinion-compassion-fatigue-is-overwhelming-educators-during-the-pandemic/2021/06?utm_source=fb&utm_medium=soc&utm_campaign=edit&fbclid=IwAR0meMsxg7sDaLetYl3wo-BAqr4czIJJZl9ZkF_hcEQn21ci7ZWQZt2_x0Y Figley, C. R. (1995). Compassion fatigue as secondary traumatic stress disorder: An overview. In C. R. Figley (Ed.), Compassion fatigue: Coping with secondary traumatic stress disorder in those who treat the traumatized (pp. 1–20). Taylor & Francis Group, LLC Ginwright, S. (2016). Hope and healing in urban education: How urban activists and teachers are reclaiming matters of the heart. Routledge Halpern, R. (2003). Making play work: The promise of after-school programs for low-income children. Teachers College Press Herman KC Hickmon-Rosa J Reinke WM Empirically derived profiles of teacher stress, burnout, self-efficacy, and coping and associated student outcomes Journal of Positive Behavior Interventions 2018 20 2 90 100 10.1177/1098300717732066 Hecht M Crowley K Unpacking the learning ecosystems framework: Lessons from the adaptive management of biological ecosystems Journal of The Learning Sciences 2020 29 2 264 284 10.1080/10508406.2019.1693381 Hill Collins, P., & Bilge, S. (2020). Intersectionality (2nd ed.). Polity Press Jaracz M Rosiak I Bertrand-Bucińska A Jaskulski M Nieżurawska J Borkowska A PLoS ONE 2017 12 6 1 11 10.1371/journal.pone.0176698 Jennings PA Greenberg MT The prosocial classroom: Teacher social and emotional competence in relation to student and classroom outcomes Review of Educational Research 2009 79 1 491 525 10.3102/0034654308325693 Kendi, I. X. (2019). How to be an antiracist. One World Kokka, K. (2016). Urban teacher longevity: What keeps teachers of color in one under-resourced urban school? Teaching and Teacher Education, 59(2016), 169–179. 10.1016/j.tate.2016.05.014 Kyriacou C Teacher stress: Directions for future research Educational Review 2010 53 1 27 35 10.1080/00131910120033628 Ladson-Billings G Culturally relevant pedagogy 2.0: a.k.a. the remix Harvard Educational Review 2014 84 1 74 135 10.17763/haer.84.1.p2rj131485484751 LeMenestrel, S. M., & Lauxman, L. A. (2011). Voluntary youth-serving organizations: Responding to the needs of young people and society in the last century.Journal of Youth Development, 6(3). https://jyd.pitt.edu/ojs/jyd/article/view/171/157 Li J Julian M Developmental relationships as the active ingredient: A unifying working hypothesis of “what works” across intervention settings American Journal of Orthopsychiatry 2012 82 2 157 166 10.1111/j.1939-0025.2012.01151.x 22506517 Locke EA What is job satisfaction? Organizational Behavior and Human Performance 1969 4 309 336 10.1016/0030-5073(69)90013-0 Luszczynska A Benight CC Cieslak R Self-efficacy and health-related outcomes of collective trauma: A systematic review European Psychologist 2009 14 1 51 62 10.1027/1016-9040.14.1.51 McCann IL Pearlman LA Vicarious traumatization: A framework for understanding the psychological effects of working with victims Journal of Traumatic Stress 1990 3 1 131 149 10.1007/BF00975140 McLaughlin MW Irby MA Urban sanctuaries: Neighborhood organizations that keep hope alive The Phi Delta Kappan 1994 76 4 300 306 McLaughlin, M. W., Irby, M. A., & Langman, J. (1994). Urban sanctuaries: Neighborhood organizations in the lives and futures of inner-city youth. Jossey-Bass Morrison, J. K. (2014). Employer strategies for supporting out of school time programming in Texas: Incentives for action, opportunities for collaboration. The Bush School of Government & Public Service Texas A&M University. https://www.edtx.org/getattachment/49e4dc31-497c-40c4-8096-12d88897b08a/GetFile.aspx Mosely M The black teacher project: How racial affinity professional development sustains black teachers The Urban Review 2018 50 2 267 283 10.1007/s11256-018-0450-4 National Scientific Council on the Developing Child (2009). Young children develop in an environment of relationships. Working paper 1. https://46y5eh11fhgw3ve3ytpwxt9r-wpengine.netdna-ssl.com/wp-content/uploads/2004/04/Young-Children-Develop-in-an-Environment-of-Relationships.pdf Osher D Cantor P Berg J Steyer L Rose T Drivers of human development: How relationships and context shape learning and development Applied Developmental Science 2020 24 1 6 36 10.1080/10888691.2017.1398650 Racial Equity Tools (n.d.). Implicit Bias. Racial Equity Tools. https://www.racialequitytools.org/act/communicating/implicit-bias Saldaña, J. (2016). The coding manual for qualitative researchers (3rd ed.). Sage Sandilos LE Goble P Rimm-Kaufman SE Pianta RC Does professional development reduce the influence of teacher stress on teacher–child interactions in pre-kindergarten classrooms? Early Childhood Research Quarterly 2018 42 280 290 10.1016/j.ecresq.2017.10.009 Stamm, B. H. (2010). The concise ProQOL manual. https://proqol.org/proqol-manual Substance Abuse and Mental Health Services Administration’s Trauma and Justice Strategic Initiative (2014). SAMHSA’s concept of trauma and guidance for a trauma-informed approach. HHS Publication No. (SMA) 14-4884. Substance Abuse and Mental Health Services Substance Abuse and Mental Health Services Administration. (2014). Trauma-informed care in behavioral health services (pp. 14–4816). HHS Publication No. (SMA Sue, D. W. (2010). Microaggressions: More than just race.Psychology Today. https://www.psychologytoday.com/us/blog/microaggressionsineveryday-life/201011/microaggressions-more-just-race The National Child Traumatic Stress Network (2017). Addressing race and trauma in the classroom: A resource for educators. https://www.nctsn.org/sites/default/files/resources//addressing_race_and_trauma_in_the_classroom_educators.pdf The Ohio State University – Student Wellness Center (2020). Nine dimensions of wellness. Office of Student Life Student Wellness Center. https://swc.osu.edu/about-us/nine-dimensions-of-wellness/ Vance F A comparative analysis of competency frameworks for youth development staff in the out-of-school time field Child & Youth Care Forum 2010 39 421 441 10.1007/s10566-010-9116-4 21170418 Wang D Gilbert CG Bahiru E Yang EH Hsu JJ Asian-Americans and Pacific Islanders in COVID-19: Emerging Disparities Amid Discrimination Journal of General Internal Medicine 2020 35 3685 3688 10.1007/s11606-020-06264-5 33009656 Watson MF Bacigalupe G Daneshpour M Han W Parra-Cardona R COVID-19 interconnectedness: Health inequity, the climate crisis, and collective trauma Family Process 2020 59 3 832 846 10.1111/famp.12572 32589267 White AM DeMand A McGovern G Akiva T Understanding youth development staff job stress Journal of Youth Development 2020 15 1 47 69 10.5195/jyd.2020.817 Yohalem, N., Pittman, K., & Moore, D. (2006). Growing the next generation of youth professionals: Workforce opportunities and challenges. Cornerstones for Kids
PMC009xxxxxx/PMC9465055.txt	==== Front Fam J Alex Va Fam J Alex Va TFJ sptfj Family Journal (Alexandria, Va.) 1066-4807 1552-3950 SAGE Publications Sage CA: Los Angeles, CA 10.1177/10664807221123556 10.1177_10664807221123556 COVID-19 Pandemic Parental Burnout During the Second Year of the COVID-19 Pandemic: Exploring the Role of Parenting Stressors and Coparenting Support https://orcid.org/0000-0003-2278-9308 Vaydich Jenny Lee 1 Cheung Rebecca Y. M. 2 1 Department of Psychology, 7282 Seattle Pacific University , Seattle, WA, USA 2 Department of Early Childhood Education, The Education University of Hong Kong, Hong Kong, Hong Kong Special Administrative Region of China Jenny Lee Vaydich, PhD, Department of Psychology, Seattle Pacific University, 3307 3rd Ave West, Seattle WA 98119 USA. Email: [email protected] 7 9 2022 7 2023 7 9 2022 31 3 432442 © The Author(s) 2022 2022 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. The COVID-19 pandemic brought about many changes in family routines and introduced new stressors for parents. While stressors can lead to parental burnout, coparenting support may mitigate the effects of parental stress on parental burnout. The current study explored the effects of parental stress, COVID-19 stress, and coparenting support on parental burnout during the second year of the pandemic. Participants consisted of one hundred fifty-five parents in the USA (M = 39.6, SD = 7.38; female = 94.8%). Results suggested parental stress was positively associated with parental burnout while coparenting support was negatively associated with parental burnout. These findings highlight the importance of addressing parental stress and support to minimize the risk of parental burnout. parental stress coparenting support parental burnout COVID-19 typesetterts19 ==== Body pmcThe outbreak of coronavirus disease 2019 (COVID-19) was not only a threat to public health (Palacios Cruz et al., 2021), but the pandemic also posed risks for families due to its financial and social implications (e.g., Dawes et al., 2021; Prime et al., 2020). Lockdowns and social restrictions presented challenges for parents and families, including school closures, reduced interactions with children's peers, disrupted child and family routines, job loss, changes in support networks, and COVID-19-related stress (Adams et al., 2021; Dawes et al., 2021; Posel et al., 2021; Rao & Fisher, 2021). Thus, the COVID-19 pandemic has introduced a number of new stressors for many parents. Parenting is complex and demanding, bringing periods of stress and even feelings of burnout for some parents (Abidin, 1990; Roskam et al., 2018). Parental burnout is defined by intense exhaustion due to parenting, loss of fulfillment as a parent, emotional distancing from one's child, and a perceived contrast between one's previous and current parental self (Mikolajczak et al., 2019). These feelings may be a natural reaction to the stress and demands of childrearing. For 5–20% of parents, chronic or intense stress may lead to parental burnout (Roskam et al., 2018; Séjourné et al., 2018), which can have wide-ranging consequences for parents, including substance use, somatic symptoms, hypothalamic–pituitary–adrenal axis dysregulation as well as suicidal and escape ideations (Brianda et al., 2020a, 2020b; Mikolajczak et al., 2018a, 2019). Research on parental burnout is rapidly growing (Mikolajczak et al., 2019), and studies suggest parents experienced an increased risk for burnout during the pandemic (Bastiaansen et al., 2021; Griffith, 2020; van Bakel et al., in press), as well as the negative outcomes associated with parental burnout. Due to the impact parental burnout can have on parental mental and physical health (Brianda et al., 2020b; Mikolajczak et al., 2019), parenting behaviors (Mikolajczak et al., 2019), and child well-being (Brianda et al., 2020a; Mikolajczak et al., 2018a, 2019), it is important to examine the risk and protective factors associated with parental burnout during the COVID-19 pandemic. A major risk factor for parental burnout is parental stress, particularly if stressors are experienced as overwhelming. Natural disasters and pandemics are events that can bring about significant stressors for parents that are abrupt and intense (Frankel et al., 2021; Hausman et al., 2020). Furthermore, the COVID-19 pandemic introduced stressors that were both unpredictable and long-lasting for many parents as the pandemic continued for multiple years. Thus, the nature of these stressors may have placed parents at risk for parental burnout, especially as the pandemic continued into the second year. Theoretical Framework The COVID-19 pandemic brought about new challenges and demands for many parents and their families, increasing the risk for parental burnout. Many parents navigated working and schooling their children from home in the absence of previous resources such as daycare or after-school programs for children. The Balance Between Risks and Resources (BR2) theory suggests parental burnout is due to a chronic imbalance between perceived parenting demands and resources (Mikolajczak & Roskam, 2018). Parenting demands include risk factors that increase parenting stress while resources refer to protective factors that minimize parental stress. Caring for children during the pandemic introduced new parenting demands; however, coparenting support may have served as a parental stress-reducing factor (Mikolajczak & Roskam, 2018). Furthermore, individual experiences of demands and resources can vary among parents, and high levels of stress and low levels of resources do not necessarily lead to parental burnout on their own (Mikolajczak & Roskam, 2020). According to BR2, parental burnout is a result of greater demands than resources chronically (Mikolajczak et al., 2019). The longer parents experience higher parenting demands in relation to available resources, the greater the risk for parental burnout (Mikolajczak & Roskam, 2018). Stressors experienced by an individual family member can contribute to stress within the broader family context. According to family stress theory (Patterson, 2002), a family's resources to manage stressors and the meaning a family gives stressful events can contribute to a crisis that alters, and potentially improves, family functioning. This model highlights the importance of social support and family system resources for positive family functioning and well-being. The COVID-19 pandemic may have introduced both stressors and family system resources for parents. For some families, the long-term nature of their parenting stressors may have provided new opportunities to support one another within the family. For example, some families’ routines suddenly changed with fewer work and school commutes, fewer extracurricular activities, more family time, and increased coparenting support (Bender et al., 2022; He et al., 2021; Mikolajczak & Roskam, 2020). Given the prolonged stressors and changes to many families’ daily lives due to COVID-19, it is important to examine the risk and protective factors for burnout that parents experienced during the second year of the pandemic. Risk and Protective Factors Associated with Parental Burnout Many parents experienced increased parental stress during the COVID-19 pandemic as well as stress due to the pandemic itself (Adams et al., 2021; Calvano et al., 2021). Therefore, both parental stress and COVID-19 stress may have contributed to parental burnout for parents. Parenting stressors can include providing physical care, emotional support, and financial support for children (Blanchard et al., 2021; Griffith, 2020; Pew Research Center, 2020), all of which may have changed for parents during the pandemic. A study conducted by Joyce (2022) in the United States of America during the first year of the pandemic found an association between parental stress and parental burnout. In a study conducted in Norway, parental stress significantly predicted parental burnout after controlling for insomnia, self-efficacy, parental satisfaction, metacognitions and unhelpful coping strategies (Skjerdingstad et al., 2021). In addition to parental stress, the pandemic itself may have also introduced additional stress in the form of concerns for physical health, safety, and pandemic-related changes in family life. For instance, concerns about COVID-19 among parents in the United States of America predicted greater parental burnout (Prikhidko et al., 2020). However, few studies have examined the effects of COVID-19 stress on parental burnout specifically. For example, one study found COVID-19 stress was associated with parental exhaustion during the lockdown in Italy (Marchetti et al., 2020). Another study reported lockdown measures during COVID-19 were associated with very small but significant changes in parental burnout during the pandemic compared to pre-pandemic (Le Vigouroux et al., 2022b). Thus, additional research is needed to understand the effects of parental stress and COVID-19 stress on parental burnout. In addition to risk factors, it is important to examine protective factors available to parents during the pandemic. The presence of a coparent may have provided support and stress relief for some parents. Coparenting refers to parents working collaboratively together to care for their child(ren) and the degree to which parents support or undermine one another in their role as parents (Feinberg, 2003). Coparenting support can reduce parenting stress when parents agree upon parenting practices, actively share parenting responsibilities, and value one another's contributions as coparents (Durtschi et al., 2017; Mikolajczak et al., 2018b). During the lockdown period in Italy, coparenting support was associated with lower levels of parental stress (Giannotti et al., 2021). Coparenting support was also associated with less COVID-19-related stress among mothers in North America (Pruett et al., 2021). Additionally, another study found cooperative coparenting mitigated the effects of parental stress on harsh parenting during the lockdown in New Zealand (McRae et al., 2021). However, few studies have provided empirical evidence for the association between coparenting support and parental burnout, and even fewer studies have examined this relationship during the COVID-19 pandemic. In one of the few studies examining this relationship during the pandemic, Bastiaansen et al. (2021) found cooperative coparenting buffered the effect of COVID-19 lockdown measures on parental burnout for fathers but not for mothers. Furthermore, Favez et al. (2022) found negative coparenting behaviors that exposed children to interparental conflict were associated with higher levels of parental burnout; however, endorsing the other partner's parenting was associated with lower parental burnout. Thus, emerging research suggests coparenting support predicts lower levels of parental burnout and may mitigate the effects of parental stress on burnout. The Current Study The COVID-19 pandemic introduced many stressors for parents that abruptly changed daily routines. As the pandemic entered the second year, experiencing longer-term stressors placed parents at an increased risk for parental burnout. At the same time, parents may no longer have had access to their support system due to public health mandates and concerns for safety. While many studies have explored associations between parental stress and parental burnout, few have examined coparenting support in relation to parental burnout during the pandemic. The pandemic accelerated growing awareness of the need to focus on parenting experiences and parental burnout within developmental psychology (Mikolajczak & Roskam, 2020). Year two of the pandemic presents an opportunity to explore and evaluate the associations among risk and protective factors for parental burnout in the context of global, chronic parenting stressors. In the current study, we examined the unique effects of parental stress, COVID-19 stress, and coparenting support on parental burnout. We hypothesized (a) parental stress and COVID-19 stress would be positively associated with parental burnout, (b) coparenting support would be negatively associated with parental burnout, and (c) coparenting support would moderate the relationship between parental stress and parental burnout. Method Participants One hundred fifty-five parents in the United States of America participated in this study, as part of a larger study of parenting experiences during the COVID-19 pandemic. Participants ranged in age from 18 to 69 years (M = 39.6, SD = 7.38; female = 94.8%). The majority of participants identified as White/European (80%), followed by those who identified as multiracial (6.5%), Asian/Asian American (5.2%), Latina/o/x (4.5%), African American/Black (0.6%), American Indian/Alaska Native (0.6%), and other (1.9%). A total of 86.4% of parents in this study reported they were married and 80.6% had an undergraduate degree or higher. Participants reported having a range of 1–5 children (Mchildren = 2, SD = 0.96; Mage = 7.83, SD = 5.19). For additional sociodemographic information, see Table 1. Table 1. Sociodemographic Information. Variable M (SD)/% Child age (in years) 7.83 (5.19) Parent age (in years) 39.6 (7.38) Child gender Female 46.6% Male 50.3% Parent gender Female 94.8% Male 4.5% Nonbinary 0.6% Relationship status Married 86.4% Divorced/separated 7.1% Single 3.9% Defacto (living with a long-term partner) 2.6% Parental status Single parent 5.8% Two or more parents in the same home (in a romantic relationship) 89% Co-parents living in different homes 3.9% Other 1.3% Race African American/Black 0.6% American Indian/Alaska native 0.6% Asian American/Asian 5.2% Latina/o/x 4.5% Multiracial 6.5% White/European 80% Other 1.9% Education Some elementary school 0.6% Some high school 1.9% Completed high school 10.3% Associate's degree 6.5% Undergraduate degree 39.4% Post-graduate degree 41.3% Annual income pre-COVID-19 < US$25,000 1.9% US$25,001–50,000 7.7% US$50,001–75,000 9.7% US$75,001–100,000 15.5% US$100,001–125,000 15.5% US$125,001–150,000 12.9% US$150,001–175,000 9% US$175,001–200,000 5.2% > US$200,000 18.7% Annual income during COVID-19 < US$25,000 2.6% US$25,001–50,000 8.4% US$51,001–75,000 9.7% US$75,001–100,000 19.4% US$100,001–125,000 11% US$125,001–150,000 15.5% US$150,001–175,000 8.4% US$175,001–200,000 4.5% > US$200,000 16.8% Area Rural/Country 7.1% Suburban 50.3% Urban/City 41.6% Region West (including Alaska and Hawaii) 63.9% Midwest 6.4% Southwest 9.7% Northeast 16.1% Southeast 3.9% Religion Agnostic 21.9% Atheist 4.5% Catholic 16.1% Evangelical 8.4% Jewish 4.5% Mormon 1.3% Muslim 0.6% Protestant 20.6% Other 18.7% Household COVID-19 diagnosis Yes 11.6% No 84.5% Measures Parental stress Parents completed the 18-item Parental Stress Scale (Berry & Jones, 1995) using a 5-point scale ranging from 1 (strongly disagree) to 5 (strongly agree). Sample item: “I feel overwhelmed by the responsibility of being a parent.” Raw scores of negatively worded items were reversed. The item scores were then summed, with higher scores indicating greater parental stress (α = 0.88). COVID-19 stress Parents completed the 36-item COVID Stress Scale (Taylor et al., 2020) using a 5-point scale ranging from 0 (not at all) to 4 (extremely). The measure consists of 5 subscales (danger and contamination fears, fears about economic consequences, xenophobia, compulsive checking and reassurance seeking, and traumatic stress symptoms). Sample item: “I had trouble concentrating because I kept thinking about the virus.” For the current study, all items were summed to create a total COVID-19 stress score, with higher scores indicating greater stress related to the COVID-19 pandemic (α = 0.93). Coparenting support Parents completed items of the Coparenting Relationship Scale (CRS) that corresponded to the coparenting support subscale (Feinberg et al., 2012). The CRS assesses four domains of coparenting (childrearing agreement, support and undermining, satisfaction with division of labor, and family management). We used the coparenting support subscale for this study, which consists of six items that assess a parent's perception of coparenting support they receive from a partner. Participants responded to questions using a 7-point scale ranging from 0 (not true of us) to 6 (very true of us). Items from the subscale are summed with higher scores indicating a greater sense of coparenting support (α = 0.92). Parental burnout Parents completed the 23-item Parental Burnout Assessment (PBA; Roskam et al., 2018) on the frequency of their feelings of burnout as a parent during COVID-19 using a 7-point scale ranging from 0 (never) to 6 (every day). The PBA assesses four key components of parental burnout: emotional exhaustion, emotional distancing from children, loss of pleasure in the parental role, and contrast with previous parental self. Items are summed to create a global burnout score for each participant, with higher scores indicating greater parental burnout. We did not have specific hypotheses related to the subscales; therefore, the global score for each participant was used for this study (α = 0.97). Sociodemographic items The following sociodemographic factors were included in this study for each participant: age, gender, race, relationship status, parental status (e.g., single parent, coparent in the same household), education level, household income before and during the pandemic, number of children, child age, child gender, location (e.g., urban), region of the country, and religion. The majority of participants in the current study reported no change in their household income during the pandemic (72.9%). Approximately 15% reported a decrease in household income and 7% reported an increase in household income. Due to the stress that COVID-19 infection in the household can add to parenting, participants were also asked to indicate if anyone in their household has, or has had COVID-19, at the time they completed the questionnaire. For additional details on these factors see Table 1. Procedures Data collection took place online using Qualtrics. Flyers containing information about the purpose of the study and procedures for participation were distributed to parenting groups on social media and organizations serving parents and families throughout the United States of America (e.g., parenting Facebook groups, neighborhood parenting groups). To provide consent and complete an anonymous online questionnaire, participants clicked on a link provided on the flyer. Data collection was completed between January 2021 and June 2021. Procedures were conducted in accordance with the APA Code of Ethics and the university institutional review board where the study was approved. Analytic Approach All statistical analyses were conducted in R (version 4.1.2). Listwise deletion was used to handle missing data. Prior to performing the main analyses, we tested the effect of participant gender on the key variables. No significant gender differences emerged among the variables (all p-values >.05). Descriptive statistics and zero-order correlations were conducted as preliminary analyses (see Table 2). Table 2. Means, Standard Deviations, and Correlations among Covariates, Stress, and Support Variables. Variable M SD Possible Range 1 2 3 4 5 6 7 8 9 1. Age 39.6 7.38 — — 2. Gender — — — 0.07 — 3. Number of Children 2 0.96 — 0.09 0.01 — 4. Change in Household Income −0.17 1.05 — 0.03 0.09 0.07 — 5. Household COVID-19 Diagnosis — — — 0.21* 0.12 0.02 0.10 — 6. Parental Stress 43.73 10.41 18–90 −0.03 −0.08 −0.10 0.03 0.00 — 7. COVID-19 Stress 34.71 19.18 0–144 −0.08 0.03 −0.09 −0.08 −0.13 0.16 — 8. Coparenting Support 5.45 1.48 0–6 −0.09 0.12 0.01 −0.02 −0.04 −0.18 −0.07 — 9. Parental Burnout 35.76 29.19 0–138 −0.09 0.02 0.02 0.04 0.04 0.72*** 0.19* −0.29*** — Note. Gender: 1 = male, 2 = female; Household COVID-19 diagnosis: 1 = yes, 2 = no. p < .05, ** p < .001. A hierarchical regression analysis was performed to evaluate the effects of risk and protective factors associated with parental burnout during the second year of the pandemic. In the first step, sociodemographic variables (i.e., age, gender, number of children, change in household income, and COVID-19 diagnosis in the household) were entered. Previous research suggests parental burnout is related to age (Le Vigouroux et al., 2022a; Woine et al., 2022), gender (Kerr et al., 2021), number of children in the household (Le Vigouroux & Scola, 2018), and change in household income (Griffith, 2020). In addition, knowing someone diagnosed with COVID-19 in a close setting (e.g., a family member or a close friend) is associated with greater psychological distress (Tanoue et al., 2020). Hence, these sociodemographic factors were included as covariates of parental burnout. Each risk and protective factor were added one at a time to the regression model to evaluate the contribution of each variable in terms of explained variance in parental burnout. Then each model was compared to the previous model to determine if it explained significantly more variance in parental burnout. The two risk factors, parental stress and COVID-19 stress, were entered in steps 2 and 3. The protective factor, coparenting support, was added in step 4. Lastly, the interaction between risk and protective factors was examined in the final step. Results Means, standard deviations, and correlations are presented in Table 2. With regard to the possible range of scores for each scale, the mean scores for participants in this sample were below the midpoint for parental stress (M = 43.73, SD = 10.41), and near the bottom quartile for both COVID-19 stress (M = 34.71, SD = 19.18) and parental burnout (M = 35.76, SD = 29.19). However, the mean for coparenting support was at the upper end of the possible range (M = 5.45, SD = 1.48). As hypothesized, parental stress (r = 0.72, p < .001) and COVID-19 stress (r = 0.19, p = .03) were positively correlated with parental burnout, and coparenting support (r = −0.29, p = .003) was negatively correlated with parental burnout. No sociodemographic variables were significantly correlated with parental burnout. Predictors of Parental Burnout Hierarchical regression analyses were conducted to test the unique effects of parental stress, COVID-19 stress, and coparenting support on parental burnout. Results from the regressions are presented in Table 3. Sociodemographic factors were entered in the first step as covariates. Age, gender, number of children in the household, change in household income, and having someone in the household diagnosed with COVID-19 did not significantly predict parental burnout, R2 = 0.01, F(5, 85) = 0.18, p = ns. Table 3. Hierarchical Regression Model of the Predictors of Parental Burnout. Variable B 95% CI for B SE B β R2 ΔR2 LL UL Step 1 0.01 0.01 Constant 56.06* 8.19 103.92 24.07 Age −0.29 −1.21 0.62 0.46 −0.07 Gender −0.71 −25.86 24.43 12.65 −0.01 Number of children −1.80 −9.02 5.42 3.63 −0.05 Change in income 0.85 −5.51 7.20 3.20 0.03 Household COVID-19 Diagnosis −1.87 −20.18 16.43 9.20 −0.02 Step 2 0.55 0.54* Constant 49.15 16.63 81.67 16.35 Age −0.58 −1.20 0.04 0.31 −0.14 Gender 11.16 −6.07 28.38 8.66 0.10 Number of Children 2.08 −2.88 7.04 2.50 0.06 Change in Income −0.73 −5.05 3.60 2.17 −0.02 Household COVID-19 Diagnosis −2.96 −15.38 9.47 6.25 −0.04 Parental Stress 2.20* 1.76 2.63 0.22 0.75* Step 3 0.55 0.00 Constant 46.95 11.61 82.28 17.77 Age −0.58 −1.20 0.05 0.31 −0.14 Gender 10.61 −7.03 28.25 8.87 0.09 Number of Children 2.19 −2.84 7.22 2.53 0.07 Change in Income −0.71 −5.06 3.64 2.19 −0.02 Household COVID-19 Diagnosis −2.47 −15.31 10.37 6.45 0.03 Parental Stress 2.18* 1.73 2.63 0.23 0.75*** COVID-19 Stress 0.04 −0.19 0.27 0.12 0.03 Step 4 0.58 0.03* Constant 47.66** 13.33 82 17.26 Age −0.64* −1.25 −0.03 0.31 −0.16* Gender 12.59 −4.62 29.81 8.65 0.11 Number of Children 2.24 −2.65 7.13 2.46 0.07 Change in Income −0.71 −4.93 3.52 2.12 −0.02 Household COVID-19 Diagnosis −2.48 −14.95 10 6.27 −0.03 Parental Stress 2.12* 1.69 2.56 0.22 0.73* COVID-19 Stress 0.03 −0.19 0.26 0.11 0.02 Coparent Support −3.31* −6.02 −0.61 1.36 −0.18* Note. Gender: 1 = male, 2 = female; Household COVID-19 Diagnosis: 1 = yes, 2 = no; CI = confidence interval; LL = lower limit; UL = upper limit. p < .05, p < .01, **p < .001. Next, parental stress, COVID-19 stress, and coparenting support were entered into the model one at a time, controlling for sociodemographic factors. Each model accounted for a significant increase in explained variance for parental burnout, with the exception of model 3 (see Table 3). Model 4 explored the unique effects of parental stress, COVID-19 stress, and coparenting support on parental burnout, R2 = 0.58, F(8, 82) = 14.19, p < .001. Parental age (β = −0.16, t = −2.10, p = .04, 95% CI [−1.25, −0.03]), parental stress (β = 0.73, t = 9.64, p < .001, 95% CI [1.69, 2.56]), and coparenting support (β = −0.18, t = −2.44, p = .02, 95% CI [−6.02, −0.61]) each significantly predicted parental burnout while controlling for the remaining variables in the model. Among participants in this sample, increased parental age predicted less parental burnout. Examining the stress and support variables, higher parental stress predicted greater parental burnout. Conversely, higher coparenting support predicted lower levels of parental burnout. Thus, parental stress and coparenting support during the COVID-19 pandemic predicted parental burnout while stress related to COVID-19 did not. To test the moderating effect of coparenting support, the interaction between parental stress and coparenting support was added to the model. Although the model was statistically significant, F(9, 81) = 12.59, p < .001, adding the interaction did not significantly increase the variance explained. Additionally, the interaction was not statistically significant, suggesting coparenting did not moderate the relationship between parental stress and parental burnout. Discussion Drawing upon BR2 (Mikolajczak et al., 2019) and family stress theory (Patterson, 2002), this study explored risk and protective factors associated with parental burnout during the second year of the COVID-19 pandemic in the United States of America. The first hypothesis that parental stress would predict parental burnout was supported. This finding is consistent with studies published earlier in the pandemic, which found parents experienced moderate to high levels of stress during the pandemic (Calvano et al., 2021; Sahithya et al., 2020). Likewise, parents reported they felt more stressed and burned out in their role as a parent (Le Vigouroux et al., 2022b). This finding also lends support to other parenting studies conducted during the pandemic, which similarly found parental stress predicted parental burnout (Skjerdingstad et al., 2021). The finding that parents experienced parenting demands and stressors during the pandemic that exceeded their resources and contributed to parental burnout is also consistent with family stress theory (Patterson, 2002). Due to the additional stress and demands parents experienced during COVID-19, we hypothesized stress directly related to COVID-19 (e.g., health concerns) would predict parental burnout over and above parental stress. This hypothesis was not supported. Participants in this sample reported levels of COVID-19 stress at the lower range of the scale and consistent with those reported in other studies using this measure with adults (Asmundson et al., 2020; Carlander et al., 2022). It is possible that stress due to concerns about COVID-19 may contribute to parental burnout in other samples, particularly among parents who experience higher levels of COVID-related stress. Although they did not include parental burnout, Adams et al. (2021) found worry and anxiety related to COVID-19 were common stressors for parents who experienced moderate to high levels of stress during the pandemic. In line with family stress theory, parents in this study may have experienced stress due to the pandemic; however, it may not have reached a level that exceeded their resources to manage the stress within their family. Other proximal stressors, such as parental stress, may be more prominent in predicting parental burnout. Given the important role parenting resources and support can play in mitigating family stress, we expected coparenting support to be negatively associated with parental burnout. This hypothesis was supported. This finding is consistent with BR2 and supports previous findings demonstrating coparenting support is a protective factor against parental burnout (Mikolajczak & Roskam, 2018). Few studies have explored the effect of coparenting support on parental burnout (Bastiaansen et al., 2021), and even less is known regarding the effect of coparenting support on parental burnout during COVID-19. Thus, the current finding is important in the context of the ongoing COVID-19 pandemic. It is important to note participants in this sample reported high levels of coparenting support. Parents in this study were moderately stressed as parents and felt highly supported. Moreover, few parents experienced the loss of childcare or household income, both of which have been associated with parental burnout (Joyce, 2022; Swit & Breen, 2022). This may have contributed to the majority of the sample scoring below the cutoffs used in previous studies for parental burnout (Roskam et al., 2021; Roskam et al., 2018). Nevertheless, it is important to identify potential risks for burnout among parents who have not yet reached the cutoff point. Finally, we tested the moderating effect of coparenting support. The findings were not statistically significant, suggesting coparenting support did not buffer against the negative effect of parental stress on parental burnout in the current study. Although previous studies have found coparenting support protected against parental burnout (Mikolajczak & Roskam, 2018), findings on parenting during the COVID-19 pandemic were mixed. For example, in a study conducted by Bastiaansen et al. (2021) the relationship between pandemic restrictions and parental burnout was not impacted by coparenting in general. However, coparenting did mitigate the impact of the restrictions on parental burnout among fathers. Thus, their findings suggest coparenting support may offer protection against parental burnout, and they also point to an area for future research as the effects may differ for fathers and mothers. It is important to note that parental age was negatively associated with parental burnout in this sample during the second year of the COVID-19 pandemic. This finding is consistent with those from studies of parenting in the early stages of the pandemic (Skjerdingstad et al., 2021; Sorkkila & Aunola, 2021; Woine et al., 2022). It could be that older age as a parent offered certain protective factors, such as increased parenting experience (Woine et al., 2022), that helped parents cope with parenting stressors as pandemic-related changes continued into the second year. As mentioned previously, many parents in this study did not meet the cutoff for parental burnout used by Roskam et al. (2021), which requires a score of 92 or above. The 6% of the parents who met the cutoff in this sample is within the 5–20% range reported in pre-pandemic studies (Roskam et al., 2018; Séjourné et al., 2018). Our finding is also consistent with other studies reporting similar or lower levels of burnout among parents during COVID-19 (Bastiaansen et al., 2021; Le Vigouroux et al., 2022b; Swit & Breen, 2022; Woine et al., 2022). Although several studies have reported increases in parenting stress and stress due to the pandemic, COVID-19 stress did not significantly predict parental burnout among participants in this study. Furthermore, parents in the current study reported low levels of stress related to COVID-19. It is possible that worries and concerns about contracting the virus waned and other parenting stressors became more salient during the second year of the pandemic, especially as vaccination distribution began among adults. While COVID-19 introduced new stressors for parents and families globally, stress directly related to COVID-19 did not contribute to burnout for parents in this study. Rather, parental stress and coparenting support were both important risk and protective factors for parental burnout respectively. Importantly, these factors are also both associated with parental burnout in non-pandemic times as well. The current findings contribute to the broader literature on parental burnout and further highlight the significance of parental stress and support. Thus, the risk and protective factors parents experienced during the pandemic may have similar impacts on parental burnout during other stressful periods as well. The current findings contribute to the broader literature on parental burnout and further highlight the significance of parental stress and support. Implications and Future Directions Minimizing and managing parental stress is critical for parental and family well-being, especially during stressful periods due to the increased risk for parental burnout. It is important to view parental stress as a serious concern that needs to be balanced with adequate resources. According to BR2, even when faced with significant parenting demands, if there are sufficient resources to balance and meet the demands, parental burnout may not occur. Clinicians working with parents and families may want to focus on providing individual parenting services to reduce parental stress as well as family services to improve coparenting support. Clinician therapeutic support may offer important benefits and help reduce parental burnout (Brianda et al., 2020a). When experiencing stressors, such as a pandemic, or for clients who cannot attend therapy in-person, teletherapy may present clinicians with an opportunity to provide support for parents experiencing novel or chronic stressors (Milot, 2021). Research on parental burnout is relatively new but has grown internationally in recent years (Aguiar et al., 2021; Aunola et al., 2021; Chen et al., 2022; Mikolajczak et al., 2019; van Bakel et al., 2018). Future studies could identify risk factors contributing to parental burnout and explore the mechanisms through which they exert their influence. Several studies conducted during the COVID-19 pandemic have provided initial information to better understand sociodemographic differences in experiences of parental burnout (Fontanesi et al., 2020; Le Vigouroux et al., 2022b; Skjerdingstad et al., 2021). However, a study by Woine et al. (2022) found that sociodemographic and situational variables (e.g., teleworking, homeschooling) explained a very small proportion of the variance in parental burnout. In contrast, parental cognitive appraisals of their parenting during the pandemic were primary contributors to parental burnout. Additional research is needed to further explore how parental stress and other factors contribute to parental burnout, for whom, and under what conditions. Longitudinal studies could also explore the impact of parental stress and coparenting, especially the trajectories of parental burnout and the effects of burnout on families over time (Griffith, 2020). Not all parents who lack coparenting or social support develop parental burnout. Understanding how and when the imbalance of risk factors and resources leads to parental burnout is important to better support parents, children, and families (Mikolajczak & Roskam, 2020). Lastly, it is important to explore the development and impact of parental burnout among diverse cultures and family structures. Thus, future studies could build upon existing research to better understand both the risk and protective factors contributing to parental burnout in diverse parenting contexts (Roskam et al., 2020, 2022). Limitations The present findings must be interpreted in light of several limitations. First and foremost, the small sample size in this study precluded further analyses involving additional variables. To understand the effect of chronic and acute parental stress on burnout, future research should examine potential moderators (e.g., parent gender, social support; Etzion, 1984; Roskam & Mikolajczak, 2020) and mediators (e.g., emotional regulation; Gomes et al., 2013), alongside sociodemographic variables. Relatedly, researchers could further investigate how parental stress and burnout might affect child development. Second, the present study involved predominantly White, educated mothers residing in the western United States, whose families did not experience major financial loss or job loss. Experiencing a major decrease in household income was associated with parental burnout, while loss of paid work was unrelated to parental burnout, during the COVID-19 lockdown (Swit & Breen, 2022). Hence, future research should include a more diverse sample at varying levels of socioeconomic status before versus during COVID-19 or other major life events. Third, at the time of data collection, many parents were working from home and their children were schooling from home, depending on the lockdown and public health mandates across the United States of America. The changes in work and school settings might have served as third variable affecting parental stress, coparenting support, and burnout during the pandemic. Fourth, the study included self-report, which could lead to method bias (Podsakoff et al., 2012). Future research should use a multi-method, multi-informant approach by recruiting multiple reporters and collecting physiological data of stress (e.g., stress hormones over time) to reduce the method bias. Finally, the present study involved cross-sectional data, which precluded us from drawing conclusions on the directionality of effects. It is also uncertain whether stress and burnout are related over time. Hence, longitudinal studies merit future investigation. Conclusion The COVID-19 pandemic introduced new challenges in parenting. For many parents, stressors in parenting and childcare continued during the second year of the pandemic. In the current study, parenting stress was a major risk factor for parental burnout while coparenting support was negatively associated with parental burnout. Stress directly related to the pandemic did not uniquely contribute to parental burnout. Although many parents experienced concerns about COVID-19, stressors directly related to the complex activity of parenting itself appear to be a more important risk factor related to parental burnout. Addressing parental burnout is important, not only to prioritize parental mental health, but also due to the effects parental burnout can have on children and families. Taking a lifespan approach to human development, and understanding the experiences and needs of parents is a critical way to support family well-being. Authors’ Note: We would like to thank the parents who participated in this study and shared their time and experiences during the COVID-19 pandemic. The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The authors received no financial support for the research, authorship, and/or publication of this article. ORCID iD: Jenny Lee Vaydich https://orcid.org/0000-0003-2278-9308 ==== Refs References Abidin R. R. (1990). Parenting stress index manual. Pediatric Psychology Press. Adams E. L. Smith D. Caccavale L. J. Bean M. K . (2021) Parents are stressed! Patterns of parent stress across COVID-19. Frontiers in Psychiatry, 12 , Article 626456. 10.3389/fpsyt.2021.626456 Aguiar J. Matias M. Braz A. C. César F. Coimbra S. Gaspar M. F. Fontaine A. M. (2021). Parental burnout and the COVID-19 pandemic: How Portuguese parents experienced lockdown measures. Family Relations, 70 (4 ), 927–938. 10.1111/fare.12558 34548725 Asmundson G. J. G. Paluszek M. M. Landry C. A. Rachor G. S. McKay D. Taylor S . (2020). Do pre-existing anxiety-related and mood disorders differentially impact COVID-19 stress responses and coping? Journal of Anxiety Disorders, 74 , Article 102271. 10.1016/j.janxdis.2020.102271 Aunola K. Sorkkila M. Tolvanen A. Tassoul A. Mikolajczak M. Roskam I. (2021). Development and validation of the brief parental burnout scale (BPBS). Psychological Assessment, 33 (11 ), 1125–1137. 10.1037/pas0001064 34516161 Bastiaansen C. Verspeek E. van Bakel H. (2021). Gender differences in the mitigating effect of co-parenting on parental burnout: The gender dimension applied to COVID-19 restrictions and parental burnout levels. Social Sciences, 10 (4 ), 127. Article 127. 10.3390/socsci10040127 Bender S. Brown K. S. Hensley Kasitz D. L. Vega O. (2022). Academic women and their children: Parenting during COVID-19 and the impact on scholarly productivity. Family Relations, 71 (1 ), 46–67. 10.1111/fare.12632 Berry J. O. Jones W. H. (1995). The parental stress scale: Initial psychometric evidence. Journal of Social and Personal Relationships, 12 (3 ), 463–472. 10.1177/0265407595123009 Blanchard M. A. Roskam I. Mikolajczak M. Heeren A . (2021). A network approach to parental burnout. Child Abuse & Neglect, 111 , Article 104826. 10.1016/j.chiabu.2020.104826 Brianda M. E. Roskam I. Mikolajczak M . (2020b). Hair cortisol concentration as a biomarker of parental burnout. Psychoneuroendocrinology, 117 , Article 104681. 10.1016/j.psyneuen.2020.104681 Brianda M. E. Roskam I. Mikolajczak M. (2020b). Hair cortisol concentration as a biomarker of parental burnout. Psychoneuroendocrinology, 117 , 104681, Article 104681. 10.1016/j.psyneuen.2020.104681 32417622 Calvano C. Engelke L. Di Bella J. Kindermann J. Renneberg B. Winter S. M. (2022). Families in the COVID-19 pandemic: Parental stress, parent mental health and the occurrence of adverse childhood experiences—results of a representative survey in Germany. European Child & Adolescent Psychiatry, 31 (7 ), 1–13. 10.1007/s00787-021-01739-0 Carlander A. Lekander M. Asmundson G. J. G. Taylor S. Olofsson Bagge R. Lindqvist Bagge A. S. (2022). COVID-19 related distress in the Swedish population: Validation of the Swedish version of the COVID Stress Scales (CSS). PLoS One, 17 (2 ), e0263888. Article e0263888. 10.1371/journal.pone.0263888 35157739 Chen M. Bai Y. Fu M. Huang N. Ahmed F. Shahid M. Wang X. Liu C. Feng X. L. Guo J . (2022). The associations between parental burnout and mental health symptoms among Chinese parents with young children during the COVID-19 pandemic. Frontiers in Psychiatry, 13 , Article 819199. 10.3389/fpsyt.2022.819199 Dawes J. May T. McKinlay A. Fancourt D. Burton A. (2021). Impact of the COVID-19 pandemic on the mental health and wellbeing of parents with young children: A qualitative interview study. BMC Psychology, 9 (1 ), 194. Article 194. 10.1186/s40359-021-00701-8 34911570 Durtschi J. A. Soloski K. L. Kimmes J. (2017). The dyadic effects of supportive coparenting and parental stress on relationship quality across the transition to parenthood. Journal of Marital and Family Therapy, 43 (2 ), 308–321. 10.1111/jmft.12194 27701778 Etzion D. (1984). Moderating effect of social support on the stress–burnout relationship. Journal of Applied Psychology, 69 (4 ), 615–622. 10.1037/0021-9010.69.4.615 6511711 Favez N. Max A. Bader M. Tissot H . (2022). When not teaming up puts parents at risk: Coparenting and parental burnout in dual-parent heterosexual families in Switzerland. Family Process, 00 , 1– 15. 10.1111/famp.12777 Feinberg M. E. (2003). The internal structure and ecological context of coparenting: A framework for research and intervention. Parenting: Science and Practice, 3 (2 ), 95–132. 10.1207/S15327922PAR0302_01 21980259 Feinberg M. E. Brown L. D. Kan M. L. (2012). A multi-domain self-report measure of coparenting. Parenting: Science & Practice, 12 (1 ), 1–21. 10.1080/15295192.2012.638870 23166477 Fontanesi L. Marchetti D. Mazza C. Di Giandomenico S. Roma P. Verrocchio M. C. (2020). The effect of the COVID-19 lockdown on parents: A call to adopt urgent measures. Psychological Trauma: Theory, Research, Practice, and Policy, 12 (S1 ), S79–S81. 10.1037/tra0000672 32525382 Frankel L. A. Kuno C. B. Sampige R . (2021). The relationship between COVID-related parenting stress, nonresponsive feeding behaviors, and parent mental health. Current Psychology, 1–12. 10.1007/s12144-021-02333-y Giannotti M. Mazzoni N. Bentenuto A. Venuti P. de Falco S. (2022). Family adjustment to COVID-19 lockdown in Italy: Parental stress, coparenting, and child externalizing behavior. Family Process, 61 (2 ), 745–763. 10.1111/famp.12686 34195986 Gomes A. R. Faria S. Gonçalves A. M. (2013). Cognitive appraisal as a mediator in the relationship between stress and burnout. Work & Stress, 27 (4 ), 351–367. 10.1080/02678373.2013.840341 Griffith A. K. (2020). Parental burnout and child maltreatment during the COVID-19 pandemic. Journal of Family Violence, 37 (5 ), 725–731. 10.1007/s10896-020-00172-2 32836736 Hausman E. M. Black S. R. Bromet E. Carlson G. Danzig A. Kotov R. Klein D. N. (2020). Reciprocal effects of maternal and child internalizing symptoms before and after a natural disaster. Journal of Family Psychology, 34 (7 ), 836–845. 10.1037/fam0000653 32324018 He M. Cabrera N. Renteria J. Chen Y. Alonso A. McDorman S. A. Kerlow M. A. Reich S. M . (2021). Family functioning in the time of COVID-19 among economically vulnerable families: Risks and protective factors. Frontiers in Psychology, 12 , Article 730447. 10.3389/fpsyg.2021.730447 Joyce A . (2022). Controlling the uncontrollable: Stress, burnout, and parenting during a pandemic. The Family Journal. 10.1177/10664807221079289 Kerr M. L. Rasmussen H. F. Fanning K. A. Braaten S. M. (2021). Parenting during COVID-19: A study of parents’ experiences across gender and income levels. Family Relations, 70 (5 ), 1327–1342. 10.1111/fare.12571 34548726 Le Vigouroux S. Charbonnier E. Scola C. (2022a). Profiles and age-related differences in the expression of the three parental burnout dimensions. European Journal of Developmental Psychology, 1–20. 10.1080/17405629.2021.1990749 Le Vigouroux S. Lebert-Charron A. Wendland J. Boujut E. Scola C. Dorard G. (2022b). COVID-19 and parental burnout: Parents locked down but not more exhausted. Journal of Family Issues, 43 (7 ), 1705–1720. 10.1177/0192513X211030038 Le Vigouroux S. Scola C. (2018). Differences in parental burnout: Influence of demographic factors and personality of parents and children. Frontiers in Psychology, 9 , Article 887. 10.3389/fpsyg.2018.00887 Marchetti D. Fontanesi L. Mazza C. Di Giandomenico S. Roma P. Verrocchio M. C. (2020). Parenting-related exhaustion during the Italian COVID-19 lockdown. Journal of Pediatric Psychology, 45 (10 ), 1114–1123. 10.1093/jpepsy/jsaa093 33068403 McRae C. S. Overall N. C. Henderson A. M. E. Low R. S. T. Chang V. T. (2021). Parents’ distress and poor parenting during a COVID-19 lockdown: The buffering effects of partner support and cooperative coparenting. Developmental Psychology, 57 (10 ), 1623–1632. 10.1037/dev0001207 34807685 Mikolajczak M. Brianda M. E. Avalosse H. Roskam I . (2018a). Consequences of parental burnout: Its specific effect on child neglect and violence. Child Abuse & Neglect, 80 , 134–145. 10.1016/j.chiabu.2018.03.025 29604504 Mikolajczak M. Gross J. J. Roskam I. (2019). Parental burnout: What is it, and why does it matter? Clinical Psychological Science, 7 (6 ), 1319–1329. 10.1177/2167702619858430 Mikolajczak M. Raes M. E. Avalosse H. Roskam I . (2018b). Exhausted parents: Sociodemographic, child-related, parent-related, parenting and family-functioning correlates of parental burnout. Journal of Child and Family Studies, 27 (2 ), 602–614. 10.1007/s10826-017-0892-4 Mikolajczak M. Roskam I . (2018). A theoretical and clinical framework for parental burnout: The Balance Between Risks and Resources (BR2). Frontiers in Psychology, 9 , Article 886. 10.3389/fpsyg.2018.00886 Mikolajczak M. Roskam I. (2020). Parental burnout: Moving the focus from children to parents. New Directions for Child and Adolescent Development, 2020 (174 ), 7–13. 10.1002/cad.20376 Milot M . (2021). Video-based counseling shifts to the mainstream. Journal of Employee Assistance. http://hdl.handle.net/10713/14311 Palacios Cruz M. Santos E. Velázquez Cervantes M. A. León Juárez M. (2021). COVID-19, a worldwide public health emergency. Revista Clinica Espanola, 221 (1 ), 55–61. 10.1016/j.rceng.2020.03.001 33998479 Patterson J. M. (2002). Integrating family resilience and family stress theory. Journal of Marriage and Family, 64 (2 ), 349–360. 10.1111/j.1741-3737.2002.00349.x Pew Research Center (2020). About half of lower income Americans report household wage or job loss due to COVID-19. Retrieved from https://www.pewresearch.org/social-trends/2020/04/21/about-half-of-lower-income-americans-report-household-job-or-wage-loss-due-to-covid-19/ Podsakoff P. MacKenzie S. Podsakoff N. (2012). Sources of method bias in social science research and recommendations on how to control it. Annual Review of Psychology, 63 (1 ), 539–569. 10.1146/annurev-psych-120710-100452 Posel D. Oyenubi A. Kollamparambil U. (2021). Job loss and mental health during the COVID-19 lockdown: Evidence from South Africa. PloS One, 16 (3 ), e0249352. Article e0249352. 10.1371/journal.pone.0249352 33784339 Prikhidko A. Long H. Wheaton M. G . (2020). The effect of concerns about COVID-19 on anxiety, stress, parental burnout, and emotion regulation: The role of susceptibility to digital emotion contagion. Frontiers in Public Health, 8 , Article 567250. 10.3389/fpubh.2020.567250 Prime H. Wade M. Browne D. T. (2020). Risk and resilience in family well-being during the COVID-19 pandemic. American Psychologist, 75 (5 ), 631–643. 10.1037/amp0000660 32437181 Pruett M. K. Alschech J. Saini M. (2021). The impact of coparenting on mothers’ COVID-19-related stressors. Social Sciences, 10 (8 ), 311. Article 311. 10.3390/socsci10080311 Rao N. Fisher P. A. (2021). The impact of the COVID-19 pandemic on child and adolescent development around the world. Child Development, 92 (5 ), e738–e748. 10.1111/cdev.13653 34569058 Roskam I. Aguiar J. Akgun E. Arikan G. Artavia M. Avalosse H. Aunola K. Bader M. Bahati C. Barham E. J. Besson E. Beyers W. Boujut E. Brianda M. E. Brytek-Matera A. Carbonneau N. César F. Chen B.-B. Dorard G. , … & Mikolajczak M. (2021). Parental burnout around the globe: A 42-country study. Affective Science, 2 (1 ), 58–79. 10.1007/s42761-020-00028-4 33758826 Roskam I. Brianda M. E. Mikolajczak M . (2018). A step forward in the conceptualization and measurement of parental burnout: The Parental Burnout Assessment (PBA). Frontiers in Psychology, 9 , Article 758. 10.3389/fpsyg.2018.00758 Roskam I. Gallée L. Aguiar J. Akgun E. Arena A. Arikan G. Aunola K. Bader M. Barham E. J. Besson E. Beyers W. Boujut E. Brianda M. E. Brytek-Matera A. Carbonneau N. César F. Chen B.-B. Dorard G. dos Santos Elias L. C. Mikolajczak M. (2022). Gender equality and maternal burnout: A 40-country study. Journal of Cross-Cultural Psychology, 53 (2 ), 157–178. 10.1177/00220221211072813 Roskam I. Mikolajczak M . (2020). Gender differences in the nature, antecedents and consequences of parental burnout. Sex Roles, 83 (7-8 ), 485–498. 10.1007/s11199-020-01121-5 Sahithya B. R. Kashyap R. S. Roopesh B. N. (2020). Perceived stress, parental stress, and parenting during COVID-19 lockdown: A preliminary study. Journal of Indian Association for Child and Adolescent Mental Health, 16 (4 ), 44–63. doi:10.1177/0973134220200404 Séjourné N. Sanchez-Rodriguez R. Leboullenger A. Callahan S. (2018). Maternal burn-out: An exploratory study. Journal of Reproductive and Infant Psychology, 36 (3 ), 276–288. 10.1080/02646838.2018.1437896 29517340 Skjerdingstad N. Johnson M. S. Johnson S. U. Hoffart A. Ebrahimi O. V . (2021). Parental burnout during the COVID-19 pandemic. Family Process, 00 , 1– 15. 10.1111/famp.12740 Sorkkila M. Aunola K. (2021). Resilience and parental burnout among Finnish parents during the COVID-19 pandemic: Variable and person-oriented approaches. The Family Journal, 30 (2 ), 139–147. 10.1177/10664807211027307 Swit C. S. Breen R . (2022). Parenting during a pandemic: Predictors of parental burnout. Journal of Family Issues. 10.1177/0192513X211064858 Tanoue Y. Nomura S. Yoneoka D. Kawashima T. Eguchi A. Shi S. Harada N. Miyata H . (2020). Mental health of family, friends, and co-workers of COVID-19 patients in Japan. Psychiatry Research, 291 , Article 113067. 10.1016/j.psychres.2020.113067 Taylor S. Landry C. A. Paluszek M. M. Fergus T. A. McKay D. Asmundson G. J . (2020). Development and initial validation of the COVID Stress Scales. Journal of Anxiety Disorders, 72 , Article 102232. 10.1016/j.janxdis.2020.102232 van Bakel H. Hall R. Bastiaansen C. Schwabe I. Roskam I. Mikolajczak M. (in press). Tough or easy? Prevalence rates of parental burnout around the world before and during the COVID-19 pandemic. van Bakel H. Van Engen M. Peters P. (2018). Validity of the parental burnout inventory among Dutch employees. Frontiers in Psychology, 23 , Article 697. 10.3389/fpsyg.2018.00697 Woine A. Mikolajczak M. Gross J. van Bakel H. Roskam I. (2022). The role of cognitive appraisals in parental burnout: A preliminary analysis during the COVID-19 quarantine. Current Psychology, 1–14. 10.1007/s12144-021-02629-z
PMC009xxxxxx/PMC9465058.txt	==== Front Fam J Alex Va Fam J Alex Va TFJ sptfj Family Journal (Alexandria, Va.) 1066-4807 1552-3950 SAGE Publications Sage CA: Los Angeles, CA 10.1177/10664807221124251 10.1177_10664807221124251 COVID-19 Pandemic COVID-19-Related Stress and Resilience Resources: A Comparison Between Adoptive and non-Adoptive Mothers https://orcid.org/0000-0003-2379-6227 Ferrari Laura 1 Canzi Elena 1 Barni Daniela 2 Ranieri Sonia 3 Danioni Francesca Vittoria 4 La Fico Giuliana 4 Rosnati Rosa 1 1 Department of Psychology, Family Studies and Research University Centre, 9371 Università Cattolica del Sacro Cuore , Milan, Italy 2 Department of Human and Social Sciences, 18953 Università degli Studi di Bergamo , Bergamo, Italy 3 Department of Psychology, Family Studies and Research University Centre, 9371 Università Cattolica del Sacro Cuore , Piacenza, Italy 4 Family Studies and Research University Centre, 9371 Università Cattolica del Sacro Cuore , Milan, Italy Laura Ferrari, Department of Psychology, Family Studies and Research University Centre, Università Cattolica del Sacro Cuore, Largo Gemelli 1, 20123 Milan, Italy. Email: [email protected] 9 9 2022 7 2023 9 9 2022 31 3 454463 © The Author(s) 2022 2022 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. Despite an increasing interest in how adoptive parents deal with situations appraised as stressful, there is a lack of research regarding adoptive parents’ adjustment to the challenges posed by the prolonged COVID-19 pandemic. The current study explores similarities and differences between adoptive and non-adoptive mothers in terms of risks (i.e., COVID-19-related stress) and individual (i.e., sense of coherence [SOC]), couple (i.e., partner's support), parent–child (i.e., parent–child relationship satisfaction), and social (i.e., friends’ support) resources in the face of the prolonged COVID-19 pandemic. Specifically, the present study was aimed at predicting which variables discriminate more effectively between the two groups. Participants were 445 Italian mothers (40.9% adoptive mothers), who were asked to fill in an anonymous online survey between May 2021 and October 2021. Results showed that adoptive and non-adoptive mothers reported different resilience resources to face the stressors posed by the health emergency. Specifically, COVID-19 traumatic stress symptoms, parent–child relationship satisfaction, and SOC were found to contribute most in discriminating between the two groups. Findings are discussed in relation to future research developments and practical implications. adoptive and non-adoptive mothers COVID-19-related stress sense of coherence partner’s and friends’ support parent–child relationship satisfaction typesetterts19 ==== Body pmcThe early stage of COVID-19 pandemic posed unique risks in terms of parental stress and strongly challenged parents’ personal and relational well-being. As stated in the review by Brooks et al. (2020), research on the reactions to former epidemics has already shown that having children is a key factor associated with higher levels of stress and higher short- and long-term risks for mental health during lockdown than non-having children (Liu et al., 2012; Nickell et al., 2004; Taylor et al., 2008). The psychosocial literature on COVID-19 has confirmed these findings. Since the very beginning of this health emergency, parents showed an increase in mental health problems such as anxiety, depression, and post-traumatic symptoms (Adams et al., 2021; Brown et al., 2020; Herbert et al., 2020; Spinelli et al., 2020; Twenge & Joiner, 2020). They reported to experience fear and uncertainty, family life routines’ disruptions, caregiving burnout, financial worries, work–family stress, and lack of social support (Calarco et al., 2020; Choi et al., 2020; Lei et al., 2020; Weaver & Swank, 2021; Zhang et al., 2020). Moreover, given the prolonged pandemic and the persistency of these several demands, many parents are likely to experience chronic stress, leading to more emotional overloading, with mothers being more challenged in terms of psychological well-being, caregiving burnout, and family–work stress (e.g., Petts et al., 2021). This is particularly true for parents of more vulnerable children such as children with special educational needs and/or acute or chronic diseases (Tso et al., 2022). Among vulnerable groups, adoptive families should be specifically considered. Indeed, adoptive children experienced early adversities and struggled with traumas and usually had a higher risk to show emotional and behavioral problems as well as learning difficulties compared to their non-adopted peers (e.g., Askeland et al., 2018; Barroso et al., 2017; Behle & Pinquart, 2016; van IJzendoorn & Juffer, 2006) that may have exposed them to greater challenges during the pandemic (e.g., Goldberg et al., 2021). Adoptive parents, in turn, may have faced additional stressors, too. Literature in the COVID-19 era has so far mainly focused on parents with biological children. Few studies included families that have faced nonnormative transitions, such as adoptive parents (e.g., Goldberg et al., 2021). Thus, there is a lack of knowledge about psychological adjustment to the pandemic among adoptive parents and even less is known about the differences between adoptive and non-adoptive parenthood in the COVID-19 context. The main aim of the current study is therefore to fill this gap of knowledge. The focus on adoptive parents could be of great interest due to the specific characteristics of this study population. Adoptive parents have faced additional challenges related to the adoption process likely to make them more vulnerable to stressful events: they have usually faced infertility (Cohen et al., 1993; Daniluk & Hurtig-Mitchell, 2003), they have become parents rather late in life (Ceballo et al., 2004), they have often coped with children who are emotionally and behaviorally difficult due to early adversities (e.g., Askeland et al., 2018; Barroso et al., 2017; van IJzendoorn & Juffer, 2006), and they have managed uncertainty and lack of control over the adoption process. However, despite these stressors, adoptive parents have been found to be able to successfully face the challenges related to the adoption process, showing many individuals, couples, and social resources (e.g., Ceballo et al., 2004; Levy-Shiff et al., 1990; Palacios & Sanchez-Sandoval, 2006; Rosnati et al., 2013). Overcoming tasks related to their role as adoptive parents may, indeed, have enhanced their coping abilities. Moreover, it is worthwhile noting that adoptive parents are required by law to undergo training by adoption agencies and to complete an extensive screening process. Thus, the impact of COVID-19 stressors on adoptive families may be amplified or reduced: on the one hand, the experiences they have gone through may place adoptive families at higher risk because they are alredy dealing with already dealing with additional stressful tasks related to their adoption status; on the other hand, those same experiences may have prepared them to be familiar with some of the negative consequences coming from stressful events and to use previously learned strategies for coping with COVID-related stressors as well. The data provided by the psychosocial literature before the pandemic regarding similarities and differences between adoptive and non-adoptive parents are not consistent. With regard to parenting stress, some studies found that adoptive parents report higher levels of stress than non-adoptive ones (e.g., McGlone et al., 2002; Paley et al., 2006; Rijk et al., 2006), whereas other studies reported lower levels of stress in adoptive parents compared to the normative population (Bird et al., 2002; Canzi et al., 2019a; Ceballo et al., 2004; Judge, 2003; Levy-Shiff et al., 1990; Palacios & Sanchez-Sandoval, 2006). Adoptive parents were also found to have a global more positive quality of couple relationship and dyadic functioning than non-adoptive parents (Canzi et al., 2019b; Ceballo et al., 2004; Lansford et al., 2001; Rosnati et al., 2013), also showing a stronger cohesion and interdependence between partners (Canzi et al., 2019b). Few studies have explored parent–child relationships, showing more similarities than differences between adoptive and non-adoptive parents. The two groups are characterized by similar levels of warm, cohesion, communication, support, and parental control (Lansford et al., 2001; Lanz et al., 1999; Paniagua et al., 2019; Rosnati et al., 2007; Rosnati & Marta, 1997; Rueter & Koerner, 2008; Wijedasa & Selwyn, 2011). The only exception is parent–child conflict in adolescence which was found by more than one study to be higher in adoptive families than in non-adoptive ones (Lansford et al., 2001; Lanz et al., 1999; Rueter et al., 2009). Finally, some studies showed adoptive families reporting higher satisfaction with the social support received from the community (e.g., Cohen et al., 1993; Fontenot, 2007; Levy-Shiff et al., 1990; Rosnati et al., 2013). Even if the literature on this topic is still sparse and limited, research suggested that adoptive parents can count on a broad social network and this could be considered an important resilience and protective factor in coping with the adoption process. Taking into account these circumstances, it seems to be relevant to compare adoptive and non-adoptive parents in terms of risks and resources in the face of the pandemic. Such a comparison could be useful to shed light on the specific features of adoptive families and, by consequence, to plan personalized and targeted interventions. According to the relational-symbolic model (Cigoli & Scabini, 2007), family's ability to cope with stressful situations may be influenced by the quality of family's resources which include (a) individual resources of each family member, (b) resources of the family system (couple and parent–child relationship), and (c) social and community resources. This multidimensional perspective can be effectively used to outline the various factors influencing parents’ adjustment process to a stressful event such as the pandemic. Purpose of the Present Study The current study was aimed at analyzing adoptive mothers’ COVID-19 risks (i.e., COVID-19-related stress) and individual (i.e., sense of coherence [SOC]), couple (i.e., partner's support), parent–child (i.e., parent–child relationship satisfaction), and social (i.e., friends’ support) resources in the face of the pandemic comparing them to non-adoptive mothers, and at predicting which variables discriminate more effectively between the two groups. We focused on mothers’ perceptions. As already mentioned in the introduction, mothers were found to be more challenged by the side effects of the pandemic, such as higher child-rearing responsibilities, often incompatible with work responsibilities (e.g., Petts et al., 2021). For what regards risks, we focused on two COVID-19-related stress dimensions, that are fear about the dangerousness of the virus and traumatic stress symptoms related to the virus (i.e., nightmares, intrusive thoughts, or images related to the virus). With regards to resources, we considered those variables that appeared to be protective factors in remaining healthy during the pandemic. Specifically, among individual resources, we considered the SOC that has emerged as a key factor in facing COVID-19-related stressors (Barni et al., 2020; Danioni et al., 2021; Mana et al., 2021; Schäfer et al., 2020). Individuals with high SOC, which is a global and enduring orientation to view the life and world as comprehensible, manageable, and meaningful, are more likely to perceive external stressors as predictable, under control, and worthy of engagement (Antonovsky, 1979), and therefore able to cope with stressors more effectively (e.g., Kaźmierczak et al., 2016). Among couple resources, we took into account perceived partner's support that has found to be one of the most important variables buffering negative consequences of stress and empowering coping strategies in facing challenging situation (Cohen & Wills, 1985; DeLongis et al., 2010; Donato et al., 2021; Rafaeli & Gleason, 2009). In this line, the study by McRae et al. (2021) has specifically documented that partner's support reduced the relation between parental distress during the COVID-19 lockdown and harsh parenting attitude. Among parent–child resources, we considered parents’ satisfaction about the relationship with their child: as several studies have shown parent–child relationship plays a significant role in buffering the effects of parental stress on children's psychological adjustment during the pandemic (e.g., Bate et al., 2021; Hussong et al., 2022; Janssens et al., 2021; Oliveira et al., 2021; Tang et al., 2021; Wang et al., 2021). Finally, we also focused on the protective role of social support against COVID-19-related challenges. Research on parents has largely documented, in both pre-pandemic (e.g., Benson, 2012; Parkes et al., 2015; Thoits, 2011; White & Hastings, 2004) and pandemic literature (e.g., Gambin et al., 2020; Oppermann et al., 2021; Ren et al., 2020), that social support is a key source of resilience, helping to face stressors and improving psychological well-being. Method Participants and Procedure Participants were 182 (40.9%) Italian adoptive mothers and 263 (59.1%) Italian non-adoptive mothers, for a total of 445 mothers, with a firstborn child aged between 6 and 22 years 1 . The demographic characteristics of participants are reported in Table 1. Most of the adoptions were international with a prevalence of children coming from Asia and the Russian Federation. Overall, adoptive mothers were more likely to be married or cohabiting, were higher educated (in line with Italian statistics: www.commissioneadozioni.it), and had less children compared to non-adoptive mothers. On the contrary, no statistically significant differences were found between the two groups in terms of mothers’ age, couple relationship duration, children's age (and consistently the stage of the family life cycle), and children's gender. Table 1. Demographics Characteristics of Adoptive and non-Adoptive Mothers. Adoptive Mothers (N = 182) Non-Adoptive Mothers (N = 263) M (SD) Range N % M (SD) Range N % t χ2 df Mothers’ age (years) 49.36 (5.46) 31–61 44.83 (6.29) 28–65 7.874*** 443 Marital status 4.922* 1 Cohabiting or married 182 100 256 97.3 Separated or divorced 0 0 7 2.7 Couple relationship duration (years) 18.52 (5.93) 6–36 17.38 (9.18) 0–61 1.592 441.087 Educational level (years) 16.62 (3.45) 8–21 14.90 (3.61) 8–21 5.001* 443 Number of children 2.45 (0.63) 2–5 2.73 (0.66) 2–5 −4.62* 443 Children's age 13.25 (4.40) 6–22 13.68 (4.69) 6–22 −.970 443 Stage of the family life cycle 5.055 3 Children between 6 and 11 66 36.3 96 36.5 Children between 12 and 15 63 34.6 69 26.2 Children between 16 and 18 23 12.6 48 18.3 Children between 19 and 22 30 16.5 50 19.0 Children's Gender 0.004 1 Male 103 56.6 148 56.3 Female 79 43.4 115 43.7 Type of adoption International adoption 121 66.5 Domestic adoption 49 26.9 Missing 12 6.6% Adopted children's age at placement (years) 4.87 (3.00) 1–12 Adopted children's birth country Europa 68 37.4 Africa 11 6.0 South America 52 28.6 Asia 18 9.9 Russian Federation 21 11.5 Missing 12 6.6 Note.**p < .001, p < .05. This study was part of a wider research titled [The Family at the Time of Covid-19”, carried out by the Family Studies and Research University Centre of the Università Cattolica del Sacro Cuore with the collaboration of Human Highway s.r.l..]. Parents gave informed consent before participation and were sent an online questionnaire asking to fill out guaranteeing their anonymity. The data collection phase took place between May 2021 and October 2021. The study was approved by the Ethics Committee of the [Department of Psychology of Università Cattolica del Sacro Cuore (protocol number 15–20)], and its procedures were followed by the American Psychological Association (http://www.apa.org/ethics/code/) and the Italian Association of Psychology (http://www.aipass.org/node/11560, accessed on April 10, 2022) ethical guidelines for human research. Measures The questionnaire included questions to collect sociodemographic information and the following measures. COVID-19 Stress Two subscales of the COVID-19 Stress Scale (CSS, Taylor et al., 2020) were used: fears about the dangerousness of COVID-19 (14 items) and traumatic stress symptoms related to COVID-19 (7 items). Mothers were asked to think about various kinds of worries about the virus or traumatic stress symptoms that they might have experienced over the past 7 days. The fear-related items were rated on a 5-point Likert scale from 0 (“not at all”) to 4 (“extremely”). An item example is: “I am worried that I can't keep my family safe from the virus”. The traumatic stress items were rated on a 5-point Likert scale ranging from 0 (“never”) to 4 (“almost always”). An item example is: “I had bad dreams about the virus.” The higher the scores, the higher the COVID-19-related fear and traumatic stress symptoms. Internal consistencies for the two subscales in the two groups are as follows: COVID-19 fear α = 0.89 (adoptive mothers) and α = 0.91 (non-adoptive mothers); COVID-19 traumatic stress symptoms α = 0.92 (adoptive mothers) and α = 0.94 (non-adoptive mothers). SOC Participants were asked to fill in the Italian version of the Sense of Coherence Scale (SOC, Barni & Tagliabue, 2005), which is composed of 11 items. Mothers reported on a 7-point Likert scale (from 1 = “very seldom or never” to 7 = “very often”) the extent to which they experienced the situation described during the pandemic. Item examples are: “I have feelings I’m in an unfamiliar situation and I don't know what to do” and “I have the feeling that I have being treated unfairly” (reversed items). The higher the total score, the higher the individual's SOC, which is the perception that his/her experiences in the world are comprehensible, manageable, and meaningful. Internal consistency of the total score in the two groups is as follows: α = 0.87 (adoptive mothers) and α = 0.91 (non-adoptive mothers). Parent–Child Relationship Satisfaction The satisfaction subscale of the Network of Relationships Inventory (NRI, Furman & Buhrmester, 1985; Italian translation by Guarnieri & Tani, 2011) was used to provide an index of the overall satisfaction for parent–child relationship. Mothers answered three items concerning the relationship with their child on a 5-point Likert scale (from 1 = “little or none” to 5 = “the most”). Mothers were asked to respond by thinking about their experience during the pandemic. An item example is “How happy are you with the way things are between you and your child?” The higher the total score, the higher the respondents’ satisfaction about parent–child relationship. Internal consistencies for the scale in the two groups are as follows: α = 0.92 (adoptive mothers) and α = 0.93 (non-adoptive mothers). Partner’s and Friends’ Support Participants responded to the partner's and friends’ subscales of the Multidimensional Scale of Perceived Social Support (MSPSS, Di Fabio & Palazzeschi, 2015; Zimet et al., 1988) assessing perceived support from the partner (four items) and from friends (four items) on a 5-point Likert scale (from 1 = “not at all” to 5 = “very much”). Mothers were asked to respond by thinking about their experience during the pandemic. An item example is “I can really talk to my partner/my friends of my problems”. The higher the score for each subscale on the average of the 4 items, the higher the respondents’ perception of support. Internal consistencies for the two subscales in the two groups are as follows: Partner α = 0.93 (adoptive mothers) and α = 0.94 (non-adoptive mothers), Friends α = 0.93 (adoptive mothers) and α = 0.93 (non-adoptive mothers). Data Analysis We first described the study's variables in terms of means, SDs, and ranges. According to our aim, we performed a multivariate analysis of variance (MANCOVA) to verify if there were significant differences between adoptive and non-adoptive mothers as far as COVID-19 stress and resources were concerned. For this purpose, we used the scores of COVID-19 fear, COVID-19 traumatic stress symptoms, SOC, partner's support, parent–child relationship satisfaction, and friends’ support as dependent variables and the status of mothers (1 = adoptive mothers and 2 = non-adoptive mothers) as the grouping variable. Correlations between the dependent variables reached moderate levels, and they were higher between the two subscales of the CSS (r = .56, p < .01) and between COVID-19 traumatic stress symptoms and SOC (r = −.50, p < .01). In addition, to control for children's age, we considered this variable as a covariate in the MANCOVA. According to our second aim, the MANCOVA was followed by a discriminant analysis (DA) in order to identify which variables under examination (i.e., risks and resources) best distinguished between the two groups (adoptive vs. non-adoptive mothers; Hair, 2005). DA is more and more frequently applied as a post hoc procedure in the context of multivariate studies by allowing to “think multivariately” (Huberty & Smith, 1982, p. 429) when conducting follow-up analyses of a statistically significant MANCOVA. With a more predictive aim, it can help in building a model to predict group membership. All statistical analyses were performed by SPSS 21.0 (IBM Corporation, Armonk, NY, USA). Results Table 2 reported means, SDs, and range for all study's variables separately for adoptive and non-adoptive mothers’ scores. The MANCOVA revealed significant group differences, Pillai's trace = 0.201, F(6,437) = 18.278, p < .001, η p 2 = 0.201. Univariate testing showed the effect to be significant for all the variables, regardless of children's age. Adoptive mothers reported higher levels of SOC, partner's support, and friends’ support, and lower levels of COVID-19 fear, COVID-19 traumatic stress symptoms, and parent–child relationship satisfaction compared to non-adoptive mothers (Table 2). Table 2. Means, SDs, and Range for the Study Variables and Differences (Univariate Testing) Between Adoptive and non-Adoptive Mothers. Adoptive Mothers (N = 182) Non-Adoptive Mothers (N = 263) M SD Range M SD Range F df ηp2 COVID-19 fear 3.08 0.92 1–5 3.51 0.94 1–5 22.66* 1 0.05 COVID-19 traumatic symptoms 1.73 0.87 1–5 2.53 1.09 1–5 68.02* 1 0.13 SOC 5.34 1.11 1–7 4.61 1.37 1–7 35.49*** 1 0.07 Partner's support 4.17 0.84 1–5 3.88 0.97 1–5 10.90* 1 0.02 P-C relationship satisfaction 3.59 0.88 1–5 3.83 0.89 1–5 9.70* 1 0.02 Friends’ support 3.73 0.98 1–5 3.42 0.98 1–5 11.02* 1 0.02 Notes. P-C = parent–child; SOC = sense of coherence. **p < .001, p < .05. The DA model had a Wilk's Lambda of 0.804, reaching a statically significant level [χ2(6) = 95.903, p < .001], accounting for 24% of variance, and with a canonical correlation of 0.443. The relative contribution of each variable is reported in Table 3. Variables are reported in their order of entry and the variables that contribute most to predicting group membership are those with the highest weights. The analysis showed that three dimensions contributed most to the discriminant function (coefficients > 0.30), namely COVID-19 traumatic stress symptoms, parent–child relationship satisfaction, and SOC. Scores for friends’ and partner's support were less relevant, and the contribution of COVID-19 fear was irrelevant. Of the total cases included in the model, based on the discriminant function, 70% of mothers were correctly classified as adoptive or non-adoptive, with a higher accuracy in predicting the status of adoptive mother (76.4%). Table 3. Discriminant Analysis (DA): Standardized Discriminant Function Coefficients. COVID-19 traumatic symptoms 0.636 P-C relationship satisfaction 0.511 SOC −0.337 Friends” support −0.262 Partner's support −0.172 COVID-19 fear 0.048 Note. Adoptive mothers = reference group. P-C = parent–child; SOC = sense of coherence. Discussion The current study was the first, to our knowledge, to focus on adoptive families in facing the prolonged COVID-19 pandemic and to explore if there were significant differences between adoptive and non-adoptive mothers, by jointly considering various domains of risks and resources (i.e., individual, couple, parent–child, and social resources). Our data showed a clear pattern of findings. Adoptive and non-adoptive mothers showed different risks and resilience resources in facing the stressors posed by the health emergency. As suggested by other studies (e.g., Tso et al., 2022) family structure may influence parents’ resilience in the face of stressful events, such as the current pandemic. Specifically, in line with the previous literature (e.g., Ceballo et al., 2004; Levy-Shiff et al., 1990; Rosnati et al., 2013), adoptive mothers were found to be better equipped than non-adoptive mothers in most of the considered dimensions. With regard to the risk factors, adoptive mothers showed lower levels of COVID-19-related stress both in terms of fear of the virus and traumatic stress symptoms related to the virus. The DA also showed that COVID-19-related traumatic stress symptoms, which accounted for the most variance, played an important role in discriminating between the two groups. Thus, the greatest difference between adoptive and non-adoptive mothers was more related to the exposure to risks than to their resources. This finding suggests that adoptive mothers showed a lower pathogenic reaction against the pandemic and for them, the challenges related to the pandemic may have taken on a less traumatic meaning compared to non-adoptive mothers. This supports the idea that adoptive mothers may be more familiar with some of the negative consequences coming from stressful and traumatic events, due to their previous experiences, and, as a consequence, less vulnerable. Indeed, couples who adopt a child often have overcome relationship stresses associated with infertility and have developed more coping responses during their life course. Besides, an appropriate adoptive parenting is the most critical “therapeutic mechanism” for the promotion of child recovery from previous difficulties (Ackerman & Dozier, 2005; Palacios et al., 2019). Adoptive parenthood requires therapeutic parenting competencies and adoptive parents are trained and prepared to increase their understanding of trauma, in order to support their children's recovery and the relationship with them. These circumstances can make adoptive mothers less exposed to the possible traumatic consequences of the pandemic. In this direction, our results also showed a significant difference in the level of SOC between the two groups and a high discriminating capacity of this variable, with adoptive mothers reporting greater ability to perceive external conditions (including stressors) as predictable, under control, and worthy of engagement, than non-adoptive mothers. Despite no studies compared the level of SOC in adoptive and non-adoptive parents, the literature has pointed out the significant impact of adoptive family's SOC on adoptees’ psychosocial adjustment (Ji et al., 2010), proving insight into the mechanisms involved in adoptive family's ability to cope with stress. According to the salutogenic approach (Antonovsky, 2022), our findings document a greater individual resilience capacity of adoptive mothers in coping with stressful situations: Adoptive mothers seem to be more able to manage stress related to the pandemic and less sensitive to this health challenge. Again, we can speculate that adoptive mothers have experienced many stressful life events and they not only “survived”, but they also empowered their coping abilities. Parent–child relationship dimension was also found to significantly contribute to discriminate between the two groups. Differently from previous literature showing more similarities than differences between adoptive and non-adoptive families (e.g., Lansford et al., 2001; Paniagua et al., 2019; Rosnati et al., 2007; Rueter et al., 2009), our findings showed that adoptive mothers reported lower satisfaction with their children than non-adoptive mothers. In discussing this finding, we must consider that parent–child interactions and relationships in adoptive families may be characterized by several daily difficulties related to the adoptive status and also to adopted children's greater vulnerability to emotional, behavioral, developmental, and learning problems (e.g., Askeland et al., 2018; Barroso et al., 2017). As suggested by van IJzendoorn and Juffer (2006), this may lead adoptive parents to be less satisfied with the relationship with their child compared to non-adoptive parents. In this direction, as adoptive children show a discrepancy between their cognitive competencies and school performance, due to the socio-emotional difficulties related to their adoption status (the well-known “adoption decalage” by van IJzendoorn et al., 2005), we can speculate that a similar mechanism occurs also in the family. Adoptive families may possess greater resilience resources, but since they face additional difficulties, they feel less satisfied and content about the relationship with their children. Nevertheless, it is plausible that adoptive mothers’ lower parent–child satisfaction reflects a realistic outlook about their children and a high sensitivity in detecting their difficulties. It is well known that adoptive parents are more prone to seek for help, as documented by the overrepresentation of adopted children in mental health services (Miller et al., 2000; Van IJzendoorn & Juffer, 2006). Finally, as far as the couple and social dimensions are concerned, our results showed a higher perceived support from partners and friends in adoptive mothers than non-adoptive ones. This is in line with the positive portrait of adoptive families emerging from several previous studies suggesting that they globally have higher level of quality of marital relationship, greater satisfaction for the support coming from the social context, and greater engagement in the community than non-adoptive families (e.g., Ceballo et al., 2004; Levy-Shiff et al., 1990; Rosnati et al., 2013). It is worthwhile noting the crucial role of the social dimension for adoptive families: Adoption is a form of “social generativity” that takes place in caring for a child born of other parents, with no genetic connection (e.g., Rosnati, 2015). However, these variables were found to contribute less in distinguishing adoptive mothers from the non-adoptive group. The study has some limitations that should be acknowledged when considering its findings. It relied on a convenience sample of Italian parents: While our groups were reasonably balanced in terms of sociodemographics, caution should be taken when generalizing the findings. Moreover, in the current study, only mothers’ perceptions were considered. In future studies, the inclusion of fathers’ perceptions would increase understanding of family experiences. Additionally, given the cross-sectional design of the research, we cannot understand if differences between adoptive and non-adoptive mothers were maintained over time or if they increased or decreased throughout the course of the pandemic. The use of self-report measures may have led to biased reporting and the use of an online platform may have attracted respondents with higher education levels with access to the Internet. Finally, future studies should be aimed at considering other variables that may contribute in distinguishing between adoptive and non-adoptive parents and in understanding their vulnerabilities and strengths in the face of stressful events. Implications and Applications This study can provide significant practical implications. Its findings suggest the importance to monitor both family's risks and resources in the face of the pandemic crisis. Specifically, the data were collected during the prolonged pandemic, shedding light on how parents are facing stressors that have being experienced over a long time. This is the first study to our knowledge to compare adoptive and non-adoptive parenthood in coping with COVID-19 effects, distinguishing the specific challenges adoptive and non-adoptive families face and the specific resources they can count on. Therefore, the present results may be useful to develop guidelines for clinicians on how to tailor mental health interventions to help parents coping with the circumstances posed by the pandemic, considering that family risks and resources may differ based on family structure. More specifically, our study documents the need for the adoption of competent mental health services in the direction to building a science of personalized interventions for adoptive parents by prioritizing or integrating multiple predictors of mental health. Our findings highlighted a weaker traumatic approach (in the sense of a pathogenic reaction) to the experiences related to the COVID-19 virus among adoptive mothers that showed unique resilient resources toward a salutogenic response to the extraordinary challenges posed by the pandemic. Nevertheless, adoptive mothers need to be targeted for intervention and to be supported to properly and in-depth use the resources they have in order to benefit and to increase the levels of parent–child satisfaction. Even in the face of COVID-19 stressors, it is possible to promote resilient behaviors and maintain a positive outlook (e.g., Gayatri & Irawaty, 2021). In this direction, we can argue that preventive and promotional interventions may be especially relevant to enhance family functioning and parent–child relationship quality (e.g., Watson et al., 2012). For example, the Family Enrichment Paths (Bertoni et al., 2017) is a recent form of family intervention suitable for this purpose. This intervention is developed based on the relational-symbolical model by Cigoli and Scabini (2007) and may be addressed to adoptive and non-adoptive parents. The general aims are to improve parents’ awareness of the resources present within the family, to favor participants’ reflection on their couple, parental, and social relationships, and to enrich parents’ competencies that will help them deal more effectively with the critical events that can determine family's vulnerability. Using these types of enrichment programs, relationships within the family, among the generations and also on a social community level, may be enhanced and strengthened. This study pushes to assume a preventive families’ intervention approach adopting a semi-structured format that is particularly suited to pay attention to the participants’ needs. In this way, it is possible for adoptive and non-adoptive parents to recognize the key aspect of parental identity, to acquire and enact better parenting competencies that allow to strengthen more satisfactory family relationships. The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article ORCID iD: Laura Ferrari https://orcid.org/0000-0003-2379-6227 1. The firstborn child is traditionally considered by the literature on family relationships to identify the stage of the family life cycle parents are facing (Cigoli & Scabini, 2007). ==== Refs References Ackerman J. Dozier M . (2005). The influence of foster parent investment on children’s representations of self and attachment figures. Applied Developmental Psychology, 26 (5 ), 507–520. 10.1016/j.appdev.2005.06.003 Adams E. L. Smith D. Caccavale L. J. Bean M. K . (2021). Parents are stressed! Patterns of parent stress across COVID-19. Frontiers in Psychiatry, 12 , 626456. 10.3389/fpsyt.2021.626456 33897489 Antonovsky A. (1979). Health, Stress and Coping. Jossey-Bass. Antonovsky A. (2022). Salutogenesis and the mental health of first responders. In The handbook of salutogenesis (pp. 543–551). Springer. Askeland K. G. Sivertsen B. Skogen J. C. La Greca A. M. Tell G. S. Aarø L. E. Hysing M . (2018). Alcohol and drug use among internationally adopted adolescents: Results from a Norwegian population-based study. American Journal of Orthopsychiatry, 88 (2 ), 226–235. 10.1037/ort0000231 28253017 Barni D. Danioni F. Canzi E. Ferrari L. Ranieri S. Lanz M. , …,& Rosnati R. (2020). Facing the COVID-19 pandemic: The role of sense of coherence. Frontiers in Psychology, 3027 . 10.3389/fpsyg.2020.578440 Barni D. Tagliabue S . (2005). Sense of coherence scale di antonovsky: Un contributo alla validazione italiana. Testing Psicometria Metodologia, 3 , 151–166. http://hdl.handle.net/10807/10345 Barroso R. Barbosa-Ducharne M. Coelho V. Costa I. S. Silva A . (2017). Psychological adjustment in intercountry and domestic adopted adolescents: A systematic review. Child and Adolescent Social Work Journal, 34 (5 ), 399–418. 10.1007/s10560-016-0485-x Bate J. Pham P. T. Borelli J. L . (2021). Be my safe haven: Parent-child relationships and emotional health during COVID-19. Journal of Pediatric Psychology, 46 (6 ), 624–634. 10.1093/jpepsy/jsab046 34283892 Behle A. E. Pinquart M . (2016). Psychiatric disorders and treatment in adoptees: A meta-analytic comparison with non-adoptees. Adoption Quarterly, 19 (4 ), 284–306. 10.1080/10926755.2016.1201708 Benson P. R . (2012). Network characteristics, perceived social support, and psychological adjustment in mothers of children with autism spectrum disorder. Journal of Autism and Developmental Disorders, 42 (12 ), 2597–2610. 10.1007/s10803-012-1517-9 22484793 Bertoni A. Donato S. Morgano A. Iafrate R. Rosnati R . (2017). A qualitative evaluation of a preventive intervention for parents: The groups for family enrichment_parent version (GFE_P). Journal of Prevention & Intervention in the Community, 45 (3 ), 215–229. 10.1080/10852352.2016.1198135 28641064 Bird G. Peterson R. Miller S. H . (2002). Factors associated with distress among support-seeking adoptive parents. Family Relations, 51 (3 ), 215–220. 10.1111/j.1741-3729.2002.00215.x Brooks S. K. Webster R. K. Smith L. E. Woodland L. Wessely S. Greenberg N. Rubin G. J . (2020). The psychological impact of quarantine and how to reduce it: Rapid review of the evidence. The Lancet, 395 (10227 ), 912–920. 10.1016/S0140-6736(20)30460-8 Brown S. M. Doom J. R. Lechuga-Peña S. Watamura S. E. Koppels T . (2020). Stress and parenting during the global COVID-19 pandemic. Child Abuse & Neglect, 110 (2 ), 104699. 10.1016/j.chiabu.2020.104699 32859394 Calarco J. Anderson E. Meanwell E. Knopf A . (2020). “Let’s not pretend it’s fun”: How COVID-19-related school and childcare closures are damaging to mothers’ well-being. SocArXiv . 10.31235/osf.io/jyvk4 Canzi E. Ranieri S. Barni D. Rosnati R . (2019a). Predictors of parenting stress during early adoptive parenthood. Current Psychology, 38 (3 ), 811–820. 10.1007/s12144-017-9657-x Canzi E. Donato S. Ferrari L. Parise M. Pagani A. F. Lopez G. Rosnati R. Ranieri S . (2019b). “What makes us strong?”: Dyadic coping in Italian prospective adoptive couples. Frontiers in Psychology, 10 , 399. 10.3389/fpsyg.2019.00399 30894825 Ceballo R. Lansford J. Abbey A. Stewart A . (2004). Gaining a child: Comparing the experiences of biological parents, adoptive parents and stepparents. Family Relations, 53 (1 ), 38–48. 10.1111/j.1741-3729.2004.00007.x Cigoli V. Scabini E. (2007). Family identity: Ties, symbols, and transitions. Routledge. Choi M. Tessler H. Kao G . (2020). Arts and crafts as an educational strategy and coping mechanism for Republic of Korea and United States parents during the COVID-19 pandemic. International Review of Education, 66 (5 ), 715–735. 10.1007/s11159-020-09865-8 33110275 Cohen N. J. Coyne J. Duvall J . (1993). Adopted and biological children in the clinic: Family, parental and child characteristics. Journal of Child Psychology and Psychiatry, 34 (4 ), 545–562. 10.1111/j.1469-7610.1993.tb01035.x 8509494 Cohen S. Wills T. A . (1985). Stress, social support, and the buffering hypothesis. Psychological Bulletin, 98 (2 ), 310–357. https://psycnet.apa.org/doi/10.1037/0033-2909.98.2.310 3901065 Daniluk J. C. Hurtig-Mitchell J. (2003). Themes of hope and healing: Infertile couples’ experiences of adoption. Journal of Counseling & Development, 81 (4 ), 389–399. 10.1002/j.1556-6678.2003.tb00265.x Danioni F. Sorgente A. Barni D. Canzi E. Ferrari L. Ranieri S. Iafrate R. Regalia C. Rosnati R. Lanz M . (2021). Sense of coherence and COVID-19: A longitudinal study. Journal of Psychology, 155 (7 ), 657–677. 10.1080/00223980.2021.1952151 34289329 DeLongis A. Holtzman S. Outerman E. Lam M. (2010). Dyadic coping: Support from the spouse in times of stress. In Davila J. Sullivan K. (Eds.), Social support processes in intimate relationships (pp. 151–174). Oxford Press. 10.1093/acprof:oso/9780195380170.003.0006 Di Fabio A. Palazzeschi L . (2015). Multidimensional Scale of Perceived Social Support (MSPSS): Un contributo alla validazione italiana. Counseling: Giornale Italiano di Ricerca e Applicazioni, 8 (2 ), 127–140. Donato S. Parise M. Pagani A. F. Lanz M. Regalia C. Rosnati R. Iafrate R . (2021). Together against COVID-19 concerns: The role of the dyadic coping process for partners’ psychological well-being during the pandemic. Frontiers in Psychology, 11 , 3681. 10.3389/fpsyg.2020.578395 Fontenot H. B . (2007). Transition and adaptation to adoptive motherhood. Journal of Obstetric, Gynecologic, & Neonatal Nursing, 36 (2 ), 175–182. 10.1111/j.1552-6909.2007.00134.x Furman W. Buhrmester D . (1985). Children’s perceptions of the personal relationships in their social networks. Developmental Psychology, 21 (6 ), 1016–1024. 10.1037/0012-1649.21.6.1016 Gambin M. Woźniak-Prus M. Sekowski M. Cudo A. Pisula E. Kiepura E. Kmita G . (2020). Factors related to positive experiences in parent-child relationship during the COVID-19 lockdown: The role of empathy, emotion regulation, parenting self-efficacy and social support. PsyArXiv. 10.31234/osf.io/yhtqa Gayatri M. Irawaty D. K . (2021). Family Resilience during COVID-19 pandemic: A literature review. The Family Journal, 30 (2 ), 132–138. 10.1177/10664807211023875 Goldberg A. E. McCormick N. Virginia H . (2021). Parenting in a pandemic: Work–family arrangements, well-being, and intimate relationships among adoptive parents. Family Relations, 70 (1 ), 7–25. 10.1111/fare.12528 Guarnieri S. Tani F . (2011). Social networks and life satisfaction in emerging adulthood. Journal of Developmental Psychology, 99 , 34–52. Hair H. J . (2005). Outcomes for children and adolescents after residential treatment: A review of research from 1993 to 2003. Journal of Child and Family Studies, 14 (4 ), 551–575. 10.1007/s10826-005-7188-9 Herbert J. S. Mitchell A. Brentnall S. J. Bird A. L . (2020). Identifying rewards over difficulties buffers the impact of time in COVID-19 lockdown for parents in Australia. Frontiers in Psychology, 11 , 3441. 10.3389/fpsyg.2020.606507 Hussong A. Midgette A. Richards A. Petrie R. Coffman J. Thomas T . (2022). COVID-19 life events spill-over on family functioning and adolescent adjustment. The Journal of Early Adolescence, 42 (3 ), 359–388. 10.1177/02724316211036744 35177875 Janssens J. J. Achterhof R. Lafit G. Bamps E. Hagemann N. Hiekkaranta A. P. , …, & Kirtley O. J. (2021). The impact of COVID-19 on adolescents daily lives: The role of parent-child relationship quality. Journal of Research on Adolescence, 31 (3 ), 623–644. 10.1111/jora.12657 34448305 Ji J. Brooks D. Barth R. P. Kim H . (2010). Beyond preadoptive risk: The impact of adoptive family environment on adopted youth’s psychosocial adjustment. American Journal of Orthopsychiatry, 80 (3 ), 432–442. 10.1111/j.1939-0025.2010.01046.x 20636948 Judge S . (2003). Determinants of parental stress in families adopting children from Eastern Europe. Family Relations, 52 (3 ), 241–248. 10.1111/j.1741-3729.2003.00241.x Kaźmierczak I. Strelau J. Zawadzki B . (2016). Post-traumatic cognitions as a mediator of the relationship between sense of coherence and post-traumatic stress disorder after motor vehicle accidents. Transportation Research Part F: Traffic Psychology and Behaviour, 41 (A ), 38–44. 10.1016/j.trf.2016.06.014 Lansford J. E. Ceballo R. Abbey A. Stewart A. J . (2001). Does family structure matter? A comparison of adoptive, two-parent biological, single mother, stepfather, and stepmother households. Journal of Marriage and Family, 63 (3 ), 840–851. 10.1111/j.1741-3737.2001.00840.x Lanz M. Iafrate R. Rosnati R. Scabini E . (1999). Parent–child communication and adolescent self-esteem in separated, intercountry adoptive and intact non-adoptive families. Journal of Adolescence, 22 (6 ), 785–794. 10.1006/jado.1999.0272 10579890 Lei L. Huang X. Zhang S. Yang J. Yang L. Xu M . (2020). Comparison of prevalence and associated factors of anxiety and depression among people affected by versus people unaffected by quarantine during the COVID-19 epidemic in southwestern China. Medical Science Monitor: International Medical Journal of Experimental and Clinical Research, 26 , e924609–1. 10.12659/msm.924609 32335579 Levy-Shiff R. Bar O. Har-Even D . (1990). Psychological adjustment of adoptive parents-to-be. American Journal of Orthopsychiatry, 60 (2 ), 258–267. 10.1037/h0079165 2343893 Liu X. Kakade M. Fuller C. J. Fan B. Fang Y. Kong J. Guan Z. Wu P . (2012). Depression after exposure to stressful events: Lessons learned from the severe acute respiratory syndrome epidemic. Comprehensive Psychiatry, 53 (1 ), 15–23. 10.1016/j.comppsych.2011.02.003 21489421 Mana A. Bauer G. F. Magistretti C. M. Sardu C. Juvinyà-Canal D. Hardy L. J. , …, & Sagy S. (2021). Order out of chaos: Sense of coherence and the mediating role of coping resources in explaining mental health during COVID-19 in 7 countries. SSM-Mental Health, 1 , 100001. 10.1016/j.ssmmh.2021.100001 34604824 McGlone K. Santos L. Kazama L. Fong R. Mueller C . (2002). Psychological stress in adoptive parents of special-needs children. Child Welfare, 81 (2 ), 151–171. http://www.jstor.org/stable/45390055 12014464 McRae C. S. Overall N. C. Henderson A. M. Low R. S. Chang V. T . (2021). Parents’ distress and poor parenting during a COVID-19 lockdown: The buffering effects of partner support and cooperative coparenting. Developmental Psychology, 57 (10 ), 1623–1632. 10.1037/dev0001207 34807685 Miller B. C. Fan X. Grotevant H. D. Christensen M. Coyl D. Van Dulmen M . (2000). Adopted adolescents’ overrepresentation in mental health counseling: Adoptees’ problems or parents’ lower threshold for referral? Journal of the American Academy of Child & Adolescent Psychiatry, 39 (12 ), 1504–1511. 10.1097/00004583-200012000-00011 11128327 Nickell L. A. Crighton E. J. Tracy C. S. Al-Enazy H. Bolaji Y. Hanjrah S. , …, & Upshur R. E. (2004). Psychosocial effects of SARS on hospital staff: Survey of a large tertiary care institution. Canadian Medical Association Journal, 170 (5 ), 793–798. 10.1503/cmaj.1031077 14993174 Oliveira T. D. O. Costa D. S. Alvim-Soares A. de Paula J. J. Kestelman I. Silva A. G. , …, & Miranda D. M. (2021). Children’s behavioral problems, screen time, and sleep problems’association with negative and positive parenting strategies during the COVID-19 outbreak in Brazil. Child Abuse & Neglect, 130 (1 ), 105345. 10.1016/j.chiabu.2021.105345 34625278 Oppermann E. Cohen F. Wolf K. Burghardt L. Anders Y . (2021). Changes in parents’ home learning activities with their children during the COVID-19 lockdown–the role of parental stress, parents’ self-efficacy and social support. Frontiers in Psychology, 12 , 682540. 10.3389/fpsyg.2021.682540 34393909 Palacios J. Rolock N. Selwyn J. Barbosa-Ducharne M . (2019). Adoption breakdown: Concept, research, and implications. Research on Social Work Practice, 29 (2 ), 130–142. 10.1177/1049731518783852 Palacios J. Sánchez-Sandoval Y . (2006). Stress in parents of adopted children. International Journal of Behavioral Development, 30 (6 ), 481–487. 10.1177/0165025406071492 Paley B. O’connor M. J. Frankel F. Marquardt R . (2006). Predictors of stress in parents of children with fetal alcohol spectrum disorders. Journal of Developmental & Behavioral Pediatrics, 27 (5 ), 396–404. 10.1097/00004703-200610000-00005 17041276 Paniagua C. Moreno C. Rivera F. Jiménez-Iglesias A. (2019) Adolescents’ perceptions of family relationships in adoptees and non-adoptees: More similarities than differences. The British Journal of Social Work, 49 (1 ), 25–43. 10.1093/bjsw/bcy028 Parkes A. Sweeting H. Wight D . (2015). Parenting stress and parent support among mothers with high and low education. Journal of Family Psychology, 29 (6 ), 907–918. 10.1037/fam0000129 26192130 Petts R. J. Carlson D. L. Pepin J. R . (2021). A gendered pandemic: Childcare, homeschooling, and parents’ employment during COVID-19. Gender, Work & Organization, 28 (S2 ), 515–534. 10.1111/gwao.12614 Rafaeli E. Gleason M. E . (2009). Skilled support within intimate relationships. Journal of Family Theory & Review, 1 (1 ), 20–37. 10.1111/j.1756-2589.2009.00003.x Ren J. Li X. Chen S. Chen S. Nie Y . (2020). The influence of factors such as parenting stress and social support on the state anxiety in parents of special needs children during the COVID-19 epidemic. Frontiers in Psychology, 11 , 3413. 10.3389/fpsyg.2020.565393 Rijk C. H. Hoksbergen R. A. ter Laak J. J. van Dijkum C. Robbroeckx L. H. M. (2006). Parents who adopt deprived children have a difficult task. Adoption Quarterly, 9 (2–3 ), 37–61. 10.1300/J145v09n02_03 Rosnati R . (2015). Family resources in the transition to adoption: Introduction to the special section. Family Science, 6 (1 ), 38–42. 10.1080/19424620.2015.1080962 Rosnati R. Iafrate R. Scabini E . (2007). Parent-adolescent communication in foster, inter-country adoptive, and biological Italian families: Gender and generational differences. International Journal of Psychology, 42 (1 ), 36–45. 10.1080/00207590500412128 24274778 Rosnati R. Marta E . (1997). Parent–child relationships as a protective factor in preventing adolescents’ psychosocial risk in inter-racial adoptive and non-adoptive families. Journal of Adolescence, 20 (6 ), 617–631. 10.1006/jado.1997.0115 9417795 Rosnati R. Ranieri S. Barni D . (2013). Family and social relationships and psychosocial well-being in Italian families with internationally adopted and non-adopted children. Adoption Quarterly, 16 (1 ), 1–16. 10.1080/10926755.2012.731030 Rueter M. A. Keyes M. A. Iacono W. G. McGue M . (2009). Family interactions in adoptive compared to nonadoptive families. Journal of Family Psychology, 23 (1 ), 58–66. https://psycnet.apa.org/doi/10.1037/a0014091 19203160 Rueter M. A. Koerner A. F . (2008). The effect of family communication patterns on adopted adolescent adjustment. Journal of Marriage and Family, 70 (3 ), 715–727. 10.1111/j.1741-3737.2008.00516.x 19649145 Schäfer S. K. Sopp M. R. Schanz C. G. Staginnus M. Göritz A. S. Michael T . (2020). Impact of COVID-19 on public mental health and the buffering effect of a sense of coherence. Psychotherapy and Psychosomatics, 89 (6 ), 386–392. 10.1159/000510752 32810855 Spinelli M. Lionetti F. Pastore M. Fasolo M . (2020). Parents’ stress and children’s psychological problems in families facing the COVID-19 outbreak in Italy. Frontiers in Psychology, 11 , 1713. 10.3389/fpsyg.2020.01713 32719646 Tang S. Xiang M. Cheung T. Xiang Y. T . (2021). Mental health and its correlates among children and adolescents during COVID-19 school closure: The importance of parent-child discussion. Journal of Affective Disorders, 279 , 353–360. 10.1016/j.jad.2020.10.016 33099049 Taylor M. R. Agho K. E. Stevens G. J. Raphael B . (2008). Factors influencing psychological distress during a disease epidemic: Data from Australia’s first outbreak of equine influenza. BMC Public Health, 8 (1 ), 1–13. 10.1186/1471-2458-8-347 18173844 Taylor S. Landry C. A. Paluszek M. M. Fergus T. A. McKay D. Asmundson G. J . (2020). COVID Stress syndrome: Concept, structure, and correlates. Depression and Anxiety, 37 (8 ), 706–714. 10.1002/da.23071 32627255 Thoits P. A . (2011). Mechanisms linking social ties and support to physical and mental health. Journal of Health and Social Behavior, 52 (2 ), 145–161. 10.1177/0022146510395592 21673143 Tso W. W. Wong R. S. Tung K. T. Rao N. Fu K. W. Yam J. Chua G. T. Chen E. Lee T. Chan S. Wong W. Xiong X. Chui C. Li X. Wong K. Leung C. Tsang S. Chan G. Tam P. Chan K. Kwan M. Ho M. Chow C. Wong I. Lp P. (2022). Vulnerability and resilience in children during the COVID-19 pandemic. European Child & Adolescent Psychiatry, 31 (1 ), 161–176. 10.1007/s00787-020-01680-8 33205284 Twenge J. M. Joiner T. E . (2020). Mental distress among US adults during the COVID-19 pandemic. Journal of Clinical Psychology, 76 (12 ), 2170–2182. 10.1002/jclp.23064 33037608 Van IJzendoorn M. H. Juffer F . (2006). The Emanuel Miller memorial lecture 2006: Adoption as intervention. Meta-analytic evidence for massive catch-up and plasticity in physical, socio-emotional, and cognitive development. Journal of Child Psychology and Psychiatry, 47 (12 ), 1228–1245. 10.1111/j.1469-7610.2006.01675.x 17176378 Van Ijzendoorn M. H. Juffer F. Poelhuis C. W. K . (2005). Adoption and cognitive development: A meta-analytic comparison of adopted and nonadopted children’s IQ and school performance. Psychological Bulletin, 131 (2 ), 301–316. 10.1037/0033-2909.131.2.301 15740423 Wang J. Wang H. Lin H. Richards M. Yang S. Liang H. , …, & Fu C. (2021). Study problems and depressive symptoms in adolescents during the COVID-19 outbreak: Poor parent-child relationship as a vulnerability. Globalization and Health, 17 , 40. 10.1186/s12992-021-00693-5 33823875 Watson M. T. Stern N. M. Foster T. W . (2012). Helping parents and adoptees through the adoption process using group work. The Family Journal, 20 (4 ), 433–440. 10.1177/1066480712451254 Weaver J. L. Swank J. M . (2021). Parents’ lived experiences with the COVID-19 pandemic. The Family Journal, 29 (2 ), 136–142. 10.1177/1066480720969194 White N. Hastings R. P . (2004). Social and professional support for parents of adolescents with severe intellectual disabilities. Journal of Applied Research in Intellectual Disabilities, 17 (3 ), 181–190. 10.1111/j.1468-3148.2004.00197.x Wijedasa D. Selwyn J. (2011). Transition to adulthood for young people in adoptive care. School for Policy Studies. Zhang S. X. Liu J. Jahanshahi A. A. Nawaser K. Yousefi A. Li J. Sun S . (2020). At the height of the storm: Healthcare staff’s health conditions and job satisfaction and their associated predictors during the epidemic peak of COVID-19. Brain, Behavior, and Immunity, 87 , 144–146. 10.1016/j.bbi.2020.05.010 32387345 Zimet G. D. Dahlem N. W. Zimet S. G. Farley G. K . (1988). The multidimensional scale of perceived social support. Journal of Personality Assessment, 52 (1 ), 30–41. 10.1207/s15327752jpa5201_2
PMC009xxxxxx/PMC9483861.txt	==== Front Small Bus Econ Small Business Economics 0921-898X 1573-0913 Springer US New York 687 10.1007/s11187-022-00687-6 Article Drivers of fragility in the ventures of poverty entrepreneurs http://orcid.org/0000-0003-2784-410X Morris Michael H. [email protected] 1 Soleimanof Sohrab 2 Tucker Reginald 2 1 grid.131063.6 0000 0001 2168 0066 Keough School of Global Affairs, University of Notre Dame, Notre Dame, IN 46556 USA 2 grid.64337.35 0000 0001 0662 7451 Stephenson Department of Entrepreneurship & Information Systems, E. J. Ourso College of Business Administration, Louisiana State University, Baton Rouge, LA 70803 USA 19 9 2022 2023 61 1 305323 2 9 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. This study examines whether and how the experience of poverty shapes the entrepreneurial journey. The research builds upon disadvantage theory to explore how liabilities resulting from the poverty experience can serve as obstacles to the creation of sustainable enterprises. An analysis of data from a sample of 202 entrepreneurs in poverty contexts in the USA demonstrates how liability of poorness (LOP) factors leads to the emergence of more fragile ventures. The findings further indicate that entrepreneurial alertness can moderate the effect of LOP on venture fragility. The study offers theoretical and practical suggestions for further understanding and fostering entrepreneurship as a viable solution to poverty. How poverty conditions affect a person’s ability to start a successful business. Creating a successful business can be difficult for anyone, but especially for those who come from poverty circumstances. This study demonstrates how ventures created by poverty entrepreneurs tend to be more fragile or subject to serious decline or failure when the inevitable threat or unexpected setback occurs. Two key aspects of poverty, experienced scarcity and significant nonbusiness distractions, combine to lead entrepreneurs to create more fragile businesses. However, when a low-income individual demonstrates more entrepreneurial alertness, a variable associated with venture success, the negative effect of poverty-related variables is reduced. The findings suggest that, for entrepreneurship to be a viable pathway out of poverty, public policies and community-based programs should focus on reducing the fragility of these ventures and enhancing the opportunity recognition skills of these entrepreneurs. Keywords Liability of poorness Venture fragility Entrepreneurial alertness Poverty alleviation JEL classifications L25 L26 issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcTo what extent does entrepreneurship represent a solution to poverty? Recent studies suggest the poor start large numbers of businesses and many are able to improve their economic standing through venture creation (Amorós et al., 2021; Naminse & Zhuang, 2018; Slivinski, 2012). At the same time, a number of observers question the value of such ventures. They argue businesses started by the poor are generally inefficient, fail at high rates, generate few jobs and little intellectual property, and do not contribute to economic productivity (Acs & Kallas, 2008; Acs & Szerb, 2007; Shane, 2009). Morris et al. (2018) explained that those in poverty disproportionately create necessity-driven ventures that suffer from the “commodity trap,” referring to ventures that are undifferentiated and labor-intensive and have low profit margins, high unit costs, no bargaining power, and limited production capacity. As a result, they can be highly fragile businesses, especially vulnerable to shocks and setbacks such as the COVID-19 pandemic (Odeku, 2020). Such divergent views persist despite the growing volume of scholarship addressing the poverty and entrepreneurship interface (Alvarez & Barney, 2014; Banerjee & Duflo, 2011; Bruton et al., 2013; Castellanza, 2020; Webb et al., 2013). Researchers have produced insufficient empirical evidence to address some of the most formative questions at the interface, such as the rate of start-up activity by those in poverty, failure rates and average life of these ventures, factors contributing to their success, and extent to which these ventures move people out of poverty. Poverty is a multidimensional phenomenon transcending a lack of money (Morland et al., 2002; Wilson, 1996). As such, Morris et al. (2022) concluded that low-income individuals face unique challenges when launching a venture, which they label the “liability of poorness.” The question becomes one of determining how poverty conditions influence the viability of these ventures. The current research seeks to explore this question. We draw upon disadvantage theory (Light, 1979) to explain how the liability of poorness (LOP) increases the fragility of the businesses being created. Fragility, in this context, refers to “the venture’s vulnerability to inherent obstacles and unexpected shocks and its limited capacity to cope with adverse conditions” (Morris, 2020, p. 304). We approach the LOP in terms of two widely noted challenges faced by low-income individuals: experienced scarcity, or the effects of prolonged exposure to insufficient resources to address basic needs (Mullainathan & Shafir, 2013), and an inability to maintain focus, which results from significant nonbusiness distractions (Dermott & Pomati, 2016; Morris et al., 2022). At the same time, individuals in poverty contexts are not inherently destined to create fragile ventures. Numerous examples exist of entrepreneurs who overcame the disadvantages imposed by poverty to build successful businesses (Bandiera et al., 2013; John & Poisner, 2016). In this regard, researchers have placed significant emphasis on the importance of entrepreneurial alertness, or the ability to detect signals from the environment and recognize business opportunities, as a factor contributing to successful venture creation (Kirzner, 1999). Accordingly, we posit that individuals in poverty contexts can develop cognitive and behavioral capabilities required for expanding the range of opportunities available to them (Alvarez & Barney, 2014), which can enable those individuals to build more viable businesses. Hence, we propose that entrepreneurial alertness can moderate the effect of the LOP on venture fragility. We develop a research model and set of hypotheses regarding these relationships. To test the hypotheses, a survey was administered to a sample of entrepreneurs from poverty and disadvantaged backgrounds in urban areas within the USA. The results support our hypotheses that poverty conditions can result in higher levels of venture fragility and that entrepreneurial alertness can alleviate the negative effects of the LOP on fragility. Hence, entrepreneurial alertness may be considered as a capability that enables poverty entrepreneurs to leverage entrepreneurship as a pathway out of poverty. Implications are drawn for theory, practice, and policy. The research offers several contributions. First, the study sheds light on the entrepreneurial journeys of those in poverty and places overcoming fragility at the center of discussions of the efficacy of entrepreneurship as a poverty solution. Fragility has heretofore largely been examined in the context of large, established firms (e.g., Cómbita Mora, 2020; Cueva et al., 2017; Den Haan et al., 2003), with only limited examination of its role in early-stage ventures (Bartik, et al., 2020; Bottazzi, Secchi & Tamagni, 2006; Madi, 2013). Beyond understanding why, how, and the extent to which those experiencing poverty start ventures, a focus on fragility highlights the importance of examining the sustainability of these ventures. Second, our findings contribute to disadvantage theory (Boyd, 2000; Light, 1979) by showing how disadvantages associated with poverty can simultaneously direct individuals towards entrepreneurship while also leading them into potentially problematic ventures that cannot provide a pathway out of poverty. While these contrasting effects are suggested by the duality of disadvantage theory, extant research has emphasized the tendency of the disadvantaged to create informal sector and survival ventures (Boyd, 2000; Herring, 2004; Webb et al., 2013) without considering the sustainability of these ventures. Furthermore, we shed light on how understanding the nature of such disadvantages can provide direction for generating more sustainable ventures. Third, the study adds to the entrepreneurial alertness literature (Amato et al., 2017; Gaglio & Katz, 2001). Alertness has been associated with the number and quality of opportunities identified by entrepreneurs, their tendency to launch ventures, as well as the innovativeness and performance of these ventures (van Gelderin, 2008; Shane et al., 1991; Tang, 2012). This is the first work to highlight its critical role in overcoming disadvantages that derive from the poverty experience. Given that alertness can be taught and improved, the results suggest individuals affected by scarcity can develop capabilities that empower them to create sustainable ventures. These findings have important implications for entrepreneurship policy and education. Research background While a number of scholars have theorized about issues at the poverty and entrepreneurship interface (e.g., Bruton et al., 2015; Nakara et al., 2021; Neumeyer et al., 2021), most have not positioned their approach within an established theoretical framework. An exception is Santos et al. (2019), who used empowerment theory to explain how entrepreneurship can foster motivation to overcome a sense of powerlessness, a lack of resources, and limited autonomy and ultimately can help individuals gain control over their lives. Similarly, Shepherd et al. (2021) have used the status-attainment theory to understand how entrepreneurs living in Indian slums could derive a sense of worth from entrepreneurship and how their poverty experience compelled greater education for their children. Thus, prior studies have highlighted the importance of poverty entrepreneurship while also recognizing that poverty circumstances put the poor at a disadvantage in the entrepreneurial context (Bruton et al., 2021). As such, a theory of disadvantage is valuable for understanding the poverty and entrepreneurship interface. Disadvantage theory from sociology (Boyd, 2000; Light, 1979) holds some promise in this regard, particularly in its focus on disadvantage resulting from poverty, economic exclusion, and discrimination. The theory emphasizes the duality of disadvantage when it comes to behavior, where disadvantage serves as motivator and inhibitor. On the one hand, disadvantage can provide a motivation for an individual to pursue entrepreneurship as he or she is less competitive for attractive job opportunities in the mainstream economy. This has been referred to as labor market disadvantage, and it leads individuals to strike out on their own. While the term injunctification has been used to capture a tendency to accept the status quo when in disadvantaged circumstances (Kay et al., 2009), researchers have noted a motivation tied to disadvantage that enables the person to transcend their circumstances, escape the status quo, and realize the fruits of their labors (Krishna, 2004; Williams et al., 2017). Individuals are unwilling to become victims of their circumstances, and, in some instances, their motives are altruistic, wanting something better for their families and the next generation (Rockinson-Szapkiw et al., 2016). Hence, disadvantage can induce a drive for success (John & Poisner 2016; Morris & Tucker, 2021). When it comes to entrepreneurship, disadvantage as motivator suggests that the downsides of poverty can serve to enhance the relative attractiveness of venture creation, particularly where disadvantage results in less attractive options such as unemployment, significant underemployment, or jobs with subpar wages (Morris et al., 2022). Furthermore, a person in disadvantaged circumstances has a greater tendency to pursue risk-assumptive behavior, such as venture creation, particularly when perceiving they have little to lose (Sadler, 2000; Walton, 2018). In addition, as the individual makes progress in pursuing a venture, they are motivated to persevere in building on those results to ultimately find a pathway out of their disadvantaged circumstances (Krishna, 2004). At the same time, there is some evidence that, when the disadvantaged start ventures, the venture can become an end in itself, where the entrepreneur is motivated by the desire to be his/her own boss, and profit-making is less of a consideration (Wong, 1977; Silverman, 1999). On the other hand, disadvantage can serve as an inhibitor when it produces constraints or barriers, particularly where it limits the ability and/or willingness of the individual to act. At least four disadvantage-related constraints have been identified: inadequate resources, insufficient capabilities, limits on access to a given opportunity, and diminished self-perceptions of one’s potential and place in society. Poverty conditions often produce all four of these constraints (Morris, et al., 2022; Payne et al., 2006; Wilson, 2012). Furthermore, when the person in poverty is part of a minority or ethnic group, entrepreneurship researchers have found evidence of opportunity-limiting discrimination from a range of different stakeholders (Jackson et al., 2018; Kuppuswamy & Younkin, 2020; Younkin & Kuppuswamy, 2019). Such constraints can deter the poverty entrepreneur from launching businesses altogether, but, when a venture is pursued, can influence what actually gets created. Constraints can result in a greater tendency to launch survival ventures (Boyd, 2000) and businesses in the informal sector (Herring, 2004; Webb et al., 2013). They can result in entrepreneurs taking what Butler (1991) refers to as an “economic detour,” where they limit the potential of the business by focusing only on their immediate networks and people with similar backgrounds to their own, and fail to penetrate mainstream markets. They believe capital constraints and discrimination close opportunities to them in the broader economy (Silverman, 1999). Disadvantage theory has been used to explain the entrepreneurial activity of women, immigrants, and minorities (Boyd, 2000; Cooper & Dunkelberg, 1987; Horton & DeJong, 1991; Light & Rosenstein, 1995). Light (1979) relied on this theory to explain increased entrepreneurial activity resulting from overurbanization as rural residents in developing countries move to cities and cannot find work. In sum, disadvantaged circumstances can push the individual toward entrepreneurship while posing major challenges when developing their ventures. This duality may have important implications for the sustainability of the ventures created by the poor, a topic that has received little attention. The constraints imposed by a poverty background may lead the entrepreneur to approach the business in ways that produce more fragile and underperforming ventures. To appreciate this possibility, we need to first explore the disadvantages created by poverty when launching a venture and then clarify the concept of venture fragility. Disadvantage, poverty, and entrepreneurship Poverty is a key indicator of social exclusion and an underlying characteristic of many of the groups examined in disadvantage studies (e.g., Boyd, 2000; Butler, 1991; Herring, 2004). The disadvantages associated with poverty go well beyond severe financial constraints (Wilson, 1996). Other aspects of the experience that contribute to disadvantage include substandard literacy levels and school drop-out rates well above the norm (Hernandez, 2011), lack of employment opportunities and underemployment in labor-intensive and often part-time jobs with no benefits (Morris et al., 2018), inadequate housing conditions and undernutrition (Morland, et al., 2002), food insecurity (Piaseu & Mitchell, 2004), chronic medical conditions and early child mortality (Von Braun et al., 2009), teenage child-bearing and single parenthood (Maldonado & Nieuwenhuis, 2015), lack of dependable transportation (Chetty & Hendren, 2018), constant fatigue (Tirado, 2015), physical insecurity (Chronic Poverty Research Centre 2009), segregation from much of society (Wilson, 1996), and limited social networks (Weyers et al., 2008). Morris (2020) has attempted to draw implications from the multidimensional nature of poverty for entrepreneurial activity. All entrepreneurs confront numerous obstacles as reflected in the liabilities of newness and smallness (Hannan & Freeman, 1984; Stinchcombe, 1965). However, the poverty experience can introduce an additional set of obstacles, which has been termed the liabilities of poorness. It refers to “the potential for failure of a new venture due to difficulties encountered that are traceable to the characteristics and influences deriving from a poverty background” (Morris, 2020, p. 311). Poverty at its essence is a condition of scarcity. Daily choices must be made regarding which bills to pay and things that one must go without. The day-to-day struggle to survive and having to address immediate needs can result in the entrepreneur bringing a scarcity mindset to the venture creation process. Experienced scarcity has been associated with suboptimal decision-making and a short-term orientation (Mani et al, 2013; Shah et al., 2015). In addition, poverty can impose a number of disruptive demands that limit one’s ability to focus on building a business (Castellanza, 2020; Wilson, 2012). Examples can include the threat of eviction from one’s residence, gang violence, unexpected loss of a job, a chronic illness afflicting an uninsured family member, or a child’s school suspension or arbitrary arrest, among other everyday developments. The combination of a scarcity mindset and ongoing distractions can compromise the abilities to plan ahead, think strategically, and prepare for contingencies. Such conditions can represent a significant liability when attempting to navigate the complex demands and unanticipated developments encountered when developing a business. LOP and venture fragility Poverty conditions can have critical implications for the kinds of ventures created by those in poverty. Smith-Hunter and Boyd (2004) have suggested that labor market disadvantage coupled with resource disadvantage explains a tendency for the poor to create survivalist or marginal types of enterprises. Morris et al. (2018) argued that poverty conditions lead the poor to launch ventures that fall into the “commodity trap.” These are undifferentiated businesses that compete on price, are labor-intensive with high unit costs, and have limited capacity and small margins. They lack technology and key production equipment and have limited bargaining power with suppliers and customers. In short, disadvantages are likely to make the ventures of the poor more vulnerable and fragile, particularly following faulty business decisions or when encountering shocks and adverse circumstances (Van Ginneken, 2005). Fragility suggests the firm is less able to withstand these developments and more likely to be severely damaged or fail. The limited literature on organizational fragility centers on the financial structures of large, established firms that find themselves unable to effectively respond to economic crises. Researchers have explored how external threats make firms with risky balance sheets and few liquid assets more subject to financial collapse (Cueva et al., 2017; Den Haan et al., 2003). Fragility indicates that adverse circumstances can render the organization unable to perform its functions and meet the demands of stakeholders (Cómbita Mora, 2020; Wiklund et al., 2010). Among the few fragility studies involving small firms, Bottazzi et al. (2006) found the very smallest Italian businesses to be more fragile than firms in general. Madi (2013) explored how the relative fragility of micro and small enterprises in Brazil limited their ability to take advantage of the recovery following a global economic crisis. Bartik et al. (2020) demonstrated how the COVID-19 pandemic revealed higher than expected levels of small business fragility. As a dispositional property, we need to better understand the role of fragility in businesses created by those in poverty and the extent to which poverty circumstances contribute to this fragility. This brings us to the current research. Model and hypotheses How do the disadvantages conveyed by poverty influence the manner in which venture creation is approached and the fragility of the ventures created? To address this question, we propose the research model presented in Fig. 1. Here, LOP is captured by two elements that have received considerable attention in the poverty literature, experienced scarcity and a compromised ability to focus (Banerjee & Mullainathan, 2008; Bryan et al., 2017; Mullainathan & Shafir, 2013). Its impact on venture fragility is moderated by entrepreneurial alertness, or the individual’s ability, regardless of their resource endowment, to better recognize opportunities.Fig. 1 Research model Experienced scarcity can lead an individual to adopt a short-term orientation (Mani, et al, 2013). Shah et al., (2012, p. 682) argued that “scarcity creates its own mindset, changing how people look at problems and make decisions.” Immediate problems consume a disproportionate amount of the individual’s time, effort, and financial resources. Planning, anticipating, and preparing for future developments and needs and adopting a more strategic orientation become quite difficult (Banerjee & Mullainathan, 2008; Bryan et al., 2017; Wilson, 1996, 2012). In a venture context, the entrepreneur becomes more reactive or tactical in orientation, simply trying to address pressing operational needs. This sort of reactive, short-term perspective can make it difficult to think more holistically about where the business is going, set resources aside for contingencies, and build the sorts of sustained relationships that will enable the business to respond to threats and navigate through difficult times. A preoccupation with immediate problems can also mean the entrepreneur is not developing the knowledge and capabilities associated with key roles that must be filled within the enterprise, particularly roles unrelated to the problems at hand (Baum, 1996; George, 2005). Without sufficient planning, the firm cannot achieve economies in procurement and production. Such planning is also critical for the development of effective routines and procedures over time (Gong et al., 2004). As a result, the business is less prepared for adverse developments and its long-term sustainability is at risk. A scarcity mindset is coupled with the difficulties the entrepreneur has in focusing on the business. The poverty experience can introduce a range of distractions into the daily lives of entrepreneurs (Bryan et al., 2017; Morris, 2020). It becomes difficult to concentrate on the venture and dedicate the amount of time required if one is coping with medical emergencies, food shortages, threat of eviction from one’s home, shutoff of utilities, or criminal violence, among other nonbusiness demands. While the liability of newness suggests significant learning must take place as the entrepreneur assumes the numerous roles that come into play when building a business (Baum, 1996), these nonbusiness distractions undermine the ability to learn. Lack of complete focus on the enterprise is also likely to produce operational inefficiencies, less planning, and reduced bargaining power with stakeholders. Activities associated with key roles in the business may not receive attention, while the ability to formalize and adhere to key routines can be compromised. The legitimacy of the business can suffer as stakeholders question the entrepreneur’s dedication (Fisher et al., 2017). The result is a more fragile venture. Fragility in this context suggests that the LOP has made the venture more vulnerable to adverse internal or external developments and is unable to adequately respond when they occur. As a result, the venture becomes less able to perform key functions (Cómbita Mora, 2020; Wiklund et al., 2010). The entrepreneur struggles to afford inventory, pay expenses, meet payroll demands, serve customer needs, retain employees, maintain marketing efforts, or sustain relationships with external stakeholders (Morris et al., 2022). Faced with any sort of external threat, the absence of resource slack can force the entrepreneur to reduce capacity, sell assets, or otherwise undermine the ability to create value. The firm becomes more constrained, less competitive, and less economically viable (Madi, 2013). Based on this discussion, we hypothesize:H1: The entrepreneur’s LOP, as reflected in experienced scarcity and nonbusiness distractions, increases their venture’s fragility, such that higher levels of LOP are associated with a more fragile venture. Entrepreneurial alertness (EA) refers to the cognitions and behaviors that enable an individual to recognize opportunities (Gaglio & Katz, 2001). It involves the ability to scan and search for information, connect disparate pieces of information, and make evaluations regarding the existence of profitable business opportunities (Tang et al., 2012). Researchers have identified a range of situational (e.g., quality of social networks) and personal (e.g., experience, values, and traits) factors that can influence alertness (Pirhadi et al., 2021; Sharma, 2019). EA has been shown to be instrumental in achieving entrepreneurial outcomes in various contexts (Amato et al., 2017). Where the entrepreneur demonstrates greater alertness, opportunities for starting a venture and addressing setbacks as it develops are more readily recognized. The poverty experience can constrain an individual’s opportunity horizon (Alvarez & Barney, 2014; Morris et al., 2018). According to Berkman (2015), poverty restricts a person’s vision of what might be possible. It limits the information content to which one is exposed and imposes rules and norms regarding how things are done and how one gets ahead (Welter, 2011). However, aspects of the poverty experience might actually stimulate the individual’s alertness to opportunities (Light & Rosenstein, 1995). Examples include the ongoing need for creative solutions on how to feed or clothe one’s family when there is no money or the resiliency that results from confronting ongoing setbacks. Hence, while we might expect the poverty context to dampen one’s alertness (Chavoushi et al., 2021; Dana, 2007), differences in the relative levels of EA among those in poverty could have important implications. We posit that, when these levels are higher, EA can help reduce the negative impacts of the LOP when developing a venture. EA can enable individuals in poverty to recognize more promising opportunities. It enables them to develop behavioral patterns (e.g., asking questions, following the news, and searching for information) and cognitive abilities (e.g., connecting the dots, seeing environmental trends, and identifying patterns) through practice and social learning and leverage them to overcome challenges resulting from the LOP. For example, there is evidence suggesting that alertness serves as a vehicle for approaching problem-solving from a more strategic (Roundy et al., 2018), anticipatory (Neneh, 2019; Obschonka et al., 2017), and forward-looking (Tang et al., 2012) perspective, each of which could offset the short-term orientation resulting from scarcity and the reactiveness that results from nonbusiness distractions. This discussion produces the following hypothesis:H2: The positive effect of the entrepreneur’s LOP on their venture’s fragility is negatively moderated by EA, such that higher levels of EA reduce the positive influence of the LOP on venture fragility. Research methodology Data and sample A cross-sectional survey methodology was employed to test the research model. A self-report questionnaire was designed and administered to early-stage entrepreneurs who come from a poverty background. Access to the desired sample was facilitated by collaboration with a national program that seeks to empower low-income entrepreneurs in urban areas. This program leverages community resources in a number of cities to provide individuals who are often underserved by local entrepreneurial ecosystems with education, mentoring, and related support to help them start and develop businesses. We reached out to the population of 460 participants in this program in four cities during a 4-month period in early 2021. The cities were selected to reflect different geographic regions (the South, West, East, and Midwest) of the United States. Given reported problems in generating responses from low-income and disadvantaged subjects (Jackson & Ivanoff, 1998; Jang & Vorderstrasse, 2019), an incentive in the form of a $15 gift card was offered for participation. From this total, 226 individuals responded to the questionnaire, representing a response rate of 49%. After eliminating 24 surveys due to incompleteness, 202 surveys were used in the analysis. Within the final sample, 75% of responding entrepreneurs were female, a proportion similar to the overall makeup of the multicity program (see Table 2). The average age of respondents was 41 years. The number of family members living with the entrepreneur ranged from zero to eight (average of 2.7). The average venture age was 3.64 years. Measures Dependent variable Conventional financial ratios and related measures from financial statements employed in fragility studies (e.g., Bruneau et al., 2012; Tuzcuoğlu, 2020) tend not to be available for the ventures of the poor. As a result, we relied upon subjective indicators of fragility, similar to but more extensive than those utilized by Bartik et al. (2020). We consider three major characteristics from the literature that determine the extent to which a business is fragile (Bruneau et al., 2012; Cómbita Mora, 2020; Stonebraker et al., 2007). First, we measured a venture’s “ability to handle expenses” as a proxy for the business liquidity by asking four binary questions. Specifically, we asked the participants to determine, based on the amount of money in their business bank account, whether they could cover a $500 increase in operating expenses, including business rent; pay for a $1000 piece of important equipment; take advantage of a key market opportunity for their business that would require spending $5000; and purchase a used vehicle for the business that costs $10,000. The responses to these four questions were summed to determine the business’s ability to spend cash and cover expenses. Second, we measured the business’s “ability to generate profit” by asking participants approximately how much profit they earned each month over the past 6 months. The entrepreneurs could choose from five options: “none, we have just been breaking even or losing money in some months,” “a small monthly profit, under $1,000 per month,” “a moderate monthly profit, under $5,000 per month,” “a pretty good profit, under $10,000 per month,” or “we have done well, making more than $10,000 in profit per month.” Finally, we measured the business’s “ability to raise external funding” by asking participants, “if you needed to raise money for your business today, which of the following best describes your situation?” Entrepreneurs could choose from four options: “at present it would be very hard for me to qualify for a bank loan,” “I could probably qualify for a small bank loan (under $10,000),” “I could probably qualify for a bank loan of up to $50,000,” or “I could probably qualify for a bank loan of up to $100,000 or more.” These three measures were standardized and averaged to form an overall measure of “venture fragility,” where a higher score indicates a more fragile business. Independent variable LOP is a reflective construct that captures a multifaceted phenomenon (Morris, 2020; Roux et al., 2015; Shah et al., 2015). We focused on two major dimensions of LOP that represent unique aspects of living in poverty, namely, “experienced scarcity” and “nonbusiness distractions.” Bryan et al. (2017) argued that these represent two of the most well-documented psychological phenomena observed among those living in poverty circumstances. To measure experienced scarcity, we developed a set of 11 items that capture how scarcity is related to the ability to address basic needs (Chakravarty & D’Ambrosio, 2006; DeSousa et al., 2020). Sample items include “I have not sought the health/medical care I needed because I could not afford it” and “I sometimes have gone hungry because I could not afford to buy more food.” To measure nonbusiness distractions, six items were employed that reflect critical life demands when experiencing poverty (Mark et al., 2018; Reinholdt-Dunne et al., 2013). Examples include “I am often distracted by outside demands that make it hard to shift my attention back to the business” and “there are issues in my life which take my attention away from my business.” All items were measured using a 5-point Likert scale (“1 = strongly disagree” to “5 = strongly agree”). Moderating variable A commonly used scale developed by Tang et al. (2012) was adopted to measure EA. The scale measures three dimensions of EA: scanning and search, association and connection, and evaluation and judgment. All items were measured using a 5-point Likert scale (“1 = strongly disagree” to “5 = strongly agree”). Control variables Personal and business-related control variables were included in the analysis. At the individual level, the effects of participant’s age, gender, and family size were accounted for, as they have been shown to impact an individual’s ability to run a business (e.g., Gielnik et al., 2017; Rosa et al., 1996a, 1996b). In addition, the effects of venture age and venture size were controlled for. Younger and smaller ventures are inherently more fragile because they are subject to the liabilities of newness and smallness (Aldrich & Auster, 1986). We included two measures of venture size—the numbers of full-time and part-time employees—because these two employee categories have differing implications for a business (Soto‐Simeone et al., 2020). Analysis and results Measurement model An exploratory factor analysis (EFA) was performed to explore the data structure. Higher than recommended thresholds of the Kaiser–Meyer–Olkin (KMO) measure of sampling adequacy (KMO > 0.5) and significance of Bartlett’s test of sphericity (p < 0.001) suggested the data is suitable for factor analysis (Thompson, 2004). With the EFA, items with higher-than-0.5 factor loadings on the first principal component were chosen for each of the constructs (three items for venture fragility, six items for each component of LOP, and all items of EA). Then, a confirmatory factor analysis (CFA) was performed using the main latent constructs and their observed items to finalize our measures. Given the sample size and number of constructs, the measurement model was optimized by eliminating items with relatively lower factor loadings to ensure convergence of the structural equation model. This scale purification technique for multi-item measures is a common practice (Wieland et al., 2017). Table 1 presents the final set of items, standard factor loadings, average variance extracted (AVE), and Cronbach’s alphas for each construct. Significant and higher-than-0.4 factor loadings for all items suggest satisfactory convergent validity. In addition, the AVE for each construct was above 0.4 and higher than its common variance with any other construct, which indicates the discriminant validity thresholds were satisfied (Fornell & Larcker, 1981). The alphas for all constructs were also above 0.7, suggesting appropriate measure reliability. Moreover, the common fit indices for the CFA model (chi-square/degree of freedom = 1.62, CFI = 0.93, NNFI = 0.92, AGFI = 0.83, RMSEA = 0.05, and SRMR = 0.06) indicate acceptable fit between the measurement model and the data (Hooper et al., 2008). Overall, these results suggest valid and reliable measures that can be used for hypothesis testing.Table 1 Measurement models Item description Loading (t-score) Experienced scarcity (AVE = 0.43, Cronbach’s α = 0.79) I have not sought the health/medical care I needed because I could not afford it 0.62 (11.37) I have had to move in with friends/family because I could not afford to live on my own 0.62 (11.58) I sometimes go hungry because I cannot afford to buy more food 0.69 (14.07) I buy less nutritious foods because I cannot afford healthier options 0.70 (14.59) When thinking about buying something, I am always forced to consider other things I won’t be able to buy 0.63 (11.86) Nonbusiness distraction (AVE = 0.60, Cronbach’s α = 0.88) External demands make it difficult for me to focus on developing my business 0.73 (19.60) There are issues in my life which take my attention away from my business 0.74 (19.66) When I am working hard on my business, I still get distracted by demands outside the business 0.74 (19.69) I am often distracted by outside demands that make it hard to shift my attention back to the business 0.84 (31.20) It’s very hard for me to concentrate on my business when there are other things requiring my attention 0.83 (29.49) Liability of poorness (AVE = 0.45, Cronbach’s α = 0.84) Experienced scarcity 0.40 (3.11) Nonbusiness interactions 0.86 (3.65) Scanning and search (AVE = 0.51, Cronbach’s α = 0.83) I always keep an eye out for new business ideas when looking for information 0.62 (13.17) I read news, magazines, or trade publications regularly to acquire new information 0.62 (13.04) I browse the Internet every day 0.56 (10.72) I am an avid information seeker 0.80 (26.08) I am always actively looking for new information 0.92 (45.69) Association and connection (AVE = 0.60, Cronbach’s α = 0.82) I see links between seemingly unrelated pieces of information 0.75 (18.91) I am good at “connecting dots” 0.79 (21.57) I often see connections between previously unconnected domains of information 0.78 (21.12) Evaluation and judgment (AVE = 0.63, Cronbach’s α = 0.82) I can distinguish between profitable opportunities and not-so-profitable opportunities 0.79 (21.56) I have a knack for telling high-value opportunities apart from low-value opportunities 0.94 (29.76) When facing multiple opportunities, I am able to select the good ones 0.62 (12.67) Entrepreneurial alertness (AVE = 0.60, Cronbach’s α = 0.88) Scanning and search 0.91 (14.78) Association and connection 0.84 (13.61) Evaluation and judgment 0.52 (7.88) Venture fragility (AVE = 0.46, Cronbach’s α = 0.70) Ability to handle expenses 0.79 (12.63) Ability to generate profit 0.68 (10.97) Ability to raise external funding 0.52 (8.01) Fit indices: χ2/degree of freedom = 1.62, CFI = 0.93, NNFI = 0.92, AGFI = 0.83, RMSEA = 0.05, and SRMR = 0.06 Common method variance test Common method bias (CMB) tends to reduce the estimation of interaction effects (i.e., interaction effects are not artifacts of CMB). Hence, CMB is generally not a major concern in studies, such as the current one, that investigate interactions (Siemsen et al., 2010). Still, Harman’s single factor test was adopted to examine CMB issues. An EFA was performed using all measures while restricting the number of extracted factors to one. CMB can be a major concern if EFA results show that a significant part of the variance (> 50%) in the data is explained by a single factor (Podsakoff et al., 2003). Results indicated that less than 16% of the variance could be explained by one factor, suggesting no major CMB concerns. Hypotheses testing Descriptive statistics and correlations for all variables can be found in Table 2. Positive and significant correlations between both firm age and size and venture fragility suggest that, as expected, older and larger businesses are less fragile compared to younger and smaller ones. We standardized all variables and used hierarchical linear regression analysis for hypothesis testing.Table 2 Descriptive analysis Mean SD 1 2 3 4 5 6 7 8 1. Venture fragility 0.00 0.79 2. Venture age 3.64 4.50 − 0.15* 3. Venture size—full-time employees 0.97 1.29 − 0.11+ 0.12* 4. Venture size—part-time employees 0.90 1.72 − 0.23* 0.12+ 0.27* 5. Age 40.96 10.63 − 0.02 0.27* 0.04 0.10+ 6. Gender 0.79 0.41 0.29* − 0.05 0.03 − 0.15* 0.09+ 7. Household size 2.71 1.50 0.01 0.08 0.21 0.23 0.00 − 0.01 8. Liability of poorness (LOP) 2.98 0.76 0.24*** − 0.13* − 0.09 0.03 − 0.02 − 0.05 0.01 9. Entrepreneurial alertness (EA) 3.82 0.57 − 0.12* 0.03 0.07 0.04 − 0.10+ − 0.11+ 0.00 − 0.07 +p < 0.1, p < 0.05, p < 0.01, *p < 0.001 The analysis includes regression models built along three hierarchical steps. The base model includes all control variables. The main-effect model is formed by adding the main variables (i.e., LOP and EA) to the base model, and the contingency model includes an additional term for the interaction between LOP and EA. Regression assumptions were checked using common diagnostics and the significance of the R2 change was examined using the F test. Variance inflation factors (VIFs) were less than the suggested thresholds (VIFs < 1.17), indicating no multicollinearity issue with the models (Hair et al., 1998). Table 3 presents the results for the hierarchical regression analysis. The base model (R2 = 0.144, p < 0.001) explained 14.4% of the variance in venture fragility. As expected, the regression results suggest that venture age has a marginally significant and negative influence on fragility (β = − 0.12, p < 0.1), meaning that older firms tend to be less fragile. Regarding venture size, the results indicated no significant relationship between number of full-time employees and fragility (β = − 0.07, p > 0.1), but they did indicate a significant negative link between number of part-time employees and fragility (β = − 0.18, p < 0.05). These results are potentially important as they suggest employing part-time employees might be a more effective strategy for improving venture fragility, compared to full-time employees, as it provides greater flexibility and cost efficiency. Further, the relationship between gender and fragility is significant and positive (β = 0.26, p < 0.001), suggesting ventures run by women are more fragile.Table 3 Results for regression analysis Variables Base model Main-effect model Contingency model Controls β S.E β S.E β S.E ▪Venture age − 0.12+ 0.07 − 0.08 0.07 − 0.08 0.07 ▪Venture size—full-time employees − 0.07 0.07 − 0.05 0.07 − 0.04 0.07 ▪Venture size—part-time employees − 0.18 0.07 − 0.19 0.07 − 0.19 0.07 ▪Age 0.01 0.07 0.00 0.07 0.01 0.07 ▪Gender 0.26* 0.07 0.27* 0.07 0.27* 0.07 ▪Household size 0.08 0.07 0.07 0.07 0.07 0.07 Main effects ▪Liability of poorness (LOP) 0.24* 0.07 0.27*** 0.07 ▪Entrepreneurial alertness (EA) − 0.07 0.07 − 0.07 0.07 Interaction effect ▪LOP × EA − 0.13* 0.06 Models ΔR2 0.144* 0.061 0.016* R2 0.144 0.205 0.221 Adjusted R2 0.117 0.172 0.185 F 5.460* 6.208* 6.056*** Standardized regression coefficients are reported N = 202, +p < 0.1, p < 0.05, p < 0.01, **p < 0.001 The main-effect model (R2 = 0.205, p < 0.001) can explain the 6.1% additional variance in venture fragility (ΔR2 = 0.061, < 0.01). The model indicates that LOP has a significant and positive relationship with venture fragility (β = 0.24, p < 0.01). This result provides strong support for H1. In addition, the contingency model (R2 = 0.221, p < 0.001) can explain the 1.6% additional variability in venture fragility (ΔR2 = 0.016, p < 0.05). The interaction between LOP and EA has a significant and negative relationship with venture fragility (β = − 0.13, p < 0.05). This indicates that EA can weaken the positive influence of LOP on venture fragility, providing strong support for H2. We further examined this interaction effect by drawing graphs for the effect of LOP on venture fragility for low, medium, and high (− 1, 0, and + 1 standard deviation) levels of EA. As illustrated in Fig. 2, higher levels of LOP lead to the emergence of more fragile businesses and the slope of line is steeper when EA is lower, which suggests a stronger positive effect of LOP on venture fragility. Table 4 provides the conditional effects of LOP on venture fragility at low, medium, and high values of EA (Hayes, 2017). As shown in Table 4, LOP has a stronger positive effect on venture fragility when EA is low (β = 0.3979, p = 0.0001) compared to when EA is medium (β = 0.2724, p = 0.0001) or high ((β = 0.1469, p = 0.0631). As another robustness test, we performed a slope difference test suggested by Dawson (2014) to examine whether the effect of LOP on venture fragility is significantly higher than zero for low and high levels of EA and found consistent results that show the effect is stronger and significant when EA is low (β = 0.40, p = 0.0001), and weaker and non-significant when EA is high (β = 0.15, p = 0.10). In fact, the nonsignificant slope difference test for high levels of EA may suggest that the destructive effects of LOP on venture fragility can be totally avoided if the entrepreneur can develop high levels of EA. In sum, ventures run by entrepreneurs who experience similar levels of LOP may suffer from varying levels of fragility depending on their EA; the more entrepreneurially alert entrepreneurs are, the less their ventures are fragile because of their LOP.Fig. 2 Interactive effect of LOP and entrepreneurial alertness on venture fragility Table 4 Conditional effects of LOP on venture fragility at low/medium/high values of entrepreneurial alertness Entrepreneurial alertness Conditional effect S.E t value p value LLCI ULCI Low (− 1.00) 0.3979 0.1028 3.8698 0.0001 0.1951 0.6007 Medium (0.00) 0.2724 0.0671 4.0625 0.0001 0.1401 0.4046 High (1.00) 0.1469 0.0786 1.8693 0.0631 − 0.0081 0.3019 Discussion Poverty continues to have a pervasive impact on people’s lives across the globe (World Bank, 2021), with entrepreneurship proposed as a potential solution (Amorós et al., 2021; Sutter et al., 2019). This study has sought to examine how situational characteristics of poverty, as reflected in the LOP, influence ventures created by the poor. Where much of the empirical work on poverty and entrepreneurship has focused on developing economies, we focused on a developed economy context, where poverty rates have not meaningfully declined over 50 years. Using disadvantage theory, we generated a sample of entrepreneurs from poverty backgrounds to examine how the experience of scarcity and the nonbusiness distractions resulting from poverty conditions influence venture fragility. The results aligned with our research model and hypotheses. Both of these LOP factors lead entrepreneurs to create ventures that are more fragile. We further probe this relationship by examining a moderating effect. The results suggest higher levels of EA can lessen the impact of LOP on fragility. Thus, EA appears to compensate for the deleterious impact of poverty conditions on how the entrepreneur approaches venture creation. This study highlights the importance of a focus on venture fragility for advancing knowledge at the poverty and entrepreneurship interface. Research on small business fragility is quite limited. Based on the liabilities of newness and smallness (Hannan & Freeman, 1984; Stinchcombe, 1965), it can be argued that early-stage ventures are inherently fragile, at least more so than larger, better-established firms. Yet we find variability in fragility across our sample, suggesting there may be actions entrepreneurs can take which affect relative fragility, even in severely resource-constrained contexts. The abilities to set aside time for planning, not compromise future prospects by focusing purely on immediate needs, approach decision-making from a more holistic and strategic vantage point, and maintain focus in the face of significant nonbusiness demands would appear critical for developing a more resilient enterprise. The importance of fragility as an outcome warranting study is that it represents an ongoing state that reflects the extent to which the business is in serious trouble when the inevitable threat or unexpected development materializes. Other performance measures at a given point in time may not accurately reflect how precarious the business is. Significant revenue and profit declines following some disruptive event can be symptomatic of a business that is inherently more fragile, and it is this fragility that requires attention if the organization is to become more sustainable from a sales or profit vantage point. Fragility suggests the business cannot respond adequately to setbacks or disruptions and is unlikely to be sustainable. In addition, our findings advance disadvantage theory by showing how liabilities associated with poverty can directly extend to the venture creation process and can compromise the ability of these ventures to provide a pathway out of poverty. Prior scholarship has suggested that disadvantages associated with poverty can induce poor decision-making, resulting in sustained poverty and circumstances that keep individuals from pursuing entrepreneurship (Bryan et al., 2017; Sheehy-Skeffington & Rea, 2017). The current research goes a step further to demonstrate that when entrepreneurship is pursued, the result can be more fragile ventures, suggesting that more attention be placed on the situational constraints of poverty and their impacts across the venture development process. As a possible extension of disadvantage theory, we see the dual aspect of disadvantage at work; furthermore, we see that these dual forces are operating simultaneously and against one another. Disadvantage both drives and inhibits the individual, where the net effect is the creation of something new, but something that is marginalized in terms of constrained potential. Disadvantage creates a kind of dialectic, where the drive to rise above poverty is in opposition to the way one thinks and one’s ability to focus. While our emphasis has been on disadvantage, poverty also can produce certain assets, such as the motivation to escape poverty, resiliency from dealing with setbacks, and creativity in finding ways to survive and support a family (Light & Rosenstein, 1995; Morris & Tucker, 2021; Wilson, 2012). In a sense, poverty assets are in conflict with poverty liabilities. This brings us to alertness. There were entrepreneurs in our sample with higher levels of EA, where alertness contributed to making ventures less fragile. For its part, EA represents an individual-level capability that does not directly address disadvantage-induced fragility; instead, it interacts with the effects of poverty in ways that serve to counter the liability and perhaps accentuate the assets. While we did not measure the latter possibility, this is an important question for future research. It appears that the inhibiting aspects of disadvantage can push the individual into entrepreneurship (sometimes but not always out of necessity), often producing more marginal businesses, while the motivating aspects of disadvantage can pull the individual toward opportunity and creation of more sustainable ventures. As such, the linkage between disadvantage and opportunity recognition warrants further investigation (Alvarez & Barney, 2014; Baron & Ensley, 2006). Our findings add to the literature on EA (Tang et al., 2012), suggesting that alertness can be leveraged as a resource among poverty entrepreneurs, allowing them to expand the range of possibilities for their ventures. This implies that, while poverty might be a situational phenomenon, there are individual-level factors that can offset the disadvantages associated with poverty. The challenge is to develop richer insights into how the depth and breadth of the opportunity horizons of those in poverty contexts can be expanded. Furthermore, new insights are needed into how to nurture among the disadvantaged the cognitive abilities and behavioral patterns required for EA (Hajizadeh & Zali, 2016; Ozgen & Baron, 2007). Empowering these individuals to expand their opportunity horizons and see more possibilities in their lives can complement public efforts to remove institutional barriers that cause social exclusion and discrimination, thereby helping to develop a more equal and inclusive society. Our findings regarding gender are also noteworthy. The fact that women entrepreneurs in our sample created more fragile businesses is consistent with previous findings. Different studies have found that female-owned firms were more likely than those owned by males to close, and had lower levels of sales, profits, and employment (Kalleberg & Leicht, 1991; Robb & Wolken, 2002; Robb, 2002; Rosa et al., 1996a, 1996b). While these performance differences have been attributed to race, education and training, work experience, access to capital, and type of industry (see Fairlie & Robb, 2008 for a comprehensive review), poverty represents an additional explanation. Hence, the disadvantages confronted by women in general would appear to be exacerbated by poverty conditions, consistent with our arguments about the liabilities of poorness. As the literature stresses the emphasis by women entrepreneurs on balance between work demands and family (e.g., Agarwal & Lenka, 2015; Coleman, 2016), the difficulties in focusing on the business due to family-related distractions (e.g., effects on family members of chronic illness, food scarcity, gang influences, physical insecurity, and so forth) might be especially important in this regard. Turning to implications for practice, the poor begin at a disadvantage when they launch ventures. This disadvantage is exacerbated by the lack of infrastructure in poorer communities and the failure of entrepreneurial ecosystems to adequately support those in poverty (Neumeyer et al., 2019; Weyers et al., 2008). Part of the challenge here is the need to tailor assistance and support to reflect the LOP and its implications for the creation of sustainable enterprises. Experienced scarcity represents a case in point. If exposed to a prolonged period of scarcity, where one is preoccupied with short-term family survival, tradeoffs must regularly be made in what expenses are paid, and immediate exigencies take precedence over consideration for the longer-term implications of decisions. Forced to confront a host of novel issues in an unfamiliar context (i.e., a start-up venture), the entrepreneur struggles to take the kinds of actions that will produce a sustainable enterprise. It is not enough to tell the entrepreneur how important it is to plan or engage in strategic thinking. Assistance is needed in setting priorities, knowing what can and cannot be sacrificed in the short term, recognizing the interdependencies among decisions in different areas of a business, and understanding intermediate and longer-term costs of trade-off decisions. Training, mentoring, and other forms of support can also help the entrepreneur appreciate the kinds of short-term actions that can lessen venture fragility. Similar implications can be drawn regarding nonbusiness distractions. The single mother who is working two part-time jobs while attempting to develop a business struggles to find the time to creatively leverage resources, develop novel marketing methods, or try a new production approach. She is not only the prime source of labor in what is typically a labor-intensive business, but is distracted by a host of poverty-related circumstances This represents a scenario where more enlightened public policies combined with local ecosystems that are more poverty-inclusive can play a significant role. Whether through subsidized childcare, income subsidies tied to venture progress, vouchers to cover the costs of part-time employees through the first two years of a venture, mentor–protégé programs connecting the entrepreneur to established businesses in the industry, or other creative approaches, the ability of the low-income entrepreneur to focus on venture priorities can be enhanced in ways that support sustainability. Limitations and future research directions These findings must be interpreted with the limitations of the study in mind. Among these is the subjective nature of the measures employed. We asked respondents to self-report their levels of experienced scarcity and nonbusiness distractions and relied on subjective indicators of venture fragility. Regarding fragility, while we attempted to rectify this concern by developing items based on prior literature, an objective measure of venture fragility might better serve the ability to capture the effects of poverty on venture outcomes. Poverty is a complex phenomenon experienced uniquely by individuals. While all study participants came from a poverty background, we did not ascertain the extent of their poverty circumstances. Our measure of the LOP can potentially serve as a proxy indicator, but future studies might explore how various dimensions of poverty (e.g., housing stability, food security, and chronic health problems) affect those being studied. A related limitation is the lack of entrepreneurs in the sample who are not experiencing poverty. Hence, while we compared the fragility of businesses created by those who suffer varying levels of the LOP, we could not compare how fragility differs between entrepreneurs who do and do not come from poverty backgrounds. In particular, as most start-ups are arguably to some degree fragile, such a comparison would reinforce the relationship between poverty and fragility. Finally, the cross-sectional nature of our study prevents us from understanding how the effects of poverty influence venture performance over time. Because we asked about ventures at one point in time, we lack insights into the temporal relationship between poverty and venture development. This issue is important for several reasons. First, it is unclear how (e.g., through learning during the venture development process) entrepreneurs may be able to outgrow the effects of poverty, or whether these effects remain pernicious throughout a venture’s life. Second, we assumed that less fragile ventures could provide a pathway out of poverty without being able to capture how reductions in venture fragility contribute over time to the entrepreneur’s well-being. Similarly, our research method does not allow us to infer whether and how venture fragility might actually worsen poverty conditions over time. Based on the results, a number of important avenues for future research can be identified. Our findings suggest a need to further investigate factors that can improve or exacerbate venture fragility. Examples include characteristics of the entrepreneur (e.g., literacy and skills) and business-related factors (e.g., resourcing strategies). The results also suggest that females tend to create more fragile ventures, but richer insights are needed into possible institutional, venture-related, personal or situational factors that could help explain this gender gap. While we explored the impact of EA, scholars might further examine the opportunity horizons of those in poverty. The issue may not simply be how alert one is to opportunities, but their alertness to higher potential opportunities. An associated question concerns how the pursuit of entrepreneurship affects opportunity horizons. The ability to escape the commodity trap and build a sustainable enterprise is tied to adaptation and acting upon new opportunities as they emerge (Morris et al., 2012; Ronstadt, 1988). To what extent does the venture experience itself change or improve the opportunities the entrepreneur is able to perceive? Lastly, researchers might further explore the implications of fragility. Does it lead to more conservatism in decision-making, missed opportunities, and less adaptation, such that fragility results in behaviors that contribute to even greater fragility? Does it limit the socioeconomic mobility of the entrepreneur, such that addressing venture fragility becomes the key to entrepreneurship as a viable pathway out of poverty? These possibilities suggest a need for parallel investigations into both venture outcomes and family outcomes and, with the latter, research that explores multigenerational effects. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Acs, Z. J. & Kallas, K. (2008). State of literature on small- to medium-sized enterprises and entrepreneurship in low-income communities. In: Yago, G., Barth, J. R., & Zeidman, B. (eds.). Entrepreneurship in emerging domestic markets. Springer–Milken Institute. 10.1007/978-0-387-72857-5_3 Acs ZJ Szerb L Entrepreneurship, economic growth and public policy Small Business Economics 2007 28 2–3 109 122 10.1007/s11187-006-9012-3 Agarwal S Lenka U Study on work-life balance of women entrepreneurs – review and research agenda Industrial and Commercial Training 2015 47 7 356 362 10.1108/ICT-01-2015-0006 Aldrich HA Auster E Staw B Cummings LL Even dwarf started small: Liabilities of size and age and their strategic implications Research in Organizational Behavior, 8 1986 JAI Press 165 198 Alvarez SA Barney JB Entrepreneurial opportunities and poverty alleviation Entrepreneurship Theory and Practice 2014 38 1 159 184 10.1111/etap.12078 Amato C Baron RA Barbieri B Belanger JJ Pierro A Regulatory modes and entrepreneurship: The mediational role of alertness in small business success Journal of Small Business Management 2017 55 sup1 27 42 10.1111/jsbm.12255 Amorós, J. E., Ramírez, L. M., Rodríguez-Aceves, L., & Ruiz, l. E. (2021). Revisiting poverty and entrepreneurship in developing countries. Journal of Developmental Entrepreneurship, 2150008. 10.1142/S1084946721500084 Bandiera, O., Burgess, R., Das, N., Gulesci, S., Rasul, I., & Sulaiman, M. (2013). Can basic entrepreneurship transform the economic lives of the poor? 10.2139/ssrn.2266813 Banerjee, A.V., & Duflo, E. (2011). Poor economics: a radical rethinking of the way to fight global poverty. Public Affairs. Banerjee AV Mullainathan S Limited attention and income distribution American Economic Review 2008 98 2 489 493 10.1257/aer.98.2.489 Baron RA Ensley MD Opportunity recognition as the detection of meaningful patterns: Evidence from comparisons of novice and experienced entrepreneurs Management Science 2006 52 9 1331 1344 10.1287/mnsc.1060.0538 Bartik AW Bertrand M Cullen Z Glaeser EL Luca M Stanton C The impact of COVID-19 on small business outcomes and expectations Proceedings of the National Academy of Sciences 2020 117 30 17656 17666 10.1073/pnas.2006991117 Baum JAC Clegg S Hardy C Nord WR Organizational ecology Handbook of Organizational Studies 1996 Sage 77 114 Berkman, E. (2015). Poor people don’t have less self-control. Poverty forces them to think short-term. New Republic (September 22). Retrieved from https://newrepublic.com/article/122887/poor-people-don’t-have-less-self-control Bottazzi, G., Secchi, A., Tamagni, F. (2006). Financial fragility and growth dynamics of Italian business firms (No. 2006/07). LEM Working Paper Series. http://hdl.handle.net/10419/89394 Boyd, R. (2000). Survivalist entrepreneurship among urban blacks during the Great Depression: a test of the disadvantage theory of business enterprise. Social Science Quarterly, 972–984. https://www.jstor.org/stable/42864032 Bruneau C de Bandt O El Amri W Macroeconomic fluctuations and corporate financial fragility Journal of Financial Stability 2012 8 4 219 235 10.1016/j.jfs.2012.02.002 Bruton GD Ketchen DJ Ireland RD Entrepreneurship as a solution to poverty Journal of Business Venturing 2013 28 6 683 689 10.1016/j.jbusvent.2013.05.002 Bruton GD Ahlstrom D Si S Entrepreneurship, poverty, and Asia: moving beyond subsistence entrepreneurship Asia Pacific Journal of Management 2015 32 1 22 10.1007/s10490-014-9404-x Bruton G Sutter C Lenz AK Economic inequality—is entrepreneurship the cause or the solution? A review and research agenda for emerging economies Journal of Business Venturing 2021 36 3 106095 10.1016/j.jbusvent.2021.106095 Butler, J. S. (1991). Entrepreneurship and self-help among black Americans. State University of New York Press. Bryan CJ Mazar N Jamison J Braithwaite J Dechausay N Fishbane A Fox E Gauri V Glennerster R Haushofer J Vakis R Overcoming behavioral obstacles to escaping poverty Behavioral Science & Policy 2017 3 1 80 91 10.1353/bsp.2017.0007 Castellanza, L. (2020). Discipline, abjection, and poverty alleviation through entrepreneurship: a constitutive perspective. Journal of Business Venturing, 106032. 10.1016/j.jbusvent.2020.106032 Chakravarty SR D’Ambrosio C The measurement of social exclusion Review of Income and Wealth 2006 52 3 377 398 10.1111/j.1475-4991.2006.00195.x Chavoushi ZH Zali MR Valliere D Faghih N Hejazi R Dehkordi AM Entrepreneurial alertness: A systematic literature review Journal of Small Business & Entrepreneurship 2021 33 2 123 152 10.1111/j.1468-4446.2012.01419.x Chetty R Hendren N The impacts of neighborhoods on intergenerational mobility II: County-level estimates The Quarterly Journal of Economics 2018 133 3 1163 1228 10.1093/qje/qjy006 Chronic Poverty Research Centre. (2009). The chronic poverty report 2008–09: escaping poverty traps. Chronic Poverty Research Centre. Coleman S Connerley ML Wu J Gender, entrepreneurship, and firm performance: Recent research and considerations of context Handbook on Well-Being of Working Women 2016 Springer Science 375 391 Cómbita Mora G Structural change and financial fragility in the Colombian business sector: a post Keynesian approach Cuadernos de Economía 2020 39 80 567 594 10.15446/cuad.econ.v39n80.82562 Cooper, A.C., & Dunkelberg, W. (1987) Entrepreneurial research: old questions, new answers and methodological issues. American Journal of Small Business (Winter), 11–22. 10.1177/104225878701100301 Cueva, D., Cortes, S, Tapia, R, Tabi, w., Torres, J, Maza, C., Uyaguari, K., & Gonzalez, M (2017). Financial fragility of companies—estimation of a probabilistic model LOGIT and PROBIT: Ecuadorian case. 12th Iberian Conference on Information Systems and Technologies (CISTI), Lisbon, 2017, 1–6. 10.23919/CISTI.2017.7975927 Dana, L. P. (2007). Handbook of research on ethnic minority entrepreneurship: a co-evolutionary view on resource management. Edward Elgar Publishing. 10.4337/9781847209962 Dawson JF Moderation in management research: What, why, when and how Journal of Business and Psychology 2014 29 1 19 10.1007/s10869-013-9308-7 Den Haan WJ Ramey G Watson J Liquidity flows and fragility of business enterprises Journal of Monetary Economics 2003 50 6 1215 1241 10.1016/S0304-3932(03)00077-1 Dermott E Pomati M ‘Good’ parenting practices: How important are poverty, education and time pressure? Sociology 2016 50 1 125 142 10.1177/0038038514560260 DeSousa M Reeve CL Peterman AH Development and initial validation of the Perceived Scarcity Scale Stress and Health 2020 36 2 131 146 10.1002/smi.2908 31692256 Fairlie, R. & Robb, A. (2008). Gender differences in business performance: evidence from the characteristics of business owners survey. IZA Discussion Paper 3718, Bonn: Institute for the Study of Labor. https://repec.iza.org/dp3718.pdf. Fisher G Kuratko DF Bloodgood J Hornsby JS Legitimate to whom? Audience diversity and individual level new venture legitimacy judgments Journal of Business Venturing 2017 32 1 52 71 10.1016/j.jbusvent.2016.10.005 Fornell C Larcker DF Evaluating structural equation models with unobservable variables and measurement error Journal of Marketing Research 1981 18 1 39 50 10.1177/002224378101800104 Gaglio CM Katz JA The psychological basis of opportunity identification: Entrepreneurial alertness Small Business Economics 2001 16 2 95 111 10.1023/A:1011132102464 George G Slack resources and the performance of privately held firms Academy of Management Journal 2005 48 4 661 676 10.5465/amj.2005.17843944 Gielnik MM Zacher H Schmitt A How small business managers’ age and focus on opportunities affect business growth: A mediated moderation growth model Journal of Small Business Management 2017 55 3 460 483 10.1111/jsbm.12253 Gong, Y., Baker, T., & Miner, A. S., (2004). Where do routines come from in new ventures? Proceedings, Academy of Management Annual Meetings, New Orleans, LA. Hair JF Anderson RE Tathum RL Black WC Multivariate data analysis with readings 1998 Macmillan Hajizadeh, A., & Zali, M. (2016). Prior knowledge, cognitive characteristics and opportunity recognition. International Journal of Entrepreneurial Behavior & Research. 10.1108/IJEBR-05-2015-0110 Hannan MT Freeman J Structural inertia and organizational change American Sociology Review 1984 49 149 164 10.2307/2095567 Hayes, A. F. (2017). Introduction to mediation, moderation, and conditional process analysis: a regression-based approach. Guilford publications. Hernandez DJ Double jeopardy: how third grade reading skills and poverty influence high school graduation 2011 ERIC, April, Baltimore, MD Annie E Casey Foundation Herring C Open for business in the black metropolis: Race, disadvantage, and entrepreneurial activity in Chicago’s inner city The Review of Black Political Economy 2004 31 4 35 57 10.1007/s12114-004-1009-z Hooper, D., Coughlan, J., & Mullen, M. R. (2008). Evaluating model fit: a synthesis of the structural equation modelling literature. In: 7th European conference on research methodology for business and management studies,195–200. Horton H De Jong G Black entrepreneurs: A socio-demographic analysis Research in Race and Ethnic Relations 1991 6 105 120 Jackson AP Ivanoff A Reduction of low response rates in interview surveys of poor African-American families Journal of Social Service Research 1998 25 1–2 41 60 10.1300/J079v25n01_03 Jackson W Marino L Naidoo J Tucker R Size matters: impact of loan size on measures of disparate treatment toward minority entrepreneurs in the small firm credit market Entrepreneurship Research Journal 2018 8 4 10.1515/erj-2018-0129 Jang M Vorderstrasse A Socioeconomic status and racial or ethnic differences in participation: Web-based survey JMIR Research Protocols 2019 8 4 e11865 10.2196/11865 30969173 John, D., & Poisner D. (2016). The power of broke. Currency Publishing. Kalleberg A Leicht K Gender and organizational performance: Determinants of small business survival and success Academy of Management Journal 1991 34 1 136 161 10.5465/256305 Kay AC Gaucher D Peach JM Laurin K Friesen J Zanna MP Spencer SJ Inequality, discrimination, and the power of the status quo Journal of Personality and Social Psychology 2009 97 3 421 10.1037/a0015997 19685999 Kirzner IM Creativity and/or alertness: A reconsideration of the Schumpeterian entrepreneur The Review of Austrian Economics 1999 11 1 5 17 10.1023/A:1007719905868 Krishna A Escaping poverty and becoming poor: Who gains, who loses, and why? World Development 2004 32 1 121 136 10.1016/j.worlddev.2003.08.002 Kuppuswamy V Younkin P Testing the theory of consumer discrimination as an explanation for the lack of minority hiring in Hollywood films Management Science 2020 66 3 1227 1247 10.1287/mnsc.2018.3241 Light I Disadvantaged minorities in self-employment International Journal of Comparative Sociology 1979 20 1–2 31 45 Light, I. H., & Rosenstein, C. N. (1995). Race, ethnicity, and entrepreneurship in urban America. Transaction Publishers. Madi MAC Micro and small business in Brazil: Asymmetries and financial fragility International Journal of Globalisation and Small Business 2013 5 3 136 147 10.1504/IJGSB.2013.054889 Maldonado LC Nieuwenhuis R Family policies and single parent poverty in 18 OECD countries, 1978–2008 Community, Work & Family 2015 18 4 395 415 10.1080/13668803.2015.1080661 Mani A Mullainathan S Shafir E Zhao J Poverty impedes cognitive function Science 2013 341 6149 976 980 10.1126/science.1238041 23990553 Mark, G., Czerwinski, M., & Iqbal, S.T. (2018). Effects of individual differences in blocking workplace distractions. Proceedings of the CHI Conference on Human Factors in Computing Systems: 1–12. New York: ACM. 10.1145/3173574.3173666 Morland K Wing S Diez Roux A Poole C Neighborhood characteristics associated with location of food stores and food service places American Journal of Preventive Medicine 2002 22 1 23 29 10.1016/S0749-3797(01)00403-2 11777675 Morris MH The liability of poorness: Why the playing field is not level for poverty entrepreneurs Poverty and Public Policy 2020 12 3 304 315 10.1002/pop4.283 Morris MH Kuratko DF Schindehutte M Spivack AJ Framing the entrepreneurial experience Entrepreneurship Theory and Practice 2012 36 1 11 40 10.1111/j.1540-6520.2011.00471.x Morris, M. H., Santos, S. C., & Neumeyer, X. (2018). Poverty and entrepreneurship in developed economies. Edward Elgar Publishing. Morris, M.H., & Tucker, R. (2021). The entrepreneurial mindset and poverty. Journal of Small Business Management, 1–30. 10.1080/00472778.2021.1890096 Morris MH Kuratko DF Audretsch DB Santos S Overcoming the liability of poorness: Disadvantage, fragility and the poverty entrepreneur Small Business Economics 2022 58 1 41 55 10.1007/s11187-020-00409-w Mullainathan S Shafir E Scarcity: Why having too little means so much 2013 Macmillan Nakara WA Messeghem K Ramaroson A Innovation and entrepreneurship in a context of poverty: A multilevel approach Small Business Economics 2021 56 1601 1617 10.1007/s11187-019-00281-3 Naminse EY Zhuang J Does farmer entrepreneurship alleviate rural poverty in China? Evidence from Guangxi Province PLOS One 2018 13 3 e0194912 10.1371/journal.pone.0194912 29596517 Neneh BN From entrepreneurial alertness to entrepreneurial behavior: The role of trait competitiveness and proactive personality Personality and Individual Differences 2019 138 273 279 10.1016/j.paid.2018.10.020 Neumeyer X Santos SC Morris MH Who is left out: Exploring social boundaries in entrepreneurial ecosystems The Journal of Technology Transfer 2019 44 2 462 484 10.1007/s10961-018-9694-0 Neumeyer X Santos SC Morris MH Overcoming barriers to technology adoption when fostering entrepreneurship among the poor: The role of technology and digital literacy IEEE Transactions on Engineering Management 2021 68 6 1605 1618 10.1109/TEM.2020.2989740 Obschonka M Hakkarainen K Lonka K Salmela-Aro K Entrepreneurship as a twenty-first century skill: Entrepreneurial alertness and intention in the transition to adulthood Small Business Economics 2017 48 3 487 501 10.1007/s11187-016-9798-6 Odeku KO The plight of women entrepreneurs during covid-19 pandemic lockdown in South Africa Gender & Behaviour 2020 18 3 16068 16074 Ozgen E Baron RA Social sources of information in opportunity recognition: Effects of mentors, industry networks, and professional forums Journal of Business Venturing 2007 22 2 174 192 10.1016/j.jbusvent.2005.12.001 Piaseu N Mitchell P Household food insecurity among urban poor in Thailand Journal of Nursing Scholarship 2004 36 2 115 121 10.1111/j.1547-5069.2004.04023.x 15227757 Payne RK DeVol P Smith TD Bridges out of poverty 2006 Process Inc Pirhadi, H., Soleimanof, S., & Feyzbakhsh, A. (2021). Unpacking entrepreneurial alertness: how character matters for entrepreneurial thinking. Journal of Small Business Management, 1–32. 10.1080/00472778.2021.1907584 Podsakoff PM MacKenzie SB Lee JY Podsakoff NP Common method biases in behavioral research: A critical review of the literature and recommended remedies Journal of Applied Psychology 2003 88 5 879 10.1037/0021-9010.88.5.879 14516251 Reinholdt-Dunne ML Mogg K Bradley BP Attention control: Relationships between self-report and behavioural measures, and symptoms of anxiety and depression Cognition & Emotion 2013 27 3 430 440 10.1080/02699931.2012.715081 22917576 Rosa P Carter S Hamilton D Gender as a determinant of small business performance: Insights from a British study Small Business Economics 1996 8 463 478 10.1007/BF00390031 Robb A Entrepreneurship: A path for economic advancement for women and minorities? Journal of Developmental Entrepreneurship 2002 7 4 383 397 Robb, A. & Wolken, J. (2002) Firm, owner, and financing characteristics: differences between female- and male-owned small businesses, Federal Reserve Working Paper Series: 2002–18. https://papers.ssrn.com/sol3/papers.cfm?abstract_id=306800 Rockinson-Szapkiw AJ Spaulding L Spaulding M Identifying significant integration and institutional factors that predict online doctoral persistence The Internet and Higher Education 2016 31 101 112 10.1016/j.iheduc.2016.07.003 Ronstadt R The corridor principle Journal of Business Venturing 1988 3 1 31 40 10.1016/0883-9026(88)90028-6 Rosa P Carter S Hamilton D Gender as a determinant of small business performance: Insights from a British study Small Business Economics 1996 8 6 463 478 10.1007/BF00390031 Roundy PT Harrison DA Khavul S Pérez-Nordtvedt L McGee JE Entrepreneurial alertness as a pathway to strategic decisions and organizational performance Strategic Organization 2018 16 2 192 226 10.1177/1476127017693970 Roux C Goldsmith K Bonezzi A On the psychology of scarcity: When reminders of resource scarcity promote selfish (and generous) behavior Journal of Consumer Research 2015 42 4 615 631 10.1093/jcr/ucv048 Sadler MA Escaping poverty: Risk-taking and endogenous inequality in a model of equilibrium growth Review of Economic Dynamics 2000 3 4 704 725 10.1006/redy.1999.0088 Santos SC Neumeyer X Morris MH Entrepreneurship education in a poverty context: An empowerment perspective Journal of Small Business Management 2019 57 6 32 10.1111/jsbm.12485 Shah AK Shafir E Mullainathan S Scarcity frames value Psychological Science 2015 26 4 402 412 10.1177/0956797614563958 25676256 Shah AK Mullainathan S Shafir E Some consequences of having too little Science 2012 338 6107 682 685 10.1126/science.12224 23118192 Shane S Kolvereid L Westhead P An exploratory examination of the reasons leading to new firm formation across country and gender Journal of Business Venturing 1991 6 6 431 446 10.1016/0883-9026(91)90029-D Shane S Why encouraging more people to become entrepreneurs is bad public policy Small Business Economics 2009 33 2 141 149 10.1007/s11187-009-9215-5 Sharma L A systematic review of entrepreneurial alertness Entrepreneurship in Emerging Economies 2019 11 2 217 233 10.1108/JEEE-05-2018-0049 Shepherd DA Parida V Wincent J Entrepreneurship and poverty alleviation: The importance of health and children’s education for slum entrepreneurs Entrepreneurship Theory and Practice 2021 45 2 350 385 10.1177/1042258719900774 Sheehy-Skeffington, J., & Rea, J. (2017). How poverty affects people’s decision-making processes. Joseph Rowntree Foundation. Siemsen E Roth A Oliveira P Common method bias in regression models with linear, quadratic, and interaction effects Organizational Research Methods 2010 13 3 456 476 10.1177/1094428109351241 Silverman RM Black business, group resources, and the economic detour: Contemporary Black manufacturers in Chicago’s ethnic beauty aids industry Journal of Black Studies 1999 30 2 232 258 10.1177/002193479903000206 Slivinski, S. (2012). Goldwater Institute policy report: increasing entrepreneurship is a key to lowering poverty rates (No. 254). Report. Smith-Hunter AE Boyd RL Applying theories of entrepreneurship to a comparative analysis of white and minority business owners Women in Management Review 2004 19 1/2 18 28 10.1108/09649420410518403 Soto-Simeone A Sirén C Antretter T New venture survival: A review and extension International Journal of Management Reviews 2020 22 4 378 407 10.1111/ijmr.12229 Stinchcombe, A.L. (1965). Social structure and organizations. In: Handbook of organizations. Rand McNally. 142–193. Stonebraker, W. P., Goldhar, J., & Nassos, G., (2007). Toward a framework of supply chain sustainability: the fragility index. Proceedings. Production Operation Management Annual Conference (May). 1–27 Sutter C Bruton GD Chen J Entrepreneurship as a solution to extreme poverty: A review and future research directions Journal of Business Venturing 2019 34 1 197 214 10.1016/j.jbusvent.2018.06.003 Tang J Kacmar KMM Busenitz L Entrepreneurial alertness in the pursuit of new opportunities Journal of Business Venturing 2012 27 1 77 94 10.1016/j.jbusvent.2010.07.001 Thompson B Exploratory and confirmatory factor analysis: Understanding concepts and applications 2004 American Psychological Association Tirado L Hand to mouth: Living in bootstrap America 2015 Penguin Tuzcuoğlu T The impact of financial fragility on firm performance: An analysis of BIST companies Quantitative Finance and Economics 2020 4 2 310 342 10.3934/QFE.2020015 Van Ginneken W Managing risk and minimizing vulnerability: The role of social protection in pro-poor growth 2005 ILO Von Braun, J., Vargas Hill, R., & Pandya-Lorch, R. (2009). The poorest and hungry: assessments, analyses and action: an IFPRI 2020 book. International Food Policy Research Institute. 10.2499/9780896296602BK Walton, A. (2018). How poverty changes your mindset. Chicago Booth Review. Retrieved from http://review.chicagobooth.edu/behavioralscience/2018/article/how-poverty-changes-your-mind-set. Webb J Bruton G Tihanyi L Ireland RD Research on entrepreneurship in the informal economy: Framing a research agenda Journal of Business Venturing 2013 28 5 598 614 10.1016/j.jbusvent.2012.05.003 Welter F Contextualizing entrepreneurship: Conceptual challenges and ways forward Entrepreneurship Theory and Practice 2011 35 1 165 184 10.1111/j.1540-6520.2010.00427.x Weyers S Dragano N Möbus S Beck EM Stang A Möhlenkamp S Heinz K Jöckel R Siegrist J Low socio-economic position is associated with poor social networks and social support International Journal for Equity in Health 2008 7 1 13 10.1186/1475-9276-7-13 18457583 Wieland A Durach CF Kembro J Treiblmaier H Statistical and judgmental criteria for scale purification Supply Chain Management: An International Journal 2017 22 4 321 328 10.1108/SCM-07-2016-0230 Wiklund J Baker T Shepherd D The age-effect of financial indicators as buffers against the liability of newness Journal of Business Venturing 2010 25 4 423 437 10.1016/j.jbusvent.2008.10.011 Williams JM Bryan J Morrison S Scott TR Protective factors and processes contributing to the academic success of students living in poverty: Implications for counselors Journal of Multicultural Counseling and Development 2017 45 3 183 200 10.1002/jmcd.12073 Wilson WJ When work disappears 1996 Vintage Books Wilson WJ The truly disadvantaged: The inner city, the underclass, and public policy 2012 University of Chicago Press World Bank (2021). Poverty data. https://data.worldbank.org/topic/poverty. Younkin P Kuppuswamy V Discounted: The effect of founder race on the price of new products Journal of Business Venturing 2019 34 2 389 412 10.1016/j.jbusvent.2018.02.004
PMC009xxxxxx/PMC9484840.txt	==== Front J Nucl Cardiol J Nucl Cardiol Journal of Nuclear Cardiology 1071-3581 1532-6551 Springer International Publishing Cham 36123566 3090 10.1007/s12350-022-03090-6 Original Article Detection of acute myocarditis by ECG-triggered PET imaging of somatostatin receptors compared to cardiac magnetic resonance: preliminary results Boursier Caroline MD [email protected] 13 Chevalier Elodie MD 1 Varlot Jeanne MD 2 Filippetti Laura MD 2 Huttin Olivier MD, PhD 2 Roch Véronique MSc 1 Imbert Laetitia PhD 13 Albuisson Eliane MD, PhD 5 Claudin Marine MD 1 Mandry Damien MD, PhD 34 Marie Pierre-Yves MD, PhD 16 1 grid.29172.3f 0000 0001 2194 6418 Department of Nuclear Medicine and Nancyclotep Imaging Platform, CHRU Nancy, Université de Lorraine, 54000 Nancy, France 2 grid.410527.5 0000 0004 1765 1301 Department of Cardiology, CHRU Nancy, 54000 Nancy, France 3 grid.29172.3f 0000 0001 2194 6418 IADI, INSERM U1254, Université de Lorraine, 54000 Nancy, France 4 grid.29172.3f 0000 0001 2194 6418 Department of Radiology, Brabois, CHRU Nancy, Université de Lorraine, 54000 Nancy, France 5 grid.410527.5 0000 0004 1765 1301 Unit of Methodology, Data Management, Statistics, DRCI, Department MPI, UMDS, CHRU-Nancy, 54000 Nancy, France 6 grid.29172.3f 0000 0001 2194 6418 INSERM, UMR 1116, Université de Lorraine, 54000 Nancy, France 19 9 2022 2023 30 3 10431049 4 5 2022 18 7 2022 © The Author(s) under exclusive licence to American Society of Nuclear Cardiology 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Abstract Somatostatin receptors are overexpressed by inflammatory cells but not by cardiac cells, under normal conditions. This study assesses the detection of acute myocarditis by the ECG-triggered digital-PET imaging of somatostatin receptors (68Ga-DOTATOC-PET), as compared to Cardiac Magnetic Resonance (CMR) imaging, which is the reference diagnostic method in this setting. Methods Fourteen CMR-defined acute myocarditis patients had a first 15-minutes ECG-triggered 68Ga-DOTATOC PET recording, 4.4 ± 3.0 days from peak troponin, and 10 had a second 4.3 ± 0.3 months later. Myocardial/blood SUVmax ratio was analyzed relative to the normal upper limit of 2.18, which had been previously determined from oncology 68Ga-DOTATOC-PET recordings of patients with a similar age range as the myocarditis patients. Results An increased myocardial 68Ga-DOTATOC uptake relative to blood activity was invariably observed during the acute phase. SUVmax ratio exceeded 2.18 in all patients during the acute phase but also in 3/10 patients at 4-months, at a time when there were no more signs of active inflammation on CMR. A residual myocardial 68Ga-DOTATOC uptake was still observed on all gated-PET cine loops at 4-months. Conclusion These preliminary results suggest that 68Ga-DOTATOC ECG-triggered digital-PET may be as sensitive as CMR at detecting myocarditis during the acute phase and more sensitive at later stages. Supplementary Information The online version contains supplementary material available at 10.1007/s12350-022-03090-6. Key Words 68Ga-DOTATOC digital-PET myocarditis cardiac MRI somatostatin receptor issue-copyright-statement© American Society of Nuclear Cardiology 2023 ==== Body pmcIntroduction Myocarditis which evolves toward left ventricular dysfunction, heart failure, or arrhythmia is associated with a poor prognosis.1 Cardiac Magnetic Resonance (CMR) imaging has become the non-invasive gold-standard method for diagnosing myocarditis using the updated Lake-Louise diagnosis criteria.2 Unfortunately, this CMR-based diagnosis remains challenging in certain patients (i.e., those with irregular cardiac rhythms, claustrophobia, pacemakers, or severe obesity). CMR also lacks sensitivity for detecting subacute or chronic forms of myocarditis, characterized by cardiomyopathy-like or arrhythmia presentations.1 The Positron Emission Tomography (PET) imaging of somatostatin receptors may constitute an alternative diagnostic tool in this setting. Somatostatin receptors are overexpressed in lymphocytes, macrophages, and activated monocytes, the primary cell subsets involved in myocarditis.3 In contrast, somatostatin receptors are poorly expressed by cardiac cells under normal physiological conditions, and the observation of a significant cardiac uptake is rare on somatostatin-PET images recorded for conventional oncology indications.4 To date, only one single pilot study has provided evidence supporting a potential role of somatostatin-PET imaging for diagnosing myocarditis of suspected infectious origins.5 However, a high diagnostic potential was also previously shown for myocardial sarcoidosis6 and for myocarditis associated with immune check point inhibitor therapy.7 A recently published case report from our team has also provided supportive evidence for the potential of 68Ga-DOTATOC ECG-triggered digital-PET to delineate areas of myocarditis following COVID-19 vaccination.8 We postulated that this particular PET recording technique may be well adapted to this setting, given the capacity of digital-PET to image low-count structures9 and of ECG-triggered PET to prevent cardiac motion-related image blurring.10 The current study assesses the detection of acute myocarditis by ECG-triggered digital-PET imaging of somatostatin receptors (68Ga-DOTATOC PET), as compared to CMR imaging, the reference diagnostic method in this setting. Materials and methods This ongoing study, which aims to ultimately include a total of 30 patients, has to date enrolled 14 patients hospitalized for an acute myocarditis of a presumed infectious origin who fulfill the CMR 2018-updated Lake Louise criteria of acute myocarditis,2 with significant increases in plasma troponin-Ic levels and no other evident cardiac disease. Patients were referred for a first cardiac ECG-triggered 68Ga-DOTATOC PET/CT at ≤ 72 h after the initial CMR. Ten patients had a second ECG-triggered 68Ga-DOTATOC PET/CT on the day of the CMR follow-up, 4 months later. A venous blood sample was collected just before each 68Ga-DOTATOC PET/CT to determine C Reactive Protein (CRP) and Troponin Ic levels. 68Ga-DOTATOC PET/CT One hour after the injection of 2 MBq/kg of 68Ga-DOTATOC, the CT was recorded and immediately followed by a single bed position 15-minutes cardiac ECG-triggered PET on a digital hybrid PET/CT system (Vereos, Philips, Cleveland, Ohio), with the patient set in the prone position to reduce any respiratory motion-related cardiac displacements. Ungated-PET images were reconstructed with parameters favoring the contrast-to-noise ratio of small structures—i.e., 2-mm voxels, OSEM algorithm with 3 iterations and 3 subsets, a deconvolution of the point spread function and further corrections for scatter, random coincidences and attenuation.9 Gated-PET images were reconstructed with 8 interval-frames, 4-mm isotropic voxels, 2 iterations, 10 subsets, and further corrections for scatter, random coincidences, and attenuation. Ungated- and gated-PET images were analyzed with image scaling ranging from 0 to 3 Standardized Uptake Values (SUV). The uptake of 68Ga-Dotatoc was quantified on ungated-PET images according to a myocardial/blood ratio of maximal Standardized Uptake Values (SUVmax). SUVmax were determined from 2 cm diameter spherical volumes of interest (VOI) placed at a > 1 cm distance from liver activity (i) on the myocardial region showing the highest level of activity by visual analysis and (ii) on a blood region at the center of the right atrial cavity. The normal upper limit of this myocardial/blood SUVmax value had been defined as 2.18 according to the 95% confidence interval computed from 19 non-myocarditis patients consecutively selected on the basis of (i) age < 35 years (mean: 26 ± 6 years), so as to be in the age range of our myocarditis patients, (ii) no known cardiac history, and (iii) having undergone a whole-body 68Ga-DOTATOC PET/CT for an oncology indication with the Vereos camera. The non-myocarditis patients had 68Ga-DOTATOC PET for: (i) a suspected neuroendocrine tumor (n = 10) or (ii) the monitoring of a known somatostatin receptor-expressing tumor (n = 9). Two had a known paraganglioma, 1 was followed for a Von Hippel Lindau disease, 1 for a mesenchymal tumor and 5 had other types of neuroendocrine tumors. None of the non-myocarditis patients had a carcinoid syndrome, and 3 had a metastasis. CMR investigations CMR images were recorded on a 1.5T Avento or a 3T Prisma system (Siemens, Erlangen, Germany) to assess LV function and to detect signs of myocarditis:2 (i) on longitudinal (T1) and transversal (T2) relaxation maps recorded with Modified Look-Locker Inversion Recovery (MOLLI) and 2D TurboFlash sequences, respectively, and (ii) on contiguous delayed retention images covering the LV with a multi-slice phase-sensitive inversion recovery sequence, 10 to 15 minutes after the injection of 0.1 mmol/kg body weight of Dotarem® (GUERBET, France). Statistical analysis Qualitative variables are expressed as numbers and percentages, and quantitative variables as means ± SD. Wilcoxon and Mann–Whitney tests are used for paired and unpaired comparisons of quantitative variables and p values < 0.05 are considered to reflect significant differences. Results As detailed in Table 1, the first 14 sequentially enrolled patients with a myocarditis presumed to be of infectious origin included thirteen men and one woman. Their mean age was 25 ± 8 years (ranging from 18 to 49 years). All presented with elevated plasma troponin-Ic (mean troponin peak: 11.4 ± 12.3 ng/mL), associated with chest pain in 12 cases and with symptoms evocative of a gastrointestinal or respiratory tract infection in 5.Table 1 Main characteristics of the overall study population during the acute phase Age (years) 25 ± 8 Male 13 (93%) Peak troponin Ic in acute phase (ng/mL) 11.4 ± 12.3 LV ejection fraction at CMR (%) 49 ± 9 Abnormal (< 50%) 5 (36%) Day of the 1st PET/CT Delay time from peak Troponin (days) 4 ± 3 Troponin Ic (ng/mL) 2.1 ± 5.3 Abnormal (> 0.053 ng/mL) 9 (64%) C Reactive Protein (mg/mL) 12 ± 14 Myocardial SUV max 0.50 Myocardial/blood SUV max ratio 2.99 ± 0.49 Abnormal (> 2.18) 100% On the initial CMR, all myocarditis patients exhibited a characteristic sub-epicardial late gadolinium enhancement predominantly in the inferior and/or lateral walls, together with myocardial areas with increased T2 (> 54 ms on 1.5T Avento11 and > 47 ms on 3T Prisma12) and T1 (> 1140 ms on 1.5T Avento13 and > 1305 ms on 3T Prisma14), fulfilling the diagnostic criteria of acute myocarditis.2 The LV ejection fraction was < 50% in 5 cases (21% in one patient, who died before the 4-month follow-up; 40% in another one, 45% in two patients, and 49% in one patient). This contrasts with the 4-month follow-ups, where none of the patients had any abnormal T2 or ejection fractions (Table 2).Table 2 Evolution of the PET, CMR, and venous blood parameters between the acute phase and the 4-month follow-up in the 10 patients who had undergone the complete study protocol Acute phase At 4-months p values Troponin Ic (ng/mL) 0.648 ± 1.329 0.006 ± 0.003 0.005 C reactive protein (mg/mL) 10 ± 12 4 ± 8 0.575 CMR LV ejection fraction (%) 51 ± 6 54 ± 2 0.058 Aabnormal (< 50%) 2 (20%) 0 (0%) 0.500 Abnormal T1 10 (100%) 1 (10%) 0.004 Abnormal T2 10 (100%) 0 (0%) 0.002 Late gadolinium enhancement 10 (100%) 5 (50%) 0.063 PET/CT Myocardial/blood SUV max ratio 2.90 ± 0.52 1.97 ± 0.38 0.005 Abnormal (> 2.18) 10 (100%) 3 (30%) 0.016 As detailed in Tables 1 and 2, both troponin and CRP were still higher than normal in 9 patients on the day of the first PET. Three patients had elevated CRP values on the day of the second PET, whereas all troponin values were normal. PET imaging of acute phase The initial 68Ga-DOTATOC ECG-triggered PET was recorded at 4.4 ± 3.0 days from peak troponin and showed areas of increased myocardial uptake relative to blood activity in all myocarditis patients. These areas were consistently located in the inferior and/or lateral walls, and in most cases with multifocal or diffuse forms they were combined with a patchy distribution. Representative images of focal, multifocal, and diffuse forms are displayed in Figure 1. The gated-PET cine loops are available in an online supplement and allow the myocardial 68Ga-DOTATOC uptake to be visualized more easily, with better separation from the liver and less cardiac motion-related image blurring (see supplemental figure). The myocardium/blood SUVmax ratio was 2.99 ± 0.49 and was abnormal (> 2.18) in all myocarditis patients (Figure 2).Figure 1 Late contrast enhancement CMR images, and 68Ga-DOTATOC PET images represented as fused PET/CT slices and as maximal intensity projection (MIP) images, for representative myocarditis patients with a focal, multifocal, or diffuse myocardial increase in 68Ga-DOTATOC uptake during the acute phase. Image scaling ranges from 0 to 3 SUV. The myocardial areas with a CMR delayed retention and those with increased 68Ga-DOTATOC uptake are indicated with red arrows. Tracheobronchial nodes are indicated with orange arrows and esophagus and sternal bone marrow with green and blue arrows, respectively Figure 2 Box plot graph of the myocardial/blood SUVmax ratio in myocarditis patients during the acute phase (n = 14) and at 4-months (n = 10), relative to the non-myocarditis reference group (n = 19). The normal upper SUVmax limit of 2.18 is indicated with a red line PET imaging at the 4-month follow-up This second 68Ga-DOTATOC ECG-triggered PET was recorded 4.4 ± 0.2 months after the first in 10 of the 14 myocarditis patients and showed a marked decrease in the myocardium/blood SUVmax ratio (from 2.99 ± 0.49 to 1.97 ± 0.38, p = 0.005, see Figure 2 and Table 2). However, this SUVmax ratio remained higher, on average, than that computed in the control group (Figure 2), and it was still definitely abnormal (> 2.18) in 3 of the 10 patients (30%), at a time when there were no signs of persisting inflammation by CMR (i.e., when all myocardial T2 values had returned to normal). A residual myocardial 68Ga-DOTATOC uptake was still observed on the gated-PET images of all patients at 4-months, in the areas of high 68Ga-DOTATOC uptake during the acute phase. This point is best illustrated on the gated-PET cine loops in the supplemental figure. Discussion These preliminary results suggest that patients with acute myocarditis may be identified by increased myocardial 68Ga-DOTATOC uptake relative to blood activity and in most cases, with an ECG-triggered digital-PET pattern evocative of a patchy distribution of inflammatory cells predominantly in the lateral wall. This pattern is consistent with (i) the predominance of CMR abnormalities observed in the lateral wall of myocarditis patients, particularly for abnormalities associated with positive biopsy findings,1 and (ii) the heterogeneity reported between biopsy samples from different LV locations in this setting.1 In myocarditis, the density of inflammatory cells may be low, only a few dozen per mm2 on biopsy slices,15 and the density of somatostatin receptors is likely much lower than those of tissues commonly targeted by 68Ga-DOTATOC PET (i.e., neuro-endocrine tumors, sarcoidosis, or inflammatory nodes). This is the reason why the SUVmax from myocarditis areas was rather low here, 1.78 on average (Table 1). However, we used a fully digital-PET, whose performance is higher than that of current analog PET in low-count conditions (i.e., higher signal/noise ratio),9 and we made methodological choices expected to decrease the image blurring due to breathing (patient prone positioning) or cardiac motion (i.e., gated-PET with 8-frame per cardiac cycle, as already validated for the detection of infective endocarditis with FDG-PET10). It is currently not known whether more conventional PET cameras or protocols provide comparable results, even with higher injected doses. As illustrated in the supplemental file, the gated-PET images provide an easy identification of the mobile sites of myocardial 68Ga-DOTATOC uptake, even if the distal part of the inferior wall remains challenging to separate from liver activity in most cases. ECG-triggered FDG-PET images have previously been shown to be useful, when compared to conventional non-triggered FDG-PET images, for the detection of infective endocarditis, due to the decrease in cardiac motion-related image blurring.10 The gated-PET cine loops also provided evidence of areas of residual myocardial 68Ga-DOTATOC uptake in all of the 4-month follow-up investigations. These areas closely corresponded to those for which the 68Ga-DOTATOC uptake was high in the acute phase (see illustrations in the supplemental figure). At the present time, it is not known whether this residual uptake corresponds to a more or less active inflammation, to the normal healing process or both. Somatostatin receptors would not only be expressed on inflammatory cells (activated macrophage, lymphocytes and monocytes), but also on fibroblasts and fibrotic tissue.16 Also, the persistence at 4-months of a high myocardial/ blood SUVmax ratio in 3 of the 10 patients, at a time when there are no more signs of active inflammation according to the CMR (normal T2) and the blood biomarkers (normal troponin Ic), and its potential correlation with the evolution of LV function, will need to be further assessed. Initially 5 of our patients had a decreased LV ejection fraction. This decrease was mild to moderate (i.e., ranging from 40% to 49%) in 4 patients, and returned to normal in all 3 patients that had the 4-month follow-up. Peak troponin was not very high in these 5 patients (16 ± 16 ng/mL, on average), nor in the overall population (see Table 1), in accordance with previous observation that plasma troponin is not correlated with cardiac function in myocarditis.17 Cases of increased myocardial uptake by nuclear imaging of somatostatin receptors have been previously observed in various myocarditis and cardiac sarcoidosis,5-8 but also in subacute myocardial infarction18 and vulnerable coronary plaques.19 Increased myocardial uptake was also observed in patients who underwent 68Ga-DOTATOC PET for an oncology indication, in line with an older age, and with the presence of a history of cardiac disease and of cardiovascular risk factors.20 That is why we used a specific oncology reference patient population, who did not have any history of cardiac disease and who were as young as our myocarditis patients. However, the results of our ongoing study need to be confirmed using other reference populations and larger sample sizes. The PET imaging of somatostatin receptors is increasingly used worldwide, specifically using the theranostic approach (i.e., pre-therapeutic workup and treatment monitoring of neuro-endocrine tumors21). It is likely that the availability of these tracers will further improve in the future, and that their cost will be reduced, thereby favoring their use for inflammatory cardiac diseases. In conclusion, and although this remains to be confirmed on a larger scale, our preliminary results suggest that 68Ga-DOTATOC ECG-triggered digital-PET may be as sensitive as CMR for detecting myocarditis during the acute phase and more sensitive at later stages. These interim results were considered remarkable enough to be communicated, given the long time (2 years) required for inclusion of the initial 14 patients into the study and the potential usefulness of our preliminary observations for patients for whom a CMR diagnosis of acute myocarditis remains challenging (i.e., those with irregular cardiac rhythms, claustrophobia, pacemakers, severe obesity, and later myocarditis stages). The final results, expected to comprise data from 30 myocarditis patients, will not only allow to contribute more detail to these preliminary results but also determine whether differences in the evolution of LV function during follow-up may relate to concomitant changes in myocardial 68Ga-DOTATOC uptake. This uptake was unexpectedly variable and sometimes abnormally high at the 4-month follow-up, an observation that deserves a more specific evaluation. New knowledge gained 68Ga-DOTATOC ECG-triggered digital-PET may be as sensitive as CMR for detecting myocarditis during the acute phase and more sensitive at later stages, a property that may be particularly useful in patients for whom the CMR diagnosis of myocarditis remains challenging and when myocarditis is investigated at later stages. Electronic supplementary material Below is the link to the electronic supplementary material.Electronic supplementary material 1 (PPTX 5499 kb) Electronic supplementary material 2 (MP3 3900 kb) Supplemental Figure: Cine-loops corresponding to the fused CT/PET slices of the patients represented in Figure 1 (see Figure 1 legend), for both the acute phase and the 4-month follow-up. (MP4 7353 kb) Abbreviations CMR Cardiac magnetic resonance CRP C reactive protein CT Computed tomography FDG 18F-fluorodesoxyglucose LV Left ventricle OSEM Ordered subset expectation maximization PET Positron emission tomography SD Standard deviation SUV Standardized uptake value VOI Volume of interest Acknowledgements The authors wish to thank Dr Petra Neufing for critical review of the manuscript and the clinical research staff of Nancyclotep. Disclosures Caroline Boursier, Elodie Chevalier, Jeanne Varlot, Laura Filippetti, Olivier Huttin, Véronique Roch, Laetitia Imbert, Eliane Albuisson, Marine Claudin, Damien Mandry and Pierre-Yves Marie have no conflict of interest. Declarations Conflict of interest The authors declare that they have no conflict of interest. The sponsor was the Regional University Hospital Center (CHRU) of Nancy and this study was supported by grant from the French Ministry of Health (APJ 2015) and the authors wish to thank Advanced Accelerator Applications, a Novartis Company, for the free-of-charge providing of SOMAKIT TOC. The authors of this article have provided a PowerPoint file, available for download at SpringerLink, which summarises the contents of the paper and is free for re-use at meetings and presentations. Search for the article DOI on SpringerLink.com. The authors have also provided an audio summary of the article, which is available to download as ESM, or to listen to via the JNC/ASNC Podcast. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Tschöpe C Ammirati E Bozkurt B Caforio ALP Cooper LT Felix SB Myocarditis and inflammatory cardiomyopathy: current evidence and future directions Nat Rev Cardiol 2021 18 169 193 10.1038/s41569-020-00435-x 33046850 2. Ferreira VM Schulz-Menger J Holmvang G Kramer CM Carbone I Sechtem U Cardiovascular magnetic resonance in nonischemic myocardial inflammation: expert recommendations J Am Coll Cardiol 2018 72 3158 3176 10.1016/j.jacc.2018.09.072 30545455 3. Mues B Brisse B Zwadlo G Themann H Bender F Sorg C Phenotyping of macrophages with monoclonal antibodies in endomyocardial biopsies as a new approach to diagnosis of myocarditis Eur Heart J 1990 11 619 627 10.1093/oxfordjournals.eurheartj.a059767 2373096 4. Moyade P Vinjamuri S The heart matters: a review of incidental cardiac uptake on Ga-68 DOTA peptide PET-CT scans Nucl Med Commun 2019 40 1081 1085 10.1097/MNM.0000000000001064 31365503 5. Lapa C Reiter T Li X Werner RA Samnick S Jahns R Imaging of myocardial inflammation with somatostatin receptor based PET/CT—a comparison to cardiac MRI Int J Cardiol 2015 194 44 49 10.1016/j.ijcard.2015.05.073 26005805 6. Lapa C Reiter T Kircher M Schirbel A Werner RA Pelzer T Somatostatin receptor based PET/CT in patients with the suspicion of cardiac sarcoidosis: an initial comparison to cardiac MRI Oncotarget 2016 7 77807 77814 10.18632/oncotarget.12799 27780922 7. Boughdad S Latifyan S Fenwick C Bouchaab H Suffiotti M Moslehi JJ 68Ga-DOTATOC PET/CT to detect immune checkpoint inhibitor-related myocarditis J Immunother Cancer 2021 9 e003594 10.1136/jitc-2021-003594 34686542 8. Boursier C Chevalier E Filippetti L Imbert L Roch V Huttin O 68Ga-DOTATOC digital-PET imaging of inflammatory cell infiltrates in myocarditis following COVID-19 vaccination Eur J Nucl Med Mol Imaging 2022 49 1433 1434 10.1007/s00259-021-05609-4 34746968 9. Salvadori J Odille F Verger A Olivier P Karcher G Marie P-Y Head-to-head comparison between digital and analog PET of human and phantom images when optimized for maximizing the signal-to-noise ratio from small lesions EJNMMI Phys 2020 7 11 10.1186/s40658-020-0281-8 32086646 10. Boursier C Duval X Bourdon A Imbert L Mahida B Chevalier E ECG-gated cardiac FDG PET acquisitions significantly improve detectability of infective endocarditis JACC Cardiovasc Imaging 2020 13 2691 2693 10.1016/j.jcmg.2020.06.036 32828775 11. Haig C Carrick D Carberry J Mangion K Maznyczka A Wetherall K Current smoking and prognosis after acute ST-segment elevation myocardial infarction: new pathophysiological insights JACC Cardiovasc Imaging 2019 12 993 1003 10.1016/j.jcmg.2018.05.022 30031700 12. van Heeswijk RB Feliciano H Bongard C Bonanno G Coppo S Lauriers N Free-breathing 3 T magnetic resonance T2-mapping of the heart JACC Cardiovasc Imaging 2012 5 1231 1239 10.1016/j.jcmg.2012.06.010 23236973 13. Rosmini S Bulluck H Captur G Treibel TA Abdel-Gadir A Bhuva AN Myocardial native T1 and extracellular volume with healthy ageing and gender Eur Heart J Cardiovasc Imaging 2018 19 615 621 10.1093/ehjci/jey034 29617988 14. Wang X Joseph AA Kalentev O Merboldt K-D Voit D Roeloffs VB High-resolution myocardial T1 mapping using single-shot inversion recovery fast low-angle shot MRI with radial undersampling and iterative reconstruction Br J Radiol 2016 89 20160255 10.1259/bjr.20160255 27759423 15. Basso C Calabrese F Angelini A Carturan E Thiene G Classification and histological, immunohistochemical, and molecular diagnosis of inflammatory myocardial disease Heart Fail Rev 2013 18 673 681 10.1007/s10741-012-9355-6 23096264 16. Ambrosini V Zompatori M De Luca F Antonia D Allegri V Nanni C 68Ga-DOTANOC PET/CT allows somatostatin receptor imaging in idiopathic pulmonary fibrosis: preliminary results J Nucl Med 2010 51 1950 1955 10.2967/jnumed.110.079962 21078794 17. Butts RJ Boyle GJ Deshpande SR Gambetta K Knecht KR Prada-Ruiz CA Characteristics of clinically diagnosed pediatric myocarditis in a contemporary multi-center cohort Pediatr Cardiol 2017 38 1175 1182 10.1007/s00246-017-1638-1 28536746 18. Sazonova SI Syrkina AG Mochula OV Anashbaev ZZ Popov EV Ryabov VV Subacute myocardial infarction detected by technetium-99m-labeled somatostatin analog scintigraphy J Nucl Cardiol 2021 10.1007/s12350-021-02644-4 34046802 19. Anzola LK Rivera JN Ramirez JC Signore A Mut F Molecular imaging of vulnerable coronary plaque with radiolabeled somatostatin receptors (SSTR) J Clin Med 2021 10 5515 10.3390/jcm10235515 34884218 20. Itani M Haq A Amin M Mhlanga J Lenihan D Iravani A Myocardial uptake of 68Ga-DOTATATE: correlation with cardiac disease and risk factors Acta Radiol 2021 10.1177/02841851211054193 34713716 21. Fani M Mansi R Nicolas GP Wild D Radiolabeled somatostatin analogs-a continuously evolving class of radiopharmaceuticals Cancers (Basel) 2022 14 1172 10.3390/cancers14051172 35267479
PMC009xxxxxx/PMC9490704.txt	==== Front J Behav Med J Behav Med Journal of Behavioral Medicine 0160-7715 1573-3521 Springer US New York 36129586 355 10.1007/s10865-022-00355-w Article The prospective relations of substance use frequency to social distancing behaviors and intentions during the COVID-19 pandemic: the role of social distancing self-efficacy Scamaldo Kayla M. Tull Matthew T. Edmonds Keith A. Rose Jason P. http://orcid.org/0000-0002-2659-6784 Gratz Kim L. [email protected] grid.267337.4 0000 0001 2184 944X Department of Psychology, University of Toledo, Mail Stop 948, 2801 West Bancroft Street, 43606 Toledo, OH USA 21 9 2022 2023 46 3 483488 16 5 2022 29 7 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. To identify factors that increase risk for nonadherence to recommended health protective behaviors during pandemics, this study examined the prospective relations of substance use frequency to both adherence to social distancing recommendations and social distancing intentions during the COVID-19 pandemic, as well as the role of social distancing self-efficacy in these relations. A U.S. community sample of 377 adults completed a prospective online study, including an initial assessment between March 27 and April 5, 2020, and a follow-up assessment one-month later. Results revealed a significant direct relation of baseline substance use frequency to lower adherence to social distancing recommendations one-month later. Results also revealed significant indirect relations of greater substance use frequency to lower levels of both social distancing behaviors and intentions one-month later through lower social distancing self-efficacy. Results highlight the relevance of substance use and social distancing self-efficacy to lower adherence to social distancing during the COVID-19 pandemic. Keywords Substance use Social distancing COVID-19 Pandemic Self-efficacy Health behaviors http://dx.doi.org/10.13039/100012569 University of Toledo University of Toledo issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction To cope with the ongoing threat of infectious disease, it is common for governments to implement public health guidelines aimed at preventing or limiting community spread of a pathogen, many of which focus on health protective behaviors (e.g., social distancing, wearing masks). Although adherence to such guidelines is expected to have both societal and individual benefits, evidence suggests that sizable subsets of the population fail to adhere to recommended health protective behaviors during pandemics (often with deleterious consequences; Breitnauer 2020; Taylor & Asmundson, 2021). Thus, it is imperative to identify factors that relate to lower adherence to recommended health protective behaviors in the context of pandemics. The COVID-19 pandemic provides an ideal context for exploring this question. Specifically, the unprecedented worldwide spread and impact of COVID-19 prompted the implementation of extraordinary social distancing interventions and highlighted the public health importance of widespread adherence to these guidelines. Yet, given that individuals vary considerably in their adherence to social distancing recommendations (Coroiu et al., 2020), making the identification of factors that may increase risk for nonadherence to these recommendations of utmost importance. One factor that warrants attention in this regard is substance use. Consistent with evidence that substance use increases during periods of disease outbreaks (e.g., Lee et al., 2018), increases in substance use were observed during the early stages of the COVID-19 pandemic (Grossman et al., 2020; Taylor et al., 2021). In addition to the health risks associated with substance use in general, obtaining and using drugs in the context of a pandemic may confer unique risks for contracting and transmitting the virus by interfering with social distancing. For example, some substances can only be obtained through face-to-face interactions, necessitating social contact. Moreover, to the extent that substance use is motivated by desires to increase social affiliation (Votaw & Witkiewitz, 2021), individuals may be more willing to violate social distancing recommendations to meet these needs. Substance use may also reduce risk perceptions of disease (Maisto et al., 2002), thereby reducing motivation to adhere to social distancing recommendations. Finally, many substances (e.g., alcohol) have a disinhibiting effect that may interfere with decision making and increase the likelihood of noncompliance with social distancing and other health protective behaviors (Zvolensky et al., 2020). Notably, one factor that may account for reduced adherence to social distancing recommendations among individuals using substances during this pandemic is low self-efficacy for adhering to these recommendations. Defined as beliefs in one’s own ability to engage in a particular behavior, self-efficacy is theorized to play a key role in the initiation of and engagement in subsequent behaviors (Bandura, 1977) and has been identified as a primary factor influencing engagement in protective health behaviors within prominent models of health behavior (Janz & Becker, 1984; Rogers, 1975). Thus, consistent with these theories, perceptions of one’s ability to adhere to social distancing recommendations would be expected to influence both actual and intended engagement in these behaviors. With regard to the relation of substance use to self-efficacy for adhering to social distancing recommendations, studies have consistently shown that greater substance use frequency is associated with lower self-efficacy in general and for specific health protective behaviors (Kadden & Litt, 2011; Oei et al., 2007). Substance use would also be expected to decrease self-efficacy for adhering to social distancing recommendations in particular. Specifically, the need for face-to-face interactions to obtain certain substances, as well as heightened urges to use substances in social contexts (e.g., due to social affiliation motives), may decrease expectations that one is capable of adherence to social distancing. Likewise, repeated experiences with violating social distancing recommendations due to the disinhibiting effects of substances would also be expected to reduce self-efficacy for social distancing. Thus, this study examined the explanatory role of social distancing self-efficacy in the relation of substance use frequency to adherence to social distancing recommendations and social distancing intentions during the early stages of the COVID-19 pandemic. To this end, we examined the prospective relations of substance use frequency at the initial assessment (which coincided with the onset of most stay-at-home orders in the U.S.) to both adherence to social distancing recommendations one-month later and intentions to adhere to these recommendations in the following two weeks, as well as the role of social distancing self-efficacy in these relations. We hypothesized that baseline substance use frequency would be negatively associated with social distancing self-efficacy, adherence to social distancing recommendations, and social distancing intentions one-month later. In addition, we hypothesized that social distancing self-efficacy would account for significant variance in the relations of baseline substance use frequency to both social distancing behaviors and intentions one-month later. Method Participants Participants included a U.S. nationwide community sample of 377 adults who completed a prospective online study of health and coping in response to COVID-19 through an internet-based platform (Amazon’s Mechanical Turk; MTurk). Participants completed an initial assessment from March 27, 2020 through April 5, 2020 (corresponding to the onset of stay-at-home orders in most states), and a follow-up assessment approximately one month later between April 27, 2020 and May 21, 2020 (when strict stay-at-home orders began to ease and were replaced with social distancing orders and recommendations). The study was posted to MTurk via CloudResearch. For the present study, inclusion criteria consisted of: (1) U.S. resident, (2) ≥ 95% approval rating as an MTurk worker, (3) completion of ≥ 5,000 previous MTurk tasks, and (4) valid responses on questionnaires (assessed via multiple attention check items). Participants (52.3% female; 47.8% male) ranged in age from 20 to 74 years (M = 41.29, SD = 12.01) and represented 44 states in the U.S. Most participants identified as White (84.9%), followed by Black/African American (9.3%), Asian/Asian-American (4.3%), and Latinx (1.9%). At the time of the initial assessment, 10.9% of participants had graduated from high school or obtained a GED, 38.2% had completed some college or technical school, 41.4% had graduated from college, and 9.1% had advanced graduate/professional degrees. With regard to annual household income, 31.6% of participants reported an income of < $35,000, 31.6% reported an income of $35,000 to $64,999, and 36.9% reported an income of > $65,000. Measures Substance use frequency. The Drug Use Questionnaire (Hien & First, 1991) was used to assess baseline substance use frequency at the initial assessment. Participants indicated the frequency with which they used 12 substances (i.e., marijuana, alcohol, heroin, PCP, ecstasy, cocaine/crack, stimulants, sedatives, hallucinogens, inhalants, [misused] prescription drugs, and crystal meth) during the past month on a 5-point Likert-type scale (0 = Never; 4 = 4 or more times per week). The DUQ demonstrates good construct and convergent validity (Lejuez et al., 2007). Items were summed to create a total score of baseline substance use frequency (α = 0.76). Social distancing self-efficacy. Social distancing self-efficacy at one-month follow-up was assessed via a 3-item measure created for this study (derived from Brafford & Beck 1991). Participants were asked to rate three items assessing their perceived ability to follow U.S. social distancing recommendations on a 5-point Likert-type scale (1 = Not able at all; 5 = Completely able). Items were summed to create a total score of social distancing self-efficacy (α = 0.83). Adherence to social distancing recommendations. Adherence to social distancing recommendations at one-month follow-up was assessed using a 5-item self-report measure created for this study and derived from the theory of planned behavior (Ajzen, 1991). Participants were asked to report on engagement in recommended social distancing behaviors (e.g., avoiding large gatherings, staying 6 feet away from others) over the past two weeks on a 5-point Likert-type scale (1 = Never; 5 = Always). Items were summed to create an overall index of adherence to social distancing recommendations at follow-up (α = 0.88). Intentions to adhere to social distancing recommendations in the future. Intentions to adhere to social distancing recommendations in the two weeks after the one-month follow-up were assessed via a 5-item measure created for this study and derived from the theory of planned behavior (Ajzen, 1991). Participants were asked to report their intentions to engage in the aforementioned recommended social distancing behaviors over the next two weeks on a 5-point Likert-type scale (1 = Intend to never do the behavior; 5 = Intend to always do the behavior). Items were summed to create a total score representing social distancing intentions (α = 0.87). Clinical covariates. The Depression Anxiety Stress Scales-21 (DASS-21; Lovibond & Lovibond 1995) was used to assess symptoms of depression and anxiety at the initial assessment (αs ≥ 0.89 in this sample). Participants rate items on a 4-point Likert-type scale. The DASS-21 has adequate reliability and convergent and discriminant validity (Lovibond & Lovibond, 1995). Procedures All procedures received approval from the university’s Institutional Review Board. To ensure the study was not being completed by a bot, participants responded to a Completely Automatic Public Turing test to Tell Computers and Humans Apart prior to providing informed consent. Initial data were collected in blocks of nine participants at a time and all data, including attention check items and geolocations, were examined by researchers before compensation was provided. Participants who failed one or more attention check items were removed from the study (n = 53 of 553 completers). Those whose data were considered valid (based on attention check items and geolocations; N = 500) were compensated $3.00. One-month following completion of the initial assessment, participants were contacted via CloudResearch to complete the follow-up assessment. Of the 500 participants who completed the initial assessment, 77% (n = 386) completed the follow-up. Participants who failed two or more attention check items were removed from the study (n = 3); the rest were compensated $3.00. In addition, two participants were excluded for invalid data and four were excluded for extensive missing data on the measures of interest, resulting in a final sample size of 377. Results Preliminary analyses Descriptive statistics for and correlations among all variables of interest are presented in Table 1. The most frequently reported substances at the initial assessment were alcohol (53.8%), followed by marijuana (18%), prescription sedatives (8.2%), and prescription opioids (7.7%), with 44% of participants reporting regular use of alcohol and 13.3% reporting regular use of marijuana. To identify covariates for primary analyses, we examined associations of relevant demographic and clinical characteristics to the outcome variables (Table 1). Given significant associations of age, sex, and depression and anxiety symptoms to adherence to social distancing recommendations at follow-up, these variables were included as covariates in this model. Table 1 Correlations among and Descriptive Statistics for Primary Variables of Interest (N = 377) Variables 1 2 3 4 5 6 7 8 9 10 1. SU frequency - 2. SD self-efficacy − 0.22 - 3. SD adherence − 0.20 0.61 - 4. SD intentions − 0.03 0.15 0.14** - 5. Age − 0.10* 0.07 0.18 0.06 - 6. Sex − 0.09 0.10 0.19 − 0.02 0.17 - 7. Race/ethnicity 0.02 0.01 0.04 0.01 0.16 − 0.003 - 8. Income − 0.01 0.08 0.08 0.02 0.04 − 0.07 0.05 - 9. Depression 0.28 − 0.16 − 0.11* − 0.03 − 0.18** − 0.03 − 0.11* − 0.19 - 10. Anxiety 0.25 − 0.17 − 0.24 − 0.02 − 0.21 − 0.02 − 0.10 − 0.06 0.67 - Mean 2.65 13.23 22.80 19.36 41.29 0.52 0.85 4.50 7.90 4.77 Standard deviation 4.39 2.21 3.11 2.25 12.01 0.50 0.36 1.91 9.89 7.40 Note. SU Frequency = Baseline substance use frequency at the initial assessment; SD self-efficacy = social distancing self-efficacy; SD adherence = adherence to social distancing recommendations at one-month follow-up; SD intentions = intentions to adhere to social distancing recommendations in the two weeks after the one-month follow-up; Sex (0 = male assigned at birth; 1 = female assigned at birth); Race/ethnicity = racial/ethnic background (0 = racial/ethnic minority, 1 = non-minority); Income = annual household income (0 = < $50,000/year; 1 = ≥ $50,000/year); Depression = depression symptoms; Anxiety = anxiety symptoms. p < .05. *p < .01. Consistent with hypotheses, baseline substance use frequency was significantly negatively associated with social distancing self-efficacy and adherence to social distancing recommendations at the one-month follow-up; however, it was not significantly associated with intentions to adhere to social distancing recommendations at follow-up. Additionally, social distancing self-efficacy was significantly positively associated with both adherence to social distancing recommendations and intentions to adhere to social distancing recommendations. Primary analyses Next, we examined the indirect relations of baseline substance use frequency to both adherence to social distancing recommendations and social distancing intentions at one-month follow-up through social distancing self-efficacy using the PROCESS (version 3.0) macro for SPSS (Model 4; Hayes 2018). Indirect relations were evaluated using bias-corrected 95% confidence intervals based on 5,000 bootstrap samples. Providing partial support for study hypotheses, results revealed a significant direct relation between baseline substance use frequency and adherence to social distancing recommendations one month later (although not to social distancing intentions; see Table 2). Consistent with hypotheses, results revealed significant indirect relations of greater baseline substance use frequency to both lower adherence to social distancing recommendations and lower social distancing intentions at the one-month follow-up through lower social distancing self-efficacy (see Table 2). Table 2 Models Examining the Explanatory Role of Social Distancing Self-Efficacy in the Relations of Baseline Substance Use Frequency to Adherence to Social Distancing Recommendations and Social Distancing Intentions One-Month Later (N = 377) Independent Variable Explanatory Variable Dependent Variable Effect of IV on EV Effect of EV on DV Direct Effect Indirect Effect Total Effect a (p) SE b (p) SE c’ (p) SE a x b SE 95% CI c (p) SE SU frequency SDSE Adherence to social distancing − 0.171 (0.01) 0.033 0.571 (0.001) 0.072 − 0.044 (0.306) 0.03 − 0.098 0.042 − 0.184, − 0.019 − 0.142 (0.03) 0.046 Social distancing intentions − 0.22 (0.001) 0.032 0.145 (0.04) 0.071 − 0.0003 (0.997) 0.034 − 0.031 0.018 − 0.071, − 0.001 − 0.032 (0.589) 0.03 Note. IV = Independent variable. EV = Explanatory variable. DV = Dependent variable. SU Frequency = Baseline substance use frequency at the initial assessment; SDSE = social distancing self-efficacy; Adherence to social distancing = adherence to social distancing recommendations at one-month follow-up; Social distancing intentions = intentions to adhere to social distancing recommendations in the two weeks after the one-month follow-up Discussion To extend extant research on the factors associated with nonadherence to recommended health protective behaviors during pandemics, this study aimed to examine the prospective relations of substance use frequency to both adherence to social distancing recommendations and future social distancing intentions one-month later during the early stages of the COVID-19 pandemic in the U.S., as well as the explanatory role of social distancing self-efficacy in these relations. Consistent with study hypotheses, results revealed a significant direct relation of baseline substance use frequency to lower adherence to social distancing recommendations one-month later. This finding provides support for the premise that substance use may increase noncompliance with social distancing recommendations during the COVID-19 pandemic and is consistent with past research suggesting that frequent substance use is associated with poor adherence to protective behaviors in other contexts (Lasser et al., 2011; Liu et al., 2006). Notably, however, and contrary to predictions, substance use frequency did not have a significant direct relation to intentions to engage in social distancing behaviors in the weeks following the one-month follow-up. Thus, findings suggest that substance use may interfere with adherence to social distancing recommendations despite intentions to engage in such behaviors. This discrepant pattern of findings may capture the difficulties complying to social distancing recommendations posed by substance use, which may prompt engagement in risky behaviors that go against one’s self-interest for the purpose of obtaining or using substances. With regard to the theorized role of social distancing self-efficacy in the relations between substance use frequency and both adherence to social distancing and social distancing intentions, results provided support for study hypotheses, revealing significant indirect relations of greater substance use frequency to lower levels of both social distancing behaviors and intentions one-month later through lower social distancing self-efficacy. These findings are consistent with recent research highlighting the role of self-efficacy in both social distancing behaviors and intentions during the COVID-19 pandemic (Charles et al., 2020; Hamilton et al., 2020), and extend this research to a substance use context. Several limitations of this study warrant consideration. First, the generalizability of our findings to more severe substance use or the use of illicit substances like heroin or cocaine remains unclear. Another limitation is the exclusive reliance on self-report questionnaire data, which may be influenced by social desirability biases or recall difficulties. Future research should incorporate other assessment methods (e.g., ecological momentary assessment, timeline follow-back procedures) to further clarify the nature of the relation of substance use and social distancing during this pandemic. Further, although our use of a prospective design facilitates examination of the associations of baseline substance use frequency to both adherence to social distancing recommendations and social distancing intentions one-month later, we were not able to examine the interrelations of substance use, social distancing self-efficacy, and social distancing behaviors and intentions over time. Likewise, we cannot speak to the temporal relations among these factors and whether social distancing self-efficacy predicts social distancing behaviors or intentions. Research incorporating the repeated assessment of these factors over more extended time periods is needed to clarify the precise interrelations among these factors over time, including their likely reciprocal influences. Future research should also examine adherence to other health protective behaviors, such as mask-wearing and vaccinations. Beyond the risks associated with substance use in general, substance use in the context of a pandemic may be particularly risky insofar as it interferes with adherence to recommended health protective behaviors. Results of this study identify substance use as one factor that may negatively influence adherence to social distancing during the COVID-19 pandemic via lower social distancing self-efficacy. As the COVID-19 pandemic remains an ongoing public health crisis and evidence suggests the increased likelihood of future pandemics of this kind (Bernstein et al., 2022), identifying promising targets for interventions aimed at increasing engagement in health protective behaviors in the context of pandemics is critical. Results of this study highlight the potential utility of interventions targeting substance use and social distancing self-efficacy. Authors’ contributions All authors contributed to the study conception and design. Material preparation and data collection was performed by all authors. Data analysis was performed by Kayla Scamaldo, Kim Gratz, and Matthew Tull. The first draft of the manuscript was written by Kayla Scamaldo and Kim Gratz. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Funding This work was supported by funding from the Department of Psychology at the University of Toledo. Data Availability Data for this study is available upon reasonable request to Drs. Matthew T. Tull or Dr. Kim L. Gratz. Declarations Conflicts of interest/Competing interests The authors have no competing interests to declare that are relevant to the content of this article. Ethics approval All procedures performed in this study were in accordance with ethical standards of the institutional research committee and with the 19634 Helsinki Declaration and its later amendments or comparable ethical standards. The study was approved by the University of Toledo Institutional Review Board (300607-UT). Consent to participate Informed consent was obtained from all individual participants included in this study. Consent for publication Not applicable. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Ajzen I The theory of planned behavior Organizational Behavior and Human Decision Processes 1991 50 2 179 211 10.1016/0749-5978(91)90020-T Bandura A Self-efficacy: Toward a unifying theory of behavioral change Psychological Review 1977 84 2 191 215 10.1037/0033-295X.84.2.191 847061 Bernstein AS Ando AW Loch-Temzelides T Vale MM Li BV Li H Busch J Chapman CA Kinnaird M Nowak K Castro MC Zambrana-Torrelio C Ahumada JA Xiao L Roehrdanz P Kaufman L Hannah L Daszak P Pimm SL Dobson AP The costs and benefits of primary prevention of zoonotic pandemics Science Advances 2022 8 5 eabl4183 10.1126/sciadv.abl4183 35119921 Brafford LJ Beck KH Development and validation of a condom self-efficacy scale for college students Journal of American College Health 1991 39 5 219 225 10.1080/07448481.1991.9936238 1783705 Breitnauer, J. (2020). The Spanish Flu epidemic and its influence on history. Pen and Sword Charles, G., Jain, M., Caplan, Y., Kemp, H., Keisler, A., & Sgaier, S. K. (2020). Increasing uptake of social distancing during COVID-19: Behavioral drivers and barriers among US population segments. Available at SSRN 3602166 Coroiu, A., Moran, C., Campbell, T., & Geller, A. C. (2020). Barriers and facilitators of adherence to social distancing recommendations during COVID-19 among a large international sample of adults. PloS ONE, 15(10), e0239795 Grossman ER Benjamin-Neelon SE Sonnenschein S Alcohol consumption during the COVID-19 pandemic: A cross-sectional survey of US adults International Journal of Environmental Research and Public Health 2020 17 24 9189 10.3390/ijerph17249189 33316978 Hamilton K Smith SR Keech JJ Moyers SA Hagger MS Application of the health action process approach to social distancing behavior during COVID-19 Applied Psychology: Health and Well‐Being 2020 12 4 1244 1269 33006814 Hayes, A. F. (2018). Introduction to mediation, moderation, and conditional process analysis: A regression-based approach (2nd ed.). The Guilford Press Hien, D. A., & First, M. (1991). Drug use questionnaire. Unpublished scale, Columbia College of Physicians and Surgeons. New York State Psychiatric Institute Janz NK Becker MH The health belief model: A decade later Health Education Quarterly 1984 11 1 1 47 10.1177/109019818401100101 6392204 Kadden RM Litt MD The role of self-efficacy in the treatment of substance use disorders Addictive Behaviors 2011 36 12 1120 1126 10.1016/j.addbeh.2011.07.032 21849232 Lasser, K. E., Kim, T. W., Alford, D. P., Cabral, H., Saitz, R., & Samet, J. H. (2011). Is unhealthy substance use associated with failure to receive cancer screening and flu vaccination? A retrospective cross-sectional study. BMJ Open, 1(1), e000046 Lee SM Kang WS Cho AR Kim T Park JK Psychological impact of the 2015 MERS outbreak on hospital workers and quarantined hemodialysis patients Comprehensive Psychiatry 2018 87 123 127 10.1016/j.comppsych.2018.10.003 30343247 Lejuez CW Bornovalova MA Reynolds EK Daughters SB Curtin JJ Risk factors in the relationship between gender and crack/cocaine Experimental and Clinical Psychopharmacology 2007 15 2 165 175 10.1037/1064-1297.15.2.165 17469940 Liu H Longshore D Williams JK Rivkin I Loeb T Warda US Carmona J Wyatt G Substance abuse and medication adherence among HIV-positive women with histories of child sexual abuse AIDS and Behavior 2006 10 3 279 286 10.1007/s10461-005-9041-y 16501869 Lovibond, S. H., & Lovibond, P. F. (1995). Manual for the Depression Anxiety Stress Scales. The Psychology Foundation of Australia. Maisto SA Carey MP Carey KB Gordon CM The effects of alcohol and expectancies on risk perception and behavioral skills relevant to safer sex among heterosexual young adult women Journal of Studies on Alcohol 2002 63 4 476 485 10.15288/jsa.2002.63.476 12160107 Oei TP Hasking P Phillips L A comparison of general self-efficacy and drinking refusal self-efficacy in predicting drinking behavior The American Journal of Drug and Alcohol Abuse 2007 33 6 833 841 10.1080/00952990701653818 17994479 Rogers RW A protection motivation theory of fear appeals and attitude change The Journal of Psychology 1975 91 1 93 114 10.1080/00223980.1975.9915803 28136248 Taylor, S., & Asmundson, G. J. (2021). Negative attitudes about facemasks during the COVID-19 pandemic: The dual importance of perceived ineffectiveness and psychological reactance. PLoS ONE, 16(2), e0246317 Taylor S Paluszek MM Rachor GS McKay D Asmundson GJ Substance use and abuse, COVID-19-related distress, and disregard for social distancing: A network analysis Addictive Behaviors 2021 114 106754 10.1016/j.addbeh.2020.106754 33310690 Votaw VR Witkiewitz K Motives for substance use in daily life: A systematic review of studies using ecological momentary assessment Clinical Psychological Science 2021 9 4 535 562 10.1177/2167702620978614 34447615 Zvolensky, M. J., Garey, L., Rogers, A. H., Schmidt, N. B., Vujanovic, A. A., Storch, E. A., Buckner, J. D., Paulus, D. J., Alfano, C., & Smits, J. A. J. (2020). & O’Cleirigh, C. Psychological, addictive, and health behavior implications of the COVID-19 pandemic. Behaviour Research and Therapy, 134, 103715
PMC009xxxxxx/PMC9499988.txt	==== Front Genes Dis Genes Dis Genes & Diseases 2352-4820 2352-3042 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. S2352-3042(22)00250-1 10.1016/j.gendis.2022.09.005 Rapid Communication NSP16 promotes the expression of TMPRSS2 to enhance SARS-CoV-2 cell entry Han Tianyu abc1∗ Lei Jiapeng a1 Liu Yang d Wang Yanan ab Xun Wenze a Hu Qifan a Peng Qi a Zhang Wei ab∗∗ a Jiangxi Institute of Respiratory Disease, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, China b Jiangxi Clinical Research Center for Respiratory Diseases, Nanchang, Jiangxi 330006, China c Jiangxi Hospital of China-Japan Friendship Hospital, Nanchang, Jiangxi 330052, China d Department of Bacteriology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, China ∗ Corresponding author. ∗∗ Corresponding author. 1 These authors contributed equally to this work. 23 9 2022 5 2023 23 9 2022 10 3 723726 25 5 2022 11 9 2022 © 2022 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. 2022 Chongqing Medical University Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcSince the end of 2019, COVID-19 has caused worldwide pandemic. SARS-CoV-2, the culprit of this epidemic, binds to the host receptor Angiotensin converting enzyme 2 (ACE2) using spike (S) protein for cell entry. Recent studies showed that ACE2 expressed at a low level in the main target organs such as lung and bronchial tissues. How SARS-CoV-2 efficiently invades into the respiratory system or other organs with low levels of ACE2 is an urgent problem to be solved. Here, we discovered that NSP16 significantly promoted the invasion of SARS-CoV-2 pseudovirus. NSP16 could promote the formation of a STUB1-USP14 de-ubiquitination complex that regulated the ubiquitination and stability of transmembrane serine protease 2 (TMPRSS2). Inhibiting the function of this complex remarkably reduced the invasion ability of SARS-CoV-2 pseudovirus. Thus, our study demonstrates for the first time that NSPs of SARS-CoV-2 can also participate in viral invasion. To explore the effects of non-structural proteins (NSPs) on the entry of SARS-CoV-2 into human cells, we constructed all the NSP plasmids of SARS-CoV-2, except NSP3 and NSP11. We transfected these NSP plasmids into 293T cells and then SARS-CoV-2 pseudovirus was used to infect cells. As shown in Figure 1A and S1A, expression of NSP16 significantly enhanced the infection of the pseudovirus. Similar result was obtained in 293T cells stably expressing human ACE2 (293T-ACE2) (Fig. S1B). We next examined the effects of NSP16 on the expression of viral receptors and cofactors: ACE2, TMPRSS2, Tyrosine-protein kinase receptor UFO (AXL) and Cathepsin L (CTSL). Figure 1B and S1C showed that NSP16 significantly increased the protein expression of TMPRSS2. Treatment with the TMPRSS2 inhibitor-Bromhexine hydrochloride (BHH) significantly attenuated the infection of SARS-CoV-2 pseudovirus induced by NSP16 (Fig. S1D). We next explored the mechanism for NSP16 in up-regulating TMPRSS2. Previous study showed that 293T cells were TMPRSS2-negative.1 We first examined the expression of TMPRSS2 in 293T and other cell lines. Figure S2A and S2B showed that the expression of TMPRSS2 was much lower in 293T cells than that in Caco-2 cells. However, the mRNA and protein expression of TMPRSS2 in 293T cells were still detectable and comparable to that in bronchial epithelial cells (HBE). Overexpressing NSP16 did not affect the mRNA level of TMPRSS2 significantly (Fig. S2C). Then, protein stability of TMPRSS2 was examined. Cycloheximide (CHX) treatment led to significant decrease on TMPRSS2 expression at 12 h under physiological conditions, while the protein level of TMPRSS2 did not showed obvious decrease under the same condition when overexpressing NSP16 (Fig. 1C; Fig. S2D). Previous studies demonstrated that NSP16 together with NSP10 formed a complex and functioned as a 2′-O-methyltransferase.2 Figure S3A showed that NSP10 did not affect the increased expression of TMPRSS2 induced by NSP16. We wondered whether NSP16 regulated the ubiquitination of TMPRSS2. Overexpressing NSP16 did not influence the total ubiquitination of TMPRSS2 (Fig. S3B). However, the K48-linked ubiquitination of TMPRSS2 decreased remarkably when overexpressing NSP16, while the K63-linked ubiquitination did not significantly change (Fig. 1D; Fig. S3C). We confirmed this result by using mutant ubiquitin plamids (K63R and K48R). Figure S3D and S3E showed that overexpressing NSP16 decreased the ubiquitination of TMPRSS2 when transfected with ubiquitin-K63R, but not ubiquitin-K48R. On the contrary, the ubiquitination of TMPRSS2 increased when transfected with ubiquitin-K48R (Fig. S3E). As the total ubiquitination of TMPRSS2 did not change when overexpressing NSP16 (Fig. S3B), this result indicated that other lysine-linkage types of ubiquitination were also affected by NSP16 except K48 linkage. Interestingly, we found that NSP16 did not interact with TMPRSS2 (Fig. S4A). Then, mass spectrometry was used to explore the proteins interacted with NSP16. We discovered three E3 ligases (TRIM21, CUL2 and UBR5) and BAG2, a regulatory protein of the E3 ligase STUB1 (Fig. 1 E and Table S1).3 Immunoprecipitation showed that TRIM21 and STUB1 could interact with NSP16 (Figure 1F, S4B and S4C). Overexpression or knockdown of TRIM21 did not affect the expression of TMPRSS2 (Fig. S4D, E). However, overexpressing STUB1 significantly increased the expression of TMPRSS2 and knockdown of STUB1 decreased TMPRSS2 expression (Fig. S4F,G). Knocking down STUB1 could eliminate the up-regulation of TMPRSS2 induced by NSP16 (Fig. S4H), and STUB1 expression could stabilize TMPRSS2 protein (Fig. 1G).Figure 1 NSP16 promotes the expression of TMPRSS2 to enhance SARS-CoV-2 cell entry. (A) The NSPs of SARS-CoV-2 were transfected into 293T cells. After 24 h, the cells were seeded in a 24-well plate. After the cells adhered to the wells, the SARS-CoV-2 pseudovirus (GFP-SARS-CoV-2-S-Psv) was added and incubated for 24 h. The photographs were taken by fluorescence microscopy. (B) The NSPs of SARS-CoV-2 were transfected into 293T cells. After 48 h, the cells were lysed and Western blot was performed to detect the expression of the indicated proteins. (C) 293T cells were transfected with vector control or pCMV-FLAG-NSP16. After 48 h, the cells were treated with 25 μg/mL cycloheximide (CHX) for different times and the expression of the indicated proteins were detected by Western blot. (D) 293T cells were transfected with the indicated plasmids. After 48 h, immunoprecipitation was performed and the expressions of the indicated proteins were detected by Western blot. The K48-linked ubiquitination was detected using a K48-linkage specific polyubiquitin antibody. (E) The E3 ligases and the related proteins identified by mass spectrum were shown. (F) 293T cells were transfected with vector control or pCMV-FLAG-NSP16. After 48 h, immunoprecipitation was performed and the expressions of the indicated proteins were detected by Western blot. (G) 293T cells were transfected with vector control or pCMV6-FLAG-STUB1. After 48 h, the cells were treated with 25 μg/mL cycloheximide (CHX) for different times and the expression of the indicated proteins were detected by Western blot. (H) 293T cells were transfected with vector control or pCMV6-FLAG-STUB1. After 48 h, immunoprecipitation was performed and the expressions of the indicated proteins were detected by Western blot. (I) 293T cells were transfected with the indicated plasmids. After 48 h, immunoprecipitation was performed and the expressions of the indicated proteins were detected by Western blot. (J) 293T cells were transfected with vector control or pCMV6-FLAG-STUB1 or pEnCMV-FLAG-STUB1-H260Q. After 48 h, Western blot was performed to detect the expression of the indicated proteins. (K) 293T cells were transfected with vector control or pCMV-FLAG-USP14. After 48 h, immunoprecipitation was performed and the expressions of the indicated proteins were detected by Western blot. (L) 293T cells were transfected with the indicated plasmids. After 48 h, immunoprecipitation was performed and the expressions of the indicated proteins were detected by Western blot. (M) 293T cells were transfected with pCMV3-HA-TMPRSS2 alone or co-transfected with pCMV3-HA-TMPRSS2 and pCMV-FLAG-NSP16. After 48 h, immunoprecipitation was performed and Western blot was performed to detect the expression of the indicated proteins. (N) 293T cells were transfected with the indicated plasmids. After 48 h, 25 μg/mL CHX combined with or without 50 μM IU1 was added and treated cells for different times. The expressions of the indicated proteins were detected by Western blot. (O) 293T cells were transfected with the indicated plasmids and siRNAs. After 24 h, the cells were seeded in a 24-well plate. After the cells adhered to the wells, the SARS-CoV-2 pseudovirus was added and incubated for 24 h. The photographs were taken by fluorescence microscopy. (P) 293T cells were transfected with the vector or pCMV-FLAG-NSP16. After 24 h, the cells were seeded in a 24-well plate. After the cells adhered to the wells, the SARS-CoV-2 pseudovirus was added and treated with or without IU1 (50 μM) for 24 h. The photographs were taken by fluorescence microscopy. Figure 1 We next detected the interaction between STUB1 and TMPRSS2. Figure 1H and S4I showed that STUB1 and TMPRSS2 interacted with each other. Overexpressing STUB1 significantly reduced the total and K48-linked ubiquitination of TMPRSS2 (Fig. 1I; Fig. S4J), while the K63-linked ubiquitination was not affected (Fig. S4K). These results contradicted with the traditional function of STUB1 acting as an E3-ligase. As previously mentioned, BAG2 was a regulatory protein for the E3-ligase function of STUB1.3 However, overexpressing BAG2 did not influence the expression of TMPRSS2 (Fig. S4L). We also used a STUB1 mutant that lost its E3-ligase activity (STUB1-H260Q), and found that overexpressing STUB1-H260Q had similar effect on TMPRSS2 as with STUB1 wild-type (Fig. 1J). We further showed that NSP16 expression could increase the interaction between STUB1 and TMPRSS2 (Fig. S4M). These results indicated that STUB1 might affect ubiquitination of TMPRSS2 by regulating the function of a certain de-ubiquitinase. We next used UbiBrowser to find the potentially interacted de-ubiquitinases with STUB1 and USP14 was found. Figure 1K showed that USP14 interacted with STUB1. Overexpressing USP14 increased the expression and stability of TMPRSS2 (Fig. S5A, B). Figure 1L and S5C showed that overexpressing USP14 decreased the total and K48-linked ubiquitination of TMPRSS2, but not the K63-linked ubiquitination (Fig. S5D). Knocking down STUB1 eliminated the de-ubiquitination of TMPRSS2 mediated by USP14 (Fig. S5E). We further demonstrated that NSP16 facilitated the formation of a new de-ubiquitination complex: the STUB1-USP14 complex (Fig. 1M). The protein stability of TMPRSS2 was strictly regulated by this de-ubiquitination complex. Blocking the activity of USP14 using specific inhibitor-IU1 inhibited the regulatory ability of NSP16 and STUB1 on TMPRSS2 protein stability (Fig. 1N). Also, knockdown of STUB1 could alleviate the enhanced protein stability of TMPRSS2 induced by NSP16 or STUB1 (Fig. S5F). We next examined the effects of the STUB1-USP14 complex on the infection of SARS-CoV-2. Overexpressing NSP16 or USP14 or STUB1 all increased the infection of SARS-CoV-2 pseudovirus and knocking down STUB1 significantly attenuated NSP16-induced viral infection (Fig. 1O; Fig. S6A). Inhibiting the activity of USP14 using IU1 also greatly weakened the infection of SARS-CoV-2 pseudovirus induced by NSP16 (Fig. 1P; Fig. S6B). Thus, our study demonstrated for the first time that NSPs of SARS-CoV-2 participated in viral invasion (Fig. S7). One of the limitation of this study is that we only used the pseudovirus system, live viruses should be used to further confirm these results. Taken together, our study provides a reasonable explanation for SARS-CoV-2 efficiently entry into host organs with low expression of ACE2, such as lung and bronchus. Author contributions T. H. and W. Z. conceived and designed the study. T. H., J. L., Y. W., W. X., Q. H., Y. L., Q. P. performed the experiments. T. H. and J. L. analyzed data. T. H. and W. Z. wrote the manuscript. This manuscript was approved by all authors. Conflict of interests The authors declare no conflict of interests. Appendix A Supplementary data The following are the Supplementary data to this article:Multimedia component 1 Multimedia component 1 Multimedia component 2 Multimedia component 2 Multimedia component 3 Multimedia component 3 Multimedia component 4 Multimedia component 4 Multimedia component 5 Multimedia component 5 Multimedia component 6 Multimedia component 6 Multimedia component 7 Multimedia component 7 Multimedia component 8 Multimedia component 8 Multimedia component 9 Multimedia component 9 Funding This work was supported by Clinical Research Cultivation Project of First Affiliated Hospital of 10.13039/501100004637 Nanchang University (China) (No. YFYLCYJPY202001). Peer review under responsibility of Chongqing Medical University. Appendix A Supplementary data to this article can be found online at https://doi.org/10.1016/j.gendis.2022.09.005. ==== Refs References 1 Bertram S. Glowacka I. Blazejewska P. TMPRSS2 and TMPRSS4 facilitate trypsin-independent spread of influenza virus in Caco-2 cells J Virol 84 19 2010 10016 10025 20631123 2 Rosas-Lemus M. Minasov G. Shuvalova L. The crystal structure of nsp10-nsp16 heterodimer from SARS-CoV-2 in complex with S-adenosylmethionine bioRxiv 2020 2020.04.17.047498 3 Qin L. Guo J. Zheng Q. BAG2 structure, function and involvement in disease Cell Mol Biol Lett 21 2016 18 28536620
PMC009xxxxxx/PMC9510967.txt	==== Front spihe IHE Industry and Higher Education 0950-4222 2043-6858 SAGE Publications Sage UK: London, England 10.1177_09504222221126420 10.1177/09504222221126420 Articles Graduate employability concerns amidst a crisis: Student perspectives from Singapore on COVID-19 https://orcid.org/0000-0002-1396-762X Tan Eunice Mwagwabi Florence Lim Tania Lim Amy 5673 Murdoch University , Australia Eunice Tan, Singapore Discipline Lead (Tourism & Events), College of Arts, Business, Law and Social Sciences, Murdoch University (Singapore), 390 Havelock Road, #03-01 King’s Centre, Singapore 169662, Singapore. Email: [email protected] 23 9 2022 6 2023 23 9 2022 37 3 370383 © The Author(s) 2022 2022 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. With the ongoing challenges of COVID-19, global economies continue to face uncertainties, widespread workforce volatility and employment challenges. During a sustained crisis such as the COVID-19 pandemic, university students’ self-perceptions about their employability and future career choices in their chosen industry sectors may be affected. Therefore, this study investigates graduate employability concerns and the perceptions of undergraduate students regarding employment prospects and future job security confidence in their disciplines’ industry sectors in light of this global crisis. Through the employment of a mixed methods design, the study investigates the perceptions of graduating students from three disciplines in Singapore: Tourism, Communications and Information Technology. The findings indicate that COVID-19 had a positive impact on perceptions of jobs that could be performed from home and those in essential services. Concurrently, there were notable variances in the students’ perceptions regarding career prospects and job security confidence across the three disciplines with regard to the impact of the crisis on their industry sectors in general and themselves individually. Career prospects COVID-19 crisis employment shocks graduate employability job confidence job security typesetterts10 ==== Body pmcThe COVID-19 pandemic has dramatically affected all economies and industry sectors. It is estimated that global GDP contracted by 3.5% in 2020, with 300 million full-time jobs lost (Padhan and Prabheesh, 2021). Economic recovery is expected to be erratic until 2023, due to continued global disruptions in travel and the economy and country-specific restrictions (World Bank, 2022). In particular, small internationally connected countries like Singapore felt the negative effects of COVID-19 considerably; Singapore’s GDP contracted by 5.4% in 2020, although it regained 3%–5% in 2021 (Ministry of Trade and Industry, Singapore, 2021a, 2021b). A sustained crisis such as the global pandemic represents a potential career shock for university students, impacting their career aspirations and self-perceptions about their employability and job prospects within their chosen industry sectors (Akkermans et al., 2020; Capone et al., 2021; Pedersen et al., 2020). Shobha and Johnson (2021) posit that the COVID-19 pandemic has radically altered the concepts of employability and has transformed business models within a reimagined workforce. However, the overall impacts of COVID-19 at the sectoral level remain uneven. Despite generalised acknowledgements about the employment shocks from this pandemic, there has been divergence concerning the distribution of effects on different industry sectors and occupations. Early COVID-19 related labour-market data (Akkermans et al., 2020; Baert et al., 2020; Dingel and Neiman, 2020; del Rio-Chanona et al., 2020; Garrote Sanchez et al., 2020; Montenovo et al., 2020; Padhan and Prabheesh, 2021) highlight differences in future job security impacts and employability outcomes across industry sectors and occupations. For example, in Singapore consumer-facing sectors (such as the hospitality, tourism and aviation industries) were severely affected, while outward-facing sectors, like the info-communication and media industries, fared better. Concurrently, there has been increased demand for information technology and digital media services, coupled by a strong governmental push for digital transformation efforts (Ministry of Trade and Industry, Singapore, 2021a, 2021b). Considering these divergences, this study posits that university students’ self-perceptions of graduate employability could be influenced by confidence in industry sectors and occupations, as well as more general concerns about the pandemic and ongoing global economic conditions (Capone et al., 2021). Whilst this study is focused on students’ perceptions during COVID-19, the findings contribute to the development of resilience-based interventions, organised responses, recovery and rebuilding during future pandemics, unexpected crises and shocks (Couclelis, 2020; Nandy et al., 2021). Anticipating post-pandemic recovery in numerous economies and sectors, commentaries from academia and industry caution that the ramifications of this global crisis and the pervasiveness of pandemic-induced habits will linger for years, if not decades, to come (Hall, 2021; Kolata, 2021; Najam, 2021). In fact, Kolata (2021) posits that, based on observations of past pandemics, COVID-19 will be an ‘era’, rather than an episodic crisis that fades. Therefore, the aim of this study is to investigate university students’ self-perspectives on future job security confidence, contextualised from employability concerns during a time of crisis. As Capone et al. (2021) observe, university students are experiencing high levels of uncertainty about their employability and career prospects during this sustained crisis. Specifically, the study evaluates these employability concerns between different industry sectors in the context of Singapore. Therefore, undergraduate students from three distinct academic disciplines in Singapore are investigated: (1) Tourism, (2) Communications and (3) Information Technology (IT). This is significant since there is an anticipated divergence of impacts from the crisis among industry sectors (including academic disciplines and programmes of study) in Singapore. Literature review Graduate employability and employment prospects This section reviews some key factors that affect graduate employability and employment prospects in higher education. Broadly, graduate employability is defined as the potential for graduates to gain initial employment, maintain employment and obtain new employment if required, based on available alternatives in the labour market (Jackson, 2014; Pool and Sewell, 2007; Saher and Hussain Ch, 2019; Tomlinson, 2012). This perspective on graduate employment and the dimensions for developing ‘career-ready graduates’ assess the prime qualities that make one employable, able to retain employment and able to transfer learned skills to the workplace. Indeed, the issue of graduate employability is of continuing concern to industry and institutional policymakers, especially as the relationship between higher education, industry and the labour market has fundamentally shifted with increased job uncertainties and competition (Kornelakis and Petrakaki, 2020; Tomlinson, 2012). While macro policies and market changes impact students’ perceived employability in different industries, extant studies on the graduate employability discourse (e.g. Capone et al., 2021; Matsouka and Mihail, 2016; O’Leary, 2015) point to the need to address mismatched expectations between fresh graduates and hiring managers, and to embed employability-related support into higher education. Understanding graduates’ self-perceived employability within and between academic disciplines and industry sectors is important in the graduate employability discourse (O’Leary, 2015; Saher and Hussain Ch, 2019). Self-perceptions about graduate employability are contextualised in terms of how individuals may perceive their own career prospects, aspirations and capacity to successfully compete in the labour market (Jackson and Tomlinson, 2020). However, it is important to acknowledge the complexity of the employability construct and its constituent dimensions beyond just employment attributes. Tomlinson (2012) acknowledges the contested interpretations of graduate employability and increased criticism of dominant discourses on graduate employability in higher education and the labour market that are focused primarily on the economic and employment perspectives. Relatedly, recent contributions to the employability discourse (e.g. Matsouka and Mihail, 2016; O’Leary, 2015; Shobha and Johnson, 2021) highlight the merits of acknowledging individual personal attributes and wider societal factors within a multifaceted construct of employability. Thus, employability-related discourses should examine thematic dimensions beyond employment and workforce outcomes to include considerations such as occupational aspirations, individual identity, contributions to the community and/or societal change. Wider socio-cultural and individual factors can also frame graduating students’ self-perceptions regarding their future job and career prospects. The extant employability discourse posits a shift from traditional institutional-, state- or employer-centric employability agendas towards a more self-determining concept of employability, wherein future employability is dependent not on the state but on individual factors and responsibility (Saher and Hussain Ch, 2019). Today’s graduates are more trained, confident and self-defined with a diversity of skills. However, they face more competition and volatile job markets while seeking employment (Hite and McDonald, 2020). Further, graduates’ self-belief and future job market identity may be tied to personal dimensions such as social background, gender and ethnicity (Cotton et al., 2021; Tomlinson, 2012). Consequently, the employability discourse must consider the multifaceted interactions between internal (individual factors) and external (workforce environmental factors) dimensions, which may have implications for graduates’ employability outcomes, job security confidence and employment prospects. This may be particularly evident during times of crisis and turbulent market conditions such as the present pandemic. Impact of crises on graduate job security confidence and employment prospects A sustained crisis such as COVID-19 can considerably impact graduate employability outcomes and can lead to major workforce industry adjustments due to the significance and extent of the adverse employment conditions. Such adjustments amid a volatile and uncertain labour market may exacerbate graduates’ employability concerns and career prospects, as well as their ability to pursue opportunities within aligned career roles. Consequently, the future of careers, workforce and workplaces may trigger diverse challenges and opportunities for graduates, depending on individual, contextual and occupational factors (Hite and McDonald, 2020; Pedersen et al., 2020). In this context, Shobha and Johnson (2021) posit that the concept of employability in a post-crisis scenario requires a framework in which (1) internal and external factors and (2) individual and collective environments are incorporated. Graduates’ expectations and self-perceptions of employability are multidimensional and vary between and within different industry sectors and occupations (Coates et al., 2020; Rothwell et al., 2008). Increasingly, graduates are becoming conscious that academic qualifications alone may not be adequate to secure a suitable job in their chosen industry sector (Capone et al., 2021). In a turbulent market, the ability to develop the necessary employability skills, personal characteristics and career competencies can benefit both graduates and industry (Matsouka and Mihail, 2016). Graduate employability is also affected by perceived status differences among top jobs and sectoral demand for qualifications (Dingel and Neiman, 2020), and these may be tied to sector-specific differences in employability outcomes and differences in the types of jobs and occupations (Baert et al., 2020; del Rio-Chanona et al., 2020; Montenovo et al., 2020). In the context of employability concerns regarding the increased vulnerability of fresh graduates to a volatile job market during a crisis (Capone et al., 2021), a review of extant literature investigating graduates’ perceptions of employability and employment prospects suggests a multifaceted construct that can be broadly clustered into five key dimensions: (1) self-perceptions and self-beliefs, (2) students’ sense of future orientation, (3) psycho-social constructs of employability, (4) policy responses and risk perceptions among graduates and (5) institutional brand and vocational status (Coates et al., 2020; Dingel and Neiman, 2020; del Rio-Chanona et al., 2020; Garrote Sanchez et al., 2020; Montenovo et al., 2020; Kornelakis and Petrakaki, 2020; Rothwell et al., 2009; Tomlinson, 2012). Table 1 summarises these five dimensions impacting graduate employability and employment prospects during a sustained crisis such as COVID-19.Table 1. Dimensions impacting graduate employability. Influencing dimension Focus and/or implications based on Self-perceived employability and self-belief An individual’s self-perceived capacity to gain sustained employment befitting their level of qualification Students’ sense of future orientation An individual’s adaptability and flexibility towards changing occupational criteria or labour market challenges Psycho-social constructs of employability The amalgamation of person-centred constructs concerning one’s career identity, personal adaptableness, career motivation and social, human, and intellectual capital Policy responses and graduates’ risk perceptions Policy responses from institutions, governments and regulatory bodies, and graduates’ risk perceptions regarding successful transition to and alignment with labour market challenges Institutional brand and vocational status The ‘legitimatisation of credentials’ due to perceived status differences and impact(s) on employability, including: (1) reputation or brand image of institution attended; and (2) perceived sectoral demand for qualifications from particular academic disciplines/vocational areas The global pandemic has affected market economies, leading to adverse employment conditions and job losses associated with pandemic-related lockdowns, decreased physical and social mobility and reduced demand in the consumption of goods and services (Padhan and Prabheesh, 2021; Pedersen et al., 2020). It is likely, in such a context, that jobs that can be performed at home and are considered to be essential services will encounter different employability impacts. According to Dingel and Neiman (2020), by industry sector the top five jobs that can be performed at home are: (1) educational services, (2) professional, scientific and technical services, (3) enterprise management, (4) finance and insurance and (5) information. And the bottom five are: (1) transportation and warehousing, (2) construction, (3) retail trade, (4) agriculture, forestry, and fishing and (5) accommodation and food services. Correspondingly, employment losses may be larger in jobs that involve face-to-face contact and smaller in jobs that can be performed remotely. At the same time, work continues in essential industries. Another impacting factor that may affect graduates’ perceived job security confidence is anticipated job risk. In the context of the pandemic, such perceived risks may correspond to imposed regulatory or policy responses (Garrote Sanchez et al., 2020; Leach, 2017). For instance, COVID-19 policy responses such as mandated social distancing measures and lockdowns for affected sectors (Coates et al., 2020) mean that occupations that can feasibly be performed at home, or that are flexible in their relocation, are less likely to suffer from job losses; on the contrary they may potentially offer opportunities for earning higher wages. Conversely, occupations that require closer physical proximity or face-to-face interaction tend to be at greater job loss risks, except where these are related to the health industry, social assistance and public administration. On the labour supply side, the transmission mechanisms of COVID-19 also raise the health risks of work tasks that require face-to-face contact. Such heterogeneity and imbalance in supply and demand shocks could exacerbate the disparities in an already unequal job labour market and society. Graduates’ self-perceived employability concerns relating to job security confidence can have implications for career choices. When assessing the impacts of events such as the COVID-19 pandemic on graduating students’ career choices, two key thematic dimensions emerge: (1) the degree of job vulnerability and (2) susceptibility to career shocks and the degree of resilience (Garrote Sanchez et al., 2020; Gupta, 2020; Hite and McDonald, 2020; Nandy et al., 2021). While job vulnerability has multiple aspects, vulnerable jobs often relate to tasks, characteristics or sectors associated with non-standard work and with greater risk exposure to economic shocks and labour market disturbances (del Rio-Chanona et al., 2020; Honorati et al., 2020; Montenovo et al., 2020). Besides perceived job vulnerability, graduates’ career choices may also be impacted by the apparent susceptibility to career shocks. As Akkermans et al. (2020) suggest, career shocks have varying attributes that may impose contrasting employability consequences, positive or negative, on different careers and individuals. Career shocks refer to the frequency, intensity, controllability and duration of potentially disruptive and extraordinary events; particularly those triggered by circumstances outside an individual’s control and which may directly impact on their career development and future prospects (Akkermans et al., 2020; Hite and McDonald, 2020). In this context, an individual’s preparedness and ability to recover and adapt to crisis events is consequential. Correspondingly, an individual’s ability to weather labour market upheavals in their career depends on their degree of resilience, reflexivity and ideals of self-identity in the face of challenges (Leach, 2017). From a graduate employability perspective, an individual’s degree of resilience also affects their employability, workplace readiness and transition to the job market (Nandy et al., 2021). These COVID-related challenges and employability concerns are therefore the focus of the study and are discussed below. Conceptual framework and research questions Development of a contextualised, conceptual framework may deepen understanding of how COVID-related graduate employability concerns may impact students’ career aspirations, employment prospects and future job security in Singapore and, more generally, during a sustained crisis. Considering the potential heterogeneity in COVID-related challenges and employability outcomes across different industry sectors, an investigation of university students’ self-perceptions across disciplines is valuable. Therefore, the research questions for this study are:• RQ1: How do perceived prospects in jobs that can be performed from home and those in essential services impact graduating students’ future job security confidence? • RQ2: Does job security confidence significantly differ by programme type? • RQ3: Would their perceptions influence graduating students’ perceived career prospects and future job security confidence in each of the three industry sectors? The key research dimensions of the study discussed in this literature review and its associated research questions are illustrated in Figure 1, which shows the conceptual framework. As illustrated in the figure, to precisely assess the implications of a sustained crisis such as COVID-19, this study investigates graduate employability within the key dimensions of job security confidence and employment (job and career) prospects. Further, it investigates whether perceived job and career prospects are influenced by jobs that can be performed from home and those in essential services (RQ1). Finally, this study posits that there may be variances in the impacts of COVID-19 on graduating students’ career choices and perceived job security confidence between disciplines and industry sectors (RQ2 and RQ3), due to the intersection of the above multidimensional aspects of graduate employability.Figure 1. Conceptual framework of employability concerns during a crisis. Methodology This is an exploratory study, adopting a mixed-methods, cross-sectional design that utilises web survey quantitative measures, augmented with qualitative data to examine these pandemic-induced employability concerns. As Castro et al. (2010) suggest, the adoption of an integrative mixed-methods design enables rigorous and integrative analysis of quantitative numeric data with qualitative textual evidence and augments the richness of its interpretation. Participants Participants for the survey were recruited using convenience sampling based on their status as students from the classes of 2020–2022 graduating during this pandemic and who were currently undertaking programmes in the disciplines of: (i) Tourism, Hospitality and Events, (ii) Information Technology, and (iii) Media and Communications, at Murdoch University (Singapore). These selection criteria were articulated to potential respondents in the information statement of the survey instrument, which was conducted online via QualtricsXM between July 2020 and June 2021. Following Rothwell et al. (2009), the sample size estimation required to detect a relationship between the students’ self-perceived employability scale was made assuming a medium effect size (given the relatively untested nature of the dimensions evaluated) with a power of 0.80 (α = 0.05), positing a preferred minimum sample size of 102. The total number of valid completions was 175, a valid response rate of 25.4% (687 email invitations were distributed). Given that online surveys yield lower response rates, ranging from as low as 7% to an average of 34% (Shih and Fan, 2008), the response rate for this study is acceptable. Among the 175 participants, nine students were under 21 years old, 122 were between 21 and 34, eight were between 35 and 44 and one student was between 45 and 54 (35 participants chose not to respond to this question). With regard to the question on gender, 67 stated that they were female, 66 that they were male and 42 chose not to specify male or female. With regard to graduation, 24 participants reported their graduating year as 2020, 131 said 2021, and 20 said 2022. Procedure and materials On providing informed consent, participants responded to a series of questions assessing employability and job prospects. To ensure the validity and reliability of the measurement items in the questionnaire developed, employability measures based on previously validated items were adapted in the context of the study. These included: (1) Rothwell et al. (2008) for the measurement of self-perceived employability and job prospects by undergraduate students and (2) Baert et al. (2020) and Jackson (2014) for students’ perceptions regarding the impact of a crisis on career prospects and job attainment/retention. Further, to address the research questions posited in RQs 1–3, survey items were adapted from Dingel and Neiman (2020), measuring graduating students’ perceived prospects in jobs that could be performed from home, perceived prospects in essential services and future job security confidence levels. These items were measured on a 7-point Likert scale from 1 = strongly disagree to 7 = strongly agree. Analytical strategy To determine whether the students enrolled in Tourism, Communications and IT differed significantly in their perceptions regarding job and career prospects and job security confidence, ANOVA analyses were conducted. Additionally, to examine whether such perceptions would influence job security confidence, a regression analysis was conducted. Prior to conducting these parametric tests, the assumption of normality was assessed. Values for skewness and kurtosis for perceived job prospects for jobs performed from home (Table 2), job prospects for essential services (Table 3), and job security confidence (Table 4) were between −2 and +2 across the different disciplines, which were acceptable standards for a normal distribution (George and Mallery, 2010). Tests of the homogeneity of variances also revealed that the assumption of homogeneity of variance had not been violated for job prospects from home, essential services and job security confidence (ps > 0.06). Univariate outliers were identified for perceived job prospects for jobs performed from home (N = 6) and perceived job prospects for essential services (N = 1). ANOVA analyses were conducted with and without these univariate outliers. Assumptions of normality, linearity and homoscedasticity of residuals, and multicollinearity between predictors were examined and no assumption violations were noted. Nine multivariate outliers were observed; subsequent linear regression analyses were conducted with and without the multivariate outliers.Table 2. “I believe that COVID-19 will have a positive impact on jobs that can be performed from home.” Tourism, hospitality and events Media and communications Information technology Mean 5.05 5.65 5.39 SD 1.31 1.23 1.29 Skew −0.85 −1.07 −0.78 Kurtosis 0.15 0.91 0.65 Table 3. “I believe that COVID-19 will have a positive impact on jobs that are considered to be essential services.” Tourism, hospitality and events Media and communications Information technology Mean 5.54 5.50 5.17 SD. 1.29 1.47 1.47 Skew −0.79 −0.98 −1.01 Kurtosis −0.07 0.56 1.03 Table 4. Social confidence. Tourism, hospitality and events Media and communications Information technology Mean 4.51 4.38 4.77 SD. 1.28 1.57 1.28 Skew −0.004 −0.12 −0.12 Kurtosis −0.50 −1.10 −0.33 In terms of qualitative analysis, the textual narratives collected from the open-ended questions were reviewed and organised during the open coding process, followed by preliminary clustering of thematic categories that emerged from the data into emergent themes, labels and node categories. Microsoft Excel and QSR NVivo12 were used for the open coding, axial and selective coding processes. The qualitative narratives analysed enrich and contextualise the quantitative data collected, providing support for multidimensional thematic analysis (Castro et al., 2010). The resultant data analysis is discussed below. Results Impact of COVID-19 on perceived job prospects across industry sectors This first section of the analysis relates to the results for RQ1, which assesses students’ perceptions of the impact of COVID-19 on prospects for jobs that can be performed from home, and jobs considered as essential services. Students responded to two items on a 7-point Likert scale: “I believe that COVID-19 will have a positive impact on jobs that can be performed from home”, and “I believe that COVID-19 will have a positive impact on jobs that are considered to be essential services”. Higher scores reflect a stronger belief that the COVID-19 crisis had a positive impact on jobs that could be performed from home (M = 5.35, SD = 1.30) and on jobs considered as essential services (M = 5.38, SD = 1.42). One-way ANOVAs were conducted to examine differences in perceived job prospects in (1) jobs that could be performed from home and (2) jobs in essential services across sectors. The results show that there were no significant differences for prospects regarding jobs that could be performed from home (F (2, 172) = 2.82, p = 0.06) and those that were essential services (F (2, 172) = 1.30, p = 0.27). When univariate outliers were excluded, the results showed that there was a significant difference across the different disciplines for prospects in jobs that could be performed from home, (F (2, 166) = 5.16, p < 0.01). Post hoc analyses with LSD revealed that perceived job prospects for jobs performed from home were significantly lower for Tourism (M = 5.05, SD = 1.31) than for Communications (M = 5.72, SD = 1.12) and IT (M = 5.61, SD = 1.05); there was no significant difference in perceived prospects of jobs performed from home between the Communications and IT disciplines. Results remained the same for perceived job prospects for essential services when univariate outliers were excluded. Standard multiple regression analysis was conducted to examine whether perceived prospects for jobs that could be performed from home and for essential services predicted students’ job security confidence levels. The results revealed that both factors accounted for a significant 4.8% of the variability in job security confidence, R2 = 0.048, F (2, 172) = 4.32, p = 0.02. Perceived prospects for jobs that could be performed from home did not significantly predict job security confidence, B = −0.02, t (172) = −0.18, p = 0.86, but perceived prospects for jobs in essential services did, B = 0.22, t (172) = 2.75, p = 0.01. This indicates that students’ perceptions of the prospects for essential services contributed to their confidence in job security. Similar regression analyses were also conducted for each industry sector. The results revealed that these factors did not significantly account for the variability in job security confidence for Tourism (R2 = 0.023, F (2, 53) = 0.63, p = 0.54) and IT (R2 = 0.048, F (2, 68) = 1.70, p = 0.19). However, these factors did significantly account for the variability in job security confidence for Communications (R2 = 0.17, F (2, 45) = 4.68, p = 0.01). Similar to the previous finding, perceived prospects for jobs that could be performed from home did not significantly predict job security confidence, B = −0.07, t (45) = −0.38, p = 0.72, but perceived prospects for jobs in essential services did, B = 0.46, t (45) = 2.89, p < 0.01. When multivariate outliers were excluded, a similar pattern of findings was observed except for the finding relating to the IT discipline. When multivariate outliers were excluded, perceived prospects for jobs that could be performed from home significantly predicted job security confidence, B = 0.30, t (65) = 2.16, p = 0.03, but not perceived prospects for jobs in essential services, B = 0.08, t (65) = 0.62, p = 0.54. Effects of perceived job prospects on job security confidence across programme types This section of the analysis relates to RQ2, which assesses future job security confidence, across programme types. Students responded on a 7-point Likert scale to three items: “I feel confident about my success in getting a job after graduation”, “I feel confident about retaining my job after graduation” and “I feel confident that I will be able to be in a position where I can do the work which I like”. Items were averaged to form a single index for job security confidence, with higher scores reflecting greater confidence (M = 4.58, SD = 1.36, α = 0.91). A one-way ANOVA was conducted to examine differences in job security confidence across programme types. The results (Table 5) show that there were no significant differences in job security confidence across industry sectors, (F (2, 172) = 1.32, p = 0.27).Table 5. Means and standard deviations for perceived prospects in jobs performed from home, perceived prospects in essential services, and job security confidence across programme types. Variable Overall Tourism Comms IT Mean SD Mean SD Mean SD Mean SD Jobs performed from home 5.35 1.30 5.05 1.31 5.65 1.23 5.39 1.29 Essential services 5.38 1.42 5.54 1.29 5.50 1.47 5.17 1.47 Job security confidence 4.58 1.36 4.51 1.28 4.38 1.57 4.77 1.28 To analyse graduating students’ perceptions regarding job prospects during COVID-19, open-ended responses were coded and analysed using quantitative content analysis, based on extant literature on graduate perceptions relating to future employability and job prospects (e.g. Jackson and Tomlinson, 2020). Students’ perceptions of future graduate employability and job prospects were mixed, with 79 negative, 34 positive and the rest uncertain. Table 6 illustrates the common themes (top five thematic clusters and 50 most cited words and phrases) related to narratives on perceived graduate employability and job prospects.Table 6. Common themes on perceived graduate employability and job prospects. Top 5 themes and 50 most cited words/phrases, with sample respondent narrative 1. Changes to job demand due to COVID-19 restrictions (45) “... Hiring [is] a lot harder … even if tourism companies recover from COVID-19, they would likely rehire retrenched staff instead of new staff to save on training. Also, negotiation of my pay becomes much harder because I will be competing with retrenched or older applicants who have more years of experience than I do.” 2. Hiring practices and policies (31) “As a fresh graduate studying in another country, the impact that COVID-19 is quite negative because of retrenchment … and most employers will be looking for local citizens as employees.” 3. Work-life experiences and employability (24) “As a fresh graduate with very little experience in the field of journalism I feel that companies may not want to hire a fresher as they would have to train from the very beginning. But since I have some experience, I may be considered.” 4. Professional identity and career self-management (19) “In my disciplinary field, individuals must keep up with the fast-changing pace of technology, which puts certain pressure to constantly chase after innovations … the crisis has changed the expectations of graduates when stepping into the workforce. Self-management and digital literacy skills are becoming more important as fresh graduates need to maintain their employability by staying competent.” 5. Impact of work-from-home practices (18) “The crisis will separate what is essential work and has to be done on-site, and what is deemed non-essential enough to be taken offsite/work-from-home ... This allows us graduates to identify which roles or responsibilities in the sector remain critical and essential that will not be replaceable with a work-from-home alternative.” Impact of COVID-19 on career prospects across industry sectors Whilst the above sections relate to students’ perceptions regarding their job prospects (i.e. their ability to attain a job on graduation), this section (RQ3) turns to students’ perceptions regarding their career prospects (i.e. their ability to retain their job in their industry sector). Thus, to assess graduating students’ perceptions of COVID-19’s impact on their career prospects, they were asked how the crisis had impacted their career prospects, and if the impact was generally a positive or negative one. Additionally, students were asked to respond on a 7-point Likert scale to the item “I believe that COVID-19 will have a negative impact on my chosen industry as whole” to assess the extent of their perception regarding the impact of COVID-19. Higher scores on this item reflect a greater negative impact of COVID-19 (M = 3.08, SD = 2.64). A chi-square test of associations was conducted to examine the difference in students’ perceptions of their career prospects across gender. The analysis revealed that there was significant association between perceived impact aboutand gender, χ(1) = 6.98, p < 0.01, indicating that female students were more likely to perceive the impact of COVID-19 to be negative (Figure 2). An independent samples t-test also revealed that female students (M = 5.49, SD = 1.49) perceived the impact of COVID-19 to be more negative than did male students (M = 4.55, SD = 1.87), t (124.12) = −3.23, p < 0.01.Figure 2. Clustered bar chart illustrating the number of male and female students indicating the perceived impact of COVID-19 (positive or negative). Similar analyses were conducted to examine the differences in students’ perceptions of COVID-19’s impact on their career prospects across industry sectors. A chi-square test of association showed a significant association between COVID-19’s impact and sector type, χ(2) =1 2.22, p < 0.01. This indicates that Tourism students were more likely to perceive COVID-19’s impact as negative than were Communications and IT students (Figure 3). A one-way ANOVA further supported this by revealing a significant difference in the extent of COVID-19’s impact, F (2, 130) = 18.90, p < 0.01. Post hoc analyses with Tukey’s HSD demonstrated that Tourism students perceived the impact of COVID-19 to be more negative than did both Communications students (M = 4.83, SD = 1.60), p < 0.01, 95% CI [0.40, 2.01], and IT students (M = 4.13, SD = 1.72), p < 0.01, 95% CI [1.17, 2.66]. There was no difference in perception between Communications and IT students.Figure 3. Clustered bar chart illustrating students across sector types indicating the perceived impact of COVID-19 (positive or negative). Crises such as COVID-19 may trigger volatile career environments and labour market conditions. This may result in a heterogeneity of impacts among different industry sectors, occupations and job functions, imposing contrasting employability outcomes, positive or negative, on different careers and individuals. Consequently, students were also asked to explain why they believed that the COVID-19 crisis had a positive or negative impact on their career prospects. Figure 4 summarises the perceived positive and negative COVID-19-induced impacts on career prospects (top three clusters and word frequency analysis) expressed in the respondents’ narratives. As illustrated in Figure 4, the most commonly articulated perceived negative impacts of COVID-19 on employability outcomes were: (1) reduced manpower demand, hiring freezes and workplace retrenchments in the industry sector or related occupations; (2) competition among graduates for a limited number of jobs and changes in hiring practices or policies (e.g. restrictions on hiring of non-locals, and work experience requirements); and (3) COVID-19-related restrictions, or changes to jobs in the industry sector (e.g. restrictions on physical/face-to-face interaction and imposed safe management measures). With regard to perceived positive impacts, the most commonly articulated narratives related to: (1) job roles and occupations that were able to function remotely (work-from-home) and considered as essential services; (2) increased demand for positions for specific job skills, function or occupations in the industry sector (e.g. IT, cybersecurity and digital media communications); and (3) opportunities for upskilling and emphasis on adaptability (e.g. support for new skillsets, transferability of skills and knowledge, and being adaptable in the ‘new normal’).Figure 4. Analysis of respondents’ narratives regarding the positive or negative impacts from COVID-19. Discussion and conclusions This study sought to investigate the employability concerns and employment prospects of undergraduate students graduating during the COVID-19 pandemic from 2020 to 2022. As discussed, sustained crises such as COVID-19 may trigger volatile graduate employability environments and labour market conditions. Moreover, there may be notable heterogeneity of impacts between different industry sectors, occupations, and job functions (Akkermans et al., 2020; del Rio-Chanona et al., 2020; Hite and McDonald, 2020; Pedersen et al., 2020), thus affecting students’ self-perceptions regarding their job and career prospects. Consequently, this may also influence their future job security confidence. Given these considerations, three key research questions were explored (summarised in Table 7). Firstly, the study examined how perceived job prospects for jobs that could be performed from home and those in essential services might impact graduating students’ future job security confidence levels (RQ1). Secondly, it explored whether job security confidence levels differed depending on programme type (i.e. Tourism, Communications and IT) (RQ2). Lastly, it addressed the question of whether their perceptions would impact graduating students’ perceived career prospects and future job security confidence in each of the three industry sectors (RQ3). As discussed in the literature, graduates’ self-perceptions about employability and employment prospects may be based on their perceptions regarding job and career prospects, personal aspirations and ability to successfully compete based on existing alternatives and conditions in the labour market (Jackson and Tomlinson, 2020; Saher and Hussain Ch, 2019). Hence, in the context of this study, job prospects relate to graduates’ perceived ability to attain a job on graduation, while career prospects relate to their perceptions about their ability to retain their job in their industry sector. These concerns may be heightened during a crisis, when potentially adverse employment conditions may affect job security confidence and future employment prospects (Baert et al., 2020; Hite and McDonald, 2020). Moreover, there may also be variations in employability outcomes across industry sectors, due to differences in perceived job prospects and future job security confidence levels between jobs that can be performed from home and those considered as essential services (Dingel and Neiman, 2020). These key employability dimensions were analysed in the preceding results section.Table 7. Summary of research question and findings. Research question Summary of findings RQ1: How do perceived job prospects in jobs that can be performed from home and perceived prospects in essential services impact graduating students’ future job security confidence? There were no differences in perceived job prospects in jobs that could be performed from home and jobs in essential services Students’ perceptions of the prospects available in essential services contributed to their confidence in job security Students’ perceptions of the prospects available in jobs that could be performed at home did not affect their confidence in job security RQ2: Does job security confidence significantly differ by programme type? There were no significant differences in job security confidence across programmes RQ3: Would their perceptions impact graduating students’ perceived career prospects and future job security confidence in each of the three industry sectors? On career prospects - tourism students perceived the impact of COVID-19 to be more negative than did communications students and IT students. There was no difference in perception between communications and IT students On career prospects and gender - female students perceived the impact of COVID-19 to be more negative than did male students On job security confidence by industry sector - there were no significant differences in job security confidence across industry sectors. Job security confidence was significantly different for communications students. For communications students, perceived career prospects in essential services played a role in job security confidence The findings indicate that the students strongly believe that the COVID-19 crisis had a positive impact on jobs that could be performed from home and those in essential services (RQ1). However, there were no differences in perceived job prospects for jobs that could be performed from home and jobs in essential services. Moreover, students’ perceptions of the prospects available in essential services contributed to their confidence in job security. Conversely, students’ perceptions of the prospects available in jobs that could be performed at home did not affect their future job security confidence. These findings were in contrast to those of other research conducted in 2020, during the earlier stages of the pandemic (e.g. Garrote Sanchez et al., 2020; Honorati et al., 2020), in which the least vulnerable jobs were those that could be performed from home. Likewise, Garrote Sanchez et al. (2020) found that the risk of job loss during the pandemic was highest for non-essential jobs. This may explain why this study found that the confidence students had in job security stemmed from their perception of the prospects available in essential services. These observations were also noted in the analysis of the qualitative narratives from respondents, wherein the top five themes (Table 6) related to COVID-19-induced impacts on graduate employability were: (1) changes to job demand due to COVID- 19 restrictions, (2) hiring practices and policies, (3) work-life experiences, (4) professional identity and career self-management, and (5) impact of work-from-home practices. On the question of whether job security confidence differs depending on programme type (RQ2), the findings suggest that job security confidence was similar across students from Tourism, Communications and IT. This is an interesting finding, albeit contrary to observations such as that of Gupta (2020) that jobs such as digital marketing, data science and cybersecurity have survived better than jobs in tourism and hospitality. It is encouraging to note that, despite economic estimates regarding the severe impacts on the global tourism sector (World Bank, 2022), this study finds that the job security confidence among Tourism students did not differ from that of the Communications and IT students. As supported by the results of the study, students’ favourable view of the prospects available in alternative occupations in essential services and jobs that could be performed from home could indeed play a significant role in their job security confidence. Lastly, this study examined the question of whether graduating students’ self-perceptions would impact their perceived career prospects and future job security confidence in each of the three industry sectors (RQ3). Compared with Communications and IT students, Tourism students had a less favourable view of how the crisis had impacted their employment prospects. There was no difference in perceptions between Communications and IT students. Consistent with Kabeer et al.’s (2021) study investigating gender differences in the South Korean labour market, this study found gender differences in how students perceived the impact of the crisis on their career prospects, with female students recording significantly more negative perceptions of the impact of COVID-19. Cotton et al. (2021) observed similar gender concerns, particularly in relation to wider social, occupational and (in)equality debates. Extant research suggests that women are affected more in part due to a higher concentration of females in hospitality, casualised employment and care responsibilities, making them more vulnerable to volatile employability conditions (Cotton et al., 2021; Kabeer et al., 2021). In the present study, there were no differences in job security confidence across the three industry sectors. Interestingly, when examining job security confidence levels within individual industry sectors, the findings indicated that perceived job prospects affected Communication students’ job security confidence levels with more frequency than Tourism and IT students. In particular, the findings revealed that for Communications students, confidence in getting or retaining a job was directly affected by how they perceived job prospects in essential services. It is important to note that the outlook for media and communications sectors is positive, even though these jobs may not be seen as essential services (Fine et al., 2020). This is consistent with the findings from this study: considering the positive job outlook for media and communications, it makes sense that the Communication students’ level of job security confidence was not different from that of the Tourism and IT students. However, the findings showed that, when essential services were considered, Communications students’ confidence in retaining or getting a job was affected. This can be explained by the fact that media and communications jobs were not seen as essential in public discourse. Similar sentiments were noted in the qualitative analysis of the most common narratives on whether COVID-19-induced impacts were deemed to be positive or negative (Figure 4). In times of drastic change, future job security and longer-term career prospects may lead to a perceived need for continued professional training and development post-graduation. The recent employability discourse has emphasised the value of lifelong learning, continued training and self-development as a strategy for adapting to and evolving with labour market demands (Kornelakis and Petrakaki, 2020; Tomlinson, 2012). Moreover, as discussed, there is a shift from traditional institution- or organisation-focused career trajectories to self-managed and self-directed careers. Thus, graduates need to pivot towards a mindset and relevant skills that will enable them to effectively identify, develop and navigate career pathways appropriate to their own capabilities, circumstances and goals. Pool and Sewell (2007) suggest that, beyond individual skills, knowledge and personal attributes, graduate success and satisfaction are more likely if they develop higher-order self-beliefs in their employability – i.e. self-efficacy, self-confidence and self-esteem. These components can be cultivated when students practice and reflect on their career development learning, work and life experiences, subject knowledge, professional skills and emotional intelligence. As Tomlinson (2012) highlights, and the current study suggests, there is a need to map graduate employability more comprehensively with the shifting dynamics of the labour market and its relationship with higher education graduate outcomes. Today’s employers accentuate the need for graduates to be agile, adaptable and technically savvy and to be able to transfer their skills across diverse contexts (Jackson and Tomlinson, 2020; Kornelakis and Petrakaki, 2020; Leach, 2017; Shobha and Johnson, 2021). However, crisis events exacerbate the complexities of graduates’ transition to the labour market as they adapt and align themselves to the future labour market demands during a time of uncertainty. Therefore, beyond skill-based considerations, policy makers and higher education institutions need to be cognizant of the variances in individual circumstances and responses to this crisis, and to support graduates by facilitating their ability to respond to, recover from and manage COVID-19-induced career shocks. The students who responded to the study demonstrated an acute awareness that having agility, adaptability and transferability of skills and knowledge across different contexts was paramount. Thus, this should be part of the higher education graduate employability discourse. Moreover, the findings suggest the need to identify job vulnerability among students in programmes of study that are more drastically impacted by the crisis than others. Using such data to map out employability and career support for students will be essential to the value that higher education brings to graduating students in times of change. The present study contributes to knowledge and practice in several respects. In terms of knowledge contributions, the analysis of the extant literature and findings builds on the discourse regarding the key thematic dimensions impacting graduate employability and employment prospects during a sustained crisis such as COVID-19. Since this study occurred across various stages of the pandemic, it updates and contrasts with earlier published COVID-related employability research. Furthermore, it focuses on COVID-salient employability factors, such as jobs being performed from home and those considered as essential services, across industry sectors. This factor is significant, as it is unique to the current and future potential pandemic scenarios, where social distancing and workplace restrictions may be the new normal. This is a consideration that was not a dominant factor in previous crises. Whilst prospects for recovery are anticipated in numerous economies and sectors, it is envisioned that the implications from this and other potential future pandemics will have much wider and longer-term impacts (Hall, 2021; Najam, 2021). In terms of practice, this study contributes towards an understanding of the perceptions of graduating students' employability concerns as they prepare to enter the workforce during a sustained crisis. Moreover, as suggested in the above discussion and in other recent discourse, it is likely that the pandemic’s ramifications for employability and transformation of the nature of work will remain for decades to come (Couclelis, 2020; Kolata, 2021; Shobha and Johnson, 2021). Therefore, there is potential for the endurance and relevance of the study’s contributions beyond the present pandemic. Nevertheless, the researchers acknowledge the limitations of the study, and the boundaries of its parameters – respondents from only three academic disciplines, the study location and the COVID-19 period. As a convenience sample of students from a university in Singapore was utilised, the researchers acknowledge the limitation in the generalisability of the findings. Future research might expand the investigation to the institution’s other locations (including, but not limited to Australia, Dubai and Myanmar). Additionally, while the analysis and discussion in this paper focus on the employment, workforce and sectoral thematic dimensions, future research could expand this discourse to include related employability concerns such as teaching–employability relationships, implications for and from institutional and policy interventions, and changes to teaching and learning in higher education. As the global pandemic continues to evolve, and economies gradually emerge from the crisis, the researchers intend to develop future longitudinal research and focus-group studies to enrich the findings from this exploratory study. Nonetheless, the current findings offer practical insights and context concerning graduating students’ perceptions regarding their employment prospects and future job security confidence during a time of global crisis. ORCID iD Eunice Tan https://orcid.org/0000-0002-1396-762X The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article. ==== Refs References Akkermans J Richardson J Kraimer ML (2020) The Covid-19 crisis as a career shock: Implications for careers and vocational behaviour. Journal of Vocational Behaviour 119 : 103434. DOI: 10.1016/j.jvb.2020.103434. Baert S Lippens L Moens E , et al. (2020) How Do We Think the COVID-19 Crisis Will Affect Our Careers (If Any Remain)? Essen. Geneva, Switzerland: Global Labour Organisation. Capone V Marino L Park MSA (2021) Perceived employability, academic commitment, and competency of university students during the COVID-19 Pandemic: An exploratory study of student well-being. Frontiers in Psychology 12 . doi: 10.3389/fpsyg.2021.788387. Castro FG Kellison JG Boyd SJ , et al. (2010) A methodology for conducting integrative mixed methods research and data analyses. Journal of Mixed Methods Research 4 (4 ): 342–360.22167325 Coates B Cowgill M Chen T , et al. (2020) Shutdown: Estimating the COVID-19 Employment Shock. Carlton: Grattan Institute. Cotton E Beauregard TA Keles JY (2021) Gender equalities: what lies ahead. Work, Employment and Society 35 (4 ): 615–620. Couclelis H (2020) There will be no post-COVID city. Environment and Planning B: Urban Analytics and City Science 47 (7 ): 1121–1123. del Rio-Chanona RM Mealy P Pichler A , et al. (2020) Supply and demand shocks in the COVID-19 pandemic: an industry and occupation perspective. Oxford Review of Economic Policy 36 (Supplement_1 ): S94–S137. Dingel JI Neiman B (2020) How many jobs can be done at home? Journal of Public Economics 189 : 104235. DOI: 10.1016/j.jpubeco.2020.104235.32834177 Fine D Klier J Mahajan D , et al. (2020) Saving and recreating employment during COVID-19: how to rebuild and reimagine jobs amid the coronavirus crisis. Available at: https://www.mckinsey.com/industries/public-sector/our-insights/how-to-rebuild-and-reimagine-jobs-amid-the-coronavirus-crisis# Garrote Sanchez D Gomez Parra N Ozden C , et al. (2020) Which Jobs Are Most Vulnerable to COVID-19? What an Analysis of the European Union Reveals. Washington: World Bank. George D Mallery P (2010) SPSS for Windows Step by Step: A Simple Guide and Reference 17.0 Update. 10th edition. Boston: Pearson. Gupta A (2020) Jobs That Withstood the Impact of COVID-19. Bangalore, Karnataka: Deccan Herald. Available at: https://www.deccanherald.com/supplements/dh-education/jobs-that-withstood-the-impact-of-covid-19-847944.html. Hall JL (2021) Governance: struggle and strife–or synergy and success–in the trans‐COVID era. Public Administration Review 81 (1 ): 7–11.34149104 Hite LM McDonald KS (2020) Careers after COVID-19: challenges and changes. Human Resource Development International 23 (4 ): 427–437. Honorati M Yi S Choi T (2020) Assessing the Vulnerability of Armenian Temporary Labour Migrants during the COVID-19 Pandemic. Social Protection and Jobs Discussion Paper (No. 2003). Washington: World Bank. Jackson D (2014) Factors influencing job attainment in recent bachelor graduates: evidence from Australia. Higher Education 68 (1 ): 135–153. Jackson D Tomlinson M (2020) Investigating the relationship between career planning, proactivity and employability perceptions among higher education students in uncertain labour market conditions. Higher Education 80 : 435–455. DOI: 10.1007/s10734-019-00490-5. Kabeer N Razavi S van der Meulen Rodgers Y (2021) Feminist Economic Perspectives on the COVID-19 Pandemic. Feminist Economics 27 (1–2 ): 1–29. Leach T (2017) It seems at the moment my career is dependent on factors outside of my control: reflections on graduates’ experiences of employment and career enactment in an era of economic uncertainty and austerity. British Journal of Guidance and Counselling 45 (2 ): 188–198. Kolata G (2021) Past Pandemics Remind Us COVID Will Be an Era, Not a Crisis that Fades. New York, NY: The New York Times, Available at: https://www.nytimes.com/2021/10/12/health/when-will-covid-end.html Kornelakis A Petrakaki D (2020) Embedding employability skills in UK higher education: between digitalization and marketization. Industry and Higher Education 34 (5 ): 290–297. Matsouka K Mihail DM (2016) Graduates’ employability: what do graduates and employers think? Industry and Higher Education 30 (5 ): 321–326. Ministry of Trade and Industry, Singapore (MTI) (2021a) Economic survey of Singapore 2020. Available at: https://www.mti.gov.sg/-/media/MTI/Resources/Economic-Survey-of-Singapore/2020/Economic-Survey-of-Singapore-2020/FullReport_AES2020.pdf Ministry of Trade and Industry, Singapore (MTI) (2021b). Economic survey of Singapore: third quarter 2021. Available at: https://www.mti.gov.sg/Resources/Economic-Survey-of-Singapore/2021/Economic-Survey-of-Singapore-Third-Quarter-2021 Montenovo L Jiang X Rojas FL , et al. (2020) Determinants of Disparities in COVID-19 Job Losses. Cambridge: National Bureau of Economic Research. O’Leary S (2015) Integrating employability into degree programmes using consultancy projects as a form of enterprise. Industry and Higher Education 29 (6 ): 459–468. Najam A (2021) I Spoke to 99 Big Thinkers About What our ‘World After Coronavirus’ Might Look Like – This is What I Learned. Melbourne: The Conversation. Available at: https://theconversation.com/i-spoke-to-99-big-thinkers-about-what-our-world-after-coronavirus-might-look-like-this-is-what-i-learned-146986 Nandy M Lodh S Tang A (2021) Lessons from Covid-19 and a resilience model for higher education. Industry and Higher Education 35 (1 ): 3–9. Padhan R Prabheesh KP (2021) The economics of COVID-19 pandemic: a survey. Economic Analysis and Policy 70 : 220–237.33658744 Pedersen CL Ritter T Di Benedetto , et al. (2020) Managing through a crisis: managerial implications for business-to-business firms. Industrial Marketing Management 88 : 314–322. Pool LD Sewell P (2007) The key to employability: developing a practical model of graduate employability. Education and Training 49 (4 ): 277–289. Rothwell A Herbert I Rothwell F (2008) Self-perceived employability: construction and initial validation of a scale for university students. Journal of Vocational Behaviour 73 (1 ): 1–12. Rothwell A Jewell S Hardie M (2009) Self-perceived employability: investigating the responses of post-graduate students. Journal of Vocational Behaviour 75 (2 ): 152–161. Saher U Hussain Ch A (2019) A comparison of self-perceived employability of graduates from public and private Universities of Punjab. Bulletin of Education and Research 41 (1 ): 119–130. Shih TH Fan X (2008) Comparing response rates from web and mail surveys: a meta-analysis. Field Methods 20 (3 ): 249–271. Shobha CV Johnson B (2021) Employability framework in the post-Covid scenario: a literature review. Abhigyan 39 (2 ): 28–37. Tomlinson M (2012) Graduate employability: a review of conceptual and empirical themes. Higher Education Policy 25 (4 ): 407–431. World Bank (2022) Global Economic Prospects, January 2022. Washington, DC: World Bank. DOI: 10.1596/978-1-4648-1758-8.
PMC009xxxxxx/PMC9535224.txt	==== Front Small Bus Econ Small Business Economics 0921-898X 1573-0913 Springer US New York 689 10.1007/s11187-022-00689-4 Article Different response paths to organizational resilience http://orcid.org/0000-0003-4269-1826 Shepherd Dean A. [email protected] 1 Williams Trenton A. 2 1 grid.131063.6 0000 0001 2168 0066 University of Notre Dame, Notre Dame, IN USA 2 grid.411377.7 0000 0001 0790 959X Indiana University, 107 S Indiana Ave, Bloomington, IN 47405 USA 6 10 2022 2023 61 1 2358 7 9 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. An essential yet understudied aspect of organizational responses to an environmental shock is how managers interpret and respond to their new environments and address post-shock environmental challenges. The post-shock managerial response process can be intense and highly consequential as actors often must challenge the status quo in a compressed period. Decisions are frequently “life or death” in terms of organizational survival. This study analyzed data on resilient organizations’ responses to the COVID-19 crisis and offered a model of organizational response paths to resilience. Our grounded theorizing offers three primary contributions: (1) we add richness to the distinction between organizations that are resilient or not by highlighting different response paths within the organizational-resilience category; (2) we complement the notion of post-adversity growth by explaining how organizations grow during adversity; (3) we move beyond explanations of resilience based on differences in organizations’ resource endowments and instead provide new insights into different paths to resilience based on differences in how organizations interpret and respond to the same adverse event. There are different ways organizations make the most out of a surprising challenge to enhance performance, adjust, and pivot for new opportunities. The COVID-19 pandemic has challenged organizations in different ways—some experienced near-exponential increases in demand, whereas others saw their entire business evaporate overnight. Despite a continuum in the severity of these challenges, they require resilience. But how does resilience happen in organizations? Our study examines different responses to a challenge that, while originating from the same adverse event (COVID-19 pandemic), impacted organizations and their decision making differently. We find three patterns of responses that provide options for how organizations might approach challenges based on the impact they experience. First, some organizations fell into sudden, exponential demand—requiring simple decision-making rules to make incremental changes to support rapid scaling. Second, other organizations faced operational challenges and found ways to repurpose existing structures to maintain business operations. Finally, some organizations appraised their situation as an imminent threat to organizational survival, requiring rapid, wholesale changes to the business model in the form of pivots. Thus, the principal implication of this study is that organizations have different experiences from the same precipitating event, and they should ensure they align firm decision making, strategic initiatives, and operational activities to best promote resilience. Keywords Organizational resilience Adversity Entrepreneurship Adaptation Decision-making JEL Classification S01 D21 D62 D80 D91 issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmc “We cannot change the cards we are dealt. Just how we play the hand.” – Randy Pausch’s Last Lecture (Carnegie Mellon University) Introduction In recent years, there has been increased interest in understanding how organizations and people are resilient to adverse events (Battisti et al., 2019; Darkow, 2019; Herbane, 2019; Kahn et al., 2018; Williams & Shepherd, 2016a). Indeed, while globalization has spurred unprecedented increases in the scale and efficiency of organizations, it has also produced increased vulnerability as the widespread interdependence of systems can damage organizational performance when global supply chains are disrupted (Interos, 2021). Therefore, there is a critical need to understand how organizations maintain functioning—and potentially thrive (Battisti et al., 2019; Vera et al., 2021)—in the face of adversity that occurs in a variety of forms: environmental shifts, disruptive events, technological change, economic pressure, and so forth (Bruyaka, Philippe & Castañer, 2018; Eggers & Park, 2018; Park & Rogan, 2019; Shepherd & Williams, 2020). Resilience is a process that builds the capacity “to interact with the environment in a way that positively adjusts and maintains functioning prior to, during, and following adversity” (Williams et al., 2017: 742). While maintaining functioning in the face of adverse events is important, a critical but overlooked issue in the study of organizational resilience concerns how some actors may prosper, enhancing (rather than merely maintaining) functioning in the face of even the most extreme adversity (e.g., leaders thriving in adverse contexts (Vera et al., 2021)) or experiencing personal growth after recovering from a traumatic event (Maitlis, 2009, 2012, 2020). Studying the differing degrees to which resilient organizations respond to the onset of adversity is essential as such responses are highly consequential to organizational performance and require adaptive activities to manage effectively. The literature on resilience suggests that adverse events are “low-probability, high-impact negative shocks or jolts to a focal individual’s or organization’s environment that is potentially highly disruptive to well-being” (Shepherd & Williams, 2020: 2, emphasis added). However, impressions of adverse events may be unnecessarily negative and unlikely to represent everyone’s experience—hence why adverse events are potentially disruptive to organizations. From the current perspective, the resilience outcome in the face of an adverse event is maintaining positive functioning—as opposed to a loss of functioning that endures (chronic dysfunction) or takes time to return to normal (recovery trajectory) (Bonanno, 2004; Williams et al., 2017). However, there is evidence that facing adversity can increase positive functioning (Williams & Shepherd, 2016b, 2018). For example, Williams and Shepherd (2016a, 2021) show that an adverse event can present potential opportunities to alleviate suffering above and beyond the scope of the adversity and can help address chronic issues, such as poverty, homelessness, and joblessness. Similarly, Maitlis (2009) shows how some people who suffer from a traumatic injury recover and eventually benefit—also known as post-traumatic growth (Calhoun & Tedeschi, 2014). However, even this post-adversity growth involves a drop in functioning before recovery and, ultimately, increased functioning (vis-à-vis the pre-adversity functioning). Despite the advances in research on organizational resilience in the face of adversity (Ahmed et al., 2021; Williams et al., 2017), certain unchallenged assumptions have limited research advancements. Indeed, the resilience literature and its reliance on the dichotomous categorization of organizations in response to adversity (i.e., resilient or not resilient) lead to gaps in our understanding of adversity and organizational resilience. Specifically, there is a gap in our understanding of differences in organizations’ experiences and interpretations of the same adverse event and, subsequently, their different response paths to different forms and/or degrees of organizational resilience. There is also a gap in our understanding of the upside potential of adverse events more immediately than post-adversity growth. If there is an upside, then we need to understand how this upside is achieved. In seeking to address these gaps in our current knowledge, we ask the following questions: how and why do resilient organizations differ in their responses to an adverse event, and how do these different responses shape degrees of enhanced functioning? To address this question, we conducted a qualitative study of organizations that all appeared to be resilient to varying degrees in the face of the ongoing COVID-10 pandemic. We chose to explore resilience in the face of the COVID-19 pandemic because it had a broad impact on business across a wide range of industries and thus allowed us to explore different challenges and responses to the same adverse event (i.e., because events can vary in adversity (Shepherd & Williams, 2020) investigating one event allows us to focus on the differences in organizational responses). We identified and analyzed data on 34 responses by resilient organizations that could be theoretically revealing to our inquiry, drawing on both qualitative interviews and secondary data. Specifically, we identified organizations that demonstrated various degrees of resilience in response to the same adverse event, which outside media sources observed. The primary insight of our qualitative analysis of these resilient organizations and their responses is the identification of three different response paths of organizational resilience that unfolded after the onset of the COVID-19 pandemic and public health responses to it starting in March 2020. We use the term “response path” consistent with the psychology literature on resilience (Bonanno, 2004), which, in an organizational context, refers to the sequence of decisions and actions an organization implements to interpret its new context and then adapt to the perceived features of the adverse external environment. Indeed, we found that despite facing a common adverse event, the resilient organizations we studied experienced and interpreted the adversity differently, which then initiated different response paths to organizational resilience. Our grounded theorizing and model make three primary contributions to the literature, which we briefly preview before detailing qualitative analysis and findings. First, one research stream explores why some organizations recover well from the negative impact of environmental jolts (Benner & Zenger, 2016; Meyer, 1982; Stieglitz et al., 2016; Wenzel et al., 2020). A largely separate research stream explores why some organizations can maintain positive functioning in such adversity (for a review, see Williams et al., 2017; e.g., Battisti et al., 2019; Caza et al., 2020). The organizations we studied experienced and interpreted the focal adverse event differently, triggering different response paths to organizational resilience. Therefore, we move beyond the dichotomous distinction between resilient and non-resilient organizations to add richness to the notion of organizational resilience. Second, a small but important stream of research on recovery from an adverse event explores how, in the long run, experiencing adversity (by organizational members) can lead to positive outcomes, including for organizations, post-adversity growth (at the individual level see Maitlis, 2009, 2012, 2020). Our findings contribute to this individual-level research on post-adversity growth. Some organizations we studied experienced growth amid adversity without having first experienced the disruption that characterizes post-adversity growth. Finally, organizations are more resilient to adverse events when they have substantial resource endowments (Carmeli & Markman, 2011; Lengnick-Hall et al., 2011; Stephens et al., 2013), flexible decision making (Rahmandad & Repenning, 2016; Shepherd et al., 2017), learning capabilities (Battisti et al., 2019), and innovative and improvisational behavior (Baker & Nelson, 2005; Dewald & Bowen, 2010). Although adverse events differ in their geographical scope, duration, and severity (Williams et al., 2017), the same adverse event is assumed to similarly affect firms with comparable resources and capabilities. From this perspective, differences in adversity response effectiveness are associated with heterogeneity in pre-adversity stocks and/or the adaptive responding capacity of an organization. However, we found that the same adverse event impacted organizations differently (regardless of similar resource endowments). This finding is more consistent with the psychology literature on resilience (Bonanno, 2004), which finds that adversity presents only a potential for disruption, as people interpret, respond to, and act upon common adversity differently. Therefore, we provide insights into different forms of resilience (which we label capitalizing, repurposing, and realigning) based on their use of their resources rather than differences in the size of the resource endowment or the nature of the adverse event. In doing so, we integrate well-established insights at the individual level of resilience into organizational-level theory. Having briefly previewed our findings and contributions, we now turn to the theoretical background and analysis. Theoretical background Adversity is a ubiquitous part of life and has thus featured prominently in organizational studies (see Bundy et al., 2017; Williams et al., 2017). For example, most people are exposed to at least one and often several potentially traumatizing experiences in their lifetimes (Ogle et al., 2013). Organizations are similarly exposed to a wide range of events that can be highly disruptive (Taleb, 2007). Adversity comes from many sources, including natural disasters, industry dynamics, organizational error, accidents, and so forth (Boin, 2005; Laufer & Coombs, 2006; Perrow, 1994; Quarantelli & Perry, 2005; Pfeffer & Salancik, 2003; Quarantelli, 1998; Roux-Dufort & Lalonde, 2013). In many cases, large-scale adversity is described as a disruptive event, or a sudden onset environmental shock or jolt that is surprising, unstructured, unexpected, and negative in nature (Meyer, 1982; Rosenthal, 2003; Topper & Lagadec, 2013) that threatens the very survival of the focal actor (i.e., individual, organization, community, etc.) (Lagadec, 2007; Pearson & Clair, 1998; Sayegh, Anthony, & Perrewe, 2004). From this perspective, the sudden onset of adversity implies time pressure and the need for coordination among multiple stakeholders to address challenges (Sommer & Pearson, 2007). For example, adverse events such as emergent disasters (Bundy et al., 2017), political upheaval (Carroll & Delacroix, 1982), and economic downturns (Bradley et al., 2011) may be disruptive and devastating. Indeed, some organizations that face an adverse event suffer a drop in positive functioning and may then bounce back over an extended period (i.e., recover (Beunza & Stark, 2003) or turn around (Zimmerman, 1989)), whereas others experience chronic low performance and/or termination (Seckler, Fischer, & Rosing, 2021; Williams et al., 2020). In contrast, some organizations are resilient to adverse events, experiencing minimal disruption to functioning (Mittermaier et al., 2022a; Powley, 2009), while others may even grow from an adverse event, using it as a “crucible” to come to a “new or altered sense of identity” (Bennis & Thomas, 2002: 63; Roberts et al., 2005). While adversity can vary from discrete events such as natural disasters (e.g., bushfires (Shepherd & Williams, 2014; Williams & Shepherd, 2016b, 2018) and earthquakes (Williams & Shepherd, 2016a, 2021)) and man-made disasters (e.g., refugees fleeing war in their home countries (Mittermaier et al., 2022a, 2022b)), it also manifests in longer-term processes of chronic adversity such as poverty (Chatterjee et al., 2022; Shepherd, Parida & Wincent, 2021), the intersectionality of dirty work, slums, and caste (Shepherd et al., 2022), and “permanent” refugees (Shepherd et al., 2020). Indeed, it has been argued by some (e.g., Roux-Dufort, 2007, 2016; Shrivastava, 1992; Turner, 1976) that the actual “event” of a crisis is a discrete flashpoint derived from a longer, incubated process. This notion of an incubated crisis suggests that adversity may grow, ebb, and flow, interacting with organizational responses over time (see Williams et al., 2017 for review). In sum, recent research has revealed that organizations are influenced by the contextual features of adversity, especially its duration and degree of impact. However, as has been established by foundational scholarship (e.g., Christensen & Bower, 1996; Finkelstein, 1997; Pfeffer & Salancik, 2003), organizations are not simply acted upon by environmental forces but produce different interpretations and then responses that allow them to manage and capitalize on environmental conditions (i.e., constraints and opportunities, etc.) that shape the relationship between adversity and organizational outcomes (i.e., performance, failure, etc.). Therefore, while acknowledging the diverse forms of adversity that shape organizations, we are interested in isolating and understanding different organizational responses. To do so, we sought to understand how responses vary across organizations facing the same adverse event (i.e., adversity is held constant). Responding to environmental changes Recovering from adversity While resilience implies the maintenance of functioning in the face of adversity, a recovery response results from (1) a significant loss in functioning that then (2) is restored over time. Adverse events often disrupt organizational functioning. For example, recent global crises, such as the 2008 financial crisis and the COVID-19 pandemic, resulted in significant organizational disruptions: lost jobs, customers, and sources of revenue and even the failure of organizations (Crayne, 2020; Crosina & Pratt, 2019; Giones et al., 2020; Martinez et al., 2019). Indeed, Meyer (1982: 515) described that an environmental jolt has a disruptive impact on organizations and has resulted in research seeking to explain how organizations can overcome their disrupted functioning to recover and return to the pre-jolt status quo (Lalonde & Roux-Dufort, 2010). Crisis management can facilitate the recovery from a loss of positive functioning (Ballesteros et al., 2017; Bundy & Pfarrer, 2015; Christianson et al., 2009; Stam et al., 2018). In particular, Wenzel and colleagues (2020) highlight four strategies for a crisis response: (1) retrenchment to stabilize performance and simplify decision making and activities (Benner & Zenger, 2016; Gartenberg, 2014; Pearce & Robbins, 1994; Robbins & Pearce, 1992), (2) perseverance to maintain current business activities because frequent changes can be distracting and ineffective (Pacheco-de-Almeida, 2010; Stieglitz et al., 2016; Wenzel et al., 2020), (3) innovation to facilitate strategic renewal (Baker & Nelson, 2005; Helfat, 1997), and (4) exit (i.e., failure) as a way of cutting losses and allowing remaining resources to be redeployed elsewhere (Argyres et al., 2015; Burgelman, 1996). While crisis management can help reduce losses and ease the path to recovery, other research explores improvisational tactics that facilitate recovery. Indeed, organizations that are more effective at recovering from a crisis event are those that can improvise (Drabek, 1985; Stallings & Quarantelli, 1985), rapidly mobilize resources and capabilities (Kreps & Bosworth, 1993; Neal & Phillips, 1995; Shepherd & Williams, 2014), and coordinate organizational members (Dynes, 2003; Wenger et al., 1987). Furthermore, efforts to rapidly respond to challenges can facilitate a decreased recovery period, allowing organizations to “bounce back” quickly to their pre-crisis functioning levels (Grattan et al., 2017; Gunderson, 2000). However, bouncing back1 to pre-adverse event functioning may be less than ideal, as returning to the status quo may “have [negative] ramifications and implications beyond those initially imagined or planned” (Tsoukas & Chia, 2002: 568). Indeed, organizations seeking to bounce back by replicating former processes and business activities may experience conflicting results (D’Adderio, 2014) due to a potentially damaging misfit between their new business environments and the previous status quo. Therefore, bouncing back could result in “a crisis [that] would never end because organizations would always fail to reestablish the prior status quo,” which should perhaps not even be a goal in the first place (Darkow, 2019: 151). Resilience to adversity Although the assumption is that adverse events cause organizational disruption (Comfort et al., 2010; e.g., Meyer, 1982), some organizations are resilient to these adverse events (Alexander, 2013; Linnenluecke & Griffiths, 2015; Sutcliffe & Vogus, 2003; Wildavsky, 1988). A resilient response to adversity is not uncommon. Indeed, despite assumptions to the contrary, resilience is the most common individual response to adversity compared to other outcomes (e.g., chronic dysfunction, recovery, etc.) (see Galatzer-Levy et al., 2018 for a meta-analysis and review). Organizations can enhance resilience before an adverse event by developing resources (e.g., through financial (Bradley et al., 2011; Carmeli & Markman, 2011), cognitive (Lengnick-Hall et al., 2011; Thomas et al., 1993), behavioral (Boin et al., 2010; Weick & Sutcliffe, 2011), and emotional (Stephens et al., 2013) endowments (Williams et al., 2017)). Therefore, there have been efforts to explore how organizations can establish processes, routines, and business models to withstand potentially disruptive external forces. Furthermore, the literature on preventing adversity has emphasized developing risk-assessment systems that help anticipate and avoid crises, which involves collecting and analyzing extensive data from organizations and their environments (Gephart et al., 2009). While risk reduction is an understandable strategy, even the most elaborate risk-assessment models have “severe shortcomings... [as] risk assessment is tied to potential threats that need to be known in advance,” which is difficult due to human fallibility and highly interrelated systems that make the number of variables required to accurately determine risks unmanageable (Darkow, 2019: 147, emphasis added). In much of the extant research, the distinction between resilient and non-resilient organizations and organizations that are quicker or slower to recover from setbacks depends (at least in part) on pre-adversity resources and capabilities (see Bonanno et al., 2011; Galatzer-Levy et al., 2018 for reviews). For example, resilient organizations are those that (1) have more substantial resource endowments (Carmeli & Markman, 2011; Stephens et al., 2013) and pre-established capabilities, such as flexible decision making (Rahmandad & Repenning, 2016), innovation (Dewald & Bowen, 2010), and resourcing capabilities (Williams & Shepherd, 2016b); (2) can bring new resources to bear (Shepherd & Williams, 2014); and (3) deploy existing resources for new purposes (Bechky & Okhuysen, 2011). However, an adverse event can impact organizations over and above differences in resource and capability endowments. Indeed, in some cases, possessing larger resource endowments may inhibit an organization’s ability to rapidly respond to a challenge (Grimes, Williams, & Zhao, 2019) and discontinuous changes in its environment (Tripsas, 2009; Tripsas & Gavetti, 2000). Furthermore, while an adverse event can disrupt resource structures and institutional norms, it can also enhance the value of objects and resources previously undervalued and underutilized (e.g., community relationships, social capital, and human capital (Williams & Shepherd, 2018, 2021)). Thus, novel opportunities may emerge from an adverse event for those who can recognize and deploy new resource combinations to pursue opportunities. Indeed, research outside the work on resilience shows that organizations and their managers can have very different appraisals of the same event despite similar positions. For example, some may perceive an environmental signal as an opportunity and others as a threat (Dutton & Jackson, 1987; Jackson & Dutton, 1988) based on their regulatory focus (McMullen et al., 2009), entrepreneurial mindset (Kuratko et al., 2020), and firms’ strategic orientation (Wiklund & Shepherd, 2005). Therefore, an event recognized by all as adverse—for example, a global pandemic—may lead some to perceive opportunities and other threats. Beyond pre-crisis endowments, organizations can also achieve resilience through adaptive responses to an adverse event (Sutcliffe & Vogus, 2003; Williams et al., 2017). Organizations can be more resilient to an adverse event based on their cognitive and behavioral responses (Weick & Sutcliffe, 2011). Resilient cognitive responses include discerning an environmental change beyond simply surviving (Dewald & Bowen, 2010; Lengnick-Hall & Beck, 2005), adjusting through innovation (Dewald & Bowen, 2010), and implementing flexible (Rahmandad & Repenning, 2016) and shared (Weick, 1993) decision making. Resilient organizations respond to adversity behaviorally through enacting solutions (Lengnick-Hall & Beck, 2005; Rahmandad & Repenning, 2016), mobilizing and combining resources (Bechky & Okhuysen, 2011; Shepherd & Williams, 2014), and repurposing their identities (Powell & Baker, 2014). Overall, prior scholarship explores how organizations can prepare for a crisis and adapt in the moment to maintain functioning. However, this research does not address (as it was not its purpose) how actors might enhance functioning in response to a crisis. Furthermore, scholarship does not address differences in degrees of resilience as it usually treats organizational responses as either resilient to an adverse event or not (Ahmed et al., 2021; Sutcliffe & Vogus, 2003; Williams & Shepherd, 2016a). Post-adversity growth An alternative recovery outcome to bouncing back to the status quo is the notion of post-adversity growth, which is consistent with “aiming for ‘better’ rather than for ‘replacement’” when recovering from adversity (Shepherd & Williams, 2014: 976). This idea of “build[ing] back better” (Shepherd & Williams, 2014: 978) implies that in recovering from a disruptive crisis event, actors can grow from the experience and can “be changed, sometimes in radically good ways” (Calhoun & Tedeschi, 2014: IX). Consistent with the saying, “What doesn’t kill you makes you stronger,” there is substantial evidence that some individuals who experience a highly adverse event not only recover but grow from the experience (e.g., bereavement research (Tedeschi & Calhoun, 1995)). From this perspective, an adverse event serves as a “crucible” in which individuals “develop and deepen character” such that adversity serves as a training ground for their growth which may not have been possible in other contexts (Byrne et al., 2018: 255). Post-adversity growth research has been extended to employees experiencing adversity; employees can benefit from “transformative positive change that can occur as a result of a struggle with greater adversity” (Maitlis, 2020: 395). The notion of this form of growth is that in facing and recovering from an adverse event, an individual can begin to see him- or herself as stronger and more capable of coping with future adversity, see others with greater intimacy and belonging, and have a greater sense of purpose with different priorities (Maitlis, 2020). Beyond post-adversity growth, a related body of scholarship examines organizations thriving in the face of adversity (Alexander et al., 2021; Seville, 2016). For example, researchers have highlighted a trial-by-fire model (Bradley et al., 2011; Swaminathan, 1996), recognizing that organizations born under adverse conditions may benefit from adversity exposure if they survive. Similarly, other research recognizes that difficult circumstances can spur creative destruction in the form of technological changes (Eggers & Park, 2018; Giones et al., 2020), demonstrating that some organizations do not merely endure crises, but achieve new heights (Battisti et al., 2019; Morgan et al., 2020). For example, Alexander and colleagues (2021: 31) find that “some firms respond to traumatic events in ways that leave them fundamentally better across various dimensions, including financial and non-financial measures.” Despite these contributions, the literature on organizational post-adversity growth is still emerging. Similarly, advances in research on positive organizational scholarship (Spreitzer & Sutcliffe, 2007; Vera et al., 2021) speak to thriving in the face of adversity yet are not directly linked to resilience. We anticipate that significant insights can be achieved by challenging a dichotomized notion of resilience (i.e., resilient or not), allowing us to integrate resilience with the notion of in-adversity and post-adversity growth. Methods Research context To explore our research questions, we sought data that could be unusually revelatory (Eisenhardt & Graebner, 2007) to provide insights into how resilient organizations experience, interpret and respond to the same adverse event as opposed to other more traditionally explored phenomena (i.e., why some are resilient and others are not, or how organizations recover from a substantial disruption to their functioning, or whether one adverse event is more devastating than another). The focal adverse event is the onset of the COVID-19 pandemic. The adversity of the onset of the COVID-19 pandemic was devastating in its direct physical, social, and economic impact. At the societal level, this adverse event led to social distancing and sheltering to stop the spread of the virus. As a result, many mental-health problems arose from social disconnection (e.g., isolation and stress combined with drug availability led to a 30% increase in US drug overdoses in 2020 (McKay, 2021)), and as of this writing, more than 5.5 million people have died worldwide, and more than 900,000 have died in the USA (as of February 2022; Center for Disease Control and Prevention, 2022). From an economic perspective, the COVID-19 pandemic led to millions losing their jobs, a reduction of 2.2 million business owners in the United States from February 2020 to April 2020, and the devastation of many industries (e.g., hospitality and entertainment industries) (Craven et al., 2020; Fairlie, 2020). Within the context of the adversity generated by the COVID-19 pandemic, we sought data on resilient organizational responses that were transparently observable (see Eisenhardt, 1989). Identifying revelatory data on resilient organizations was possible for four reasons. First, the onset of the COVID-19 pandemic has a relatively definitive date of February/March 2020 (outside of China). At this time, it was widely recognized and broadcast as an adverse event that caused substantial suffering. Second, there has been extensive national coverage of the pandemic, efforts to constrain it, and the resulting suffering both have caused (Haroon & Rizvi, 2020). Third, organizations’ responses to the adverse event were largely observable as managers repeatedly communicated their assessments, planned responses, and the impact of the adversity on their organizations’ performance. Managers were aware of the adverse event and felt compelled to respond. Finally, the media recognized some organizations as functioning positively under adversity (i.e., as resilient organizations). Data collection Sample We targeted organizations for this study that explicitly and publicly sought to respond to the focal adverse event. Our primary sample comprises 34 interviews with founder-entrepreneurs of resilient organizations who were asked questions regarding their organizations’ actions amid the COVID-19 pandemic. Specifically, in the “How I Built Resilience” National Public Radio podcast series, Guy Roz identified 42 resilient organizations and interviewed their leaders. The podcast series selected founders (and their organizations) based on having built “resilience into their businesses during this very challenging year” (Roz). This mini-series of interviews is a variation of Roz’s regular programming (“How I Built This”), and data from that podcast series has proved fruitful in revealing important insights into entrepreneurs’ actions and decision making (Fisher et al., 2020). In considering data for our study, we eliminated interviews that fell outside the scope of our primary questions of interest—namely, outside how resilient organizations responded to the COVID-19 pandemic. Specifically, we eliminated interviews that focused mainly on the pre-pandemic creation and management of an organization (two interviews), interviews with domain experts providing advice to organizations facing adversity rather than representing themselves as entrepreneurs or managers of an organization (two interviews), and interviews with founders of social ventures (six interviews) (because these ventures typically have multiple logics, making direct comparisons with commercially orientated organizations more difficult (see Battilana & Lee, 2014)). After removing these eight interviews from the entire series, we had a sample of 34 interviews with founders of resilient organizations focused on responding to the adverse event associated with the COVID-19 pandemic. Having identified 34 resilient organizations as our primary sample, we also extensively searched for media and company reports on the 34 organizations from March to December 2020 to triangulate the findings from the interview data. We report the founders’ and organizations’ names because the interviews and secondary data are public. Using data generated and collected by others provided access to informants on the focal phenomenon, enabled us to avoid imposing researchers’ expectations on the respondents, and provided greater transparency for replicating our methods and findings. Indeed, collecting data in this way helped avoid common challenges with collecting interview data—it can sometimes be obtrusive, lack appropriate timing/context, and so forth (David & Sutton, 2004). Of course, the interviewer and the founders may still insert biases into the data collection. However, we sought to mitigate potential interview-specific biases by triangulating responses with the substantial secondary data we collected. Table 1 offers descriptive data about the interviewees, their organizations, and the form of organizational resilience.Table 1 Sample descriptive data Organization Nature of business Founded Est. sales 2019 Est. sales 2020 Interviewee (name/position) Resilience Airbnb Online marketplace for lodging 2008 $4.7B $3.4B Brian Chesky, co-founder Repurposing Bandcamp* Online means for artists to share and sell music 2008 Up 122% in 2020 vs. 2019 Ethan Diamond, co-founder Capitalizing Barre3 Online fitness teaching balance and empowerment 2008 $256 k Sadie Lincoln, co-founder Repurposing Bossy Cosmetics* Beauty company for women’s empowerment 2019 Unavailable; avoided shutdown Aishetu Dozie, founder Repurposing Bumble Online dating where women make first contact 2014 $240 M $337 M Whitney Wolfe, founder Realigning Canva Free-to-use online design platform 2013 $290 M $500 M Melanie Perkins, founder Capitalizing DreamBox Online software for mathematics education 2006 $21 M Jessie Woolley-Wilson, CEO Capitalizing EO Products Beauty and personal care based on natural inputs 1995 $2.6 M Susan Griffin Black, founder Repurposing Eventbrite Management of local events and ticketing 2006 $.32B $.10B Julia Hartz Repurposing Fluenz Online language-learning software 2007 Unavailable; avoided shutdown Sonia Gil, co-founder Repurposing Jeni’s Splendid Ice Creams Artisan ice cream and stores 2002 $42 M Jeni Britton Bauer, founder Repurposing Hello Sunshine* Media productions focused on celebrating women 2016 Repurposed, sold in 2021 for $900 million Sarah Harden, CEO Repurposing KiwiCo* Fun hands-on science projects for children 2011 New subscribers increased by 250%, sales up 650% from 2019–2020 Sandra Oh Lin, founder Capitalizing M.M. LaFleur* Women’s professional luxury apparel 2013 Avoided shutdown, entered relationship with Zappos in late 2020 Sarah LaFleur, founder Repurposing Life is Good Positive lifestyle clothing brand 1994 $52 M Bert and John Jacobs, co-founders Realigning Luke’s Lobster* Fresh and sustainable seafood 2009 Shifted online, now has locations in 10 US States, Japan, and Singapore Luke Holden and Ben Conniff, co-founders Realigning Lyft Online hiring of vehicles and food delivery 2012 $3.6B $2.4B John Zimmer, co-founder Repurposing Milk Bar* Chain of bakery restaurants 2008 Pivoted to increase sales by 113% Christina Tosi, founder Realigning Minibar and barmini* Michelin star restaurants 2014 Avoided permanent closure Jose Andres, founder Repurposing Peloton Exercise equipment, instruction, and workouts 2012 $714 M $1.8B John Foley, co-founder Capitalizing Q&A* Music distribution to empower artists 2019 Realigned, launched Innovation Labs (2020) for new products Troy Carter, co-founder Repurposing Rent the Runway Designer clothing rentals 2009 $257 M $158 M Jen Hyman, co-founder Repurposing Rinse* Laundry delivery service 2013 80% increase in sales from 2019–2020 Ajay Prakash and James Joun, co-founders Realigning Robinhood Online commission-free stock trading 2013 $278 M $959 M Vlad Tenev and Baiju Bhatt, co-founders Capitalizing Shopify Ecommerce software for starting or growing a business 2006 $1.6B $2.9B Toby Lutke, founder Capitalizing Single Thread Farms* Inn and restaurant 2016 Ongoing operations with 6 months booked out in advance Kyle Connaughton, owner Repurposing Slack Platform for chat rooms and messaging 2009 $401 M $630 Stewart Butterfield, co-founder Capitalizing Squire* Online platform for barbers to organize business 2016 Tripled its valuation from 2019–2020 (up to $250 million); Sales from 0—$10million (2019–2020) Songe LaRon, co-founder Repurposing Strava Platform for social fitness 2009 $60 M $72 M Mark Gainey and Michael Hovarth, co-founders Capitalizing Stemple Creek Ranch* Ranch for organic products and event venue 4th generation Avoided permanent closure Loren and Lisa Poncia, owners Realigning United Talent Agency representing entertainment professionals 1991 Grew, acquired Media Link for $125 million Jeremy Zimmer, co-founder Repurposing Wayfair Online platform for home products 2002 $9.1B $14.1B Naraj Shay and Steve Conine, co-founders Capitalizing Yelp Online business reviews and recommendations 2004 $1.0B $87 M Jeremy Stoppelman, founder Repurposing Zumba Exercise fitness program 1998 After pivot, experienced rapid growth Alberto Perlman, co-founder Realigning *Private company, sales increases and/or other data are from secondary data sources Interviews Our primary source of data was 34 interviews with founders. The interviews ranged from 14.26 to 85.73 min (mean = 24.17 min). We transcribed the audio of the interviews, which ranged from five single-spaced pages to 31 single-spaced pages (mean = 25.74 single-spaced pages per interview) for a total of 926 single-spaced pages of text. The purpose of the interviews was to talk with founders about two specific topics: “how they’re thinking creatively during such a disruptive time” and “how they’ve been building resilience into their businesses.” Near the end of the interviews, outside callers asked questions consistent with the two broad topics described above. The host asked similar questions to the founders. The audience questions represented a short period of the interview and were similar to the questions asked by the host and across organizations. Secondary data We searched Lexus Nexus for references for each organization in the New York Times from March 2020 to December 2020. We collected articles on the organizations’ experiences and responses to the adverse event. We chose the New York Times because it has designated business reporters and business articles. The scope is national (rather than regional). It provided ample articles to triangulate the interview data. Specifically, this search identified and included 57 articles and 248 single-spaced pages of text. We used these data to triangulate the findings from the interview data. Specifically, we reviewed the secondary data to verify claims by the interviewees provide additional context beyond statements made in the interviews, supplement gaps in the interviews, and (generally) triangulate the findings from our primary data source (Hampel et al., 2020). Data analysis We analyzed our data consistent with the principles of grounded theory (Locke, 2001). First, we relied on the insider/outsider approach when collecting and analyzing our data (Bartunek & Louis, 1996). The research team member that assembled, transcribed, and coded the interviews performed the insider role. The other member of the research team played the outsider role, pushing for clarification and elaboration (Crosina & Pratt, 2019; Strike & Rerup, 2016). For example, the insider presented the primary data source, and the outsider suggested other sources to triangulate the findings; the insider presented an emerging model, and the outsider made suggestions on its form and structuring, and the insider wrote up the findings, and the outsider pushed and probed the model, offered insights, and requested additional evidence. The insider and outsider then worked together to involve the literature and determine the model’s contributions to the literature. While our data analysis was iterative—moving from our data to emerging theoretical models and back again—our analysis followed three general steps. Specifically, we followed the three-stage process of (1) open coding, (2) axial coding, and (3) theoretical coding developed by Strauss and Corbin (1997), which has been used extensively in management scholarship (e.g., Crosina & Pratt, 2019; Grodal et al., 2021; Pratt et al., 2006). Open coding This initial data-analysis stage aimed to understand how the resilient organizations experienced, interpreted, and responded to the adverse event—the COVID-19 pandemic. Specifically, we identified and bracketed quotes to retain the informants’ perspectives in their own words (Williams & Murphy, 2021). In this early coding stage, we tried to keep the founders’ voices by coding nodes with labels consistent with how the interviewees described their experiences in the COVID-19 pandemic (consistent with Locke, 2001). In particular, we sought to identify common phrases and/or patterns (1) within each interview and then (2) between interviews. For example, open codes of statements included the following: “We have to adapt”; “[It] was a huge pivot for us”; “When you grow fast, you will get stretch marks”; “We were dealt a specific hand”; “Diversification helped keep us afloat”; “[This year] we’re making these tough decisions”; and “There is a need for human connection.” We went through this open coding stage multiple times, adjusting the labels to capture better the content chunks, group highly similar comments (e.g., “We grew from this experience” and “Perhaps surprisingly, this experience provided an opportunity to expand”), and ensure the open codes accurately adhered to the important information contained in the text. In reviewing common codes within and between interviews, we began noticing differences in how the informants responded to the adversity despite the interviews’ focus on resilience. This initial insight led us to revisit the data and explore nuance in how the informants experienced the adversity across a spectrum of responses. Axial coding Axial coding involves abstracting from open codes to move closer to grounded theoretical insights (Strauss & Corbin, 1997). In this analysis stage, we engaged axial coding to group similar open codes into clusters, adjust labels, and return to the data to verify and/or alter the labels until we ultimately settled on theoretically abstracted categories (see Crosina & Pratt, 2019). This abstraction from the open codes required labels that reflected movement toward more theory-based terms. Specific to our inquiry and building on the insight of different responses to the adversity identified in open coding, we began grouping our data based on the founders’ different perspectives. For example, we evaluated the specific codes capturing differences in founders’ decisions following the market impact, and we grouped those decisions as following “simple rules,” “values-based decisions,” and “focused on worst case” scenarios. This process drew us into theoretical conversations relevant to these types of entrepreneurial decision making, which helped us better position our emergent findings in theory. We repeated these processes with other concepts that emerged from the data and began arranging our findings into trajectories. We found three separate groups of resilient organizations distinguished by differences in how they experienced the adversity, which led to differences in their response paths. Some organizations were resilient to a big drop in market demand, some were resilient to a slight dip in market demand, and others to a positive jump in market demand. We compared and contrasted differences in various codes (as described above) across the three groups of resilient organizations to inductively explore if these patterns were represented throughout our sample. Consistent with Crosina and Pratt (2019), we then examined patterns across the groups to explore our axial coding. For example, we used “shifting emphasis” to capture how the founders emphasized different aspects of their current business, accelerated transitions, and exercised pre-existing options; we used “pivoting” to capture how the organizations made substantial changes in strategic direction; we used “incremental adjustments” to capture how the organizations made incremental adjustments to capitalize on opportunities; and so on. As with the decision-making related axial codes described previously, we inductively developed these concepts by (1) evaluating first order codes, (2) abstracting those codes into broader categories, and then (3) considering relevant literature that could potentially frame and/or inform our findings (e.g., literature on strategic change, entrepreneurial resourcefulness, and so forth) (Davis et al., 2009; Fisher et al., 2020; Williams et al., 2021). We continued to notice differences across codes for the organizations based on their resilient responses to the adverse event. At this point, we began to theorize on different responses through the lens of the literature on responses to adversity—which we began to call different response paths to organizational resilience. We found two response paths consistent with the notion of resilience maintaining positive functioning in the face of adversity (after a short, unsettling period (see Bonanno, 2004; Bonanno et al., 2011))—repurposing resilience (n = 17) and realigning resilience (n = 7). We also found organizations that experienced increased positive functioning, which we labeled capitalizing resilience (n = 10). The differences we noted across these three trajectories served as the impetus for splitting our sample into three sub-samples. We then compared and contrasted these sub-samples (outlined in our theoretical coding section and defined/elaborated on in our findings section). For our coding, for example, the capitalizing versus realigning versus repurposing resilient organizations differed on axial codes in, respectively, (1) “needs generated by the adverse event” versus “needs for pre-adversity products” versus “demand substantially reduced” (2) “simple rules” versus “value-based decisions” versus focused “worst-case scenario,” (3) “incrementally adjusting” versus “measured adjusting” versus “pivoting—wholesale adjusting,” (4) “rapidly scaling” versus “reimagining and renewing” versus “hustling.” Theoretical coding In this last stage of coding the data, we began configuring the axial codes into aggregate dimensions as a basis for inducting a larger theoretical story (Charmaz, 2014; Crosina & Pratt, 2019). As alluded to above, it became clear that the adverse event impacted the sample of resilient organizations differently, which led to the three pathways reflecting different resilient responses and outcomes (from the same adverse event). As illustrated in Fig. 1, we aggregated the axial codes to reflect theoretical dimensions. We further abstracted our axial codes into theoretical concepts that we incorporated into a dynamic, grounded theoretical model. Specifically, the theoretical dimension of “organizational functioning” captured the capitalizing, realigning, and repurposing of resilient organizations; “market reaction to adverse events” captured the increase in demand generated by the adverse event, demand for pre-adversity products, and demand substantially reduced; “decision making” captured simple rules, values-based decisions, and worst-case scenario; “strategic actions” captured adjusting incrementally, shifting emphasis, and pivoting; “organizational capabilities” captured capabilities for communication and coordination, varied capabilities, and building new capabilities; and “operational activities” captured scaling, repurposing, and hustling.Fig. 1 Data structure Having identified an initial set of theoretical concepts, we systematically explored similarities and differences across the three pathways. As we proceeded, we also iterated between our aggregated findings and extant theory to consider if/how our data was theoretically revelatory. In systematically comparing these three pathways, we noted that in decision making, the difference between the capitalizing resilient organizations' simple rules did not vary greatly from the realigning resilient organizations’ value-based decisions. However, the inputs and outputs of their decision making varied considerably, as detailed below. We then refined the model by exploring potential mismatches between the emerging model and the data and vice versa. We also analyzed the newspaper articles (by coding chunks of text consistent with the codes generated from the interview data) to triangulate the emerging findings. After many iterations, we eventually settled on a grounded theoretical model that best represents the data. We report and display this model at the end of the findings section. Findings Our findings begin with the adverse event that all the organizations in our sample experienced. However, after the onset of the adversity, we began seeing differences across our sample that emerged and persisted based on four primary factors: (1) market reaction, (2) problem framing and decision making, (3) strategic change, and (4) operational activities. These factors constitute the primary comparative means by which we communicate our findings. We compare and contrast the three resilience response paths (capitalizing, realigning, and repurposing) that emerged from our findings across these four factors. By capitalizing resilience we refer to the trajectory of the organizations that took advantage of potential opportunities for growth due to the market conditions. Realigning resilience refers to the trajectory of the organizations that redeployed existing resources to better align with the changed market conditions. Redeveloping resilience refers to the trajectory of the organizations that completely restructured their resources, capabilities, and activities to create market opportunities that would allow for ongoing functioning. Our findings reveal that patterned differences across these factors influenced the organizations’ paths to resilience. We discuss our findings by beginning with the common exposure to the adverse event. Adverse event All interviewees acknowledged the adversity that resulted from the COVID-19 pandemic—for their organizations, society at large, and the economy. Indeed, specific to our sample, the COVID-19 pandemic substantially impacted the US economy. The following New York Times excerpt well captures the COVID-19 pandemic’s impact:Not since the attacks of Sept. 11, 2001, has a crisis enveloped so much of the economy so quickly. Broadway is dark. The college basketball tournaments are canceled, and professional sports are on indefinite hold. Conferences, concerts, and St. Patrick’s Day parades have been called off or postponed. Even Disneyland—which stayed open through a recession a decade ago that wiped out millions of American jobs and trillions of dollars in wealth—is shuttered. This hits the heart of the economy, and it hits the economy on all sides,” said Diane Swonk, chief economist at Grant Thornton (Casselman et al., 2020). Regardless of the ultimate trajectory, all sample organizations experienced the event as adverse and changing market demand for their primary products/services. For example, Vlad Tenev and Baiju Bhatt (co-founders, Robinhood; capitalizing organization) explained, “[In February 2020] the US had just gone into lockdown and the stock market cratered.” Loren and Lisa Poncia (co-owners, Stemple Creek Ranch; realigning organization) recalled the arrival of the crisis in this way:Everything starts to shut down. . . . It was a very scary time for all of us; it was definitely very tumultuous. . . . our most immediate concern was that our team, our staff, was not going to be able to work. We were going to get sick, or we weren’t going to be able to physically leave our homes to go to the workplace. Alberto Perlman (co-founder, Zumba; realigning organization) noted that “many gyms and fitness studios are closed, leaving Zumba instructors without a place to teach,” which was a direct threat to his organization’s survival. While the organizations we studied all experienced adversity associated with the COVID-19 pandemic and faced some disruption to functioning, they all quickly returned to positive functioning—consistent with a resilience response (Bonanno, 2004; Williams et al., 2017)—and continued to generate revenue throughout the crisis (albeit through different paths). These resilient responses stood in contrast to other firms, such as Hertz rental cars, that lost operational functioning (i.e., sought to reorganize under Chapter 11 bankruptcy) and then entered a period of recovery that is ongoing as of this writing (Paukert, 2020). Notably, while we observed that all of the organizations we studied maintained functioning, there were apparent differences in the specific impact of the adverse event on each organization and the organizations’ pathways to achieving resilience. Indeed, after the initial shock of the adverse event subsided, the organizations in our sample faced different market reactions to the adverse event based on their industries, which represented the “hands they were dealt” (consistent with the paper’s opening quote). We then explain differences in their resilient responses to market conditions—how they played the hands they were dealt. Market reactions to the adverse event (1 to 2 months after the onset of the adversity) Although the pandemic is an adverse event and was recognized as such by the founders of our sample organizations, the pandemic impacted their industries differently. Some industries (e.g., hospitality, travel) experienced sudden losses, whereas others (e.g., online personal fitness, information) experienced sudden increases in demand (Klein & Smith, 2021). Unsurprisingly, we found that differences in the impact of the adverse event across industries had a different impact on the organizations’ primary markets and, as a result, required different resilience responses to enable ongoing functioning (see Table 1). Organizations resilient to a substantial reduction in market demand The repurposing resilient organizations experienced a big drop in market demand for their products and services. While, at least initially, the drop in demand was so significant that many of these founders were worried about whether their organizations would survive, these organizations maintained organizational functioning. For example, when Sarah Harden (CEO, Hello Sunshine—a media production company focused on celebrating women) was asked, “You’re not filming anything right now,” she responded, “That’s correct,” as essentially all business operations ground to a halt. Similarly, Jeremy Stoppelman (founder, Yelp—a company that hosts online business reviews and recommendations) explained how a lot of his company’s business is with restaurants, noting that “this industry has just been hammered, unlike any other industry” and “maybe [sales] are not zero, but it is going to zero pretty damn quickly.” Taken together, the repurposing resilient organizations largely faced market conditions that resulted in a substantial drop in nearly every facet of their business, thus precipitating the need for significant corrective actions to maintain functioning. Organizations resilient to a marginal reduction in market demand The realigning resilient organizations initially faced diminished demand for their products and services, although less than the demand drop for the repurposing resilient organizations. These organizations were able to find a way to overcome this dip in demand. Ajay Prakash and James Joun (co-founders, Rinse) explained the impact of the adverse event on demand for their products and services: “So, dry cleaning has certainly taken a hit. You have less people going to the office; less people traveling; weddings and graduations and formal events aren’t happening.” Similarly, Bert and John Jacobs (co-founders, Life is Good—a positive lifestyle clothing brand) explained,By and large, we knew that consumers want things closer to market, want greater choice, etc. And we were trying to migrate in that direction. . . . And I think in particular in these really difficult times, we also learn how much people need optimism, need uplifting messages. . . . Our point of difference is seeing the world through an optimistic lens and sharing those ideas—how an optimist views the world. Organizations resilient to a substantial increase in market demand After the initial shock of the adverse event, the capitalizing resilient organizations found that it generated greater demand for their products and services or adjacent products or services. Although these founders acknowledged their organizations’ luck in occupying a market position where demand increased, they faced significant obstacles in responding to opportunities generated by the adverse event (as we will explain later). For example, the adverse event led Ethan Diamond (founder, Bandcamp—a company that hosts music-label and artist content and allows those actors to control pricing, etc.) to pause and consider his company’s industry impact: “The pandemic hit; the shutdown happened. We realized, okay, many artists are losing a huge part of their income. This is our community. What can we do to help?” Indeed, artists could no longer tour and hold live events, a mainstay for promoting music. However, Bandcamp’s decisions to offer artists a platform to hold live online events and sell their music soon led to demand for their services growing beyond their capacity to serve. Indeed, the theme of a positive jump in demand was common for the capitalizing resilient organizations: Peloton (home-based fitness) saw a “huge surge in demand,” Canva (online design tool) grew rapidly, Shopify (online payment processor) experienced a “spike in new customers,” and Wayfair (online furniture retailer) experienced “unexpected success during the economic crisis.” In explaining the jump in demand, many of the founders of the capitalizing resilient organizations noted that the adverse event generated a greater need for people to remain connected. Their organizations’ products and services helped address this newer or expanded need. John Foley (founder, Peloton—a company that provides exercise equipment, instruction, and workouts) explained,We’re bringing connection, we’re helping people relate, and we’re understanding, and we’re supportive, and we’re there for them in a wild way. It feels like Peloton was built for this moment of helping people connect virtually. It’s a really beautiful thing that we’ve experienced. We’re all learning about new ways to connect and meaningful ways to connect. (Emphasis added) Problem framing and decision making While the market conditions the organizations in our sample faced differed following the onset of the adverse event, these differences alone did not determine the entire trajectory of an organization’s resilience response path. Indeed, faced with the initial experiences of the adverse event and its impact on their organizations’ primary markets, the founders framed the problems their organizations faced differently, which influenced their decision making on how to respond. This framing and decision making varied across the categories of organizations, which played an essential role in shaping their overarching response paths (see Table 2 for illustrative quotations).Table 2 Decision making for responding Capitalizing resilience Simple rules Realigning resilience Values based Repurposing resilience Worst-case scenario And if one of the incentives here is not just the health, and see if you have our employees, but kind of being good citizens and good stewards …. We should do it as quickly as possible. (Founder, Slack) It was really important that we set up, sort of, our guiding principles. (Founder, Canvas) I think the entire company has incredible clarity of mission right now, again, about what we set out to do. But exactly how we do this [is] really left to all these parts of a company. We love to be loosely coupled, but loosely coupled only really works when we come together and base our decisions on the same fundamentals. (Founder, Shopify) Our focus in the beginning was really we need to make sure that our people are okay. All the other considerations, they have to come after that. And that was where we focused initially. So in some sense, you have a single purpose. You do that, you do that as best you can. (Founder, Strava) “There were seven execs,” Butterfield [founder, Slack] recalls, “and everyone spoke between 30 and 90 s.'' Each executive expressed gratitude to staff, then briefly explained his or her most important priorities— “and that was it.” The entire thing was over in 21 min. (Griffith and Hirsch, December 1, 2020) It’s no secret that for all but a rarefied few musicians, record sales alone can no longer pay the bills. Back in March, when tour cancellations wiped out many performers' livelihoods overnight, Bandcamp took action. This week, the music platform will continue its new custom of waiving its revenue share on purchases made the first Friday of every month, so fans can put more money directly into artists' pockets. (Burke, September 4, 2020) I think we were good to act quickly in this business. I mean, not just because my name is at stake and my family is part of it [the business]. There is no difference or delineation between my personal [and] business life. So when you’re faced with ultimately making that critical decision to save a business, it affects your family and friends in major ways.... We got super small [so] that we got aligned around some strategic initiatives pretty quickly. (Founder, Luke’s Lobster) So we said we have to do three things. One, the most important thing, how do we continue to help instructors generate income. Two, how do we deliver education virtually for people? New people want to become instructors or our existing instructors who need further education, especially if they’re transitioning to virtual. And three, how do we keep our promise to make the world happy and healthy? (Founder, Zumba) I think fundamentally it starts with a question of, like, “Are you in a good place to make those decisions?” And what I mean by that is it’s incredibly stressful. I’m sure there isn’t a single CEO out there who isn’t up at 4:00 a.m. thinking, like, “Oh, God, what am I going to do about that?” But the most important thing is kind of keeping your wits about you. (Founder, LeFleur) What would we do? How do we survive? Is there a freeze?... And it’s a nuclear winter type of situation. Fortunately, the world did start to restabilize. (Founder, Yelp) We ran the worst-case scenarios, the medium-case scenarios, and the best-case scenarios and then made the decision that raising the debt was kind of a no-regrets move. But then... preserving the cash... on hand, making decisions about expenses... we needed to tighten up. (Founder, Lyft) So this goes to show you can never really know, but it’s always safe to kind of assume the worst case and be prepared for the worst case, which we were prepared to go to zero revenue for over 12 months. (Founder, Squire) In May, Airbnb announced that it would go “back to our roots” by focusing on “everyday people who host their homes.” (Griffith, February 21, 2021) Repurposing resilient organizations The repurposing resilient organizations framed the situation as a worst-case scenario and existential threat and employed survival rules to guide decision-making processes. A worst-case scenario refers to a situation in which individuals believe the circumstances exceed their ability to control/manage the challenges, and seemingly everything that could go wrong goes wrong (Fischbacher-Smith, 2010). For example, Songe LaRon (co-founder, Squire—an online platform for barbers) described the adversity as likely to ruin his business: “It’s always safe to kind of assume the worst case and be prepared for the worst case, which we were prepared to go to zero revenue for over 12 months [to survive].” Similarly, Jerremy Stoppleman (founder, Yelp) described the situation as “a nuclear winter type of situation.” With the framing that their businesses faced the most severe threat to survival, these founders sought to make decisions that “matched the moment.” This meant enacting decisions as the businesses entered “unknown territory.” Repurposing founders believed there were no decision-making guides for such an existential threat and that they had exceeded their risk models. For example, Brian Chesky (co-founder, Airbnb) noted that “there is no playbook” for operating in the pandemic context—all goals had to be set aside to survive. He explained,We’re not going to be the kind of company that will be destroyed by this. So we’re going to obviously try to take care of each of our stakeholders. And when we got to the employees, we basically had exhausted options. Having raised $2,000,000,000, we came to the conclusion that we would have to do layoffs when we confronted the hard truth. … we did not know when travel would return. Nobody did. And the second thing we knew is that when travel would return, it would look fundamentally different than the travel before the pandemic. And so our business would have to look different, and we’d have to change the shape of our business and what we focused on. For these organizations, business survival entailed concerted efforts to conserve cash and treat employees with respect, especially those they felt they had to lay off. The idea was to “get through” this period and begin rebuilding. For example, Christina Tosi (founder, Milk Bar—a chain of bakery restaurants) reflected on this initial stage of responding to adversity as a.scary game to play, and that’s reality. And so you have to just track it because you can’t control it and you can’t get stuck in it. And there’s no rearview mirroring. You cannot turn, look back. There’s only forward. . . . So let’s just take one step forward every day. Realigning resilient organizations The realigning resilient organizations framed the problem as difficult but endurable and relied on values to guide their decision-making. For example, Alberto Pearlman (co-founder, Zumba—an exercise fitness program) described the pandemic and its consequences this way: “It’s tough [on our Zumba gym owners], and we’ve been trying to help them [through it].” Interestingly, framing the problem in this way led the realigning resilient organizations to emphasize how they would make their decisions for organizational changes based on core values. For example, Bert and John Jacobs (co-founders, Life is Good) described their approach this way:Our mission is to spread the power of optimism—we’re so lucky to have that—and these 10 values we call the Life is Good superpowers. Things like gratitude; that is so huge right now. We’re hearing it from our customers. . . . We hear this from our employees. . . . But we’re fortunate that the foundation of our company is . . . one thing we believe is timeless and powerful and that is optimism. . . . We had to adjust. But the foundational values are rock solid. . . . But values in a lot of companies, I feel like, is [sic] a dusty couple sheets of paper that’s tucked away. Our superpowers are something we talk about daily. Our employees embody these values—gratitude, love, authenticity, creativity. And we live for these things, and we live for spreading them out to the world. As a foundation for decision making, key principles provided some sense of control and agency in a time of chaos. Ajay Prakash and James Joun (co-founders, Rinse—a laundry delivery service) discussed how values influenced their decision making in the current ambiguous and challenging environment. Ajay explained, “So the importance of having core values—the importance of having guiding principles so that when you get into situations like this where things can get blurry, you can stay rock solid and focus on the goal—I think is a really important takeaway.” Capitalizing resilient organizations The capitalizing organizations framed their problems as potential opportunities and used simple rules to guide decisions. While crises inevitably pose challenges, they also generate potential opportunities—especially opportunities to help people (Williams & Shepherd, 2016a). The capitalizing resilient organizations framed the crisis as introducing opportunities for incredible growth. For example, Ethan Diamond (founder, Bandcamp) described the potential of opportunities in the current environment, noting that before the pandemic, “We weren't thinking about entering that at all [new independent venues for live music events]. And in retrospect, it was kind of crazy that we weren’t. It was conceived, designed, and built in a very, very short period of time. We moved several people off of other projects to get that done.” To capitalize on the emergent opportunities, these organizations employed simple rules for decision making, which enabled them to avoid becoming bogged down and increased the speed of their decisions. Simple rules refer to a strategy that emphasizes pursuing opportunities, jumping into the confusion during market transitions, and orientating businesses toward growth (Davis et al., 2009; Eisenhardt & Sull, 2001). For example, Melanie Perkins (founder, Canva) identified opportunities to achieve high growth. She explained how the pursuit of these opportunities had to be guided by what she described as three decision-making pillars:[Pillar 1] The first one was our safety, and well-being is the number one and most important thing at all times. That sort of meant that we, [in] early March, had started working from home prior to the government recommendation. And then, [Pillar 2] making sure we’re supporting our community. And then, [Pillar 3] rallying together and growing. And those have sort of been the three pillars that we’ve made all of the decisions for our company based upon in the months gone. While our informants explicitly described how they used simple rules to make organizational decisions, sometimes the simple rules and decision making appeared similar to the realigning organizations’ reliance on “fundamentals” (Shopify), a “single purpose” (Strava), and a “clarity of mission” (Shopify). Further, some of the capitalizing organizations’ initial decision making resembled that of the repurposing organizations before they transitioned to relying on simple rules. For example, some of the resilient organizations’ initial decisions were to “pull back and remain conservative” (KiwiCo), “make sure that our people are okay” (Strava), and “raise money... [that] in hindsight, we didn’t need” (Wayfair). However, we still labeled these resilient organizations as “capitalizing” because their initial responses of seeing the event as a worst-case scenario or one that simply had to be endured soon faded, and their leaders shifted rapidly to decision making based on simple rules (some of the simple rules were guided by values/mission) to exploit opportunities arising from a positive jump in market demand. For example, Sandra Oh Lin (founder, KiwiCo) explained how initially (the first one to two weeks), “we definitely became more conservative. So very quickly, we decided to basically pull back or remain conservative on marketing spend. We were looking at things like hiring and figuring out what we wanted to do. So we held [paused] on hiring.” She continued and noted, however, that after a few weeks of “tracking the business... we actually started to see pretty quickly a pretty decent uptick in the business” and thus changed the company’s response. Strategic change response The initial framing and decision-making scope described above ultimately guided the organizations’ strategic change initiatives. Strategic change is a deviation in how an organization allocates resource dimensions that are believed critical to performance (adapted from Zhang & Rajagopalan, 2010). In response to their situations, the organizations implemented strategic change initiatives to identify and deploy available resources and capabilities as part of their resilient responses to their changing external environments. The desired strategic change and the capabilities for enacting such change varied across the categories of resilient organizations (see Table 3 for additional representative quotations), to which we now turn.Table 3 Responding through strategic actions Capitalizing resilience Incremental adjustments Realigning resilience Shifting emphasis Repurposing resilience Pivots I think my advice and what has served us really, really well has been aligning the business model with the community that we’re here to serve. (Founder, Bandcamp) In 2010, we started to move towards the B2B model, but I didn’t shut down the parent channel, the consumer channel. We knew that they were teachers there and administrators there in the parent channel. And we thought that if we could win their confidence, it would help the institutional side of the business. (Founder, DreamBox) Peloton stopped filming live classes in early April after an employee at its New York studio tested positive for the coronavirus. But by the end of the month, it was streaming live classes again. The first one happened on April 22 from the apartment of Robin Arzón, Peloton’s head instructor. More than 23,000 customers logged in and rode along with her, issuing virtual high fives and climbing a digital leader board. “When things are uncertain, we adapt,” Ms. Arzón wrote on Instagram, alongside a photo of herself surrounded by production equipment and electrical cords in her apartment. (Griffith, May 7, 2020) Harley Finkelstein, Shopify’s president, said Google and Shopify were developing new ways for merchants to sell through Google services, such as experiments to allow customers to buy items directly on YouTube and to display what products stores are carrying in Google Maps. (Wakabayashi, 2021) The idea from the beginning, not just with COVID, but what we were trying to do is maintain the company’s value system but change the business model. Founder, Life is Good) It’s about adaptation. We listen closely to our customers. It’s a dialogue … You have a business, you know, the world’s changing. You can’t have the same business. (Founder, Life is Good) All we knew is we need to find a way to keep buying seafood and getting seafood to people who want it. So it was actually an amazing experience. We had one of our teammates... suddenly have to start researching how to build an ecommerce business. (Founder, Luke’s Lobster) The first thing we did was we allowed our instructors to start teaching online. They started teaching on Zoom, but parallel to that, we started developing our own platform, and it’s called Zen Studio. (Founder, Zumba) We had very fortunately been ahead of the curve with an app [for] video chatting that was a feature that historically had moderate to low use.... Remarkably, the usage just went through the roof. (Founder, Bumble) A collaboration to encourage their use, between the Maine Coast Fishermen's Association, a trade group; Gulf of Maine Sashimi, a high-end processor; Island Institute, a nonprofit Maine community group; and Luke’s Lobster, a restaurant chain; are making the fish [hake] available nationwide, flash-frozen, at Luke’s online store. Luke Holden, an owner of Luke’s Lobster, is serving the fish at his flagship restaurant in Portland, Maine, but said his other locations were too small to allow for the preparation.... They’re selling each fish in two one-pound packages, $60 for hake, $55 for monkfish and $18 shipping. (Fabricant, February 24, 2021) EO makes a whole line of body, skin, and hair care products, but since the COVID-19 crisis, we’ve pivoted to pretty much only making hand sanitizer and hand soap. (Interviewer, EO Products) And I’m like, “Look, there’s nothing to sell, guys [customers], but can we chat? Can we talk?” And it became this whole community discussion.... And so that just kept me busy. (Founder, Boozy Cosmetics) I think we’ve never seen ourselves as a workwear brand [clothes]. We’ve always seen ourselves as a brand for working women.... We launched a channel.... And then customers are actually uploading and sharing different opportunities that have come their way and using it as a tool to just help other people find jobs. (Founder, LeFleur) You know, when we started closing stores and we started to... make videos.... People are going to be at home and baking and cooking and curious more than ever about food. So let’s show up for them. And we filmed all this stuff. (Founder, Milk Bar) We’ve got a farm full of produce. I’ve got a restaurant full of food. You know, I’ve got a team that just wants to cook. How about this idea? I'll start reaching out to friends of the restaurant and wineries and investors and great guests that we have and see if they can start funding. So I’m a family man and we’ll start preparing food and I’ll put everyone to work. We’ll start cooking. (Founder, Single Thread Farms) “In the absence of our ability to bring people together for in-person experiences, we moved fast to help creators take their experiences online,” said Julia Hartz, a founder and the chief executive of Eventbrite. (Brown, December 31, 2020) Repurposing resilient organizations The repurposing organizations sought to address what they saw as a worst-case scenario by pivoting, or wholesale adjusting to significantly alter their organizations’ strategic direction to survive the sudden collapse in market demand. Given the big dip in market demand, they changed by pivoting to find a new path through adversity. A pivot refers to a “structured course correction designed to test a new fundamental hypothesis about the product, strategy, and engine of growth” (Ries, 2011: 149; e.g., Grimes, 2018; Hampel, Tracey, and Weber, 2019; Morgan et al., 2020). For most, their pivots were so substantial that the founders saw the situation as akin to starting a new organization altogether. For example, Sonia Gil (co-founder, Fluenz) described the company’s change in strategy:In March, we got to start a company all over again, but we got 30 days. What do we do? Website?. . It was clear that the way to do it was we had to pivot and go online. . . . How do we pivot the face-to-face experiences where people definitely expect much more than just the language learning, right? It’s about a cultural experience. It’s about feeling taken care of. How do we translate what we have there into this screen? And thankfully, throughout the years that we’ve done the in-person immersion, we had been doing some online coaching with people that had already been in the immersion to continue. So we already had a little bit of knowledge in terms of the format. While their pivots reflected a substantial risk, the repurposing organizations felt they had little to lose in finding a new path when considering the worst-case scenario. For example, Sadie Lincoln (founder, Barre3—an online fitness company that teaches balance and empowerment) reflected,We had to let go of that beautiful production. And I remember distinctly the team, we kind of ask ourselves, What are we afraid of, like, go try. Let’s do this. And when we gave all of our owners and ourselves that permission to be messy, to fail, and then pick ourselves back up and ultimately triumph. … And now it’s done significantly better because so many people are working out at home. They’re subscribing to that. As Sadie Lincoln explained, pivoting was the only option for Barre3 to survive, and the company planned to pivot and pivot until hitting on a sustainable idea. Realigning resilient organizations The realigning organizations responded through strategic change that involved measured adjusting or carefully shifting emphases in their diversification strategy to accommodate fluctuations in demand and capture potential opportunities. Rather than pivoting wholesale, the realigning organizations resourcefully evaluated their portfolios of resources and diverse interests to figure out what could be brought to bear (Williams et al., 2021) and redeployed toward new ends in response to their experienced dip in market demand. Therefore, their strategic activities involved a shift in emphasis—a redeployment of resources (financial, human, managerial)—to higher-demand areas that showed promise. For example, Bert and John Jacobs (co-founders, Life is Good) recognized that they could use this disruption to change their emphasis from an archaic set of processes to better align to new growth opportunities. Bert said,The tail was wagging the dog where the wholesale business and this long supply chain window was kind of ruling our company. And we already knew that that was an archaic model. … And that in some ways or maybe in every way, the COVID crisis kind of was your opportunity to do that. I fast-forwarded everything. … we’re one of those fortunate businesses where COVID did us a favor. It really moved us along. Although some realigning organizations described their strategic actions as a pivot, we differentiate a “measured adjusting” strategic change response from a pivot in that these organizations did not launch entirely novel activities. Instead, they had some prior engagement in their new activities and were now simply emphasizing those activities while decreasing their emphasis on others. For instance, in describing their strategic action, Luke Holden and Ben Conniff (co-founders, Luke’s Lobster) noted the following:We’ve had to pivot from selling to other restaurants and food service and casinos and cruise lines and build that grocery branded business that we had. We had to get from big, unbranded commodity packs and start producing grocery branded freezer and refresh container-type packages. So that was a huge pivot for us. Similarly, Alberto Perlman (founder, Zumba) noted that during the crisis, “surprisingly, our clothing business is doing very well. People are buying fitness clothing to work out at home, and we were able to manage it.” This shift in emphasis relied on the organization’s diverse capabilities to accelerate the transition to performing this new strategy. Capitalizing resilient organizations The capitalizing organizations maintained core business operations and took strategic action by rapidly and incrementally adjusting the production and sales of existing products/services to capture value from the sudden surge in demand. These organizations looked to effectively capitalize on the positive surge in market demand for their products/services. For example, John Foley (founder, Peloton) described how changes his company made focused on enhancing the performance of their current products and services, such as changes to the delivery service and product setup:We found a lot of creative solutions on how to deliver bikes. … And we’ve created new tools online to help you do what our delivery folks would have done had they delivered it and spent the half hour setting it up. And now it’s more of a self-service model … And it’s working. We found some good solutions. Naraj Shay and Steve Conine (co-founders, Wayfair—an online platform for home products) sought to quickly implement changes to capture the rise in demand for home furnishings during the pandemic. They explained,I do think [during] this period of time [facing the crisis], we noticed that even though you’re big, you can still change quickly. And so, I think we have a team that can react dynamically, and we have a very entrepreneurial culture still. And I think innovation favors entrepreneurs during a time of change. . . . It’s something that we do well as a company. Navigating, regardless of kind of what the future looks like. Operational enactment The adversity created challenges for the resilient organizations in determining how they needed to change and how they could then implement that change. Indeed, as is common in the aftermath of sudden onset challenges, resilient organizations faced significant operational difficulties due to a rapid switch to remote work, supply chain disruptions, and surrounding restrictions and lockdowns. Our data revealed that the resilient organizations differed in their operational enactment processes in response to their market demand situations and strategic change objectives. We now explain these differences (see Table 4 for additional illustrative quotations).Table 4 Responding through operational activities Capitalizing resilience Stretching and scaling Realigning resilience Rethinking and reinventing Repurposing resilience Experimenting and repurposing I think it’s spiked at 10 or 11 weeks [delayed product delivery] in some markets. And I think we’re down to six or seven weeks in most markets at this point. And as we continue to build capacity in our manufacturing, pipeline, and supply chain, we’re able to meet the demand a little bit faster. So it’s coming down. (Founder, Peloton) And you can imagine, kind of, the acceleration of the business. (Founder, KiwiCo) So we’ve definitely had different challenges associated with meeting the demand. I think the great thing is that our team has been incredibly responsive and making sure that we were shoring up our supply chain, putting in the appropriate orders to make sure that we had the inventory available.... And so we had to actually scale that up pretty significantly. (Founder, KiwiCo) And I think there was a lot going on. We were trying to keep our systems up amidst being number one on the app store.... We were raising the capital to make sure we could relax the requirements. (Founder, Robinhood) But the volume has grown dramatically. And as you can imagine, the delays and the carrier networks just create even more calls. So there’s a lot of challenges.... So there’s a lot of supply chain challenges. And so we started working on that right away.... You do see out-of-stock rates recovering [and] transportation getting better, but it doesn’t happen overnight. (Founder, Wayfair) Peloton is now transporting some of its bikes by plane to avoid congested ports, a move that is significantly more expensive. In late December it paid $420 million to acquire Precor, a fitness manufacturer based in the United States, which will allow Peloton to begin producing bikes stateside in the second half of the year. (Maheshwari and Griffith, January 17, 2021) Hey, now I’m teaching online and can take my class virtually. And every week, we launch improvements to the platform. So we added that to the platform so students can chat while they’re taking the class. We added emojis. We added things to the paywall so that instructors could take payment... every week. We’re launching a new tech at a pace that our technology team had never done so before. And I’m so proud of them because they really took it to the next level.... It felt like we were starting again. (Founder, Zumba) For other farmers and ranchers, the onslaught of interest from home cooks has outstripped their ability to meet demand. Loren and Lisa Poncia run Stemple Creek Ranch in Marin County, Calif., where about 900 cattle and 500 sheep feed on organic-certified pasture. Sales to restaurants made up 11 percent of their revenue. They lost most of it. They are still shipping to a handful of butchers and grocers in California, but online orders from home cooks have risen so fast it’s been a scramble to keep up. They spend their days and nights packing meat with dry ice and trying to navigate the strain on their system, which includes overwhelmed processors who cut and wrap their beef. “It’s one thing to send out a whole 20-pound rib roast to a restaurant, but now it needs to get cut into pound-and-a-half rib-eyes, and they just don’t have the capacity,” Ms. Poncia said. (Severson, April 10, 2020) Then suddenly we noticed that there were nurses, EMTs, and doctors, and they were going into hot zones and needed places to stay. Hosts are telling us, “Hey, we can host these people?” And we created this program called Frontline Stays to provide housing for frontline workers. And we had more than a 100,000 hosts list their homes for a discount. We waive fees. (Founder, Airbnb) All the way down the chain, the fishermen, the farmer, everyone who’s involved with this is being deeply impacted. So we’re really trying to support our local farms and our local producers, but things that you take for granted, it’s difficult to get. We have to be flexible. We have to be sort of like nimble with that planning. (Founder, Single Thread Farms) I always try and be thoughtful about being super open minded, and so I’m grateful for some of the small wins despite the really big hits. (Founder, Milk Bar) In late March, Mr. Chesky [Airbnb] apologized to hosts for how the decision had been communicated. “We have heard from you, and we know we could have been better partners,” he said in a video. The company set up a $250 million fund to cover some of the cancellation costs and a $10 million relief fund. (Griffith, February 21, 2021) [Some] may have a hard time feeding their people, but if we are involved, we will not have a problem feeding a village. Because we know where the food is,... water is,... the generators are,... the refrigeration is.... This theory of mine is proving itself time over time. (Saltstein, June 29, 2020) Repurposing resilient organizations In their desperate effort to implement various pivots, the repurposing resilient organizations relied on hustling to find and refine a path for survival continuously. Hustling refers to “urgent, unorthodox actions that are intended to be useful in addressing immediate challenges and opportunities” (Fisher et al., 2020: 1002). In terms of operational activities, hustling often involved rapidly discarding the “baggage” of prior ways of doing things to allow experimentation with new activities. For example, Jen Hyman (co-founder, Rent the Runway—a company that provides designer clothing rentals) described her resilient organization as taking a “kind of scrappy and nimble” approach. In some cases, hustling involved repurposing capabilities. For instance, Brian Chesky (co-founder, Airbnb) explained, “We have a recruiting team. Maybe we could dedicate a percentage of the recruiting team to do job outplacement for the people being laid off. Maybe they could basically be an outplacement team to help them find jobs.” To repurpose, Jeremy Zimmer (co-founder, United Talent—an agency representing entertainment professionals) went back to opportunities rejected in the past for a second look, especially given the current lack of potential opportunities. Hustling involved engaging in real-time operational adjustments to “play the hand they were dealt” (Sarah Harden, CEO, Hello Sunshine) and being “open minded” to “obtain some small wins despite the really big hits” (Christina Tosi, founder, Milk Bar). The purpose of hustling was to provide sufficient operating revenue that would allow the organizations to be resilient to the adversity, regain a fit with their changing external environments by redefining themselves, and prepare for an economy that should improve (when the adverse event eventually fades). Hustling was a way of quickly “trying on” different approaches that might serve as both short- and long-term solutions for these organizations that faced a large initial drop in the market demand for their primary products and services. For example, Jeremy Zimmer (co-founder, United Talent) indicated that “we are all trying to manage our resources as carefully as we can so that when things start to come back to normal, we will be healthy and able to take advantage of the return to normal.” With a little more vision for the future, Sarah Harden (CEO, Hello Sunshine) believed that her company had “planted some wonderful seeds of development that will hopefully grow in the years to come.” Realigning resilient organizations The realigning organizations broadly altered their operations by reimagining and renewing their current routines to overcome new constraints. Routines are “stable patterns of behavior that characterize organizational reactions to variegated, internal or external stimuli” (Zollo & Winter, 2002: 340). To reinvent current routines is to rethink them and use them differently or with different configurations. Consistent with the strategy of redeploying resources from less productive business areas to those that show more promise (consistent with real options reasoning (McGrath, 1999)), the realigning resilient organizations sought to maximize their repurposing efforts to increase resource productivity. For example, Whitney Wolfe (founder, Bumble—an online dating platform on which women make the first contact) explained how the adverse environment (and the dip in market demand) encouraged her to think differently about her organization’s operations:This is an opportunity to hire in a way that we never thought about before. … we’re opening up our talent pool opportunity. . . . And of course, this has posed new demands. We need to lean into social growth more. And so you hire for that, or we need to double down here. Operations need to be adapted to the shift in strategic emphasis. Loren and Lisa Poncia (co-founders, Stemple Creek Ranch—organic products and event venue) explained the operational changes required to satisfy their organization’s online customers:[Enacting our strategy] became the logistical issue of how do we take all of this product that was processed and . . . cut and wrapped and ready to sell, like, in large quantities and pieces to restaurants and food service and somehow process that into retail cuts so that we could have them available for the direct-to-consumer sales. Beyond meeting the new environment’s emerging operational needs, the realigning organizations also sought to address challenging operational constraints by adjusting and/or redeploying resources. Interestingly, our data showed that these organizations’ exploration of new ways to address operational challenges caused by the adversity-induced dip in market demand may have generated new opportunities. For example, Alberto Perlman (co-founder, Zumba) explained how his organization tried to help its instructors address new operating conditions (i.e., no access to gyms, which were the primary medium for delivering the product) and realize new opportunities. He said,One of the ways we’ve helped is we really push our instructors and motivate our instructors to teach outdoors and tell our gym partners. Our instructors can teach in parking lots, in the parking lot at your gym, and you can partner with them and host these classes there. … And so I can generate revenue twice. I can generate revenue for my people who are live, in-person with me, and I can do it at the same time with people all over the world. (Emphasis added) Capitalizing resilient organizations The capitalizing resilient organizations faced a somewhat contradictory challenge. While they were strategically well-positioned to capture value during the pandemic (via a positive jump in market demand), the possibility of rapid growth resulted in significant operational issues. For this reason, these organizations altered their operations by rapidly scaling them to capture value from the surge in demand. Therefore, the increased demand for their products and services (or a subset of them) and their incremental adjustments to grasp proximal opportunities provided the capitalizing resilient organizations with significant growth potential. However, with growth, they experienced challenges in expanding operations (far) beyond what they were initially designed to handle. Therefore, to continue to grow (in the face of the current adversity), they needed to resolve often ambiguous and complex operational limitations related to scaling. Scaling refers to “spreading excellence within an organization as it grows” (Shepherd & Patzelt, 2022: 1). For example, Jessie Woolley-Wilson (CEO, DreamBox—online software for mathematics education) explained the scaling challenges her company faced in this way: Most people say, “Oh, it’s so great—an exponential growth.” And what I say in response to that is when you grow really fast, you get stretch marks. And we got stretch marks—our stretch marks where our support system was overwhelmed. And this was at a time when . . . usually it was a low period, typically. So gearing up for the fall, busy back to school season. And so we looked at our team and we said, “You’re going to have to sprint out.” And it was very, very difficult because it meant that we had to stretch ourselves. Similarly, other capitalizing resilient organizations faced operational challenges in delivering products/services, given the seemingly exponential increase in their market demand. For example, John Foley (co-founder, Peloton) explained, “There’s been a wind in our sail.... [but] there’s a waiting list for people to get their Peloton just because of the surge,” which was exacerbated by a substantial disruption to the production of key materials for Peloton’s products. Similarly, Sandra Oh Lin (co-founder, KiwiCo) noted there was a need to “make sure we had enough inventory available,” and Vlad Teneve (co-founder, Robinhood) reported that there was so much frenzied trading that the company could not handle it. Indeed, Mark Gainey and Michael Hovarth highlighted Strava’s operational challenges:It took a lot of work to even be able to handle the increased load. We went from adding about a million new athletes [customers] to the platform every month, two [million] at some point, three million a month, and it settles down to about two million a month now. So we, overnight, kind of had to go to a different mode of operating. Though it’s software, you still have a lot of hardware somewhere that’s running all of this, and scaling all that up and making sure that it wouldn’t all fall down and crumble . . . under the increased load. . . . But let’s do it in the way we believe is scalable long term. And so, in the midst of the pandemic, we shifted the paywall. (Emphasis added) The organizations’ reliance on their communication and coordination capabilities was critical to scaling operations to continue organizational growth. For example, Stewart Butterfield (co-founder, Slack—a platform for chat rooms and messaging) emphasized the importance of communication for effective operations:Also, we just invested so much over the last five years in a disciplined culture around communication, partly because of the use of our own product and partly just because we realized how important it was. This transition, I think, was relatively easy because we had already invested so much in a style of working in ways of reporting progress and keeping people updated and coordinated. Discussion Review of key findings In our findings above, we detailed different pathways in responding to an adverse event that each led to a form of organizational resilience. Specifically, we focused on variance in firm responses when the adverse event was held constant (i.e., all firms responded to the same event) in hopes of isolating and learning about different pathways to resilience. We detailed how the resilient organizations experienced, interpreted, and responded to the adverse event differently. Our findings revealed how the capitalizing resilient organizations, realigning resilient organizations, and repurposing resilient organizations differed across (1) the impact of the adverse event on the demand of their primary markets and responses through their (2) interpretation of the adversity and decision making, (3) strategic change initiatives, and (4) operational activities. Therefore, we explain the organizations’ different paths to organizational resilience and how their decision making and strategic and operational responses differed. Figure 2 summarizes our findings in a model of organizational resilience responses to an adverse event. Before discussing the implications of our study, we elaborate on the model as a theory on resilience responses.Fig. 2 Model of organizational resilience responses to an adverse event First, differences in organizational situations at the onset of the pandemic shaped resilience trajectories. Organizations will differ in their positioning related to environmental happenings in any situation. At the onset of the pandemic, rapid product/service demand surges or declines impacted organizations differently. This was due to luck rather than advanced planning in many ways—the pandemic was certainly not a scenario many organizations and governments planned for. This finding differs from the bulk of prior scholarship that focuses on preparing an organizational resilience response by engaging in activities for adjusting and responding (Ahmed et al., 2021; Williams et al., 2017). In contrast, the organizations in our data interpreted their specific situation differently, spurring different trajectories for how they achieved resilience. For example, capitalizing resilience organizations noted a sudden and high demand for certain products and services, which had to be managed using diminished supply lines and flexibility. By implementing simple rules decision-making, capitalizing organizations could cope with the surge in demand and harvest the benefits that faced them. This finding introduces a new perspective on resilience and adversity—adversity can come from organizations experiencing ‘too much of a good thing’ (i.e., a massive surge in demand). Simple rules can help them navigate that surge. In contrast, realigning resilience organizations faced a different challenge from the common source of adversity—the marginal reduction in the need for pre-adversity products/services that were now more difficult to take to market. Like capitalizing organizations, realigning organizations needed to develop and deliver products despite environmental constraints. They did so by employing values-based decision-making to help guide their thinking and manage competing tensions—demand for products and limitations of the workforce. Again, this finding differs from extant research, emphasizing increased demand coupled with decreased ability to deliver. While the scale of demand was not as significant as capitalizing organizations, it still presented an imminent economic and moral challenge. Repurposing organizations faced perhaps the most ‘traditional’ situation typically associated with resilience—they experienced a direct and imminent threat to operations due to a sudden and dramatic decrease in demand. Faced with this threat, we found that these organizations did something somewhat unusual—they identified and communicated a ‘worst case’ scenario to the workforce to guide decision-making. In doing so, they laid the groundwork for mobilizing their employees to enact drastic organizational changes in the form of wholesale pivots. This approach differs from extant research emphasizing maintenance of functioning among resilient organizations, which often assumes that maintenance involves persisting in the same activities. In contrast, we found that repurposing organizations emphatically and dramatically identified challenges to their business, galvanizing employees around a common decision-making framework for what to do next. Second, we found differences in the strategic change initiatives and operational activities across the three pathways demonstrating critical differences in operationalizing resilience. Much prior research on resilience describes what resilience is (maintenance of functioning) without fully capturing how functioning is achieved and then maintained (Ahmed et al., 2021; Williams et al., 2017). Our findings and theorizing begin to address this by showing at least three ways organizations maintained an (in some cases, enhanced) functioning. Capitalizing organizations made rapid, incremental adjustments to adapt to the sudden surge in demand. After these initial adjustments, they could systematize the revised system by scaling operations. This combination of rapid incremental then wholesale changes allowed them to avoid changing processes too quickly, test iterations of adjustments, and then scale the most appropriate models. In contrast, realigning resilience organizations gradually shifted their focus—making less dramatic changes. This gradual approach allowed them to re-think and re-invent processes to continue fulfilling ongoing demand. Indeed, had these organizations taken the approach of capitalizing organizations, the adjustments likely would have been too severe, “over-correcting” instead of taking more appropriate adjustments. Repurposing organizations took different approaches to enact strategic changes and align their operations with them. These organizations made dramatic pivots in their product portfolio and business practices to fight for survival. This involved imagining alternative strategic scenarios and then hustling to address resource gaps and find opportunities to make those alternatives a reality. These hustling practices demonstrated resourcefulness and creativity (Williams et al., 2021) in overcoming barriers that were suddenly present. Our findings in this area provide new insights into how organizational resilience is achieved. Indeed, while resilience is sometimes framed as a capability or stock that pre-dates a “crisis,” we found that resilience involves resourceful practices and actions to rapidly realign and redeploy existing resource stocks to new ends. Finally, the three paths we theorize different conceptualizations of resilience in kind and the general approaches to achieving resilience. These differences in kind are significant theoretically and have many implications for how resilience is achieved, developed, and/or cultivated. Specifically, we found that some organizations increased positive functioning (capitalizing), while others adjusted (realigning) for or found (repurposing) positive functioning. These different verbs demonstrate important insights into how organizations can prepare for and enact resilience when facing various challenging scenarios. Furthermore, our model naturally captures a moment in time in what is (as of this writing) an ongoing adverse event. This contextual feature is crucial as it demonstrates how organizations are resilient for now and provides insight into the long-term viability of these responses, given different trajectories. For example, while we did not observe cross-trajectory movement in our data, we could theorize that a capitalizing organization will likely eventually experience a drop in demand. This drop could result in them behaving in ways similar to the realigning or repurposing trajectory. It could be that having grown so rapidly, the organization cannot be resilient to the dramatic drop in demand. Similarly, repurposing organizations may succeed and then experience rapid growth—requiring another pivot to adjust to the demand for scale. In brief, while our data do not speak directly to these situations, our theorizing provides a framework for examining these questions. Theoretical contributions Organizational resilience Our findings and model of organizational resilience responses provide new insights into the entrepreneurship literature. First, previous organizational research on adverse events focuses on disruptive effects arising from diverse types of adverse events and, in turn, how an entrepreneurial response can ensure survival and accelerate recovery or face considerable and sustained disruption to operations and performance (Ahmed et al., 2021; Benner & Zenger, 2016; Meyer, 1982; Stieglitz et al., 2016; Wenzel et al., 2020). This study provides insights into entrepreneurship literature beyond the broad categorization of organizations as “resilient or not.” Specifically, we found variation in the phenomena of organizational resilience to the same adverse event, paving the way for an understanding of different resilience paths for established organizations. Indeed, our findings shed new light on three categories of resilient organizations—repurposing, realigning, and capitalizing—and their different response paths. Therefore, we move beyond the “all or none” and “one size fits all” approaches to explain multiple resilience paths. Furthermore, we highlight how differences in the impact of the adverse event on the demand of the focal organization’s primary markets influence how organizations respond—and thus the form and process of their resilience. Second, previous research on post-adversity growth has increased our understanding of adversity outcomes (at the individual level (Maitlis, 2009, 2012, 2020) and new ventures’ trial by fire (Bradley et al., 2011; Swaminathan, 1996)). Considering the potential upside to adverse events for individuals and organizations is essential. Indeed, while an adverse event can disrupt societal building blocks (Williams & Shepherd, 2021), this disruption also provides a context for trying new things that might have previously been impossible. The current study contributes new insights to the recovery stream of research on individuals’ post-adversity growth by highlighting how not all organizations that face an adverse event experience disruption (i.e., they do not need to recover from a substantial disruption), yet they can still benefit from post-adversity growth. That is, distinct from the growth generated by recovering from an adverse event, the actors we studied did not first need to suffer dysfunction to grow; they were resilient to the adversity, including growing their organizations under the new environmental conditions. Although sample organizations were in the right place at the right time (perhaps through luck (Liu & De Rond, 2016)), they still recognized the event as adverse. They responded to numerous challenges to achieve different forms of organizational resilience. Therefore, we provided new insights into post-adversity growth by pushing its boundary conditions beyond individuals recovering from adversity to organizations resilient to adversity. Specifically, we offer new insights by highlighting how some organizations are resilient to an adverse event (do not experience dysfunction) but can still grow due to the experience. The adversity is sufficient to capture the entrepreneur’s attention and motivate change to capitalize on growth opportunities without a substantial and sustained drop in the organization’s functioning. Finally, previous research has revealed the importance of resource endowments for determining whether an organization is resilient or not to an adverse event (Carmeli & Markman, 2011; Lengnick-Hall et al., 2011; Stephens et al., 2013). We contribute to this stream of research by indicating why, over and above resources, organizations differ in their form of organizational resilience based on how they experience the same adverse event and respond to it. We are not saying that resources are not necessary. They are. However, an adverse event can strike groups of organizations in different ways (despite resource endowments). Moreover, how organizations interpret, make decisions, undertake strategic action, and perform operational activities impacts their post-adversity outcomes over and above their pre-adversity resource endowments. Therefore, we provide new insights into the importance of how resilient organizations frame their circumstances, make decisions, and then deploy their resources under adversity over and above the initial stock of those resources when adversity strikes (i.e., the organization’s resource endowment). Entrepreneurial pivots Our findings also have implications for the growing literature on pivots (Grimes, 2018; Hampel et al., 2020; Manolova et al., 2020; Morgan et al., 2020) and business model change and innovation (Bock et al., 2021; Chesbrough, 2010; Martins et al., 2015; Saebi et al., 2017; Zott & Amit, 2010). Pivots occur when entrepreneurs decide to redefine their businesses radically. Such a radical change in the business model can risk disrupting relationships with stakeholders (e.g., Hampel et al., 2020). However, the risk from pivoting seems less salient in an adverse event where relationships with stakeholders are already substantially disrupted—the business would be pivoting in disrupted relationships rather than causing the disruption in stakeholder relationships. A pivot can increase a business model’s coherence—“the extent to which the entrepreneurial manager’s (or entrepreneurial managers’ shared) cognitive structures, that organize managerial understanding, parsimoniously represent the value creation and value capture factors and mechanisms that account for evidence of an opportunity (such as evidence of markets, technologies, stakeholders’ beliefs, and so on)” (Shepherd, Seyb & George, 2022). Business-model changes to achieve coherence, especially environmental changes, are critical to firm survival and performance (Bock et al., 2021; Chesbrough, 2010; Martins et al., 2015; Saebi et al., 2017; Zott & Amit, 2010). Therefore, the current study provides new insights into the business model change and pivoting literature. First, an adverse event can lead to a substantial change in demand that requires a pivot to a new business model to survive. This study indicates how those organizations that face a substantial drop in demand change their business model through their decision-making, strategic initiatives, and operational activities. Therefore, we provide new insights into some of the micro-activities of business model change (i.e., founders’ business-model-change behaviors) beyond work on the role of founders’ cognition in business-model change (Baden-Fuller & Morgan, 2010; Doz & Kosonen, 2010; Martins et al., 2015; Shepherd et al., 2022; Snihur & Zott, 2020). Second, even organizations that faced the adverse event with a slight drop in demand (or even an increase) engaged in some form of business model innovation. Therefore, the three resilience pathways provide new insights into the different combinations of decision making, strategic initiatives, and operational tactics that founders use to change their business model depending on their perception of an adverse event. Finally, in exploring business model innovation, especially for those responding to an adverse event, it is important to relax a core assumption of the resource-based view—unlimited cognitive abilities (Massa et al., 2017), to highlight how the founder’s interpretation of the event and the subsequent decision making drive business model innovation through strategic initiative activities and operational changes (regardless of the organization’s resource endowment or status or leadership in its industry). We provide new insights into how resources are used for business model change and reflect resilience to an adverse event providing more detail to the emerging research stream of the micro-dynamics of strategic management (e.g., Bendig et al., 2018; Helfat & Peteraf, 2009) and business model innovation (for a review see Massa et al., 2017). Limitations and future research Although this study has several strengths, it has some weaknesses, like all papers. Given the relatively short time frame and sample selection, we did not capture organizations in a fourth path that we know exists—failure or exit. The interviews were conducted for a podcast independent of the research team. While this provided some advantages, it also introduced some possible limitations. Perhaps the founders were motivated to offer socially desirable answers, given the public nature of the broadcast. However, given the responses, details of the founders’ hardships, and differences across the resilient organizations on different paths, social desirability is unlikely a concern. Of course, we were unable to ask follow-up questions. Still, the professional interviewer had a similar purpose for the broadcast (as we did for our research) and asked essential follow-up questions. We recognize that there are always questions about the generalizability or transferability of findings from inductive studies. The outcome of our theorizing is a proposed model that we hope future empirical research tests (in part or whole). It is an understatement that the COVID-19 pandemic is an extreme event. We expect that much of the model will apply to other substantial adverse events, but such an expectation will need to be tested by future empirical research. For example, the COVID-19 pandemic, as implied by definition, has impacted people worldwide, whereas most other adverse events impact specific regions; in addressing the spread of COVID-19, many economies have been locked down for extended periods exacerbating the adversity of the virus over an extended period whereas most events have a more temporary impact on businesses and people. Of course, the point of the inductive study is not to provide empirically generalizable findings but to use extreme events to push our thinking to generate new theories or elaborate on previous theories by pushing and stretching previous boundary conditions. The current model provides a theoretical basis for future theorizing and empirical research on different resilience paths to an adverse event. Indeed, we hope future research extends this line of research. There is an opportunity for scholars to offer a finer-grained treatment of organizational resilience than this study. For example, there may be categories of organizational resilience not represented or captured in the current study. Similarly, it could be fruitful to explore questions within each path of resilience—are there other differences within each path that future research could tease apart? Indeed, future research can focus on one of the aspects of a response path for a richer and more nuanced understanding of that aspect of organizational resilience than offered in the current model. For example, future research could build on this study’s findings to explore more details about decision-making processes (across organizations with different forms of resilience), including who is involved in decision making, where their attention (and their organizations’ attention) is focused, how the decision makers analyze and use the information and the speed with which decisions are made and enacted. Our findings on resilient organizations and their response paths provide opportunities for future research. Although these capitalizing resilient organizations needed to respond to numerous challenges, they all faced a positive jump in market demand for their primary products. We hope that future empirical research increases our understanding of these resilient organizations by investigating their counterfactuals—those organizations that experienced a positive jump in market demand but were unable to overcome the associated challenges and experienced diminished functioning (consistent with the notion of growth-induced organizational failure (e.g., Carroll, 1984)). Why are some organizations resilient to an adverse event that increases demand for their products/services while others are not? How do their response paths differ? Such research may indicate that an adverse event–induced jump in market demand may not be an unambiguous blessing for all organizations and how some can make the most of the new situation. Finally, we hope that future research considers the amount, type, and deployment of resources in the activities associated with the different organizational resilience paths. For example, how are resources acquired, combined, and deployed by resilient organizations (repurposing, realigning, and capitalizing) in their decision making, strategic change initiatives, and operational activities? There is much to learn about the nuances within and across the organizational resilience paths. Conclusion Adverse events can be highly disruptive to organizations. However, some organizations maintain positive functioning after a temporary period of unsettlement; these organizations are resilient to the adverse event. This study explored how organizations achieved resilience and fell into different categories of organizational resilience—repurposing, realigning, and capitalizing—each with a different response path. This study sheds new light on how resilient organizations vary in their adversity experiences; how some resilient organizations do better than simply maintain positive functioning in the face of an adverse event (i.e., increase functioning); and how resilient response paths are characterized by experiences with market demand changes, decision-making processes, strategic change initiatives, and operational activities. We hope this study’s findings provide a basis for future research on the variance and nuance in organizational resilience. 1 We acknowledge that some scholarship refers to “bouncing back” as resilience itself. However, we align our definition with the psychology literature that describes bouncing back as a recovery process. That is, individuals lose functioning and then bounce back (i.e., recover) (see Bonanno, 2012; Bonanno & Diminich, 2013; Bonanno, Romero, & Klein, 2015; Bonanno, Westphal, & Mancini, 2011 for reviews). Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Ahmed A Cacciotti G Ucbasaran D Williams TA Integrating psychological resilience, stress and coping in entrepreneurship: A systematic review and research agenda Entrepreneurship Theory & Practice 2021 10.1177/10422587211046542 Alexander DE Resilience and disaster risk reduction: An etymological journey Natural Hazards and Earth System Sciences 2013 13 11 2707 2716 10.5194/nhess-13-2707-2013 Alexander BN Greenbaum BE Shani AB Mitki Y Horesh A Organizational posttraumatic growth: Thriving after adversity Journal of Applied Behavioral Science 2021 57 1 30 56 10.1177/0021886320931119 Argyres N Bigelow L Nickerson JA Dominant designs, innovation shocks, and the follower's dilemma Strategic Management Journal 2015 36 2 216 234 10.1002/smj.2207 Baden-Fuller C Morgan MS Business models as models Long Range Planning 2010 43 2–3 156 171 10.1016/j.lrp.2010.02.005 Baker T Nelson RE Creating something from nothing: Resource construction through entrepreneurial bricolage Administrative Science Quarterly 2005 50 3 329 366 10.2189/asqu.2005.50.3.329 Ballesteros L Useem M Wry T Masters of disasters? An empirical analysis of how societies benefit from corporate disaster aid Academy of Management Journal 2017 60 5 1682 1708 10.5465/amj.2015.0765 Bartunek JM Louis MR Insider/outsider team research 1996 SAGE Publications Battilana J Lee M Advancing research on hybrid organizing–Insights from the study of social enterprises Academy of Management Annals 2014 8 1 397 441 10.5465/19416520.2014.893615 Battisti M Beynon M Pickernell D Deakins D Surviving or thriving: The role of learning for the resilient performance of small firms Journal of Business Research 2019 100 38 50 10.1016/j.jbusres.2019.03.006 Bechky BA Okhuysen GA Expecting the unexpected? How SWAT officers and film crews handle surprises Academy of Management Journal 2011 54 2 239 261 10.5465/amj.2011.60263060 Bendig D Strese S Flatten TC da Costa MES Brettel M On micro-foundations of dynamic capabilities: A multi-level perspective based on CEO personality and knowledge-based capital Long Range Planning 2018 51 6 797 814 10.1016/j.lrp.2017.08.002 Benner MJ Zenger T The lemons problem in markets for strategy Strategy Science 2016 1 2 71 89 10.1287/stsc.2015.0010 Bennis WG Thomas RJ Geeks and geezers: How era, values, and defining moments shape leaders-how tough times shape good leaders 2002 Harvard Business School Beunza D Stark D The organization of responsiveness: Innovation and recovery in the trading rooms of Lower Manhattan Socio-Economic Review 2003 1 2 135 164 10.1093/soceco/1.2.135 Bock AJ Warglien M George G A simulation-based approach to business model design and organizational change Innovation 2021 23 1 17 43 10.1080/14479338.2020.1769482 Boin A Disaster research and future crises: Broadening the research agenda International Journal of Mass Emergencies and Disasters 2005 23 3 199 214 10.1177/028072700502300310 Boin, A., Comfort, L. K., & Demchak, C. C. (2010). The rise of resilience. Designing resilience: Preparing for extreme events, 1. Bonanno GA Loss, trauma, and human resilience: Have we underestimated the human capacity to thrive after extremely aversive events? The American Psychologist 2004 59 1 20 28 10.1037/0003-066X.59.1.20 14736317 Bonanno GA Westphal M Mancini AD Resilience to loss and potential trauma Annual Review of Clinical Psychology 2011 7 511 535 10.1146/annurev-clinpsy-032210-104526 Bradley SW Aldrich H Shepherd DA Wiklund J Resources, environmental change, and survival: Asymmetric paths of young independent and subsidiary organizations Strategic Management Journal 2011 32 5 486 509 10.1002/smj.887 Bruyaka O Philippe D Castañer X Run away or stick together? The impact of organization-specific adverse events on alliance partner defection Academy of Management Review 2018 43 3 445 469 10.5465/amr.2014.0323 Bundy J Pfarrer MD A burden of responsibility: The role of social approval at the onset of a crisis Academy of Management Review 2015 40 3 345 369 10.5465/amr.2013.0027 Bundy J Pfarrer MD Short CE Coombs WT Crises and crisis management: Integration, interpretation, and research development Journal of Management 2017 43 6 1661 1692 10.1177/0149206316680030 Burgelman RA A process model of strategic business exit: Implications for an evolutionary perspective on strategy Strategic Management Journal 1996 17 S1 193 214 10.1002/smj.4250171012 Byrne, A., Crossan, M., & Seijts, G. (2018). The development of leader character through crucible moments. Journal of Management Education, 42(2), 265–293. 10.1177/1052562917717292 Calhoun, L. G., & Tedeschi, R. G. (2014). Handbook of posttraumatic growth: Research and practice. Routledge. Carmeli A Markman GD Capture, governance, and resilience: Strategy implications from the history of Rome Strategic Management Journal 2011 32 3 322 341 10.1002/smj.880 Carroll GR Dynamics of publisher succession in newspaper organizations Administrative Science Quarterly 1984 29 93 113 10.2307/2393082 Carroll, G. R., Delacroix, J. (1982) .Organizational mortality in the newspaper industries of Argentina and Ireland: An ecological approach Administrative Science Quarterly 169–198. 10.2307/2392299 Casselman, B., Cohen, P., Cowley, S., Dougherty, C., Kulish, N., McCabe, D. and Weise, K. (2020). Coronavirus cost to businesses and workers: ‘It has all gone to hell’. New York Times, March 15, 2020. https://www.nytimes.com/2020/03/15/business/economy/coronavirus-economy-impact.html Accessed May 3, 2021. Caza BB Barton MA Christianson MK Sutcliffe KM Conceptualizing the who, what, when, where, why and how of resilience in organizations 2020 Edward Elgar Publishing Center for Disease Control and Prevention. (2022). https://www.cdc.gov/. Accessed Feb 2022. Charmaz, K. (2014). Constructing grounded theory. Sage Publications. Chatterjee I Shepherd DA Wincent J Women’s entrepreneurship and well-being at the base of the pyramid Journal of Business Venturing 2022 37 4 106222 10.1016/j.jbusvent.2022.106222 Chesbrough H Business model innovation: Opportunities and barriers Long Range Planning 2010 43 2–3 354 363 10.1016/j.lrp.2009.07.010 Christensen CM Bower JJ Customer power, strategic investment, and the failure of leading firms Strategic Management Journal 1996 17 197 218 10.1002/(SICI)1097-0266(199603)17:3<197::AID-SMJ804>3.0.CO;2-U Christianson MK Farkas MT Sutcliffe KM Weick KE Learning through rare events: Significant interruptions at the Baltimore & Ohio Railroad Museum Organization Science 2009 20 5 846 860 10.1287/orsc.1080.0389 Comfort LK Birkland TA Cigler BA Nance E Retrospectives and prospectives on Hurricane Katrina: Five years and counting Public Administration Review 2010 70 5 669 678 10.1111/j.1540-6210.2010.02194.x Craven, M., Liu, L., Mysore, M., & Wilson, M. (2020). COVID-19: Implications for business. McKinsey & Company, 1–8. Crayne MP The traumatic impact of job loss and job search in the aftermath of COVID-19 Psychological Trauma: Theory, Research, Practice, and Policy 2020 12 S1 S180 10.1037/tra0000852 32478539 Crosina E Pratt MG Toward a model of organizational mourning: The case of former Lehman Brothers bankers Academy of Management Journal 2019 62 1 66 98 10.5465/amj.2017.0140 D’Adderio L The replication dilemma unravelled: How organizations enact multiple goals in routine transfer Organization Science 2014 25 5 1325 1350 10.1287/orsc.2014.0913 Darkow PM Beyond “bouncing back”: Towards an integral, capability-based understanding of organizational resilience Journal of Contingencies and Crisis Management 2019 27 2 145 156 10.1287/orsc.2014.0913 David, M., & Sutton, C. D. (2004). Social research: The basics (Vol. 74, No. 3). Thousand Oaks: Sage. Davis JP Eisenhardt KM Bingham CB Optimal structure, market dynamism, and the strategy of simple rules Administrative Science Quarterly 2009 54 3 413 452 10.2189/asqu.2009.54.3.413 Dewald J Bowen F Storm clouds and silver linings: Responding to disruptive innovations through cognitive resilience Entrepreneurship Theory and Practice 2010 34 1 197 218 10.1111/j.1540-6520.2009.00312.x Drabek TE Managing the emergency response Public Administration Review 1985 45 85 92 10.2307/3135002 Doz YL Kosonen M Embedding strategic agility: A leadership agenda for accelerating business model renewal Long Range Planning 2010 43 2–3 370 382 10.1016/j.lrp.2009.07.006 Dutton JE Jackson SE Categorizing strategic issues: Links to organizational action Academy of Management Review 1987 12 1 76 90 10.5465/amr.1987.4306483 Dynes RR Noah and disaster planning: The cultural significance of the flood story Journal of Contingencies and Crisis Management 2003 11 4 170 177 10.1111/j.0966-0879.2003.01104003.x Eggers JP Park KF Incumbent adaptation to technological change: The past, present, and future of research on heterogeneous incumbent response Academy of Management Annals 2018 12 1 357 389 10.5465/annals.2016.0051 Eisenhardt KM Building theories from case study research Academy of Management Review 1989 14 4 532 550 10.5465/amr.1989.4308385 Eisenhardt KM Graebner ME Theory building from cases: Opportunities and challenges Academy of Management Journal 2007 50 1 25 32 10.5465/amj.2007.24160888 Eisenhardt KM Sull DN Strategy as simple rules Harvard Business Review 2001 79 1 106 116 Fairlie, R. W. (2020). The impact of COVID-19 on small business owners: Continued losses and the partial rebound in May 2020. NBER working paper, w27462. Finkelstein S Interindustry merger patterns and resource dependence: A replication and extension of Pfeffer (1972) Strategic Management Journal 1997 18 787 810 10.1002/(SICI)1097-0266(199711)18:10<787::AID-SMJ913>3.0.CO;2-R Fischbacher-Smith D Beyond the worst case scenario: ‘Managing’ the risks of extreme events Risk Management 2010 12 1 1 8 10.1057/rm.2009.17 Fisher G Stevenson R Neubert E Burnell D Kuratko DF Entrepreneurial hustle: Navigating uncertainty and enrolling venture stakeholders through urgent and unorthodox action Journal of Management Studies 2020 57 5 1002 1036 10.1111/joms.12584 Galatzer-Levy IR Huang SH Bonanno GA Trajectories of resilience and dysfunction following potential trauma: A review and statistical evaluation Clinical Psychology Review 2018 63 41 55 10.1016/j.cpr.2018.05.008 29902711 Gartenberg C Do parents matter? Effects of lender affiliation through the mortgage boom and bust Management Science 2014 60 11 2776 2793 10.1287/mnsc.2014.1944 Gephart RP Jr Van Maanen J Oberlechner T Organizations and risk in late modernity Organization Studies 2009 30 2–3 141 155 10.1177/0170840608101474 Giones F Brem A Pollack JM Michaelis TL Klyver K Brinckmann J Revising entrepreneurial action in response to exogenous shocks: Considering the COVID-19 pandemic Journal of Business Venturing Insights 2020 14 e00186 10.1016/j.jbvi.2020.e00186 Grattan LM Brumback B Roberts SM Buckingham-Howes S Toben AC Morris G “Bouncing back” after the Deepwater Horizon oil spill Disaster Prevention and Management: An International Journal 2017 26 122 133 10.1108/DPM-09-2016-0195 Grimes MG The pivot: How founders respond to feedback through idea and identity work Academy of Management Journal 2018 61 5 1692 1717 10.5465/amj.2015.0823 Grimes, M. G., Williams, T. A., & Zhao, E. Y. (2019). Anchors aweigh: The sources, variety, and challenges of mission drift. Academy of Management Review, 44(4), 819–845. 10.5465/amr.2017.0254 Grodal S Anteby M Holm AL Achieving rigor in qualitative analysis: The role of active categorization in theory building Academy of Management Review 2021 46 3 591 612 10.5465/amr.2018.0482 Gunderson LH Ecological resilience—in theory and application Annual Review of Ecology and Systematics 2000 31 1 425 439 10.1146/annurev.ecolsys.31.1.425 Hampel CE Tracey P Weber K The art of the pivot: How new ventures manage identification relationships with stakeholders as they change direction Academy of Management Journal 2020 63 2 440 471 10.5465/amj.2017.0460 Haroon O Rizvi SAR COVID-19: Media coverage and financial markets behavior—A sectoral inquiry Journal of Behavioral and Experimental Finance 2020 27 100343 10.1016/j.jbef.2020.100343 32427152 Helfat CE Know-how and asset complementarity and dynamic capability accumulation: The case of R&D Strategic Management Journal 1997 18 5 339 360 10.1002/(SICI)1097-0266(199705)18:5<339::AID-SMJ883>3.0.CO;2-7 Helfat CE Peteraf MA Understanding dynamic capabilities: Progress along a developmental path Strategic Organization 2009 7 1 91 102 10.1177/1476127008100133 Herbane B Rethinking organizational resilience and strategic renewal in SMEs Entrepreneurship & Regional Development 2019 31 5–6 476 495 10.1080/08985626.2018.1541594 Interos (2021). Ineros Annual Global Supply Chain Support. https://www.interos.ai/resources/global-supply-chain-report/ Jackson, S. E., Dutton, J. E. (1988). Discerning threats and opportunities Administrative Science Quarterly 370–387. 10.2307/2392714 Kahn WA Barton MA Fisher CM Heaphy ED Reid EM Rouse ED The geography of strain: Organizational resilience as a function of intergroup relations Academy of Management Review 2018 43 3 509 529 10.5465/amr.2016.0004 Klein, A. & Smith, E. (2021). Explaining the economic impact of COVID-19: Core industries and the Hispanic workforce. https://www.brookings.edu/research/explaining-the-economic-impact-of-covid-19-core-industries-and-the-hispanic-workforce/ Kreps, G. A., & Bosworth, S. L. (1993). Disaster, organizing, and role enactment: A structural approach. American Journal of Sociology, 99(2), 428–463. http://www.jstor.org/stable/2781684. Kuratko, D. F., Fisher, G., Audretsch, D. B. (2020) Unraveling the entrepreneurial mindset Small Business Economics 1–11. 10.1007/s11187-020-00372-6 Lagadec, P. (2007). Crisis management in the twenty-first century: “Unthinkable” events in “inconceivable” contexts. In Handbook of disaster research (pp. 489–507). Springer, New York, NY. Laufer D Coombs WT How should a company respond to a product harm crisis? The role of corporate reputation and consumer-based cues Business Horizons 2006 49 5 379 385 10.1016/j.bushor.2006.01.002 Locke K Grounded Theory in Management Research 2001 Sage Lalonde C Roux-Dufort C Crisis management in institutional healthcare settings: From punitive to emancipatory solutions Organization Development Journal 2010 28 1 19 Lengnick-Hall, C. A., & Beck, T. E. (2005). Adaptive fit versus robust transformation: How organizations respond to environmental change. Journal of Management, 31(5), 738–757. 10.1177/0149206305279367 Lengnick-Hall CA Beck TE Lengnick-Hall ML Developing a capacity for organizational resilience through strategic human resource management Human Resource Management Review 2011 21 3 243 255 10.1016/j.hrmr.2010.07.001 Linnenluecke, M. K., & Griffiths, A. (2015). The climate resilient organization: Adaptation and resilience to climate change and weather extremes. Edward Elgar Publishing. Liu C De Rond M Good night, and good luck: Perspectives on luck in management scholarship Academy of Management Annals 2016 10 1 409 451 10.5465/19416520.2016.1120971 Maitlis S Posttraumatic growth at work Annual Review of Organizational Psychology and Organizational Behavior 2020 7 395 419 10.1146/annurev-orgpsych-012119-044932 Maitlis, S. (2012). Posttraumatic growth: A missed opportunity for positive organizational scholarship. The Oxford handbook of positive organizational scholarship, 909–923. Maitlis, S. (2009). Who am I now? Sensemaking and identity in posttraumatic growth. Exploring positive identities and organizations: Building a theoretical and research foundation, 47–76. Manolova TS Brush CG Edelman LF Elam A Pivoting to stay the course: How women entrepreneurs take advantage of opportunities created by the COVID-19 pandemic International Small Business Journal 2020 38 6 481 491 10.1177/0266242620949136 35125599 Martins LL Rindova VP Greenbaum BE Unlocking the hidden value of concepts: A cognitive approach to business model innovation Strategic Entrepreneurship Journal 2015 9 1 99 117 10.1002/sej.1191 Martinez MG Zouaghi F Marco TG Robinson C What drives business failure? Exploring the role of internal and external knowledge capabilities during the global financial crisis Journal of Business Research 2019 98 441 449 10.1016/j.jbusres.2018.07.032 Massa L Tucci CL Afuah A A critical assessment of business model research Academy of Management Annals 2017 11 1 73 104 10.5465/annals.2014.0072 McGrath RG Falling forward: Real options reasoning and entrepreneurial failure Academy of Management Review 1999 24 1 13 30 10.5465/amr.1999.1580438 McKay, B. (2021). U.S. drug-overdoes deaths soared nearly 30% in 2020, driven by synthetic opioids. The Wall Street Journal. McMullen JS Shepherd DA Patzelt H Managerial (in) attention to competitive threats Journal of Management Studies 2009 46 2 157 181 10.1111/j.1467-6486.2008.00799.x Meyer, A. D. (1982). Adapting to environmental jolts. Administrative Science Quarterly, 27, 515–537. https://www.jstor.org/stable/2392528 Mittermaier, A., Patzelt, H., Shepherd, D. A. (2022a). Motivating Prosocial Venturing in Response to a Humanitarian Crisis: Building Theory From the Refugee Crisis in Germany Entrepreneurship Theory and Practice 10422587211025233. 10.1177/10422587211025233 Mittermaier, A., Shepherd, D. A., Patzelt, H. (2022b). We cannot direct the wind, but we can adjust the sails: Prosocial ventures’ responses to potential resource threats Organization Science 1–26. 10.1287/orsc.2021.1465 Morgan T Anokhin S Ofstein L Friske W SME response to major exogenous shocks: The bright and dark sides of business model pivoting International Small Business Journal 2020 38 5 369 379 10.1177/0266242620936590 Neal DM Phillips BD Effective emergency management: Reconsidering the bureaucratic approach Disasters 1995 19 4 327 337 10.1111/j.1467-7717.1995.tb00353.x 8564456 Ogle, C. M., Rubin, D. C., Berntsen, D., & Siegler, I. C. (2013). The frequency and impact of exposure to potentially traumatic events over the life course. Clinical Psychological Science, 1(4), 426–434. 10.1177/2167702613485076 Pacheco-de-Almeida G Erosion, time compression, and self-displacement of leaders in hypercompetitive environments Strategic Management Journal 2010 31 13 1498 1526 10.1002/smj.896 Park B Rogan M Capability reputation, character reputation, and exchange partners’ reactions to adverse events Academy of Management Journal 2019 62 2 553 578 10.5465/amj.2016.0445 Paukert, C. (2020). Hertz declares bankruptcy, blames COVID-19. Road Show https://www.cnet.com/roadshow/news/hertz-bankrupt-covid-19-coronavirus-chapter-11-rental-car/ Pearce JA Robbins DK Retrenchment remains the foundation of business turnaround Strategic Management Journal 1994 15 5 407 417 10.1002/smj.4250150507 Pearson CM Clair JA Reframing crisis management Academy of Management Review 1998 23 1 59 76 10.5465/amr.1998.192960 Perrow C The limits of safety: The enhancement of a theory of accidents Journal of Contingencies and Crisis Management 1994 2 4 212 220 10.1111/j.1468-5973.1994.tb00046.x Pfeffer, J., & Salancik, G. R. (2003). The external control of organizations: A resource dependence perspective. Stanford University Press. Powell EE Baker T It's what you make of it: Founder identity and enacting strategic responses to adversity Academy of Management Journal 2014 57 5 1406 1433 10.5465/amj.2012.0454 Powley EH Reclaiming resilience and safety: Resilience activation in the critical period of crisis Human Relations 2009 62 9 1289 1326 10.1177/0018726709334881 Pratt MG Rockmann KW Kaufmann JB Constructing professional identity: The role of work and identity learning cycles in the customization of identity among medical residents Academy of Management Journal 2006 49 2 235 262 10.5465/amj.2006.20786060 Quarantelli, E. L. (1998). What is a disaster?: Perspectives on the question. Psychology Press. Quarantelli EL Perry RW A social science research agenda for the disasters of the 21st century: Theoretical, methodological and empirical issues and their professional implementation What is a Disaster 2005 325 396 Rahmandad H Repenning N Capability erosion dynamics Strategic Management Journal 2016 37 4 649 672 10.1002/smj.2354 Ries, E. (2011). The lean startup: How today's entrepreneurs use continuous innovation to create radically successful businesses. Currency. Robbins DK Pearce JA Turnaround: Retrenchment and recovery Strategic Management Journal 1992 13 4 287 309 10.1002/smj.4250130404 Roberts LM Dutton JE Spreitzer GM Heaphy ED Quinn RE Composing the reflected best-self portrait: Building pathways for becoming extraordinary in work organizations Academy of Management Review 2005 30 4 712 736 10.5465/amr.2005.18378874 Rosenthal U September 11: Public administration and the study of crises and crisis management Administration & Society 2003 35 2 129 143 10.1177/0095399703035002001 Roux-Dufort C Is crisis management (only) a management of exceptions? Journal of Contingencies and Crisis Management 2007 15 2 105 114 10.1111/j.1468-5973.2007.00507.x Roux-Dufort C Delving into the roots of crises: The genealogy of surprise The Handbook of International Crisis Communication Research 2016 43 24 10.1002/9781118516812.ch3 Roux-Dufort C Lalonde C Exploring the theoretical foundations of crisis management Journal of Contingencies and Crisis Management 2013 21 1 1 3 10.1111/1468-5973.12014 Saebi T Lien L Foss NJ What drives business model adaptation? The impact of opportunities, threats and strategic orientation Long Range Planning 2017 50 5 567 581 10.1016/j.lrp.2016.06.006 Sayegh L Anthony WP Perrewé PL Managerial decision-making under crisis: The role of emotion in an intuitive decision process Human Resource Management Review 2004 14 2 179 199 10.1016/j.hrmr.2004.05.002 Seckler, C., Fischer, S., & Rosing, K. (2021). Who adopts an error management orientation? Discovering the role of humility. Academy of Management Discoveries. 10.5465/amd.2019.0172 Seville, E. (2016). Resilient organizations: How to survive, thrive and create opportunities through crisis and change. Kogan Page Publishers. Shepherd DA Williams TA Local venturing as compassion organizing in the aftermath of a natural disaster: The role of localness and community in reducing suffering Journal of Management Studies 2014 51 6 952 994 10.1111/joms.12084 Shepherd DA Williams T Entrepreneurship responding to adversity: Equilibrating adverse events and disequilibrating persistent adversity Organization Theory 2020 1 4 2631787720967678 10.1177/2631787720967678 Shepherd, D. A., & Patzelt, H. (2022). A call for research on the scaling of organizations and the scaling of social impact. Entrepreneurship Theory and Practice, 46(2), 255–268. 10.1177/104225872095059 Shepherd DA McMullen JS Ocasio W Is that an opportunity? An attention model of top managers' opportunity beliefs for strategic action Strategic Management Journal 2017 38 3 626 644 10.1002/smj.2499 Shepherd DA Saade FP Wincent J How to circumvent adversity? Refugee-entrepreneurs' resilience in the face of substantial and persistent adversity Journal of Business Venturing 2020 35 4 105940 10.1016/j.jbusvent.2019.06.001 Shepherd, D. A., Maitlis, S., Parida, V., Wincent, J., & Lawrence, T. B. (2021). Intersectionality in intractable dirty work: how Mumbai ragpickers make meaning of their work and lives. Academy of Management Journal, (ja). Shepherd, D. A., Seyb, S., & George, G. (2022). Grounding business models: cognition, boundary objects, and business-model change. Academy of Management Review, (ja). 10.5465/amr.2020.0173 Shrivastava, P. (1992). Bhopal: Anatomy of a crisis. Sage Publications Limited. Snihur Y Zott C The genesis and metamorphosis of novelty imprints: How business model innovation emerges in young ventures Academy of Management Journal 2020 63 2 554 583 10.5465/amj.2017.0706 Sommer A Pearson CM Antecedents of creative decision making in organizational crisis: A team-based simulation Technological Forecasting and Social Change 2007 74 8 1234 1251 10.1016/j.techfore.2006.10.006 Spreitzer, G. M., & Sutcliffe, K. M. (2007). Thriving in organizations. In D. L. Nelson & C. L. Cooper (Eds.), Positive organizational behavior (pp. 74–85). Thousand Oaks: Sage Publications. Stallings, R. A., & Quarantelli, E. L. (1985). Emergent citizen groups and emergency management. Public Administration Review, 45, 93–100. https://www.jstor.org/stable/3135003 Stam D van Knippenberg D Wisse B Nederveen Pieterse A Motivation in words: Promotion-and prevention-oriented leader communication in times of crisis Journal of Management 2018 44 7 2859 2887 10.1177/0149206316654543 Stephens JP Heaphy ED Carmeli A Spreitzer GM Dutton JE Relationship quality and virtuousness: Emotional carrying capacity as a source of individual and team resilience Journal of Applied Behavioral Science 2013 49 1 13 41 10.1177/0021886312471193 Stieglitz N Knudsen T Becker MC Adaptation and inertia in dynamic environments Strategic Management Journal 2016 37 9 1854 1864 10.1002/smj.2433 Strauss, A., & Corbin, J. M. (1997). Grounded theory in practice. Sage Publications. Strike VM Rerup C Mediated sensemaking Academy of Management Journal 2016 59 3 880 905 10.5465/amj.2012.0665 Sutcliffe KM Vogus TJ Cameron KS Dutton IE Quinn RE Organizing for resilience Positive organizational scholarship 2003 Berrett-Koehler 94 110 Swaminathan A Environmental conditions at founding and organizational mortality: A trial-by-fire model Academy of Management Journal 1996 39 5 1350 1377 10.5465/257002 Taleb, N. N. (2007). The black swan: The impact of the highly improbable. Random house. Tedeschi, R. G., & Calhoun, L. G. (1995). Trauma and transformation: Growing in the aftermath of suffering. SAGE Publications. Thomas JB Clark SM Gioia DA Strategic sensemaking and organizational performance: Linkages among scanning, interpretation, action, and outcomes Academy of Management Journal 1993 36 2 239 270 10.5465/256522 10125120 Topper B Lagadec P Fractal crises–a new path for crisis theory and management Journal of Contingencies and Crisis Management 2013 21 1 4 16 10.1111/1468-5973.12008 Tripsas M Technology, identity, and inertia through the lens of “The Digital Photography Company” Organization Science 2009 20 2 441 460 10.1287/orsc.1080.0419 Tripsas M Gavetti G Capabilities, cognition, and inertia: Evidence from digital imaging Strategic Management Journal 2000 21 10–11 1147 1161 10.1002/1097-0266(200010/11)21:10/113.0.CO;2-R Tsoukas H Chia R On organizational becoming: Rethinking organizational change Organization Science 2002 13 5 567 582 10.1287/orsc.13.5.567.7810 Turner, B. A. (1976). The organizational and interorganizational development of disasters Administrative Science Quarterly 378–397. 10.2307/2391850 Vera D Samba C Kong DT Maldonado T Resilience as thriving: The role of positive leadership practices Organizational Dynamics 2021 50 2 100784 10.1016/j.orgdyn.2020.100784 Wakabayashi, D. (2021). Google executives see cracks in their company’s success. New York Time. https://www.nytimes.com/2021/06/21/technology/sundar-pichai-google.html. Accessed Feb 2002. Weick KE The collapse of sensemaking in organizations: The Mann Gulch disaster Administrative Science Quarterly 1993 628–652 2393339 Weick, K. E., & Sutcliffe, K. M. (2011). Managing the unexpected: Resilient performance in an age of uncertainty Vol. 8. John Wiley & Sons. Wenger, D., Quarantelli, E. and Dynes, R. (1987). Disaster analysis: emergency management offices and arrangements. Final Report on Phase I, Disaster Research Center, University of Delaware, Newark, DE. Wenzel, M., Stanske, S., & Lieberman, M. B. (2020). Strategic responses to crisis. Strategic Management Journal, 41(7/18). 10.1002/smj.3161 Wiklund J Shepherd D Entrepreneurial orientation and small business performance: A configurational approach Journal of Business Venturing 2005 20 1 71 91 10.1016/j.jbusvent.2004.01.001 Wildavsky, A. B. (1988). Searching for safety (Vol. 10). Transaction publishers. Williams TA Gruber DA Sutcliffe KM Shepherd DA Zhao EY Organizational response to adversity: Fusing crisis management and resilience research streams Academy of Management Annals 2017 11 2 733 769 10.5465/annals.2015.0134 Williams TA Shepherd DA Building resilience or providing sustenance: Different paths of emergent ventures in the aftermath of the Haiti earthquake Academy of Management Journal 2016 59 6 2069 2102 10.5465/amj.2015.0682 Williams TA Shepherd DA Victim entrepreneurs doing well by doing good: Venture creation and well-being in the aftermath of a resource shock Journal of Business Venturing 2016 31 4 365 387 10.1016/j.jbusvent.2016.04.002 Williams TA Shepherd DA To the rescue!? Brokering a rapid, scaled and customized compassionate response to suffering after disaster Journal of Management Studies 2018 55 910 942 10.1111/joms.12291 Williams TA Shepherd DA Bounding and binding: Trajectories of community-organization emergence following a major disruption Organization Science 2021 10.1287/orsc.2020.1409 Williams, T. A., & Murphy, C. (2021). Ruminating on what you think of me: A grounded model of construed image work. Academy of Management Journal, (ja). 10.5465/amj.2020.0963 Williams TA Thorgren S Lindh I Rising from failure, staying down, or more of the same? An inductive study of entrepreneurial reentry Academy of Management Discoveries 2020 6 4 631 662 10.5465/amd.2018.0047 Williams T Zhao EY George G Sonenshein S Ucbasaran D Getting more for less: The role of resourcefulness in entrepreneurship Journal of Business Venturing 2021 10.5465/amd.2018.0047 Zhang Y Rajagopalan N Once an outsider, always an outsider? CEO origin, strategic change, and firm performance Strategic Management Journal 2010 31 3 334 346 10.1002/smj.812 Zimmerman FM Managing a successful turnaround Long Range Planning 1989 22 3 105 124 10.1016/0024-6301(89)90013-7 Zollo M Winter SG Deliberate learning and the evolution of dynamic capabilities Organization Science 2002 13 3 339 351 10.1287/orsc.13.3.339.2780 Zott C Amit R Business model design: An activity system perspective Long Range Planning 2010 43 2–3 216 226 10.1016/j.lrp.2009.07.004
PMC009xxxxxx/PMC9542470.txt	==== Front J Nucl Cardiol J Nucl Cardiol Journal of Nuclear Cardiology 1071-3581 1532-6551 Springer International Publishing Cham 36207574 3114 10.1007/s12350-022-03114-1 Cases with Images Cases from a busy nuclear cardiology laboratory Girard Andrew A. MD [email protected] 1 Elrod Jacob MD 2 Bhambhvani Pradeep MD 3 Hage Fadi G. MD 24 1 grid.265892.2 0000000106344187 Department of Medicine, The University of Alabama at Birmingham, 1720 2nd Ave S, BDB 327, Birmingham, AL 35233 USA 2 grid.265892.2 0000000106344187 Division of Cardiovascular Disease, Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL USA 3 grid.265892.2 0000000106344187 Division of Molecular Imaging and Therapeutics, Department of Radiology, The University of Alabama at Birmingham, Birmingham, AL USA 4 grid.280808.a 0000 0004 0419 1326 Section of Cardiology, Birmingham Veterans Affairs Medical Center, Birmingham, AL USA 7 10 2022 2023 30 3 11031109 9 9 2022 14 9 2022 © The Author(s) under exclusive licence to American Society of Nuclear Cardiology 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. issue-copyright-statement© American Society of Nuclear Cardiology 2023 ==== Body pmcCase 1 A 67-year-old woman with chronic low back pain and active tobacco use presents for a preoperative stress test for an abdominal aortic aneurysm repair. Her ability to exercise is limited by back pain. She denies any chest pain or shortness of breath at rest or with limited exertion. Physical examination is unremarkable with a blood pressure of 145/82 mm Hg, heart rate of 75 beats per minute (bpm), and oxygen saturation of 95% on room air. Regadenoson Single-Photon Emission Computed Tomography (SPECT) Myocardial Perfusion Imaging (MPI) using a GE Discovery 530 CZT camera demonstrated normal perfusion (Figure 1A). Review of the simulated rotating planar projection images was not revealing, but inspection of the individual planar projections demonstrated focal radiotracer uptake in the superior left thorax (Figure 1B).Figure 1 A Regadenoson SPECT MPI study demonstrating homogenous uptake of radiotracer throughout the left ventricular myocardium. B Right image: One of the 19 raw projection images revealed significant focal radiotracer uptake in the superior left thorax (red arrow). Left image: The simulated rotating planar projection image did not reproduce this finding. C FDG-PET scan revealed a hypermetabolic nodule (white arrow) in the superior left upper lobe of the lung which was determined to be poorly differentiated adenocarcinoma on biopsy A follow-up computed tomography (CT) scan of the chest with contrast revealed the presence of a 11 × 12 mm spiculated nodule in the left upper lobe of the lung. A fluorodeoxyglucose positron emission tomography (FDG-PET) scan confirmed avid FDG uptake (maximum standard uptake value [SUV] = 10) without evidence of nodal metastasis (Figure 1C). She underwent an endobronchial ultrasound with biopsy, confirming the diagnosis of poorly differentiated adenocarcinoma of the lung. She is currently awaiting a left upper lobectomy with thoracic surgery. Teaching points Nuclear stress imaging relies on the capture of gamma rays emitted from a decaying radiotracer. This is achieved using a detector (scintillator) mounted on a rotating or fixed gantry. In SPECT MPI, traditional Anger cameras rotate the detectors around the patient using a gantry to generate the image and therefore does not differentiate between cardiac and extra-cardiac structures. Dedicated cardiac cameras, such as the one used to image this patient, use advances in detector and collimator technologies to focus the image on the heart. This results in substantial improvement in sensitivity of detecting gamma rays emitted from the myocardium, and ultimately enhancement of spatial resolution in the cardiac region.1,2 However, this comes at the expense of reduced count sensitivity and resolution in the surrounding extra-cardiac regions. The estimated prevalence and distribution of incidental extra-cardiac findings (IECFs) seen during SPECT and PET MPI have been documented.3–5 It is essential that the interpreting physician examine all structures both within and outside of the myocardium during review of images since IECFs may be clinically important. For SPECT imaging, this entails visualizing the raw projection images. With the conventional Anger camera, inspection of the endless-loop cine of the raw data allows for visualizing IECFs adequately either as increased or decreased tracer uptake. With cardiac-focused cameras, the simulated rotating image may not show significant IECFs, as demonstrated in this case. The interpreting physician should routinely review the individual raw planar projections for IECFs on these cameras. Case 2 A 59-year-old woman with coronary artery disease, peripheral vascular disease, severe chronic obstructive pulmonary disease on home oxygen, and a 50 pack-year history of tobacco use presented to the clinic for episodes of substernal chest pain that have been increasing in frequency and severity over the last year. Physical examination was unremarkable with a heart rate of 92 bpm, blood pressure of 132/59 mm Hg, and an oxygen saturation of 98% on 2 L of oxygen by nasal cannula. She was referred for a pharmacologic nuclear stress test. Regadenoson SPECT MPI study with Technetium-99 m (Tc-99 m) showed normal perfusion. The simulated rotating planar projection images did not show any IECFs but a single raw planar projection showed focal radiotracer uptake located in the superior right thorax (Figure 2A). Review of rotating cine images obtained on an Anger camera 3 years prior did not show radiotracer uptake in the right lung at that time (Figure 2C). A CT scan confirmed the presence of a right apical lung nodule measuring approximately 7 × 10 mm with avid FDG uptake (maximum SUV = 4.2) on PET scan without evidence of nodal metastasis (Figure 2B).Figure 2 A Left panel: The simulated rotating projection image did not demonstrate an IECF. Right panel: A single raw projection planar image revealed focal radiotracer uptake (white arrow) in superior right thorax. B Cine rotating planar projection image on an Anger camera obtained 3 years prior did not show radiotracer uptake in that region. C FDG-PET scan showed a hypermetabolic nodule (SUV = 4.2) in the right lung apex without evidence of nodal metastasis Teaching points Solitary pulmonary nodule is a common IECF, typically discovered on a chest x-ray or CT scan. The risk of malignancy associated with a lung nodule (or nodules) is determined by assessing patient characteristics and nodule size, appearance, and count.6 Guidelines for the management of lung nodules are defined by the Fleischner Society.7 A solitary, spiculated pulmonary nodule measuring > 8 mm with the patient characteristics described in this case is considered high risk and requires either surveillance CT scans every 3 months, PET/CT imaging, or tissue sampling. In this case, the spiculated lung nodule had notable radiotracer uptake on both a SPECT MPI study and an FDG-PET scan. Similar to the prior case, the simulated rotating planar projection images did not reveal radiotracer uptake. Focal radiotracer uptake was only seen when the single planar projections were reviewed. Case 3 A 52-year-old man with end stage kidney disease (ESKD), due to focal segmental glomerulosclerosis, presents to clinic for a third kidney transplantation evaluation. He initially received a living donor kidney transplant in 1995. He developed severe allograft rejection the following year which required intermittent hemodialysis until he received a second transplant in 2000. Since that time, he had been on stable immunosuppressive therapy. However, over the last two years he experienced a progressive decline in renal function to stage four chronic kidney disease. Two months ago, he was hospitalized for COVID-19 infection and acute kidney injury. As a result, he has progressed to ESKD, and is currently undergoing peritoneal dialysis pending identification of a suitable kidney transplant donor. He was referred for nuclear stress testing as a part of his transplantation evaluation. Regadenoson SPECT MPI demonstrated normal perfusion. The simulated raw rotating planar projection images did not show any IECF (Figure 3A, right panel). However, focal radiotracer uptake was noted in the region of the thyroid and parathyroid glands on the planar projection images (Figure 3A, left panel). Thyroid function tests were normal. Parathyroid hormone (PTH) level was found to be elevated at 167.3 pg/mL with a calcium level of 9.3 mg/dL and a phosphorous level of 7.0 mg/dL. A Sestamibi parathyroid scan identified multigland parathyroid hyperplasia (Figure 3B).Figure 3 A Right panel: The simulated rotating planar projection images showed no IECF. Left panel: A raw projection planar image revealed significant radiotracer uptake in the regions of the thyroid and parathyroid glands (white arrow). The exact location of radiotracer uptake is difficult to discern, necessitating biochemical evaluation of thyroid and parathyroid function. B. Early, 2 h delayed, and 2 h delayed pinhole magnified Sestamibi parathyroid images show multigland parathyroid hyperplasia (black arrows) Teaching points Nuclear stress testing is typically performed as part of the pre-renal transplantation evaluation.8 Review of the raw planar projection images allowed for the identification of Tc-99m uptake in the region of the thyroid and parathyroid gland in this patient. Previous reports documenting the incidental findings of parathyroid uptake following SPECT MPI have also emphasized the importance of reviewing the raw planar projection data.9,10 The presence of uptake in this region should prompt biochemical evaluation for thyroid and parathyroid abnormalities. In the case of hyperparathyroidism, elevated calcium and PTH levels are diagnostic. When primary hyperparathyroidism is suspected, preoperative Tc-99m Sestamibi planar and SPECT scintigraphy can demonstrate the location of an abnormal gland and help guide the necessary operative intervention.11 Secondary hyperparathyroidism can result from vitamin D deficiency or, as in this patient, from ESKD. In cases of secondary hyperparathyroidism resulting from ESKD, initial management includes phosphate binders for phosphate levels persistently > 5.5 mg/dL, vitamin D for patients with vitamin D deficiency or severe hypocalcemia, and calcitriol for persistently elevated (150 to 200 pg/mL) or rising PTH levels. Ultimately, kidney transplantation is required for definitive correction of mineral bone disease and secondary hyperparathyroidism associated with ESKD. Case 4 A 73-year-old woman with chronic kidney disease stage 3, atrial fibrillation, and hypertension is currently being evaluated for a neck mass which has gradually increased in size over the past 3 months. She has also experienced worsening dysphagia to both solids and liquids as well as hoarseness. An ultrasound of the neck obtained one month ago revealed the presence of a left thyroid lobe mass extending caudally into the upper mediastinum and laterally into the neck with infiltration of the left sternocleidomastoid muscle. The mass also partially encases the left common carotid artery and left internal jugular vein. Fine needle aspiration of the mass was performed, and the histologic specimen was classified as Bethesda 6 (malignant). She was referred to our institution for further evaluation of the neck mass. A CT with contrast of the chest showed a 6.6 × 5.3 cm mass originating from the left lobe of the thyroid gland (Figure 4A) with extension into the mediastinum. Multiple bilateral lung nodules measuring 4–14 mm were also seen. An open thyroid biopsy later confirmed the diagnosis of anaplastic thyroid carcinoma. The patient underwent a staging whole-body FDG-PET. Notable cardiac findings included a hypermetabolic pericardiophrenic lymph node, cardiomegaly, coronary atherosclerosis, and marked focal uptake (maximum SUV = 21.4) in the right atrium (Figure 4B). Extra-cardiac findings included focal uptake within multiple lung nodules, as well as multiple hypermetabolic lymph nodes located in the hilum of lung, mediastinum, and abdomen. Abnormal uptake was also noted within the soft tissues of bilateral hips and left posterior fourth rib. Given the advanced stage of the thyroid carcinoma (stage IV), she elected to undergo palliative radiation therapy for the neck mass.Figure 4 A CT scan of the chest with contrast, at the level of the neck. Imaging demonstrates the presence of a 6.6 × 5.3 cm mass (red arrow) originating from the left lobe of the thyroid gland. There is extension of the mass into the superior mediastinum. B. FDG-PET scan with a four-chamber cardiac view. Notable cardiac findings seen in this view included a hypermetabolic pericardiophrenic lymph node (blue arrow) and a right atrial metastatic lesion (white arrow) Teaching points FDG-PET imaging can be used to detect metabolically active lesions during oncologic evaluation. The cardio-oncologic findings seen on PET imaging in this case were notable for a hypermetabolic pericardiophrenic lymph node and a large right atrial metastatic lesion. The classification of cardiac neoplasms includes primary or secondary tumors (metastases). Generally, cardiac metastases are far more common than primary cardiac tumors and indicate the presence of an advanced stage or aggressive extra-cardiac neoplasm.12 Clinically, cardiac metastases usually present without symptoms, but may occasionally cause dyspnea or chest pain.13 Therefore, it is plausible that this patient could have initially presented following a PET scan for a cardiovascular indication. In such a case, a thorough evaluation of all PET scan slices is warranted to detect the presence of cardiac and extracardiac metastases. However, it should be noted that PET scans performed for cardiac indications are typically limited to the thoracic cavity and repeat imaging with a whole-body scan is warranted. Case 5 A 73-year-old woman with a history of presumed chronic pulmonary thromboembolism presents to our institution as a transfer from an outside hospital for hemoptysis and acute hypoxemic respiratory failure requiring intubation. One year prior to this admission, the patient underwent a CT angiogram for shortness of breath following a drive from Alabama to Texas. It revealed a pulmonary embolus completely filling and obstructing the right main pulmonary artery. During the past year, she was treated with multiple direct oral anticoagulants, but all were discontinued due to an increasing clot burden. More recently, warfarin was initiated for anticoagulation, but the patient has continued to worsen from a respiratory standpoint. Her vital signs were notable for a blood pressure of 124/59 mmHg, heart rate of 57 bpm, temperature of 98.4 F, and oxygen saturation of 100% on 40% oxygen with mechanical ventilation. A repeat CT angiogram of the chest revealed a thromboembolus occluding the main pulmonary artery with extension into the segmental and subsegmental vessels of the right lung (Fig. 5A–B). Pulmonary infarcts were also present in the periphery of the right lung. The clot further extended into the right ventricular outflow tract (RVOT). A transthoracic echocardiogram did not show evidence of right ventricular dysfunction but was notable for a right ventricular systolic pressure of 61 mm Hg. Bilateral lower extremity ultrasound was negative for deep vein thrombosis.Figure 5 A CT pulmonary angiogram at the level of the right main pulmonary artery. There is extension of the mass into the right segmental pulmonary artery (red arrow). B CT pulmonary angiogram at the level of the main pulmonary artery. The mass extends completely through the main pulmonary artery (blue arrow). C FDG-PET scan revealing the presence of a hypermetabolic tumor thrombus (red arrows) and hypometabolic bland thrombus (black arrow) in the main and right pulmonary arteries. Post right-sided pleurodesis inflammatory plaques are incidentally seen (blue arrows) Given the expanding size of the RVOT mass in the setting of adequate anticoagulation, an angiosarcoma of the pulmonary artery was suspected. FDG-PET scan revealed the presence of hypermetabolic intravascular mass (maximum SUV = 11.27 in the right ventricle) seen throughout the right pulmonary vasculature beginning at the RVOT and extending through the main pulmonary artery to the right upper, middle, and lower lobar arteries (Figure 5C). A mix of metabolically inactive and active thrombi were also seen in the main pulmonary artery, depicted by the black and red arrows within Figure 5C. No hypermetabolic metastatic lesions were seen. Incidental post pleurodesis inflammatory uptake was also noted (blue arrows Figure 3C). The patient subsequently underwent a pulmonary angiogram with biopsy of the mass. Pathology results were notable for a spindle cell angiosarcoma involving the RVOT. Teaching points Angiosarcomas involving the RVOT are associated with an extremely poor prognosis due to their aggressive nature.14,15 Because angiosarcomas can involve the right side of the heart or RVOT, presenting symptoms commonly include dyspnea and chest discomfort.16 At the time of diagnosis, metastases are typically present and often involve the lung.14,16 Angiosarcomas rapidly progress and culminate in death within weeks to months because of hemodynamic compromise (e.g., valvular obstruction), local invasion, or metastatic spread. Thus, early diagnosis is essential. Cardiac angiosarcomas pose a particular diagnostic challenge as their appearance on imaging can mimic pulmonary emboli.17 Thus, conventional imaging with transesophageal echocardiography, CT, and cardiac magnetic resonance imaging with gadolinium contrast are of little utility in distinguishing malignant from non-malignant lesions. However, FDG-PET has shown potential in differentiating benign from malignant disease.18,19 In a recent study involving 38 patients undergoing FDG-PET with malignant primary cardiac neoplasms, the majority of which were cardiac angiosarcomas, a maximum SUV at a minimum threshold of 3.44 provided a 100% sensitivity and 92% specificity for the detection of malignant neoplasms.20 Tissue biopsy ultimately provides definitive diagnosis. Treatment is complete resection, often with neoadjuvant and postoperative chemotherapy. Author contributions All authors had full access to the data when designing and drafting the manuscript. Disclosures All authors have no disclosures in relation to this manuscript. This case does not include any PHI and is exempt from an IRB protocol at this institution. Funding None. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Hawman PC Haines EJ The cardiofocal collimator: A variable-focus collimator for cardiac SPECT Phys Med Biol 1994 39 3 439 450 10.1088/0031-9155/39/3/011 15551592 2. Dorbala S Ananthasubramaniam K Armstrong IS Chareonthaitawee P DePuey EG Einstein AJ Single photon emission computed tomography (SPECT) myocardial perfusion imaging guidelines: Instrumentation, acquisition, processing, and interpretation J Nucl Cardiol 2018 25 5 1784 1846 10.1007/s12350-018-1283-y 29802599 3. Williams KA Hill KA Sheridan CM Noncardiac findings on dual-isotope myocardial perfusion SPECT J Nucl Cardiol 2003 10 4 395 402 10.1016/S1071-3581(03)00524-5 12900744 4. Kan H van der Zant FM Wondergem M Knol RJJ Incidental extra-cardiac findings on 13N-ammonia myocardial perfusion PET/CT J Nucl Cardiol 2017 24 6 1860 1868 10.1007/s12350-017-0824-0 28390039 5. Saab R, Farag A, White S, Hage FG, Bhambhvani P. Artifacts and Incidental Findings on Myocardial Perfusion Imaging. In: Hage FG (ed) Myocardial Perfusion Imaging (MPI): Performance, Potential Risks and Outcomes. Nova Science Publishers. 2018. ISBN: 978-1-53613-476-6. 6. McWilliams A Tammemagi MC Mayo JR Roberts H Liu G Soghrati K Probability of cancer in pulmonary nodules detected on first screening CT N Engl J Med 2013 369 10 910 919 10.1056/NEJMoa1214726 24004118 7. MacMahon H Naidich DP Goo JM Lee KS Leung ANC Mayo JR Guidelines for management of incidental pulmonary nodules detected on CT images: from the Fleischner Society 2017 Radiology 2017 284 1 228 243 10.1148/radiol.2017161659 28240562 8. Ives CW AlJaroudi WA Kumar V Farag A Rizk DV Oparil S Prognostic value of myocardial perfusion imaging performed pre-renal transplantation: post-transplantation follow-up and outcomes Eur J Nucl Med Mol Imaging 2018 45 11 1998 2008 10.1007/s00259-018-4068-2 29882159 9. Iagaru A Hachamovitch R Colletti PM Wassef H Demonstration of an ectopic mediastinal parathyroid adenoma on Tc-99m sestamibi myocardial perfusion scintigraphy J Nucl Cardiol 2006 13 5 719 721 10.1016/j.nuclcard.2006.06.125 16945752 10. Chamarthy M Travin MI Altered biodistribution and incidental findings on myocardial perfusion imaging Semin Nucl Med 2010 40 4 257 270 10.1053/j.semnuclmed.2010.03.005 20513448 11. Wilhelm SM Wang TS Ruan DT Lee JA Asa SL Duh QY The American association of endocrine surgeons guidelines for definitive management of primary hyperparathyroidism JAMA Surg 2016 151 10 959 968 10.1001/jamasurg.2016.2310 27532368 12. Butany J Leong SW Carmichael K Komeda M A 30-year analysis of cardiac neoplasms at autopsy Can J Cardiol 2005 21 8 675 680 16003450 13. Yusuf SW Bathina JD Qureshi S Kaynak HE Banchs J Trent JC Cardiac tumors in a tertiary care cancer hospital: clinical features, echocardiographic findings, treatment and outcomes Heart Int 2012 7 e4 10.4081/hi.2012.e4 22690297 14. Omair M Calafiore P Lim R McGiffin D Farouque O Jones E Primary angiosarcoma-a rare cause of right ventricular outflow tract obstruction: case report and literature review CASE 2019 3 6 284 287 10.1016/j.case.2019.08.003 32002486 15. Hohmann C Pfister R Ney S Fink L Bunck AC Michels G Pulmonary angiosarcoma: a rare cause of right ventricular outflow tract obstruction J Cardiovasc Med 2021 22 8 664 667 10.2459/JCM.0000000000001105 16. Ge Y Ro JY Kim D Kim CH Reardon MJ Blackmon S Clinicopathologic and immunohistochemical characteristics of adult primary cardiac angiosarcomas: analysis of 10 cases Ann Diagn Pathol 2011 15 4 262 267 10.1016/j.anndiagpath.2011.02.007 21546292 17. Ananthasubramaniam K Farha A Primary right atrial angiosarcoma mimicking acute pericarditis, pulmonary embolism, and tricuspid stenosis Heart 1999 81 5 556 558 10.1136/hrt.81.5.556 10212178 18. Dhull VS Sharma P Mukherjee A Jana M Bal C Kumar R 18F-FDG PET-CT for evaluation of cardiac angiosarcoma: a case report and review of literature Mol Imaging Radionucl Ther 2015 24 1 32 36 10.4274/mirt.02486 25800597 19. Shao D Wang SX Liang CH Gao Q Differentiation of malignant from benign heart and pericardial lesions using positron emission tomography and computed tomography J Nucl Cardiol 2011 18 4 668 677 10.1007/s12350-011-9398-4 21655905 20. Meng J Zhao H Liu Y Chen D Hacker M Wei Y Assessment of cardiac tumors by 18F-FDG PET/CT imaging: Histological correlation and clinical outcomes J Nucl Cardiol 2021 28 5 2233 2243 10.1007/s12350-019-02022-1 31933156
PMC009xxxxxx/PMC9548422.txt	==== Front J Behav Med J Behav Med Journal of Behavioral Medicine 0160-7715 1573-3521 Springer US New York 36215000 359 10.1007/s10865-022-00359-6 Article The impact of Dietary Weight loss, Aerobic Exercise, and Daylong Movement on Social Cognitive Mediators of Long-term Weight loss http://orcid.org/0000-0002-5527-1698 Fanning Jason [email protected] 1 Nicklas Barbara 2 Furlipa Joy 1 Rejeski W. Jack 1 1 grid.241167.7 0000 0001 2185 3318 Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC USA 2 grid.241167.7 0000 0001 2185 3318 Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC USA 10 10 2022 2023 46 3 499508 18 3 2022 17 8 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. This report contrasts the impact of a dietary weight loss intervention (WL) paired with aerobic exercise (EX) and/or sitting less and moving throughout the day (SL) on self-efficacy for walking (hereafter walking self-efficacy) and satisfaction with physical functioning (hereafter satisfaction). Additional analyses examined dose-response associations between change in weight and changes in these key outcomes. Older adults (N = 112; age = 70.21\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\pm$$\end{document}4.43) were randomized to 6 months of WL+EX, WL+SL, or WL+EX+SL followed by a 12-month maintenance period. All groups reported increases in walking self-efficacy at month 6 with greater improvements in WL+EX and WL + EX+SL. Only WL+SL demonstrated improved walking self-efficacy at month 18. All conditions demonstrated improved satisfaction scores at both time points. Changes in walking self-efficacy and satisfaction were negatively associated with change in weight over the 6-month intervention and after the maintenance period. These results support the utility of WL + SL for improving key social cognitive outcomes in aging. Keywords Obesity Behavioral weight loss Physical activity Aging Behavioral maintenance http://dx.doi.org/10.13039/100000049 National Institute on Aging R01 AG051624 P30 AG21332 Rejeski W. Jack issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction Obesity in older adults constitutes an enormous burden on the health care system and society in that it predisposes individuals to physical disability, a host of chronic diseases, and premature mortality (Gill et al., 2015; Houston et al., 2009; Rejeski et al., 2010). While it is well-recognized that state-of-the-art behavioral weight loss programs include physical activity to sustain maintenance of lost weight (Bergouignan et al., 2016; Physical Activity Guidelines Advisory Committee 2018; Piercy et al., 2018), in this context it is unclear how physical activity should be prescribed for older adults, since structured exercise often leads to a compensatory increase in sedentary behavior (Thompson et al., 2014) and the exercise behavior is rarely sustained upon termination of formal treatment (McEwan et al., 2022). In a recently completed randomized-controlled trial of weight regain in older adults with obesity (Fanning et al., 2022), we compared caloric restriction for behavioral weight loss (WL) when it is coupled with one of three physical activity interventions: structured exercise (WL + EX), sitting less and moving more across the day (WL + SL), or a treatment involving both exercise and moving across the day (WL + EX + SL). Participants engaged in a 6-month “intensive” intervention comprising weekly in-person group meetings and a suite of self-monitoring tools. This was followed by a 12-month minimal contact period. All groups demonstrated a significant 6-month reduction in body weight, with no group differences. Groups that received SL improved total activity time and those who received EX improved moderate-to-vigorous activity time. Over the 12-month follow-up period, where there was minimal contact to examine weight regain, those who received WL + EX demonstrated greater weight regain relative to WL + SL. This secondary analysis examines the extent to which two social cognitive constructs that are central to the promotion of physical activity and quality of life in older adults—self-efficacy for walking and satisfaction with physical functioning—changed as a function of the three treatments. Finally, because the dose (i.e., amount) of weight loss has been found to be directly related to change in numerous health outcomes (Atukorala et al., 2016; Georgoulis et al., 2022; Wang et al., 2022) we also examine the associations between change in each outcome (self-efficacy for walking, satisfaction with physical functioning) and change in body weight. A strong body of evidence indicates that well-designed structured exercise interventions increase older adults’ self-efficacy and satisfaction with their physical functioning, and these are important social cognitive outcomes closely linked with quality of life and health behavior change (Fanning, Walkup, et al., 2018; Katula et al., 2004; McAuley & Blissmer, 2000). However, the effects of these interventions quickly dissipate with the end of formal program support (McAuley et al., 1993, 2011). As a result, some researchers have worked to integrate physical activity into the lifestyle of older adults with a focus on accumulating recommended levels of physical activity throughout the day via an array of enjoyable activities, hereafter referred to as “daylong movement” (Fanning et al., 2020, 2022 Sallis et al., 2006). It is not surprising that long-term adherence to dietary weight loss and structured exercise is poor (McEwan et al., 2022). Both behaviors are highly complex and subject to dynamic physiological, psychological, social, and environmental influences. Social cognitive theory (Bandura 1986, 1997) outlines several constructs that drive both uptake and maintenance of challenging behaviors. The central construct in social cognitive theory is self-efficacy, which consistently emerges as a key cause and consequence of older adults’ activity (McAuley & Blissmer, 2000) and eating behaviors (Ames et al., 2012) and can be defined as an individual’s perceived ability to execute a very specific course of action (Bandura, 1997). Importantly, self-efficacy is modifiable through well-designed behavioral interventions—especially those that include goals that progress in difficulty, provide immediate and specific feedback, and that are social in nature (McAuley et al., 2011). In addition to driving adoption and maintenance of targeted eating and activity behaviors, self-efficacy perceptions are also closely related to numerous valued outcomes in aging including health-related quality of life (McAuley et al., 2006). A second social cognitive construct that is informed by self-efficacy perceptions, affects quality of life, and drives behavioral uptake and maintenance is outcome expectations (Bandura, 2004; Rejeski et al., 2001). In the context of a weight loss and physical activity intervention, weight loss and enhanced activity contribute to better physical functioning and in turn feelings of satisfaction with one’s physical functioning (hereafter referred to as satisfaction). As a result, the individual is likely to develop positive attitudes toward weight loss and activity participation. Deficits in satisfaction are associated with physical disability and limitations to daily activities (Blalock et al., 1988; Katz & Neugebauer, 2001) and well-designed weight loss and exercise trials consistently produce improvements in satisfaction (Brawley et al., 2012; Rejeski et al., 2014). We previously demonstrated that a 6-month group-mediated intervention targeting weight loss paired with structured walking exercise among older adults produced significant improvements in self-efficacy for walking (hereafter referred to as walking self-efficacy) for extended durations and in satisfaction versus a weight loss only condition. These effects persisted across a one-year period of minimal contact (Fanning, Walkup, et al., 2018). In recent years, increased attention in the physical activity literature has been directed toward increasing physical activity via daylong movement as compared to structured exercise (Physical Activity Guidelines Advisory Committee 2018). A daylong movement approach to activity promotion is one that emphasizes achieving physical activity recommendations through frequent bouts of activity; indirectly breaking up sustained sitting time. For instance, one might engage in active commuting, chores around the home, or walking the dog while self-monitoring progress toward a daily step goal (Nicklas et al., 2014). Such an approach may present one method for addressing the limitations of structured exercise interventions. For example: (a) exercise programs do not train individuals to flexibly alter activity regimens in the face of boredom or daily barriers; (b) participation in structured exercise often contributes to compensatory sitting and reductions of activities of daily living; and (c) exercise is often not intrinsically enjoyable and is therefore difficult to sustain once behavioral supports are removed on completion of a program (Bonomi et al., 2013; Deci & Ryan, 2008; Martin et al., 2011; Melanson et al., 2013; Redman et al., 2009). This approach to activity promotion is also supported by the most recent Physical Activity Guidelines for Americans, which emphasizing moving more and more often and removed a recommended minimum bout duration for physical activity (Piercy et al., 2018). In one 12-week pilot study, older adults with chronic pain were randomized to receive dietary weight loss in combination with a daylong movement intervention or to a waitlist control (Fanning et al., 2020). Those who received the active intervention demonstrated moderate improvements in walking self-efficacy and large improvements in satisfaction (Fanning et al., 2021). To date, there are no data comparing dietary weight loss combined with either structured exercise and/or daylong movement on walking self-efficacy or satisfaction. Moreover, few researchers have published on the relationships between changes in these key constructs and changes in weight in the context of a weight loss intervention for older adults. The primary purpose of this secondary analysis is to investigate changes in walking self-efficacy and satisfaction after the 6-month intensive phase of the intervention. Additionally, we will investigate changes in self-efficacy and satisfaction at the final 18-month assessment, which followed 12 months of minimal contact with the research team. Notably, we have previously reported that participants in each condition lost a similar amount of weight over 6 months, but those in WL + EX regained significantly more weight during the 6- to 18-month maintenance phase as compared to WL + SL (Fanning et al., 2022). Because of mounting evidence related to the favorable dose-response effects of weight loss on health outcomes (Atukorala et al., 2016; Georgoulis et al., 2022; Wang et al., 2022), we also examine the associations between weight loss and change in these outcomes. The specific hypotheses included the following. First, at 6 months, all three treatment groups would experience improvement in each outcome. However, because WL + EX and WL + EX + SL trained in walking for exercise, we expect improvements in self-efficacy for walking to be greater in these groups relative to WL + SL. Second, as WL + SL demonstrated the best maintenance of weight loss over the 12-month minimal contact period (Fanning et al., 2022), we expect better maintenance of walking self-efficacy and satisfaction across this period relative to WL + EX and WL + EX + SL. Methods Participants The Empowered with Movement to Prevent Obesity and Weight Regain (EMPOWER) study was an 18-month, three-group, single-blind randomized trial (NCT02923674). Study design and detailed methods and CONSORT for the EMPOWER trial were previously published (Fanning et al., 2022). Participants were recruited in six waves between 2016 and 2019 from Forsyth County and surrounding areas in North Carolina. The first five waves completed the 6-month intensive phase of the intervention prior to the onset of the COVID-19 pandemic in the United States and the implementation of local stay-at-home orders. As such we have restricted our analyses to these participants. Eligible participants were aged 65–85 years, classified as having obesity with a body mass index (BMI) of 30–45 kg/m2; not participating in regular resistance training and/or > 20 min/day of other structured exercise in past 6 months; nonsmoking for at least 1 year; <5% weight change in past 6 months; and no insulin-dependent or uncontrolled diabetes, osteoporosis as verified via dual-energy x-ray absorptiometry scan, cognitive impairment (i.e., Montreal Cognitive Assessment < 22), clinical depression, anemia, heart disease, cancer, liver, renal, or chronic pulmonary disease, uncontrolled hypertension, major physical impairment, or any contraindication for weight loss or exercise. Additionally, participants were asked about their access to a personal smartphone device and willingness to use it for the study. Those without a device were given one for the duration of the study (18% of all randomized participants). Randomization In total, 1,655 participants were pre-screened via telephone, 183 participants were randomized in a 1:1:1 fashion to one of the three study treatment arms: WL + EX, WL + SL, or WL + EX + SL. A total of 151 participants were randomized in the first 5 waves of EMPOWER. Interventions During the initial 6-month intensive intervention phase, all participants met once weekly in group-mediated dietary weight loss sessions. Each participant received a Fitbit Alta activity monitor, which was paired with a custom EMPOWER “Companion” smartphone app (see Fig. 1 for example screens). This app displayed condition-specific feedback on physical activity (see below), reinforced success through group-specific “mastery” badges (Fanning et al., 2017) and facilitated contact between group members and group leaders during the week (Fanning et al., 2022; Fanning, Opina, et al., 2018). After the initial intensive period, participants transitioned to a 12-month maintenance period, which included a 3-month transition phase wherein participants met twice monthly, and a 9-month no-contact period. Participants retained access to study technologies throughout the full 18-month study period. Fig. 1 Example EMPOWER Companion app screens. The bar across the bottom depicts patterns of Fitbit-based non-movement (blue) and movement (green/teal). For those who received the exercise component, sporadic movement in bouts < 10 min are displayed in teal and sustained movement in bouts of at least 10 min are displayed in green Dietary Weight Loss (WL) All participants aimed to achieve 7 − 10% weight loss from baseline body mass through a weekly caloric restriction goal of approximately 400 kcal/day from weight maintenance requirements. Participants aimed to consume approximately 25–30% of energy from protein, 20–35% from fat, and 45–55% from carbohydrates, and participants tracked progress toward daily dietary goals via paper or digital food log. To support adoption and adherence to these goals, participants met each week in the first 6 months of the program in small peer groups led by a behavioral interventionist and registered dietician. These sessions were designed using principles of social cognitive theory (Bandura, 1997) and group dynamics (Brawley et al., 2000) with an emphasis placed on developing self-regulatory skills, strengthening social support, developing knowledge and awareness, and experiencing the interplay between physical activity, mindfulness, and eating. The content of these sessions was further tailored to each group’s unique activity recommendation (see reference (Fanning, Opina, et al., 2018) for details on the weight loss component of the interventions). Aerobic Exercise (EX) Participants randomized to the WL + EX and WL + EX + SL conditions engaged in walking at a moderate-to-vigorous intensity on 4–5 days per week (65–70% heart rate reserved as calculated from a graded maximal exercise test). This was accomplished primarily as supervised treadmill walking. Duration of exercise progressed to 40–50 min by the sixth week of the program. Each session completed with a 3–5-minute cooldown followed by 5 min of large muscle flexibility stretches. During the initial 6-month intensive phase of EMPOWER, participants aimed to attend supervised exercise sessions at least 3 times weekly, with the remaining sessions conducted in the home or community. Participants received guidance on self-monitoring exertion using Rating of Perceived Exertion with a target rating of 13–15 (Borg, 1973). As a self-monitoring tool, participants self-reported exercise by selecting “I exercised” within the Companion app. Additionally, given the focus on sustained aerobic exercise, the participant’s Companion app highlighted activity bouts of at least 10 min in two ways. First, a timeline bar displayed on the bottom of the screen depicted patterns of movement throughout the day in near real time based upon data from the Fitbit device. Inactive minutes (0 steps) were displayed in blue, non-bouted minutes of stepping activity (i.e., those lasting less than 10 min) were marked in pale green, and bouts lasting at least 10 min were marked in bright green. Additionally, the app displayed minutes spent in activity bouts of at least 10 min. See (Fanning et al., 2022; Fanning, Opina, et al., 2018) for more information. SitLess (SL) Those randomized to the WL + SL and WL + EX + SL conditions aimed to increase the amount of time they spent in physical activity while indirectly breaking up sitting time by engaging in frequent bouts of activity. In addition to weight loss, the SL group content focused on finding ways to engaging in light and moderate-to-vigorous intensity lifestyle activities across the day. This was reinforced by several feedback mechanisms within the Companion app. As with the EX condition, SL participants were instructed to view their patterns of activity using the timeline bar within the app. However, this timeline bar simply marked all movement (i.e., minutes with > 0 steps) as green, and all non-movement minutes in blue. Participants were instructed to attempt to achieve a “tree rings” profile. That is, participants sought to have stripes of green evenly dispersed throughout the day. This was further supported by a “periodic step goal.” Participants aimed to increase their daily step goal by up to 25% each week, and these goals were set in collaboration with the group leader with a maintenance limit of 10,000 daily steps. To disincentivize engaging in a single bout of sustained walking followed by prolonged sedentary behavior, participants could earn up to 45% of their daily steps prior to 12:00pm, 45% could be earned between 12:00pm and 5:30pm, and 45% could be earned after 5:30pm. Thus, achieving a daily step goal required movement during each period of the day. See (Fanning et al., 2022; Fanning, Opina, et al., 2018) for more detail. Outcomes Blinded research staff collected measures at baseline prior to randomization and again at 6 months. Body weight was assessed on the same calibrated scale within the clinical research center. Satisfaction with physical functioning was assessed using a 6-item scale developed originally by Ray and colleagues (Ray et al., 1996). Individuals were cued to rate their satisfaction with various components of physical function. Example items include “currently, how satisfied are you with your overall level of physical fitness?” or “currently, how satisfied are you with your overall level of energy?”. Responses are provided on a 7-point scale ranging from − 3 (very dissatisfied) to + 3 (very satisfied), and the final satisfaction score is an average of these 7 items. Reboussin and colleagues (2000) demonstrated that all six items loaded on a single dimension with a Cronbach alpha of 0.94. Rejeski and colleagues demonstrated that the satisfaction had a 1-3-week test-retest reliability of 0.73, and we have previously demonstrated it is responsive to change in the context of physical activity and weight loss randomized trials (Fanning et al., 2021; Fanning, Walkup, et al., 2018). Walking self-efficacy was assessed using an 8-item scale that queried participants on their perceived ability to walk at a moderate pace without stopping for 5, 10, 15, 20, 25, 30, 35, and 40 min. Responses were provided on an 11-point scale such that 0 indicated “not at all confident” and 10 indicated “high confidence”. The final walking self-efficacy score is computed as an average of these 8 items. This scale was developed based on Bandura’s methodology (1986, 2006) and we have previously demonstrated it is amenable to change in the context of a physical activity weight loss intervention (Fanning et al., 2021; Fanning, Walkup, et al., 2018). Statistical Analyses Descriptive statistics, including mean and standard deviation for continuous variables and N (%) for categorical variables, are presented to describe the sample at baseline. To determine whether changes in satisfaction and self-efficacy differ by intervention assignment, we first conducted separate analyses of covariance, including group assignment as a between-subjects factor, the outcome of interest (self-efficacy or satisfaction) at 6- or 18-months as the dependent variable, and the baseline value of the dependent variable and participant sex as covariates. Post-hoc paired samples t-tests conducted within each group were used to investigate whether scores changed over time. Levene’s test was utilized to verify homogeneity of variances and normality of residuals was confirmed via skewness Z scores. Raw walking self-efficacy data were negatively skewed, which was improved by applying a reflected natural log transformation to measures at each timepoint. The sign for each resulting regression or correlation coefficient has been inverted in text to assist in interpretation. Finally, to examine whether change in self-efficacy and satisfaction were associated with change in weight, we conducted a series of Pearson correlations between residualized change in body weight and residualized change in self-efficacy and satisfaction at month 6 and 18, each accounting for baseline values. Within each analysis, significance was established at p \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\le$$\end{document} 0.05. Additionally, as a sensitivity analysis, we repeated all analyses following multiple imputation with five imputations across the waves of participants who received EMPOWER prior to COVID-related stay-at-home orders. As interpretation was not meaningfully altered by this approach, results from original non-imputed analyses are presented herein. Results Participant Characteristics . In total, 112 participants engaged in the first 5 waves of EMPOWER and provided data at baseline, month 6, and month 18. Participant characteristics at baseline are displayed in Table 1. The average age at baseline was 70.21 ± 4.43 years. The majority of participants were white (75.0%), female (75%), and had obesity (35.44\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\neg \pm$$\end{document}3.75 kg/m2). A table comparing demographic characteristics and baseline self-efficacy and satisfaction scores in those with and without complete data is provided in Supplemental Table 1. Note there were no statistically significant differences identified in these comparisons. Table 1 Participant characteristics. Notes: M = mean; SD = standard deviation; BMI = body mass index, kg/m2; Peak VO2 (mL/kg/min), self-efficacy and satisfaction scores are baseline values; WL = dietary weight loss; EX = aerobic exercise;aComplete peak VO2 data available on 104 participants (WL + EX n = 36, WL + EX + SL n = 30, WL + SL n = 38) WL + EX (n = 40) WL + SL (n = 33) WL + EX + SL (n = 39) All (N = 112) Age; M(SD) 70.49 (4.08) 69.66 (5.04) 70.54 (4.15) 70.21 (4.43) BMI; M(SD) 35.76 (3.87) 35.77 (3.73) 34.66 (3.62) 35.44 (3.75) Race; n(%) White 33 (82.5) 28 (71.8) 23 (69.7) 84 (75) Black 5 (12.5) 10 (25.6) 10 (30.3) 25 (22.3) More than one 2 (5.0) 1 (2.6) 0 (0.0) 3 (2.7) Sex; n(%) Male 9 (22.5) 11 (28.2) 8 (24.2) 28 (25) Female 31 (77.5) 28 (71.8) 25 (75.8) 84 (75) Hypertension; n(%) 28 (70) 22 (66.7) 24 (61.5) 74 (66.1) Diabetes; n(%) 3 (7.5) 4 (12.1) 7 (17.9) 14 (12.5) Arthritis; n(%) 27 (67.5) 25 (75.8) 26 (66.7) 78 (69.6) Peak VO2; M (SD)a 19.3 (3.1) 20.6 (4.0) 19.6 (5.1) 19.8 (4.2) Self-Efficacy; M(SD) 6.7 (2.11) 6.11 (3.11) 7.22 (2.44) 6.65 (2.61) Satisfaction; M(SD) -0.93 (1.52) -0.91 (1.54) -0.40 (1.53) -0.77 (1.54) Intervention-related changes in self-efficacy for walking and satisfaction with physical function Marginal means for each ANCOVA model, alongside results of within-group post-hoc paired t-tests are found in Table 2; Fig. 2. An ANCOVA controlling for baseline values and sex revealed a significant main effect for group assignment on transformed self-efficacy for walking scores at month 6; F(2,107) = 6.137, p < .05, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\eta }^{2}$$\end{document}=0.103. Post-hoc analyses indicated that both WL + EX and WL + SL+EX demonstrated significantly higher self-efficacy at month 6 relative to WL + SL (ps < 0.05). Notably, paired t-tests indicated that all groups improved significantly from baseline to month 6 (ps < 0.05). Regarding satisfaction with function, ANCOVA models revealed no significant group effects at month 6. A series of paired t-tests revealed significant improvements in satisfaction scores in each group from baseline to month 6 (ps < 0.05). Table 2 Marginal means [M (95%CI)] for self-efficacy for walking and satisfaction with function, adjusted for baseline values and sex. Notes: due to a negative skew and heterogeneous variances, self-efficacy scores were reflected, and log transformed. Back-transformed scores are presented here. a=significant within-group change from baseline to month 6; b=significant within-group change from baseline to month 18; c=significant within-group change from month 6 to 18; WL = dietary weight loss; EX = aerobic exercise; SL = the SitLess daylong movement program Self-Efficacy Satisfaction with Function Month 6 Month 18 Month 6 Month 18 WL + EX 9.41 (9.07, 9.69)a 8.19 (7.45, 8.78)c 0.83 (0.43, 1.23)a 0.14 (-0.36, 0.64)bc WL + SL + EX 9.43 (9.06, 9.73) a 8.15 (7.30, 8.79)c 1.10 (0.65, 1.54)a 0.50 (-0.05, 1.05)bc WL + SL 8.57 (8.05, 9.00) a 8.35 (7.64, 8.91)b 0.71 (0.30, 1.11)a 0.12 (-0.38, 0.63)bc Fig. 2 Marginal means for self-efficacy for walking (top panel) and satisfaction with function (bottom panel), adjusted for baseline values and sex. Note: self-efficacy for walking values were reflected and transformed due to non-normality and heterogeneous variances; the data presented here have been back transformed Changes in self-efficacy for walking and satisfaction with physical function during the minimal contact phase At month 18, an ANCOVA revealed there was no longer a significant difference in self-efficacy between conditions. A series of paired t-tests indicated that WL + EX and WL + EX + SL both decreased significantly from 6 to 18 months (ps < 0.05) such that scores at month 18 were not significantly different from baseline. WL + SL did not decrease during this period, and scores at 18 were significantly higher than baseline (p < .05). Regarding satisfaction with function, there was no significant difference between groups at month 18. Paired t-tests revealed significant improvements in satisfaction scores in each group from baseline to month 18 (ps < 0.05), though scores did decrease during the maintenance period (ps < 0.05). Relationships between changes in body weight and change in self-efficacy for walking and satisfaction with physical function Relationships between residualized change in body weight at month 6 and 18 and residualized change in self-efficacy and satisfaction are depicted in Fig. 3. and Table 3. Change in body weight following the intensive 6-month intervention period was negatively and weakly related to change in transformed walking self-efficacy (r = -.23, p < .05) and moderately, negatively associated with satisfaction (r =-.36, p < .05). These relationships strengthened at month 18 such that change in self-efficacy (r=-.43, p < .05) and satisfaction (r=-.54, p < .05) were both moderately negatively associated with change in body weight. Fig. 3 Relationships between residualized change in body weight, and self-efficacy for walking and satisfaction with function at 6 and 18 months Table 3 Correlations between residualized change in body weight and residualized change in self-efficacy for walking and satisfaction with physical functioning Residualized Change in Body Weight (Month 6) Residualized Change in Body Weight (Month 18) Residualized Change in Self-Efficacy for Walking − 0.23 − 0.43 Residualized Change in Satisfaction with Physical Function − 0.36 − 0.54 Discussion Our results support the first study hypothesis: regardless of group assignment, participants demonstrated improvements in self-efficacy and satisfaction following the 6-month intervention weight loss and physical activity intervention. Additionally, as expected, participants who received an exercise intervention focused on sustained walking demonstrated significantly better self-efficacy for walking relative to those who did not (WL + SL). The second study hypothesis was only partially supported: where both WL + EX and WL + EX + SL regressed to baseline levels of self-efficacy for walking by month 18, only WL + SL did not significantly decrease self-efficacy scores, sustaining a significant increase over baseline. Interestingly, counter to our hypotheses, all groups demonstrated maintenance in satisfaction scores. This is the first study to directly compare the impact of structured exercise and/or a program involving daylong movement on two key social cognitive outcomes associated with health behavior change and health-related quality of life in older adults. That a daylong movement program yielded significant improvements in self-efficacy and satisfaction is promising, since such an approach is likely to be more feasible and sustainable for a larger segment of the older adult population. As our data suggest, this is most evident once the intensive social and infrastructural supports of a structured intervention are removed. To this end, as we have previously published (Fanning et al., 2022), individuals who received WL + SL regained the least weight after the 6-month intensive intervention period. Finally, in support of our third hypothesis we demonstrated that weight loss during the initial 6-month intervention was inversely associated with change in self-efficacy and satisfaction. Perhaps more interesting was the finding that relationships between change in weight and change in walking self-efficacy and satisfaction strengthened at the 18-month time point. This followed 12 months of minimal contact wherein participants sought to sustain their weight loss without the structural benefits of the 6-month intervention period (e.g., weekly meetings with feedback from the intervention staff). One explanation for this effect may be that program-related weight loss resulted in individuals feeling more confident in and satisfied with their physical functioning. However, counter to this interpretation is evidence from a previous clinical trial (Fanning, Walkup, et al., 2018) demonstrating that participation in dietary weight loss plus exercise yields significantly better walking self-efficacy and satisfaction with function scores relative to a group who achieved their weight loss only via dietary means. More likely is that these relationships operate bidirectionally. This notion is supported by social cognitive theory wherein Bandura (1997) notes that better perceptions of self-efficacy and more positive outcome expectancies drive future participation in a behavior such as activity for weight management. Conversely, success resulting from this behavior drives improvements in self-efficacy to continue the behavior, and when that behavior results in notable physical and psychological outcomes (e.g., weight loss, improved mood), individuals are likely to expect future participation to yield similar benefits. Our findings suggest that these relationships may strengthen in the absence of more external forms of regulation, such as accountability to a coach or peers. Strengths and Limitations There are several notable strengths to this study. EMPOWER included a fairly long intervention period (6 months) and a year-long follow-up, providing highly valuable data on ratings of self-efficacy and satisfaction following cessation of the structured intervention period. It employed a novel intervention designed to promote the accumulation of physical activity throughout the day. Such an approach indirectly breaks up prolonged sedentary time and aligns closely with recent revisions to the Physical Activity Guidelines for Americans, which emphasize a “move more, more often” approach to achieving sufficient levels of activity and for combatting obesity (Piercy et al., 2018). Each condition was supported by an evidence-based mHealth app, which aimed to support self-efficacy through immediate and specific feedback, and we provided smartphone devices for participants who did not own a device. There are also several notable limitations that must be acknowledged. Due to the onset of the COVID-19 pandemic and associated stay-at-home orders, only 151 individuals were eligible to participate and 112 provided sufficient data for the present analysis. Of these individuals, 22.3% were Black, which is a lower percentage than the community in which the program was delivered 34.9%; (QuickFacts: Winston-Salem, North Carolina 2021), and 75% were female. This limits the generalizability of our findings and warrants replication in samples with greater male and non-White representation. Additionally, the design of this study neither permitted us to test mechanistic hypotheses, such as whether changes in weight loss and maintenance were driven by changes in walking self-efficacy or satisfaction, nor was there a no treatment control group for comparison. These represent exciting areas for future research for those conducting daylong movement interventions. Finally, we restricted our study sample to community-dwelling older adults with no contraindications to dietary weight loss or participation in physical activity. Additional work should investigate the health effects of a weight loss and daylong movement intervention among clinical populations who may benefit from more frequent activity such as those with diabetes or undergoing cancer treatment. Conclusion Perceptions of confidence in and satisfaction with one’s physical function are highly important outcomes for older adults. Self-efficacy and satisfaction with function are closely tied to the adoption and maintenance of health behaviors as well as perceptions of health-related quality of life. Our findings add to recent public health guidance that health promotion professionals should demonstrate flexibility in the ways in which physical activity is prescribed for older adults. While some may resonate with the experience of traditional structured exercise, many do not. For these individuals, programs focused on daylong movement may contribute to improved self-efficacy and satisfaction, which in turn is associated with both short-term weight loss and the maintenance of lost weight. Future work should focus on better understanding the key behavior change techniques required to promote the accumulation of physical activity as a means of obesity treatment and weight management in large and diverse populations. Tables. Acknowledgements We are thankful to our research team including Cheyenne Barnett, Jessica Sheedy, Beverly Nesbit, and Sherri Ford. We are also immensely grateful to all of our study participants. Author contributions Drs. Nicklas and Rejeski designed and conducted the trial and assisted in manuscript preparation; Dr. Fanning helped to design and conduct the trial and led manuscript preparation and data analysis; Joy Furlipa assisted in manuscript preparation. Funding The trial was funded by the National Institute on Aging (R01 AG051624; P30-AG21332). Conflict of interest The authors declare no conflicts of interest. Ethics approval, human and animal rights, and informed consent All procedures performed herein were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standard. Informed consent was obtained from all individual participants included in the study. Consent for publication N/A. Data Availability Data may be made available upon request at discretion of the authors. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Ames GE Heckman MG Grothe KB Clark MM Eating self-efficacy: Development of a short-form WEL Eating Behaviors 2012 13 4 375 378 10.1016/j.eatbeh.2012.03.013 23121791 Atukorala I Makovey J Lawler L Messier SP Bennell K Hunter DJ Is there a dose-response relationship between weight loss and symptom improvement in persons with knee osteoarthritis? Arthritis Care & Research 2016 68 8 1106 1114 10.1002/acr.22805 26784732 Bandura A Social foundations of thought and action 1986 Englewood Clifs, NJ Prentice Hall Bandura A Self-efficacy: The exercise of control 1997 New York, NY W. H. Freeman and Company Bandura A Health promotion by social cognitive means Health education & behavior 2004 31 2 143 164 10.1177/1090198104263660 15090118 Bandura A Guide for constructing self-efficacy scales Self-efficacy beliefs of adolescents 2006 Charlotte, NC Information Age Publishing 307 337 Bergouignan A Legget KT De Jong N Kealey E Nikolovski J Groppel JL Effect of frequent interruptions of prolonged sitting on self-perceived levels of energy, mood, food cravings and cognitive function International Journal of Behavioral Nutrition and Physical Activity 2016 13 1 1 12 10.1186/s12966-016-0437-z 26733186 Blalock SJ deVellis BM deVellis RF Sauter SH Self-evaluation processes and adjustment to rheumatoid arthritis Arthritis & Rheumatology 1988 31 10 1245 1251 10.1002/art.1780311005 Bonomi, A. G., Soenen, S., Goris, A. H. C., & Westerterp, K. R. (2013). Weight-loss induced changes in physical activity and activity energy expenditure in overweight and obese subjects before and after energy restriction. PLoS ONE, 8(3), e59641 Borg GA Perceived exertion: a note on “history” and methods Medicine and Science in Sports and Exercise 1973 5 2 90 93 10.1249/00005768-197300520-00017 Brawley LR Rejeski WJ Gaukstern JE Ambrosius WT Social cognitive changes following weight loss and physical activity interventions in obese, older adults in poor cardiovascular health Annals of Behavioral Medicine 2012 44 3 353 364 10.1007/s12160-012-9390-5 22773225 Brawley LR Rejeski WJ Lutes L A group-mediated cognitive behavioural intervention for increasing adherence to physical activity in older adults Journal of Applied Biobehavioral Research 2000 5 1 47 65 10.1111/j.1751-9861.2000.tb00063.x Deci, E. L., & Ryan, R. M. (2008). Self-determination theory: A macrotheory of human motivation, development, and health. In Canadian Psychology (Vol. 49, pp. 182–185) Fanning, J., Roberts, S., Hillman, C. H., Mullen, S. P., Ritterband, L., & McAuley, E. (2017). A smartphone “app”-delivered randomized factorial trial targeting physical activity in adults. Journal of Behavioral Medicine, 40(5), 712–729. 10.1007/s10865-017-9838-y Fanning, J., Opina, M. T., Leng, I., Lyles, M. F., Nicklas, B. J., & Rejeski, W. J. (2018). Empowered with Movement to Prevent Obesity & Weight Regain (EMPOWER): Design and methods. Contemporary Clinical Trials, 72, 35–42. 10.1016/j.cct.2018.07.010 Fanning, J., Walkup, M. P., Ambrosius, W. T., Brawley, L. R., Ip, E. H., Marsh, A. P., & Rejeski, W. J. (2018). Change in health-related quality of life and social cognitive outcomes in obese, older adults in a randomized controlled weight loss trial: Does physical activity behavior matter? Journal of Behavioral Medicine, 41(3), 299–308. 10.1007/s10865-017-9903-6 Fanning, J., Brooks, A., Ip, E., Nicklas, B., Rejeski, W., Nesbit, B., & Ford, S. (2020). A Mobile Health Behavior Intervention to Reduce Pain and improve Health in Older Adults with Obesity and Chronic Pain: The MORPH pilot trial. Frontiers in Digital Health, 2(598456). 10.3389/fdgth.2020.598456 Fanning, J., Brooks, A. K., Hsieh, K. L., Kershner, K., Furlipa, J., Nicklas, B. J., & Rejeski, W. J. (2021). The Effects of a Pain Management-Focused Mobile Health Behavior Intervention on Older Adults’ Self-efficacy, Satisfaction with Functioning, and Quality of Life: a Randomized Pilot Trial. International Journal of Behavioral Medicine, (3), 1–7. 10.1007/s12529-021-10003-3 Fanning, J., Rejeski, W. J., Leng, I., Barnett, C., Lovato, J. F., Lyles, M. F., & Nicklas, B. J. (2022). Intervening on exercise and daylong movement for weight loss maintenance in older adults: A randomized, clinical trial. Obesity, 30(1), 85–95. 10.1002/OBY.23318 Georgoulis M Yiannakouris N Kechribari I Lamprou K Perraki E Vagiakis E Kontogianni MD Dose-response relationship between weight loss and improvements in obstructive sleep apnea severity after a diet/lifestyle interventions: secondary analyses of the “MIMOSA” randomized clinical trial Journal of clinical sleep medicine 2022 18 5 1251 1261 10.5664/jcsm.9834 34915980 Gill LE Bartels SJ Batsis JA Weight management in older adults Current Obesity Reports 2015 4 3 379 388 10.1007/s13679-015-0161-z 26627496 Houston, D. K., Ding, J., Nicklas, B. J., Harris, T. B., Lee, J. S., Nevitt, M. C., et al. (2009). Overweight and obesity over the adult life course and incident mobility limitation in older adults: The health, aging and body composition study.American Journal of Epidemiology Houston, D. K., Nicklas, B. J., & Zizza, C. A. (2009). Weighty concerns: the growing prevalence of obesity among older adults.Journal of the American Dietetic Association Katula JA Rejeski WJ Wickley KL Berry MJ Perceived difficulty, importance, and satisfaction with physical function in COPD patients Health and Quality of Life Outcomes 2004 2 18 10.1186/1477-7525-2-18 15056389 Katz PP Neugebauer A Does satisfaction with abilities mediate the relationship between the impact of rheumatoid arthritis on valued activities and depressive symptoms? Arthritis & Rheumatology 2001 45 3 263 269 10.1002/1529-0131(200106)45:3<263::AID-ART259>3.0.CO;2-W Martin, C. K., Das, S. K., Lindblad, L., Racette, S. B., McCrory, M. A., Weiss, E. P., et al. (2011). Effect of calorie restriction on the free-living physical activity levels of nonobese humans: Results of three randomized trials. Journal of Applied Physiology McAuley E Blissmer B Self-efficacy determinants and consequences of physical activity Exercise and Sport Sciences Reviews 2000 28 2 85 88 10902091 McAuley E Konopack JF Motl RW Morris KS Doerksen SE Rosengren KR Physical activity and quality of life in older adults: influence of health status and self-efficacy Annals of Behavioral Medicine 2006 31 1 99 103 10.1207/s15324796abm3101_14 16472044 McAuley E Lox C Duncan TE Long-term maintenance of exercise, self-efficacy, and physiological change in older adults Journal of Gerontology 1993 48 4 218 224 10.1093/geronj/48.4.P218 McAuley E Mailey EL Mullen SP Szabo AN Wójcicki TR White SM Growth trajectories of exercise self-efficacy in older adults: influence of measures and initial status Health Psychology 2011 30 1 75 83 10.1037/a0021567 21038962 McAuley E Szabo A Gothe N Olson EA Self-efficacy: implications for physical activity, function, and functional limitations in older adults American Journal of Lifestyle Medicine 2011 5 4 361 369 10.1177/1559827610392704 McEwan D Rhodes RE Beauchamp MR What happens when the party is over?: sustaining physical activity behaviors after intervention cessation Behavioral Medicine 2022 48 1 1 9 10.1080/08964289.2020.1750335 32275199 Melanson EL Keadle SK Donnelly JE Braun B King NA Resistance to exercise-induced weight loss: Compensatory behavioral adaptations Medicine and Science in Sports and Exercise 2013 45 8 1600 1609 10.1249/MSS.0b013e31828ba942 23470300 Nicklas BJ Gaukstern JE Beavers KM Newman JC Leng X Rejeski WJ Self-monitoring of spontaneous physical activity and sedentary behavior to prevent weight regain in older adults Obesity (Silver Spring, Md.) 2014 22 6 1406 1412 10.1002/oby.20732 24585701 Physical Activity Guidelines Advisory Committee (2018). 2018 physical activity guidelines advisory committee report. Washington, DC: US Department of Health and Human Services Piercy KL Troiano RP Ballard RM Carlson SA Fulton JE Galuska DA The physical activity guidelines for Americans Journal of the American Medical Association 2018 320 19 2020 2028 10.1001/jama.2018.14854 30418471 Ray KM Hector LL Lynes LK Stewart AL Painter PL Dibble SL Assessment of satisfaction with physical fitness in kidney transplant recipients 38 Medicine & Science in Sports & Exercise 1996 28 5 7 10.1097/00005768-199605001-00038 8775345 Reboussin BA Rejeski WJ Martin KA Callahan K Dunn AL King AC Sallis JF Correlates of satisfaction with body function and body appearance in middle- and older aged adults: The activity counseling trial (ACT) Psychology & Health 2000 15 2 239 254 10.1080/08870440008400304 Redman LM Heilbronn LK Martin CK de Jonge L Williamson DA Delany JP Ravussin E Metabolic and behavioral compensations in response to caloric restriction: Implications for the maintenance of weight loss Plos One 2009 4 2 e4377 10.1371/journal.pone.0004377 19198647 Rejeski WJ Brent S Miller M Dunn AL King AC Sallis JF Mediators of increased physical activity and change in subjective well-being: Results from the activity counseling trial (ACT) Journal of Health Psychology 2001 6 2 159 168 10.1177/135910530100600206 22049319 Rejeski WJ Marsh AP Chmelo E Rejeski JJ Obesity, intentional weight loss and physical disability in older adults Obesity Reviews 2010 11 9 671 685 10.1111/j.1467-789X.2009.00679.x 19922431 Rejeski WJ Spring B Domanchuk K Tao H Tian L Zhao L McDermott MM A group-mediated, home-based physical activity intervention for patients with peripheral artery disease: effects on social and psychological function Journal of Translational Medicine 2014 12 29 10.1186/1479-5876-12-29 24467875 Sallis JF Cervero RB Ascher W Henderson K Kraft MK Kerr J An ecological approach to creating active living communities Annual Review of Public Health 2006 27 297 322 10.1146/annurev.publhealth.27.021405.102100 16533119 Thompson D Peacock OJ Betts JA Substitution and compensation erode the energy deficit from exercise interventions Medicine and Science in Sports and Exercise 2014 46 2 423 10.1249/MSS.0000000000000164 24435073 Wang X Lu J Gao Y Song J Li Y Hundei W Dose-response association between long-term weight loss in young adults and later-life metabolic health Obesity (Silver Spring, Md.) 2022 30 6 1289 1297 10.1002/oby.23436 35534791 Winston-Salem, North Carolina (2021). US census bureau: https://www.census.gov/quickfacts/winstonsalemcitynorthcarolina
PMC009xxxxxx/PMC9579672.txt	==== Front Child Youth Care Forum Child Youth Care Forum Child & Youth Care Forum 1053-1890 1573-3319 Springer US New York 36275014 9717 10.1007/s10566-022-09717-6 Original Paper Effects of an Online Play-Based Parenting Program on Child Development and the Quality of Caregiver-Child Interaction: A Randomized Controlled Trial http://orcid.org/0000-0002-6012-0245 Solís-Cordero Katherine [email protected] 1 Marinho Patricia 2 Camargo Patricia 2 Takey Silvia 2 Lerner Rogério 3 Ponczek Vladimir Pinheiro 4 Filgueiras Alberto 5 Landeira-Fernandez Jesus 6 Fujimori Elizabeth 1 1 grid.11899.38 0000 0004 1937 0722 School of Nursing, University of São Paulo, Avenida Doutor Ernéas de Carvalho Aguiar, São Paulo, 419, 05403-000 Brazil 2 Tempo Junto, São Paulo, Brazil 3 grid.11899.38 0000 0004 1937 0722 Institute of Psychology, University of São Paulo, São Paulo, Brazil 4 grid.452413.5 0000 0001 0720 8347 São Paulo School of Economics-FGV, São Paulo, Brazil 5 grid.412211.5 0000 0004 4687 5267 State University of Rio de Janeiro, Rio de Janeiro, Brazil 6 grid.4839.6 0000 0001 2323 852X Department of Psychology, Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Brazil 18 10 2022 2023 52 4 935953 28 9 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Background Studies assessing the effects of parenting programs have focused on interventions delivered through face-to-face modalities. There is a need for research to evaluate the effects of online parenting programs on child development, such as the BEM Program (‘Play Teaches Change’ in English), an online play-based parenting program that teaches caregivers on how to introduce playful interactions into their daily household chores. Objective To assess the effects of the BEM Program on child development and the quality of caregiver-child interaction. Method A two-arm randomized controlled trial was conducted in a socioeconomically disadvantaged district of São Paulo city in Brazil. 129 children aged 12–23 months and their caregiver were randomly assigned to receive either the BEM Program for 8 weeks (intervention, n = 66) or standard child care (control, n = 63). Data were collected at baseline and endline of the intervention through home visits and online interviews. An intention-to-treat analysis was conducted. Results The intervention showed positive effects on child development, by improving language development (Cohen’s d = 0.20, 95%CI 0.08–0.47) and reduced intrusiveness (Cohen’s d = 0.35, 95%CI 0.06–0.65) of caregiver-child interaction. No significant differences were observed in caregiver’s repertoire and engagement in age-appropriate play activities with the child while doing the household chores, parenting sense of competence and perceived stress. Conclusions Despite the small size and low adherence to the program, such promising results advance evidences for fully remote parenting programs and their effects on child development. Keywords Child development Internet-based intervention Parenting Parent–child interactions Randomized controlled trial núcleo ciência pela primeira infânciaissue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction Globally, a significant number of children under the age of 5 years in low-middle income countries (LMICs) live in conditions that hinder their fundamental right to healthy development (Lu et al., 2016). This reality represents a major public health concern and improving these children’s lives is currently a global priority. Poverty is a critical factor which determines the quality of the environment and the presence of other negative conditions that put children at risk of not achieving their developmental potential (Grantham-McGregor et al., 2007). Early experiences in life shape the quality of brain architecture which is crucial for child’s development and lifelong physical and mental health, school performance and income (Fox et al., 2010; Heckman, 2006). Research demonstrates that a stimulating and nurturing home environment in early childhood might protect children from the negative effects of poverty and toxic stress on early child development (Bick & Nelson, 2017; Shonkoff, 2012; Shonkoff & Phillips, 2000). Caregivers living under poor conditions may experience greater financial and emotional difficulties in fulfilling their parenting role (Britto et al., 2017; Harris et al., 2020). Thus, these caregivers often require support to create stimulating and nurturing environments to promote child development (Britto & Ulkuer, 2012; Rayce et al., 2017). Parenting programs are interventions or services that aim to improve parenting interactions, behaviors, practices, knowledge, attitudes and beliefs regarding child care to promote better child health and development (Britto et al., 2017). These programs are the most suitable strategy to reach both caregivers and children in order to enhance child development and health through early learning and responsive interactions (Jeong et al., 2021). Consequently, researchers and policy makers have increased their interest in investing in parenting interventions to promote early child development. Meta-analyses and systematic reviews have confirmed the effectiveness of parenting programs on improving caregiver-child interaction and child development (Britto et al., 2017; Jeong et al., 2018; Rayce et al., 2017). Specifically, previous studies revealed a positive effect of short duration (approximately 8–12 weeks) parenting programs on child development outcomes (Kochanska et al., 2013; McGillion et al., 2017; Murray et al., 2016; Pontoppidan et al., 2016; Vally et al., 2015). Nonetheless, studies on the effectiveness of parenting programs focusing on caregiver-child interaction and child development have mainly been delivered through face-to-face modalities such as home visits, parent group meetings or interventions during well-child visits. Hence, most of the available evidence on parenting programs is based on these delivery modalities, and evidence-based online parenting programs are scarce in LMIC (Jeong et al., 2021), where the majority of children are at risk of not meeting their cognitive and socioemotional potential (McCoy et al., 2016). Online Parenting Programs Parenting programs are a promising strategy to guide and motivate caregivers and promote the acquisition of parenting skills that enhance the healthy development of the children and prevent future problems (Pontoppidan et al., 2016, WHO, 1997). While various types of interventions, including nutrition and health, can support healthy development, evidence has revealed that those parenting programs that include components to directly improve caregiver-child interaction are more effective in improving early child development outcomes (Engle et al., 2007). Traditional delivery modalities of parenting programs that require a face-to-face meeting either at home or at the health center present challenges in reaching a large number of families due to the logistical, economical and human requirements (Breitenstein et al., 2014; Shah et al., 2016). Reaching socioeconomically disadvantaged populations in Brazil could represent another challenge. Parents, and specially mothers, face important time constraints for participating in face-to-face interventions due to their work, household chores, child care and the territorial extension of the country. Therefore, remote interventions such as online interventions represent an innovative option that reduces the challenges of face-to-face activities and reaches a greater number of children and their families. Previous systematic reviews and meta-analyses revealed that online parenting interventions targeting children in the age range of 0–5 years were effective to improve caregivers and child outcomes (Breitenstein et al., 2014; Harris et al., 2020; Nieuwboer et al., 2013). Nonetheless, a recent systematic review showed a limited number of studies that assess the effect of remotely delivery parenting programs on caregiver-child interaction and child development (Solís-Cordero et al., 2022). Thus, it is imperative to develop and test remotely delivered interventions that focus on children living under adverse conditions to ensure positive child outcomes. The BEM Program (an acronym for Brincar Ensina a Mudar in Portuguese, which in English is Play Teaches Change) is an online play-based parenting program that teaches female caregivers, living in socioeconomically disadvantaged areas of São Paulo city and responsible for the care of children from 12 to 23 months of age, how to introduce playful interactions into their daily household chores to enhance the quality of caregiver-child interaction and child development. Play as a Strategy to Improve the Quality of Caregiver-Child Interaction and Child Development Previous studies have shown that encouraging play between caregiver and child provided an ideal opportunity to strengthen caregiver-child interactions and improve child development (Abimpaye et al., 2019; Attanasio et al., 2014; Shah et al., 2019; Yousafzai et al., 2016). However, caregivers are often not aware of the need for play materials, playmates, and responsive interaction (Aboud et al., 2013). Children living under poverty and disadvantaged socioeconomic backgrounds are more likely to experience less playful and stimulating interactions with their caregivers (Grantham-McGregor et al., 2007). In Brazil, specifically, a study titled: “Playing in Brazilian Slums” revealed that: 50% of caregivers had difficulty finding time to play with children, 68% had difficulty taking care of the house and children at the same time, 88% of mothers turn to screens to distract their children and take care of household chores. For 63% of children, the main place to play is indoors, only 29% of mothers have a playground in the community (Unidos pelo brincar, 2021). Moreover, a study entitled: “Perceptions and Practices of Society in Relation to Early Childhood” showed that only 19% of the participants recognized play as one of the important aspects for the development of children under 3 years of age (Fundação Maria Cecilia Souto Vidigal, 2013). Caregivers can take advantage of different times of the day to incorporate playful activities that promote caregiver-child interactions and child development. Playful moments are everywhere, and even daily chores alongside parents can be turned into playful opportunities (Galinsky, 2010; Yogman et al, 2018). The novelty of the BEM Program comes from this idea of taking advantage of everyday simple moments and household items to play with children to improve the quality of caregiver-child interaction and child development. Therefore, in addition to being online, another core element that makes the BEM Program stand out as an innovative intervention is the incorporation of playful activities between the caregiver and their children in the daily routine. Many other parenting programs might require caregivers to allocate exclusive time to play with their children. The BEM Program represents a valuable option for female caregivers, who find it difficult to separate time to play with their children or who do not know how to take advantage of the little time they have available with their children. Since this program teaches caregivers about the importance of engaging in playful activities with their children, what kind of activities they can incorporate into their daily routine and how to incorporate these activities with their children into their daily household chores. Current Study The aim of this study was to assess the effect of the BEM Program on child development (primary outcome), quality of caregiver-child interaction, caregiver’s repertoire and engagement in age-appropriate play activities with the child while doing household chores, parenting sense of competence and perceived stress (secondary outcomes). We further examined whether adherence to the program, caregiver’s education level and number of children at home moderated the effect of the intervention on primary and secondary outcomes. We hypothesized that, compared to the control group, children from families who received the BEM Program would have fewer developmental delays and caregivers would engage more in age-appropriate play activities with the child during the daily routine. We also hypothesized that caregiver-child dyads who received the BEM Program would have higher quality caregiver-child interactions and sense of parental competence and would experience less stress than dyads from the control group. Finally, we hypothesized that the effect of the intervention would be larger among caregivers who participated more in the program, had a higher educational level, and had fewer number of children at home. Methods Study Design and Setting We performed a two-arm randomized controlled trial to assess the effects of the BEM Program on child development and the quality of caregiver-child interaction, and other secondary outcomes. The intervention group received the BEM Program and the control group received the standard care. Dyads participating in the study who received standard care did not receive any type of intervention other than the care received in the daycare. We adhered to the Consolidated Standards of Reporting Trials (CONSORT) guidelines for reporting our study. This randomized controlled trial was conducted between July 2019 and August 2020 in Campo Limpo, a socioeconomically disadvantaged district of São Paulo city in Brazil. This district is located 20 km from the city center, and has one of the highest prevalence of households in slums (highly populated urban residential area where living conditions are poor) (26.6%) (Rede Nossa São Paulo, 2019). Participants and Sample Size The study recruited 129 children aged 11–21 months and their female caregivers. Female caregiver was defined as the female adult who lived with the child, who had the responsibility of caring, stimulating, loving and educating the child, and with whom the child has formed the strongest emotional bonds in the first year of life (Fundação Maria Cecilia Souto Vidagal, 2017). Therefore, the female caregiver was not necessarily the child’s mother; rather, sometimes it was the grandmother. The sample size was calculated based on the global development indicator (Denver II) (Frankenburg, 1992). Considering a power of 80%, alpha of 5%, R2 of covariates (Denver at baseline, sex, age, race) of 56% (based on Phase I results), the sample size was 160 families per group. Inclusion criteria were children aged between 11 and 21 months at enrollment, who lived in Campo Limpo, who attended daycare centers where the BEM Program was implemented, and had a female caregiver who had a smartphone with Internet access. Children with clinical conditions that interfered with the typical course of development, twins and caregivers who did not understand Portuguese were excluded. In order to achieve the required sample size, the study was conducted in two cohorts. Recruitment took place at two timepoints, in July 2019 and January 2020. Caregiver-child dyads were recruited at 14 daycare centers located in the district where the study was conducted, and that accepted to participate in the research. All female caregivers of children aged between 11 and 21 months at the time of recruitment were invited to participate during a face-to-face meeting at each daycare center. Recruitment materials were also sent home with the children and delivered to parents via mobile messaging. Once the caregiver showed interest in participating in the research, data was collected to confirm the inclusion criteria, and her consent was obtained for participation in the study. Intervention The BEM Program is an eight-week online play-based parenting program which aims to improve caregiver-child interaction for enhancing the development of children aged 12 to 23 months from socially disadvantaged families. The BEM Program is an innovative parenting program which consists of 8 video classes and 40 text and audio messages sent through WhatsApp, which teaches female caregivers how to play with their children during the daily routine, using resources available at home. The theoretical framework in which we based our intervention is the Nurturing Care for Early Childhood Development Framework of the World Health Organization. This framework presents five core components of nurturing care for children reaching their developmental potential: good health, adequate nutrition, opportunities for early learning, security and safety and responsive caregiving (WHO, 2018). The Nurturing Care encourages the creation and implementation of interventions that provide opportunities for early learning and support responsive caregiving, two components of nurturing care that can be supported by caregiver-child playful interactions. In terms of opportunities for early learning, evidence shows that young children under 3 years old learn and explore the world through playing (Ginsburg et al., 2007; Kochanska et al, 2013; Yogman et al., 2018) Playful interactions between caregiver and children during everyday activities, such as cooking, cleaning, feeding, bathing and sleeping, with the use of materials and household objects that are commonly available at home represent great opportunities for early learning (Popp & Thomsen, 2017; Yogman et al., 2018). Regarding the component of responsive caregiving, caregivers are children’s first playmates and the home environment is where the children’s first experiences with play occur (Brazelton & Greenspan, 2002) The framework recognizes the importance of responsive interactions to stimulate brain connections and enhance caregiver-child interactions. Through playing, caregivers observe and learn to respond to children’s movements, sounds, gestures and verbal requests which contributes to build an emotional bond and secure attachment (WHO, 2018). Thus, the creation and implementation of the BEM Program encourages opportunities for early learning and supporting responsive caregiving through playful interactions during daily activities with the use of materials and household objects commonly available at home. The content of the BEM Program is adapted to the children's age group (12–23 months), focused on four prominent and frequent household chores of the caregiver’s daily routine: (1) while she cooks or washes the dishes, (2) while she washes clothes, (3) while she cleans the house, and (4) while she takes care of the child. Each of the videos presented a playful activity that could be included into a specific moment of the caregiver’s routine. In addition to explaining how to do the activity, the video included information such as safety tips and benefits for caregiver-child interaction and child development. Text and audio messages complement the content of the video lessons by providing additional information on child development, responsive parenting, strengthening the bond with children and taking advantage of moments of interaction to promote early learning experiences. Video, text and audio messages were selected from previous studies of proof of concept and feasibility. The BEM Program was delivered on two separate occasions. The first cohort received the program between October and November 2019; and the second between April and May 2020, during COVID-19 pandemic. Outcomes Primary outcome: Child development was assessed using the Ages and Stages-3, Brazilian version, a caregiver completed scale that assesses child development through five domains: communication, gross motor coordination, fine motor coordination, problem-solving and personal-social skills (Filgueiras et al., 2013). For each domain, the child can get a score between 0 and 60. The higher the score, the better the child development. Secondary outcomes: Quality of caregiver-child interaction was assessed through the Coding Interactive Behavior (CIB), a tool for coding parent-infant interactions using a set of observable behaviors (Feldman, 1998). The CIB consists of 43 scales; 22 are adult scales, 16 are child scales, and 5 are dyadic scales. A 5-min video of an interaction between the caregiver and the child while playing was coded on a 5-point scale, where 1 implies a minimal level of the specific behavior or attitude and 5 implies a maximal level (Feldman, 1998). Coding was conducted by trained coders, blind to any other information. To analyze the quality of interaction, eight composites were created by grouping different scales, according to the indications of the CIB instrument. Repertoire and engagement in age-appropriate play activities with the child while doing the household chores was assessed. Due to the non-existence of an instrument that would allow to asses play with the child while doing household chores, a questionnaire was created and pre-tested by the researchers. Through yes/no questions we verified whether the caregiver played with the child while doing household chores (at the four specific moments addressed in the intervention: while she cooks or washes the dishes, while she washes clothes, while she cleans the house, and while she takes care of the child) and if it was considered possible to incorporate playing while doing the household chores. In addition, from a list of options of household chores and playful activities, the participants could choose which playful activities they engaged in while doing each of the household chores in their routine. Then, we calculated a score of the total number of activities according to each of the household chores. Finally, engagement in age-appropriate play activities with the child while doing the household chores was evaluated by analyzing one 5-min video, using another instrument created by the research team for this purpose. The instrument consisted of a checklist that identifies whether the caregiver engaged with the child in playful activities while doing household chores (at the four specific moments addressed in the intervention). Two trained examiners assessed the videos. Prior to coding, examiners were trained and reliability was established at r > 0.8 for both examiners. More details of both instruments are reported elsewhere. Parenting sense of competence was evaluated through the Parenting Sense of Competence Scale (PSOC), which consists of 17-item scale answered on a 6-points scale ranging from “strongly disagree” to “strongly agree”. The PSOC measures parents’ satisfaction with parenting and their self-efficacy in the parenting role. A higher score indicates a greater sense of parenting competence. Studies have reported an internal consistency of the PSOC Scales Scores of 0.80. (Ohan et al., 2000). We used the Portuguese translation authorized by the authors (Linhares & Gaspardo, 2017). Perceived stress was measured using the Perceived Stress Scale, a 14-item instrument designed to determine the degree to which life situations are considered as stressful during the last month. A higher level of stress is indicated by higher scores on this scale (Cohen et al., 1983). The internal consistency of the Brazilian version was 0.82. (Luft et al., 2007). Measurements Child’s sex, age, prematurity and skin color, caregiver’s age, education, work, marital status and skin color; and family’s income, number of children and beneficiary of Bolsa Familia (Brazilian cash-transfer Program) were collected using a sociodemographic questionnaire. Caregiver’s adherence to the program was calculated by the number of videos watched and class time watched per caregiver (%per caregiver), data that were obtained through the Wistia Platform database (online video platform that registered the access to the videos and watched time). Using this data, we classified adherence into (1) adhered caregivers who watched 4 or more video classes, and (2) non-adhered caregivers who watched fewer than 4 classes. Data Collection Data were collected at baseline and endline of the intervention by 10 trained data collectors. Both baseline and endline data collection for cohort 1, and baseline data collection for cohort 2 was performed during home visits. Due to the COVID-19 pandemic and the stay-at-home measures it was no longer feasible to do the home visits for endline data collection of cohort 2. Data collection procedure modifications due to the COVID-pandemic have been published elsewhere (Solís-Cordero et al., 2021). Briefly, visits were adapted to an online video-conference to collect the endline data for cohort 2 only. The participants were interviewed by the data collectors through a video-conference using WhatsApp or Zoom. Data collectors used the REDCap platform (Research Electronic Data Capture) directly on tablets. This software allows the collection of data offline and the direct transmission of responses to a database, which avoids wasting time and minimizes typing errors (RedCap, 2018). Tablets were also used for recording the two 5-min videos used to assess two of our outcomes (caregiver-child interaction and repertoire and engagement in age-appropriate play activities with the child). Randomization and Blinding Eligible caregiver-child dyads were randomized to the intervention or control group after the collection of baseline data. Randomization was at the family level; families were stratified based on child daycare center and Denver scores at baseline (global, language, adaptative and gross motor); within each stratum, half of the families were randomly selected to the intervention and half to the control group. Random assignment was done by a researcher who had no role in the direct implementation of the intervention. Due to the characteristics of the intervention, blinding of participants was not possible. However, the examiners who assessed the trial outcomes were blinded to group allocation. Statistical Analyses Descriptive statistics were computed for the entire study sample by randomized group. Numerical data were described with location (mean) and dispersion (standard deviation) measures, whereas categorical variables were described as absolute and relative frequencies. Group comparisons of transversal variables were carried out with Student or Welch t-test and Wilcoxon-Mann–Whitney test for continuous variables and chi-squared test for categorical ones. A longitudinal comparison of intervention groups was done using linear mixed models (LMM) or its generalized version (GLMM) on all available data; the distribution used for the latter is noted in the table. The model incorporated time (baseline and endline), randomized group (control vs intervention) and group by time interaction. Intervention effects were estimated for this model as the difference between the intervention and control arms in mean change from baseline to endline. Model 1 was the intent-to treat. Model 2 adjusted for characteristics which were not comparable across intervention and control groups at baseline. All models were adjusted for stratification variables used in randomization. The residual normality assumption was assessed by inspecting the corresponding QQ plot and homoscedasticity with Levene test. All analyses were conducted in R 4.2.1. Subgroup analyses were conducted to examine whether intervention effects differed by (1) adherence to the program (categorized as caregiver having watched ≥ or < 4 intervention videos), (2) caregiver educational level and (3) number of children at home. Cohen’s d effect sizes were calculated. Ethics The study received approval from the Fundação José Luiz Egydio Setubal Institutional Review Board (IRB File # 09,941,319.1.0000.5567). All caregivers provided written informed consent (or thumbprint) at the time of the baseline data collection. The corresponding author takes responsibility for the integrity of the data and the accuracy of the data analysis. Results Sociodemographic variables and adherence to the intervention were similar for the two cohorts and therefore, participants for both cohorts were combined in a pooled analysis. Of the 496 caregiver–child dyads assessed for eligibility, 129 were enrolled in the study for the baseline data collection, and 66 were allocated to the intervention group and 63 to the control group (Fig. 1).Fig. 1 CONSORT diagram for the randomized controlled trial Loss to follow-up was 31%. Families lost to follow up were more likely to receive Bolsa Familia (32.5%, p = 0.013) and had more children (2.1 children on average, p = 0.047). Table 1 shows the characteristics of the study population at baseline. Only caregiver’s race was significantly different between intervention and control group at baseline (p = 0.019).Table 1 Baseline characteristics of caregiver-child dyads between randomized groups Randomized group Control (n = 63) Intervention (n = 66) N % N % Child characteristics Sex Male 34 54.0 37 56.1 Age mean (SD), months 16.3 (3.6) 16.1 (3.2) Prematurity No 52 82.5 53 80.3 Race White 29 46.0 26 39.4 Caregiver characteristics Age mean (SD), years 29.8 (9.1) 31.4 (6.8) Education mean (SD), years 11.9 (3.2) 12.2 (3.3) Marital status With partner 44 69.8 50 75.8 Work Employed 37 58.7 46 69.7 Race* White 12 19.0 25 37.9 Family characteristics Monthly income (Reais) < 1000 17 27.0 15 22.7 1000–3000 35 55.6 36 54.6 > 3000 11 17.5 15 22.7 Bolsa família* Yes 10 15.9 14 21.2 Number of children mean (SD) 1.8 (0.9) 1.8 (0.9) p < 0.05; Brazilian currency: 1USD = R$5.8 in March 2021; ** Brazilian cash transfer program The BEM Program significantly improved the communication domain of child development compared to the control group (p < 0.001) (Table 2), Cohen’s d effect size was 0.20 (95%CI 0.08–0.47). No significant differences were observed in the other developmental domains (Fig. 2), although descriptively they have tended to be better in the endline of the intervention group compared to the control group.Table 2 BEM Program effects on child development (primary outcome) Control (n = 63) Intervention (n = 66) Model 1a p Model 2b p Baseline Endline Baseline Endline Communication 42.4 40.5 40.1 44.2 < 0.001+ < 0.001+ Gross motor 49.4 51.1 48.7 53.0 0.136+ 0.140+ Fine motor 42.9 46.7 46.3 49.7 0.907 + 0.949+ Problem solving 43.4 42.5 44.4 42.6 0.856 0.864 Socio-emotional 46.6 43.3 46.7 45.4 0.402 + 0.384+ Data are mean of a range of 0–60 aModel 1: Intent-to treat analysis. bModel 2: Adjusted for caregiver’s race, which was not comparable between randomized groups at baseline. +GLMM (Poisson distribution) Fig. 2 BEM Program Effect on Child Development (Primary Outcome) Quality of caregiver-child interaction outcomes are reported in Table 3. We found positive effects of the BEM Program on the component intrusiveness of the quality of caregiver-child interaction (p = 0.015), Cohen’s d effect size was 0.35 (95%CI 0.06–0.65).Table 3 BEM Program effects on quality of caregiver-child interaction outcomes Components of the quality of caregiver-child interaction Control (n = 63) Intervention (n = 66) Model 1p Model 2 bp Baseline Endline Baseline Endline Sensitivity 3.6 3.7 3.5 3.7 0.437 0.433 Intrusiveness 1.8 1.8 1.8 1.6 0.015 0.016 Limit setting 4.3 4.3 4.2 4.3 0.892 0.886 Involvement 3.3 3.5 3.3 3.6 0.403 0.394 Withdrawal 1.4 1.3 1.2 1.2 0.593 0.606 Compliance 3.5 3.8 3.4 3.9 0.351 0.360 Reciprocity 3.6 3.6 3.5 3.8 0.207 0.203 Negative states 1.5 1.4 1.6 1.5 0.600+ 0.678+ Data are mean of a range of 0–5. aModel 1: Intent-to treat analysis. bModel 2: Adjusted for caregiver’s race, which was not comparable between randomized groups at baseline. +GLMM (gamma distribution) Finally, there was no effect of the BEM Program on the repertoire and engagement in age-appropriate play activities with the child while doing the household chores (Table 4). Parenting sense of competence and perceived stress, both outcomes assessed at the caregiver level, were not affected by the intervention.Table 4 BEM Program effects on the repertoire and engagement of caregiver in play activities Control (n = 63) Intervention (n = 66) Model 1 p Model 2b p Baseline Endline Baseline Endline Repertoire of play activities while cooking or washing the dishes (range 0–9), mean 2.6 3.5 3.0 3.4 0.385+ 0.401+ Repertoire of play activities while washing clothes (range 0–9), mean 1.9 2.6 2.4 3.7 0.310+ 0.318+ Repertoire of play activities while cleaning the house (range 0–11), mean 3.7 5.3 4.0 5.5 0.764+ 0.815+ Repertoire of play activities while taking care of the child (range 0–14), mean 7.1 8.5 7.4 8.3 0.574 0.643 Caregiver’s engagement in play activities while doing household chores (% of caregivers) 26.3 32.6 27.9 40.0 0.686* 0.689* aModel 1: Intent-to treat analysis. bModel 2: Adjusted for caregiver’s race, which was not comparable between randomized groups at baseline. +GLMM (Poisson distribution), *GLMM (binomial) We found no differences in any of the outcomes when adjusting for caregiver’s race (Model 2). Moreover, we found no moderating effect of the caregiver’s education level, number of children at home and adherence of caregivers to the program on any primary and secondary outcomes. Discussion We conducted this study to examine the effects of an online play-based parenting program on child development (primary outcome), quality of caregiver-child interaction, caregiver’s repertoire and engagement in age-appropriate play activities with the child while doing the household chores, parenting sense of competence and perceived stress (secondary outcomes). Our findings show that the BEM Program had significant positive effects on the communication domain of child development, but not on other developmental domains, including cognitive, motor, socio-emotional development, and problem solving. Moreover, the program improved the quality of caregiver-child interaction, in terms of intrusiveness. Previous parenting programs that promoted caregiver-child interactions and child development through responsive play found similar effects on early language development. A systematic review including 21 studies which assessed stimulation interventions based on responsive play with children aged 24 months and younger, demonstrated a medium effect size (0.47) on language (Aboud & Yousafzai, 2015). Additionally, a study carried out in Brazil with low-income families which provided an intervention promoting interaction through reading to 566 parent–child dyads with children aged 2–4 years, showed significant impact of the intervention on child language (Weisleder et al., 2018). The positive effect of the BEM Program on the communication domain of child development might be explained by the fact that the content of the messages and videos constantly reinforced the importance of activities that stimulate the child's speech. Further, evidence has shown that adult–child play benefits widely children’s language development (Moreno, 2016). Benefits on the components of the quality of caregiver-child interaction were also seen in previous responsive parenting interventions. In relation to intrusiveness, a randomized controlled trial conducted in South Africa with 449 pregnant women with adverse socioeconomic circumstances showed that the mothers, who received an intervention which encourages sensitive and responsive interactions with her child, were significantly less intrusive while interacting with their child at 6 months of age (Cooper et al., 2009). Furthermore, at-risk mothers in the United States who participated in a high-intensity comprehensive parenting intervention were less intrusive with their child at 16 months of age (Guttentag et al., 2014). The prior studies have used face-to-face interventions; the most common modalities of delivery being home visits, group sessions, and clinic appointments. The BEM Program undertook a novel online delivery method, sending caregivers weekly videos and daily messages to promote responsive interactions which could be built into their regular household chores and activities. This study was the first step towards creating a scalable and effective remotely delivered program. Remotely delivered programs have important advantages for the service provider and participants. In regard to the service provider, staff implementing the intervention do not need to travel to participants’ home, reducing costs of ineffective visits, and allowing the intervention to be delivered to a large number of families in a short amount of time (Sawyer et al., 2017). Remote program delivery also enables the continuity of the intervention even in situations for which face-to-face contact is challenging such as in large geographical areas and when movement is restricted such as during the COVID-19 pandemic. Considering these last two advantages remotely delivered programs such as the BEM Program might be easier to scale. For participants, remotely delivered interventions ensures access to information when it is convenient for the participant, without being restricted by scheduled home visits or appointments (Sawyer et al., 2017). Despite these advantages of the remotely delivered parenting programs, our results revealed low adherence to the program. It is well-known that adherence is a frequent challenge faced by intervention programs with consequences on its effectiveness (Souza et al., 2006). In the case of our intervention, the low adherence rates might be due to the lack of relationship-building that often occurs with home visits or group sessions, which likely increases adherence (Burrell et al., 2018; Girvin et al., 2007). Furthermore, a systematic review revealed no evidence of improvements from interventions that did not include direct contact between participants and providers. In contrast, those interventions incorporating direct contact were significantly effective (Harris et al., 2020). To overcome the challenge represented by the low adherence rates the BEM Program could, in the future, be integrated within an existing face-to-face intervention. This type of mixed-modality intervention is supported by a systematic review that demonstrated that programs using more than one modality had a greater impact on child development than those using only one modality (Britto et al., 2015). The short duration and the low intensity of the BEM Program could have contributed to the lack of effects on cognitive, motor, socio-emotional development, and problem solving, as well as on the caregiver outcomes. Evidence shows that the shorter and less intense the intervention, the more likely it is to have a smaller effect (Engle et al., 2007). Studies suggested that the minimum duration of a parenting program should be 12 months if the goal is to observe positive results in cognitive and socioemotional development, as well as parental outcomes (Britto et al., 2015). Sociodemographic characteristics were associated with the caregiver’s adherence to the program and retainment in the study. Higher level of caregiver education was associated with better adherence to the program, a finding that is consistent with previous research (Eisner & Meidert, 2011; Souza et al., 2006). Further, families who remained in the study were less likely to benefit from Bolsa Família, i.e., they had better social conditions. Similar findings were reported in a systematic review where families with the greatest needs and who would benefit most from the intervention dropped out (Barrett, 2010). Caregivers with fewer financial needs and higher level of education might be more likely to recognize the impact of early interventions on child development such as the BEM Program which motivates them to participate more in the program. Moreover, families who remained in the study were more likely to have only one child. Pontoppidan et al. (2016) demonstrated that families with greater number of children dropped out. This situation can be understood considering that the caregivers with more children at home might be busier with less time available to participate in the program or they might believe that they have more experience to take better care of the child than women who take care of fewer children. Strengths of our study design and implementation included the use of self-report and observational assessments to measure child development and caregiver’s engagement in age-appropriate play activities with the child while doing the household chores, and the successful adaptation of data collection to a 100% online interview. The study also had several limitations including small sample size and a high loss to follow-up. Finally, we cannot ignore the limitations due to the barriers imposed by technology to keep the participants engaged in the intervention, such as lack of devices and access to Internet, and that participants must have some level of digital literacy. Future research to assess the effect of BEM Program should incorporate strategies to improve participants’ adherence to the program, such as a tutor to support the implementation of the program, or while integrating the BEM Program into an existing face-to-face early childhood service, such as the Family Health Strategy, which is largely disseminated in Brazil. In addition, further research should consider not only the videos as adherence, but the impact of the messages as well. Conclusion An online play-based parenting program promoting caregiver-child interaction and child development showed positive results on language development and the quality of caregiver-child interaction among socioeconomically disadvantaged families. Despite the small size and low adherence to the program, such promising results advance evidences for fully remote parenting programs and their effects on improving child development. Further evaluation is needed to test strategies to improve participants’ adherence to the program and demonstrate the effectiveness of program on a larger scale. Acknowledgements The authors would like to thank the children and caregivers who generously participated in this study. Taís Coppini Pereira e Lucas Ferreria for all the administrative and logistical work to carry out the study. The examiners who participated in the data collection and analysis of the videos. Dr. Leila Larson for her valuable contributions to the manuscript. Funding This study was financed by Núcleo Ciência pela Primeira Infãncia. Declarations Conflict of interest We have no conflicts of interest to disclose. Ethical Approval The study received approval from the Fundação José Luiz Egydio Setubal de São Paulo Human Ethics Committee (CAAE: 09941319.1.0000.5567). The trial was registered with The Brazilian Clinical Trials Registry, number RBR-10c27qjq, “retrospectively registered”. Consent to Participate All caregivers provided written informed consent (or thumbprint) at the time of the baseline data collection. The trial was registered with The Brazilian Clinical Trials Registry, number RBR-10c27qjq, “retrospectively registered”. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Abimpaye M Dusabe C Nzabonimpa J Ashford R Pisani L Improving parenting practices and development for young children in Rwanda: Results from a randomized control trial International Journal of Behavioral Development 2019 10.1177/0165025419861173 Aboud FE Singla DR Nahil MI Borisova I Effectiveness of a parenting program in Bangladesh to address early childhood health, growth and development Social Science and Medicine 2013 97 250 258 10.1016/j.socscimed.2013.06.020 23871435 Aboud FE Yousafzai AK Global health and development in early childhood Annual Review of Psychology 2015 66 433 457 10.1146/annurev-psych-010814-015128 25196276 Attanasio OP Bentham J Fernández C Grantham-McGregor S Douglas CM Rubio-Codina M Using the infrastructure of a conditional cash transfer program to deliver a scalable integrated early child development program in Colombia: Cluster randomized controlled trial BMJ (Online) 2014 10.1136/bmj.g5785 25266222 Barrett H The delivery of parent skills training programmes Meta-analytic studies and systematic reviews of what works best 2010 Family and Parenting Institute Bick J Nelson C Early experience and brain development Wiley interdisciplinary reviews Cognitive Science 2017 8 1–2 e1387 10.1002/wcs.1387 Brazelton, T. B., & Greenspan, S. I. (2002). As necessidades essenciais das crianças: O que toda criança precisa para crescer, aprender e se desenvolver. Trad. Cristina Monteiro. Porto Alegre: Artmed. Breitenstein SM Gross D Christophersen R Digital delivery methods of parenting training interventions: A systematic review Worldviews on Evidence-Based Nursing 2014 11 3 168 176 10.1111/wvn.12040 24842341 Britto, P. R., Lye, S. J., Proulx, K., Yousafzai, A. K., Matthews, S. G., Vaivada, T., Perez-Escamilla, R., Rao, N.,… Early Childhood Development Interventions Review Group, for the Lancet Early Childhood Development Series Steering Committee. (2017). Nurturing care: promoting early childhood development. Lancet, 389(10064), 91-102. doi: 10.1016/S0140-6736(16)31390-3 Britto, P. R., Ponguta, L. A., Reyes, C., & Karnati, R. (2015). A Systematic Review of Parenting Programmes for Young Children. Retrieved from https://www.unicef.org/earlychildhood/files/P_Shanker_final__Systematic_Review_of_Parenting_ECD_Dec_15_copy.pdf Britto PR Ulkuer N Child development in developing countries: Child rights and policy implications Child Development 2012 83 1 92 103 10.1111/j.1467-8624.2011.01672.x 22277009 Burrell L Crowne S Ojo K Snead R O’Neill K Cluxton-Keller F Duggan A Mother and home visitor emotional well-being and alignment on goals for home visiting as factors for program engagement Maternal and Child Health Journal 2018 22 1 43 51 10.1007/s10995-018-2535-9 29855836 Cohen, S., Kamarck, T., & Mermelstein, R. (1983). A global measure of perceived stress. Journal of Health and Social Behavior, 24(4), 385–396. Retrieved from https://pdfs.semanticscholar.org/bed9/2e978f5bca851a79b16d8499b8ca21eeb3d6.pdf Cooper PJ Tomlinson M Swartz L Landman M Molteno C Stein A Mc Pherson K Murray L Improving quality of mother-infant relationship and infant attachment in socioeconomically deprived community in South Africa: Randomised controlled trial BMJ (clinical Research Ed.) 2009 338 b974 10.1136/bmj.b974 19366752 de Souza N Sardessai V Joshi K Joshi V Hughes M The determinants of compliance with an early intervention programme for high-risk babies in India Child Care and Health Development 2006 32 1 63 72 10.1111/j.1365-2214.2006.00576.x Eisner M Meidert U Stages of parental engagement in a universal parent training program Jornal Primary Prevention 2011 32 83 93 10.1007/s10935-011-0238-8 Engle PL Black MM Behrman JR de Mello M Gertler PJ Kapiriri L Martorell R Young ME Strategies to avoid the loss of developmental potential in more than 200 million children in the developing world Lancet 2007 369 9557 229 242 10.1016/S0140-6736(07)60112-3 17240290 Feldman R Coding interactive behavior (CIB) 1998 Bar-Ilan University Filgueiras A Pires P Maissonette S Landeira-Fernandez J Psychometric properties of the Brazilian-adapted version of the ages and stages questionnaire in public child daycare centers Early Human Development 2013 89 561 576 10.1016/j.earlhumdev.2013.02.005 23507472 Fox SE Levitt P Nelson CA How the timing and quality of early experiences influence the development of brain architecture Child Development 2010 81 1 28 40 10.1111/j.1467-8624.2009.01380.x 20331653 Frankenburg WK Dodds J Archer P Shapiro H Bresmck B The Denver II: A major revision and restandardization of the denver developmental screening test Pediatrics 1992 89 1 91 97 10.1542/peds.89.1.91 1370185 Fundação Maria Cecilia Souto Vidagal. (2017). Primeiríssima infância creche: necessidades e interesses de famílias e crianças. Fundação Maria Cecilia Souto Vidigal. Fundação Maria Cecilia Souto Vidagal. (2013). Primeiríssima Infância da gestação aos três anos Percepções e práticas da sociedade brasileira sobre a fase inicial da vida. Fundação Maria Cecilia Souto Vidigal. Galinsky, E. (2010). Mind in the making. The seven essential life skills every child needs. Harperstudio. Ginsburg KR The importance of play in promoting healthy child development and maintaining strong parent-child bond Pediatrics 2007 119 1 182 191 10.1542/peds.2011-2953 17200287 Girvin H DePanfilis D Daining C Predicting program completion among families enrolled in a child neglect preventive intervention Research on Social Work Practice 2007 17 6 674 685 10.1177/1049731507300285 Grantham-McGregor S Cheung YB Cueto S Glewwe P Richter L Strupp B Developmental potential in the first 5 years for children in developing countries The Lancet 2007 369 60 70 10.1016/S0140-6736(07)60032-4 Guttentag CL Landry SH Williams JM Baggett KM Noria CW Borkowski JG Swank PR Farris JR Crawford A Lanzi RG Carta JJ Warren SF Ramey SL "My Baby & Me": Effects of an early, comprehensive parenting intervention on at-risk mothers and their children Developmental Psychology 2014 50 5 1482 1496 10.1037/a0035682 24447116 Harris M Andrews K Gonzalez A Prime H Atkinson L Technology-assisted parenting interventions for families experiencing social disadvantage: A meta-analysis Prevention Science: The Official Journal of the Society for Prevention Research 2020 21 5 714 727 10.1007/s11121-020-01128-0 32415543 Heckman JJ Skill formation and the economics of investing in disadvantaged children Science 2006 312 1900 1902 10.1126/science.1130121 16809525 Jeong J Franchett EE Ramos de Oliveira CV Rehmani K Yousafzai AK Parenting interventions to promote early child development in the first three years of life: A global systematic review and meta-analysis PLoS Medicine 2021 18 5 e1003602 10.1371/journal.pmed.1003602 33970913 Jeong J Pitchik HO Yousafzai AK Stimulation interventions and parenting in low- and Middleincome countries: A meta-analysis Pediatrics 2018 141 4 e20173510 10.1542/peds.2017-3510 29500293 Kochanska G Kim S Boldt LJ Nordling JK Promoting toddlers' positive social-emotional outcomes in low-income families: A play-based experimental study Journal of Clinical Child and Adolescent Psychology 2013 42 5 700 712 10.1080/15374416.2013.782815 23557253 Linhares, M.B.M., & Gaspardo, C.M. (2017). Tradução da versão do instrumento adaptada pelo FOI, autorizada pelo autor. Versão original: Gibaud-Wallston, J., & Wandersman, L. P. (1978). Development and utility of the Parenting Sense of Competence Scale. Paper presented at the anual meeting of the American Psychological Association, Toronto. Lu C Black MM Richter LM Risk of poor development in young children in low-income and middle-income countries: An estimation and analysis at the global, regional, and country level The Lancet Global Health 2016 4 12 e916 e922 10.1016/S2214-109X(16)30266-2 27717632 Luft CDB Sanches SO Mazo GZ Andrade A Versão brasileira da Escala de Estresse Percebido: Tradução e validação para idosos Revista De Saúde Pública 2007 41 4 606 615 10.1590/S0034-89102007000400015 17589759 McCoy DC Peet ED Ezzati M Danaei G Black MM Sudfeld CR Fawzi W Fink G Early childhood developmental status in low- and middle-income countries: National, regional, and global prevalence estimates using predictive modeling PLoS Medicine 2016 13 6 e1002034 10.1371/journal.pmed.1002034 27270467 McGillion M Pine JM Herbert JS Matthews D A randomised controlled trial to test the effect of promoting caregiver contingent talk on language development in infants from diverse socioeconomic status backgrounds Journal of Child Psychology and Psychiatry 2017 58 10 1122 1131 10.1111/jcpp.12725 28429816 Moreno MA Supporting child play JAMA Pediatrics 2016 170 2 184 10.1001/jamapediatrics.2015.2505 26830871 Murray L De Pascalis L Tomlinson M Vally Z Dadomo H MacLachlan B Woodward C Cooper PJ Randomized controlled trial of a book-sharing intervention in a deprived South African community: Effects on carer-infant interactions, and their relation to infant cognitive and socioemotional outcome Journal of Child Psychology and Psychiatry 2016 57 12 1370 1379 10.1111/jcpp.12605 27465028 Nieuwboer CC Fukkink RG Hermanns JMA Online programs as tools to improve parenting: A meta-analytic review Child and Youth Services Review 2013 35 1823 1829 10.1016/j.childyouth.2013.08.008 Ohan JL Leung DW Johnston C The parenting sense of competence scale: Evidence of a stable factor structure and validy Canadian Journal of Behavioural Science 2000 32 4 251 261 10.1037/h0087122 Pontoppidan M Klest SK Sandoy TM The incredible years parents and babies program: a pilot randomized controlled trial PLoS One 2016 11 12 e0167592 10.1371/journal.pone.0167592 27974857 Popp, J. M., & Thomsen, B. S. (2017). A commentary on the importance of father–child play and children’s development. Infant Mental Health Journal, 38(6), 785–788. Retrieved from https://onlinelibrary.wiley.com/doi/abs/10.1002/imhj.21681 Rayce SB Rasmussen IS Klest SK Patras J Pontoppidan M Effects of parenting interventions for at-risk parents with infants: a systematic review and meta-analyses BMJ OPEN 2017 7 12 10.1136/bmjopen-2016-015707 REDCap. (2018). REDCap. https://redcap.hc.fm.usp.br/ Rede Nossa São Paulo. (2019). Mapa da desigualdade 2019. Retrieved from https://www.nossasaopaulo.org.br/wp-content/uploads/2019/11/Mapa_Desigualdade_2019_tabelas.pdf Sawyer MG Reece CE Bowering K Jeffs D Sawyer ACP Mittinty M Lynch JW Nurse-moderated internet-based support for new mothers: Non-inferiority, randomized controlled trial Journal of Medicine Internet Research 2017 19 7 1 14 10.2196/jmir.6839 Shah R Isaia A Schwartz A Atkins M Encouraging parenting behaviors that promote early childhood development among caregivers from low-income urban communities: A randomized static group comparison trial of a primary care-based parenting program Maternal and Child Health Journal 2019 23 1 39 46 10.1007/s10995-018-2589-8 30003519 Shah R Kennedy S Clark MD Bauer SC Schwartz A Primary care-based interventions to promote positive parenting behaviors: A meta-analysis Pediatrics 2016 137 5 e20153393 10.1542/peds.2015-3393 27244800 Shonkoff JP Leveraging the biology of adversity to address the roots of disparities in health and development Proceedings of the National Academy of Sciences of the United States of America 2012 109 Suppl. 2 17302 17307 10.1073/pnas.1121259109 23045654 Shonkoff, Jack P, & Phillips, D. A. (2000). From Neurons to Neighborhoods: The Science of Early Childhood Development. Retrieved from http://www.nap.edu. Solís-Cordero K Duarte LS Fujimori E Effectiveness of remotely delivered parenting programs on caregiver-child interaction and child development: A systematic review Journal of Child and Family Studies 2022 10.1007/s10826-022-02328-8 35615461 Solís-Cordero K Lerner R Marinho P Camargo P Takey S Fujimori E Overcoming methodological challenges due to COVID-19 pandemic in a non-pharmacological caregiver-child randomly controlled trial International Journal of Social Research Methodology 2021 10.1080/13645579.2021.1933067 Unidos pelo brincar. (2021). O brincar nas favelas brasileiras. Retrieved from: http://aliancapelainfancia.org.br/wp-content/uploads/2021/05/Pesquisa-Brincar-nas-Favelas-Brasileiras-deck-Webinar-Direito-do-Brincar.pptx-2.pdf Vally Z Murray L Tomlinson M Cooper PJ The impact of dialogic book-sharing training on infant language and attention: A randomized controlled trial in a deprived South African community Journal of Child Psychology and Psychiatry 2015 56 8 865 873 10.1111/jcpp.12352 25399699 Weisleder A Mazzuchelli DSR Lopez AS Neto WD Cates CB Goncalves HA Fonseca RP Oliveira J Mendelsohn AL Reading aloud and child development: A cluster-randomized trial in Brazil Pediatrics 2018 141 1 10.1542/peds.2017-0723 World Health Organization. (2018). Nurturing care for early childhood development: a framework for helping children survive and thrive to transform health and human potential. Switzerland; 2018. Retrieved from: https://apps.who.int/iris/bitstream/handle/10665/272603/9789241514064-eng.pdf?ua=1 World Health Organization. (1997). Improving Mother/child Interaction To Promote Better Psychosocial Development in Children. 1997. Retrieved from https://www.who.int/mental_health/media/en/29.pdf Yogman M Garner A Hutchinson J Hirsh-Pasek K Golinkoff RM The power of play: A pediatric role in enhancing development in young children Pediatrics 2018 142 3 e20182058 10.1542/peds.2018-2058 30126932 Yousafzai AK Obradovic J Rasheed MA Rizvi A Portilla XA Tirado-Strayer N Siyal S Memon U Effects of responsive stimulation and nutrition interventions on children’s development and growth at age 4 years in a disadvantaged population in Pakistan: A longitudinal follow-up of a cluster-randomised factorial effectiveness trial The Lancet. Global Health 2016 4 8 e548 e558 10.1016/S2214-109X(16)30100-0 27342433
PMC009xxxxxx/PMC9579823.txt	==== Front sppfe PFE Policy Futures in Education 1478-2103 SAGE Publications Sage UK: London, England 10.1177_14782103221134188 10.1177/14782103221134188 Special Issue: Higher Education Policy and Management in the Post-Pandemic Review of higher education policy during the pandemic: A Spanish perspective https://orcid.org/0000-0002-1977-7026 Mula-Falcón Javier https://orcid.org/0000-0002-2019-6245 Cruz-González Cristina https://orcid.org/0000-0002-8319-5127 Domingo Segovia Jesús https://orcid.org/0000-0003-4451-337X Lucena Rodríguez Carmen Facultad de Ciencias de la Educación, 16741 Universidad de Granada , Granada, Spain Javier Mula-Falcón, Facultad de Ciencias de la Educación, Universidad de Granada, Campus de Cartuja, Granada 18071, Spain. Email: [email protected] 5 2022 18 10 2022 18 10 2022 21 4 465485 © The Author(s) 2022 2022 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. The COVID-19 pandemic has prompted profound changes in Higher Education. Thus, policymakers in different national contexts worldwide needed to design alternative responses to deal with new educational scenarios. In Spain, rethinking educational management in Higher Education remains an issue of current debate. Methodological readjustments towards virtual teaching, the digital divide due to socio-economic and cultural issues of the students, unequal access to education, or a decrease in internationalization have been some of the most significant adversities faced during this time. Amid this crisis, the measures taken by political leaders and university managers played an essential role. This study aims to provide an overview of the policy measures developed during this period, describing some of the most important decisions taken by different universities in Spain. To this end, an exploration based on secondary data from extensive literature reviews is carried out to construct a descriptive analysis of the measures implemented in Spanish universities. The findings highlight the coordinated action of the Spanish university system and the staunch defense of face-to-face teaching. This health crisis has also highlighted the deficits of this level of education and shed light on its future. Spain faces major challenges in the field of higher education. Consequently, the Spanish university system must begin building the foundations for educational innovation and training education professionals without fear of online scenarios. Finally, this article also proposes suggestions to guide policymakers in dealing with future adverse situations. COVID-19 higher education emergency situation online teaching challenges opportunities Ministry of Science and Innovation PID2019-105631GA-I00/10.13039/501100011033 Ministry of Universities (Spain) FPU19/00942 Junta de Andalucía (Fondos FEDER) B_SEJ-534-UGR20 typesetterts10 ==== Body pmcIntroduction In December 2019, a new pandemic caused by SARS-COV 2 (commonly known as coronavirus) hit the entire planet, causing numerous devastating effects in areas such as health, economy, and education (Babbar and Gupta, 2021; Geldsetzer, 2020; Pather et al., 2020; Toquero, 2021). In education, in a matter of months, the COVID-19 outbreak affected more than 1.6 billion students in more than 190 countries across all continents (WHO, 2020). According to UNESCO, more than 23.4 million students in higher education were affected (UNESCO, 2020). As the pandemic evolved globally, governments implemented a series of measures designed to contain the spread of the virus. Universities and colleges were among the first to close. In the first phase of the pandemic’s impact, mandatory confinement and the impossibility of maintaining university activities face-to-face had an enormous impact on higher education institutions. As a result, several countries had to develop a contingency plan for this unexpected phenomenon. In this case, the primary objective was to implement a new educational system that would be better adapted to an unexpected pandemic situation without a vaccine, in which the continued application of preventive security measures to control the virus was necessary (Bonilla-Guachamín, 2020). Thus, one of the general lines of action at the European level was the suspension of all face-to-face classes, leading to three major modes of action: the deployment of distance learning modalities, using various formats and platforms (with or without the use of technology); the support and mobilization of educational staff and communities; and attention to the health and well-being of students (Mishra et al., 2020; Zhou et al., 2020). The shift from face-to-face to distance learning did not come without challenges and obstacles, particularly access to technological infrastructure and the absence of competencies and pedagogies for distance education. At the same time, it was suggested that the forced move to distance teaching and learning offered significant opportunities to propose more flexible learning models, explore blended or hybrid learning, and blend synchronous learning with asynchronous learning (Area-Moreira et al., 2021). In this sense, one of the great challenges faced by teachers at all educational levels was the alternation of different teaching scenarios (online, hybrid, or face-to-face). This alternation was motivated by the continuous adaptations that had to be carried out in educational centers, depending on the evolution of the pandemic (Toledo, 2020). The scientific literature also highlights another significant challenge when developing inclusive educational practices in times of pandemics. In this case, assessment was a concern, and it is necessary to highlight that teachers at all educational levels had to incorporate new assessment tools—beyond the use of ICTs or software—that were inclusive and took into account the diversity of students. In most cases, and without specific training for this purpose, the pandemic forced them to reconstruct their educational approaches, formative and summative assessment tools, and lesson plans to enter distance education platforms (Karalis, 2020). If we explore the history of higher education, this is not the first time this educational level has faced challenges of this type. Since the creation of universities, other pandemics such as the Black Death have affected university dynamics in different geographical locations. However, universities have had to find ways to adapt and continue their commitment to science and education (Thomas and Foster, 2020). Returning to the current scenario, the suspension of all face-to-face activities in higher education was an almost unanimous decision worldwide (El Masri and Sabzalieva, 2020; Joaquín et al., 2020; Karakose, 2021). This decision was motivated by the very nature of the pandemic and to safeguard public health in the affected countries (Sahu, 2020). As a measure to contain the pandemic, school closures led to the accelerated deployment of distance learning solutions to ensure pedagogical continuity in higher education (Darras et al., 2021; Engzell et al., 2021). Face-to-face played a fundamental role in developing active pedagogies, particularly affect-based pedagogy. Personal contact is crucial to converting the elements of knowledge to be transmitted into a reality that interpellates and mobilizes each of the students and the group (Grossi et al., 2018). This affective bonding goes hand in hand with the development of contextualized knowledge, and both elements are crucial for motivation. Confinement once again confronted us with the recurring issue of work-life balance, which affects both students and teachers. However, facing the teaching challenges associated with the virtual format mentioned previously has been a personal responsibility of the teacher rather than a matter of educational policies. Moreover, it is not at all different from the placing the responsibilities for training in the hands of teachers before the pandemic, which depended entirely on the initiative of each teacher. In a scenario of such educational complexity, an institutional response to these teaching challenges is necessary (Moye, 2021). Although the pandemic had a considerable impact at all educational levels, higher education was particularly affected by highlighting its existing adversities that already painted a worrying picture. These problems include increasing losses of public funding, inequalities of access to this educational level, and the questionable connection between curriculum and the current demands of society (Brewer et al., 2019). Given that higher education as an essential source of talent and creativity in our world, it is necessary to analyze its current shortcomings and the challenges it must face to achieve a more sustainable and inclusive future (Means, 2013). The global debate on how higher education institutions should act and cope with the effects of the pandemic has yielded different educational policy responses from one institution to another across the terrestrial sphere. In this case, our focus is on the Spanish context. It is important to note that higher education in Spain has been no exception when it comes to the adversities faced by the emergence of COVID-19. Ensuring the safety of the university community, the quality of teaching, and equal opportunities, are just some of the imminent challenges facing higher education institutions in Spain. Organizations such as CRUEs (Conference of Rectors of Spanish Universities) have promoted a Spanish University system with strong notions of social justice in which no student is left without the right to quality education. In addition, working with health institutions and establishing joint initiatives with other public and private entities was key to decision-making on educational policy issues (Blankenberger and Williams, 2020; El Masri and Sabzalieva, 2020). However, despite the good intentions and efforts of the Spanish university system, the pandemic has created a complex and changing scenario, which has forced us to act in a very short time, and possibly, certain responses need to be reviewed and (re) considered (Boer, 2021; Camilleri, 2021; DeMatthews et al., 2020). It is important to note that despite the regulations in force in the Spanish territory, each Spanish university has the autonomy to establish a contingency plan according to its criteria and contextual situation despite the different guidelines proposed by the government. This is why, during this pandemic period, Spanish universities have taken different decisions based on their principle of autonomy. It should be noted that almost all universities have sought to guarantee maximum presence in their classrooms, prioritizing equal access and continuation of university studies for students. However, in some periods, this presence in the classroom has been affected, and restrictive measures recommended by the health authorities have had to be considered. This study briefly discusses how higher education has dealt with the challenge of the pandemic, focusing on the Spanish context. Our aim is to provide an overview of the political measures developed during this period and show some of the most important decisions taken by different universities in the Spanish context. In short, the objective is to analyze which measures have been implemented by some Spanish universities to deal with the health crisis generated by COVID-19. Throughout this review, we explore the various regulations, instructions, and guidelines issued by the Spanish higher education administrations during the pandemic. Furthermore, we present Spain as the object of study because we intend to describe a specific case within the European scenario. Finally, and taking these initiatives as a reference, we establish a series of political-educational implications that may be of interest for future similar situations. Spanish contexts From the Decree 463/2020, of March 14, declaring a state of alarm for managing the health crisis caused by COVID-19, the Spanish government declared that all educational processes would continue through distance and online modalities, whenever and wherever possible. This measure covered compulsory and basic education (primary and secondary education) and any educational modality included in the Spanish educational system (early childhood education, baccalaureate, university education, vocational training, artistic, and sports education). Faced with this situation, all the country’s educational centers were forced to close their doors, adapting their educational processes to a completely online scenario. With the exception of some universities in Spain with a long tradition in distance and online education, most of them were barely prepared for the development of this type of teaching (Crawford et al., 2020). In this context, and to ensure the greatest possible coordination between the different universities, the Ministry of Universities, in collaboration with the Ministry of Health, prepared a document containing a series of recommendations and health measures to coordinate and guide universities in this new scenario resulting from the pandemic. This document was called “Prevention, hygiene, and health promotion measures against COVID-19 for university centers in the academic year 2020-2021.” However, the administrative and management freedom that characterizes Spanish universities (Organic Law 4/2007, April 12, 2007, amending Organic Law 6/2001, of December 21, 2001, on universities) has made it easier for these recommendations to be adapted to the characteristics of each context. Nevertheless, all universities have ensured compliance with the following fundamental principles (CRUE, 2020):- Maintain educational quality standards, - ensure equity and educational flexibility, - maintain as much face-to-face activity as possible, - ensure adherence to the planned academic calendar. Methodology Design and data analysis Documentary content analysis was carried out to achieve the objectives described in the previous section. According to Bardin (1992), this makes it possible to describe, compare, and explain—systematically and objectively—the content of any type of communicative text. In the case of the present research, there were two sources under study. First, the document entitled “COVID-19 prevention, hygiene and health promotion measures for university centers in the 2020–2021 academic year” prepared by the Ministry of Universities in collaboration with the Ministry of Health; and second, the resolutions approved by the different Spanish public universities for developing contingency plans in the emergency health situation resulting from COVID-19. All the analyzed documentation was published between March and December 2020. Thus, 20 documents were analyzed and issued, one at the national level by the Ministry of Universities and 19 by different universities throughout the country. The 19 universities were selected randomly from among the 50 Spanish public universities. Generally speaking, one university was chosen per community, except in the case of autonomous communities with many universities, such as Andalusia and Madrid, where two universities were selected (Table 1).Table 1. Documents selected for analysis. University/Institution Publication date Document title 1. Ministry of Universities May 11, 2020 COVID-19 prevention, hygiene, and health promotion measures for university centers in the 2020–2021 academic year. 2. Complutense University of Madrid July 21, 2020 A strategic teaching framework for the academic year 2020/2021 3. University of Alcalá September 10, 2020 Plan of action for the Alacalá University to adapt the university activity in the academic year 2020–2021. 4. University of Barcelona July 31, 2020 Contingency plan for the University of Barcelona in the face of the COVID-19 health crisis. 5. University of Cantabria July 24, 2020 Procedure for returning to the on-site activity after the confinement decreed by the state of health alert due to COVID-19. 6. University of Castilla-La Mancha August 31, 2020 UCLM Academic Contingency Plan for the development of the academic year 2020/21 7. University of Extremadura June 15, 2020 Course 20–21 attendance procedure adapted to the “new normal” COVID-19 requirements. 8. University of Granada June 25, 2020 Plan to adapt education in the 2020–2021 academic year to the health measures derived from the COVID-19 pandemic. 9. University of Islas Baleares September 7, 2020 Action plan of the University of the Balearic Islands for the 2020-21 academic year in response to the COVID-19 pandemic. 10. University of La Laguna July 1, 2020 General criteria for teaching and evaluation under adapted attendance conditions during the 2020–2021 academic year. 11. University of La Rioja December 21, 2020 Contingency plan for the 2020–2021 academic year to adapt the teaching activity to the requirements of the health situation. 12. University of Murcia October 21, 2020 Recommended contingency plan with a semi-presence scenario to reduce risk and preserve the essential academic and research activities. 13. University of Navarra July 31, 2020 Contingency plan for the Public University of Navarra (2020–21 academic year) 14. University of Oviedo July 17, 2020 Teaching activity adaptation plan for the 2020–2021 academic year 15. University of País Vasco May 31, 2020 Guidelines for teaching and learning planning for the 2020–2021 academic year. 16. University of Salamanca August 31, 2020 Model for the adaptation of teaching at USAL for the 2020–2021academic year 17. University of Santiago de Compostela June 20, 2020 Guidelines for the development of safe teaching for the 2020–2021 academic year 18. University of Seville June 19, 2020 Academic criteria for the adaptation of the official degrees of the University of Seville to the health requirements resulting from COVID-19 during the 2020–2021 academic year. 19. University of Valencia July 15, 2020 Adaptation of the teaching of the official degrees of the University of Valencia for the 2020–2021 academic year. 20. University of Zaragoza July 6, 2020 Agreement of July 6, 2020, of the Governing Council of the University of Zaragoza, whereby guidelines are adopted to address the development of teaching in the 2020–2021 academic year in the new normal situation. Source: Author’s own. The choice of the universities analyzed was another significant decision that had to be addressed in this study. Therefore, selection criteria were established to offer a representative view of the different actions implemented in Spain. First, we considered it important to select at least one university per autonomous community. Second, we limited our study to public universities, excluding private universities. In addition, it was also decisive that these universities had made their contingency plans for the COVID-19 pandemic public. Finally, it is important to point out that the documents analyzed were dated between May and September 2020 since this was when the Spanish government granted autonomy to the different universities to adapt their educational services according to the unique circumstances of the autonomous communities. Moreover, another of the selection criteria was membership of the Shanghai Ranking, which is an academic ranking of the most prestigious universities in the world. We selected one university for each autonomous community (except for Madrid, Andalusia, and Barcelona, which, due to their large number of universities, it was decided to choose two). This selection was based on the Shanghai ranking position, choosing only those universities that were at the top of the ranking in their autonomous community. Once the documents were selected, a thematic content analysis (Braun and Clarke, 2006) was conducted using the NVivo 12 qualitative software. A mixed method was applied for this analysis, using a combination of deductive (conceptual/theoretical) and inductive (emergent) thematic analysis. The researchers previously defined the deductive categories after reading and analyzing the state document (COVID-19 prevention, hygiene, and health promotion measures for university centers in the 2020–2021 academic year). The inductive categories emerged from the data themselves after reading and analyzing the various contingency plans. Thus, the analysis started from four major deductive categories (Central categories or codes) that branched into others due to the emerging categories (Subcategories/subcodes). The following table shows the categories finally used in the study, along with their definition (Table 2).Table 2. Categories and subcategories used for the analysis. Deductive categories/codes (central categories or codes) Definition Inductive categories/codes (subcategories/subcodes) Definition Contingency Plan This category collects information on the general characteristics of contingency plans. General This includes those plans that do not provide freedom of adaptation. Per discipline This includes those plans that give freedom of adaptation to the different faculties or centers. Teaching Scenarios This category collects information on the possible scenarios that universities describe in their contingency plans. Totally virtual This includes everything related to the virtual scenario. Face-To-Face Collects information about the face-to-face scenario. Hybrid Gathers information on the hybrid or bimodal scenario. Online teaching requirements This category includes all those aspects related to the requirements described by the universities for the development of online teaching. Digital skills training (Teachers, pupils, Administrative and service employees) Collects information related to digital skills training. Digital Divide Collects information on actions related to alleviating the digital divide. Availability of resources and spaces (Virtual system improvement, classroom improvement). Collects information on adaptations of resources and spaces. Evaluation This category gathers all the information related to the teaching evaluation processes of the various contingency plans. Face-To-Face tests Collects information related to face-to-face evaluations Telematically conducted final tests Collects information related to virtual evaluations Other types of evaluation Collects information related to other types of evaluations Source: Author’s own. The studies were entered into the qualitative software NVIVO 12 and were coded after a critical reading of the content. Different researchers supervised this process to give greater coherence to the research process. The consultation and analysis of official documents published by the university institutions included in this study provided us with a high level of reliability due to their very nature. In addition, the search, selection, and analysis processes were carried out at all times using processes agreed upon by all the researchers involved in this research. This gave the research a greater degree of reliability and accuracy, as each aspect of the search and analysis process was agreed upon after individual reflection and discussion. In addition, to achieve quality standards, the researchers monitored the entire process to minimize potential biases by checking the credibility of the coding in the analysis program (Miles and Huberman, 1994). Results This section will present the results of the analysis of the main measures implemented by the selected universities. For the purposes of clarity, the results have been grouped according to the four deductive categories of the analysis. Figure 1 shows a hierarchical map of the categories (deductive) and subcategories (inductive) of the thematic analysis.Figure 1. Hierarchical map of the categories (deductive) and subcategories. Source: Authors’ own through Nvivo 12. The contingency plan The Ministry of Universities decreed the development of a contingency plan to gather information regarding the various adaptations made to university teaching. In this sense, the ministry recommended that these plans should gather information on areas such as teacher training, the adaptation of evaluation systems, and the development of digitalization strategies. Despite all the recommendations proposed by the ministry, each university prepared this document, adapting the plan as much as possible to its particular circumstances. It is therefore unsurprising that this document differs slightly between universities. In this regard, the main difference observed is that, although the ministry proposed the preparation of a contingency plan for each institution and study plan, not all the universities followed this distinction, as seen, the example, in the University of Navarra and Cantabria (n = 2). Figure 2 shows a group query of the cross-referencing of the subcategories of the “Contingency Plan” code with the contingency plans of the different universities. This figure indicates which universities included the distinction between each faculty and study plan.Figure 2. Contingency plan code group query. Source: Authors’ own through Nvivo 12. Online, hybrid, and face-to-face teaching The ministry’s main recommendation was to adapt teaching to a fully online format. This strategy aimed to ensure the quality of the teaching offered while safeguarding the health of the students and staff of the different university institutions.Figure 3. Training plans group query. Source: Authors’ own through Nvivo 12. Despite this recommendation, the ministry itself stressed in the document the need to maintain as much face-to-face teaching as possible: “we reiterate the desirable preponderance of face-to-face teaching as the most appropriate form of quality higher education in general terms” (p.3). To meet this objective and to respond to the health needs generated by the pandemic, the ministry included the possibility of making online teaching activities compatible with face-to-face activities, thus allowing the development of a mixed or hybrid model. Along these lines, most Spanish universities included three different scenarios in their action plans, depending on the different healthcare requirements of the country. These possible scenarios were totally virtual teaching, hybrid or mixed teaching, and only face-to-face teaching. However, not all universities implemented all three scenarios. The following table (Table 3) shows the various scenarios considered by each university.Table 3. Teaching scenarios considered by each institution. University/Institution Face-to-face scenario Online scenario Mixed or hybrid model University of Alcalá X a X X University of Barcelona X University of Cantabria X University of Castilla-La Mancha X X X University Complutense of Madrid X a X X University of Extremadura X X University of Granada X University of Islas Baleares X X University of La Laguna X X X University of La Rioja X X X University of Murcia X X X University of Navarra X X X University of Oviedo X a X University of País Vasco X University of Salamanca X X University of Santiago de Compostela X X X University of Seville X University of Valencia X University of Zaragoza X Total 13 12 14 aReference is made to a pre-pandemic classroom scenario (without adaptations). Source: Authors’ own. The various universities defined the face-to-face scenario as “safe adapted face-to-face teaching,” that is, a scenario of a return to face-to-face teaching but adapted to the new normality generated by COVID-19. That is, a face-to-face mode that complies with the health and hygiene standards dictated by the Ministry of Health and is based on social distancing. To this end, the universities described a series of adaptations and adjustments to their teaching spaces and furnishings to comply with these new health safety standards. Among the most popular measures were the restructuring and reduction of classroom capacity following the recommended social distancing (1.5 m), the adoption of precautions such as the mandatory use of masks or the dispensing of hydroalcoholic gels, the regulation of entrances and exits to avoid conglomerations, and attendance control systems for tracking COVID positives. Although most of the universities analyzed contemplated this scenario in their contingency plans, some either did not contemplate it, such as the universities of Zaragoza, Valencia, Seville, Salamanca, Basque Country, and Granada (n = 6); or they contemplated full attendance without considering the adaptations of the health authorities. This group includes the universities of Madrid, Oviedo, and Alcalá (n = 3), which, despite including this alternative, mention the almost null possibility of being able to develop such a scenario: “Scenario 0 (unlikely). 100% face-to-face teaching with no safety distance. This is the pre-pandemic situation” (the University of Madrid, p.2). Concerning the possible online scenario, almost the majority of the institutions analyzed (n = 13) included this as a last alternative in the event of an extreme worsening of the health situation or possible new confinements of the population. In general terms, this scenario eliminated presential attendance in all teaching activities and replaced them with synchronous teaching sessions. To this end, the contingency plans of the different universities mention the need to use digital videoconferencing tools and different strategies to deal with the practical content in this completely online situation, such as (1) adapting the content; (2) reducing the size of the practical groups when the content requires face-to-face attendance; and (3) creating heterogeneous working groups according to the availability of technical resources to ensure educational equity. The hybrid scenario is defined as the development of both online and face-to-face teaching depending on the size of the class groups and classrooms where the methodology is applied. Within this scenario, the analysis of contingency plans reveals a wide variety of possible alternatives. Thus, some universities (n = 7) defend the development of theoretical teaching virtually (synchronously) and practical face-to-face teaching (Balearic Islands, Granada, Oviedo, Salamanca, Alcalá, La Laguna, and Valencia University), while others propose practices based on the division of class groups into subgroups that rotated their presence in the classroom regardless of whether the content is practical or theoretical. This practice is most frequently mentioned in the documents on the hybrid modality (n = 7). However, within this modality, there are differences between universities. In terms of the latter, four universities mention live broadcasting of the class, with half of the students being at home (University of Castilla-La-Mancha; Extremadura, Seville, and Santiago). In addition to this alternative, three universities mention the possibility of live broadcasting with half of the class from other adapted classrooms that they call “mirror classrooms.” This group includes the universities of the Basque Country, Navarra, and La Rioja. According to these universities, this measure was adopted to ensure that all students could attend the virtual sessions regardless of their personal or family resources. Finally, within the hybrid scenario, four universities also mention the possibility of repeating the classroom lessons or using digital tools to give continuity to the lessons, that is, asynchronous teaching. However, the universities that propose this alternative (Seville, Granada, Balearic Islands, and La Laguna) argue that this strategy is a complementary or substitute element when face-to-face teaching or live broadcasting is not possible due to a lack of personal or technological resources. Regardless of all these possibilities, the documents analyzed mention two key aspects: (1) the maintenance of the maximum possible percentage of face-to-face activities—only the University of Alcalá mentions a minimum percentage of 30%—and (2) ensuring educational equity that is, that all students receive the same amount of online and face-to-face teaching time. Despite the scenarios proposed, all the universities emphasized their eminently face-to-face nature—following the ministry guidelines—proposing that the options of virtual and blended teaching are exceptional situations in the face of the pandemic. Thus, for example, the University of Seville mentions in its preamble that “The University of Seville thus reaffirms its eminently face-to-face nature in the conviction that the relationships established within the university provide an important value in the exercise of the functions of creation and transmission of knowledge. Furthermore, its face-to-face nature is a fundamental element for the humanization of society, the productive development of the environment, and the socio-economic return that its territorial implementation produces” (p.3). The University of Alcalá states: “The University of Alcalá, as an academic institution, is based on the face-to-face teaching model. Therefore, any modification that may be necessary and affects the essence of this model will be temporary, proportional to the evolution of the health situation, and in response to the legal restrictions determined by the health authorities concerning the availability of space and its case of mobility or meeting” (p.2). Online teaching requirements For the development of online teaching, the ministry proposed three fundamental pillars: training in digital skills, the availability of spaces and resources to support online teaching, and the fight against the digital divide. Regarding digital skills training, the ministry established, as a mandatory element, the creation of training plans for teachers that contribute to developing an optimal quality blended and online education. In this sense, most Spanish universities include this aspect in their regulations (n = 15), except for universities such as Barcelona, Cantabria, Extremadura, Murcia, and Rioja. Among the various training activities mentioned by the universities, of particular note are the creation of free online courses or webinars aimed at developing digital competencies, using digital tools, and acquiring knowledge of new online teaching methodologies. The ministry also included the possibility of developing training plans for students. However, only a few universities (n = 6; Castilla-La-Mancha, Salamanca, Granada, Oviedo, Balearic Islands, and Valencia) considered this possibility. These plans consisted of developing different courses aimed at the knowledge and handling of the various digital tools made available to students. Finally, universities such as Oviedo and Granada go beyond all this by proposing training plans for administration and service employees. The following figure shows a group query showing the types of training plans contained in the contingency plans of the different universities (Figure 3). Concerning the availability of resources and spaces to support teaching, the ministry recommended the need for computer systems that would allow for the adequate implementation of virtual teaching. In this sense, and with the aim of achieving this goal, the universities applied two fundamental strategies: (1) the technological improvement of classrooms for the direct retransmission of classes, and (2) the expansion of virtual and technological resources of the universities (e.g., virtual platforms, software, and internet connection). Classroom improvements included introducing cameras, microphones, digital whiteboards, and other audiovisual equipment and advanced multimedia resources to support online or hybrid teaching. However, within this group, the measures mentioned by the Universities of Alcalá and Madrid are notable, that is, the creation of class recording studios and computer laboratories to facilitate student access to online teaching. In terms of virtual improvements, we note advances in the e-learning and moodle ecosystems, the refurbishment of platforms to support teaching and online evaluation, the improvement and extension of iCloud work systems, the increase of virtualization resources for remote access to practice software, the increase in the number of Microsoft Office and Blackboard Collaborate licenses, a new backup and security copy policy, and the upgrade of various videoconferencing systems such as Google Meet, Skype, or Zoom. Concerning the digital divide, the Ministry of Universities stressed the need to ensure connectivity and access to different technological resources for all university students, thus avoiding the digital divide and its possible consequences for educational equity. To this end, some universities (n = 7) implemented a series of measures such as the introduction of scholarships and grants to provide students with computer equipment or Internet connection cards; the development of computer lending services; and the adaptation of evaluation processes (University of Granada, Balearic Islands, La laguna, Complutense of Madrid, Navarra, Basque Country Vasco, and Sevilla). Likewise, within this group, five universities included in their contingency plans this type of assistance for teaching staff but in the form of loans, that is, loans of the technological resources necessary for carrying out online teaching. These universities are Seville, La Laguna, Balearic Islands, Basque Country, and Complutense de Madrid. Finally, and in the face of the economic crisis generated by the pandemic, some universities (the University of Granada and Basque Country) took other social measures to safeguard educational equity, such as allowing the payment of study fees in additional installments or even applying tuition fee waivers, COVID-19 cost-sharing assistance, and increased access to psychological support. Evaluation The area of evaluation is where there is the greatest disparity in actions between the universities. In general terms, the ministry recommends developing heterogeneous evaluation tests that allow for successfully assessing the acquisition of content, competencies, and learning. Despite this, it emphasizes the need to conduct face-to-face tests whenever the health situation permits. Following these recommendations, many universities prioritized face-to-face evaluation (n = 17), and only the Universities of Valencia and Murcia did not mention this possibility. The University of Murcia does not specify anything concerning the evaluation process, leaving this decision in the hands of the various departments. For the development of this type of evaluation, the different contingency plans of the other universities mention a series of strategies to ensure health safety. Among these measures are the maintenance of social distancing in the classrooms, the use of different exam rooms for the same group to avoid overcrowding in the classrooms, or, in case of lack of space, the establishment of different exam time slots for the same group, which help to avoid overcrowding in the classroom and conglomerations at the entrance and exit of the tests. In addition to this possibility, all the universities also considered different adaptations of the evaluation methodologies in the face of possible changes caused by the health situation. In this sense, the contingency plans of the different universities included two possible lines of action: the use of telematics for final exams or substitution of the final exams for other evaluation methodologies, mainly through continuous evaluation processes. Regarding the former, almost all universities considered the development of fully telematic final exams as the main adaptation (n = 13). In this case, universities underline the importance of developing systems to ensure academic integrity and avoid possible litigation processes. Concerning the second possibility, many universities opted for replacing final exams (in-person or online) with another type of evaluation (n = 12). In this case, the universities emphasize the importance of developing systems that ensure the maintenance of academic integrity. In this sense, the universities opted for continuous and formative assessment without the need to administer final exams. Among all the universities that mentioned this option, we should highlight the case of the University of Granada, which went a step further by developing a document with alternative methodologies and instruments for non-face-to-face evaluation. The following table shows the various evaluation methods considered in the contingency plans of the different universities (Table 4).Table 4. Types of evaluation according to university. University/Institution Face-to-face evaluation Online evaluation Other types of evaluation University of Alcalá X X X University of Barcelona X University of Cantabria X University of Castilla-La Mancha X X University Complutense of Madrid X X X University of Extremadura X X University of Granada X X X University of Islas Baleares X X University of La Laguna X X X University of La Rioja X X X University of Murcia University of Navarra X X University of Oviedo X X University of País Vasco X X University of Salamanca X X University of Santiago de Compostela X X X University of Seville X X X University of Valencia X X University of Zaragoza X X Total 16 13 12 Source: Authors’ own. Conclusions The purpose of this work was to examine the political and educational measures implemented by various Spanish universities during the pandemic. To this end, a documentary analysis of the main regulations, instructions, and guidelines published during this period was carried out. A series of conclusions were drawn from this analysis, which we will describe next. As mentioned above, the universities have the autonomy to promote actions adapted to their particular circumstances. Despite this, in the face of a health crisis such as the one resulting from COVID-19, our findings show that universities also consider joint and coordinated action essential in this situation. This leads to better institutional strengthening and development. In this regard, we can also observe that Spain has followed a similar line of action to the rest of the countries in the world, focusing its adaptations on aspects such as adjusting teaching to an online format, making assessment processes more flexible, and developing online platforms to facilitate teaching (Moorhouse, 2020; Valeeva and Kalimullin, 2021; Xhelili et al., 2021). One of the most important recommendations at the international level was related to student access to the internet and teacher and student training in technological resources and digital platforms. The aim of this approach was to favor and facilitate the online teaching-learning processes developed during the pandemic. This is in line with practices developed at the Spanish level, following the motto that “no one is left behind” (Reche et al., 2021). This apparent global coordination is due, in part, to the collaboration between institutions such as the International Association of Universities (IAUs), the International Institute for Higher Education in Latin America and the Caribbean (UNESCO IESALC, 2020), and the Inter-American Organization for Higher Education (IOHE). These were responsible not only for proposing possible solutions or recommendations but also for sharing good management practices developed by university institutions during this crisis. However, despite these general guidelines that seem to have been considered by all countries, the Spanish context differs in one essential aspect: its staunch defense of face-to-face teaching. Although the Spanish university system has proposed online teaching as the main tool in the face of this crisis, the documents analyzed show a staunch defense of face-to-face teaching in the classroom, rejecting the idea of orienting its services towards purely virtual environments. This is evidence of a conception of the Spanish university system anchored in the pre-digital era, focusing on physical, face-to-face, and synchronous contact. Thus, Spanish universities resist the dynamics advocated in the scientific literature, in which a hybrid learning model is promoted, interspersing face-to-face and virtual sessions (Li et al., 2021; Wirani and Manurung, 2020). Furthermore, it is worth noting that among the measures proposed by the ministry, there is no mention of educational policy and measures following the pandemic. This suggests that the decisions taken as a result of the pandemic were of an urgent nature and were simply a means of responding to the health crisis without any intention of opening a debate on the digital transformation of universities. This analysis, therefore, demonstrates the clear presential nature of the Spanish university system. Implications for educational authorities and professional practice After a brief summary of these general orientations and actions developed nationally and internationally, we consider it interesting to point out a series of political and educational implications that could help future health crises or social/natural disasters.- Designing learning activities that are adapted to different learning environments. Due to the emergence of this new health crisis, many lessons must be considered, including the need to adapt university teaching processes to virtual scenarios. In this sense, some recommendations and didactic guidelines might encourage the use of new hybrid methodologies that intersperse face-to-face and online spaces within the teaching plans/guides. - Promotion of digital pedagogies in the curriculum. The advent of the pandemic and the “new normal” has fostered new ways of teaching that focus on networked communication, digital narratives, performance, and social networks. University teachers should therefore consider these new methodological approaches. - Evaluation during the pandemic has clearly pushed the teaching process to the limit. This challenge has seriously raised questions about the maturity of the digital transformation strategies in the university system. Online assessment has clearly laid bare the idea that digital transformation is not the same as process digitalization and that technology advances faster than its acceptance and legal adequacy (González-González et al., 2020). For this same reason, we believe that university governance teams have much to reflect on to integrate technology into their educational models and make advances in hybrid modalities that know how to take advantage of resources and means without rejecting the best face-to-face and virtual learning practices. To this end, it is also necessary to rethink teacher training plans, both in terms of the contents and competencies to be promoted and in the teaching formats in which they are to be developed (García-Peñalvo, 2020). - The future use of methodological adaptations. The changes promoted by the universities included in this article may become especially relevant and useful if we return to scenarios similar to the one experienced amid the COVID-19 crisis. These experiences also allow us to respond to the needs of students whose academic activity has been modified due to work or personal changes derived from the pandemic. However, this requires a modification in the planning of the teaching methodology and existing resources, as well as the legal regulations on data protection. Furthermore, greater use of technology implies transformation of the teaching-learning processes, which requires prior work by multidisciplinary teams of specialists in information security, networks, and programming beyond the teaching exercise (Fluck, 2019; Pathak, 2016). - Reorientation of university teaching and research post-COVID-19. The health crisis has opened up a new field of study in education. This makes the need to investigate the potential and limitations of e-learning in times of pandemics a priority. This adds value to research aimed at improving university teaching in the aftermath of the COVID-19 pandemic. In addition, this health crisis should be seen as a catalyst for the digitization of the university system. - There still remains a struggle for gender equality, equity, and inclusion in university classrooms and at the professional level within higher education. It is essential to make visible the gender, social, and economic inequalities in the university environment, which have come to the forefront during the pandemic among students, teaching staff, and families. It would be interesting to approach this action from a feminist perspective and with strong social justice values. - Teacher training in higher education. This aspect is a key and decisive factor in achieving a true curricular adaptation to new circumstances and future situations. For this reason, training in new hybrid educational methodologies could be the way of the future and bring continuity and flexibility to the online work that teachers and students need today more than ever. - The provision of emotional support to students and their families. This is especially important for those who might require more educational support in the proposed initiatives and activities. In addition, it is important to consider and assess whether students have sufficient resources in their environment to favor real learning, including technological tools, support staff, and educational support materials. - Strengthening the resilience of education systems to achieve equitable and sustainable development. Building resilient education systems is a fundamental axis for change. Learning from the lessons of the pandemic will ensure the equitable and sustainable development of higher education. Moreover, this resilience must be strengthened through strong and distributed leadership networks. - Coordination and consolidated leadership for day after and future pandemics. The COVID-19 crisis has shown us the important changes and new trends in leadership that should be approached from a cross-cutting perspective and with international synergies for the common good. Although this is a historical challenge, it is also an opportunity to strengthen leadership networks in higher education. According to current research in this area, leadership based on horizontality, social justice, and collective commitment would be key in these adverse times and help us to face the ever-closer Day After. - Providing technological educational resources to the most disadvantaged groups. The current pandemic has provided yet another scenario of social and economic inequalities of the student body in higher education. This, of course, has led to a loss in enrolment numbers and an increase in the number of students who have decided to give up their studies due to a lack of financial resources. However, it is also important to mention other shortcomings regarding the resources necessary to develop virtual teaching in this period. In this case, we consider that technological resources applied to education are a great pillar of action to alleviate the inaccessibility of education during this health crisis. In this regard, laptops, tablets, digital devices, and the provision of a free network would provide much-needed support for university students in these types of circumstances. Javier Mula-Falcón is teacher and researcher at the University of Granada. His main line of research focuses on the construction of professional identity and higher education. He is a member of FYDAD research group and RILME Research Network. Cristina Cruz-González is teacher and researcher at the University of Granada. Her main line of research focuses on the construction of professional identity and educational leadership. She is a member of FORCE research group and RILME Research Network. Jesús Domingo Segovia is Doctor in Philosophy and Educational Sciences and University Professor at the Faculty of Education, University of Granada (Spain). He is specialized in (auto)biographical-narrative methodology and the areas of curricular, professional, institutional and family counselling, curricular innovation and development, attention to diversity and processes of educational and social vulnerability. He is member of FORCE research group and RILME Research Network. He is part of the 3rd Strand of the ISSPP project (International Successful School Principalship Project). Carmen Lucena Rodríguez is teacher and researcher at the University of Granada. Her main line of research focuses on the construction of professional identity and educational leadership. She is a member of FORCE research group and RILME Research Network. ORCID iDs Javier Mula-Falcón https://orcid.org/0000-0002-1977-7026 Cristina Cruz-González https://orcid.org/0000-0002-2019-6245 Jesús Domingo-Segovia https://orcid.org/0000-0002-8319-5127 Carmen Lucena https://orcid.org/0000-0003-4451-337X The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the State Research Agency, Spanish Ministry of Science and Innovation, through the project “The influence of neoliberalism on academic identities and on the level of professional satisfaction”—NEOACADEMIC—(PID2019-105631GA-I00/SRA (State Research Agency)/10.13039/501100011033); and by the R+D+i Project in the framework of the FEDER Operational Programme ‘Early career academics in Andalusian Universities: Academic identities, quantified and digitised.’ (B_SEJ-534-UGR20). It also receives funding from the Ministry of Universities (Spain) through the University Teacher Training Grants Programme (FPU19/00942). ==== Refs References Area-Moreira M Bethencourt-Aguilar A Martín-Gómez S , et al. (2021) Análisis de las políticas de enseñanza universitaria en España en tiempos de COVID-19. La presencialidad adaptada. Revista de Educación a Distancia (RED) 21 (65 ): 12–28. Babbar M Gupta T (2021) Response of educational institutions to COVID-19 pandemic: an inter-country comparison. Policy Futures in Education 20 : 469–491. DOI: 10.1177/14782103211021937. Bardin L (1992) Análisis de contenido. Madrid: Ediciones Akal. Blankenberger B Williams M (2020) COVID and the impact on higher education: the essential role of integrity and accountability. Administrative Theory and Praxis 42 (3 ): 404–423. Boer H (2021) COVID-19 in Dutch higher education. Studies in Higher Education 46 (1 ): 96–106. Bonilla-Guachamín J (2020) Las dos caras de la educación en el COVID-19. CienciAmérica 9 (2 ): 89–98. Braun V Clarke V (2006) Using thematic analysis in psychology. Qualitative Research in Psychology 3 (2 ): 77–101. DOI: 10.1191/1478088706qp063oa. Brewer M Van Kessel G Sanderson B , et al. (2019) Resilience in higher education students: a scoping review. Higher Education Research and Development 38 (6 ): 1105–1120. Camilleri M (2021) Evaluating Service Quality and Performance of Higher Education Institutions: A Systematic Review and a Post-COVID-19 Outlook. International Journal of Quality and Service Sciences 13 (2 ): 268–281. Crawford J Butler-Henderson K Rudolph J et al . (2020) COVID-19: 20 countries’ higher education intra-period digital pedagogy responses. Journal of Applied Learning and Teaching JALT 3 (1 ): 9–28. doi: 10.37074/jalt.2020.3.1.7. CRUE (2020) La Universidad frente a la pandemia. Available at: https://www.crue.org/wp-content/uploads/2020/12/La-Universidad-frente-a-la-Pandemia.pdf. Darras K Spouge R Bruin A , et al. (2021) Undergraduate radiology education during the COVID-19 pandemic: a review of teaching and learning strategies. Canadian Association of Radiologists Journal 72 (2 ): 194–200.32749165 DeMatthews D Knight D Reyes P , et al. (2020) From the field: education research during a pandemic. Educational Researcher 49 (6 ): 398–402. El Masri A Sabzalieva E (2020) Dealing with disruption, rethinking recovery: policy responses to the COVID-19 pandemic in higher education. Policy Design and Practice 3 (3 ): 312–333. Engzell P Frey A Verhagen M (2021) Learning loss due to school closures during the COVID-19 pandemic. Proceedings of the National Academy of Sciences 118 (17 ). Fluck A (2019) An International review of exam technologies and impact. Computers and Education 132 : 1–15. DOI: 10.1016/j.compedu.2018.12.008. García-Peñalvo F (2020) La Metodología Antes que la Tecnología para Afrontar la Nueva Normalidad Docente en la Universidad. Salamanca: Universidad de Salamanca. Geldsetzer P (2020) Use of rapid online surveys to assess people’s perceptions during infectious disease outbreaks: a cross-sectional survey on COVID-19. Journal of Medical Internet Research 22 (4 ): e18790. DOI: 10.2196/18790.32240094 González-González C Infante-Moro A Infante-Moro JC (2020) Implementation of e-proctoring in online teaching: a study about motivational factors. Sustainability 12 (8 ): 34–48. DOI: 10.3390/su12083488. Grossi M Elias M Chamon C , et al. (2018). The educational potentialities of the virtual learning environments moodle and canvas: a comparative study. International Journal of Information and Education Technology 8 (7 ): 514–519. Joaquin J Biana H Dacela A (2020) The Philippine higher education sector in the time of COVID-19. Frontiers in Education 5 : 57–63. DOI: 10.3389/feduc.2020.576371. Karakose T (2021) The impact of the COVID-19 epidemic on higher education: opportunities and implications for policy and practice. Educational Process: International Journal 10 (1 ): 7–12. DOI: 10.22521/edupij.2021.101.1. Karalis T (2020) Planning and evaluation during educational disruption: lessons learned from COVID-19 pandemic for treatment of emergencies in education. European Journal of Education Studies 7 (1 ): 23–36. Li Q Li Z Han J (2021) A hybrid learning pedagogy for surmounting the challenges of the COVID-19 pandemic in the performing arts education. Education and Information Technologies 26 : 1–21.33424417 Means A (2013) Creativity and the biopolitical commons in secondary and higher education. Policy Futures in Education 11 (1 ): 47–58. DOI: 10.2304/pfie.2013.11.1.47. Miles M Huberman A (1994) Qualitative data analysis: An expanded source book. Thousand Oaks, Sage. Ministry of Universities (2020) Medidas de Prevención, Higiene y Promoción de la Salud Frente a COVID-19 para Centros Universitarios en el Curso 2020–2021. https://www.mscbs.gob.es/profesionales/saludPublica/ccayes/alertasActual/nCov/documentos/COVID19_Medidas_Centros_Universitarios_11-03-21.pdf. Mishra L Gupta T Shree A (2020) Online teaching-learning in higher education during lockdown period of COVID-19 pandemic. International Journal of Educational Research Open 1 : 100012, DOI: 10.1016/j.ijedro.2020.100012.35059663 Moorhouse B (2020) Adaptations to a face-to-face initial teacher education course ‘forced’online due to the COVID-19 pandemic. Journal of Education for Teaching, 46 (4 ): 609–611. Moye C (2021) Pandemics: the politics of disparities and social justice in a virtual world. In The Black Experience and Navigating Higher Education Through a Virtual World. Hershey, PA: IGI Global. 141–162. Organic Law 4/2007, of April 12, 2007, which amends Organic Law 6/2001, of December 21, 2001, on Universities . Pathak B (2016) Emerging online educational models and the transformation of traditional universities. Electronic Markets 26 (4 ): 315–321. DOI: 10.1007/s12525-016-0223-4. Pather N Blyth P Chapman J , et al. , (2020) Forced disruption of anatomy education in Australia and New Zealand: an acute response to the COVID-19 pandemic. Anatomical Sciences Education 13 (3 ): 284–300.32306555 Reche M Marín J Navas-Parejo M , et al. (2021) El impacto del estado de alarma decretado por la COVID-19 en la inclusión educativa. Texto Livre: Linguagem e Tecnologia 14 (2 ): 42–54. Sahu P (2020) Closure of universities due to coronavirus disease 2019 (COVID-19): impact on education and mental health of students and academic staff. Cureus 12 (4 ): e7541.32377489 Thomas J Foster H (2020) Higher education institutions respond to epidemics. History of Education Quarterly 60 (2 ): 185–201. Toledo P (2020) Pandemia COVID-19: educación a distancia. O las distancias en la educación. Revista Internacional de Educación para la Justicia Social 9 (3 ): 1–3. Toquero C (2021) Emergency remote education experiment amid COVID-19 pandemic. IJERI: International Journal of Educational Research and Innovation 15 : 162–176. doi: 10.46661/ijeri.5113. UNESCO (2020) Education: From Disruption to Recovery. Available at: https://bit.ly/3evM4sL UNESCO IESALC (2020) COVID-19 and Higher Education: Today and Tomorrow. Impact Analysis, Policy Responses and Recommendations. Available online at: http://www.guninetwork.org/publication/report-covid-19-and-higher-education-today-and-tomorrow-impact-analysis-policy-responses University Complutense of Madrid (2020) Marco Estratégico de Docencia para el Curso 2020/2021. https://www.ucm.es/file/marcoestrategicoucm-1 University of Alcalá (2020) Plan de Actuación de la Universidad de Alcalá para la Adecuación de la Actividad Universitaria en el Curso 2020-2021. https://www.uah.es/export/sites/uah/.galleries/documentos/Plan-de-Actuacion_Curso-2020-2021.pdf University of Barcelona (2020) Plan de Contingencia de la Universidad de Barcelona Ante la Crisis Sanitaria por la COVID-19. https://www.ub.edu/web/ub/galeries/documents/universitat/coronavirus/pla-de-contingencia-20209731.pdf University of Cantabria (2020) Procedimiento de Retorno a la Actividad Presencial Tras el Confinamiento Decretado por el Estado de Alerta Sanitaria Motivado por COVID-19. https://web.unican.es/Documents/covid19/Protocolo-de-retorno-actividad-UC.pdf#search=covid University of Castilla-La-Mancha (2020) Plan de Contingencia Académico de la UCLM para el Desarrollo del curso 2020/21. https://www.uclm.es/-/media/Files/A01-Asistencia-Direccion/A01-200-Gerencia/COVID-19/Plan-de-Contingencia-Acadmico-de-la-UCLM-para-el-desarrollo-del-curso-20-21.ashx?la=es University of Extremadura (2020) Procedimiento de Presencialidad del curso 20-21 Adaptada a los Requisitos de “Nueva Normalidad” COVID-19. https://www.unex.es/organizacion/gobierno/vicerrectorados/vicecal/archivos/ficheros/ficheros-covid-19/nueva-normalidad-covid19/P_3_1_Plan_curso_20_21_Aprobado_CdG.pdf University of Granada (2020) Plan de Contingencia para la Docencia y Evaluación no Presencial de la Universidad de Granada. https://canal.ugr.es/wp-content/uploads/2020/04/Plan_de_Contingencia_para_la_Docencia_y_Evaluacio%CC%81n_no_presencial-1.pdf University of Islas Baleares (2020) Plan de Actuación de la Universitat de les Illes Balears para el año Académico 2020-21 Ante la Pandemia por COVID-19. https://coronavirus.uib.es/digitalAssets/609/609955_Pla-dactuaciA-curs-2020-21.pdf University of la Laguna (2020) Criterios Generales para la Docencia y la Evaluación en Condiciones de Presencialidad Adaptada Durante el Curso 2020-2021. https://drive.google.com/file/d/1Wvm3GowwUtlA6F78-UWn2_7KjA8NhplQ/view University of la Rioja (2020) Plan de Contingencia del curso 2020-2021 para la Adaptación de la Actividad Docente a los Requerimientos de la Situación Sanitaria. https://www.unirioja.es/servicios/opp/plandoc/2021/plancon.shtml University of Murcia (2020) Recomendación de un Plan de Contingencia 3 con un Escenario de Semipresencialidad Reducida que Permita Reducir el Riesgo y Preservar las Actividades Académicas y de Investigación de Presencialidad Necesaria e Imprescindible. https://www.um.es/web/universidad/contenido/coronavirus/pc3 University of Navarra (2020) Plan de Contingencia de la Universidad Pública de Navarra (curso 2020-21). https://www2.unavarra.es/gesadj/seccionActualidad/coronavirus/PLAN_DE_CONTINGENCIA_UPNAv1.pdf University of Oviedo (2020) Plan de Adaptación de la Actividad Docente para el curso 2020- 2021. https://www.uniovi.es/ast/-/plan-de-adaptacion-de-la-actividad-docente-para-el-curso-2020-2021 University of País Vasco (2020) Orientaciones para la Planificación de la Enseñanza y el Aprendizaje para el curso 2020-2021. https://www.ehu.eus/es/orientaciones-para-la-planificaci%C3%B3n-de-la-ense%C3%B1anza-y-el-aprendizaje University of Salamanca (2020) Modelo de Adaptación de la Docencia en la USAL curso 2020-2021. https://www.usal.es/files/Modelo-Docencia-2020-2021-20200918.pdf University of Santiago de Compostela (2020) Directrices para el Desarrollo de la Enseñanza Segura para el curso 2020-2021. Available at: https://www.usc.gal/export9/sites/webinstitucional/gl/web/descargas/20_06_26_Directrices-docencia-2020-2021.pdf. University of Sevilla (2020) Criterios Académicos para la Adaptación de las Titulaciones Oficiales de la Universidad de Sevilla a las Exigencias Sanitarias Causadas por la COVID-19 Durante el curso Académico 2020-2021. https://www.us.es/sites/default/files/comunicacion/coronavirus/Criterios-academicos-US-curso-20-21.pdf University of Valencia (2020) Adaptación de la Docencia de las Titulaciones Oficiales de la Universidad de Valencia para el curso 2020-21. https://www.uv.es/coronavirus/Adaptacion_docencia_titulaciones_oficiales_UV_2020_21_CG.pdf University of Zaragoza (2020) Acuerdo de 6 de Julio de 2020, del Consejo de Gobierno de la Universidad de Zaragoza, por el que se Adoptan Directrices para Afrontar el Desarrollo de la Docencia en el curso Académico 2020-21, en la Situación de Nueva Normalidad. https://www.unizar.es/sg/pdf/acuerdos/2020/2020-07-06/2%20Acuerdo%20Directrices%20Docencia.pdf Valeeva R Kalimullin A (2021) Adapting or changing: the COVID-19 pandemic and teacher education in Russia. Education Sciences 11 (8 ): 408. Wirani N Manurung A (2020) The importance of using a web-based learning model to prevent the spread of COVID 19. Al’adzkiya International of Education and Sosial (AIoES) Journal 1 (1 ): 16–24. World Health Organization [WHO] (2020) WHO Coronavirus Disease (COVID-19) Dashboard. Available at: https://covid19.who.int/table Xhelili P Ibrahimi E Rruci E , et al. (2021) Adaptation and perception of online learning during COVID-19 pandemic by Albanian University students. International Journal on Studies in Education 3 (2 ): 103–111. Zhou L Wu S Zhou M , et al. (2020) ‘School’s out, but class’ on’, the largest online education in the world today: taking China’s practical exploration during the COVID-19 epidemic prevention and control as an example. Best Evid Chin Edu 4 (2 ): 501–519.
PMC009xxxxxx/PMC9637906.txt	==== Front J Soc Pers Relat J Soc Pers Relat spspr SPR Journal of Social and Personal Relationships 0265-4075 1460-3608 SAGE Publications Sage UK: London, England 10.1177_02654075221130785 10.1177/02654075221130785 Articles Daily stress, family functioning and mental health among Palestinian couples in Israel during COVID-19: A moderated mediation model https://orcid.org/0000-0001-5626-4679 Hassan-Abbas Niveen M. PhD Department of Special Education and Psychology, Department of Behavioral Sciences, 61315 Zefat Academic College , Safed, Israel Niveen M. Hassan-Abbas, PhD, Department of Special Education and Psychology, Department of Behavioral Sciences, Zefat Academic College, 11 Jerusalem St., P.O.B 160, Safed 13206, Israel. Emails; [email protected];[email protected] 4 11 2022 6 2023 4 11 2022 40 6 17701791 © The Author(s) 2022 2022 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. The COVID-19 pandemic created a range of stressors, among them difficulties related to work conditions, financial changes, lack of childcare, and confinement or isolation due to social distancing. Among families and married individuals, these stressors were often expressed in additional daily hassles, with an influence on mental health. This study examined two moderated mediation models based on Bodenmann’s systemic-transactional stress model. Specifically, the models tested the hypothesis that intra-dyadic stress mediates the association between extra-dyadic stress and mental health, while two measures of family functioning, cohesion and flexibility, moderate the relationship between extra and intra-dyadic stress. Participants were 480 Palestinian adults in Israel who completed self-report questionnaires. All were in opposite-sex marriages and identified as either cisgender women or cisgender men. The results showed partial mediation patterns supporting both models, indicating that family cohesion and flexibility weakened the mediating effect of intra-dyadic stress on the relationship between extra-dyadic stress and mental health. These findings increase our understanding of the variables that affected mental health during the pandemic, and suggest that when faced with extra-dyadic stress, married individuals with good family environments are less likely to experience high levels of intra-dyadic stress, which is in turn associated with preserved mental health. Limitations and implications for planning interventions for couples and families during the pandemic are discussed. Palestinian families in Israel COVID-19 pandemic family cohesion and flexibility extra-dyadic stress intra-dyadic stress mental health typesetterts10 ==== Body pmcLike other large-scale adversities, the COVID-19 pandemic created a range of stressors, among them difficulties related to work conditions, such as doing paid work while caring for family at home, financial changes, lack of childcare, and confinement or isolation due to social distancing (Craig & Churchill, 2020; Prime et al., 2020). Among families and married individuals, these stressors were often expressed in additional daily hassles. Not surprisingly, the months following the outbreak of the pandemic were also characterized by a clear rise in negative psychological outcomes, including anxiety, depression, and distress among both individuals (Barzilay et al., 2020; Forte et al., 2020; Kimhi et al., 2020; Polizzi et al., 2020; Ye et al., 2022) and families (e.g., Goldberg et al., 2021; Gray et al., 2020). Several decades of research have consistently shown that hassles, which have been associated with perceived daily stress (Bodenmann et al., 2006), pose risks both for family relationships and for the functioning and mental health of individuals within families (Falconier et al., 2015). High levels of perceived daily stress are related to greater anxiety and depression, lower mental health in general (D’Angelo & Wierzbicki, 2003; Parrish et al., 2011), increased psychopathological symptoms, and decreased subjective well-being (Schönfeld et al., 2019). The systemic-transactional model (STM; Bodenmann, 1995; 1997, 2005), is a systems-oriented model addressing stress processes in couples’ relationships, including the association between hassles and mental health. The approach is based on the work of Folkman and Lazarus (1980), which highlighted the subjectivity of coping with stress. According to their prominent and internationally recognized transactional theory of stress (Lazarus & Folkman, 1984), the perceived stress experienced by an individual is largely determined by how that individual appraises the situation and her or his own resources to cope with it. As such, individuals with different coping capacities will experience different levels of perceived stress under similar objective environmental stressors. The STM emphasizes the distinction between extra-dyadic stress and intra-dyadic stress. The former refers to tension that originates outside of a relationship, such as social and economic strains, work stress, conflicts with neighbors, friends, or problems with authorities. Meanwhile, intra-dyadic stress refers to tension within the relationship, such as problems with the partner, overload with family responsibilities, insufficient time for family, disagreements about task-sharing in the household, and feeling bothered by some of partner’s habits. According to the STM, extra-dyadic stress from daily hassles can have a direct negative impact on individual health and on the couples’ relationship (Bodenmann, 1997). This claim has been supported in several studies with a range of outcomes related to psychological well-being (Falconier et al., 2015; Serido et al., 2004). Furthermore, according to the STM, external stress affects mental health not only directly but also indirectly by increasing intra-dyadic stress (Bodenmann et al., 2016; Falconier et al., 2015; Neff & Karney, 2017). Namely, when extra-dyadic stress spills over into the dyad, the couple’s dynamics can be negatively affected, which also contributes to decreased mental health (Falconier et al., 2015). In this context, Neff and Karney (2017) have argued that stressful contexts undermine marital well-being through two routes. In the first route, external stressors create additional problems by diverting time and attention away from activities that promote intimacy between partners in the marriage. In the second, external stress can make it difficult for spouses to cope with the increased problems by draining them of the energy and resources necessary for responding constructively. When individuals have to cope with greater external demands, they report being more distracted and less responsive when interacting with their partners (Story & Repetti, 2006), and when they do manage to make time for interacting, they often allocate that time to resolving their stressors (Randall & Bodenmann, 2009). In an example provided by Neff and Karney (2017), a couple experiencing serious financial strains might spend their limited time together negotiating the household budget, instead of more pleasurable pursuits that foster intimacy. It follows that when extra-dyadic stress does not increase intra-dyadic stress, better outcomes can be expected. According to the STM, there are mechanisms that prevent extra-dyadic stress from increasing intra-dyadic stress, for example, provision of support and joint efforts to deal with common stressors (Bodenmann et al., 2016). Accordingly, we can assume that additional characteristics of family functioning interact with extra-dyadic stress in determining intra-dyadic stress. The current study therefore examined the possibility that two family functioning measures, cohesion and flexibility, would influence the association between extra-dyadic stress and intra-dyadic stress. This analysis was part of a broader model examining the ways in which extra-dyadic stress from daily hassles affects individual mental health through increased intra-dyadic stress. Essentially, family functioning is considered a potential protective factor that can buffer the adverse effects of extra-dyadic stress on intra-dyadic stress. The family functioning measures examined here, cohesion and flexibility, are broadly discussed in the Circumplex Model of Marital and Family Systems (Olson et al., 1979), as central variables that define family interactions (Olson, 2000). Cohesion, which involves emotional bonding between family members, is positively correlated to the provision of functional and emotional support (Wang et al., 2015). Flexibility relates to the quality and expression of the family’s leadership, organization, roles, and rules. It has been associated with effective adaptation to life changes and stressful events among families (García-Huidobro et al., 2012; Koutra et al., 2016; Wang et al., 2015). Together, cohesion and flexibility have been shown to create a balance between stability and adaptation to change, leading to optimal functioning (Olson, 1993; Olson & Gorall, 2006). The theoretical premise of the current study is that families that adapt to change while remaining close experience less perceived stress. Various studies examining family functioning during times of distress support this premise. For example, earlier work on the family environments of patients with traumatic brain injuries shows that positive family functioning improves coping and enables thriving (Perrin et al., 2013; Sander et al., 2002; Stevens et al., 2013). Studies have also shown that better family functioning encouraged effective coping processes during major epidemics (Chang et al., 2015; Neo et al., 2016) and when a family member had a life-threatening medical condition (Harris & Zakowski, 2003). Berryhill et al. (2018) also found that cohesive-flexible family functioning was associated with better coping resources, including positive communication and self-compassion. Other work has shown direct relationships between measures of family functioning and perceived daily stress. Pollock et al. (2015) found that cohesion and flexibility were directly and negatively related to perceived stress from daily hassles. Sheidow et al. (2014) showed that youths from struggling families, which were low in family cohesion, positive communication, support, and organization, were less resilient to stress from daily hassles. Studies specifically addressing the COVID-19 pandemic have also shown family functioning to be associated with perceived stress, both directly and as presumably moderated by coping. Salin et al. (2020) showed that agreement regarding everyday practices, sharing responsibilities, and confidence in managing life pressures promoted better coping with lockdown-related stressors, with flexibility emerging as a crucial facilitator. Goldberg et al. (2021) showed that use of strategies aimed at maintaining or enhancing relationship health decreased relationship and parenting stress. Similarly, both Hu et al. (2020) and Mohindra et al. (2020) showed that healthy family environments were associated with the provision of family support, which encouraged effective coping among individual family members. Finally, Ye et al. (2022) showed a direct negative association between family cohesion and perceived stress during the pandemic. Cultural context The main goal of the current study was not cultural comparison. Indeed, the literature supporting the proposed models is not limited to a particular cultural group. However, it is noteworthy that the study sample comprised married individuals from the Palestinian society in Israel, a population that has rarely been studied. A short description of broad sociocultural characteristics is therefore provided, with a focus on stress and family functioning, to contextualize the study. At 21% of Israel’s total population, Palestinian society constitutes a minority (Israeli Central Bureau of Israel Central Bureau of Statistics, 2019) and is therefore subjected to the stress involved in balancing the ubiquitous demands of the dominant and minority cultures (Hennon et al., 2008; Peterson, 2017). This stress has been shown to affect family relationships and functioning (Peterson, 2017). While Palestinian society in Israel tends to have traditional attitudes toward marriage and gender roles, with an unequal division of labor in the home and family (Abu-Baker, 2003), its proximity to the more modern views of the majority population has led to demographic, social, and economic changes, including the educational and economic empowerment of women. In addition, Palestinian society, like other Arab cultures, is largely collectivistic, and thus often characterized by close relationships between relatives, friends, and neighbors (Azaiza, 2008a). Furthermore, the Palestinian population has more limited access to professional mental healthcare services (Al-Krenawi & Graham, 2005), though as an ethnic minority they have a greater need for such services (Azaiza, 2008b). Due in part to this increased vulnerability, we might expect the limitations on extended family support experienced during the COVID-19 pandemic to affect the Palestinian population disproportionately, making cohesion and flexibility in the nuclear family particularly important. Current study and hypotheses Based on the aforementioned findings, the current study addressed the interplay between extra-dyadic stress, intra-dyadic stress, family functioning, and mental health among married individuals during the COVID-19 pandemic. Specifically, the study examined whether intra-dyadic stress mediated the relationship between extra-dyadic stress and mental health, and whether family functioning, as measured by cohesion and flexibility, moderated the relationship between extra-dyadic and intra-dyadic stress. Two models were tested, one for each of the moderator variables (family cohesion and family flexibility). The hypotheses were as follows: (1) extra-dyadic stress would be negatively associated with mental health, (2) intra-dyadic stress would partially mediate the relationship between extra-dyadic stress and mental health, and (3) family functioning (cohesion and flexibility) would moderate the relationship between extra-dyadic stress and intra-dyadic stress. Methods Participants and procedure Data for this study were taken from a larger survey on family coping during the COVID-19 pandemic among 480 Palestinian adults in opposite-sex marriages, who identified as either cisgender women or cisgender men (see Table 1), from different regions in Israel. Participants were recruited through social media to complete an online survey. To be included, participants had to be married and living with their spouse (divorced, separated, and widowed individuals were excluded), have at least one child, and have access to a smartphone, personal computer, or laptop and an Internet connection. An attempt was made to represent a broad sociodemographic range, with respect to age, gender, years of marriage, number of children, place of residence, and socioeconomic status. The sociodemographic characteristics of the sample are presented in Table 1.Table 1. Socio-demographic Characteristics of the Sample. Variable N % M (SD) Gender Male 141 29% Female 339 71% Age 38.3 (9.7) 18–29 89 18.5% 30–39 190 39.6% 40–49 143 29.8% 50+ 58 12.1% Education Elementary/high school 149 31% Post-secondary education 43 9% B.A. 165 35% M.A.+ 107 22% Other 16 3% Religion Muslim 353 74% Christian 34 7% Druze 91 19% Other 2 0% Marriage duration (1–54) 14.7 (9.5) Number of children (1–10) 2.8 (1.3) Participant employment Unemployed Employed Self-employed Student Pensioner Soldier Other 74 273 82 19 3 5 24 15.4% 56.8% 17.1% 4% .6% 1% 5% Average family income before the pandemic Far below average 75 16% Under average 83 17% Average 162 34% Above average 122 25% Far above average 38 8% Financial damage due to the pandemic None at all 122 26% Minor damage 139 29% Medium damage 119 25% High damage 63 13% Major damage 37 7% The COVID-19 pandemic began to spread in Israel in January 2020. Between March 15 and May 7, 2020, the Israeli government implemented an overall lockdown policy and required the entire population, with the exception of essential service providers, to leave their homes only for necessary provisions. Data for this study were collected just after the general lockdown was lifted, when the public was gradually allowed to resume routine functioning. Participants were asked to complete self-report questionnaires that addressed coping and stress since the outbreak of the pandemic, including the first lockdown. The study was approved by the institutional Ethics Committee at the college where it was conducted. Participants received a brief explanation regarding the study and were assured that anonymity and confidentiality would be maintained. All participants signed an informed consent form before completing the study questionnaire. Instruments As part of the larger study, participants completed a self-administered multi-component questionnaire addressing a range of family-related issues. The components used in the current study are described below. Apart from the sociodemographic variables, which were originally written in Arabic, all the measures were translated from English into Arabic using the following method. In the first phase, the questionnaire was translated into Arabic by the author. In the second stage, another professional in the field was asked to compare the Arabic version with the English version, to assess the questionnaire with respect to overall clarity and the clarity of specific words and instructions. In the third stage, the author prepared the final Arabic version of the questionnaire based on comments received from the additional professional. Family functioning The third edition of the Family Adaptability and Cohesion Evaluation Scale (FACES Ⅲ, 1985), developed by Olson et al. (1985), provided the two measures of perceived family functioning: cohesion and flexibility. The 20-item scale includes 10 items for each of the two factors. Family cohesion items address perceived within-family connectedness, unity, and emotional bonding (e.g., “we ask each other for help”; “we feel close to each other”; “togetherness is a top priority”). Family flexibility items address the perceived ability of the family to adjust its rules, provide structure, and adjust relationship patterns in response to changes (e.g., “it is hard to identify the leaders in our family”; “we shift household responsibilities from person to person”; “we try new ways of dealing with problems”). Participants rated the relative truth of each statement on a 5-point Likert scale ranging from 1 (Almost never) to 5 (Almost always). The scale was analyzed as a linear measure, with high scores in cohesion and flexibility indicating more functional family relationships (Olson, 1991). In the current study, Cronbach’s alpha values for cohesion and flexibility were .92 and .85, respectively. Extra-dyadic and intra-dyadic stress from daily hassles The basis for the daily stress measure used in the current study was the Hassles Scale developed by Kanner et al. (1981), which includes 118 items that assess various aspects of perceived daily stress. Bodenmann et al. (2006) previously employed a shortened version of the original Hassles Scale, called the Multidimensional Stress Questionnaire for Couples (MSQ-C; see also Falconier et al., 2015). Of the 37 items, they defined 29 as representing stress “external to the dyad” and 8 as representing stress “internal to the dyad.” In the current study, 8 items from each of the two categories proposed by Bodenmann et al. (2006) were employed. The intra-dyadic stress items addressed issues such as problems with the partner, overload with family responsibilities, not enough time for family, task sharing in the household, and feeling bothered by some of partner’s habits. The extra-dyadic stress items were chosen for their relevance to the COVID-19 pandemic period, and included concerns about events in the news, concerns about health in general, financial security, troublesome neighbors, too many things to do, concerns about job security, and dissatisfaction with work duties. Participants were asked if they had experienced each item during the lockdown period. If they had not, they were instructed to choose “0”; if they had, they rated the perceived severity of the item on a 3-point scale: 1 “somewhat stressful,” 2 “moderately stressful,” or 3 “extremely stressful.” Cronbach’s alpha for extra-dyadic and intra-dyadic stress were .71 and .74, respectively. Three summary scores each were generated for extra-dyadic and intra-dyadic stress: (1) frequency – a simple count of the number of items checked, which could range from 0 to 8; (2) cumulated severity – the sum of the 3-point severity ratings, which ranged from 0 to 24; and (3) intensity – cumulated severity divided by frequency, which ranged from 0 to 3. The latter scores, which provided an index of how intensely the average hassle was experienced regardless of the number (frequency) of hassles experienced, were used as the outcome measures for extra-dyadic and intra-dyadic stress. General mental health The MHI-18 (henceforth, MHI), a shortened version of the original 36-item Mental Health Inventory developed by Veit and Ware (1983), was used to assess the general mental health. It includes four subscales: anxiety (e.g., “Have you been a very nervous person?”), depression (e.g., “Have you been in low or very low spirits?”), behavioral/emotional control (e.g., “Have you been in firm control of your behavior, thoughts, emotions, feelings?”), and positive affect and emotional ties (e.g., “Has your daily life been full of things that were interesting to you?”; “Have you felt loved and wanted?”; “Have you felt cheerful, light-hearted?”). Participants were asked to indicate how often they had experienced various emotions during the lockdown period, using a 6-point scale ranging from 1 (all of the time) to 6 (none of the time). The MHI has four subscale scores and one total score. The subscale and total scores range from 0–100. Before computing the total MHI score, 8 of the items were converted to make negative and positive scores consistent. Mean MHI score was then computed based on all 18 items, yielding a range from 1 to 6. Next, total MHI total score (a transformation score) was computed as follows: [(Mean MHI - 1) * 100]/5. Thus, the range for total MHI score was from 0 (based on a mean MHI score of 1) to 100 (based on a mean MHI score of 6), with higher scores indicating better mental health. In the current study, Cronbach’s alpha for general mental health was .75. Sociodemographic variables The following sociodemographic variables were examined: gender, age, religion, level of education, marriage duration, number of children, employment, average family income before the pandemic, and COVID-19-related financial damage. Statistical analysis Data were analyzed using SPSS 26. First, descriptive statistics and bivariate correlations (see Table 2) were calculated for the study variables, including extra-dyadic stress, intra-dyadic stress, family cohesion, family flexibility, mental health, and the sociodemographic variables (age, education, marriage duration, number of children, average family income before the pandemic, and financial damage due to the pandemic). Next, to address the main study objective and test the proposed models, moderated mediation analysis was conducted in SPSS version 26 using the PROCESS macro (model 7; Hayes, 2018). The macro regressed the dependent variable, mental health, on the following variables: (a) the independent variable, extra-dyadic stress; (b) the mediating variable, intra-dyadic stress; and (c) any sociodemographic covariates that were significantly correlated with at least one of the study variables (these included age, marriage duration, number of children, family income before the pandemic, and financial damage due to the pandemic). The mediator was also regressed on the independent variable and on the covariates. The moderators were also regressed on the independent variable and on the covariates. This procedure was run for each of the moderator variables (cohesion and flexibility).Table 2. Means, Standard Deviations, and Bivariate Correlation Coefficients Between the Study Variables. M (SD) 1 2 3 4 5 6 7 8 9 10 11 1. Extra-dyadic stress 1.55 (.54) 2. Intra-dyadic stress 1.41 (.48) .58** 3. Cohesion 4.13 (.69) −.10* −.33 4. Flexibility 3.78 (.66) −.08 −.23 .79 5. Mental health 62.48 (11.24) −.35 −.45 .41 .33 6. Gender 0.71 (0.46) −.01 −.05 −.00 −.05 .00 7. Age 38.33 (9.66) −.07 −.05 −.16 −.10* .03 .18 8. Education 3.40 (1.40) −.07 −.01 −.01 .03 .05 −.05 .06 9. Marriage duration 14.73 (9.48) −.06 −.06 −.18 −.16 −.01 .08 .88 −.06 10. Number of children 2.82 (1.34) −.02 .02 −.15 −.15 .02 −.05 .62 −.14 .67 11. Average family income before the pandemic 3.44 (1.79) −.14 −.14 .05 .03 .14 −.13 .15 .45 .06 .01 12. Financial damage due to COVID-19 2.75 (1.65) .21 .21 −.13 −.14 −.29 .17 −.13 −.33 −.01 .06 −.37 Note. Mean scores could range from 0 for low stress to 3 for high stress for extra-dyadic and intra-dyadic stress, from 1 for low levels to 5 for high levels for family cohesion and flexibility, and from 0 for low levels to 100 for high levels for mental health. Gender: 0 = male (n = 141), 1 = female (n = 339). Age ranged from 18 to 86. Education: scores could range from 1 for low education to 5 for high education. Marriage duration could range from 1 to 54. Number of children could range from 1 to 10. Average family income before the pandemic: scores could range from 1 for very low income to 5 for very high income. Financial damage due to the pandemic: scores could range from 1 for no damage to 5 for great damage.p < .01; p < .001. To assess mediation and determine whether it was partial or complete, direct effects and indirect effects were estimated. Direct effects represent the direct pathways from an independent variable (e.g., extra-dyadic stress) to a dependent variable (mental health). Indirect effects represent the pathway from the independent variable (extra-dyadic stress) to the dependent variable (mental health) through a mediator (intra-dyadic stress). To determine the significance of the mediation effects, a bootstrapping technique was used (Preacher & Hayes, 2004), which resamples the existing dataset at least 5000 times to estimate the confidence intervals of the mediated effect. Results As a greater percentage of women participated in the study, t-tests were conducted to assess differences between women and men for all the study variables. As no significant differences were found, all the analyses were conducted on the entire sample. Bivariate correlations The results presented in Table 2 reveal a positive correlation between extra-dyadic stress and intra-dyadic stress, both of which were negatively correlated with mental health. In addition, a positive correlation between cohesion and flexibility, both of which were negatively correlated with intra-dyadic stress and positively correlated with mental health. Cohesion also negatively correlated with extra-dyadic stress. Average family income before the pandemic was negatively correlated with extra and intra-dyadic stress, and positively correlated with mental health. COVID-19-related financial damage was negatively correlated with cohesion, flexibility, mental health, and positively correlated with extra and intra-dyadic stress. Finally, age, marriage duration and number of children were negatively correlated with cohesion and flexibility. Overall, correlations between the study variables were as expected, enabling further examination of direct and indirect effects on mental health in the moderated mediation models. Moderated mediation models Figure 1 presents the standardized coefficients of each pathway of the two models, after controlling for age, marriage duration, number of children, family income before the pandemic, and COVID-19-related financial damage.Figure 1. Standardized Coefficients and Standard Error (SE) Values of the Moderated Mediation Models. Note. a1i = The effect of perceived extra-dyadic stress on intra-dyadic stress; a2i = The effect of family functioning (cohesion or flexibility) on intra-dyadic stress; a3i = The interaction effect of extra-dyadic and family functioning on intra-dyadic stress. p < .05; p < .01; p < .001. As shown in Table 3, the results demonstrated a significant direct effect of extra-dyadic stress on mental health (β = −.14, SE =.05, p = .005), supporting the first hypothesis. Furthermore, extra-dyadic stress demonstrated a significant effect on intra-dyadic stress (β = .55, SE = .04, p < .001; β = .56, SE = .04, p < .001, in Models A and B, respectively). In turn, intra-dyadic stress demonstrated significant direct effects on mental health (β = −.34, SE =.05, p < .001). Furthermore, the indirect effects, which are described below, were significant. In addition, after controlling for intra-dyadic stress, the direct effect of extra-dyadic stress on mental health was significant, suggesting partial mediation by intra-dyadic stress. These findings support the second hypotheses regarding the partial mediating effect of intra-dyadic stress on the relationship between extra-dyadic stress and mental health. Both extra- and intra-dyadic stress and the covariates accounted for 21.51% of the variance in mental health (F (7,473) = 18.52, p < .001).Table 3. The Moderated Mediation Effect of Extra-Dyadic Stress on Mental Health. Cohesion Flexibility Predictors Model 1 Model 2 Model 1 Model 2 β (95% C.I.) t β (95% C.I.) t β (95% C.I.) t β (95% C.I.) t Extra-dyadic stress .55 (.48, .62) 15.09 −.14 (−.24, −.04) −2.83 .56 (.49, .63) 15.12* −.14 (−.24, −.04) −2.83 Moderator −.25 (−.33, −.18) −6.86* −.18 (−.25, −.10) −4.69* Moderator X extra-dyadic stress −.08 (−.15, −.01) −2.23* −.08 (−.15, −.01) −2.31* Intra-dyadic stress −.34 (−.44, −.25) −6.88* −.34 (−.44, −.25) −6.88* Age .04 (−.12, .19) 0.47 .15 (−.03, .32) 0.11 .07 (−.09, .23) 0.86 .15 (−.03, .32) 1.61 Marriage duration −.16 (−.32, .00) −1.93 −.14 (−.33, .04) 0.13 −.18 (−.34, −.01) −2.12* −.14 (−.33, .04) −1.53 Number of children .07 (−.02, .17) 1.56 −.04 (−.15, .07) 0.48 .08 (−.02, .18) 1.64 −.04 (−.15, .07) −0.70 Average income before the pandemic −.05 (−.12, .03) −1.26 .07 (−.02, .16) 0.11 −.06 (−.14, .01) −1.62 .07 (−.02, .16) 1.61 Financial damage due to COVID-19 −.06 (−.14, .01) −1.69 .02 (−.06, .11) 0.59 −.08 (−.16, −.00) −2.03* .02 (−.06, .11) 0.54 Note. In Model 1, the dependent variable was intra-dyadic stress. In Model 2, mental health was the dependent variable. Family cohesion as moderator of the relationship between extra- and intra-dyadic stress (see Figure 1, Model A). A significant interaction was found between extra-dyadic stress and family cohesion (β = −.08, SE = .04, p = .027; R 2 change = .006, F change (1472) = 4.95, p = .027). As shown in Figure 2a, participants with lower levels of family cohesion (−1 SD) demonstrated a greater effect of extra-dyadic stress on intra-dyadic stress (β = .63, SE = 0.05, t = 11.60, p < .001), compared to participants with higher levels of family cohesion (+1 SD; β = .47, SE = .05, t = 9.58, p < .001). These findings support the third hypothesis regarding the moderating effect of family cohesion on the relationship between extra-dyadic stress and intra-dyadic stress. In addition, a significant effect of family cohesion on intra-dyadic stress was found (β = −.25, SE = .04, p < .001). The extra-dyadic stress, the moderator, and the covariates accounted for 41.20% of the variance in intra-dyadic stress (F (8,472) = 41.34, p < .001).Figure 2. (2a) The Association Between Extra-dyadic Stress and Intra-dyadic Stress at Low, Medium, and High Levels of Family Cohesion. (2b). The Association Between Extra-dyadic Stress and Intra-dyadic Stress at Low, Medium, and High Levels of Family Flexibility. Finally, the overall moderated mediation model was supported (index of moderated mediation = 0.028; SE = 0.016; 95% CI: 0.001, 0.061). Results indicated that intra-dyadic stress mediated the effect of extra-dyadic stress on mental health, and family cohesion weakened the mediating effect of intra-dyadic stress. Specifically, the indirect effect of extra-dyadic stress through intra-dyadic stress on mental health was significant and the strongest for lower levels of cohesion (β = −.22, SE = 0.04; 95% CI: −.30, −.14), compared to medium levels of cohesion (β = −.19, SE = 0.03; 95% CI: −.25, −.12), and higher levels of cohesion (β = −.16, SE = 0.03; 95% CI: −.22, −.10). Family flexibility as moderator of the relationship between extra- and intra-dyadic stress (see Figure 1, Model B). A significant interaction effect was found between extra-dyadic stress to family flexibility (β = −.08, SE = .04, p = .021; R 2 change = .007, F change (1472) = 5.34, p = .021). As shown in Figure 2b, participants with lower levels of family flexibility (−1 SD) demonstrated a greater effect of extra-dyadic stress on intra-dyadic stress (β = .64, SE = .05, t = 11.88, p < .001), compared to participants with higher levels of family flexibility (+1 SD; β = .48, SE = .05, t = 9.78, p < .001). These findings support the third hypothesis regarding the moderating effect of family flexibility on the relationship between extra-dyadic stress and intra-dyadic stress. In addition, a significant effect of family flexibility on intra-dyadic stress (β = −.18, SE = .04, p < .001). The extra-dyadic stress, the moderator, and the covariates accounted for 37.94% of the variance in intra-dyadic stress (F(8,472) = 36.22, p < .001). Finally, the overall moderated moderation model was supported (index of moderated mediation = 0.029; SE = 0.015; 95% CI: 0.001, 0.060). Results indicated that intra-dyadic stress mediated the effect of extra-dyadic stress n mental health, and family flexibility weakened the mediating effect of intra-dyadic stress. Specifically, the indirect effect of extra-dyadic stress through intra-dyadic stress on mental health was significant and strongest for lower levels of flexibility (β = −.22, SE = 0.04; 95% CI: −.31, −.14), compared to medium levels of flexibility (β = −.19, SE = 0.03; 95% CI: −.26, −.13), and higher levels of flexibility (β = −.16, SE = 0.03; 95% CI: −.23, −.11). Discussion Two moderated mediation models based on the systemic-transactional model (STM; Bodenmann, 1995; 1997) were used to examine the relationship between stress from daily hassles and mental health among married individuals during the early stages of the COVID-19 pandemic. The results showed that alongside a direct relationship between the extra-dyadic stress and mental health, intra-dyadic stress played a mediating role and family functioning played a moderating role. Specifically, extra-dyadic-stress was positively associated with intra-dyadic stress, which in turn was negatively associated with mental health, indicating partial mediation. Furthermore, a significant interaction effect was found between extra-dyadic stress and both family cohesion and flexibility, indicating that these family functioning variables moderate the association between extra-dyadic-stress intra-dyadic stress. Participants with lower levels of family cohesion and flexibility demonstrated a greater effect of extra-dyadic stress on intra-dyadic stress, compared to participants with higher levels of family cohesion and flexibility. The overall moderated mediation model was supported, as intra-dyadic stress mediated the effect of extra-dyadic stress on mental health, and family cohesion and flexibility weakened the mediating effect of intra-dyadic stress. The results support the distinction between stressors that are external to and internal to the intimate dyad (see Bodenmann, 2000; 2005; Bodenmann et al., 2007; Neff & Karney, 2004) and suggest that extra-dyadic stress influences mental health both directly and indirectly through intra-dyadic stress (Bodenmann et al., 2016; Falconier et al., 2015; Neff & Karney, 2017). Family functioning can therefore be considered a protective factor that provides a buffer from the adverse effects of extra-dyadic stress on intra-dyadic stress. The COVID-19 pandemic brought on a range of stressors, among them environmental stressors, such as increased workloads and financial difficulties (Pietromonaco & Overall, 2021), disrupted family routines and responsibilities (Goldberg et al., 2021), and increased burden of unpaid work and childcare (Craig & Churchill, 2020). These stressors were often expressed in additional daily hassles, with corresponding decreases in mental health (Goldberg et al., 2021; Gray et al., 2020; Reizer et al., 2020). The current findings contribute to our understanding of the mechanisms through which pandemic stressors disrupted mental health. The relationship between extra-dyadic stress and mental health The results support previous findings indicating that stress from daily hassles plays an important role in understanding the mental health of married individuals. Several researchers have shown that high levels of daily stress are associated with greater anxiety and depression and lower mental health (D’Angelo & Wierzbicki, 2003; Parrish et al., 2011; Schönfeld et al., 2019; Serido et al., 2004). Specifically regarding extra-dyadic stress from daily hassles, previous work shows a direct negative impact on individual mental health (Bodenmann, 1997). This claim has been supported in several studies with a range of outcome measures (Falconier et al., 2015; Serido et al., 2004; Ledermann et al., 2010). The mediating role of intra-dyadic stress The present study also examined the mediating role of intra-dyadic stress in the relationship between extra-dyadic stress and mental health. As expected, extra-dyadic-stress was positively associated with intra-dyadic stress, which in turn was negatively associated with mental health. The first path, indicating that extra-dyadic stress was positively related to intra-dyadic stress, supports Bodenmann’s theory and previous studies showing that during periods of relatively high external stress, couples are more likely to report struggling with serious problems within the relationship, such as spending less time connecting with one another, lacking intimacy, feeling neglected by their partner, and increased differences in attitude (Neff & Karney, 2017). When couples face significant external stressors, as they did during the pandemic, critical time together often becomes limited and characterized by greater disconnection (Repetti et al., 2009). The second path of the mediation model indicated that intra-dyadic stress was negatively related to mental health. This was also consistent with previous studies, which found that intra-dyadic stress is related to depression (Falconier et al., 2015) and that marital tension and negative interactions are associated with symptoms of depression (Whisman & Uebelacker, 2009) and anxiety (Addis & Bernard, 2002; Chambless et al., 2001). Overall, this study joins previous empirical work supporting the mediating role of intra-dyadic stress in the association between extra-dyadic stress from daily hassles and psychological well-being (Falconier et al., 2015). The novel question examined here was whether family cohesion and flexibility could affect mental health by altering the relationship between extra-dyadic and intra-dyadic stress. The moderating role of family functioning The results further revealed that family cohesion and flexibility moderate the path between extra-dyadic and intra-dyadic stress. As expected, among participants who reported higher cohesion and flexibility, the association between extra-dyadic and intra-dyadic stress was weaker. These novel results support the assumption that when extra-dyadic stress does not go hand in hand with intra-dyadic stress, better outcomes can be expected. In the STM, Bodenmann et al. (2016) used the term dyadic coping in reference to the mechanisms that prevent extra-dyadic stress from increasing intra-dyadic stress, specifically noting provision of support and joint efforts to deal with common stressors. The current study raises the possibility that both family cohesion and family flexibility contribute significantly to such coping, thereby preventing extra-dyadic stress from daily hassles from spilling over into the relationship. This, in turn, can reduce negative effects on mental health. Limitations The findings and conclusions of this study should be considered in the context of several limitations. First, the sampling method employed, in which participants had access to and were users of social media, and chose to complete an online survey, could have resulted in a selection bias. This might limit the generalizability of the results, although a large sample of participants with a broad sociodemographic range was included. Second, the study relied solely on self-report questionnaires, which are subjective by definition and affected by various biases. Third, the study was cross-sectional, making it impossible to determine causative relationships between the variables. Future studies are needed to evaluate whether the reported associations continued to be maintained longitudinally following the early stages of the pandemic, given that all the study variables could potentially be affected by increasing mortality rates, economic burdens, and other long-term effects of COVID-19. In the context of generalizability, it should be noted that while the majority of previous work on ties between family functioning and mental health were conducted in Western societies, participants in the current study were from the Arab society in Israel. In general, this is a collectivistic culture (Haj-Yahia, 2019) that tends to differ essentially from Western societies with respect to values and norms related to all the variables addressed in this study. Though it is beyond the scope of the current work to assess the manner in which these values and norms might have affected the results, it is certainly possible that such effects would be found in a broader, cross-cultural comparison. Further work should address such cross-cultural differences, as well as differences resulting from other sociodemographic or geography-based variables, for example the extent of damage incurred and of aid offered during the COVID-19 pandemic. Conclusions and implications This study increases our understanding of variables related to stress processes and mental health among married individuals during the COVID-19 pandemic. In accordance with the STM (Bodenmann et al., 2016), intra-dyadic stress was shown to play a critical role in mediating the effects of extra-dyadic stress on mental health. Furthermore, family functioning was shown to moderate the relationship between extra-dyadic and intra-dyadic stress. These findings suggest that married individuals with cohesive and flexible family environments are protected from the negative effects of external stressors on their relationship, and in turn on their mental health. The current work has implications for planning couple interventions during the pandemic and in general, with the dual goals of improving marital satisfaction and supporting the mental health of the partners. If stress from daily hassles is likely to decrease mental health directly and also indirectly by raising intra-dyadic stress, then couples’ therapists should routinely assess both the presence of major external stressors and their effects on relationship stress. Moreover, reducing daily hassles or coping with them effectively so that they do not spill into the couple’s relationship or deteriorate partners’ individual well-being may become a key goal of therapy and guide therapists towards intervention methods focused on enhancing communication and joint coping. Furthermore, the findings suggest that intervention efforts should be focused on encouraging cohesive and flexible environments, as a means of reducing the effect of external stress on relationship stress. To promote cohesion, interventions should urge families to increase interaction and communication between members and to resolve conflicts constructively. Flexibility, meanwhile, can be increased by creating viable mechanisms to adjust family rules and roles in response to environmental changes. ORCID iD Niveen M. Hassan-Abbas https://orcid.org/0000-0001-5626-4679 Ethical approval: The author confirms being the sole contributor of this study and has approved it for publication. The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article. ==== Refs References Abu-Baker K. (2003). Career women or working women? Change versus stability for young Palestinian women in Israel. Journal of Israeli History, 21 (1–2 ), 85–109. 10.1080/13531040212331295872 Addis J. Bernard M. E. (2002). Marital adjustment and irrational beliefs. Journal of Rational Emotive & Cognitive Behavior Therapy, 20 (1 ), 3–13. 10.1023/A:1015199803099 Al-Krenawi A. Graham J. R. (2005). Marital therapy for Arab muslim Palestinian couples in the context of reacculturation. The Family Journal, 13 (3 ), 300–310. 10.1177/1066480704273640 Azaiza F. (2008a). The perception and utilisation of social support in times of cultural change: The case of Arabs in Israel. International Journal of Social Welfare, 17 (3 ), 198-203. 10.1111/j.1468-2397.2008.00542.x. Azaiza F. (2008b). Appropriateness of the helpline as a mode of service delivery in minority communities: The case of the Arab population in Israel. Journal of Human Behavior in the Social Environment, 18 (4 ), 463-476. 10.1080/10911350802486908. Barzilay R. Moore T. M. Greenberg D. M. DiDomenico G. E. Brown L. A. White L. K. Gur R. C. Gur R. E. (2020). Resilience, COVID-19-related stress, anxiety and depression during the pandemic in a large population enriched for healthcare providers. Translational Psychiatry, 10 (1 ), 291. 10.1038/s41398-020-00982-4 32820171 Berryhill M. B. Harless C. Kean P. (2018). College student cohesive-flexible family functioning and mental health: Examining gender differences and the mediation effects of positive family communication and self-compassion. The Family Journal, 26 (4 ), 422–432. 10.1177/1066480718807411 Bodenmann G. (1995). A systemic-transactional conceptualization of stress and coping in couples. Swiss Journal of Psychology/Schweizerische Zeitschrift Für Psychologie/Revue Suisse de Psychologie, 54 (1 ), 34–49. Bodenmann G. (1997). Dyadic coping - a systemic-transactional view of stress and coping among couples: Theory and empirical findings. European Review of Applied Psychology, 47 , 137–140. Bodenmann G. (2005). Dyadic coping and its significance for marital functioning. In Revenson T. Kayser K. Bodenmann G. (Eds), Couples coping with stress: Emerging perspectives on dyadic coping (pp. 33–50). American Psychological Association. Bodenmann G. Ledermann T. Blattner D. Galluzzo C. (2006). Associations among everyday stress, critical life events, and sexual problems. The Journal of Nervous and Mental Disease, 194 (7 ), 494–501. 10.1097/01.nmd.0000228504.15569.b6 16840845 Bodenmann G. Ledermann T. Bradbury T. (2007). Stress, sex, and satisfaction in marriage. Personal Relationships, 14 (4 ), 551–569. 10.1111/j.1475-6811.2007.00171.x Bodenmann G. Randall A. K. Falconier M. K. (2016). Coping in couples: The systemic-transactional model. In Falconier M. K. Randall A. K. Bodenmann G. (Eds), Couples coping with stress: A cross-cultural perspective (pp. 5–12). Routledge. Chambless D. L. Bryan A. D. Aiken L. S. Steketee G. Hooley J. M. (2001). Predicting expressed emotion: A study with families of obsessive–compulsive and agoraphobic outpatients. Journal of Family Psychology, 15 (2 ), 296–304. 10.1037/0893-3200.15.2.225 Chang W. C. Neo A. H. C. Fung D. (2015). In search of family resilience. Psychology, 06 (13 ), 1594–1607. 10.4236/psych.2015.613157 Craig L. Churchill B. (2020). Dual-earner parent couples’ work and care during COVID‐19. Gender, Work & Organization, 28 (S1 ), 66–79. 10.1111/gwao.12497 32837023 D’Angelo B. Wierzbicki M. (2003). Relations of daily hassles with both anxious and depressed mood in students. Psychological Reports, 92 (2 ), 416–418. 10.2466/pr0.2003.92.2.416 12785621 Falconier M. K. Nussbeck F. Bodenmann G. Schneider H. Bradbury T. (2015). Stress from daily hassles in couples: Its effects on intradyadic stress, relationship satisfaction, and physical and psychological well-being. Journal of Marital and Family Therapy, 41 (2 ), 221–235. 10.1111/jmft.12073 24807831 Folkman S. Lazarus R. S. (1980). An analysis of coping in a middle-aged community sample. Journal of Health and Social Behavior, 21 (3 ), 219–239. 10.2307/2136617 7410799 Forte G. Favieri F. Tambelli R. Casagrande M. (2020). COVID-19 pandemic in the Italian population: Validation of a post-traumatic stress disorder questionnaire and prevalence of PTSD symptomatology. International Journal of Environmental Research and Public Health, 17 (11 ), 4151. 10.3390/ijerph17114151 32532077 García-Huidobro D. Puschel K. Soto G. (2012). Family functioning style and health: Opportunities for health prevention in primary care. British Journal of General Practice, 62 (596 ), 198–203. 10.3399/bjgp12X630098 Goldberg A. E. McCormick N. Virginia H. (2021). Parenting in a pandemic: Work–family arrangements, well-being, and intimate relationships among adoptive parents. Family Relations, 70 (1 ), 7–25. 10.1111/fare.12528 Gray N. S. O’ConnorKnowles C.J. Pink J. Simkiss N. J. Williams S. D. Snowden R. J. (2020). The influence of the COVID-19 pandemic on mental well-being and psychological distress: Impact upon a single country. Frontiers in Psychiatry, 11 , 594115. 10.3389/fpsyt.2020.594115 33262714 Haj-Yahia M. M (2019). The Palestinian family in Israel. In Haj-Yahia M. M. Nakash O. Levav I. (Eds), Mental health and Palestinian citizens in Israel (pp. 97–120). Indiana University Press. Harris C. A. Zakowski S. G. (2003). Comparisons of distress in adolescents of cancer patients and controls. Psycho-oncology, 12 (2 ), 173–182. 10.1002/pon.631 12619149 Hayes A. F. (2018). Introduction to mediation, moderation, and conditional process analysis: A regression-based approach. Guilford Press. Hennon C. B. Peterson G. Hildenbrand B. Wilson S. (2008). Parental stress amongst migrant and immigrant populations. Pesquisas e Práticas Psicossociais, 2 (2 ), 242–257. Hu N. Li Y. He S. S. Wang L. L. Wei Y. Y. Yin L. Chen J. X. (2020). Impact of the family environment on the emotional state of medical staff during the COVID-19 outbreak: The mediating effect of self-efficacy. Frontiers in Psychology, 11 , 576515. 10.3389/fpsyg.2020.576515 33162916 Israel Central Bureau of Statistics (2019). Social survey. www.cbs.gov.il/en/subjects/Pages/Social-Survey.aspx Kanner A. D. Coyne J. C. Schaefer C. Lazarus R. S. (1981). Comparison of two modes of stress measurement: Daily hassles and uplifts versus major life events. Journal of Behavioral Medicine, 4 (1 ), 1–39. 10.1007/BF00844845 7288876 Kimhi S. Marciano H. Eshel Y. Adini B. (2020). Recovery from the COVID-19 pandemic: Distress and resilience. International Journal of Disaster Risk Reduction, 50 , 101843. 10.1016/j.ijdrr.2020.101843 32953439 Koutra K. Simos P. Triliva S. Lionis C. Vgontzas A. N. (2016). Linking family cohesion and flexibility with expressed emotion, family burden and psychological distress in caregivers of patients with psychosis: A path analytic model. Psychiatry Research, 240 , 66–75. 10.1016/j.psychres.2016.04.017 27085666 Lazarus R. S. Folkman S. (1984). Stress, appraisal, and coping. Springer. Ledermann T. Bodenmann G. Rudaz M. Bradbury T. N. (2010). Stress, communication, and marital quality. Family Relations, 59 (2 ), 195–206. 10.1111/j.1741-3729.2010.00595.x Mohindra R. Suri V. Bhalla A. Singh S. M. (2020). Issues relevant to mental health promotion in frontline health care providers managing quarantined/isolated COVID-19 patients. Asian Journal of Psychiatry, 51 , 102084. 10.1016/j.ajp.2020.102084 32289728 Neff L. A Karney B. R. (2004). How does context affect intimate relationships? Linking external stress and cognitive processes within marriage. Personality & Social Psychology Bulletin, 30 (2 ), 134–148. 10.1177/0146167203255984 15030629 Neff L. A. Karney B. R. (2017). Acknowledging the elephant in the room: How stressful environmental contexts shape relationship dynamics. Current Opinion in Psychology, 13 , 107–110. 10.1016/j.copsyc.2016.05.013 27766285 Neo A. H. C. Chang W. C. Fung D. S. S. (2016). An actor-partner interdependence model on family resilience and subjective wellbeing. Psychology, 07 (06 ), 889–900. 10.4236/psych.2016.76091 Olson D. H. (1991). Commentary: Three-Dimensional (3-D) circumplex model and revised scoring of FACES III. Family Process, 30 (1 ), 74–79. 10.1111/j.1545-5300.1991.00074.x 2044752 Olson D. H. (1993). Circumplex model of marital and family systems: Assessing family functioning in normative family processes. Guilford Press. Olson D. H. (2000). Circumplex model of marital and family systems. Journal of Family Therapy, 22 (2 ), 144–167. 10.1111/1467-6427.00144 Olson D. H. Gorall D. M. (2006). Faces IV and the circumplex model. Life Innovations, Inc. Olson D. H. Portner J. Lavee Y. (1985). Faces III”: Family adaptability & cohesion evaluation scales Family social science. University of Minnesota. Olson D. H. Sprenkle D. H. Russell C. S. (1979). Circumplex model of marital and family systems: I. Cohesion and adaptability dimensions, family types, and clinical applications. Family Process, 18 (1 ), 3–28. 10.1111/j.1545-5300.1979.00003.x 437067 Parrish B. P. Cohen L. H. Laijrenceaij J. P. (2011). Prospective relationship between negative affective reactivity to daily stress and depressive symptoms. Journal of Social and Clinical Psychology, 30 (3 ), 270–296. 10.1521/jscp.2011.30.3.270 Perrin P. B. Stevens L. F. Sutter M. Hubbard R. Díaz Sosa D. M. Espinosa Jove I. G. Arango-Lasprilla J. C. (2013). Exploring the connections between traumatic brain injury caregiver mental health and family dynamics in Mexico City, Mexico. PM&R, 5 (10 ), 839–849. 10.1016/j.pmrj.2013.05.018 23735587 Peterson G. (2017). Conceptualizing parental stress with family stress theory. In Price C. A. Bush K. R. Price S. J. (Eds), Families and change: Coping with stressful events and transitions (pp. 53–78). Sage Publications. Pietromonaco P. R. Overall N. C. (2021). Applying relationship science to evaluate how the COVID-19 pandemic may impact couples’ relationships. American Psychologist, 76 (3 ), 438–450. 10.1037/amp0000714 32700937 Polizzi C. Lynn S. J. Perry A. (2020). Stress and coping in the time of COVID-19: Pathways to resilience and recovery. Clinical Neuropsychiatry, 17 (2 ), 59–62. 10.36131/CN20200204 34908968 Pollock E. D. Kazman J. B. Deuster P. (2015). Family functioning and stress in african American families: A strength-based approach. Journal of Black Psychology, 41 (2 ), 144–169. 10.1177/0095798413520451 Preacher K. J. Hayes A. F. (2004). SPSS and SAS procedures for estimating indirect effects in simple mediation models. Behavior Research Methods, Instruments, & Computers, 36 (4 ), 717–731. 10.3758/BF03206553 Prime H. Wade M. Browne D. T. (2020). Risk and resilience in family well-being during the COVID-19 pandemic. American Psychologist, 75 (5 ), 631–643. 10.1037/amp0000660 32437181 Randall A. K. Bodenmann G. (2009). The role of stress on close relationships and marital satisfaction. Clinical Psychological Review, 29 (2 ), 105–115. 10.1016/j.cpr.2008.10.004 Reizer A. Koslowsky M. Geffen L. (2020). Living in fear: The relationship between fear of COVID-19, distress, health, and marital satisfaction among Israeli women. Health Care for Women International, 41 (11–12 ), 1273–1293. 10.1080/07399332.2020.1829626 33084536 Repetti R. Wang S. Saxbe D. (2009). Bringing it all back home: How outside stressors shape families’ everyday lives. Current Directions in Psychological Science, 18 (2 ), 106–111. 10.1111/j.1467-8721.2009.01618.x Salin M. Kaittila A. Hakovirta M. Anttila M. (2020). Family coping strategies during Finland’s COVID-19 lockdown. Sustainability, 12 (21 ), 1–13. 10.3390/su12219133 35136666 Sander A. M. Caroselli J. S. High W. M. Becker C. Neese L. Scheibel R. (2002). Relationship of family functioning to progress in a post-acute rehabilitation programme following traumatic brain injury. Brain Injury, 16 (8 ), 649–657. 10.1080/02699050210128889 12182162 Schönfeld P. Brailovskaia J. Zhang X. C. Margraf J. (2019). Self-efficacy as a mechanism linking daily stress to mental health in students: A three-wave cross-lagged study. Psychological Reports, 122 (6 ), 2074–2095. 10.1177/0033294118787496 30235979 Serido J. Almeida D. M. Wethington E. (2004). Chronic stressors and daily hassles: Unique and interactive relationships with psychological distress. Journal of Health and Social Behavior, 45 (1 ), 17–33. 10.1177/002214650404500102 15179905 Sheidow A. J. Henry D. B. Tolan P. H. Strachan M. K. (2014). The role of stress exposure and family functioning in internalizing outcomes of urban families. Journal of Child and Family Studies, 23 (8 ), 1351–1365. 10.1007/s10826-013-9793-3 25601821 Stevens L. F. Perrin P. B. Hubbard R. Díaz Sosa D. M. Espinosa Jove I. G. Arango-Lasprilla J. C. (2013). Using multiple views of family dynamics to predict the mental health of individuals with TBI and their caregivers in Mexico. Neurorehabilitation, 33 (2 ), 273–283. 10.3233/NRE-130955 23949065 Story L. B. Repetti R. (2006). Daily occupational stressors and marital behavior. Journal of Family Psychology, 20 (4 ), 690–700. 10.1037/0893-3200.20.4.690 17176205 Veit C. T. Ware J. E. (1983). The structure of psychological distress and well-being in general populations. Journal of Consulting and Clinical PsychologyJournal of Consulting and Clinical Psychology, 51 (5 ), 730–742. 10.1037/0022-006X.51.5.730 6630688 Wang Y. Haslam M. Yu M. Ding J. Lu Q. Pan F. (2015). Family functioning, marital quality and social support in Chinese patients with epilepsy. Health and Quality of Life Outcomes, 13 (1 ), 10. 10.1186/s12955-015-0208-6 25627321 Whisman M. A. Uebelacker L. A. (2009). Prospective associations between marital discord and depressive symptoms in middle-aged and older adults. Psychology and Aging, 24 (1 ), 184–189. 10.1037/a0014759 19290750 Ye B. Hu J. Im H. Liu M. Wang X. Yang Q. (2022). Family cohesion and sleep disturbances during COVID-19: The mediating roles of security and stress. International Journal of Mental Health and Addiction. Advance online publication 10.1007/s11469-022-00753-w
PMC009xxxxxx/PMC9638199.txt	==== Front J Behav Med J Behav Med Journal of Behavioral Medicine 0160-7715 1573-3521 Springer US New York 36334169 374 10.1007/s10865-022-00374-7 Article Associations between social COVID-19 exposure and psychological functioning http://orcid.org/0000-0002-8986-992X Lewicka Malwina [email protected] 1 http://orcid.org/0000-0001-8377-4666 Hamilton Jada G. [email protected] 1 http://orcid.org/0000-0001-7402-0133 Waters Erika A. [email protected] 2 http://orcid.org/0000-0002-0147-8378 Orom Heather [email protected] 3 http://orcid.org/0000-0002-4745-3707 Schofield Elizabeth [email protected] 1 http://orcid.org/0000-0002-1299-8416 Kiviniemi Marc T. [email protected] 4 http://orcid.org/0000-0002-5567-9618 Kanetsky Peter A. [email protected] 5 http://orcid.org/0000-0002-3492-9331 Hay Jennifer L. [email protected] 1 1 grid.51462.34 0000 0001 2171 9952 Department of Psychiatry and Behavioral Sciences, Memorial Sloan Kettering Cancer Center, 641 Lexington Ave, New York, NY 10022 USA 2 grid.4367.6 0000 0001 2355 7002 Division of Public Health Sciences, Washington University in St. Louis, 4590 Children’s Place, Suite 9600, St. Louis, MO 63110 USA 3 grid.273335.3 0000 0004 1936 9887 Department of Community Health and Health Behavior, University at Buffalo, 304 Kimball, Buffalo, NY 14214 USA 4 grid.266539.d 0000 0004 1936 8438 Department of Health, Behavior and Society, University of Kentucky, 1000 S. Limestone, Lexington, KY 40536 USA 5 grid.468198.a 0000 0000 9891 5233 Department of Cancer Epidemiology, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612 USA 5 11 2022 2023 46 3 472482 17 6 2022 18 10 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. The negative consequences of the COVID-19 pandemic on mental health have been widely reported, but less is known about how the impact of COVID-19 on others in one’s social circle shapes these high distress levels. This study examines associations between social COVID-19 exposure—knowing someone who had a COVID-19 infection—and psychological functioning, as well as whether socio-demographic factors moderate these relationships. In June 2020, respondents (N = 343) from clinics in Tampa, Florida, U.S.A. reported whether they had social COVID-19 exposure, anxiety, depression, and stress, and other COVID-19-related concerns. Social COVID-19 exposure was associated with increased anxiety, stress, and concerns about a family member getting sick, and concerns about drinking and substance use. Several associations between exposure and psychological functioning were stronger in women, younger people, and people with lower income, implying these groups face elevated psychological risks due to the pandemic, and should be prioritized in mental health recovery efforts. Keywords COVID-19 Social factors Psychological functioning COVID-19 concerns Exploratory factor analysis (EFA) Moderation analyses Participant Research, Interventions & Measurement Core at the H. Lee Moffitt Cancer Center & Research InstituteP30-CA076292 Kanetsky Peter A. http://dx.doi.org/10.13039/100000048 American Cancer Society RSG-14-162-01-CPHPS Kanetsky Peter A. National Cancer Institute Ponce Health Sciences University-Moffitt Cancer Center PartnershipU54 CA163068 Kanetsky Peter A. http://dx.doi.org/10.13039/100007316 Division of Cancer Prevention, National Cancer Institute P30 CA008748 T32CA00946 Lewicka Malwina issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction The COVID-19 pandemic is an unprecedented public health challenge that has had devastating consequences for the United States, which reported the highest number of cases and COVID-19-related deaths in the world (World Health Organization [WHO], 2022). As COVID-19 spread throughout the nation, it not only increased morbidity and mortality rates, but also caused significant psychological distress, including steep increases in stress, anxiety, and depression (Panchal, 2021). For example, a representative survey conducted among adults aged ≥ 18 years across the United States in June 20,200 showed that 41% of respondents reported at least one adverse mental health outcome, including symptoms of anxiety disorder or depressive disorder (31%), symptoms of a trauma-and stressor-related disorder attributable to the pandemic (27%; Czeisler et al., 2020). This translates into sharp deterioration in mental health during the pandemic compared to pre-COVID-19. For example, in 2020 the rates of anxiety and depression among the U.S. public increased by more than three and four times respectively, relative to 2019 (Czeisler et al., 2020). According to the biopsychosocial model, physical and mental health are a produced by the dynamic interplay of social, psychological, and biological factors (Engel, 1977). In this study, we applied the biopsychosocial model to the study of mental health during the early months of the COVID-19 pandemic by asking how one key social factor—knowing someone who had COVID-19, or “social COVID-19 exposure”—may have shaped high distress levels in the U.S. population in the context of a novel and highly-contagious pathogen with unknown long-term health consequences. Because biopsychosocial formulations are beneficial for informing mitigative efforts targeting exposure and vulnerability to COVID-19 as well as developing and improving acute and long-term interventions (Kop, 2021), a study integrating biological, social, and psychological factors is critically important to the understanding of health risks and disease outcomes of the COVID-19 pandemic. There are important insights to be gained about the dynamics between social exposure and psychological functioning during the early stage of a novel infectious outbreak. Specifically, because early in the pandemic there was great uncertainty about the epidemiology, transmission, and consequences of infection by the SARS-CoV-2 virus, the social impacts of COVID-19 may have been more severe in the early months of the pandemic (rather than in subsequent months when certainty about scientific knowledge was higher; Otu et al., 2020). Being socially connected is generally linked to psychological benefits (Holt-Lunstad et al., 2017). However, in the context of an infectious disease pandemic where others can be the source of infection, the health status of one’s social circle may impact psychological outcomes. Specifically, when members of individuals’ social circles develop infections, those within those circles may experience more distress than when the infections occur outside those circles. There are two putative mechanisms implicated. First, knowing others who have been infected with COVID-19 could increase one’s own perceived vulnerability to infection—either directly as a source of personal viral exposure or indirectly by serving as easily accessible reminders of the disease’s presence (Butter et al., 2021; Pachur et al., 2012; Schulze et al., 2021; Tversky & Kahneman, 1973, 1974;)—and lead to psychological distress. Second, worrying about the health and well-being of known others infected with the virus could more directly lead to psychological distress (Adams et al., 2021; Lightfoot et al., 2021). Some segments of the population, including women and younger adults (Dragioti et al., 2021), those with less income (Hall et al., 2021), parents and children (Czeisler et al., 2021), and communities of color (Panchal, 2021) experienced more adverse psychological consequences due to the COVID-19 pandemic. Thus, these groups may be particularly susceptible to any negative psychological consequences of interpersonal factors such as social COVID-19 exposure. Investigating whether and how potential effects of social COVID-19 exposure on distress might vary by these socio-demographic factors could help identify individuals particularly likely to experience psychological adversities related to COVID-19 and future infectious disease outbreaks. Consistent with the biopsychosocial model, we investigated how social COVID-19 exposure may be associated with psychological functioning, and whether select socio-demographic characteristics might moderate these associations. Accordingly, the first aim of this study was to examine whether social COVID-19 exposure is associated with our primary psychological outcomes: anxiety, depression, stress, and COVID-19 specific concerns, which included items describing areas of life vulnerable to potential complications due to the pandemic (e.g., personal and family health, work, finances). We hypothesized that those with social COVID-19 exposure would have more negative psychological outcomes compared to people without social exposure. The second aim was to explore whether select socio-demographic variables moderate the relationships between social COVID-19 exposure and our primary psychological outcomes. Given the exploratory nature of this aim, no specific hypotheses were tested. Method Survey data were collected between June 8 and June 27, 2020 from participants who were enrolled onto one of two skin cancer prevention intervention studies, one conducted among non-Hispanic White participants and one conducted among Hispanic participants. Both studies predominately recruited participants from two non-specialty, academic clinic settings in Tampa, Florida, U.S.A. Details of these studies have been published elsewhere (Lacson et al., 2021, 2022). Trial participants who previously (i) consented to be re-contacted for future studies, (ii) provided an email address, (iii) completed the baseline study questionnaire for the intervention trial, (iv) indicated English as a language preference, and were (iv) less than 89 years of age and (v) not under active trial follow up were sent an email inviting them to participate in a COVID-19 research study. The email message contained an active link to a secured Research Electronic Data Capture (REDCap) application hosted at Moffitt Cancer Center that housed the COVID-19 survey. At the time of the emails, the trial conducted among non-Hispanic White participants was closed to follow up; the trial among Hispanic participants was closed to accrual, but under active follow up. A total of 1247 emails were sent, but 33 bounced back to the sender (3%). Of the 1214 emails (1015 to non-Hispanic White participants, 199 to Hispanic participants) that were received, a total of 343 (28%) participants completed the survey. Completion rates among non-Hispanic white (29%) and Hispanic (23%) participants were similar. This study was deemed exempt from human subjects consideration by Advarraa (provider of institutional review board (IRB) services) and an alteration of HIPAA authorization per 45 CFR 164.512(i)(ii) was granted; informed consent was not obtained from participants completing the survey. Socio-demographic information reported by participants included age, sex, ethnicity, race, education, income, and household size and composition. Measures Social COVID-19 exposure Social COVID-19 exposure was measured using the question “Has someone you know had or think they’ve had COVID-19?” The exposure group included participants who responded that they knew someone who was tested and confirmed to have COVID-19 and/or had symptoms but was not tested. The no-exposure group was comprised of those who reported not knowing anyone with COVID-19 or who responded “I don’t know” to the question. COVID-19 concerns A range of COVID-19 concerns were assessed using 23 statements generated by the study team describing potential complications associated with the pandemic. Participants indicated their level of concern using a 3-point response scale ranging from 1 (not concerned) to 3 (very concerned). Participants were also provided with a “not applicable” response option for each statement. We grouped the “not applicable” responses with “not concerned,” inferring that if a person saw a given complication as not relevant to them, then it likely posed no concerns for them. The items addressed included personal and family health, government response to the pandemic, work, finances, and lifestyle challenges. Anxiety and depression Anxiety and depression were measured using the Patient Health Questionnaire-4 (Kroenke et al., 2009) a 4-item, valid, reliable (α = 0.88), ultra-brief screener assessing depression (2 items) and anxiety (2 items) on a 4-point scale from 0 (not at all) to 3 (nearly every day). The total scores for anxiety and depression were obtained by summing the respective item responses, with the possible score range for either construct being 0 to 6. Higher scores denote more anxiety or depression, and scores of 3 or more on either subscale indicate clinically significant levels (Kroenke et al., 2009). Stress Stress was measured using the Perceived Stress Scale-4 (Cohen et al., 1983), a 4-item scale with adequate validity and reliability (α = 0.70) assessing perceived stress on a 5-point scale from 0 (never) to 4 (often). The stress score was computed as the sum of the 4 items; higher scores denote more stress. There is no cut-off score established for PSS-4 to determine clinically significant levels of stress. Statistical approach We examined the underlying structure of COVID-19 concerns using exploratory factor analysis (EFA). Given that the data were approximately normally distributed, we used maximum likelihood as the extraction method (Osborne, 2014) with oblique rotation (promax). One item, “Concerns about drinking more or using substances more,” did not meet the communality threshold of 0.2, and was subsequently removed from analyses. Three items (“Getting sick myself,” “A family member getting sick,” “Not being able to get tested if I develop symptoms”) cross-loaded on several factors and were included in subsequent analyses as individual items. The EFA with the remaining 19 items was re-run to determine the final factor structure. Factorability of the data was established using the Kaiser–Meyer–Olkin (KMO = 0.83) measure of sampling adequacy and deemed “meritorious” (Kaiser & Rice, 1974). Bartlett’s test of sphericity was statistically significant (χ2 (171) = 3711.59, p < 0.001). Items comprising each factor were averaged, and each factor was examined as an outcome in the subsequent analyses (see Table 2 for the EFA analyses). Associations between social COVID-19 exposure and items excluded from the EFA were examined individually. To examine associations between social COVID-19 exposure (yes/no) and COVID-19 concerns, anxiety, depression, and stress (aim 1), we used independent sample t-tests. To test the moderating effects of select socio-demographic characteristics (i.e., sex, age, and income) on the relationships between social COVID-19 exposure with COVID-19 concerns, anxiety, depression, and stress (exploratory aim 2), we used the PROCESS macro for SPSS (Hayes, 2022). All analyses were conducted using IBM SPSS, v. 26. The statistical significance was set to α = 0.05. Results Participant characteristics Participants were on average 50.6 (SD = 14.4) years old, slightly more than half self-identified as female (55%), and most were non-Hispanic (87%) and White (95%) with at least a college degree (67%). See Table 1 for more details.Table 1 Participant characteristics Variable Mean (SD), Range Age 50.63 (14.36), 18–84 n (%) Sex Female 189 (55.1) Male 154 (44.9) Race White 326 (95.0) Marginalizeda 17 (5.0) Education Less than 4-year college degree 108 (31.4) 4-year college degree or more 230 (67.1) Missing 5 (1.5) Ethnicity Non-Hispanic 297 (86.6) Hispanic 46 (13.4) Household size 1 66 (19.2) 2 153 (44.6) 3 53 (15.5) 4 38 (11.1) 5 19 (5.5) 6 or more 6 (1.8) Missing 8 (2.3) Children in the household 0 261 (76.1) 1 42 (12.2) 2 23 (6.7) 3 or more 9 (2.6) Missing 8 (2.3) Pre-tax income within the past year $0 to $9999 3 (0.9) $10,000 to $14,999 2 (0.6) $15,000 to $19,999 4 (1.2) $20,000 to $34,999 17 (5.0) $35,000 to $49,999 28 (8.2) $50,000 to $74,999 59 (17.2) $75,000 to $99,999 56 (16.3) $100,000 to $199,999 111 (32.4) $200,000 or more 39 (11.4) Missing 24 (7.0) a11 respondents identified their racial identity as “Other,” 1 as “Black or African American,”1 as “American Indian or Alaska Native,” 1 as “White & African American,” 1 as “White & African American & American Indian or Alaska Native,”1 as “White &African American & Other,” 1 as “White & Asian.” Social COVID-19 exposure Two hundred and twenty-two participants (65% of the sample) reported “no exposure”. Of those, 197 reported they did not know anyone with a COVID-19 diagnosis, and 21 answered “I don’t know” about whether they knew someone diagnosed with COVID-19. Four participants selected both responses. There were no differences for the outcomes of interest (p > 0.05) between those who answered “No” and “I don’t know.” The remaining 115 participants (34%) reported knowing someone who was either diagnosed or was suspected to have had COVID-19. Data from six participants were excluded because of either true missingness (n = 1; 0.3% of the sample) or endorsement of mutually exclusive answers (e.g., endorsing both knowing someone with a diagnosis or suspicion of COVID-19, and endorsing not knowing anyone with a known or suspected COVID-19 diagnosis [n = 5; 1% of the sample]). Psychological functioning: descriptive findings The proportion of participants positively screening for clinically significant anxiety or depression was 14% and 13%, respectively. See Table 3 for more details. Respondents were most concerned about a family member getting sick (55% indicated “very concerned”) and least concerned about Internet access (71% indicated “not concerned”) (Fig. 1). “Other concerns” received the highest proportion of “not applicable” responses (78% of respondents). Additional items that were endorsed as not applicable by most participants described parenting concerns.Fig. 1 Endorsement of individual COVID-19 concerns Exploratory factor analysis of COVID-19 concerns An initial analysis indicated that six factors had eigenvalues over the Kaiser criterion of 1 (Kaiser, 1960). These six factors explained 76.2% of the variance, which meets the recommended threshold of at least 50% of the total variance explained by the retained factors (Streiner, 1994). Items clustering on the same factor suggested that factor one represented work and financial concerns, factor two represented government protection concerns, factor three represented healthcare concerns, factor four represented lifestyle concerns, factor five represented social isolation concerns, and factor six represented parenting concerns (Table 2). All factors demonstrated good reliability assessed using Cronbach’s alpha (α range 0.73–0.94; see Table 2 for specific values).Table 2 Results of exploratory factor analysis for COVID-19 related concerns (n = 343) Rotated factor loadings for types of concerns Work and Financial Government protection Healthcare Lifestyle Social isolation Parenting Losing my job 0.932 Losing my health insurance 0.707 0.172 Not being able to work 0.907 Not being able to pay my bills 0.708 0.132 Being able to afford my retirement 0.549 Not being protected at work 0.441 0.158 − 0.126 0.129 My local government not doing enough to protect people 0.845 0.119 My state government not doing enough to protect people 0.982 US government not doing enough to protect people 0.923 Not being able to get healthcare if I get sick with Covid-19 0.836 Not being able to get healthcare for other problems that I have 0.878 Not being able to get healthcare for emergency situations 0.937 Not being able to exercise regularly 0.754 Not being able to eat healthy foods 0.803 Having Internet access 0.171 0.468 Being socially isolated 0.158 0.724 My family members being socially isolated − 0.101 0.909 Providing supervision for my children 0.789 My children’s ability to complete school 0.803 Eigenvalues 6.51 2.32 1.84 1.48 1.18 1.15 % of variance 34.28 12.22 9.77 7.78 6.20 6.05 Cronbach’s Alphas 0.87 0.94 0.91 0.73 0.82 0.79 Bolded numbers within each column indicate items that loaded onto the same factor Extraction Method: Maximum Likelihood Rotation Method: Promax with Kaiser Normalization Factor loadings below \|0.10\| were suppressed. The highest loading value for any given item that achieved at least 0.40 was the criterion for selection to represent the factor Table 3 The effect of social COVID-19 exposure versus no exposure on psychological outcomes Overall No Social COVID-19 exposure Social COVID-19 exposure n M (SD) n M (SD) n M (SD) t df Anxietya 335 1.19 (1.55) 220 1.04 (1.52) 115 1.46 (1.56) − 2.38* 333 Depressiona 335 1.09 (1.59) 220 1.01 (1.62) 115 1.23 (1.53) − 1.23 333 Perceived stressb 335 4.70 (3.20) 220 4.40 (3.14) 115 5.26 (3.24) − 2.37* 333 COVID-19 concerns (EFA)c Work and financial 336 1.52 (0.58) 221 1.47 (0.57) 115 1.59 (0.60) − 1.80 334 Government protection 336 2.12 (0.79) 221 2.05 (0.62) 115 2.18 (0.52) − 1.77 334 Healthcare 336 1.54 (0.71) 221 1.50 (0.70) 115 1.61 (0.73) − 1.42 334 Lifestyle 336 1.46 (0.55) 221 1.46 (0.55) 115 1.46 (0.56) 0.07 334 Social isolation 336 1.75 (0.66) 221 1.71 (0.69) 115 1.83 (0.59) − 1.67** 334 Parenting 335 1.19 (0.48) 220 1.16 (0.43) 115 1.25 (0.56) − 1.54 333 COVID-19 concerns (individual items) Family member getting sick 340 2.47 (0.63) 221 2.58 (0.51) 113 2.42 (0.68) − 2.25* 332 Getting sick oneself 342 2.13 (0.71) 221 2.17 (0.62) 115 2.12 (0.75) − 0.58 334 Drinking more or using substances more 340 1.22 (0.50) 220 1.30 (0.56) 114 1.17 (0.72) − 2.17* 332 Not being able to get tested if I develop symptoms 342 1.61 (0.74) 221 1.66 (0.72) 115 1.58 (0.75) − 0.96 334 aPatient Health Questionnaire-4, (PHQ-4), bPerceived Stress Scale-4 (PSS-4), cExploratory Factor Analysis *p ≤ 0.10; p < .05 Associations between social COVID-19 exposure and psychological functioning Participants with social COVID-19 exposure reported statistically significantly more concern about a family member getting sick (M = 2.58, SD = 0.51, p = 0.015), and concern about drinking more and using substances more (M = 1.24, SD = 0.64, p = 0.042) compared to those without social exposure (M = 2.42, SD = 0.68 and M = 0.99, SD = 0.66, respectively). Those with and without exposure did not differ on the remaining factor-analyzed categories of concerns (all ps > 0.05). As hypothesized, participants with social COVID-19 exposure reported statistically significantly more anxiety (M = 1.46, SD = 1.56, p = 0.018) and stress (M = 5.26, SD = 3.24, p = 0.018), although not more depression (M = 1.23, SD = 1.54, p > 0.05) than those without social exposure (M = 1.04, SD = 1.52; M = 4.40, SD = 3.14; M = 1.01, SD = 1.62, respectively; Table 3). Moderation analyses Knowing someone who had COVID-19 had more impact on the concerns of women, younger people, and people with incomes less than $100,000 per year. Biological sex emerged as a statistically significant moderator of the relationship between social COVID-19 exposure and concerns regarding government protection (b = 0.33, se = 0.16, p = 0.04) and healthcare (b = 0.32, se = 0.16, p = 0.05) (Fig. 2). Simple slope tests showed that women but not men who had social COVID-19 exposure had greater concerns regarding government (b = 0.27, se = 0.10, p = 0.01) and healthcare (b = 0.25, se = 0.11, p = 0.02) compared to those without exposure. Biological sex interacted with the relationship between social COVID-19 exposure and lifestyle concerns (b = 0.30, se = 0.12, p = 0.01), but neither the simple slope tests for women (b = 0.14, se = 0.08, p = 0.07) nor men (b = -0.16, se = 0.09, p = 0.09) were statistically significant.Fig. 2 Sex, income, and age as moderators of the relationship between social COVID-19 exposure and primary outcomes Age emerged as a statistically significant moderator of the relationships between social COVID-19 exposure and anxiety (b = − 0.04, se = 0.01, p = 0.002), and social exposure and depression (b = − 0.03, se = 0.01, p = 0.007). Participants younger than age 36 (i.e., those -1 SD on the centered age variable [whereby M = 50.6 and SD = 14.4]) who had social COVID-19 exposure reported more anxiety (b = 0.77, se = 0.23, p < 0.001) and depression (b = 0.59, se = 0.24, p = 0.02) than participants without exposure. Among older participants, anxiety and depression did not vary based on social COVID-19 exposure (ps > 0.05). Income was a statistically significant moderator of the relationship between social exposure and work and financial concerns (b = − 0.11, se = 0.04, p = 0.01). Participants whose annual household income was less than $100,000 and had social COVID-19 exposure experienced more work and financial concerns (b = 0.15, se = 0.07, p = 0.03) than those without exposure. Among those with incomes of more than $100,000, the relationship between social COVID-19 exposure and work and financial concerns was not statistically significant (p > 0.05). Discussion Using a sample from Tampa, Florida collected during the first COVID-19 pandemic wave in mid-June 2020, and drawing from the biopsychosocial model, we investigated associations between social COVID-19 exposure and psychological functioning, and whether these relationships varied by socio-demographic factors. We found that those with social COVID-19 exposure reported more anxiety and stress compared to those without exposure. This suggests that the widely reported increases in symptoms of anxiety (Jia et al., 2021) and stress (American Psychological Association [APA], 2019; APA, 2020) during the early stages of the pandemic may have been influenced, at least in part, by knowing about suspected or diagnosed COVID-19 cases in one’s social circle. Social COVID-19 exposure was associated with concerns about a family member getting sick, but not concerns about personal health, implying that anxiety and stress were driven more by thinking about the well-being of close others than one’s own vulnerability. This is consistent with research examining online COVID-19 narratives that identified worrying about close others as a substantial source of psychological distress (Hung et al., 2020). Those with social COVID-19 exposure were also more concerned about excessive alcohol consumption and substance use than those without exposure. This finding is in line with research linking personal COVID-19 experiences (e.g., having personally contracted the virus, knowing others in the community who had a case of, or died of, COVID-19) to the use of alcohol and substances in the general population (MacMillan et al., 2021), and could indicate that social exposure to COVID-19 is a risk factor for problematic use of alcohol and substances. The bidirectional nature of the relationship between social COVID-19 exposure and mental health should be acknowledged. It is possible that just as social COVID-19 exposure may lead to worsened psychological functioning, deterioration in mental health can create additional risk factors, including risky behaviors such as neglect of safety measures and low adherence to mitigative strategies (Trogen & Caplan, 2021) that could increase the risk of exposure to those infected with the COVID-19 virus. Research shows that certain segments of the U.S. population, including women (Kolakowsky-Hayner et al., 2021), younger people (Sojli et al., 2021), or persons with lower socioeconomic status (Lee & Singh, 2021) experienced more burdensome pandemic-induced mental health impacts compared to men, older people, and those with higher socioeconomic status, respectively. Our study suggests that this increased burden may translate to further adverse outcomes due to COVID-19 attributable social factors. Specifically, women who had social COVID-19 exposure reported greater government protection and healthcare concerns compared to women without exposure; younger people with exposure experienced more anxiety and depression than their counterparts without exposure; and those with less income who had social COVID-19 exposure experienced more work and financial concerns than those without. Women, younger adults, and lower income workers were also at a higher risk for losing employment and experiencing economic insecurity early in the pandemic (Office of Human Services Policy [HSP, 2021]). Thus, it is possible that knowing others who have been infected with COVID-19 increased the salience of perceived vulnerability within those groups, including to adverse financial sequalae of becoming ill with COVID-19, and the deterioration in psychological health. Additionally, it’s possible that women and younger people who knew others in their social circle with a COVID-19 infection stayed at home more to reduce their own chances for getting sick, and increased their exposure to environments that in some cases are detrimental to psychological well-being, for example, due to domestic violence (Huecker et al., 2022) or family tensions (Hall & Zygmunt, 2021). Men, older individuals, and people with higher income did not experience detrimental effects of social COVID-19 exposure to the same degree. This mental health crisis should be recognized as a public health emergency, and vulnerable individuals should be given priority in referrals to mental health services, such as those delivered digitally. Technology-based approaches have proved safe and effective models of mental health care delivery (Lecomte et al., 2020), and should be widely expanded to ensure that vulnerable populations receive the psychological services they need. Limitations Our study design was cross-sectional and represented associations between constructs at one time point during the pandemic. This precluded us from conducting mediational analyses and establishing what factors drive the associations between social COVID-19 exposure and psychological functioning. Longitudinal methods could offer a more comprehensive portrayal of how the extent to which members of one’s social networks contract an infectious disease impacts psychological functioning amidst a continually changing epidemiological situation, and what drives these effects. The question assessing social COVID-19 exposure, did not allow us to distinguish who in one’s social circle had a true COVID-19. COVID-19 diagnoses may have also led to vastly different health outcomes in those affected, from mild illness to death, and consequently varying levels of distress. Additionally, we grouped the “not applicable” responses together with the “not concerned” ones in the EFA, inferring that if a given complication was marked as not applicable by the respondent, then it likely posed no concerns for that person. However, the mechanism behind the “not applicable” responses may be different from what drives the “not concerned” answers, and by merging these together we potentially overlook qualitatively distinct experiences underlying these two types of answers. Further, most participants identified as White, which limits generalizability of the findings to other races and ethnicities, and precluded us from being able to examine whether or how the hypothesized associations between social COVID-19 exposure and psychological functioning might have varied by race and ethnicity. Conclusions Consistent with the biopsychosocial model, we found that a person’s psychological functioning can be associated with the health of their social circle, and that the consequences of social exposure for mental health outcomes are worse for socio-demographic groups that experience social and health inequities. Such populations are at heightened risk for negative mental health consequences due the pandemic and should be prioritized in mental health service delivery. The COVID-19 pandemic highlighted that health and disease outcomes are influenced by the dynamic interplay between biological, psychological and social factors. Increased incorporation of biopsychosocial approaches to clinical care, and public health should be a priority within the public health agenda. Authors' contributions ML, JH, EW, HO, MK, PK, and JH were responsible for the conceptualization of the study; PK was responsible for financially supporting data collection; ML, JH, JH, and ES were responsible for the data analysis; ML, JH, and JH drafted the manuscript; all authors contributed to editing the manuscript. Funding Work was supported in part by the Participant Research, Interventions and Measurement Core at the H. Lee Moffitt Cancer Center & Research Institute; an NCI designated Comprehensive Cancer Center (P30-CA076292). This work was supported by grants from the American Cancer Society (RSG-14-162-01-CPHPS) and the National Cancer Institute Ponce Health Sciences University-Moffitt Cancer Center Partnership (U54 CA163068). This research was also supported by NCI P30 CA008748 (Thompson). ML was further supported by T32CA00946 (Ostroff). Availability of data and material Data are available upon request from the corresponding author. Code availability Syntax are available upon request from the corresponding author. Declarations Conflict of interest None of the authors have conflicts of interest that would impact the unbiased reporting of study results. Consent to participate This study was deemed exempt from human subjects consideration by Advarra and an alteration of HIPAA authorization per 45 CFR 164.512(i)(ii) was granted; informed consent was not obtained from participants completing the survey. Consent for publication All authors give consent for publication. Peter A. Kanetsky and Jennifer L. Hay: Joint Senior Authors. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References American Psychological Association. (2019). Stress in America: Stress and current events. Stress in America™ Survey. https://www.apa.org/news/press/releases/stress/2019/stress-america-2019.pdf. American Psychological Association. (2020). Stress in America™ 2020: A national mental health crisis. https://www.apa.org/news/press/releases/stress/2020/sia-mental-health-crisis.pdf. Adams EL Smith D Caccavale LJ Bean MK Parents are stressed! patterns of parent stress across COVID-19 Front Psychiatry 2021 12 626456 10.3389/fpsyt.2021.626456 33897489 Butter S McGlinchey E Berry E Armour C Psychological, social, and situational factors associated with COVID-19 vaccination intentions: A study of UK key workers and non-key workers The British Journal of Health Psychology 2021 10.1111/bjhp.12530 33949038 Cohen S Kamarck T Mermelstein R A global measure of perceived stress Journal of Health and Social Behavior 1983 24 4 385 396 10.2307/2136404 6668417 Czeisler M Lane RI Petrosky E Wiley JF Christensen A Njai R Weaver MD Robbins R Facer-Childs ER Barger LK Czeisler CA Howard ME Rajaratnam SMW Mental Health, Substance Use, and Suicidal Ideation During the COVID-19 Pandemic - United States, June 24–30, 2020 MMWR. Morbidity and Mortality Weekly Report 2020 69 32 1049 1057 10.15585/mmwr.mm6932a1 32790653 Dragioti E Li H Tsitsas G Lee KH Choi J Kim J Choi YJ Tsamakis K Estradé A Agorastos A Vancampfort D Tsiptsios D Thompson T Mosina A Vakadaris G Fusar-Poli P Carvalho AF Correll CU Han YJ Solmi M A large-scale meta-analytic atlas of mental health problems prevalence during the COVID-19 early pandemic Journal of Medical Virology 2021 10.1002/jmv.27549 34709664 Engel GL The need for a new medical model: A challenge for biomedicine Science 1977 196 4286 129 136 10.1126/science.847460 847460 Hall LR Sanchez K da Graca B Bennett MM Powers M Warren AM Income differences and COVID-19: Impact on daily life and mental health Population Health Management 2021 10.1089/pop.2021.0214 34652228 Hall SS Zygmunt E “I Hate It Here”: Mental health changes of college students living with parents during the COVID-19 quarantine Emerging Adulthood 2021 9 5 449 461 10.1177/21676968211000494 Hayes, A. F. (2022). Introduction to mediation, moderation, and conditional process analysis: A regression-based approach (3rd ed.). Guilford Press. Holt-Lunstad J Robles TF Sbarra DA Advancing social connection as a public health priority in the United States The American Psychologist 2017 72 6 517 530 10.1037/amp0000103 28880099 Huecker, M. R., King, K. C., Jordan, G. A., & Smock, W. (2022). Domestic Violence. In StatPearls. StatPearls Publishing Copyright© 2022, StatPearls Publishing LLC. Hung M Lauren E Hon ES Birmingham WC Xu J Su S Hon SD Park J Dang P Lipsky MS Social network analysis of COVID-19 sentiments: Application of artificial intelligence Journal of Medical Internet Research 2020 22 8 e22590 10.2196/22590 32750001 The impact of the first year of the COVID-19 pandemic and recession on families with low incomes. (2021). Jia, H., Guerin, R. J., Barile, J. P., Okun, A. H., McKnight-Eily, L., Blumberg, S. J., Njai, R., & Thompson, W. W. (2021). National and state trends in anxiety and depression severity scores among adults during the COVID-19 pandemic—United States, 2020–2021 [Journal Article]. 70. https://stacks.cdc.gov/view/cdc/110409 (MMWR. Morbidity and mortality weekly report ; v. 70, early release, October 5, 2021) Kaiser, H. F. (1960). The application of electronic computers to factor analysis. Educational and Psychological Measurement, 20, 141–151. Kaiser HF Rice J Little Jiffy, Mark Iv Educational and Psychological Measurement 1974 34 1 111 117 10.1177/001316447403400115 Kolakowsky-Hayner SA Goldin Y Kingsley K Alzueta E Arango-Lasprilla JC Perrin PB Baker FC Ramos-Usuga D Constantinidou F Psychosocial impacts of the COVID-19 quarantine: A study of gender differences in 59 countries Medicina (kaunas, Lithuania) 2021 10.3390/medicina57080789 34440995 Kop, W. J. (2021). Biopsychosocial Processes of Health and Disease During the COVID-19 Pandemic. Psychosomatic Medicine, 83(4). https://journals.lww.com/psychosomaticmedicine/Fulltext/2021/05000/Biopsychosocial_Processes_of_Health_and_Disease.2.aspx. Kroenke K Spitzer RL Williams JB Löwe B An ultra-brief screening scale for anxiety and depression: The PHQ-4 Psychosomatics 2009 50 6 613 621 10.1176/appi.psy.50.6.613 19996233 Lacson JCA Doyle SH Del Rio J Forgas SM Carvajal R Gonzalez-Calderon G Ramírez Feliciano A Kim Y Roetzheim RG Sutton SK Vadaparampil ST Soto-Torres B Kanetsky PA A randomized clinical trial of precision prevention materials incorporating MC1R genetic risk to improve skin cancer prevention activities among hispanics Cancer Research Communications 2022 2 1 28 38 10.1158/2767-9764.CRC-21-0114 35845857 Lacson JCA Doyle SH Qian L Del Rio J Forgas SM Valavanis S Carvajal R Gonzalez-Calderon G Kim Y Roetzheim RG Sutton SK Vadaparampil ST Kanetsky PA A randomized trial of precision prevention materials to improve primary and secondary melanoma prevention activities among individuals with limited melanoma risk phenotypes Cancers (basel) 2021 10.3390/cancers13133143 34201795 Lecomte T Potvin S Corbière M Guay S Samson C Cloutier B Francoeur A Pennou A Khazaal Y Mobile apps for mental health issues: Meta-review of meta-analyses JMIR mHealth and uHealth 2020 8 5 e17458 10.2196/17458 32348289 Lee H Singh GK Monthly trends in self-reported health status and depression by race/ethnicity and socioeconomic status during the COVID-19 Pandemic, United States, April 2020 - May 2021 Annals of Epidemiology 2021 63 52 62 10.1016/j.annepidem.2021.07.014 34358622 Lightfoot E Moone R Suleiman K Otis J Yun H Kutzler C Turck K Concerns of family caregivers during COVID-19: The concerns of caregivers and the surprising silver linings Journal of Gerontological Social Work 2021 64 6 656 675 10.1080/01634372.2021.1898512 33724169 MacMillan T Corrigan MJ Coffey K Tronnier CD Wang D Krase K Exploring factors associated with alcohol and/or substance use during the COVID-19 pandemic International Journal of Mental Health and Addiction 2021 10.1007/s11469-020-00482-y 33519318 Osborne, J. (2014). Best practices in exploratory factor analysis. Otu A Charles CH Yaya S Mental health and psychosocial well-being during the COVID-19 pandemic: The invisible elephant in the room International Journal of Mental Health Systems 2020 14 38 10.1186/s13033-020-00371-w 32514302 Pachur T Hertwig R Steinmann F How do people judge risks: Availability heuristic, affect heuristic, or both? Journal of Experimental Psychology. Applied 2012 18 3 314 330 10.1037/a0028279 22564084 Panchal, N., Kamal, R., Cox, C., Garfield R. (2021). The Implications of COVID-19 for Mental Health and Substance Use KFF. Schulze C Hertwig R Pachur T Who you know is what you know: Modeling boundedly rational social sampling Journal of Experimental Psychology: General 2021 150 2 221 241 10.1037/xge0000799 32915018 Sojli E Tham WW Bryant R McAleer M COVID-19 restrictions and age-specific mental health—US probability-based panel evidence Translational Psychiatry 2021 11 1 418 10.1038/s41398-021-01537-x 34349100 Streiner DL Figuring out factors: The use and misuse of factor analysis Canadian Journal of Psychiatry 1994 39 3 135 140 10.1177/070674379403900303 8033017 Trogen B Caplan A Risk compensation and COVID-19 vaccines Annals of Internal Medicine 2021 174 6 858 859 10.7326/m20-8251 33646837 Tversky A Kahneman D Availability: A heuristic for judging frequency and probability Cognitive Psychology 1973 5 2 207 232 10.1016/0010-0285(73)90033-9 Tversky A Kahneman D Judgment under uncertainty: Heuristics and biases Science 1974 185 4157 1124 1131 10.1126/science.185.4157.1124 17835457 World Health Organization. (2022). WHO Coronavirus (COVID-19) dashboard. https://covid19.who.int/
PMC009xxxxxx/PMC9638215.txt	==== Front J Behav Med J Behav Med Journal of Behavioral Medicine 0160-7715 1573-3521 Springer US New York 36334167 368 10.1007/s10865-022-00368-5 Article Sleep and fatigue among youth with sickle cell disease: A daily diary study http://orcid.org/0000-0002-2175-1503 Johnston Julia D. [email protected] 1 Reinman Laura C. 2 Bills Sarah E. 1 Schatz Jeffrey C. 1 1 grid.254567.7 0000 0000 9075 106X Department of Psychology, University of South Carolina, 29208 Columbia, SC USA 2 grid.241116.1 0000000107903411 Department of Psychology, University of Colorado School of Medicine, 80045 Denver, CO USA 5 11 2022 2023 46 3 440450 18 3 2022 19 9 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Youth with sickle cell disease (SCD) experience disease effects including vaso-occlusive pain crises, poor sleep quality, and fatigue. The present study examines how sleep quality and pain medications impact fatigue in youth with SCD. Daily diaries assessing pain, fatigue, sleep quality, mood, and use of pain medications from 25 youth with SCD ages 11 to 18 years were collected for eight consecutive weeks. Poor sleep quality predicted increases in next-day fatigue levels while controlling for pain and mood. Sleep quality did not moderate the existing temporal relationship between pain and next-day fatigue established by Reinman et al. (2019) as predicted. Non-opioid medications affected ratings of next-day fatigue but opioid medications did not. Sleep quality appears to play an important role in predicting next-day fatigue levels and may be an important target for intervention. Pain medication use did not substantially contribute to prospective fatigue levels among youth, but requires further study. Keywords Sleep quality Fatigue Analgesics NIH-NIGMST32-GM081740 Bills Sarah E. issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction Sickle cell disease (SCD) describes a group of inherited blood disorders in which recurrent physical complications such as pain, anemia, fatigue, and infection negatively impact youth’s functioning (Brown, 2006). Medical interventions (e.g., oral hydroxyurea, transfusion therapy) reduce symptom severity, but children and adolescents still suffer from complications affecting daily functioning. The frequency of medical complications individuals experience increase with age, making adolescence a particularly challenging time for patients with SCD as they experience greater pain, increased risk for internalizing symptoms, and disruptions to daily life (Rees et al., 2010). Research utilizing daily diary methods have examined prospective relationships between symptoms like pain, mood, and sleep quality to better understand how symptoms influence each other (Valrie et al., 2007a, 2019). These studies have elucidated a cyclic relationship between increased pain and poorer sleep quality (Valrie et al., 2007b; Fisher et al., 2018) and associations between negative mood and increased pain. Daily diary studies are valuable as they demonstrate the strength and direction of associations between symptoms and functioning in youth with SCD. Despite a significant number of daily diary studies conducted among youth with SCD, few studies have examined factors influencing fatigue levels (Ameringer & Smith, 2011; Ameringer et al., 2014). Accumulating literature suggests fatigue is a primary and common concern among patients with SCD (Ameringer et al., 2014; Anderson et al., 2015; Dampier et al., 2010; While & Mullen, 2004), contributing to significant functional limitations and psychosocial concerns (Dampier et al., 2010). Specifically, nearly 70% of adolescents and young adults with SCD were found to experience moderate fatigue levels (Ameringer et al., 2014) and fatigue has been connected to increased school absences, internalizing symptoms, pain, stress, impaired cognitive functioning, poor sleep, and decreased health-related quality of life (HRQOL) (Ameringer et al., 2014; Anderson et al., 2015; Dampier et al., 2010). Youth have reported fatigue as one of the most difficult and disruptive symptoms to manage (Poku et al., 2020). Among adolescents with SCD, fatigue is chronic, characterized by persistent feelings of exhaustion unresolved with rest, and is influenced by behavioral, psychological, and physiological factors (Ameringer & Smith, 2010; Crichton et al., 2015; Shen et al., 2006). Ameringer and Smith (2010) proposed a biobehavioral model of fatigue in patients with SCD, which contextualizes these relationships by asserting that that person-level, disease-level, and moderating variables interact to produce poor outcomes (Ameringer & Smith, 2010; Hossain et al., 2005; Shen et al., 2006). This model converges with the conceptualization that primary (disease-level) and secondary (person-level) factors influence fatigue levels in youths with chronic illnesses (Ameringer & Smith, 2012; Maughan & Toth, 2014). In SCD, primary factors include inflammation, anemia, and overall disease severity, which is often denoted by genotype severity (Ameringer et al., 2014; Crichton et al., 2015; Maughan & Toth, 2014) whereas secondary factors include sleep quality, pain, and mood (Crichton et al., 2015; Ameringer & Smith, 2011). Fatigue has been associated with negative psychosocial outcomes while controlling for effects of disease-related variables (Anderson et al., 2015), suggesting fatigue is a unique source of poor adjustment beyond its correlation with disease symptomology. Among the factors influencing fatigue in SCD pain appears to play a large role and is a focus of the current study. Increased pain severity was recently shown to predict increased next-day fatigue severity in youth with SCD and increased fatigue was shown to predict increased next-day pain (Reinman, 2019). These data support a cyclic relationship between pain and fatigue in which pain severity accounted for greater variance in next-day fatigue than the alternative, suggesting pain may be the more potent driver of this cycle (Reinman et al., 2019). Fishbain and colleagues (2003) provide additional support for a causal relationship between pain and fatigue in a systematic review of studies across pain populations. Due to high functional impairment in youth experiencing pain and fatigue, behavioral interventions aimed at reducing these symptoms are clinically important. As such, identifying factors that prospectively contribute to fatigue and pain and respond to behavioral change may be significant for future clinical applications. Sleep quality influences both pain and fatigue and is particularly important for youth with SCD because sleep disorders, including restless leg syndrome, insomnia, and obstructive sleep apnea, are highly prevalent and many of these disorders can be alleviated with behavioral interventions (Rosen et al., 2014; Valrie et al., 2007b). Whereas the relationship between pain and sleep quality in SCD has been a prominent focus of research, the relationship between sleep and fatigue is not well understood. This may be partially explained by the difficulty defining and measuring the subjective, multidimensional nature of fatigue (Ameringer et al., 2014; Anderson et al., 2015). Even less research has examined the relationship between fatigue and sleep, which may be due to confusion surrounding the distinction between constructs. Sleep medicine has attempted to distinguish fatigue from daytime sleepiness or sleep propensity, defined as “one’s tendency to fall asleep” (Shen et al., 2006, p. 64). However, many researchers and clinicians continue to use these terms interchangeably (Crichton et al., 2015; Shen et al., 2006). An important distinction between sleepiness and fatigue is that while restorative sleep improves symptoms of sleepiness, it does not improve symptoms of fatigue (Shen et al., 2006; Hossain et al., 2005). Fatigue is further characterized by the presence of physical weakness, rest without reprieve of symptoms, cognitive symptoms such as memory and attention difficulties, and reduced motivation (Anderson et al., 2015; Shen et al., 2006). Of note, sleepiness is also characterized by some cognitive impairment, although research with youth with SCD has shown fatigue to more strongly impact neurocognitive and academic functioning compared to poor sleep quality (Rogers & Lance, 2017). Presently, only a few studies have cross-sectionally examined how sleep quality is related to fatigue severity in youth with chronic medical conditions. Poor sleep quality and sleep disturbances were associated with increased levels of fatigue in several studies (Butbul Aviel et al., 2011; Crosby 1991; Kanyak et al., 2006) and these findings were replicated in one cross-sectional study of youth with SCD (Ameringer et al., 2014). Biomarkers and biochemical responses present in SCD provide theoretical support for the relationship between sleep and fatigue. Inflammatory cytokines (i.e., specific interleukins and TNF-α), which are elevated in patients with high levels of fatigue and pain, have been shown to negatively impact sleep in patients with SCD, highlighting underlying mechanisms through which these symptoms may be associated (Ameringer & Smith, 2010; Klimas et al., 2012). In addition, inflammatory responses that mediate vaso-occlusive injury and are associated with symptoms of fatigue have been shown to relate to poor sleep quality (Ameringer et al., 2014). Pain was commonly comorbid in studies examining the relationship between fatigue and sleep, providing support for shared physiological mechanisms across these constructs (Ameringer et al., 2014; Butz Aviel et al., 2011). Studies showing inter-relationships among fatigue, increased pain and poor sleep quality indicate several important points for youth with SCD: Whereas Ameringer & Smith (2011) proposed that disrupted sleep mediates the relationship between pain and fatigue, research on SCD pathophysiology suggests it is more likely that poor sleep quality interacts with pain severity to influence prospective symptoms of fatigue in youth with SCD. This is because biological pathways underpin these relationship in sickle cell disease, with increased inflammation from pain and poor sleep likely exerting multiplicative effects on fatigue severity (Klimas et al., 2012; Butz Aviel et al., 2011). Further, research has shown that pain severity still influences fatigue levels while controlling for sleep quality, reducing the likelihood of a mediating relationship (Fishbain et al., 2003). Because mood has been shown to influence pain, fatigue, and sleep, this is an important factor that should be controlled for to understand the specifity of relationships. Researchers must also consider the effects of pain medications when examining how pain severity, sleep quality, and fatigue levels interact over time. Opioids are commonly used to treat sickle cell pain at home and in emergent settings (Stinson & Naser, 2003) and sedation is a potent side effect of analgesics, which may precipitate the onset of fatigue-like symptoms. As emphasized by other authors, studies exploring the association between pain and fatigue often fail to account for the effects of pain medications in data analyses and thus may report inflated or skewed levels of fatigue (Ameringer et al., 2014; Dampier et al., 2010; Fishbain et al., 2005). In addition, research has shown that opioids alter sleep structure (Dimsdale, 2007) and therefore may contribute to poor sleep quality in youth with pain. In a longitudinal daily diary study, Valrie and colleagues (2007b) demonstrated use of pain medication was associated with poor sleep, but pain medication dampened the negative effect of pain on sleep quality (Valrie et al., 2007a). It appears that while analgesic pain medications may decrease pain severity and attenuate pain’s impact on sleep quality, biochemical effects of opioids negatively impact sleep (Dimsdale, 2007; Onen et al., 2005; Valrie et al., 2007a). Based on current literature, it is unlikely non-opioid pain medications would impact fatigue levels as side effects of these medications are typically restricted to renal, gastrointestinal, and cardiovascular complications (Harirforoosh et al., 2013). While researchers investigating the pain-sleep relationship frequently control for use of medication (Fisher et al., 2018; Valrie et al., 2019), it is equally important to explore how the use of opioid and non-opioid analgesics impacts daily and prospective fatigue severity. The present study aims to extend current findings by identifying how sleep and use of pain medications contribute to prospective fatigue severity in adolescents with SCD (Ameringer & Smith, 2011; Ameringer et al., 2014) while controlling for effects of mood. Poor sleep quality and the use of opioid pain medications are expected to predict increased next-day fatigue wheras use of non-opioid medications (e.g., ibuprofen, Tylenol) is not. Sleep quality is hypothesized to moderate the relationship between pain severity and next-day fatigue severity. Methods Participants Thirty two youths between the ages of 11 and 18 with a clinical diagnosis of sickle cell disease by a hematologist (confirmed by chart review) and a primary caregiver were recruited from a Center for Cancer and Blood Disorders (CCBD) at a children’s hospital in the southeastern US after IRB approval. Additional inclusion criteria required English fluency and daily access to the internet. Youth with acute medical complications (e.g., admission for surgery), or those with major developmental disorders (i.e., autism spectrum disorders, intellectual disability) or significant cognitive impairments (e.g., those who had experienced an overt stroke) were excluded due to possible limitations in their ability to provide accurate and valid self-report data. Final inclusion criteria required youth to complete 9 or more daily diaries and consecutive diaries such that youth contributed data to both same-day and lagged analyses, resulting in 25 participants included in the final analyses. Procedure Participants were recruited after their routine healthcare appointment as part of a larger study occurring before the COVID-19 pandemic (Reinman, 2019). Researchers met with eligible participants and their caregivers to discuss the purpose and methodology of the study. Following written participant assent and caregiver informed consent, parents and youth completed baseline measures as part of the larger study. Measures collected at baseline will not be described in detail as they are not central to the present study. Daily health diaries, which have been established as a valid methodology among youth with chronic illnesses (Gil et al., 2000) and utilized in previous studies involving youth with SCD (Valrie et al., 2007a) were used to collect longitudinal data. Participants received instructions on how to complete the diary and were asked to complete their daily diary at the same time after school for eight consecutive weeks during the academic school year. Daily diaries were expected to take between 10 and 15 min to complete using an online survey generator estimate; however, most youth completed diaries within five minutes. Participants received an email from researchers between 1:00–2:00pm and would click a unique URL code (e.g., tablet, computer, or smartphone) to complete the diary. Reminder texts were sent to participants’ cell phones if they had not completed their daily diary survey by 5:00pm. For every 10 diaries completed, participants received a $10.00 gift card. Follow-up contacts were made via text, phone, or email if participants had not completed diaries for three consecutive days. Data were collected via an online survey platform with a secure interface. Measures Demographic information including participant age, sex, and genotype was collected via the Psychosocial Assessment Tool 2.0 (PAT 2.0), a caregiver report measure commonly used among patients with chronic medical conditions such as cancer and sickle cell disease (Karlson et al., 2012). Baseline characteristics of pain, fatigue, depression, and anxiety were measuring using a pain history interview with the caregiver (Schlenz et al., 2016), the Pediatic Quality of Life Inventory Multidimensional Fatigue Scale (PedsQL MFS) (Anderson et al., 2015), the Child Depression Inventory, 2nd edition (CDI-2) (Kovacs & Staff, 2003), and the Multidimensional Anxiety Scale for Children, 2nd edition (MASC-2) (Baldwin & Dadds, 2007). These measures were collected at the time of study enrollment. Pain & Pain Medication Daily pain and use of medication were indexed with two items. Participants rated daily pain on an 11-point numeric rating scale (NRS) anchored by 0 “no pain whatsoever” and 10 “worst pain imaginable”. Numeric rating scales have been established to yield reliable and valid measurements of pain (Breivik et al., 2008; Wong & Baker, 1988). A second item assessed whether (a) participants had taken any medications for pain and (b) whether this medication was an opioid (e.g., codeine, morphine) or a non-opioid (e.g., ibuprofen, acetaminophen) pain medication. Fatigue: Daily fatigue was measured with 3 items assessing fatigue’s (1) severity, (2) bother, and (3) interference on a 0–10 NR. This 3-item measure, (Daily Fatigue Report Form), was developed by Erickson et al., (2010) and used among youth with cancer. Similar measures have been used to measure daily fatigue in other disease populations (Ream et al., 2006; Schwartz, 2000). In the present study, fatigue severity was used in multi-level model analyses for several reasons: (1) empirical support for use of single item measures of fatigue (Berger & Higginbotham, 2000), (2) Erikson et al.’s (2010) finding strong correlations between these three characteristics of fatigue with fatigue severity emerging as the most sensitive indicator of change over time, and (3) the greater influence of other psychological constructs on ratings of bother and interference. Youth were provided with a definition of fatigue as part of completing the baseline PedsQL Multdimensional Fatigue measure. No participants posed questions about the construct of fatigue during the study. Sleep quality Sleep quality was measured with one item. Participants rated the quality of their prior nights’ sleep on a 0–10 NRS with 0 indicating “poor” sleep and 10 indicating “ideal” sleep quality. This method of assessing sleep quality has been used in a number of studies including youth with SCD and is established as reliable and valid (Bromberg et al., 2012; Valrie et al., 2007b). Mood Mood was assessed using the Positive and Negative Affect Schedule for Children (PANAS-C), a 27-item scale was developed based on personality dimensions of extraversion and neuroticism and measures positive affect (PA) and negative affect (NA). Participants rate items on a 1–5 likert scale to yield total scores for positive and negative affect, measured by 12 and 15 items, respectively. This scale has been shown to strongly relate to internalizing symptoms in youth and is a widely used measure of mood valence (Watson et al., 1988). It has demonstrated strong reliability and utility in youth with chronic illnesses (Zempsky et al., 2013). Planned statistical analyses Data were analyzed using R statistical software (version 4.1.2). Preliminary intraclass correlations were run to identify the strength of intercorrelation among variables and assess for concerns about multicollinearity. Multilevel modeling analyses (MLM) were run to evaluate the temporal relationship between variables of sleep quality, pain, use of pain medication, and fatigue levels. MLM analyses were modeled after previous daily diary research studies (Gil et al., 2003; 2004; Schatz et al., 2015; Valrie et al., 2007; 2008). A three-step approach was taken for the analyses: (a) fitting an error structure to correct for serial dependency, (b) modeling age (child, adolescent), gender (male, female) and sickle cell genotype, which can indicate disease severity (moderate [HbSC, HbSβThal+] severe [HbSS, HbSβ0]), to determine their inclusion as covariates, and (c) adding the predictors. As part of fitting an error structure, a “Day” variable was included, in order to correct for serial dependency by days in the study. For the error structure, an auto-regressive, moving average (ARMA) was used. A person-level predictor of each dependent variable was added to control for between-person effects, consistent with similar studies using multilevel modeling in SCD (Gil et al., 2003; 2004; Valrie et al., 2007; 2008). The appropriateness of the MLM analyses was tested in each statistical model through one-way analysis of variance (ANOVA) to test for significant between groups variance and random coefficient regression models to test for a significant pooled within groups slope and significant variance in intercepts and slopes. To test the statistical significance of the multi-level regression models we used a likelihood ratio test that compared the − 2 log likelihood of the model with the full set of predictors to a model model with only the “Day” variable included as predictor. The effect size of associations within the regression models are reported using Cohen’s d. The assumptions of linearity, homogeneity of variance, and normally distributed residuals were examined through visual inspection of graphs plotting: the model residuals versus each predictor variable, fitted values versus residuals, and a histogram of the residuals, respectively. Given the dearth of studies in this area, a test-wise alpha level of 0.05 was chosen to interpret the hypotheses. Results Preliminary analyses Of the original 32 youth recruited in the present study, 25 youth (Mage = 14.3, SD = 1.9, 60% = male) between the ages of 11 and 18 with a clinical diagnosis of sickle cell disease completed 9 or more diaries, including consecutive diaries, and were included in the final study data set. Because all analyses involved lagged variables, diaries that had missing values for next-day variables (N = 175) were excluded, resulting in a final data set with 644 diaries of the total 819 diary entries completed by participants (Table 1). The 644 diaries included 191 days with pain, 62 days with moderate-to-severe pain (pain scores of ≥ 4), 260 days with fatigue, 84 days with moderate-to-severe fatigue (fatigue scores of ≥ 4) and 64 days with medication use (42 non-opioid, 22 opioid). Youth who met inclusion criteria for daily diaries did not differ from youth who did not complete diaries on baseline characteristics. Baseline characteristics for depressive symptoms, anxiety, and general fatigue can be found in Table 1 and indicate youth in this sample experience a high number of fatigue symptoms and generally report average to high average internalizing symptoms. Of the 25 youth included in the final data set, seven were children (11–12 years old) and eighteen were adolescents (13–18 years old). Additional demograpic (e.g., race/ethnicity, genotype) and descriptive statistics can be found in Table 1. Table 1 Sample demographics and daily diary descriptive information Variable N M ± SD MDN R F Age (years) - 14.3 ± 1.9 14.2 11.3–18.5 Gender Male Female) 15 (60%) 10 (40%) - - Genotype Severe: HbSS HbSβthal0 Moderate: HbSC HbSβthal+ 16 (64%) 2 (8%) 4 (16%) 3 (12%) - - - - - - - - Baseline Variables Pain episodes over prior 12 months* Lasting more than 4 h + medical visit Lasting more than 4 h + no medical visit Lasting less than 4 h 25 25 25 0.9 ± 1.4 3.9 ± 9.9 0.6 ± 1.2 0 1 0 0–5 0–50 0–5 Multidimensional Fatigue – General (possible scores (0-100) 25 60.5 ± 16.8 62.5 12.5–87.5 CDI – norm referenced T-score 25 57.0 ± 10.6 57 40.0–84.0 MASC – norm referenced T-score 25 58.0 ± 11.6 57 40.0–75.0 Daily Diary Features Number of diaries 819 32.0 ± 17.0 31 9.0–56.0 Number of diaries with any pain 243 (30%) Pain intensity on days with pain (range 1–10) 2.9 ± 2.3 2 1.0–10.0 Number of diaries with any fatigue 260 (32%) Fatigue intensity on days with fatigue (range 1–10) 3.0 ± 3.4 2 1.0–10.0 Days with non-opioid pain medicine use 57 (7%) Days with opioid pain medicine use 27 (3%) Daily Diary Variables (possible scores) Fatigue (0–10 scale) 1.2 ± 2.1 0 0–10 Pain (0–10 scale) 0.9 ± 1.8 0 0–10 Sleep Quality (0–10 scale) 7.3 ± 2.6 8 0–10 Positive Affect (12–60 scale) 36.3 ± 15.9 36 12–60 Negative Affect (15–75 scale) 18.0 ± 5.3 15 15–54 Opioid medication use (yes/no) 42 (7%) Non-opioid medication use (yes/no) 22 (3%) Notes: M = mean, MDN = median, SD = standard deviation, R = range, F = frequency of “yes” responses, Pain history was from caregiver report at enrollment with emergency department or inpatient medical visits counting as a medical visit, CDI = Children’s Depression Inventory, 2nd edition; MASC = Multidimensional Anxiety Inventory for Children, 2nd edition Examination of intra-class correlations among the independent and dependent variables indicated very-small-to-medium associations (range 0.043 – 0.586) among variables except for the association of pain severity and use of opioid pain medication, r = .760, which is high enough to raise concerns about multicollinearity for the analyses including opioid pain medication use. Follow-up diagnostics for these statistical models indicated the variance inflation factor (VIF) scores for all variables were less than two, which is not indicative of multicollinearity concerns. For all analyses of study hypotheses we tested the impact of our decision to drop participants with few diary entries (n = 7) from the final data set and determined these choices did not bias the study outcomes. We compared MLM models including data from all 32 participants versus the final data set. Analyses conducted with all 32 participants and the final 25 participants produced the same the outcomes for study analyses based on p-levels and similar strengths of associations between variables, though the excluded participants contributed modest data to impact the findings. All MLM models met the assumptions as described in the planned statistical analyses, above. All tests of the impact of level 2 variables (i.e., age group, gender, sickle cell genotype severity) did not indicate they were related to the dependent variable and therefore they were not included as covariates. Study hypotheses The associations between use of prior-day pain medication, prior-night sleep quality and next-day fatigue were examined while controlling for the effects of prior-day affect and fatigue (Model 1). It was predicted that the poor prior-night sleep quality and use of analgesic pain medications would predict increases in next-day fatigue levels and that non-opioid medications (e.g., ibuprofen, Tylenol) would not affect next-day fatigue levels. The overall model for this regression was statistically significant, χ2 = 101.66, p < .001, R2 = 0.38 (see Table 2). Poor prior night’s sleep quality t(611) = -4.121, p < .001, d = 0.33, greater prior-day pain severity t(611) = 3.58, p < .001, d = 0.29, and use of non-opioid pain medication from the previous day t(611) = 2.21, p = .03, d = 0.18, predicted increased levels of next-day fatigue in youth while controlling for effects of the prior day’s fatigue levels t(611) = 4.60, p < .001, d = 0.37, negative affect t(611) = 2.72, p < .01, d = 0.22, and positive affect t(611) = − 0.77, p = .44, d = 0.06. Table 2 Effects of prior-night sleep quality and pain medication use on next-day fatigue levels B SE 95% CI t p Variable Fatigue Severity Intercept Day 1.57 − 0.02 0.44 0.01 0.71, 2.44 − 0.03, − 0.02 3.56 -4.03* < 0.001 < 0.001 Person-Level Fatigue (C) Fatigue Severity (C) Sleep Quality (C) 1.73 0.42 − 0.37 0.31 0.09 0.09 1.09, 2.37 0.24, 0.60 − 0.55, − 0.20 5.60* 4.60* -4.12* < 0.001 < 0.001 < 0.001 Pain Severity (C) Positive Affect (C) Negative Affect (C) Opioid Pain Medication Non-Opioid Pain Medication 0.29 − 0.01 0.04 0.66 0.66 0.08 0.01 0.02 0.44 0.30 0.13, 0.44 − 0.02, 0.01 0.01, 0.07 − 0.21, 1.54 0.07, 1.25 3.58* -0.77 2.72** 1.50 2.21* < 0.001 0.440 0.007 0.135 0.027 Notes: (C) denotes variables were centered Next, the moderating effect of prior-night sleep quality on the relationship between prior-day pain and next-day fatigue was examined (Model 2). The overall model for this regression was statistically significant, χ2 = 89.65, p < .001, R2 = 0.39 (see Table 3). However, the interaction between prior night’s sleep quality and prior-day pain severity t(614) = -0.81, p = .42, d = 0.07, did not predict greater next-day fatigue severity, while controlling for prior night’s sleep quality t(614) = -5.97, p < .001, d = 0.48, pain severity t(614) = 2.80 p < .001, d = 0.23, and prior day fatigue levels t(614) = 5.55, p < .001, d = 0.45. Table 3 Moderating influence of sleep quality on pain-fatigue relationship B SE 95% CI t p Variable Next-Day Fatigue Severity Intercept Day 2.31 − 0.02 0.17 0.01 1.98, 2.65 − 0.03, − 0.01 13.51* -4.37 < 0.001 < 0.001 Person-Level Fatigue (C) Fatigue Severity (C) 2.03 0.50 0.30 0.09 1.41, 2.64 0.32, 0.68 6.88* 5.55* < 0.001 < 0.001 Previous Night’s Sleep Quality (C) Pain Severity (C) Sleep Quality (C) X Pain (C) − 0.48 0.23 − 0.05 0.08 0.08 0.06 − 0.64, − 0.32 0.07, 0.39 − 0.17, 0.07 -5.97* 2.80 -0.81 < 0.001 0.005 0.418 Notes: (C) denotes variables were centered Post hoc analyses The daily diary variables for fatigue intensity, pain severity, and sleep demonstrated skew with significantly more data points at the low end of the scale for fatigue and pain and at the high end of the scale for sleep quality. Although there were no outliers detected, we evaluated the impact of this skewness on Model 1 by recoding the 11-point scales to four-point ordinal scales (for pain and fatigue: 0 vs. 1,2,3 vs. 4, 5, 6 vs. 7, 8, 9,10; for sleep: 10 vs. 7,8,9 vs. 4,5,6, vs. 0,1,2,3). This resulted in at least 21 data points at all levels of these variables. We sequentially tested the impact of using a four-point scale for each of these variables while keeping the others in their original scaling in testing the outcomes shown in Table 2. In each of these analyses the model predicting next-day fatigue levels showed attenuated associations related to the truncated variable, but the p–levels for pain, sleep quality, and negative affect still surpassed the study alpha as significant predictors of next-day fatigue. Discussion The present study aimed to elucidate prospective relationships between sleep quality, pain medications, and fatigue levels among youth with sickle cell disease while controlling for effects of mood. Our first hypothesis, which posited prior-night sleep quality and opioid (but not non-opioid) medications would predict fatigue (Model 1) was partially supported. Specifically, poor prior-night sleep quality predicted increased levels of next-day fatigue among youth while controlling for prior-day fatigue, pain severity, negative affect, and positive affect. Increased prior-day pain and negative affect also contributed to fatigue levels in a positive direction consistent with prior research. These data provide converging evidence for prior cross-sectional studies showing an association of sleep and fatigue by using measures of these constructs collected in a more naturalistic setting and less reliant on retrospective memory (Ameringer et al., 2014; Rogers & Lance, 2017). Although we assessed prior night sleep quality and fatigue in a manner that suggests a temporal association, participants would have reported these two variables within the same diary. Thus, there is a strong suggestion of a temporal order for these variables but it is possible that participant’s current fatigue level biased their report of prior-night sleep quality. The effects of pain medications on next-day fatigue were examined for two reasons: the limited literature examining effects of pain medications on fatigue levels among youths with chronic illness and the widespread limitation in prior research studies to account for the effects of pain medications in understanding fatigue. Contrary to expectations, use of opioid pain medications did not predict increases in next-day fatigue levels and non-opioid pain medications predicted increases in prospective fatigue levels. Non-opioid pain medications used by participants in this study included non-steroidal anti-inflammatory drugs (NSAIDs) and non-opioid analgesics (acetaminophen). The reason for this significant finding is unclear. Given NSAIDs decrease inflammation, which typically accompanies fatigue, it is unlikely non-opioid analgesic medications account for increased fatigue levels. A notable feature of our data was that the frequency of using non-opioid medication on days with pain was much lower than reported in prior studies of home-based pain management using daily diary methods. For example, Dampier et al., (2002) reported youth using non-opioid pain medication on 71% of days with pain and using opioid medications on 14% of days with pain whereas our sample reported using non-opioid pain medication on 23% of days with pain and opioid medications on 10% of days with pain. Given the relatively low use of non-opioid pain medication on days with pain, it is possible that use of non-opioid pain medication acted as a proxy for some other factor that we did not evaluate in our study. Why opioid medications were not found to influence fatigue levels is also unclear, but is consistent with the lack of consensus regarding the general association between opioids and fatigue levels among patients with pain disorders (Ameringer et al., 2014; Fishbain et al., 2005; Valrie et al., 2007a, b). In a review of medications proposed to affect fatigue, opioids did not significantly contribute to persistent levels of fatigue (Zlyott & Byrne, 2010). However, significant evidence supports opioids should produce fatigue given delays between plasma concentration of opioids and perceived effects (Lotsch, 2005) and half-lives of long-acting opioids used to treat pediatric sickle cell pain lasting up to seven hours (Ballas et al., 2012). Our study may have been limited in its ability to detect these types of relationships due to the low number of days with reported use of opioid medications. The expected relationship outlined in our second hypothesis between prior-night sleep quality, pain severity, and next-day fatigue examined in Model 2 was not supported. Specifically, sleep did not moderate the impact of prior-day pain on next-day fatigue levels in youth. Several reasons that could explain these findings. First, variability of pain severity scores reported across daily diary studies completed at home is typically limited. Although the number of days in which youth reported pain was consistent with prior daily diay studies (Dampier et al., 2002), there were relatively few days with moderate-to-severe levels of pain (n = 76, 9% of diaries) and not all participants had diary days with moderate-to-severe pain. This could reduce the statistical power and generalizability of our observed null interaction effect. As such, future research should examine this relationship in other samples involving youth reporting a greater number of days with moderate-to-severe pain. Ameringer & Smith (2011) had proposed sleep may mediate the relationship between pain and fatigue. While this relationship is feasible, we believed sleep would exert a moderating effect given vaso-occlusive pain and poor sleep quality activate shared inflammatory pathways that likely contribute to increased fatigue (Gutstein, 2001; Reese et al., 2010). We did not examine a mediating effect of sleep because our data did not show a significant relationship between pain severity and sleep quality, in contrast to prior research (Valrie et al., 2008; Valrie et al., 2007b; Valrie et al., 2018). These findings are notable and could be explained by the novel inclusion of fatigue in our model, which may change the observed effect of pain severity on sleep quality. Third, methodological differences, such as the use of different measures assessing constructs of sleep and pain (e.g., NRS vs. VAS, brief vs. full inventories) across studies, could contribute to differential findings. In summary, it is possible that methodogical factors led to our null finding for an interaction between pain and sleep quality or that sleep and pain exert independent effects on next-day fatigue levels. Although the interaction effect was not observed as predicted for our second hypothesis, this analysis also provides support that prior-night sleep quality is related to prospective fatigue levels. This temporal association is meaningful in that it provides support for the distinction between the the constructs of sleep quality and fatigue (Kanyak et al., 2006; Shen et al., 2006) while controlling for effects of prior-day fatigue and mood. Had sleep quality demonstrated an unusually large predictive effect on next-day fatigue levels, an interpretation of findings could be that the constructs were treated as synonymous by the participants. Because the symptoms of these constructs do overlap, further distinguishing conceptual and practical characteristics between these constructs is warranted (Shen et al., 2006). It is important to note that our findings do not capture the cumulative impact of poor sleep quality over multiple nights on youth’s fatigue levels. Poor sleep quality across an extended period of time may differentially predict fatigue levels among youth with chronic illnesses (Dawson & McCulloch, 2005) and is an important future direction. Researchers should make efforts to examine how poor sleep quality cumulatively affects fatigue levels among youth with SCD, especially given that sleepiness can be distinguished from fatigue. The biobehavioral model of fatigue presently does not include sleep quality (Ameringer & Smith, 2011). Revisions to this model are warranted, as findings from the present study align with the conceptualization that poor sleep quality contributes to increased fatigue among patients with chronic diseases (Ancoli-Israel et al., 2001). The magnitude of our effects suggested sleep quality may be more robust than pain in accounting for symptoms of fatigue, likely due to the prevalence of lower sleep quality and fatigue occurring in the absence of pain. The influence of sleep quality on prospective fatigue severity among youth with SCD is likely underappreciated. Sickle cell patients demonstrate a high prevalence of sleep disorders, anemia, and inflammation, all of which confer increased risk for fatigue (Brown, 2006; Gutstein, 2001; Rosen et al., 2014). Sleep quality and fatigue, therefore, are important targets for clinical interventions given fatigue has a negative impact on psychosocial functioning, QOL, and academic success (Anderson et al., 2015; Dampier et al., 2010; Rogers & Lance, 2017). Medical treatments are available that can address sleep disorders such as sleep apnea and improve sleep quality in SCD (Farrell et al., 2018). Cognitive and behavioral interventions including sleep hygiene education, relaxation strategies (e.g., mindfulness, imagery), bedtime restriction, and cognitive restructuring have been shown to improve sleep quality among youth with sleep difficulties and cognitive behavioral therapy has shown reductions in clinical fatigue among youth with chronic medical conditions (Åslund et al., 2018; Boonstra et al., 2019). Limitations are important to consider when evaluating findings from the present study. First, self-reported sleep quality and self-reported fatigue may have been at least partially conflated by participants, given that these constructs have nuanced distinctions. Despite efforts made to distinguish between constructs of sleep and fatigue, the predictive effect of sleep on fatigue observed in this study could be inflated. Efforts made in the current study to minimize the overlap between sleep and fatigue included providing youth with a definition and list of fatigue symptoms in baseline questionnaires and controlling for effects of prior-day fatigue in models. Future studies measuring both fatigue and sleep quality should consider additional efforts to operationalize sleepiness and fatigue for youth to help them distinguish between these constructs. Further, it could be beneficial to include a measure of daytime sleepiness when measuring daytime fatigue to control for this effect. Second, daily diary studies typically involve small sample sizes and findings may not generalize to the broader population. Based on the benchmarks suggested by Cohen (1988), the present study was able to detect small effect sizes and therefore appeared to have adequate in statistical power. Future studies should attempt to replicate research findings with larger samples including sickle cell patients of varying age, genotype, and location within the US. Additionally, most participants provided data with missing diary days, consistent with prior daily diary studies with this population. Researchers should identify effective strategies to boost adherence rates for diary completion and recommend standardized procedures that can be used for daily diary studies. Finally, although we used a daily measure of fatigue that was similar to measures used in previous research (Ream et al., 2006; Schwartz, 2000), the reliability and validity of our measure of daily fatigue should be explored. Researchers and clinicians should develop an agreed-upon definition of fatigue among sickle cell patients to aid in advancing understanding of this construct and its effects on patients. In summary, sleep was found to independently predict prospective fatigue severity among youth, but did not moderate the pain-fatigue relationship. No significant effects of opioid medications on fatigue were noted, though we observed significant effects of non-opioid medications on prospective fatigue levels that were unexpected and likely represent a methodological artefact. Future research should attempt to elucidate the ways in which pain medications affect fatigue levels in sickle cell patients. Taken together, these findings suggest sleep hygiene and other interventions to improve sleep are important for improving the functioning of youth because adequate sleep quality may attenuate a negative cascade of symptoms which includes fatigue. Future research efforts devoted to developing effective interventions to promote adaptive outcomes for youth with sickle cell disease are needed. Funding This publication was made possible in part by Grant Number T32-GM081740 from NIH-NIGMS. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIGMS or NIH. Availability of data and material Available upon request. Code Availability Available upon request. Conflict of interest None. Ethics approval Approved by university and hospital IRB systems. Consent to participate Written assent and consent obtained. Consent for publication Written assent and consent obtained. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Ameringer S Elswick RK Smith W Fatigue in Adolescents and Young Adults With Sickle Cell Disease: Biological and Behavioral Correlates and Health-Related Quality of Life Journal of Pediatric Oncology Nursing 2014 31 1 6 17 10.1177/1043454213514632 24378816 Ameringer S Smith WR Emerging Biobehavioral Factors of Fatigue in Sickle Cell Disease Journal of Nursing Scholarship 2011 43 1 22 29 10.1111/j.1547-5069.2010.01376.x 21342421 Ancoli-Israel S Moore P Jones V The relationship between fatigue and sleep in cancer patients: A review European Journal of Cancer Care 2001 10 4 245 255 10.1046/j.1365-2354.2001.00263.x 11806675 Anderson LM Allen TM Thornburg CD Fatigue in Children With Sickle Cell Disease: Association With Neurocognitive and Social-Emotional Functioning and Quality of Life Journal of Pediatric Hematology Oncology 2015 37 8 6 10.1097/mph.0000000000000431 Åslund L Arnberg F Kanstrup M Lekander M Cognitive and behavioral interventions to improve sleep in school-age children and adolescents: a systematic review and meta-analysis Journal of Clinical Sleep Medicine 2018 14 11 1937 1947 10.5664/jcsm.7498 30373682 Baldwin JS Dadds MR Reliability and validity of parent and child versions of the multidimensional anxiety scale for children in community samples Journal of the American Academy of Child & Adolescent Psychiatry 2007 46 2 252 260 10.1097/01.chi.0000246065.93200.a1 17242629 Ballas SK Gupta K Adams-Graves P Sickle cell pain: A critical reappraisal Blood 2012 120 18 3647 3656 10.1182/blood-2012-04-383430 22923496 Berger AM Higginbotham P Correlates of fatigue during and following adjuvant breast cancer chemotherapy: a pilot study Oncology Nursing Forum 2000 31 9 1443 1448 Boonstra A Gielissen M van Dulmen-den Broeder E Blijlevens N Knoop H Loonen J Cognitive behavior therapy for persistent severe fatigue in childhood cancer survivors: a pilot study Journal of Pediatric Hematology/Oncology 2019 41 4 313 318 10.1097/MPH.0000000000001345 30475298 Breivik H Borchgrevink PC Allen SM Rosseland LA Romundstad L Breivik Hals EK Kvarstein G Stubhaug A Assessment of pain British Journal of Anaesthesia 2008 101 1 17 24 10.1093/bja/aen103 18487245 Bromberg MH Gil KM Schanberg LE Daily sleep quality and mood as predictors of pain in children with juvenile polyarticular arthritis Health Psychology 2012 31 2 202 209 10.1037/a0025075 21842997 Brown, R. T. (2006). Comprehensive handbook of childhood cancer and sickle cell disease: A biopsychosocial approach. Oxford University Press Cohen J Statistical Power Analysis for the Behavioral Sciences 1988 2 Hillsdale, NJ Lawrence Erlbaum Associates, Publishers Crichton A Knight S Oakley E Babl FE Anderson V Fatigue in Child Chronic Health Conditions: A Systematic Review of Assessment Instruments Pediatrics 2015 135 4 e1015 e1031 10.1542/peds.2014-2440 25802352 Crosby LJ Factors which contribute to fatigue associated with rheumatoid arthritis Journal of Advanced Nursing 1991 16 8 974 981 10.1111/j.1365-2648.1991.tb01803.x 1779087 Dampier, C., Ely, B., Brodecki, D., & O’Neal, P. (2002). Characteristics of pain managed at home in children and adolescents with sickle cell disease by using diary self-reports. Journal of Pain. Dec;3(6):461 – 70. doi: 10.1054/jpai.2002.128064. PMID: 14622732 Dampier C Lieff S LeBeau P Rhee S McMurray M Rogers Z Smith-Whitley K Wang W Health-related quality of life in children with sickle cell disease: A report from the Comprehensive Sickle Cell Centers Clinical Trial Consortium Pediatric Blood & Cancer 2010 55 3 485 494 10.1002/pbc.22497 20658620 Dimsdale JE The Effect of Opioids on Sleep Architecture Journal of Clinical Sleep Medicine 2007 3 1 4 Erickson JM Beck SL Christian B Dudley WN Hollen PJ Albritton K Sennett MM Dillon R Godder K Patterns of Fatigue in Adolescents Receiving Chemotherapy Oncology Nursing Forum 2010 37 4 444 455 10.1188/10.ONF.444-455 20591804 Farrell AN Goudy SL Yee ME Leu RM Landry AM Adenotonsillectomy in children with sickle cell disease and obstructive sleep apnea International Journal of Pediatric Otorhinolaryngology 2018 111 158 161 10.1016/j.ijporl.2018.05.034 29958601 Fishbain DA Cole B Cutler RB Lewis J Rosomoff HL Fosomoff RS Is Pain Fatiguing? A Structured Evidence-Based Review Pain Medicine 2003 4 1 51 62 10.1046/j.1526-4637.2003.03008.x 12873278 Fishbain DA Lewis J Cole B Cutler B Smets E Rosomoff H Rosomoff RS Multidisciplinary Pain Facility Treatment Outcome for Pain-Associated Fatigue Pain Medicine 2005 6 4 299 304 10.1111/j.1526-4637.2005.00044.x 16083460 Fisher K Laikin AM Sharp KMH Criddle CA Palermo TM Karlson CW Temporal relationship between daily pain and actigraphy sleep patterns in pediatric sickle cell disease Journal of Behavioral Medicine 2018 41 3 416 422 10.1007/s10865-018-9918-7 29532199 Gil KM Porter L Ready J Workman E Sedway J Anthony KK Pain in Children and Adolescents With Sickle Cell Disease: An Analysis of Daily Pain Diaries Children’s Health Care 2000 29 4 225 241 10.1207/S15326888CHC2904_1 Harirforoosh S Asghar W Jamali F Adverse effects of nonsteroidal antiinflammatory drugs: An update of gastrointestinal, cardiovascular and renal complications Journal of Pharmacy & Pharmaceutical Sciences 2013 16 5 821 847 10.18433/j3vw2f 24393558 Hossain JL Ahmad P Reinish LW Kayumov L Hossain NK Shapiro CM Subjective fatigue and subjective sleepiness: Two independent consequences of sleep disorders? Journal of Sleep Research 2005 14 3 245 253 10.1111/j.1365-2869.2005.00466.x 16120099 Karlson, C. W., Leist-Haynes, S., Smith, M., Faith, M. A., Elkin, T. D., & Megason, G. (2012). Examination of risk and resiliency in a pediatric sickle cell disease population using the Psychosocial Assessment Tool 2.0. Journal of pediatric psychology, 37(9), 10.1093/jpepsy/jss087 Klimas NG Broderick G Fletcher MA Biomarkers for chronic fatigue Brain Behavior and Immunity 2012 26 8 1202 1210 10.1016/j.bbi.2012.06.006 22732129 Kovacs, M., & Staff, M. H. S. (2003). Children’s Depression Inventory (CDI): Technical Manual Update. North Tonawanda, NY: Multi-Health Systems. Inc b31 Onen SH Onen F Courpron P Dubray C How pain and analgesics disturb sleep The Clinical Journal of Pain 2005 21 5 422 431 10.1097/01.ajp.0000129757.31856.f7 16093748 Poku BA Caress AL Kirk S “Body as a machine”: How adolescents with sickle cell disease construct their fatigue experiences Qualitative Health Research 2020 30 9 1431 1444 10.1177/1049732320916464 32406309 Ream E Gibson F Edwards J Seption B Mulhall A Richardson A Experience of Fatigue in Adolescents Living With Cancer Cancer Nursing 2006 29 4 317 326 10.1097/00002820-200607000-00011 16871100 Rees DC Williams TN Gladwin MT Sickle-cell disease The Lancet 2010 376 9757 2018 2031 10.1016/S0140-6736(10)61029-X Reinman, L. (2019). Risk and resistance factors for depression and anxiety among youth with sickle cell disease (Doctoral dissertation). https://scholarcommons.sc.edu/etd/5438/ Rogers V Lance E Sleep, fatigue and neurodevelopmental outcomes in pediatric sickle cell disease Austin Pediatr 2017 4 2 1056 Rosen CL Debaun MR Strunk RC Redline S Seicean S Craven DI Gavlak JC Wilkey O Inusa B Roberts I Goodpaster RL Malow B Rodeghier M Kirkham FJ Obstructive sleep apnea and sickle cell anemia Pediatrics 2014 134 2 273 281 10.1542/peds.2013-4223 25022740 Schatz J Schlenz A McClellan CB Puffer ES Hardy S Pfeiffer M Roberts CW Changes in coping, pain and activity following cognitive-behavioral training: A randomized clinical trial for pediatric sickle cell disease using smartphones The Clinical journal of pain 2015 31 6 536 10.1097/AJP.0000000000000183 25503599 Schlenz AM Schatz J Roberts CW Examining Biopsychosocial Factors in Relation to Multiple Pain Features in Pediatric Sickle Cell Disease Journal of Pediatric Psychology 2016 41 8 930 940 10.1093/jpepsy/jsw003 26869665 Schwartz AL Daily fatigue patterns and effect of exercise in women with breast cancer Cancer practice 2000 8 1 16 24 10.1046/j.1523-5394.2000.81003.x 10732535 Stinson J Naser B Pain management in children with sickle cell disease Pediatric Drugs 2003 5 4 229 241 10.2165/00128072-200305040-00003 12662119 Valrie CR Gil KM Redding-Lallinger R Daeschner C Brief Report: Sleep in Children with Sickle Cell Disease: An Analysis of Daily Diaries Utilizing Multilevel Models Journal of Pediatric Psychology 2007 32 7 857 861 10.1093/jpepsy/jsm016 17400602 Valrie CR Gil KM Redding-Lallinger R Daeschner C Brief Report: Daily Mood as a Mediator or Moderator of the Pain-Sleep Relationship in Children with Sickle Cell Disease Journal of Pediatric Psychology 2007 33 3 317 322 10.1093/jpepsy/jsm058 17690117 Valrie CR Kilpatrick RL Alston K Trout K Redding-Lallinger R Sisler I Fuh B Investigating the Sleep–Pain Relationship in Youth with Sickle Cell Utilizing mHealth Technology Journal of Pediatric Psychology 2019 44 3 323 332 10.1093/jpepsy/jsy105 30649539 Watson, D., Clark, L. A., & Tellegen, A. (1988).Development and Validation of Brief Measures of Positive and Negative Affect: The PANAS Scales.Journal of Personality and Social Psychology, 54(6),1063–1070. 10.1037//0022-3514.54.6.1063 While AE Mullen J Living with sickle cell disease: the perspective of young people British Journal of Nursing 2004 13 6 320 325 10.12968/bjon.2004.13.6.12528 15126965 Wong DL Baker CM Pain in children: Comparison of assessment scales Pediatric Nursing 1988 14 1 9 17 3344163 Zempsky WT Palermo TM Corsi JM Lewandowski AS Zhou C Casella JF Daily Changes in Pain, Mood and Physical Function in Youth Hospitalized for Sickle Cell Disease Pain Pain Research and Management 2013 18 1 33 38 10.1155/2013/487060 23457684
PMC009xxxxxx/PMC9646888.txt	==== Front Urologia Urologia URJ spurj Urologia 0391-5603 1724-6075 SAGE Publications Sage UK: London, England 36346172 10.1177/03915603221136321 10.1177_03915603221136321 Original Articles Infections and Covid-19 Emergency Urology procedures during the COVID-19 pandemic in the UK: A 3-month prospective study https://orcid.org/0000-0002-8523-306X Georgiou Marita Ridzuan-Allen Adam Chamsin Alaa Siddiqui Zain Tolofari Sotonye Ejikeme Chidozie Jones Richard https://orcid.org/0000-0002-7696-7512 Napier-Hemy Timothy P Rotas Stefanos Hughes Kaylie E Khattak Altaf Q McCabe John E Omar Ahmad M Mistry Rahul Samsudin Azizan Gana Hosea BY Floyd Michael S Jr. Department of Urology, St Helens and Knowsley NHS Trust, Whiston Hospital, Prescot, Merseyside, UK Marita Georgiou, Department of Urology, St Helens and Knowsley NHS Trust, Whiston Hospital, Prescot L35 5DR, Merseyside, UK. Email: [email protected] 8 11 2022 5 2023 8 11 2022 90 2 407414 27 8 2021 11 10 2022 © The Author(s) 2022 2022 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. Objective: COVID-19 resulted in Regional tiered restrictions being introduced across the UK with subsequent implications for planned and emergency surgical care. Specific to Merseyside, Tier 4, Tier 2 and Tier 5 restrictions were introduced in late 2020 and early 2021. The purpose of this study was to examine the nature and workload of emergency urological procedures during three different national lockdown Tiers in the North West of England. Method: A 3-month prospective study examining all emergency urological activity was conducted from November 2020 when Tier 4 restrictions were introduced and included Tier 2 restrictions in December and then concluded at the end of January 2021 when Tier 5 restrictions were in place. Data was obtained by identifying patients using the electronic theatre listing system. Results: A total of 71 emergency cases were performed (24 in November (Tier 4), 28 in December (Tier 2), 19 in January 2021 (Tier 5)) with 15 different types of procedures performed. The most frequently performed procedure was stent insertion (36), followed by scrotal exploration (10). The least commonly performed procedure was suprapubic catheter insertion under general anaesthesia (1). One patient required transfer to a different hospital. In total 6 calls were made by general surgery and 3 by gynaecology for urgent urological assistance in theatre. Three urology patients returned to the theatre as emergencies following elective procedures. Conclusion: Unlike the Spring lockdown, acute urological presentations requiring operative intervention still presented daily. Of the 71 cases performed, most occurred in Tier 2. Stent insertion was the most commonly performed procedure, with the majority of the cases performed by registrars. COVID-19 pandemic emergency urology procedures typesetterts1 ==== Body pmcIntroduction The World Health Organization (WHO) formally announced in early 2020 an outbreak of a respiratory virus in Wuhan, China, was caused by named COVID-19. 1 In March 2020, a pandemic was declared by the WHO due to the spread of the Coronavirus involving more than 118,000 cases and 4000 deaths in 114 countries. 2 In the UK, a national lockdown was announced in March 2020. 3 The Government ordered citizens to work from home and placed limitations on social contacts to prevent the National Health Service from becoming overwhelmed. 3 During the first wave of the COVID-19 pandemic in the North West of England, the exponential rise of cases placed the region at the top of the leader board, following London. 4 A significant decrease in elective and emergency surgical cases was registered in different countries.2,5,6 As a result, duties were distributed to all hospital specialities to cope with the growing demand for patients with COVID-19.6,7 The resultant demands placed on Intensive care, nursing and Anaesthetic capacity led to a lack of availability of staff for elective surgical work. COVID-19 affected all aspects of surgical care, from outpatient consultation to non-emergency surgery and diagnostics.7–9 The pandemic affected urological practice, ranging from treatments provided to patients to the teaching opportunities available to trainees.7–10 For acutely hospitalised non-COVID-19 patients, the aim was prompt, safe discharge as per British Association of Urological Surgeons (BAUS) recommendations. 9 Alterations included the earlier discharge of patients with urosepsis once parameters improved rather than proceeding with observation for 24 h. 9 During the initial lockdown, all routine appointments and diagnostic procedures were postponed and new methods of consultation were applied, that is, telephone or virtual consultations.7,9–11 BAUS published alternative approaches for managing cancer.9,12 For major uro-oncological procedures, new modifications were applied in order to maintain the continuous provision of surgical services.4,13 Procedures such as cystoscopy, prostatic biopsies, and intravesical therapy for low or intermediate tumours were postponed.7,14 Uro-oncology services adapted quickly. Cognisant of the medico-legal implications of late diagnoses, specifically for malignancies like bladder cancer, units developed an electronic register that proved invaluable in detecting surveillance delays. 15 Non-urgent stone procedures such as ESWL were deferred.11,16 Emergency surgical cases were permitted with guidelines issued to avoid laparoscopic procedures.4,7–9,17 The decision of which operative intervention to perform remained the responsibility of the Consultant Urologist. During the First wave, the decision was made by the department chair or committee of the surgical division. 8 Some hospitals applied specific COVID-19 Urology surgical Triage Algorithms, 5 or priority groups as per NHS England guidance (Level I-IV)4,12 The Cleveland Clinic recommended a 4 Tier classification. 9 Non-invasive procedures such as ESWL for acute stone presentations or nephrostomy insertion for acutely obstructed kidneys were recommended if available.7,18 Although the first wave of the COVID-19 eased, the second surge in the Autumn developed quickly. 19 As the pandemic progressed, regional Tiered restrictions were introduced. 19 Specific to the North West UK, three different Tiers were applied between November 2020 and January 2021 (Table 1). This resulted in varying levels of permissible social mobility with specific implications for the hospitality industry and retail. Specific to our Trust, there was a drive to continue some elective surgical work with all oncological cases remaining a priority. Elective reconstruction and core work were curtailed in January 2021, due to a lack of theatre staff as they had been (a) redeployed or (b) ill with COVID-19. As the study progressed, we noticed that patients continued to regularly present with non-COVID-19 related emergencies. Table 1. Tiered restrictions. Tier 2 – Medium Alert Meeting with others: can meet with people from different household, up to 6 people Travel and transport: No restrictions Work: Work from home where possible Shops: Open Hospitality: Open until 11pm Tier 3 – High Alert Meeting with others: can meet with people from different household, up to 6 people Travel and transport: Limited where possible Work: Work from home where possible Shops: Open Hospitality: Table service only, close by 11pm, maximum group of 6 people Tier 4 – Very High Alert Meeting with others: To stay in house with people you live with. Travel and transport: Minimised Work: Work from home where possible Shops: Open Hospitality: Closed Tier 5 – Stay at home Meeting with others: Stay at home Travel and transport: Essential Work: Work from home where possible Shops: Closed Hospitality: Closed Methods A 3-month prospective study examining all emergency Urology procedures was performed by the Department of Urology in Whiston Hospital, Merseyside. The study’s primary aim was to determine the volume and nature of emergency work performed by the department of Urology during three different tiers of the pandemic between November 2020 and January 2021 (Table 1). A secondary aim was to determine if the national message of ‘Stay at home and protect the NHS’ still resulted in decreased emergency presentations to a large urology unit in North West of England during tiered restrictions as during the initial wave, emergency activity reduced significantly. A third aim was to examine the grade of the practitioner performing the procedure. Training opportunities had been severely affected by the mandatory reductions in elective theatre activity during the first wave and we were eager to record the exposure of trainees to emergency work when tiered restrictions were in place. Data was obtained daily using the electronic theatre listing system with additional input from the urological registrars collected during their on-calls. All patients requiring emergency urological procedures following an acute admission under urology were included. Additionally, acute presentations that required transfer to other Hospitals for ITU management were included. Referrals made to the urology team for urgent intraoperative assistance from the general surgical, obstetrical or gynaecology teams were recorded. Urgent one-off non-invasive procedures, such as ESWL (Extracorporeal Shock Wave Lithotripsy) were also included and selected catheter-related issues that required General anaesthetic input. Any patient that returned to theatre on an emergency basis following an elective procedure was also included. Grade of operator was also recorded in all cases. A data base was maintained during the 3-month study, which was updated and analysed on a daily basis by the study lead with the above details recorded. Results A total of 71 procedures were carried out over three different phases of national restrictions introduced in response to the changing regional levels of COVID-19 between November 2020 and January 2021 (Figure 1). Detailed analysis revealed that 15 different procedures were undertaken during the second wave of the COVID-19 pandemic with the regional Tier system restrictions in place (Figure 2). Figure 1. Volume of procedures performed during the three different Tiers (2020–2021). Figure 2. All procedures performed during the three different Tiers (2020–2021). During the first month of the study (November 2020) 24 cases were performed during level 4 restrictions. An increase in procedures performed was noticed when the Tier 4 restrictions eased in December 2020 to Tier 2 with 28 cases performed and a significant drop in cases was observed when national lockdown was introduced in January 2021 (Tier 5) with only 19 cases performed (Figures 1 and 2). The commonest procedure performed was stent insertion (36, 51%), followed by scrotal exploration (10, 14%) across all three tiers. The general surgical team required urological input on six occasions (9%) and the gynaecology team on three occasions (4%). Over half of the procedures were performed by the specialist registrars unsupervised (44, 62%), while 10 procedures were performed by Consultants (Figure 3). Figure 3. Grade of operator. The monthly breakdown revealed that in November 2020 when Tier 4 restrictions were in place a total of 24 procedures were undertaken (Figures 1 and 2). In November, eight different procedures were performed, with stent insertion being the commonest (12, 50%), followed by scrotal exploration (4, 17%). The urology team was called for assistance from the general surgical team twice and once from the gynaecology team. One patient returned to theatre following an elective Burch Colposuspension. A single patient required inpatient Extracorporeal Shock Wave Lithotripsy (ESWL), which was in operation in the Trust during Tier 4 restrictions in a very limited capacity, led by urology nurse specialists. Half of the procedures were performed by specialist registrars independently, while Consultants supervised five of the specialist registrars’ procedures. In only four cases, the Consultant performed the emergency procedure. Detailed analysis of December 2020 when Tier 2 restrictions were introduced in Merseyside, 20 revealed that 28 emergency procedures were performed that month. Ten different procedures took place, of which stent insertion was again the most frequently performed procedure (14, 50%), followed by scrotal exploration (3, 11%). Urological input was required twice from the general surgical team and once from the gynaecology team. One patient required an immediate return to theatre for suspected post-operative bleeding following an elective Burch Colposuspension. One patient required urgent transfer to a different hospital for ITU and dialysis management. Half of the procedures (14, 50%) were performed by specialist registrars without supervision, and in four cases, there was a supervising Consultant present. On six occasions, direct involvement of the Consultant Urologist was required. A national lockdown was introduced in January 2021 as ‘alert level 5’ in response to a significant increase in COVID-19 cases following the Christmas Holiday period. 21 It was advised that citizens stay and work from home if possible, schools were closed, and people were only allowed to leave the house for basic necessities or medical assistance. 21 In total, 19 emergency urological procedures were performed during January 2021 during the imposed national lockdown (Tier 5). Detailed analysis demonstrated that only seven different procedures were performed. Stent insertion was again the procedure most frequently performed (10, 53%), followed by scrotal exploration (3, 16%). Three calls were made to the urology team for assistance: two from the general surgical team and one from the gynaecology team. Two bladder washouts under general anaesthesia occurred. One patient required urgent suprapubic catheter insertion under general anaesthesia due to a dislodged catheter and pain concerns with previous catheter placement under local anaesthesia. Three urgent catheter placements performed by the urology team for different medical teams were recorded during the study. Although lockdown prevented face-to-face consultations in primary care20,21 and limited social interactions outside permitted family bubbles, during the 3-month study there were no Fournier’s gangrene or penile fracture cases. Additionally, due to the national restrictions on team sport no sport related Urogenital injuries presented. One trauma case did present during the 3 months: a scrotal laceration which required suturing. Overall, out of 71 procedures performed stent insertion and emergency scrotal exploration remained the two most frequently performed procedures during the three different Tiers of lock down with 36 stents inserted and 10 scrotal explorations recorded. The four least commonly performed procedures were suprapubic catheter insertion under general anaesthesia (1), urgent ESWL (1), stent removal (1) and reduction of paraphimosis (1). Specialist registrars performed a total of 62% of cases without supervision and 14% of cases were performed by Consultants in a supervisory or training capacity with a registrar. Therefore, trainees were involved in 76% of all emergency cases. Only 14% of call cases were performed by Consultants with no trainees. Discussion The emergence of the COVID-19 pandemic in the Spring of 2020 brought unprecedented changes to all facets of healthcare delivery across the globe. Specific to the UK, the initial lockdown led to a cessation of elective surgical work as citizens adopted the mantra of ‘Stay at Home and Protect the NHS’. In Tandem, outpatient services and diagnostics ceased, emergency procedures and presentations diminished and new modifications and realignment of the services were applied as per the new COVID-19 restrictions and guidelines.7,9,11,22 Diagnostic measures such as cystoscopy were postponed.14,23,24 Application of safety measures were applied to avoid the spread of COVID-19 cases. 25 Consequently, new cancer diagnoses and other pathologies requiring surgical intervention were limited. As COVID-19 developed, the associated effects of delayed services were apparent and new guidelines were introduced as Government directions changed and encouraged citizens to use the NHS if unwell for all conditions. Additionally, BAUS published new recommendations for the re-introduction of procedures, especially in the more vulnerable patient groups emphasising the need for continuous risk assessment. 24 Moreover, new efforts were put in place for the reinstatement of elective services. 9 Separately the pandemic led to a rapid increase in the published literature devoted to the effects of COVID-19 on many aspects of urological practice, including service delivery, recommendations for ongoing uro-oncological care provision and innovative ideas for patient care that emerged during the crisis .2,4–8,13,15,16,26 As elective surgical activity reduced, this had major implications for ongoing surgical training. Several papers have commented on the impact of the COVID-19 pandemic on trainees and indicative training numbers.10,27 Nevertheless, new approaches were developed to maximise teaching opportunities through webinars,10,13,27 virtual journal clubs and on-line lectures. 27 Some face-to-face meetings were replaced with videoconferences.10,27 Additionally, all professional examinations and courses were postponed. 10 In our Trust stringent efforts were made to continue all uro-oncological and semi elective benign work. In Tandem, emergencies continued to present that require urgent operative management. One of the innovative ideas developed in our trust was a risk stratification system for procedures. A Prioritisation system (P1–P5) was devised and utilised at time of listing a patient for a Urological procedure. New listing sheets were printed to reflect this new classification. Urgent time sensitive procedures such as radical orchidectomy were stratified as P1 implying surgery required within 2–3 weeks. Procedures such as vasectomy or excision of scrotal skin lesions were classified as P5 resulting in surgery within 3–4 months. Specific to this study we aimed to examine the volume of emergency urological procedures performed over 3 months and to examine in detail who performed them. This study has shown that despite Tiered restrictions introduced during the second wave of the COVID-19 pandemic, emergency urological procedures continued as required for acutely admitted cases. During Tier 4 and Tier 5 restrictions, there was a noticeable decrease in emergency urological cases, especially during the national lockdown in January 2021. In December 2020, when restrictions eased to a Tier 2 restriction the volume and the nature of procedures increased with nine additional procedures performed in Tier 2 compared to Tier 5. However, acute urological presentations requiring surgical intervention still occurred despite local and national restrictions, unlike the first lockdown in March 2020. Gallioli et al. during the first lockdown in Italy, reported that emergency urological admissions were remarkably reduced in comparison with the admissions the year before the COVID-19 pandemic. 28 Regarding non-surgical specialities: although there was a significant increase in patients admitted with a ‘Respiratory diagnosis’, 28 specific medical conditions such as Acute Exacerbation of COPD (AECOPD) were reduced in both periods of lockdown during the COVID-19 pandemic. 29 Unsurprisingly, during the second wave, there was an increase in admissions in comparison with the first wave but not as pronounced as the pre-COVID data. 29 Italy was markedly affected during the COVID-19 pandemic and was the first European Country to implement measures to avoid a further increase in cases. 30 The same considerations applied to Urology as a speciality regarding the treatment of uro-oncology patients.28,31 Systems and guidelines were installed for patients with Non-Muscle Invasive Bladder Cancer (NMIBC).28,31,32 Cancer-risk assessment and factors for perioperative complications associated with the ‘immunocompromised cancer-related state’ were considered with COVID-19. 33 However, a delay in delivery of cancer care was noted, by means of reduced numbers of transurethral resections (TURBT) performed.28,31,32 ESWL is recommended by both the American Urological Association/Endourological Association and European Association of Urology as an effective alternative method for ureteral stones as it avoids general anaesthesia7,16 During this study, it was utilised only once. This was a reflection of the fact that during the pandemic, many nurse specialists (performing ESWL) were redeployed to COVID-19 wards or ITU in our Trust. From a training perspective, most of the procedures were performed by specialist registrars with 76% of all emergency cases recorded as having registrar involvement. Procedures performed by senior house officers under supervision were minimal; 4 (6%) under the supervision of a specialist registrar and 1 (1%) unsupervised. The COVID-19 pandemic had a negative effect on training for core surgical trainees in urology.10,27 Moreover, in a separate survey assessing the effects of the first wave of COVID-19 on specialist urological training, results showed decreased surgical exposure and that ‘Consultant only’ was preferred in the operating theatre, especially over the peak of COVID-19 cases during the first lockdown.10,13 In a different study conducted during the first wave of the COVID-19 pandemic similar findings were reported; core trainees were predominantly negatively affected by decreased theatre exposure and reduced experience in outpatient settings. 10 The senior trainees were more likely to be allocated theatre time due to experience in order to reduce operating time.9,10,16 Specific to this study, we have shown that specialist registrars carried out most emergency procedures and this is an important finding from this study. This study has some limitations. Firstly, only patients requiring emergency urological procedures were included and there was no record of all the urological patients needing admission during this period, such as those presenting with orchitis, pyelonephritis or retention. Another limitation is that an accurate comparison of the rate of emergency procedures during the second period of regional lockdown restrictions to that experienced in the first wave in Spring 2020 was not performed as this study aimed to deal with the emergency procedures performed during the second wave only. Regrettably, we did not record ‘wait times’ for urology emergencies in accessing the emergency department of our hospital compared to the first wave or in the non-pandemic era, which is another limitation of this study. Admittedly, the complexity of the urgent procedures performed is also minimal as stent insertion and scrotal exploration remained the two most commonly performed procedures during the 3-month study. This study was conducted over a short period of time when the Tiered restrictions were implemented and as a result a small cohort of patients were included and this is a major limitation of this study. The reduction of social interaction and cessation of team sports as alluded to earlier meant that less frequent emergency cases such as Fournier’s gangrene and penile fracture did not feature during the period studied. A separate study is planned to looked at post pandemic recovery in urology. Conclusion This 3-month study has demonstrated the impact of the Tiered restriction system on the emergency urological procedures performed in a large UK Hospital. A total of 71 cases were performed, with more occurring in Tier 2. Increased restrictions had a definite impact on emergency case presentations. We have further demonstrated as a result of this work that (a) unlike the Spring lockdown emergency cases requiring surgery still presented and (b) trainees continued to have exposure to emergency operations during the pandemic with Consultant supervision. The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article. ORCID iDs: Marita Georgiou https://orcid.org/0000-0002-8523-306X Timothy P Napier-Hemy https://orcid.org/0000-0002-7696-7512 ==== Refs References 1 WHO. Timeline: WHO COVID-19 response, https://www.who.int/emergencies/diseases/novel-coronavirus-2019/interactive-timeline# (2020, accessed 27 February 2021). 2 Temiz MZ Yuruk E Kandirali E , et al . The urological practice and contribution to the general health system of the EBU accredited urology clinic during the first month of COVID-19 pandemic: an analysis from a tertiary center declared as a national COVID-19 pandemic hospital in Turkey. Turk J Urol 2021; 47 (1 ): 43–50.33052838 3 GOV.UK. Prime Minister’s statement on COVID-19, https://www.gov.uk/government/speeches/pm-address-to-the-nation-on-coronavirus-23-march-2020 (2020, accessed 27 February 2021). 4 Shillito S O’Flynn K Clarke N , et al . Maintaining a safe uro-oncological surgical service in the face of the COVID-19 pandemic. J Clin Urol 2021; 14 : 404–409. 5 Pak JS Sayegh CI Smigelski MB , et al . A Urology Department’s experience at the epicenter of the COVID-19 pandemic. Urology 2020; 144 : 4–8.32619601 6 Ficarra V Novara G Abrate A , et al . Urology practice during the COVID-19 pandemic. Minerva Urol Nefrol 2020; 72 (3 ): 369–375.32202401 7 Mazzucchi E Torricelli FCM Vicentini FC , et al . The impact of COVID-19 in medical practice. A review focused on Urology. Int Braz J Urol 2021; 47 : 251–262.32840335 8 Gravas S Bolton D Gomez R , et al . Impact of COVID-19 on urology practice: a global perspective and snapshot analysis. J Clin Med 2020; 9 : 1730.32503305 9 Fonseka T Ellis R Salem H. A critical review of urological practice during the coronavirus disease 2019 pandemic and the emerging role of telemedicine. J Clin Urol 2020; 14 (3 ): 166–174. 10 Carrera A Shin JS Bekarma H. Impact of the COVID-19 pandemic urology trainees in the West of Scotland. J Clin Urol 2021; 14 (6 ): 481–486. 11 Somani BK Pietropaolo A Coulter P , et al . Delivery of urological services (telemedicine and urgent surgery) during COVID-19 lockdown: experience and lessons learnt from a university hospital in United Kingdom. Scott Med J 2020; 65 (4 ): 109–111.32819219 12 The British Association of Urological Surgeons. BAUS guidelines for planning non-emergency operating services in the COVID-19 era, https://www.baus.org.uk/ (2020, accessed 17 March 2021). 13 Folkard SS Sturch P Mahesan T , et al . Effect of coronavirus disease 2019 on urological surgery services and training up to the peak of the pandemic in South East England. J Clin Urol 2021; 14 : 47–54. 14 Esperto F Papalia R Autrán-Gómez AM , et al . COVID-19’s impact on Italian urology. Int Braz J Urol 2020; 46 (suppl.1 ): 26–33. 15 O’Meara S Byrnes K Nic An Ríogh A , et al . The use of an automated electronic registry for bladder cancer surveillance during the SARS-CoV-2 pandemic. J Clin Urol 2022; 15 : 424–428. 16 Fakhr Yasseri A Aghamir SMK . Urinary stone management during the COVID-19 pandemic: a suggested approach and review of literature. Ther Adv Urol 2020; 12 : 1–5. 17 The British Association of Urological Surgeons. BAUS guidance on urological laparoscopy and robotic-assisted laparoscopic surgery during the COVID-19 pandemic, https://www.baus.org.uk/default.aspx (2020, accessed 17 March 2021). 18 The British Association of Urological Surgeons. BAUS COVID-19 Re-introduction prioritisation BAUS section of endourology, https://www.baus.org.uk/default.aspx (2020, accessed 17 March 2021). 19 GOV.UK. Details on local COVID alert levels, https://www.gov.uk/government/news/prime-minister-announces-new-local-covid-alert-levels (2020, accessed 27 February 2021). 20 GOV.UK. Review on local restriction tiers, https://www.gov.uk/government/speeches/review-of-local-restriction-tiers-17-december-2020 (2020, accessed 29 February 2021). 21 GOV.UK. Prime Minister’s address to the nation, https://www.gov.uk/government/speeches/prime-ministers-address-to-the-nation-4-january-2021 (2021, accessed 29 February 2021). 22 The British Association of Urological Surgeons. BAUS plans for COVID -19 recovery/plateau phase. Section of andrology & genito-urethral surgery, https://www.baus.org.uk/default.aspx (2020, accessed 17 March 2021). 23 The British Association of Urological Surgeons. BAUS COVID-19 bladder cancer contingency plan prepared by the BAUS section of oncology, https://www.baus.org.uk/default.aspx (2020, accessed 17 March 2021). 24 The British Association of Urological Surgeons. BAUS steering guidelines for the safe re-introduction of urological surgery and activity FNUU section of BAU. Version 1, https://www.baus.org.uk/default.aspx (2020, accessed 17 March 2021). 25 Antonio Maria G Vasileios P Giacomo Piero I , et al . Urologic surgery and invasive procedures during coronavirus pandemic: retrospective comparison of risk infection in a referral Covid hospital and in a free-Covid hospital. Urol J 2020; 87 (4 ): 163–166. 26 Jain A Croghan SM Kelly C , et al . The early impact of COVID-19 on urological service provision. Ir Med J 2020; 113 (8 ): 157.33730472 27 Fonseka T Ellis R Salem H , et al . The effects of COVID-19 on training within urology: Lessons learned in virtual learning, human factors, non-technical skills and reflective practice. J Clin Urol 2021; 14 : 29–35. 28 Gallioli A Albo G Lievore E , et al . How the COVID-19 wave changed emergency urology: results from an academic tertiary referral hospital in the epicentre of the italian red zone. Urology 2021; 147 : 43–49.33010292 29 Lawless M Burgess M Bourke S. Impact of COVID-19 on hospital admissions for COPD exacerbation: lessons for future care. Medicina 2022; 58 (1 ): 66.35056374 30 Maccagnano C Conti GN Ferro M , et al . Emergency room access during pandemic: can urologist learn something from the covid-19? An Italian experience. Arch Clin ExpSurg 2020; 9 (1 ): 08–15. 31 Ferro M Del Giudice F Carrieri G , et al . The impact of SARS-CoV-2 pandemic on time to primary, secondary resection and adjuvant intravesical therapy in patients with high-risk non-muscle invasive bladder cancer: A retrospective multi-institutional cohort analysis. Cancers 2021; 13 : 5276.34771440 32 Paciotti M Contieri R Fasulo V , et al . Active surveillance for recurrent non-muscle invasive bladder cancer: which lessons have we learned during COVID-19 pandemic? Minerva Urol Nephrol 2022; 74 (1 ): 1–4.34338493 33 Maccagnano C Rocchini L Montanari E , et al . Overview of the Italian experience in surgical management of bladder cancer during first month of COVID-19 pandemic. Arch Ital Urol Androl 2020; 92 (4 ): 275–281.
PMC009xxxxxx/PMC9673185.txt	==== Front Curr Probl Diagn Radiol Curr Probl Diagn Radiol Current Problems in Diagnostic Radiology 0363-0188 1535-6302 Elsevier Inc. S0363-0188(22)00144-X 10.1067/j.cpradiol.2022.11.001 Article Trends in coronary calcium score and coronary CT angiography imaging volume during the COVID-19 pandemic An Thomas J. MD abc Kim Nicole BA abc King Alexander H. MS abc Panzarini Bruno MD abc Little Brent P. MD ab Goiffon Reece J. MD ab Meyersohn Nandini MD ab Garrana Sherief MD ab Stowell Justin MD ab Saini Sanjay MD abc Ghoshhajra Brian B. MD, MBA ab Hedgire Sandeep MD ab Succi Marc D. MD abc⁎ a Harvard Medical School, Boston, MA b Department of Radiology, Massachusetts General Hospital, Boston, MA c Medically Engineered Solutions in Healthcare Incubator, Innovation in Operations Research Center (MESH IO), Massachusetts General Hospital, Boston, MA ⁎ Reprint request: Marc D. Succi, MD, Department of Radiology, Massachusetts General Hospital, 55 Fruit St, Boston, MA 02114. 18 11 2022 May-June 2023 18 11 2022 52 3 175179 © 2022 Elsevier Inc. All rights reserved. 2022 Elsevier Inc. Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Objectives The COVID-19 pandemic disrupted the delivery of preventative care and management of acute diseases. This study assesses the effect of the COVID-19 pandemic on coronary calcium score and coronary CT angiography imaging volume. Materials and methods A single institution retrospective review of consecutive patients presenting for coronary calcium score or coronary CT angiography examinations between January 1, 2020 to January 4, 2022 was performed. The weekly volume of calcium score and coronary CT angiogram exams were compared. Results In total, 1,817 coronary calcium score CT and 5,895 coronary CT angiogram examinations were performed. The average weekly volume of coronary CTA and coronary calcium score CT exams decreased by up to 83% and 100%, respectively, during the COVID-19 peak period compared to baseline (P < 0.0001). The post-COVID recovery through 2020 saw weekly coronary CTA volumes rebound to 86% of baseline (P = 0.024), while coronary calcium score CT volumes remained muted at only a 53% recovery (P < 0.001). In 2021, coronary CTA imaging eclipsed pre-COVID rates (P = 0.012), however coronary calcium score CT volume only reached 67% of baseline (P < 0.001). Conclusions A significant decrease in both coronary CTA and coronary calcium score CT volume occurred during the peak-COVID-19 period. In 2020 and 2021, coronary CTA imaging eventually superseded baseline rates, while coronary calcium score CT volumes only reached two thirds of baseline. These findings highlight the importance of resumption of screening exams and should prompt clinicians to be aware of potential undertreatment of patients with coronary artery disease. ==== Body pmcIntroduction The disruptive effects of the COVID-19 pandemic have caused significant operational challenges for healthcare systems. As COVID-19 cases peaked in 2020, hospitals faced unprecedented demands related to shortages in healthcare workers, hospital beds, and equipment. While significant hospital resources were diverted towards treatment of patients with COVID-19, healthcare access and utilization were disrupted for many patients with chronic diseases or other healthcare needs. As many emergency departments were overwhelmed by patients with COVID-19 and outpatient appointments were postponed or cancelled, delivery of preventative care and management of both acute and chronic diseases has been suboptimal.1, 2, 3 National surveillance data revealed a significant decline in emergency department utilization, including for acute myocardial infarction and stroke, during the initial months of the pandemic.4 In addition, emerging data is beginning to show concerning trends in the wholescale reduction of diagnostic health examinations, including low dose screening chest CT for lung cancer and diagnostic testing for cardiovascular disease.5, 6, 7 In the setting of cardiovascular screening, coronary calcium score CT has an important preventative role in assessing risk for cardiovascular disease in low and intermediate risk asymptomatic patients.8, 9, 10, 11, 12, 13 Similarly, coronary CT angiography (CTA) is an important non-invasive examination for assessment of the coronary arteries in symptomatic patients with both stable chest pain and acute chest pain at low-to-intermediate risk of acute coronary syndrome.14, 15, 16, 17 The aim of this study was to evaluate how coronary calcium score CT and coronary CTA volumes were affected by the COVID-19 pandemic and analyze the subsequent recovery in exam volumes. Materials and methods Study setting A single institution retrospective review was performed in compliance with the Health Insurance Portability and Accountability Act and approved with exemption by the Massachusetts General Hospital Institutional Review Board. Data for all coronary CTA and coronary calcium score CT exams performed at our academic medical center were extracted from the electronic medical record for the period January 1, 2020-January 4, 2022. Our institution is a 1063-bed quaternary care urban academic medical center in Massachusetts treating approximately 50,000 inpatients, 98,000 ED patients, and 775,000 outpatients annually.18 Analysis Four time periods were defined in this study: a pre-COVID baseline period from January 1, 2020 to March 10, 2020; a COVID-19 peak period from March 11, 2020 to May 2, 2020; a 2020 recovery period from May 3, 2020 to January 4, 2021; and a 2021 recovery period from January 5, 2021 to January 4, 2022. The start of the “COVID-19 peak” period was defined as the declaration of a State of Emergency related to COVID-19 in the state of Massachusetts on March 10, 2020.19 During the subsequent weeks, a series of measures intended to reduce the transmission of COVID-19 were implemented, including drastic reductions in elective care and imaging. The radiology department at our institution implemented measures in accordance with hospital policies and governmental guidelines, including reduction of daily outpatient imaging slots by 50% and elimination of weekend outpatient cardiac CT imaging. Data for coronary CTA and coronary calcium score CT exams were grouped in 1-week intervals. Coronary CTAs had been assigned scores defined by the Coronary Artery Disease – Reporting and Data System (CAD-RADS) consensus document.20 Calcium scores (CACS) had been calculated by the Agatston scoring method and classified as “no evidence of CAD” (CACS = 0), “minimal” (0 < CACS <10), “mild” (10 < CACS < 100), “moderate” (100 < CACS < 400), and “severe” (CACS > 400).21 Baseline rates are the average of the weekly imaging volumes during the pre-COVID-19 baseline period. Data analysis was performed using R version 3.6.1.22 CAD-RADS 3, 4a, 4b, and 5 were grouped as a “Significant Stenoses Group” – clinically significant stenoses that would prompt further testing and treatment including but not limited to: functional assessment, pharmacotherapy, and/or invasive coronary angiography.20 Results The average weekly volume of coronary CTA and coronary calcium score CT exams decreased by up to 83% and 100%, respectively, during the COVID-19 peak period compared to the pre-COVID peak period (Fig 1 A). Coronary CTA exam volume decreased from 58 ± 7 studies per week at baseline to 21 ± 14 studies during the COVID-19 peak period (P < 0.001) and coronary calcium score CT exam volume decreased from 28 ± 8 studies per week at baseline to 4 ± 8 during the COVID-19 peak period (P < 0.001). There was gradual recovery of both coronary CTA and coronary calcium score CT exam volumes during the post-COVID-19 peak period (Fig 1B). During the post-COVID-19 peak, mean coronary CTA exam volume reached approximately 84% of baseline in 2020 during the post-COVID-19 peak period (50 ± 10 vs 58 ± 7, P = 0.024) and 114% of baseline in 2021 (66 ± 9 vs 58 ± 7, P = 0.012). Coronary calcium score CT volume decreased by a relatively larger degree than coronary CTA volume and remained persistently muted throughout the post-COVID-19 peak period (Fig 1B). Mean coronary calcium score CT volume was approximately 52% of baseline in 2020 during the post-COVID-19 peak period (15 ± 8 vs 28 ± 8, P < 0.001) and 67% of baseline in 2021 (19 ± 6 vs 28 ± 8, P < 0.001) (Table 1 ).FIG 1 (A) is a graphical representation of the weekly number of coronary CTA and calcium score CT exams over time. The gray shaded box denotes the peak-COVID-19 period where the radiology department implemented measures in accordance with hospital policies and governmental guidelines to reduce imaging volume. (B) Demonstrates the weekly percent change from baseline in volume for both coronary CTA and calcium score CT. (Color version of figure is available online.) FIG 1 TABLE 1 Comparison of mean studies per week and scoring categories of coronary CTA and cardiac CT for calcium scoring during the peak COVID-19, and post-COVID 2020 and 2021 recovery periods compared to a pre-COVID baseline TABLE 1 Pre-COVID Baseline Peak-COVID P-value Post-COVID 2020 recovery P-value Post-COVID 2021 Recovery P-value Coronary CTA 57.6 ± 7.2 20.9 ± 14.0 <0.001 49.7 ± 10.0 0.024 65.7 ± 9.3 0.012 CAD-RADS 0 17.8 ± 4.9 6.5 ± 4.1 <0.001 14.6 ± 4.9 0.075 18.1 ± 4.5 0.832 CAD-RADS 1 12.5 ± 2.1 4.9 ± 3.1 <0.001 8.5 ± 3.2 <0.001 12.0 ± 3.8 0.708 CAD-RADS 2 14.0 ± 3.3 5.0 ± 3.4 <0.001 14.1 ± 4.7 0.958 18.7 ± 4.8 0.004 CAD-RADS 3 3.4 ± 1.5 1.3 ± 1.7 0.011 4.3 ± 1.9 0.186 6.5 ± 2.9 0.002 CAD-RADS 4A 5.7 ± 2.6 1.9 ± 1.6 0.002 5.3 ± 2.4 0.615 6.5 ± 3.0 0.440 CAD-RADS 4B 1.5 ± 1.3 0.4 ± 0.7 0.042 1.5 ± 1.1 0.972 1.7 ± 1.6 0.699 CAD-RADS 5 2.7 ± 1.5 1.0 ± 1.4 0.026 1.5 ± 1.1 0.008 2.1 ± 1.5 0.184 Significant Stenosis 13.3 ± 3.4 4.5 ± 4.5 <0.001 12.5 ± 3.5 0.528 16.8 ± 4.6 0.027 Cardiac CT 28.2 ± 7.6 3.8 ± 7.9 <0.001 14.9 ± 8.4 <0.001 18.9 ± 6.3 <0.001 No CAD (0) 9.0 ± 2.8 0.9 ± 1.8 <0.001 5.7 ± 3.8 0.014 7.2 ± 3.6 0.146 Minimal (1-10) 2.3 ± 1.8 0.4 ± 0.7 0.011 1.7 ± 1.5 0.255 2.3 ± 1.8 0.990 Mild (11-100) 6.4 ± 3.0 0.8 ± 1.4 <0.001 3.3 ± 2.4 0.001 4.2 ± 2.2 0.010 Moderate (101-400) 7.2 ± 2.9 1.4 ± 3.5 0.001 2.4 ± 2.1 <0.001 2.9 ± 1.9 <0.001 Severe (>400) 3.3 ± 2.5 0.4 ± 0.7 0.005 1.8 ± 1.5 0.023 2.3 ± 1.6 0.010 During the post-COVID-19 2020 and 2021 recovery periods, there was no statistically significant decrease in the volume of coronary CTA exams with clinically significant CAD-RADS 4A and 4B scores compared to baseline, even in the setting of decreased overall volume (Table 1, Fig 2 ). However, there were statistically significant decreases in absolute volume of CAD-RADS 1 and 5 scores during the post-COVID-19 peak compared to baseline (Table 1). Overall, there was no significant difference in proportion of each individual CAD-RADS score between the baseline and post-COVID-19 peak periods (Table 2 ). Furthermore, there was no significant difference in the proportion of patients in the “Significant Stenoses Group” in the post-COVID-19 2020 and 2021 recovery periods compared to baseline.FIG 2 Figure 2 is a graphical representation of the number of coronary CTA exams with CAD-RADS 4A and 4B scores over time. The gray shaded box denotes the peak-COVID-19 period where the radiology department implemented measures in accordance with hospital policies and governmental guidelines to reduce imaging volume. (Color version of figure is available online.) FIG 2 Table 2 Proportions of individual CAD-RADS scores and Cardiac CT Calcium scores between the baseline, peak COVID, 2020 recovery, and 2021 recovery periods. P values reflect comparison to baseline pre-COVID values Table 2 Pre-COVID baseline Peak-COVID P-value Post-COVID 2020 recovery P-value Post-COVID 2021 recovery P-value Coronary CTA CAD-RADS 0 30.9% 31.1% 0.954 29.4% 0.495 27.6% 0.105 CAD-RADS 1 21.7% 23.4% 0.650 17.0% 0.012 18.3% 0.056 CAD-RADS 2 24.3% 24.0% 0.925 28.4% 0.058 28.5% 0.038 CAD-RADS 3 5.9% 6.0% 0.967 8.6% 0.036 9.9% 0.002 CAD-RADS 4A 9.9% 9.0% 0.725 10.6% 0.638 9.9% 0.985 CAD-RADS 4B 2.6% 1.8% 0.550 3.0% 0.631 2.6% 0.997 CAD-RADS 5 4.7% 4.8% 0.956 3.0% 0.052 3.1% 0.056 Significant Stenosis 23.1% 21.6% 0.677 25.2% 0.308 25.5% 0.210 Cardiac CT No CAD (0) 31.9% 23.3% 0.334 38.3% 0.074 38.2% 0.055 Minimal (1-10) 8.2% 10.0% 0.728 11.2% 0.179 12.2% 0.060 Mild (11-100) 22.7% 20.0% 0.737 22.1% 0.851 22.3% 0.898 Moderate (101-400) 25.5% 36.7% 0.189 16.2% 0.001 15.3% <0.001 Severe (>400) 11.7% 10.0% 0.781 12.3% 0.802 12.0% 0.899 There were statistically significant decreases in calcium scores demonstrating no evidence of CAD (9 ± 3 vs 6 ± 4, P = < 0.001), mild CAD (6 ± 3 vs 3 ± 2, P = 0.001), moderate CAD (7 ± 3 vs 2 ± 2, P < 0.001), and severe CAD (3 ± 2 vs 2 ± 2, P = 0.023) during the post-COVID 2020 recovery period compared to baseline. During the post-COVID 2021 recovery period, there continued to be statistically significant decreases in calcium scores demonstrating mild CAD (6 ± 3 vs 4 ± 2, P = 0.01), moderate CAD (7 ± 3 vs 3 ± 2, P < 0.001) and severe CAD (3 ± 3 vs 2 ± 2, P = 0.01) compared to baseline (Table 1). Discussion This study demonstrates a significant decrease in both coronary CTA and coronary calcium score CT exam volume during the peak COVID-19 period with a subsequent differential recovery over the following 2 years. Notably, there has been a muted recovery of coronary calcium score CT volume compared to coronary CTA volume, with a sustained overall decrease in coronary calcium score CT exam volume compared to baseline even after a year following the peak COVID period. While this may be expected due to the elective nature of coronary calcium CT exams, it has yet to be quantified in the literature. Coronary CTA exam volume gradually returned to baseline volume in 2020 following the COVID-19 peak period and even exceeded pre-pandemic baseline volumes in 2021. During the peak COVID-19 period, which spanned approximately 8 weeks, there was a significant decrease in coronary CTA volume for all CAD-RADS scores. These results suggest that diminished access to healthcare during the peak-COVID-19 period likely prevented patients with acute chest pain from seeking appropriate emergency medical care, a finding which is supported by national surveillance data demonstrating a 23% decrease in patient presentations to the emergency department for myocardial infarction between January and May 2020.4 Delays in care for acute emergencies such as acute myocardial infarction have been identified as an important potential contributor to excess mortality during the COVID-19 pandemic.23 , 24 A concerning finding is the muted recovery of coronary calcium score CT volume during the post-COVID-19 peak period, which represents a reflection of delays in return of elective care. As institutions reduced elective imaging, including coronary calcium score CT, to preserve resources during the pandemic, it is becoming apparent that these temporary policies may have prolonged effects during post-COVID-19 recovery periods. Patients may also have postponed elective screening examinations due to the pandemic, as suggested by previous work documenting a sharp drop in internet search engine queries at the first peak of the pandemic for lung, breast, colon, and endometrial cancer screening terms.25 Average coronary calcium CT exam volumes remained well-below baseline levels even 18 months after the COVID-19 peak period. Coronary calcium score CT exams are an important preventative risk-stratification tool for coronary artery disease in low to intermediate risk patients. While not required for initiation of medical therapy, the reduction in calcium score screening exams could conceivably negatively delay the initiation of optimal medical therapy in appropriate patients.26, 27, 28, 29 Overall, the proportion of different CAD-RADS and coronary calcium scores were not significantly different between the peak and post-COVID-19 time periods and baseline. This finding is not surprising for calcium score CT exams given that it is a screening study. Therefore, the decrease in calcium score screening exam volume has likely delayed initiation of appropriate preventive care in patients that qualify. However, the long-term consequences of delaying optimal medical therapy remains unclear. The lack of change in proportion of CAD-RADS scores indicating severe disease during the peak COVID-19 periods despite significant overall decrease in coronary CTA volume provides evidence that some patients with acute coronary syndrome may not have been adequately diagnosed and treated during the COVID-19 pandemic. This finding supports additional studies in the literature that have suggested that delayed care for acute emergencies such as acute myocardial infarction have contributed to excess mortality during the COVID-19 pandemic.23 , 24 Limitations in this study include lack of patient follow-up, which limits assessment for potential increases in morbidity and mortality related to decreases in cardiovascular imaging during the COVID-19 pandemic. Additional studies would be beneficial to directly assess the consequences of delayed coronary CTA and calcium score CT during the peak COVID-19 period. In addition, it has been demonstrated that the COVID-19 pandemic has disproportionately impacted socioeconomically disadvantaged communities. Further investigation is necessary to determine if the decreases in coronary CTA and coronary calcium score CT exam volume observed in this study were even more pronounced in high-risk and vulnerable patient populations during the pandemic.30 In addition, our study did not assess patient factors that might have affected examination volume, such as reluctance to visit medical facilities during the pandemic. Finally, analysis for changes in specific CAD-RADS scores over time was limited by the small patient population and a high degree of week-to-week variability. More robust data from multiple institutions would help clarify the effect of the COVID-19 pandemic on specific CAD-RADS score volumes. We present the first report in the literature analyzing differential decrease and recovery of cardiac CTA and calcium scoring CT exam volume related to the COVID-19 pandemic. The results of this study demonstrate that both coronary CTA and coronary calcium score CT volume decreased drastically during the peak COVID-19 period with gradual recovery to baseline levels for coronary CTA exams. However, there was persistent muted recovery for calcium score CT even 18 months following the COVID-peak period. The sharp decrease in coronary CTA volume during the COVID-peak period, even in patients with severe coronary artery disease, was likely related to decreased access to healthcare during the initial peak in COVID-19 cases. From a population health perspective, the persistently muted recovery of coronary calcium score CT exam volume highlights a concerning trend and suggests the need for improvement in delivery of this important preventative care measure during the COVID-19 pandemic. Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Conflict of interest: The authors declare no relevant conflicts of interest. MDS: Unrelated patent royalties from Frequency Therapeutics and compensation form 2 Minute Medicine, Inc. BG: Unrelated grants to institution – Siemens Healthineers. BPL: Unrelated royalties for textbook associate editor, Elsevier, Inc. ==== Refs References 1 Wright A Salazar A Mirica M The invisible epidemic: Neglected chronic disease management during COVID-19 J Gen Intern Med 35 2020 2816 2817 10.1007/s11606-020-06025-4 32666485 2 Song H Bergman A Chen AT Disruptions in preventive care: Mammograms during the COVID-19 pandemic Health Serv Res 2020 10.1111/1475-6773.13596 3 Lang M Yeung T Mendoza DP Imaging volume trends and recovery during the COVID-19 pandemic: A comparative analysis between a large urban academic hospital and its affiliated imaging centers Acad Radiol 27 2020 1353 1362 10.1016/j.acra.2020.08.008 32830030 4 Lange SJ Ritchey MD Goodman AB Potential indirect effects of the COVID-19 pandemic on use of emergency departments for acute life-threatening conditions — United States, January–May 2020 MMWR Morb Mortal Wkly Rep 69 2020 795 800 10.15585/mmwr.mm6925e2 32584802 5 Lang M Yeung T Shepard JO Operational challenges of a low-dose CT lung cancer screening program during the coronavirus disease 2019 pandemic Chest 2020 10.1016/j.chest.2020.10.045 6 Einstein AJ Shaw LJ Hirschfeld C International impact of COVID-19 on the diagnosis of heart disease J Am Coll Cardiol 77 2021 173 185 10.1016/j.jacc.2020.10.054 33446311 7 Choi AD Abbara S Branch KR Society of cardiovascular computed tomography guidance for use of cardiac computed tomography amidst the COVID-19 pandemic Endorsed by the American College of Cardiology J Cardiovasc Comput Tomogr 14 2020 101 104 10.1016/j.jcct.2020.03.002 32317235 8 Greenland P Blaha MJ Budoff MJ Coronary calcium score and cardiovascular risk J Am Coll Cardiol 72 2018 434 447 10.1016/j.jacc.2018.05.027 30025580 9 Goff DC Lloyd-Jones DM Bennett G 2013 ACC/AHA guideline on the assessment of cardiovascular risk: A report of the American college of cardiology/American heart association task force on practice guidelines Circulation 129 25 SUPPL. 1 2014 49 73 10.1161/01.cir.0000437741.48606.98 10 Budoff MJ Mayrhofer T Ferencik M Prognostic value of coronary artery calcium in the PROMISE study (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) Circulation 136 2017 1993 2005 10.1161/CIRCULATIONAHA.117.030578 28847895 11 Budoff MJ Achenbach S Blumenthal RS Assessment of coronary artery disease by cardiac computed tomography: A scientific statement from the American Heart Association Committee on Cardiovascular Imaging and Intervention, Council on Cardiovascular Radiology and Intervention, and Committee on Cardiac Imaging, Council on Clinical Cardiology Circulation 114 2006 1761 1791 10.1161/CIRCULATIONAHA.106.178458 17015792 12 Meyer MA Baer JM Knolhoff BL Breast and pancreatic cancer interrupt IRF8-dependent dendritic cell development to overcome immune surveillance Nat Commun 9 2018 1250 10.1038/s41467-018-03600-6 29593283 13 Douglas PS Hoffmann U Patel MR Outcomes of anatomical versus functional testing for coronary artery disease N Engl J Med 372 2015 1291 1300 10.1056/nejmoa1415516 25773919 14 Truong QA Schulman-Marcus J Zakroysky P Coronary CT angiography versus standard emergency department evaluation for acute chest pain and diabetic patients: Is there benefit with early coronary CT angiography? Results of the randomized comparative effectiveness ROMICAT II trial J Am Heart Assoc 5 2015 10.1161/JAHA.115.003137 15 Galperin-Aizenberg M Cook TS Hollander JE Cardiac CT angiography in the emergency department Am J Roentgenol 204 3 2015 463 474 10.2214/AJR.14.12657 25714275 16 Hulten E Pickett C Bittencourt MS Outcomes after coronary computed tomography angiography in the emergency department: A systematic review and meta-analysis of randomized, controlled trials J Am Coll Cardiol 61 2013 880 892 10.1016/j.jacc.2012.11.061 23395069 17 Puchner SB Liu T Mayrhofer T High-risk plaque detected on coronary CT angiography predicts acute coronary syndromes independent of significant stenosis in acute chest pain: Results from the ROMICAT-II trial J Am Coll Cardiol 2014 10.1016/j.jacc.2014.05.039 18 Center for Health Information and Analysis. Massachusetts General Hospital: 2020 Hospital Profile 2022 Boston, MA. Available at: https://www.chiamass.gov/assets/docs/r/hospital-profiles/2020/mass-gen.pdf Accessed: October 9, 2022 19 Declaration of a State of Emergency to Respond to COVID-19: Massachusetts. Available at: https://www.mass.gov/news/declaration-of-a-state-of-emergency-to-respond-to-covid-19. Published 2020. Accessed: October 9, 2022. 20 Cury RC Abbara S Achenbach S CAD-RADSTM Coronary Artery Disease – Reporting and Data System. An expert consensus document of the Society of Cardiovascular Computed Tomography (SCCT), the American College of Radiology (ACR) and the North American Society for Cardiovascular Imaging (NASCI). Endorsed by the American College of Cardiology J Cardiovasc Comput Tomogr 10 2016 269 281 10.1016/j.jcct.2016.04.005 27318587 21 Agatston AS Janowitz WR Hildner FJ Quantification of coronary artery calcium using ultrafast computed tomography J Am Coll Cardiol 15 1990 827 832 10.1016/0735-1097(90)90282-T 2407762 22 R: A language and environment for statistical computing. 2017. Available at: https://www.r-project.org/. Accessed: October 9, 2022. 23 Woolf SH Chapman DA Sabo RT Excess deaths from COVID-19 and other causes, March-April 2020 JAMA 2020 10.1001/jama.2020.11787 24 Woolf SH Chapman DA Sabo RT Excess deaths from COVID-19 and Other Causes, March-July 2020 JAMA - J Am Med Assoc 324 2020 1562 1564 10.1001/jama.2020.19545 25 Snyder A Jang S Nazari IS Google search volume trends for cancer screening terms during the COVID-19 pandemic J Med Screen 2021 10.1177/0969141321999426 26 Budoff MJ Shaw LJ Liu ST Long-term prognosis associated with coronary calcification. Observations from a registry of 25,253 patients J Am Coll Cardiol 49 2007 1860 1870 10.1016/j.jacc.2006.10.079 17481445 27 Raggi P Gongora MC Gopal A Coronary artery calcium to predict all-cause mortality in elderly men and women J Am Coll Cardiol 52 2008 17 23 10.1016/j.jacc.2008.04.004 18582630 28 Polonsky TS McClelland RL Jorgensen NW Coronary artery calcium score and risk classification for coronary heart disease prediction JAMA - J Am Med Assoc 303 2010 1610 1616 10.1001/jama.2010.461 29 Burge MR Eaton RP Comerci G Management of asymptomatic patients with positive coronary artery calcium scans J Endocr Soc 1 2017 588 599 10.1210/js.2016-1080 29264512 30 Thakur N Lovinsky-Desir S Bime C The structural and social determinants of the racial/ethnic disparities in the U.S. COVID-19 pandemic what's our role? Am J Respir Crit Care Med 202 2020 943 949 10.1164/rccm.202005-1523PP 32677842
PMC009xxxxxx/PMC9676901.txt	==== Front J Behav Med J Behav Med Journal of Behavioral Medicine 0160-7715 1573-3521 Springer US New York 36400880 373 10.1007/s10865-022-00373-8 Article The role of childhood unpredictability in adult health http://orcid.org/0000-0002-6534-3341 Maner Jon K. [email protected] 1 Hasty Connor R. 1 Martinez Jose L. 1 Ehrlich Katherine B. 2 Gerend Mary A. 3 1 grid.255986.5 0000 0004 0472 0419 Department of Psychology, Florida State University, 1107 W. Call St., Tallahassee, FL 32304 USA 2 grid.213876.9 0000 0004 1936 738X Department of Psychology, University of Georgia, Athens, USA 3 grid.255986.5 0000 0004 0472 0419 Department of Behavioral Sciences and Social Medicine, Florida State University, Tallahassee, USA 18 11 2022 2023 46 3 417428 22 4 2022 18 10 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. This research differentiated childhood unpredictability (i.e., perceptions of uncertainty or instability due to turbulent environmental changes) from other related constructs to identify its role in adult health. Study 1 (N = 441) showed that, beyond other childhood adversity variables (poverty and adverse childhood experiences or ACEs) and demographic characteristics, perceptions of unpredictability were associated with greater functional disability and worse health-related quality of life (assessed via the CDC’s HRQOL Healthy Days measure and the RAND SF-36). Study 2 (N = 564) replicated those findings in a more racially diverse sample and showed that associations with childhood unpredictability held while also controlling for the Big 5 personality traits. Findings suggest that effects of unpredictability were especially pronounced among Hispanic (in Study 1), and Black/African American and low-income participants (in Study 2). Experiencing childhood environments that are perceived to be uncertain, unstable, or uncontrollable may put children on a path toward poor health outcomes in adulthood. Findings advance theories of child adversity and health and identify childhood unpredictability as a potentially valuable target for intervention. Supplementary Information The online version contains supplementary material available at 10.1007/s10865-022-00373-8. Keywords Development Child adversity Life history theory Chronic disease Evolution issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction A range of health problems in adulthood have been linked with exposure to adverse experiences in childhood (Adler et al., 1993; Bradley & Corwyn, 2002; Chen et al., 2002; Ehrlich et al., 2016). Adults who experienced low-income, abusive, or traumatic childhoods are at substantially higher risk for experiencing chronic disease, physical and emotional disability, and low health-related quality of life (Boyce & Ellis, 2005; Chen & Miller, 2013; Miller et al., 2011). Despite the consistency of such findings, the field lacks a clear understanding of what psychological processes are responsible for translating adverse childhood experiences into negative adult health outcomes. Although many studies document the contribution of early life stress to adult health outcomes (e.g., Dube et al., 2001, 2003; Felliti et al., 1998), such research at times leaves uninvestigated the specific cognitive mechanisms that may explain effects of child adversity on adult health. Identifying those mechanisms provides key information about the psychological, behavioral, and neuroendocrine pathways through which childhood experiences affect adult health and offers insight into potentially valuable targets for intervention. The current study is the first to assess perceptions of childhood unpredictability—the extent to which childhood experiences are characterized by perceptions of uncertainty or instability due to turbulent changes in the environment—to evaluate their role in adult functional health status and health-related quality of life. The role of perceived unpredictability Theories of adaptive calibration (e.g., Del Giudice et al., 2011) such as life history theory (Belsky et al., 2012; Brumbach et al., 2009; Cabeza de Baca et al., 2016; Ellis et al., 2009; McDade, 2003) suggest that, early in childhood, psychological, behavioral, and neuroendocrine processes are calibrated to the perceived level of unpredictability in one’s environment (Del Giudice, 2009; Ellis & Del Giudice, 2019). Childhood unpredictability is characterized by the presence of uncertainty or instability due to turbulent changes in the environment. The core element of unpredictability involves the perception of social and physical threats that are inconsistent across time and situations and are, therefore, unpredictable. For example, perceptions of unpredictability can stem from inconsistency across time in the degree of support a child receives from their primary caregiver, uncertainty in a child’s ongoing interactions with teachers and peers, or variability in a child’s daily schedule or routines. Perceived unpredictability may serve as a mechanism through which adverse childhood experiences (ACEs) affect health into adulthood. Many adverse childhood experiences, such as those involving trauma, abuse, and neglect (e.g., Dube et al., 2001; Felitti et al., 1998), as well as inconsistent caregiving and access to social support (e.g., Baram et al., 2012; Gee & Cohodes, 2021) are likely to contribute to perceptions of unpredictability. Such experiences can destabilize the social (or physical) environment and generate perceived threats that vary uncontrollably across time and situations. Some parental divorces, for example, can create home environments that are chaotic, hostile, or unsupportive (Kelly & Emery, 2003), and thus can contribute to feelings of unpredictability (Doom et al., 2016; Martinez et al., 2022). Yet, the broader construct of unpredictability is not effectively captured by existing measures of ACEs, which focus narrowly on whether people were ever exposed to particular experiences during childhood, rather than on the degree to which they were exposed to those experiences or the extent to which those experiences were perceived to vary unpredictably across time and situations. For example, the quality of home environments for children whose parents divorce can range from routinized and predictable to chaotic and unsupportive (Kelly & Emery, 2003). Thus, simply assessing whether one’s parents divorced fails to capture the quality of the home experience or how predictable versus unpredictable it was perceived to be. Perceptions of childhood unpredictability are also distinct from the experience of poverty. Poverty entails resource scarcity and often includes exposure to financial hardship, inadequate nutrition, poor physical living conditions, and lack of access to health care services (Chen & Miller, 2013). Effects of poverty are well-represented in models of allostatic load, toxic stress, and chronic deprivation, all of which encompass a focus on lack of access to resources (McEwen & Stellar, 1993; McLaughlin & Sheridan, 2016). However, whereas poverty often entails financial hardship experienced in a relatively consistent manner across time and situations, unpredictability entails the perception of social and physical threats that are highly variable and that often come from sources other than financial hardship (e.g., unstable relationships with caregivers). Thus, while poverty and unpredictability are correlated, they are conceptually and operationally distinct (see Maranges et al., 2022; Martinez et al., 2022). Perceptions of childhood unpredictability and adult health The current research is the first to pinpoint perceptions of childhood unpredictability as a potentially important contributor to adult health outcomes. This research addressed three overarching hypotheses. First, two studies tested the hypothesis that perceptions of unpredictability would be robustly associated with adult functional ability and health-related quality of life over and above poverty and ACEs, while controlling for demographic covariates (age, gender, racial and ethnic minority status, and current household income) and personality traits. Second, the studies used mediational analyses to test the hypothesis that perceptions of unpredictability might mediate associations between ACEs and adult health outcomes, i.e., that ACEs damage health in part because those experiences generate feelings of unpredictability. Third, the studies assessed whether effects of unpredictability are larger among populations who, by virtue of their race, ethnicity, or social class, may be characterized by high levels of stress due to prejudice, discrimination, or lack of financial resources. We reasoned that such populations may be especially vulnerable to experiencing cumulative effects of unpredictable environments. We thus assessed possible moderating effects of race, ethnicity, and current income. This article reports findings from two studies. Study 1 provided preliminary tests of the three research questions above by including a relatively wide range of measures reflecting functional health status and health-related quality of life. Study 2 targeted a smaller number of outcome measures, included additional measures of personality traits to serve as covariates, and recruited a larger and more diverse sample. Thus, while Study 1 provided initial tests of the associations between childhood unpredictability and health outcomes, Study 2 replicated and extended Study 1 by allowing for a stronger assessment of whether those relationships depend on demographic group and whether they hold over and above basic aspects of personality. Study 1 Method Participants An online community sample of 520 U.S. participants was recruited via CloudResearch. All adult participants were eligible to participate. Based on a priori criteria, 79 participants who failed one or more of three attention checks embedded in self-report items (e.g., “For this question please select strongly disagree”) were excluded from analyses. The final sample included 441 participants. Participants were compensated $0.50. See Table 1 for sample demographic characteristics. Data were collected in April–May, 2020. The study was approved by the Florida State University Institutional Review Board (IRB) and informed consent was obtained from all participants prior to participation. Data and data analytic syntax for both studies can be accessed here: https://osf.io/m69sq/?view_only=6a63862623d74ad2a23572e3d8fbdde7Table 1 Sample demographic characteristics Study 1 Study 2 Variable N (%) or M (SD) N (%) or M (SD) Age (years) M = 32.07, SD = 11.20 Range = 18–70 M = 38.00, SD = 12.47Range = 18–76 Gender 208 men, 232 women, 1 other 201 men, 356 women, 3 nonbinary, 4 other Race American Indian 8 (2%) 4 (1%) Asian 51 (12%) 31 (5%) Native Hawaiian/Pacific Islander 2 (< 1%) 1 (< 1%) Black or African American 36 (8%) 201 (36%) White 311 (71%) 303 (54%) Multi-racial 16 (4%) 14 (2%) Unknown/Did not report 8 (2%) 8 (1%) Other 9 (2%) 2 (< 1%) Hispanic or Latino Yes 90 (20%) 46 (8%) No 332 (75%) 507 (90%) Unknown/Did not report 19 (4%) 11 (2%) Current annual household Income $10,000 or less 22 (5%) 30 (5%) $10,001–$19,999 28 (6%) 34 (6%) $20,000–$29,999 58 (13%) 47 (8%) $30,000–$39,999 52 (12%) 75 (13%) $40,000–$49,999 32 (7%) 56 (10%) $50,000–$59,999 42 (10%) 64 (11%) $60,000–$69,999 24 (5%) 45 (8%) $70,000–$79,999 43 (10%) 50 (9%) $80,000–$89,999 23 (5%) 31 (5%) $90,001–$99,999 25 (6%) 21 (4%) $100,000–$150,000 53 (12%) 75 (13%) $150,001 or more 39 (9%) 36 (6%) Percentages may not total 100% due to rounding error Measures Perceptions of Childhood Unpredictability. Fifteen items validated in previous work (Maranges et al., 2022) assessed perceived unpredictability during the first 10 years of childhood (e.g., “I never knew when my parents would be there to pick me up from school”, “I often did not know what to expect from other kids at school”, “When I left my house I was never quite certain what would happen in my neighborhood”) (1 = strongly disagree, 7 = strongly agree) (M = 3.13, SD = 1.53, range = 1.00 to 6.93, α = 0.95). The scale has been shown to demonstrate strong convergent, discriminant, and predictive validity (Maranges et al., 2022). Perceptions of Childhood Poverty. Eleven items from previous work (Maranges et al., 2021, 2022) assessed perceptions of childhood poverty and financial hardship (e.g., “My family rarely had enough money to go out for a nice dinner”, “My family was strained financially”, “I felt relatively wealthy compared with other kids in my school”; reverse-scored). (1 = strongly disagree, 7 = strongly agree) (M = 3.83, SD = 1.42, range = 1.00 to 7.00, α = 0.91). Adverse Child Experiences (ACEs; Dube et al., 2001). The ACEs scale was originally generated for the CDC-Kaiser Permanente Adverse Childhood Experiences study, a comprehensive study of childhood abuse and neglect (Felitti et al., 1998). The current study used the ACEs scale later adapted by Dube et al. (2001) to include a 10-item checklist assessing three forms of abuse (emotional, physical, sexual), two forms of neglect (emotional, physical), and five forms of household dysfunction including exposure to domestic violence, substance use, divorce, mental illness, and criminal activity (all experienced through age 18). Responses were summed to produce a total ACEs score (M = 2.89, SD = 2.67, scores ranged from 0 to 10). CDC’s Health-Related Quality of Life (HRQOL; CDC, 1993). The HRQOL has been used extensively to assess health-related quality of life and is included in the Behavioral Risk Factor Surveillance System, the National Health and Nutrition Examination Survey, and the Medicare Health Outcomes Survey. The HRQOL consists of two separate modules. The core module prompts participants to report the number of days (out of the past 30) in which they experienced poor physical health and mental health. Based on CDC guidelines, those two items were averaged to provide a core measure of unhealthy days (M = 14.40, SD = 10.83, α = 0.70). The symptoms module includes five items to assess the number of days (out of the past 30 days) in which (1) pain caused participants to limit their activities, (2) they felt sad or depressed, (3) they felt anxious, (4) they did not get enough rest or sleep, and (5) they felt healthy and full of energy. Items were averaged after reverse-scoring the final item (M = 11.26, SD = 6.57, α = 0.78). Higher scores indicate worse health-related quality of life. The CDC HRQOL demonstrates strong psychometric properties in both community and clinical settings (Mielenz et al., 2006). RAND SF-36 (RAND, 1995). The 36-item SF-36 assesses functional ability and includes eight subscales assessing Physical Functioning, Role Limitations due to Physical Health, Role Limitations due to Emotional Health, Energy/Fatigue, Emotional Well-Being, Social Functioning, Pain, and General Health. Subscale scores were calculated according to RAND’s guidelines. Scoring instructions can be found at https://www.rand.org/health-care/surveys_tools/mos/36-item-short-form.html. Higher scores reflect better health-related functional ability. The SF-36 demonstrates strong psychometric properties, as well as predictive validity for both physical and mental health diagnostic outcomes (Elliott et al., 2003; Parshall et al., 2008). Statistical approach Preliminary analyses assessed correlations among all variables. Primary analyses first used multiple regression to assess independent associations between outcome variables (CDC HRQOL core and symptoms modules and SF-36 subscales), experiences of childhood unpredictability and poverty, and ACEs. We included age, gender, race, ethnicity, and current household income as demographic covariates. To differentiate racial/ethnic minority and majority participants, we focused on differences between participants identifying as Black/African American (vs non-Black) or Hispanic/Latino (vs non-Hispanic). Second, mediational analyses (using the Model 4 PROCESS macro in SPSS; Hayes, 2017) assessed whether perceived unpredictability might serve as a psychological mechanism explaining the link between ACEs and adult health outcomes. Third, regression analyses examined whether any effects of unpredictability might be moderated by participant race, ethnicity, or income. Because the SF-36 consists of eight subscales, for analyses of the SF-36 we used a conservative Bonferroni correction to reduce alpha inflation and avoid Type I error. The alpha level used to determine statistical significance was 0.05/8 = 0.00625. Study 2 provided a more targeted focus on two outcome variables (CDC’s HRQOL core module and the SF-36 Physical Functioning subscale). To facilitate comparison across the two studies, presentation of Study 1 results in the main text highlights those two outcome variables. There were no missing data in this study. To simplify statistical models, only participants self-identifying as male or female were included. Sensitivity analysis indicated that the study was well-powered (> 0.80) to detect effect sizes as small as r = 0.13 in both correlational analyses and regression analyses with 8 predictors. Results Correlations among variables are reported in Table 2, which includes all predictors and the two outcomes included in both studies (CDC HRQOL core module and SF-36 Physical Functioning scale). Correlations that include all 10 outcomes are in Supplemental Materials Table S1. Perceived childhood unpredictability, poverty, and ACEs were all moderately to strongly correlated, and all three were significantly correlated with all of the outcome measures.Table 2 Correlations among predictor variables and health-related outcome measures (studies 1 and 2) 1 2 3 4 5 6 7 8 9 10 1. CDC HRQOL – − 0.47* 0.35* 0.19* 0.29* − 0.15* − 0.16* 0.02 − 0.01 − 0.06* 2. Physical Functioning − 0.41* – − 0.32* − 0.18* − 0.23* 0.10* − 0.19* − 0.01 − 0.03 0.16* 3. Unpred ictability 0.46* − 0.58* – 0.49* 0.69* − 0.19* − 0.17* − 0.09* 0.09* − 0.17* 4. Poverty 0.28* − 0.21* 0.54* – 0.44* − 0.19* 0.04 − 0.00 0.05 − 0.06 5. ACEs 0.44* − 0.36* 0.67* 0.41* – − 0.16*** − 0.08 0.08* 0.10* − 0.05 6. Annual Income − 0.11* 0.16 − 0.21* − 0.20* − 0.24* – 0.05 0.03 − 0.19* 0.04 7. Age 0.08 − 0.29* 0.22*** 0.11* 0.23*** 0.11* – 0.07 − 0.11* 0.08 8. Gender 0.02 0.16 − 0.17* − 0.05 − 0.02 − 0.05 − 0.20* – 0.03 0.07 9. Race − 0.05 0.01 − 0.02 − 0.04 − 0.01 − 0.17* − 0.04 0.02 – 0.00 10. Ethnicity 0.07 − 0.18* 0.17* 0.12* 0.12* − 0.08 − 0.02 − 0.01 − 0.05 – Study 1 (N = 440) is below the diagonal; Study 2 (N = 557) is above the diagonal. Gender: 1 = Male, 2 = Female; Race: 0 = non-Black/African American, 1 = Black/African American, Ethnicity: 0 = non-Hispanic, 1 = Hispanic. Correlations with race, ethnicity, and gender reflect Pearson point biserial correlations. *p < 0.001, p < 0.01, *p < 0.05 Regression analyses for all outcomes are reported in Table 3. Once the overlap among predictors was taken into account, we observed significant associations between childhood unpredictability and nine out of ten outcome measures (the one exception was the energy/fatigue SF-36 subscale).Table 3 Study 1 Regression analyses: predictors of functional ability and health-related quality of life Beta t p Partial r CDC HRQOL Core module Unpredictability 0.31 4.92 < 0.001 0.23 Poverty 0.03 0.56 0.58 0.03 ACEs 0.23 3.98 < 0.001 0.19 Age − 0.04 − 0.79 0.43 − 0.04 Gender 0.07 1.62 0.11 0.08 Current income 0.01 0.31 0.76 0.02 Black − 0.04 − 0.99 0.32 − 0.05 Hispanic − 0.02 − 0.44 0.66 − 0.02 Symptoms module Unpredictability 0.23 3.62 < 0.001 0.17 Poverty 0.07 1.37 0.17 0.07 ACEs 0.29 5.11 < 0.001 0.24 Age − 0.02 − 0.48 0.63 − 0.02 Gender 0.13 3.00 0.003 0.14 Current income − 0.01 − 0.21 0.84 − 0.01 Black − 0.07 − 1.69 0.09 − 0.08 Hispanic − 0.03 − 0.81 0.42 − 0.04 RAND SF-36 Physical functioning Unpredictability − 0.63 − 11.14 < 0.001 − 0.47 Poverty 0.15 3.25 0.001 0.16 ACEs 0.09 1.63 0.10 0.08 Age − 0.19 − 4.78 < 0.001 − 0.22 Gender 0.03 0.72 0.47 0.04 Current income 0.09 2.18 0.03 0.11 Black 0.01 0.34 0.74 0.02 Hispanic − 0.10 − 2.58 0.01 − 0.12 Role limitations-physical Unpredictability − 0.47 − 7.46 < 0.001 − 0.34 Poverty 0.05 0.97 0.34 0.05 ACEs − 0.01 − 0.16 0.87 − 0.01 Age − 0.06 − 1.44 0.15 − 0.07 Gender 0.00 0.03 0.98 0.00 Current income 0.10 2.16 0.03 0.10 Black − 0.02 − 0.37 0.71 − 0.02 Hispanic − 0.03 − 0.79 0.43 − 0.04 Role limitations-emotional Unpredictability − 0.25 − 3.87 < 0.001 − 0.18 Poverty 0.02 0.29 0.78 0.01 ACEs − 0.22 − 3.75 < 0.001 − 0.18 Age 0.11 2.45 0.02 0.12 Gender − 0.18 − 3.98 < 0.001 − 0.19 Current income − 0.02 − 0.34 0.74 − 0.02 Black 0.10 2.26 0.03 0.11 Hispanic 0.08 1.89 0.06 0.09 Energy/fatigue Unpredictability − 0.06 − 0.91 0.37 − 0.04 Poverty − 0.10 − 1.84 0.07 − 0.09 ACEs − 0.21 − 3.46 0.001 − 0.16 Age 0.17 3.57 < 0.001 0.17 Gender − 0.20 − 4.38 < 0.001 − 0.21 Current income − 0.01 − 0.14 0.89 − 0.01 Black 0.03 0.61 0.54 0.03 Hispanic 0.16 3.51 < 0.001 0.17 Emotional well-being Unpredictability − 0.20 − 2.96 0.003 − 0.14 Poverty − 0.07 − 1.30 0.20 − 0.06 ACEs − 0.22 − 3.71 < 0.001 − 0.18 Age 0.11 2.27 0.02 0.11 Gender − 0.08 − 1.86 0.06 − 0.09 Current income 0.04 0.80 0.42 0.04 Black 0.06 1.23 0.22 0.06 Hispanic 0.11 2.53 0.01 0.12 Social functioning Unpredictability − 0.40 − 6.33 < 0.001 − 0.29 Poverty − 0.00 − 0.03 0.98 − 0.00 ACEs − 0.13 − 2.19 0.03 − 0.11 Age 0.00 0.02 0.98 0.00 Gender − 0.15 − 3.38 0.001 − 0.16 Current income 0.06 1.30 0.19 0.06 Black 0.02 0.53 0.60 0.03 Hispanic − 0.01 − 0.33 0.74 − 0.02 Pain Unpredictability − 0.51 − 8.33 < 0.001 − 0.37 Poverty 0.07 1.36 0.17 0.07 ACEs − 0.01 − 0.20 0.85 − 0.01 Age − 0.17 − 3.95 < 0.001 − 0.19 Gender − 0.05 − 1.18 0.24 − 0.06 Current income 0.07 1.58 0.11 0.08 Black 0.04 1.04 0.30 0.05 Hispanic 0.01 0.28 0.78 0.01 General health Unpredictability − 0.24 − 3.73 < 0.001 − 0.18 Poverty − 0.10 − 1.99 0.05 − 0.10 ACEs − 0.15 − 2.57 0.01 − 0.12 Age − 0.02 − 0.37 0.71 − 0.02 Gender − 0.17 − 3.76 < 0.001 − 0.18 Current income 0.08 1.64 0.10 0.08 Black 0.00 0.01 10.00 0.00 Hispanic 0.06 1.28 0.20 0.06 N = 440. Gender: 1 = Male, 2 = Female. Race: 0 = non-Black/African American, 1 = Black/African American. Ethnicity: 0 = non-Hispanic, 1 = Hispanic. For the CDC HRQOL measures, higher scores indicate worse health-related quality of life. For the SF-36 measures, higher scores reflect higher health-related functional ability We next tested whether perceived unpredictability statistically mediated the association between ACEs and each outcome measure. The indirect effect was significant for all outcome variables except for the energy/fatigue subscale of the SF-36 (see Supplemental Materials Table S2). Figure 1 depicts the mediation model for the CDC HRQOL core module and the SF-36 Physical Functioning scale. Both standardized indirect effects were significant (HRQOL: Z = 0.20, SE = 0.04, CI [0.11, 0.28]; Physical Functioning: Z = − 0.41, SE = 0.04, CI [− 0.49, − 0.34]).Fig. 1 Study 1 Mediating effects of perceived childhood unpredictability Moderation analyses assessed possible moderating effects of race, ethnicity, and income. To ensure that any moderated effects were independent of one another, we included centered interaction terms between unpredictability and race, ethnicity, and income simultaneously in the regression models. See Supplemental Materials Table S3 for full moderation results. For the CDC HRQOL symptoms module, we observed a significant interaction between childhood unpredictability and ethnicity, B = 0.11, t = 2.51, p = 0.01. Simple slopes analyses showed that unpredictability was more strongly tied to poor HRQOL in Hispanic, B = 0.43, t = 4.25, p < 0.001, relative to non-Hispanic, B = 0.16, t = 2.47, p = 0.01, participants. Although the moderated effect for the HRQOL core module only approached significance, B = 0.07, t = 1.68, p = 0.09, the pattern of simple slopes was similar to that for the symptoms module: Unpredictability was more strongly tied to poor HRQOL in Hispanic, B = 0.45, t = 4.37, p < 0.001, relative to non-Hispanic, B = 0.27, t = 3.98, p < 0.001, participants (see Supplemental Materials Fig. S1). No significant moderating effects were found for the SF-36 subscales; although some were significant at the 0.05 level, none were significant at the more conservative 0.00625 level (see Supplemental Materials Table S3). Discussion Study 1 provides preliminary evidence for robust connections between perceptions of childhood unpredictability and adult health-related quality of life and functional ability. Those connections were observed over and above ACEs, perceptions of resource scarcity, and a range of demographic variables. Indeed, reports of experiencing an unpredictable childhood were at least as consistent a predictor as having faced high levels of poverty or ACEs. Although tests of mediation are limited by the cross-sectional nature of the study, findings are consistent with the hypothesis that perceived unpredictability might explain the association between ACEs and adult HRQOL and functional disability. We saw some evidence for moderating effects of ethnicity, such that perceptions of unpredictability were tied to low HRQOL more strongly for Hispanic than non-Hispanic participants. This pattern provides preliminary evidence that effects of unpredictability may be pronounced among members of underrepresented groups at relatively high risk for experiencing stress associated with discrimination. No moderating effects of race were found. However, the lack of such moderating effects could be due to a lack of racial diversity within the sample, a problem we remedy in the second study. Study 2 Study 2 provided an opportunity to replicate associations between perceptions of childhood unpredictability and adult functional ability and health-related quality of life. Three features of Study 2 enhanced the investigation. First, Study 2 recruited a larger and more racially diverse sample to increase statistical power to detect potential moderating effects. Second, Study 2 included a more targeted focus on two outcome variables: the CDC’s core HRQOL module and the SF-36 Physical Functioning measure. We chose the Physical Functioning measure because it is the most comprehensive (10 items) and reliable of the SF-36 subscales (RAND, 1995) and is the most differentiable from the CDC HRQOL core module (Barile et al., 2016). Third, reports of mental and physical health, as well as retrospective reports of childhood adversity, may be influenced by personality traits such as neuroticism (Baldwin et al., 2019). Therefore, to ensure that findings do not simply reflect shared associations with personality traits, we measured and controlled for the Big 5 personality traits (John & Srivastava, 1999). Method Participants A sample of 564 community participants living in the U.S. was recruited via CloudResearch. Recruitment was open to all adult participants with the constraint that we aimed to recruit a minimum of 200 Black/African American participants. Similar to Study 1, participants who failed one or more of three attention checks embedded in self-report items were not permitted to complete the study and were excluded. Participants were compensated $2. See Table 1 for sample demographic characteristics. Data were collected in March–May, 2021. The study was approved by the Florida State University IRB and informed consent was obtained from all participants prior to participation. Measures Study 2 used the same measures of childhood unpredictability, poverty, and ACEs from Study 1. Study 2 included two of the outcome measures from Study 1: the CDC HRQOL core module and the 10-item SF-36 Physical Functioning scale. To measure the Big 5 personality traits, we used the Ten-Item Personality Inventory (Gosling et al., 2003). The scale provided measures of Emotional Stability/Neuroticism, Conscientiousness, Agreeableness, Openness, and Extraversion. Statistical approach Preliminary analyses assessed correlations among variables. Primary analyses relied on hierarchical regression to assess independent associations between outcome measures (CDC HRQOL core module, SF-36 Physical Functioning) and measures of childhood adversity (unpredictability, poverty, and ACEs). The first step of the regression model replicated analyses from Study 1: outcomes were predicted from measures of childhood adversity and demographic covariates including participant age, gender, race (Black/African American vs. non-Black), ethnicity (Hispanic/Latino vs. non-Hispanic), and current income. In the second step of the regression model, we included the Big 5 personality traits as additional covariates. Moderation analyses built on this regression model to examine whether effects of unpredictability were moderated by race, ethnicity, or current income; all three centered interaction terms were included simultaneously to ensure that any moderated effects were independent of one another. Mediational analyses assessed whether perceived unpredictability might mediate effects of ACEs. There were no missing data. To simplify statistical models, only participants self-identifying as male or female were included. Sensitivity analysis indicated that the study was well-powered (> 0.80) to detect effect sizes as small as r = 0.12 in both correlational analyses and regression analyses with 13 predictors. Results Correlations are in Table 2. As in Study 1, all three measures of childhood adversity were correlated with one another, and all three were significantly correlated with the two outcome measures. Primary regression analyses accounted for the correlations among predictors and replicated findings from Study 1 (See Table 4). Childhood unpredictability was significantly associated with both outcome measures, while controlling for poverty, ACEs, and demographic covariates (step 1), as well as all Big 5 personality traits (step 2).Table 4 Study 2 regression analyses: predictors of functional disability and health-related quality of life Dependent variable Predictor Beta t p Partial r CDC HRQOL Step 1 Unpredictability 0.25 4.09 < 0.001 0.17 Poverty 0.02 0.42 0.68 0.02 ACEs 0.10 1.70 0.09 0.07 Age − 0.12 − 3.03 0.003 − 0.13 Gender 0.05 1.21 0.23 0.05 Current income − 0.09 − 2.20 0.03 − 0.09 Black − 0.07 − 1.79 0.07 − 0.08 Hispanic − 0.00 − 0.09 0.93 − 0.00 Step 2 Unpredictability 0.13 2.36 0.02 0.10 Poverty 0.01 0.20 0.84 0.01 ACEs 0.07 1.30 0.19 0.06 Age − 0.01 − 0.14 0.89 − 0.01 Gender − 0.02 − 0.39 0.70 − 0.02 Current income − 0.01 − 0.19 0.85 − 0.01 Black 0.04 1.02 0.31 0.04 Hispanic 0.00 − .05 0.96 − 0.00 Extraversion − 0.08 − 2.12 0.03 − 0.09 Agreeableness − 0.02 − 0.40 0.69 − 0.02 Conscientiousness − 0.12 − 2.74 0.01 − 0.12 Emotional stability − 0.40 − 9.02 < 001 − 0.36 Openness − 0.01 − 0.30 0.77 − 0.01 Physical functioning Step 1 Unpredictability − 0.34 − 5.68 < 0.001 − 0.24 Poverty 0.01 0.25 0.80 0.01 ACEs − 0.00 − 0.03 0.97 − 0.00 Age − 0.26 − 6.44 < 0.001 − 0.27 Gender − 0.03 − 0.71 0.48 − 0.03 Current income 0.04 1.09 0.28 0.05 Black − 0.02 − 0.51 0.61 − 0.02 Hispanic 0.12 3.06 0.002 0.13 Step 2 Unpredictability − 0.28 − 4.72 < 0.001 − 0.20 Poverty 0.01 0.31 0.75 0.01 ACEs 0.01 0.21 0.84 0.01 Age − 0.31 − 7.45 < 0.001 − 0.31 Gender − 0.01 − 0.15 0.88 − 0.01 Current income 0.01 0.26 0.80 0.01 Black − 0.07 − 1.66 0.10 − 0.07 Hispanic 0.12 2.97 0.003 0.13 Extraversion 0.02 0.58 0.56 0.03 Agreeableness 0.02 0.46 0.64 0.02 Conscientiousness 0.06 1.22 0.22 0.05 Emotional stability 0.16 3.30 0.001 0.14 Openness 0.00 0.09 0.93 0.00 N = 557. Gender: 1 = Male, 2 = Female. Race: 0 = non-Black/African American, 1 = Black/African American. Ethnicity: 0 = non-Hispanic, 1 = Hispanic. For the CDC HRQOL measure, higher scores indicate worse health-related quality of life. For Physical Functioning, higher scores reflect better functional ability We tested whether perceived unpredictability mediated the association between ACEs and the two outcomes. Replicating Study 1, both standardized indirect effects were significant (Unhealthy Days: Z = 0.19, SE = 0.04, CI [0.11, 0.27]; Physical Functioning: Z = − 0.21, SE = 0.04, CI [− 0.30, − 0.13). See Fig. 2.Fig. 2 Study 2 mediating effects of perceived childhood unpredictability Moderation analyses examined potential moderating effects of race, ethnicity, and income. We observed a significant (B = − 0.12, t = − 2.97, p = 0.003) moderating effect of race on Physical Functioning. Simple slopes analyses showed that there was a larger effect of unpredictability in Black (B = − 0.49, t = − 6.62, p < 0.001), compared with non-Black (B = − 0.32, t = − 5.38, p < 0.001) participants (see Supplemental Materials Fig. S2). The moderating effect of race on HRQOL was not significant (B = 0.06, t = 1.35, p = 0.18), but the pattern of simple effects was similar: a larger effect of unpredictability was seen in Black (B = 0.32, t = 4.24, p < 0.001), compared with non-Black (B = 0.24, t = 3.92, p < 0.001) participants (see Fig S2). No moderating effects of ethnicity were found on either measure (HRQOL: B = − 0.00, t = − 0.01, p = 1.00; Physical Functioning: B = 0.06, t = 1.47, p = 0.14). We also saw significant moderating effects of current income on both outcome measures (HRQOL: B = − 0.08, t = − 2.03, p = 0.04; Physical Functioning: B = 0.08, t = 2.04, p = 0.04). See Fig. S3. Simple slopes analyses showed that effects of unpredictability were considerably larger among those with lower incomes (1SD below the mean income: HRQOL: B = 0.33, t = 4.66, p < 0.001; Physical Functioning: B = − 0.42, t = − 6.14, p < 0.001), compared with higher incomes (1SD above the mean: HRQOL: B = 0.14, t = 1.75, p = 0.08; Physical Functioning: B = − 0.22, t = − 2.84, p = 0.005). Discussion Study 2 replicated evidence for robust associations between perceived childhood unpredictability and adult functional disability and health-related quality of life. Those associations were observed over and above other measures of childhood adversity, demographics, and Big 5 personality traits. As in Study 1, we saw evidence that effects of ACEs were statistically mediated by perceived unpredictability. We also observed evidence for independent moderating effects of race and income. Effects were relatively larger among Black (compared with non-Black) and lower income (compared with higher income) participants. No moderating effects of ethnicity were found, although this could be due to the relatively small number of Hispanic participants in this sample. General discussion Findings from two studies identify perceptions of childhood unpredictability as a key psychological factor potentially contributing to functional disability and low health-related quality of life in adulthood. The associations between perceived childhood unpredictability and health-related outcomes were observed while controlling for other measures of childhood adversity (poverty and ACEs), demographic variables (age, gender, racial/ethnic minority status, current household income), and personality (Big 5 traits). Although we replicated zero-order correlations between adult health-related outcomes and ACEs (and poverty), unpredictability emerged in regression analyses as an especially robust and independent predictor. That pattern, coupled with mediational analyses, is consistent with the possibility that perceptions of unpredictability partially explain associations between ACEs and poor adult health. (It is important to note, however, that tests of mediation are limited by the cross-sectional design of these studies and thus strong causal interpretations are not warranted.) Childhood experiences such as physical or emotional abuse or inconsistent caregiving can create a sense of instability and lack of control and certainty, as well as a psychological focus on short term (rather than long-term) rewards and goals. Over time, such processes may culminate in greater risk for poor health in adulthood. This work thus advances the literature by identifying perceptions of unpredictability as a potentially important factor underlying functional disability and poor health-related quality of life in adulthood. The effects of childhood unpredictability on adult health may reflect psychological, behavioral, and neuroendocrine pathways. Psychological pathways reflect the fact that unpredictability entails a lack of stability, certainty, and control (Mittal & Griskevicius, 2014), and thus requires high levels of cognitive vigilance (Frankenhuis et al., 2016; Pepper & Nettle, 2017). Such vigilance is stressful and consumes valuable bioenergetic resources that could otherwise be devoted to creating supportive social relationships (Maranges et al., 2021) or to caring for one’s long-term health (Ellis et al., 2009; see also Schreier & Chen, 2010). Behavioral pathways reflect the fact that unpredictable childhood environments can promote a tendency to behave in impulsive and risky ways (Del Giudice, 2009; Martinez et al., 2022). Children who experience high levels of unpredictability learn to focus on short-term rather than long-term rewards (Frankenhuis & Nettle, 2020; Frankenhuis et al., 2016) and this focus can cause people who were exposed to unpredictable childhood environments to make impulsive decisions (Ellis et al., 2012; Hartman et al., 2018; Martinez et al., 2022), and to engage in health risk behaviors such as substance use (Doom et al., 2016; Simpson et al., 2012), risky sexual behavior (Ellis et al., 2012), and unhealthy dietary choices (Maner et al., 2017). Neuroendocrine pathways include influences on corticolimbic circuitry (Gee & Cohodes, 2021; Liu & Fisher, 2022) and the hypothalamic-pituitary adrenal axis (Zakreski & Pruessner, 2019), chronic alterations of which are associated with chronic disease risk, anxiety, and mortality (Schoorlemmer et al., 2009). Future work would benefit from assessing more directly the pathways through which childhood unpredictability may affect adult health outcomes. Evidence for moderating effects was inconsistent across the two studies. Effects of unpredictability were heightened among Hispanic participants in Study 1, and among African American participants and those with relatively low income in Study 2. The presence of such moderating effects is consistent with the possibility that effects of perceived unpredictability may exacerbate the development of health problems among populations already at relatively high risk for experiencing stress associated with resource scarcity or discrimination. Compared with Study 1, which included 20% Hispanic participants, Study 2 included a higher proportion of African American participants (33% of the sample), but fewer Hispanic participants (8%). These differences in the demographic make-up of the samples may explain the inconsistent moderating effects of race and ethnicity. The two studies had similar variability in income levels, leaving open the question of whether effects are moderated by income. Limitations of the current work provide valuable avenues for future research. One limitation involves the retrospective nature of the childhood adversity measures (see Baldwin et al., 2019). Future research would benefit from recruiting other data sources (e.g., parent report) to assess the unpredictability of childhood environments, to amass developmental data with children to assess prospectively whether childhood unpredictability underlies adult health outcomes, and to leverage existing longitudinal studies to capitalize on the prospective nature of those designs (Ehrlich, 2020). In addition, while we focused on self-reported functional ability and health-related quality of life, future studies should evaluate whether childhood unpredictability is associated with clinical indicators of disability and chronic disease risk and diagnosis. Finally, it is important to note that both studies were conducted during the COVID-19 pandemic, a time during which social isolation, anxiety, and depression were high among many individuals and this, coupled with decreases in routine medical visits, could have increased health problems, as well as perceptions of health problems. Although the current work points to the importance of experiencing unpredictability in childhood, it fails to identify the specific age range in which unpredictability might exert its effects. Although some evidence suggests that such effects are especially strong in the first five to ten years of childhood (Mittal & Griskevicius, 2014; Simpson et al., 2012), ongoing debates center on the precise timing of this developmental calibration process. Future work would benefit from including repeated measurements and longitudinal designs to characterize more precisely the developmental trajectory arising from exposure to unpredictable childhood environments. Despite these limitations, this work advances theories of child adversity and health. This work also provides valuable information for the development of child interventions targeting malleable environmental risk factors that influence health. Interventions that increase the predictability and certainty of childhood environments (e.g., by increasing the consistency of a child’s daily routines) may hold potential for improving health (Miller et al., 2014; Schreier & Chen, 2010). Such interventions are also feasible: creating a sense of certainty and stability by increasing the predictability of a child’s environment may provide a relatively cost-effective and implementable means of improving public health and well-being. The current work provides a useful springboard for examining the utility of such interventions and further investigating the role of childhood unpredictability in health across the lifespan. Supplementary Information Below is the link to the electronic supplementary material.Supplementary file1 (DOCX 271 KB) Authors contribution All authors contributed substantially either to the design, conceptualization, execution, analysis, or write-up of this research. Funding Not applicable. Data availability All data and materials will be made available on OSF upon publication. Code availability All statistical code will be made available on OSF upon publication. Declarations Conflict of interest The authors did not receive support from any organization for the submitted work and no funding was received to assist with the preparation of this manuscript. The authors have no competing interests to declare that are relevant to the content of this article. Consent to participate All participants provided consent prior to participation. Consent for publication Not applicable. Ethical approval This research was approved by the FSU IRB. Human and animal rights and informed consent All procedures followed were in accordance with ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000. Informed consent was obtained from all patients for being included in the study. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Adler NE Boyce WT Chesney MA Folkman S Syme SL Socioeconomic inequalities in health: No easy solution JAMA 1993 269 3140 3145 10.1001/jama.1993.03500240084031 8505817 Baldwin JR Reuben A Newbury JB Danese A Agreement between prospective and retrospective measures of childhood maltreatment: A systematic review and meta-analysis JAMA Psychiatry 2019 76 584 593 10.1001/jamapsychiatry.2019.0097 30892562 Baram TZ Davis EP Obenaus A Sandman CA Small SL Solodkin A Stern H Fragmentation and unpredictability of early-life experience in mental disorders American Journal of Psychiatry 2012 169 9 907 915 10.1176/appi.ajp.2012.11091347 22885631 Barile JP Horner-Johnson W Krahn G Zack M Miranda D Measurement characteristics for two health-related quality of life measures in older adults: The SF-36 and the CDC Healthy Days items Disability & Health Journal 2016 9 567 574 10.1016/j.dhjo.2016.04.008 27259343 Belsky J Schlomer GL Ellis BJ Beyond cumulative risk: Distinguishing harshness and unpredictability as determinants of parenting and early life history strategy Developmental Psychology 2012 48 662 673 10.1037/a0024454 21744948 Boyce WT Ellis BJ Biological sensitivity to context: An evolutionary-developmental theory of the origins and functions of stress reactivity Development and Psychopathology 2005 17 271 301 10.1017/S0954579405050145 16761546 Bradley RH Corwyn RF Socioeconomic status and child development Annual Review of Psychology 2002 53 371 399 10.1146/annurev.psych.53.100901.135233 11752490 Brumbach BH Figueredo AJ Ellis BJ Effects of harsh and unpredictable environments in adolescence on development of life history strategies: A longitudinal test of an evolutionary model Human Nature 2009 20 25 51 10.1007/s12110-009-9059-3 20634914 Cabeza De Baca TC Wahl RA Barnett MA Figueredo AJ Ellis BJ Adversity, adaptive calibration, and health: The case of disadvantaged families Adaptive Human Behavior and Physiology 2016 2 93 115 10.1007/s40750-016-0042-z 27175327 Centers for Disease Control and Prevention. (1993). Health related quality of life scale. (https://www.cdc.gov/hrqol/methods.htm). Chen E Matthews KA Boyce WT Socioeconomic differences in children’s health: How and why do these relationships change with age? Psych Bulletin 2002 128 295 329 10.1037/0033-2909.128.2.295 Chen E Miller GE Socioeconomic status and health: Mediating and moderating factors Annual Review of Clinical Psychology 2013 9 723 749 10.1146/annurev-clinpsy-050212-185634 23245339 Del Giudice M Sex, attachment, and the development of reproductive strategies Behavioral and Brain Sciences 2009 32 1 21 10.1017/S0140525X09000016 19210806 Del Giudice M Ellis BJ Shirtcliff EA The adaptive calibration model of stress responsivity Neuroscience & Biobehavioral Reviews 2011 35 1562 1592 10.1016/j.neubiorev.2010.11.007 21145350 Doom JR Vanzomeren-Dohm AA Simpson JA Early unpredictability predicts increased adolescent externalizing behaviors and substance use: A life history perspective Development and Psychopathology 2016 28 1505 1516 10.1017/S0954579415001169 26645743 Dube SR Anda RF Felitti VJ Croft JB Edwards VJ Giles WH Growing up with parental alcohol abuse: Exposure to childhood abuse, neglect, and household dysfunction Child Abuse & Neglect 2001 25 1627 1640 10.1016/S0145-2134(01)00293-9 11814159 Dube SR Felitti VJ Dong M Giles WH Anda RF The impact of adverse childhood experiences on health problems: Evidence from four birth cohorts dating back to 1900 Preventive Medicine 2003 37 268 277 10.1016/S0091-7435(03)00123-3 12914833 Ehrlich KB How does the social world shape health across the lifespan? Insights and new directions American Psychologist 2020 75 1231 1241 10.1037/amp0000757 33382288 Ehrlich KB Miller GE Chen E Childhood adversity and adult physical health Developmental Psychopathology 2016 22 1 42 Elliott TE Renier CM Palcher JA Chronic pain, depression, and quality of life: Correlations and predictive value of the SF-36 Pain Medicine 2003 4 331 339 10.1111/j.1526-4637.2003.03040.x 14750909 Ellis BJ Del Giudice M Developmental adaptation to stress: An evolutionary perspective Annual Review of Psychology 2019 70 111 139 10.1146/annurev-psych-122216-011732 30125133 Ellis BJ Del Giudice M Dishion TJ Figueredo AJ Gray P Griskevicius V Hawley PH The evolutionary basis of risky adolescent behavior: Implications for science, policy, and practice Developmental Psychology 2012 48 598 627 10.1037/a0026220 22122473 Ellis BJ Figueredo AJ Brumach BH Schlomer GL Fundamental dimensions of environmental risk: The impact of harsh versus unpredictable environments on the evolution and development of life history strategies Human Nature 2009 20 204 268 10.1007/s12110-009-9063-7 25526958 Felitti VJ Anda RF Nordenberg D Williamson DF Spitz AM Edwards V Koss MP Marks JS Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: The adverse childhood experiences (ACE) study American Journal of Preventive Medicine 1998 14 245 328 10.1016/S0749-3797(98)00017-8 9635069 Frankenhuis WE Nettle D The strengths of people in poverty Current Directions in Psychological Science 2020 29 16 21 10.1177/0963721419881154 Frankenhuis WE Panchanathan K Nettle D Cognition in harsh and unpredictable environments Current Opinion in Psychology 2016 7 76 80 10.1016/j.copsyc.2015.08.011 Gee DG Cohodes EM Influences of caregiving on development: A sensitive period for biological embedding of predictability and safety cues Current Directions in Psychological Science 2021 30 5 376 383 10.1177/09637214211015673 34675455 Gosling SD Rentfrow PJ Swann WB Jr A very brief measure of the big five personality domains Journal of Research in Personality 2003 37 504 528 10.1016/S0092-6566(03)00046-1 Hartman S Sung S Simpson JA Schlomer GL Belsky J Decomposing environmental unpredictability in forecasting adolescent and young adult development: A two-sample study Developmental and Psychopathology 2018 30 1321 1332 10.1017/S0954579417001729 Hayes AF Introduction to mediation, moderation, and conditional process analysis: A regression-based approach 2017 Guilford Publications John OP Srivastava S Pervin LA John OP The big-five trait taxonomy: History, measurement, and theoretical perspectives Handbook of personality: Theory and research 1999 Guilford Press 102 138 Kelly JB Emery RE Children's adjustment following divorce: Risk and resilience perspectives Family Relations 2003 52 352 362 10.1111/j.1741-3729.2003.00352.x Liu S Fisher PA Early experience unpredictability in child development as a model for understanding the impact of the COVID-19 pandemic: A translational neuroscience perspective Developmental Cognitive Neuroscience 2022 54 101091 10.1016/j.dcn.2022.101091 35217299 Maner JK Dittmann A Meltzer AL McNulty JK Implications of life history strategies for obesity Proceedings of the National Academy of Sciences 2017 114 8517 8522 10.1073/pnas.1620482114 Maranges H Hasty C Maner JK Conway P The behavioral ecology of moral dilemmas: Childhood unpredictability, but not harshness, predicts less deontological and utilitarian responding Journal of Personality and Social Psychology 2021 120 1696 1719 10.1037/pspp0000368 33507783 Maranges HM Hasty CR Martinez JL Maner JK Adaptive calibration in early development. Brief measures of perceived harshness and unpredictability Adaptive Human Behavior and Physiology 2022 8 3 313 343 10.1007/s40750-022-00200-z Martinez JL Hasty C Morabito D Maranges HM Schmidt NB Maner JK Perceptions of childhood unpredictability, delay discounting, risk-taking, and adult externalizing behaviors: A life history approach Development & Psychopathology 2022 34 705 717 10.1017/S0954579421001607 35039110 McDade TW Life history theory and the immune system: Steps toward a human ecological immunity American Journal of Physical Anthropology 2003 122 100 125 10.1002/ajpa.10398 McEwen BS Stellar E Stress and the individual: Mechanisms leading to disease Archives of Internal Medicine 1993 153 2093 2101 10.1001/archinte.1993.00410180039004 8379800 McLaughlin KA Sheridan MA Beyond cumulative risk: A dimensional approach to childhood adversity Current Directions in Psychological Science 2016 25 239 245 10.1177/0963721416655883 27773969 Mielenz T Jackson E Currey S DeVellis R Callahan LF Psychometric properties of the Centers for Disease Control and Prevention health-related quality of life (CDC HRQOL) items in adults with arthritis Health and Quality of Life Outcomes 2006 4 66 10.1186/1477-7525-4-66 16995955 Miller GE Brody GH Yu T Chen E A family-oriented psychosocial intervention reduces inflammation in low-SES African American youth Proceedings of the National Academy of Sciences 2014 111 11287 11292 10.1073/pnas.1406578111 Miller GE Chen E Parker KJ Psychological stress in childhood and susceptibility to the chronic disease of aging: Moving toward a model of behavioral and biological mechanisms Psychological Bulletin 2011 137 959 997 10.1037/a0024768 21787044 Mittal C Griskevicius V Sense of control under uncertainty depends on people’s childhood environment: A life history theory approach Journal of Personality and Social Psychology 2014 107 621 637 10.1037/a0037398 25133717 Parshall MB Mapel DW Rice L Williams A O’Reilly J Predictive validity of short-form health survey [36 items] scales for chronic obstructive pulmonary disease exacerbation Heart & Lung 2008 37 356 365 10.1016/j.hrtlng.2007.09.007 18790336 Pepper GV Nettle D The behavioural constellation of deprivation: Causes and consequences Behavioral & Brain Sciences 2017 40 e314 10.1017/S0140525X1600234X 28073390 RAND Health Care. (1995). 36-item short form survey instrument (SF-36). https://www.rand.org/health-care/surveys_tools/mos/36-item-short-form/survey-instrument.html. Schoorlemmer R Peeters G van Schoor N Lips P Relationships between cortisol level, mortality, and chronic disease in older persons Clinical Endocrinology 2009 71 779 786 10.1111/j.1365-2265.2009.03552.x 19226268 Schreier HM Chen E Longitudinal relationships between family routines and biological profiles among youth with asthma Health Psychology 2010 29 82 90 10.1037/a0018311 20063939 Simpson JA Griskevicius V Kuo SI Sung S Collins WA Evolution, stress, and sensitive periods: The influence of unpredictability in early versus late childhood on sex and risky behavior Developmental Psychology 2012 48 674 686 10.1037/a0027293 22329381 Zakreski E Pruessner JC Effects of childhood trauma on the cortisol and testosterone stress response are mediated by life history strategy Psychoneuroendocrinology 2019 100 S21 S22 10.1016/j.psyneuen.2018.12.084
PMC009xxxxxx/PMC9684822.txt	==== Front J Behav Med J Behav Med Journal of Behavioral Medicine 0160-7715 1573-3521 Springer US New York 36417011 379 10.1007/s10865-022-00379-2 Article Associations between COVID-19 vaccine uptake, race/ethnicity, and political party affiliation http://orcid.org/0000-0001-6809-892X Andersen Jennifer A. [email protected] 1 Gloster Erin 2 Hall Spencer 2 Rowland Brett 2 Willis Don E. 1 Kraleti Shashank S. 3 McElfish Pearl A. 1 1 grid.411017.2 0000 0001 2151 0999 College of Medicine, University of Arkansas for Medical Sciences Northwest, 2708 S. 48th St.,, Springdale, AR 72762 USA 2 grid.411017.2 0000 0001 2151 0999 Office of Community Health and Research, University of Arkansas for Medical Sciences Northwest, 2708 S. 48th St.,, Springdale, AR 72762 USA 3 grid.241054.6 0000 0004 4687 1637 College of Medicine, University of Arkansas for Medical Sciences, 4301 W. Markham St., Little Rock, AR 72205 USA 22 11 2022 2023 46 3 525531 29 8 2022 5 11 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Despite widespread availability of vaccines, COVID-19 is a leading cause of death in the United States (US), and sociodemographic disparities in vaccine uptake remain. Race/ethnicity, partisanship, and perception of peer vaccination status are strong predictors of vaccine uptake, but research is limited among some racial/ethnic groups with small populations. The current study used an online survey to examine the relationship between these factors among a diverse sample of US adults (n = 1,674), with oversampling of racial and ethnic minorities. Respondents provided sociodemographic information and answered questions regarding COVID-19 vaccination status, political affiliation, perception of peers’ vaccination status, COVID-19 death exposure, and previous COVID-19 infection. Respondents who identified as Asian American had higher odds of being vaccinated, whereas those who identified as Black/African American or American Indian or Alaska Native (AIAN) had lower odds. Respondents who identified as Independent/Other or Republican had lower vaccination odds. Respondents who perceived anything less than nearly all of their peers were vaccinated had lower vaccination odds. Further, lack of a primary care provider, younger age, and lower educational attainment were associated with lower vaccination odds. Findings may help to determine where additional work is needed to improve vaccine uptake in the US. Results indicate the need for intentional and tailored vaccination programs in Black/African American and AIAN communities; the need to understand how media and political actors develop vaccination messaging and impact vaccine uptake; and the need for additional research on how people estimate, understand, and form decisions around peer vaccination rates. Keywords COVID-19 vaccine Vaccine uptake Racial and ethnic minorities Political affiliation Peer vaccination status Rapid Acceleration of Diagnostics (RADx)NIH 3 R01MD013852-03S2 http://dx.doi.org/10.13039/100006108 National Center for Advancing Translational Sciences UL1 TR003107 Community Engagement Alliance (CEAL) Against COVID-19 Disparities NIH 10T2HL156812-01 issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction Despite widespread availability of COVID-19 vaccines, COVID-19 is a leading cause of death in the United States (US) (Ahmad & Anderson, 2021). Although vaccines have helped to reduce morbidity and mortality, sociodemographic disparities in vaccine uptake remain, particularly among racial and ethnic groups who have already experienced disproportionately higher rates of COVID-19 infection and death (Magesh et al., 2022; Ndugga et al., 2022; Reitsma et al., 2022). Research has consistently demonstrated higher rates of vaccine hesitancy among Black/African American adults, who currently have the lowest COVID-19 vaccination rates in the US compared with other racial/ethnic groups (Daly et al., 2021; Ndugga et al., 2022; Reitsma et al., 2022; Willis et al., 2021). Studies involving other racial and ethnic minorities disproportionately affected by the COVID-19 pandemic, including Asian American, Native Hawaiian or Pacific Islander (NHPI), and American Indian or Alaska Native (AIAN) individuals, are lacking or have provided mixed findings. Where data was available, studies found that AIAN have the second-highest vaccination rate among racial/ethnic minorities in the US (Foxworth et al., 2021; Hill & Artiga, 2021); however, this finding is not often reported in vaccine uptake literature, most likely due to combining multiple, smaller racial and ethnic minority populations into singular groups with the label “other race/ethnicity.” Studies have noted similarly high vaccination rates among Asian American populations, with Asian American communities having the highest COVID-19 vaccine uptake rates among racial/ethnic minorities in the US (Niño et al., 2021), but these studies did not distinguish between sub-populations within the racial/ethnic group. For example, one such study combined Asian (6.1% of the US population) with NHPI (0.3% of the US population) (Niño et al., 2021). Data aggregation may be masking nuances in COVID-19 vaccine uptake findings (Ta Park et al., 2021). Although racial/ethnic health disparities in vaccine uptake still exist, they have narrowed over time (Daly et al., 2021), and other sociodemographic gaps in vaccine uptake have widened. One of these increasingly widening gaps is the divide in political party affiliation in relation to vaccine uptake. Politicization and polarization in early COVID-19 media coverage may have contributed to polarization in US attitudes about the COVID-19 pandemic (Hart et al., 2020), extending to attitudes about COVID-19 vaccines. Recent studies indicate that political partisanship has become a stronger predictor of vaccination status than factors such as age, race, education, or insurance status, with Republicans making up a disproportionate share of those who have not received the COVID-19 vaccine (Kirzinger et al., 2021). Other studies have indicated that political ideology has a direct effect on vaccine attitudes, with conservative respondents being less likely to express pro-vaccination beliefs (Baumgaertner, 2022) and more likely to endorse vaccine misinformation (Motta, 2021). Further complicating the disparities in vaccine uptake by race/ethnicity and political affiliation is the influence of peers on vaccine uptake. A study of California prison custody and health care staff provided evidence of lower vaccine uptake among staff who live and work among primarily unvaccinated populations (Prince et al., 2022). Additionally, a study of undergraduate students from a large public university in the northwest US illustrated that those who perceived more of their peers would choose to be vaccinated against influenza or COVID-19 reported being more likely to choose vaccination for themselves (Abdallah & Lee, 2021). Research on influenza vaccination finds that vaccination is more likely among individuals who perceive the majority of the people around them as wanting to be vaccinated (Quinn et al., 2017). Given the potential for underestimating the vaccination behaviors of others (Abdallah & Lee, 2021), especially among those in minoritized populations or in environments where political partisanship is especially salient, perceptions of low peer vaccination may further lower vaccine uptake. Considering that race/ethnicity, partisanship, and perception of peer vaccination status have been found to be strong predictors of vaccine uptake, and that there is limited research among some racial/ethnic groups with small populations, the current study sought to examine the relationship between these factors among a diverse sample of US adults. Providing a nuanced and specific understanding of the role these factors play in vaccine uptake may help to provide more detailed, targeted, and specific vaccine messaging strategies to encourage COVID-19 vaccination uptake among unvaccinated populations. Methods Invitations to participate in an online survey were emailed to individuals in an online opt-in panel of individuals managed by 4media Group. The survey was available in both English and Spanish. The email invitation included the following information about the study: (1) the estimated study duration (10 min); (2) potential risks and benefits; (3) the voluntary nature of participation; and (4) confidentiality of responses. Respondents indicated consent by agreeing to participate in the survey. A total of 2,022 US adults were recruited between September 7, 2021 and October 3, 2021. The institutional review board for the protection of human subjects at the University of Arkansas for Medical Sciences (IRB #263020) approved the study procedures. We oversampled Asian American, Black/African American, Hispanic/Latino, AIAN, and NHPI individuals. This oversampling was necessary to avoid aggregation of racial and ethnic groups, which often obscures diverse groups, experiences, and attitudes (Chang et al., 2020; Gee et al., 2022). The random iterative method (Mercer et al., January 26, 2018.) was used to weight the data to be representative of the US population across key demographic variables including gender (men, women, non-binary), race/ethnicity, and age (18–24, 25–34, 35–44, 45–54, 55–64, 65+). The sample was limited to respondents who completed the entire survey. Of the 2,022 adult respondents, 1,674 respondents are included in the final analytic sample. Political affiliation (9.5%), knowing someone who died of COVID-19 (4.4%), and previous COVID-19 infection (3.4%) had the highest percentage of missing responses. Measures Vaccination status Vaccination status was determined by the response to the question, “Have you received a COVID-19 vaccine?” with a dichotomous response option of yes or no. Political affiliation Political affiliation was determined by the response to the question, “Generally speaking, do you consider yourself as a…?” with response options of Democrat, Republican, Independent, or Other. Independent and Other categories were combined due to the low number of responses. Perception of peer vaccination status Respondents were asked of the people close to them, how many they believed had been vaccinated. Response options included that they believed very few people, some people but not many, many people, or nearly all people they know had been vaccinated. COVID-19 related factors Respondents were asked if they had previously been infected by COVID-19 (yes/no) or if they know anyone who had died from COVID-19 (yes/no). Sociodemographic characteristics Sociodemographic information collected included age, gender, and education. Age (18–34, 35–44, and 45+) and gender (man, woman, non-binary, or self-described) were categorical variables; however, only a few of the respondents selected a non-binary gender or self-described, and therefore, the analytic sample included only self-identified men and women. Education was measured by asking respondents their highest degree or level of school completed; respondents with less than high school and only some high school were combined with high school graduates, and those with a bachelor’s degree or higher were similarly combined due to low frequency of responses for some education levels. Employment status was dichotomized to those working for wages and those who were not, such as students, retirees, and those temporarily out of work. Respondents were also asked to report their insurance status (insured/uninsured) and whether they had a primary care provider (yes/no). Analysis Using the appropriate survey weights, descriptive statistics (frequencies and proportions) were used to characterize the sample. Due to the low number of unvaccinated respondents, multivariate complementary log-log regression was used to determine the odds ratios (OR) for the variables of interest. Analysis was completed using STATA 17.0, and a p value of 0.05 or less was considered statistically significant. Results Sample characteristics Table 1 reports the weighted sample characteristics. 73% of the sample reported having received at least one dose of the COVID-19 vaccine. 54% of the participants were 45 or older, 30% were between the ages of 18 and 34, and 16% were between the ages of 35 and 44. The sample was evenly split between men and women. 38% of the sample had a bachelor’s degree or more, and 28% had a high school education or less. The majority of the sample (58%) were unemployed at the time of the survey; however, 87% were insured, and 81% had a primary care provider. A quarter of participants reported knowing someone who died of COVID-19, and the majority (82%) had not been previously infected with COVID-19. Table 1 Weighted Proportions of Sample Characteristics, N = 1,674 Proportion SE [95% CI] Vaccination status Not vaccinated 0.27 0.01 [0.25, 0.29] Vaccinated 0.73 0.01 [0.71, 0.75] Age 18–34 0.30 0.01 [0.28, 0.32] 35–44 0.16 0.01 [0.14, 0.18] 45+ 0.54 0.01 [0.52, 0.57] Gender Men 0.50 0.01 [0.48, 0.53] Women 0.50 0.01 [0.47, 0.53] Race/Ethnicity Asian American 0.10 0.01 [0.09, 0.11] Black/African American 0.20 0.01 [0.18, 0.22] Hispanic/Latino 0.20 0.01 [0.18, 0.22] AIAN 0.05 0.004 [0.04, 0.06] NHPI 0.05 0.004 [0.04, 0.06] White 0.40 0.01 [0.37, 0.43] Education High school or less 0.28 0.01 [0.26, 0.31] Some college/No degree 0.21 0.01 [0.19, 0.24] Associate 0.13 0.01 [0.11, 0.14] Bachelor’s or graduate 0.38 0.01 [0.35, 0.40] Employment Not employed for wages 0.58 0.01 [0.56, 0.61] Employed for wages 0.42 0.01 [0.39, 0.44] Insurance status Uninsured 0.13 0.01 [0.12, 0.15] Insured 0.87 0.01 [0.85, 0.89] Has a primary care provider Yes 0.81 0.01 [0.79, 0.83] No 0.19 0.01 [0.17, 0.21] Do you know someone who has died from COVID-19? No 0.75 0.01 [0.73, 0.77] Yes 0.25 0.01 [0.23, 0.27] Have you had COVID-19? Have not had COVID-19 0.82 0.01 [0.80, 0.84] Had COVID-19 0.18 0.01 [0.16, 0.20] Political affiliation Democrat 0.45 0.01 [0.42, 0.47] Independent/Other 0.32 0.01 [0.30, 0.35] Republican 0.23 0.01 [0.21, 0.26] How many people do you know who have been vaccinated? Very few 0.10 0.01 [0.09, 0.12] Some but not many 0.23 0.01 [0.22, 0.26] Many 0.37 0.01 [0.35, 0.39] Nearly all 0.29 0.01 [0.27, 0.31] Notes: AIAN = American Indian or Alaska Native; CI = confidence interval; NHPI = Native Hawaiian or Pacific Islander; SE = standard error. 40% of the sample identified as White, 20% identified as Black/African American, and 20% identified as Hispanic/Latino. 10% of the sample identified as Asian American, 5% of the sample identified as NHPI, and an additional 5% identified as AIAN. 45% of the sample identified as Democrat, 23% identified as Republican, and 32% identified as Independent/Other. 10% of the sample reported they perceived very few people they know had been vaccinated, 23% reported some but not many had been vaccinated, 37% said many had been vaccinated, and 29% stated that nearly all of the people they know had been vaccinated. Table 2 reports the results of the multivariate log-log regression exploring the odds of vaccination among respondents. Adults who were 45 or older had 1.35 times higher odds of being vaccinated (p = .006) than those between the ages of 18 and 34. Odds of vaccination increased as educational attainment increased; respondents with an associate degree had 1.31 times higher odds of vaccination (p = .049), and those with a bachelor’s degree or higher had 1.41 times higher odds of vaccination (p = .003) than those with high school education or less. Respondents without a primary care provider had lower odds of being vaccinated (OR = 0.68, p = .002). Respondents who reported knowing someone who died from COVID-19 had higher odds of being vaccinated (OR = 1.40, p = .001); however, those who had previously been infected with COVID-19 had lower odds of being vaccinated (OR = 0.75, p = .011). There were no statistical differences in the odds of vaccination by gender, employment, or insurance status. Table 2 Multivariate Complementary Log-Log Regression of the Odds of Vaccination, N = 1,674 OR SE [95% CI] p Age (ref = 18–34) 35–44 1.03 0.13 [0.81, 1.31] 0.819 45+ 1.35 0.15 [1.09, 1.67] 0.006 Women 1.08 0.09 [0.92, 1.27] 0.363 Education (ref = High school or less) Some college/No degree 1.07 0.13 [0.85, 1.35] 0.547 Associate 1.31 0.18 [1.00, 1.71] 0.049 Bachelor’s or graduate 1.41 0.16 [1.12, 1.78] 0.003 Employed for wages 1.14 0.10 [0.95, 1.36] 0.155 Insured 1.07 0.15 [0.81, 1.43] 0.598 No primary care provider 0.68 0.08 [0.54, 0.87] 0.002 Knows someone who died of COVID-19 1.40 0.14 [1.15, 1.71] 0.001 Had COVID-19 0.75 0.09 [0.60, 0.94] 0.011 Race/Ethnicity (ref = White) Asian American 1.49 0.21 [1.13, 1.98] 0.005 Black/African American 0.70 0.08 [0.55, 0.88] 0.002 Hispanic/Latino 0.88 0.11 [0.70. 1.11] 0.29 AIAN 0.26 0.09 [0.47, 0.83] 0.001 NHPI 0.90 0.15 [0.65, 1.23] 0.50 Political affiliation (ref = Democrat) Independent/Other 0.64 0.06 [0.53, 0.77] < 0.001 Republican 0.63 0.08 [0.50, 0.80] < 0.001 How many people do you know who have been vaccinated? (ref = Nearly all) Very few 0.16 0.03 [0.11, 0.23] < 0.001 Some but not many 0.36 0.04 [0.29, 0.46] < 0.001 Many 0.53 0.06 [0.43, 0.65] < 0.001 Constant 2.58 0.59 [1.65, 4.03] < 0.001 Notes: AIAN = American Indian or Alaska Native; CI = confidence internal; NHPI = Native Hawaiian or Pacific Islander; OR = odds ratio; SE = standard error. Compared to respondents who identified as White, respondents who identified as Asian had 1.49 times higher odds of vaccination (p = .005), whereas odds of vaccination decreased by 30% for respondents who identified as Black/African American (p = .002) and by 74% for those who identified as AIAN (p = .001). Respondents who identified as Independent/Other (OR = 0.64, p < .001) or Republican (OR = 0.63, p < .001) had lower odds of vaccination compared to respondents who identified as Democrat. The odds of vaccination decreased for respondents who stated many (OR = 0.53, p < .001), some but not many (OR = 0.36, p < .001), or very few (OR = 0.16, p < .001) of the people they know were vaccinated compared with respondents who perceived nearly all of the people they know have been vaccinated. Discussion The results of our study illustrate the influence of race/ethnicity, political affiliation, and perceptions of peer vaccination status on vaccination status. Respondents who identified as Asian American had higher odds of reporting being vaccinated, whereas those who identified as Black/African American or AIAN had lower odds of being vaccinated. Further, respondents who identified as Independent/Other or Republican had lower odds of being vaccinated. Respondents who perceived anything less than nearly all of their peers were vaccinated had lower odds of vaccination. The findings of this study are an important picture of where more work is needed to improve vaccination uptake in the US. Sociodemographic disparities in vaccine uptake remain, including by age and education. Certain racial and ethnic groups have experienced disproportionately higher rates of COVID-19 infection and death (Magesh et al., 2022; Ndugga et al., 2022; Reitsma et al., 2022). Prior work has demonstrated that Black/African American adults have the lowest COVID-19 vaccination rates in the US compared to other races/ethnicities (Daly et al., 2021; Ndugga et al., 2022; Reitsma et al., 2022; Willis et al., 2021). The results of this study support prior research demonstrating the continued importance of addressing the sources of vaccine hesitancy in the Black/African American community to increase vaccination rates, including experiences of discrimination (Willis et al., 2022). Further, our study is one of the first to allow for the disaggregation of race/ethnicity into smaller categories to understand vaccine uptake. Our findings support previous work showing that those who identify as Asian American have the highest COVID-19 vaccine uptake rates among racial/ethnic minorities in the US (Niño et al., 2021). Previous studies have found that AIAN have the second-highest vaccination rate among racial/ethnic minorities in the US (Foxworth et al., 2021; Hill & Artiga, 2021); however, our findings show respondents who identified as part of the AIAN population had lower odds of vaccination than those who identified as White. It is difficult to know why our results are different from other studies. It is possible that respondents living in the community setting were disconnected from the education and resources provided by Indian Health Services, increasing vaccine hesitancy and reducing vaccine uptake. Additionally, although other studies have found members of the NHPI community to be more vaccine hesitant than other Asian American groups (Ta Park et al., 2021), our results show that those who identify as NHPI do not have statistically different odds of vaccination than their White counterparts. Our findings support the need to ensure study designs include large enough sample sizes to disaggregate racial/ethnic groups during analysis. Further, the findings indicate the need for more intentional and tailored vaccination programs in Black/African American and AIAN communities. The results show a divide in political party affiliation in relation to vaccine uptake. The politicization of COVID-19 does seem to have contributed to polarization in US attitudes about COVID-19 vaccines, reducing the odds of vaccination in those who identify as Republican or as Independent/Other. Studies have shown political partisanship has become a stronger predictor of vaccination status than factors such as age, race, or education (Kirzinger et al., 2021); however, our results show that these factors still influence vaccine uptake even when accounting for political affiliation. Still, political identity has a direct effect on vaccine attitudes. Further work is needed to understand how political affiliation influences vaccine uptake through its impact on perception as well as the uptake of trusted information in an increasingly fractured (and fractious) media environment (Bartels, 2002). This work includes understanding how agenda setting (McCombs et al., 2014) and framing (Tewksbury & Scheufele, 2009) are utilized by political figures and news media when discussing COVID-19 vaccination and COVID-19 infection. Additionally, there is a need for public health officials to find means to convey information to populations who may be hesitant to accept their recommendations. Similar to prior studies (Abdallah & Lee, 2021; Prince et al., 2022), our results provide evidence of lower vaccine uptake among those who perceived their peers would not choose to be vaccinated against COVID-19. Given the potential for underestimating the vaccination behaviors of others (Abdallah & Lee, 2021), additional work is needed to understand how people estimate the vaccination rate among their peers and to determine the accuracy of these assumptions. Further, lack of a primary care provider, younger age, and lower educational attainment were associated with lower odds of vaccination. These results support prior research showing that younger adults, adults with lower levels of educational attainment, and those without a primary care provider are less likely to be vaccinated (McElfish et al., 2022; Wang et al., 2021). There are limitations to keep in mind while interpreting these results. The methods used to develop the sample for this study were not random due to oversampling of minoritized groups, limiting the generalizability of this study to the wider population. Additionally, the study used cross-sectional data, and therefore, we are unable to establish causal relationships. Despite their many advantages, online surveys often suffer from low participation among minoritized racial and ethnic groups. We anticipated this limitation and addressed it by oversampling minoritized racial and ethnic groups in large numbers to ensure their representation in the study. We rely on self-report for vaccination status, political affiliation, and perception of peer vaccination, which does leave open the potential for bias. We attempted to mitigate bias by using validated measures. Conclusion The findings of this study are an important part of determining where additional work is needed to improve vaccination uptake in the US. It is one of the only studies with an oversample of racial/ethnic minorities, allowing for a more nuanced picture of vaccine uptake. The results indicate the need for intentional and tailored vaccination programs in Black/African American and AIAN communities. Further, there is a need to understand how the media and political actors use agenda setting and framing in developing messaging related to vaccination and how this messaging relates to vaccine uptake. Finally, there is a need for additional research to understand how people estimate the vaccination rate among their peers, the accuracy of these assumptions, and how those assumptions feed into vaccine uptake. Authors’ Contributions Jennifer A. Andersen: Conceptualization, Methodology, Validation, Formal Analysis, Writing - Original Draft, Writing - Review & Editing, Supervision; Erin Gloster: Conceptualization, Writing - Original Draft, Writing - Review & Editing; Spencer Hall: Validation, Formal Analysis, Writing - Review & Editing; Brett Rowland: Conceptualization, Writing - Original Draft, Writing - Review & Editing; Don E. Willis: Investigation, Data Curation, Writing - Review & Editing, Project Administration; Shashank S. Kraleti: Writing - Review & Editing; Pearl A. McElfish: Writing - Review & Editing, Supervision, Funding Acquisition Funding Support was provided by the Rapid Acceleration of Diagnostics (RADx) (NIH 3 R01MD013852-03S2); University of Arkansas for Medical Sciences funding awarded through the National Center for Research Resources and National Center for Advancing Translational Sciences of the National Institutes of Health (NIH) (UL1 TR003107); and Community Engagement Alliance (CEAL) Against COVID-19 Disparities (NIH 10T2HL156812-01). The content is solely the responsibility of the authors and does not necessarily represent the official views of the funders. Data Availability The deidentified data underlying the results presented in this study may be made available upon reasonable request from the corresponding author, Pearl A. McElfish, at [email protected]. Code Availability N/A. Declarations Conflict of Interest The authors declared no conflicts of interest. Ethics Approval The institutional review board for the protection of human subjects at the University of Arkansas for Medical Sciences (IRB #263020) approved the study procedures. Consent to Participate Invitations to participate in an online survey were emailed to individuals in an online registry of research volunteers. The email invitation included the following information about the study: (1) the estimated study duration (10 min); (2) potential risks and benefits; (3) the voluntary nature of participation; and (4) confidentiality of responses. Respondents indicated consent by agreeing to participate in the survey. Consent for Publication N/A. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Abdallah DA Lee CM Social norms and vaccine uptake: College students’ COVID vaccination intentions, attitudes, and estimated peer norms and comparisons with influenza vaccine Vaccine 2021 39 15 2060 2067 10.1016/j.vaccine.2021.03.018 33741191 Ahmad FB Anderson RN The Leading Causes of Death in the US for 2020 Journal Of The American Medical Association 2021 325 18 1829 1830 10.1001/jama.2021.5469 33787821 Bartels L Beyond the Running Tally: Partisan Bias in Political Perceptions Political Behavior 2002 24 2 117 150 10.1023/A:1021226224601 Baumgaertner B Carlisle JE Justwan F The influence of political ideology and trust on willingness to vaccinate PLOS One 2022 13 1 e0191728 10.1371/journal.pone.0191728 Chang R Penaia C Thomas K Count Native Hawaiian And Pacific Islanders in COVID-19 Data-It’s An OMB Mandate Health Affairs Blog 2020 10.1377/hblog20200825.671245/full/ Daly M Jones A Robinson E Public Trust and Willingness to Vaccinate against COVID-19 in the US from October 14, 2020 to March 29, 2021 Journal of the American Medical Association 2021 325 23 2397 10.1001/jama.2021.8246 34028495 Foxworth, R., Redvers, N., Moreno, M., Lopez-Carmen, V., Sanchez, G., & Shultz, J. (2021). Covid-19 Vaccination in American Indians and Alaska Natives — Lessons from Effective Community Responses. The New England Journal of Medicine, 385, 2403–2406. 10.1056/NEJMp2113296 Gee G Morey B Bacong A Doan T Penaia C 2022 Considerations of Racism and Data Equity Among Asian Americans 10.1007/s40471-022-00283-y Hart P Chinn S Soroka S Politicization and Polarization in COVID-19 News Coverage: [research-article] Science Communication 2020 42 5 679 697 10.1177/1075547020950735 Hill, L., & Artiga, S. (2021). COVID-19 Vaccination among American Indian and Alaska Native People. KFF. April 9, 2021. Retrieved May 5, 2022 from https://www.kff.org/racial-equity-and-health-policy/issue-brief/covid-19-vaccination-american-indian-alaska-native-people/ Kirzinger, A., Kearney, A., Hamel, L., & Brodie, M. (2021). KFF COVID-19 Vaccine Monitor: The Increasing Importance of Partisanship in Predicting COVID-19 Vaccination Status. KFF. November 16, 2021. Retrieved May 5, 2022 from https://www.kff.org/coronavirus-covid-19/poll-finding/importance-of-partisanship-predicting-vaccination-status/ Magesh S John D Li W Li Y Mattingly-app A Jain S Ongkeko W Disparities in COVID-19 Outcomes by Race, Ethnicity, and Socioeconomic Status: A Systematic Review and Meta-analysis JAMA Network Open 2022 4 11 e2134147 10.1001/jamanetworkopen.2021.34147 McCombs ME Shaw DL Weaver DH New directions in agenda-setting theory and research Mass communication and society 2014 17 6 781 802 10.1080/15205436.2014.964871 McElfish PA Selig JP Scott AJ Rowland B Willis DE Reece S Macechko MD Associations between 5-year influenza vaccination and sociodemographic factors and healthcare access among Arkansans Vaccine 2022 40 27 3727 3731 10.1016/j.vaccine.2022.05.031 35606233 Mercer, A., Lau, A., & Kennedy, C. (2018.). How different weighting methods work. Pew Research Center Methods. January 26, 2018. Retrieved April 12, 2022 from https://www.pewresearch.org/methods/2018/01/26/how-different-weighting-methods-work/. Motta, M. (2021). Republicans, Not Democrats, Are More Likely to Endorse Anti-Vaccine Misinformation. American Politics Research, 49(5), 428-438. https://doi.org/10.1177_1532673X211022639. Ndugga, N., Hill, L., Artiga, S., & Haldar, S. (2022). Latest Data on COVID-19 Vaccinations by Race/Ethnicity. KFF. April 7, 2022. Retrieved April 12, 2022 from https://www.kff.org/coronavirus-covid-19/issue-brief/latest-data-on-covid-19-vaccinations-by-race-ethnicity/. Niño MD Hearne BN Cai T Trajectories of COVID-19 vaccine intentions among U.S. adults: The role of race and ethnicity SSM Popul Health 2021 15 100824 10.1016/j.ssmph.2021.100824 34075337 Prince, L., Long, E., Studdert, D. M., Leidner, D., Chin, E. T., Andrews, J. R., & Goldhaber-Fiebert, J. D. (2022). Uptake of COVID-19 Vaccination Among Frontline Workers in California State Prisons. JAMA Health Forum, 3(3): e220099. https://doi.org/10.1001/jamahealthforum.2022.0099 Quinn SC Hilyard KM Jamison AM An J Hancock GR Musa D Freimuth VS The influence of social norms on flu vaccination among African American and White adults Health Education Research 2017 32 6 473 486 10.1093/her/cyx070 29220514 Reitsma M Goldhaber-Fiebert J Salomon J Quantifying and Benchmarking Disparities in COVID-19 Vaccination Rates by Race and Ethnicity JAMA Network Open 2022 4 10 e2130343 10.1001/jamanetworkopen.2021.30343 Ta Park VM Dougan M Meyer OL Nam B Tzuang M Park LG Tsoh JY Vaccine willingness: Findings from the COVID-19 effects on the mental and physical health of Asian Americans & Pacific Islanders survey study (COMPASS) Prev Med Rep 2021 23 101480 10.1016/j.pmedr.2021.101480 34307000 Tewksbury, D., & Scheufele, D. A. (2009). News framing theory and research. Media Effects (pp. 33–49). Routledge. Wang Q Yang L Jin H Lin L Vaccination against COVID-19: A systematic review and meta-analysis of acceptability and its predictors Preventive medicine 2021 150 106694 10.1016/j.ypmed.2021.106694 34171345 Willis DE Andersen JA Bryant-Moore K Selig JP Long CR Felix HC McElfish PA COVID-19 vaccine hesitancy: Race/ethnicity, trust, and fear Clinical And Translational Science 2021 10.1111/cts.13077 34213073 Willis, D. E., Andersen, J. A., Montgomery, B. E., Selig, J. P., Shah, S. K., Zaller, N., & McElfish, P. A. (2022). COVID-19 Vaccine Hesitancy and Experiences of Discrimination Among Black Adults. Journal of Racial and Ethnic Health Disparities, 1–10. https://doi.org/10.1007/s40615-022-01290-x
PMC009xxxxxx/PMC9684848.txt	==== Front Hydrobiologia Hydrobiologia Hydrobiologia 0018-8158 1573-5117 Springer International Publishing Cham 36466299 5092 10.1007/s10750-022-05092-4 Advances in Cichlid Research V Differences among reciprocal hybrids of Labeotropheus http://orcid.org/0000-0003-0748-1241 Pauers Michael J. [email protected] 123 Hoffmann Jacob 2 Ackley Leah Jiang-Bo 4 1 grid.295546.9 0000 0001 0941 8356 Section of Vertebrate Zoology, Milwaukee Public Museum, 800 W. Wells Street, Milwaukee, WI USA 2 grid.267468.9 0000 0001 0695 7223 Department of Mathematics and Natural Science, University of Wisconsin-Milwaukee at Waukesha, 1500 N. University Drive, Waukesha, WI USA 3 grid.267468.9 0000 0001 0695 7223 School of Freshwater Science, University of Wisconsin-Milwaukee, 600 E. Greenfield Avenue, Milwaukee, WI USA 4 grid.267468.9 0000 0001 0695 7223 Department of Biological Sciences, University of Wisconsin-Milwaukee, 2900 N. Maryland Avenue, Milwaukee, WI USA 22 11 2022 2023 850 10-11 21492164 19 3 2022 4 11 2022 12 11 2022 © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Current evidence suggests that hybridization played a crucial role in the early evolution and diversification of the species flocks of cichlid fishes in the African Great Lakes. Nonetheless, evidence for hybridization in the extant cichlid fauna is scant, suggesting that hybridization is rare in the modern era, perhaps enforced by natural or sexual selection acting against F1 hybrids. Additionally, most experimental studies of hybridization perform a hybrid cross in one direction, ignoring the reciprocal hybrid. In this study, we perform reciprocal crosses between sympatric congeners from Lake Malaŵi, Labeotropheus fuelleborni and L. trewavasae, in order to compare the body shape and coloration of males of both of these hybrids, as well as to examine how these hybrids fare during both inter- and intrasexual interactions. We found that L. trewavasae-sired hybrid males are intermediate to the parental species both morphologically and chromatically, while the reciprocal L. fuelleborni-sired hybrids are likely transgressive hybrids. Males of these transgressive hybrids also fare poorly during our mate choice experiments. While female L. trewavasae reject them as possible mates, male L. trewavasae do not make a distinction between them and conspecific males. Selection against transgressive F1 hybrids as observed in our crossing experiments may help explain why contemporary hybridization in Lake Malaŵi cichlids appears to be rare. Supplementary Information The online version contains supplementary material available at 10.1007/s10750-022-05092-4. Keywords Cichlids Lake Malaŵi Hybridization Transgressive phenotype Mate choice Labeotropheus issue-copyright-statement© Springer Nature Switzerland AG 2023 ==== Body pmcIntroduction Until recently, hybridization was not viewed as a significant source of adaptive variation in animals. This is partially due to the long-standing view that hybridization acts as a destructive force, leading to maladapted “dead ends,” but also due to the fact that there were very few convincing examples of adaptive introgression in animals (Mayr, 1963; Stelkens et al., 2009; Hedrick, 2013). Some of the best recent evidence for this phenomenon in vertebrates comes from the radiations of cichlid fishes in the African Great Lakes (e.g., Gante et al., 2016; Koblmuller et al., 2017; Meyer et al., 2017). These fishes represent the largest and most diverse radiations of vertebrate animals in the world, and have been rich study systems for evolutionary biologists, providing insights into speciation, adaptive radiation, and the role sexual selection can play in both of these processes (Barlow, 2000; Kornfield & Smith, 2000). Experiments involving controlled hybridization between species have provided evidence of morphological (e.g., McElroy & Kornfield, 1993; Albertson & Kocher, 2001; Stelkens et al., 2009), chromatic (e.g., Brzozowski et al., 2014; Albertson et al., 2014; Selz et al., 2014a), behavioral (Feller et al., 2020), and ecological (Selz & Seehausen, 2019) novelty. A study of hybrid novelty using species thought to be ancestral to the extant radiations in Lakes Tanganyika, Malaŵi, and Victoria found that inbred F2 individuals had a significantly increased range of morphological variation compared to that of both the parental and F1 generations (Selz et al., 2014b). This finding indicates that hybridization, far from constraining evolution, could be an important source of phenotypic novelty, especially under the ecological and environmental conditions in which these radiations occurred (e.g., Danley et al., 2012; Ivory et al., 2016; Santos-Santos et al., 2021). For example, after finding geological evidence of significant lake level fluctuations throughout the history of the Lake Malaŵi basin, Ivory et al. (2016) hypothesize that hybridization during times when the lake was shallow (“green lake” conditions) was an important source of phenotypic novelty that helped the cichlid flock radiate into the larger array of habitats and trophic niches available when lake levels subsequently rose (“blue lake” conditions), a scenario that has significant phylogenetic support (Genner & Turner, 2012, 2015). While the above-listed studies powerfully demonstrate how hybridization could act to produce phenotypic variation during the early stages of adaptive radiation in the cichlids of the African Great Lakes, they do not directly address the fate of hybrids in the extant cichlid communities of these lakes. Pauers et al. (2018) found that F1 hybrids of Labeotropheus fuelleborni and L. trewavasae were less efficient feeders than either of the parental species, leading to the expectation that such hybrids would not be successful in the wild. Additionally, many of these species are notoriously assortative with regards to mate choice, except under anthropogenically altered conditions (Seehausen et al., 1997; Egger et al., 2012), and evidence of hybridization in the wild is exceedingly rare (Stauffer et al., 1996; Smith et al., 2003). Furthermore, F1 hybrids are uncommon in the extant lacustrine radiations, and are unlikely to have much reproductive success (Crapon de Caprona, 1986; Ribbink, 1990). The fate of hybrid cichlids during sexual selection has not often been studied. In the few available studies examining patterns of mate choice involving hybrids (e.g., Svensson et al., 2011, 2017; Selz et al., 2014a), only female choice, examined post hoc via molecular genetic assessment of parentage, was evaluated; assessments of female mate choice behavior, via receptive responses or numbers of visits (e.g., Pauers et al., 2010; Pauers & Grudnowski, 2022) have rarely been conducted (e.g., Haesler & Seehausen, 2005). While more involved and time-consuming to evaluate, direct observations of courtship and receptive behavior are important due to their potential additional insights on the degree of behavioral resistance to introgression (e.g., Barlow, 2000, 2002; Coyne & Orr, 2004). Additionally, studies of intrasexual aggression, comparing the responses of territorial males to conspecific and hybrid males, have not been conducted. Given the importance of territory acquisition to male fitness for many of these species (Ribbink, 1990; Barlow, 1993; Rometsch et al., 2021), exploring this would provide valuable insights into how hybrid males would fare in a natural population. Also missing from current studies of hybridization in cichlids are comparisons of F1 offspring produced via reciprocal crosses between the parent species. In the relatively few studies in which reciprocal crosses were made, the resulting hybrid progeny were pooled in the subsequent analyses, thus obscuring their parentage (e.g., Husemann et al., 2017). Given the roles sexual conflict and chromosomal sex determination play in determining the phenotype (e.g., Roberts et al., 2009), it seems especially important to compare hybrid offspring from reciprocal crosses. The genus Labeotropheus Ahl 1927 is a small genus of haplochromine cichlids endemic to Lake Malaŵi, the species of which have been crucial in studies of the role of hybridization in the evolution of phenotypic novelty this species flock (e.g., Albertson & Kocher, 2001; Albertson et al., 2014; Concannon & Albertson, 2015). Hybrids of Labeotropheus fuelleborni, in particular, have been used to elucidate both evolutionary development and adaptive introgression in numerous phenotypic traits. In the above-mentioned study of feeding performance in hybrid Labeotropheus, Pauers et al. (2018) produced experimental F1 hybrids of Labeotropheus by crossing male L. trewavasae with female L. fuelleborni, but did not produce reciprocal hybrids. These hybrids, although they had a distinct body shape, were most morphologically similar to the maternal species, L. fuelleborni, and the color pattern of the male hybrids was most similar to that of male L. fuelleborni (Pauers et al., 2018; Pauers, pers. obsv.). We thus wanted to conduct a comparative study of body shape and male coloration in the parental species and their reciprocal hybrids; we were especially curious whether such L. fuelleborni-sired hybrids would also be most phenotypically similar to their maternal species, or if they would display a different, perhaps transgressive, morphological and chromatic phenotype. Transgressive hybrids, those that have a phenotype outside of the combined range of their parental species, are of particular interest to evolutionary biologists, as they represent a potential source of adaptive novelty (Holzman & Hulsey, 2017; Husemann et al., 2017). Additionally, we were interested in how these hybrids would fare in behavioral contexts, specifically intra- and inter-sexual selection. Methods Experimental animals Wild caught adult specimens of Labeotropheus fuelleborni and L. trewavasae were obtained from a reputable Malaŵi-based exporter of cichlid fishes (Stuart M. Grant, Ltd.); both species were captured at the Chidunga Rocks in southwestern Lake Malaŵi. Twenty individuals of each species were obtained, ten of each sex. These adults were segregated by species and sex into four separate 160 l aquaria. Fishes were fed to satiation daily with a mixture of spirulina flake food (e.g., Formula Two; Ocean Nutrition, Newark, CA, USA), cichlid pellets (e.g., Hikari Cichlid Excel; Kyorin Co., Ltd., Hyogo, Japan), and a variety of frozen foods (e.g., bloodworms, brine shrimp; various manufacturers). Water temperature was maintained at 25°C, and water quality was maintained using standard box filters and biweekly 50% water changes. Intraspecific F1 individuals of both species were produced by moving randomly selected groups of adults (1–3 males with 2–5 females) into separate 160 l aquaria, which were maintained as described above. The breeding groups of fishes were fed to satiation daily with the assortment of foods provided to the fishes in the stock tanks. Mouthbrooding females were isolated in separate aquaria (80 l or 120 l) until their fry were released at about 21 days post-fertilization. Using this same breeding and rearing protocol, two different hybrids were produced via reciprocal crosses between L. fuelleborni and L. trewavasae by pairing 1–3 males of one species with 2–5 females of the other. All F1 individuals, both the two intraspecific treatment groups (e.g., L. fuelleborni and L. trewavasae) and the interspecific hybrids (L. fuelleborni-sired hybrids and L. trewavasae-sired hybrids), were raised to adulthood under the same aquarium conditions under which the parental generation was maintained. Additionally, since all of these F1 individuals were fed the same diet, we were able to control for possible phenotypic plasticity in trophic anatomy and morphology (e.g., van Snick Grey & Stauffer, 2004). Once they were full grown and sexually mature, these F1 fishes were later used in the experiments described below. For the morphometric and spectrophotometric analyses described below, we only used sexually mature males of each of the four treatment groups (L. fuelleborni, L. trewavasae, L. fuelleborni-sired hybrids, and L. trewavasae-sired hybrids). There is great sexual dimorphism in color pattern in these species, and given the role male color pattern plays in sexual selection in the Labeotropheus, we limited our analyses to the males (Pauers et al., 2004, 2008; Pauers & McKinnon, 2012). Additionally, the coloration of male cichlids from Lake Malaŵi tends to be more modular (i.e., consisting of several distinct biochemical, structural, or anatomical components, or modules; Klingenberg, 2009) and thus more evolutionarily labile than that of female coloration, which is considered to be integrated (i.e., comprised of interconnected, covarying components; Klingenberg, 2009; Brzozowski et al., 2014; Albertson et al., 2014), and would be more likely to show variation from the parental species than female coloration. Since we limited the investigations of coloration to sexually mature males, we similarly limited our investigations of body shape to these same males, so that we would have congruent and complimentary data for each specimen in the analyses. Many of our female L. fuelleborni had become reproductively senescent, and our attempts to obtain new L. fuelleborni stock, especially females, were hampered by a lack of L. fuelleborni from Chidunga Rocks in the U.S. aquarium trade, as well as a near cessation of imports of wild fishes from Lake Malaŵi due to shipping and supply chain issues caused by the COVID-19 pandemic. This limited our behavioral experiments to those involving L. trewavasae males and males resulting from the cross of a L. fuelleborni male and a L. trewavasae female. Geometric morphometrics Sexually mature males of each of the four treatment groups were photographed with a digital camera under fluorescent room lighting. The fishes were lightly anesthetized with MS-222 (approximately 25 mg/l), then removed from the MS-222 bath and placed on a black cloth such that the fish’s left flank was facing up towards the camera; additionally, the fish’s dorsal, anal, and pelvic fins were pinned in their erect positions. After the photographs were taken, the fish were transferred to a warm (28°C), aerated aquarium in which they were allowed to recover from the MS-222 before being returned to their stock aquaria. The photographs were imported into ImageJ, and 19 landmarks, following Pauers and McMillan (2015) and Pauers et al. (2018), were digitized from each specimen; see Fig. 1a for a picture and description of the landmarks.Fig. 1 Landmarks for the geometric morphometric analyses, and locations from which spectral data were obtained. a Morphometric landmarks; the precise locations of these points are described in Pauers et al. (2018). b Spectral data locations: A: forehead; B: dorsum; C: dorsal fin; D: caudal peduncle; E: ventrum; F: operculum The morphometric analyses followed Pauers et al. (2018). Briefly, the (x, y) coordinates of each landmark for each specimen were subjected to a Generalized Procrustes Analysis in the program Coordgen8 (Sheets 2001) to reduce the effects of size, orientation, and position in the comparison of shape. Next, a multiple regression of shape on geometric centroid size was performed using the Standard6 software which eliminates shape differences due to size. These data were then subjected to a thin-plate spline procedure to generate geometric descriptors of shape variation called relative warps (RW); this procedure was performed using the program TPSRelW (version 1.73; Rohlf, 2021). All deformation grids were generated with TPSRelW. We used Systat 10.0 (Systat Software, Inc.; Palo Alto, California, USA) to perform a MANOVA in which treatment group (e.g., L. fuelleborni, L. trewavasae, L. fuelleborni-sired hybrid offspring, and L. trewavasae-sired hybrid offspring) was used as the independent variable, and the RW scores were used as dependent variables; we then conducted Bonferroni-corrected pairwise tests among treatment groups for each RW. We also used Systat 10.0 to create bivariate plots of the RW scores. Spectrophotometry Adult males of all four treatment groups were placed individually in a weak solution of MS 222 (approximately 25 mg/l) and removed when the subject’s respiration slowed and it lost equilibrium; anesthetized fishes were then transferred to an ice bath (Pauers et al., 2004). After removal from the ice bath, fish were placed on a piece of black cloth underneath a UV-transmitting quartz lens mounted on a macro tube, which directed light via a fiber-optic cable into an Oriel Instaspec IV CCD and illuminated the fish from its dorsal surface with a Newport 100 W ozone-free xenon lamp, a 385 nm LED flashlight, and a 15 W fluorescent blacklight. We obtained reflectance data from six spots on each fish (Fig. 1b); the recorded wavelengths were converted to actual reflectance measurements by dividing them by analogous measurements taken from a Spectralon white standard. After the measurements were made, the fish were transferred to a warm (28°C), aerated aquarium in which they were allowed to recover from the MS-222 before being returned to their stock aquaria. Numerous measures of brightness, chroma, and hue were extracted from the reflectances using the pavo package (version 2.7.1) in R (Maia et al., 2019), and a principal components analysis (PCA) was performed on these chromatic variables in Systat 10.0 (Systat Software, Inc.; Palo Alto, California, USA). We then conducted an ANOVA in which treatment group was used as the independent variable and the principal components were dependent variables to determine whether the factor scores of our four treatment groups were statistically different; we additionally conducted Bonferroni-corrected pairwise tests among treatment groups for each principal component. Additionally, we were interested in the degree to which the color patterns of these treatment groups might be modular versus integrated; modular phenotypes consist of distinct, independent components; integrated phenotypes consist of interconnected, covarying components (e.g., Klingenberg, 2009). Male cichlids from Lake Malaŵi typically have coloration that is more modular, and thus more evolutionarily labile and responsive to sexual selection than the typically canalized and integrated color patterns of females (sensu Brzozowski et al., 2014; Albertson et al., 2014). We used the Principal Components Approach suggested by Brzozowski et al. (2014) and Albertson et al. (2014) to investigate the degree to which the color patterns of these fishes are integrated. We thus conducted principal components analyses separately for each treatment group using the same set of spectral characteristics as when all fishes were pooled, and examined the number of eigenvalues > 1, as well as the percent of variance explained by each principal component axis. Sexual selection We performed two experiments on sexual selection involving the two types of males available. The first of these experiments examined the aggressive reactions of male L. trewavasae to two opponents presented simultaneously, one male L. trewavasae, and one L. fuelleborni-sired hybrid male. Ten male L. trewavasae (total length: mean = 11.43 ± 0.63 cm) were the focal subjects, and ten unique pairs of opponents were created from five male L. trewavasae (total length: mean = 10.58 ± 0.47 cm) and five male L. fuelleborni-sired hybrids (total length: mean = 10.60 ± 0.28 cm). Following the methods of Pauers and Grudnowski (2020), the focal male L. trewavasae was placed in the central compartment of a three-part arena and allowed to acclimate for a period of 24–48 h; see Pauers and Grudnowski (2020) for a picture of the arena. On the day of the experiment, the two stimulus males were placed in two smaller Plexiglas aquaria that were suspended on opposite ends of the arena, and the fish were allowed to interact for ten minutes. The interactions were recorded on a digital video camera, and after the ten minute interaction period, the camera was stopped, and all individuals were removed from the arena and measured for total length and had their eggspots counted before being returned to their respective cohort tanks. We then reviewed the recording, counting the numbers of four aggressive behaviors (i.e., butts, bites, lateral displays, and frontal displays) the focal male directed to each opponent, as well as the sum of these four behaviors (“total aggression”). We specifically tested the hypothesis that the focal male L. trewavasae would direct more aggressive behaviors towards conspecific males, as found in Pauers and Grudnowski (2020). These data were checked for normality and analyzed using the appropriate (i.e., parametric versus nonparametric) statistical tests in Systat 10.0. In the second experiment, we examined female mate choice in female L. trewavasae when offered a conspecific male and a L. fuelleborni-sired hybrid male, testing the hypothesis that females should direct more responses to conspecific males. The experimental arena consisted of a filtered, heated 132 L aquarium maintained at the same parameters as the cohort aquaria. Two semi-permanent, ultraviolet-transparent Plexiglas dividers were installed 30.5 cm from each side of the aquarium; these barriers demarcated the male territories, which had a ground area of 930.25 cm2 and a volume of about 28.4 L. Each male was given a single brick (15.25 cm × 15.25 cm × 5 cm) which served as a territory and shelter; each brick was positioned such that a fish could hide behind or beside it and not be readily visible to the other fishes. Immediately in front of both clear dividers were removable opaque dividers, which allowed the fish to acclimate to the arena simultaneously without being in visual contact with one another. The centre portion of the arena, with a ground area of 1859.3 cm2 and a volume of about 56.7 l, was the female’s territory; the female was also provided a small shelter in the form of a brick (15.25 cm × 15.25 cm × 5 cm) and an artificial plant. A trio of fishes, a gravid female and two males, were randomly selected from their cohort aquaria and moved to the arena. Ten female L. trewavasae (total length: mean = 10.9 ± 0.20 cm) were the focal subjects, and ten unique pairs of opponents were created from five male L. trewavasae (total length: mean = 11.96 ± 0.66 cm; anal fin eggspots: mode = 3) and five male L. fuelleborni-sired hybrids (total length: mean = 10.94 ± 0.20 cm; anal fin eggspots: mode = 3). The female was placed into the larger, central compartment and each male was placed separately into one of the smaller male territories. The fish were allowed to acclimate to the experimental arena for a period of 48 h. After the 48-h acclimation period, the opaque dividers were removed and the interactions between the female and both stimulus males were recorded using a video camera for 20 min with no humans present. After 20 min, the recording was stopped, and all individuals were removed from the arena and measured for total length and had their eggspots counted before being returned to their respective cohort tanks. The video recordings were then reviewed, counting the number of times a female directly approached a male on the opposite side of the transparent barrier (Pauers & Grudnowski, 2022). The number of visits to a given male corresponds to the amount of time spent near that male, which is known to be indicative of male choice in the rock-dwelling cichlids of Lake Malaŵi (Couldridge & Alexander, 2001). These data were checked for normality and analyzed using the appropriate (i.e., parametric versus nonparametric) statistical tests in Systat 10.0. Results Experimental animals Our experimental crosses produced 12 L. trewavasae-sired hybrid males and seven L. fuelleborni-sired hybrid males that survived to adulthood (Fig. 2). While many of the female L. fuelleborni were responsive to the male L. trewavasae and produced at least some hybrid offspring (e.g., Pauers et al., 2018), we noticed that the female L. trewavasae were resistant to male L. fuelleborni, and only two female L. trewavasae successfully spawned with a heterospecific mate (Pauers, pers. obsv.). We then selected 12 adult male L. fuelleborni and 12 adult male L. trewavasae from our cohort stocks for the morphometric and spectrophotometric analyses.Fig. 2 Representative males of each treatment group. a Labeotropheus fuelleborni; b L. trewavasae; c L. fuelleborni-sired hybrid; d L. trewavasae-sired hybrid Geometric morphometrics The relative warps analysis found significant differences in morphology among the four treatment groups of Labeotropheus. Relative Warp 1 explains 25.07% of the variation in body shape and differentiates a deeper body and upturned neurocranium and snout, as seen in L. fuelleborni and the L. fuelleborni-sired hybrids, from a slender body with a straighter head and horizontal snout as seen in L. trewavasae and the L. trewavasae-sired hybrids. Relative Warp 2 explains 14.58% of the variation in shape among our specimens, and differentiates the prominently upturned neurocranium and snout of the L. fuelleborni-sired hybrids from the head profiles found in the other three treatment groups (Fig. 3).Fig. 3 a Relative warp plot for the geometric morphometric data. Relative Warp 1 accounts for 25.07% of the variation in body shape among the four treatment groups, and distinguishes the deeper-bodied L. fuelleborni and L. fuelleborni-sired hybrids from the slender L. trewavasae and L. trewavasae-sired hybrids. Relative Warp 2 accounts for 14.58% of the variation, and distinguishes the more drastically upturned neurocranium of the L. fuelleborni-sired hybrids from the other three treatment groups. The ellipses are 95% confidence ellipses around the group centroid. b Deformation grid for both L. trewavasae and L. trewavasae-sired hybrids. c Deformation grid for L. fuelleborni. d Deformation grid for L. fuelleborni-sired hybrids. All deformation grids exaggerated 5X In Fig. 3, it is interesting to note that L. trewavasae-sired hybrids have a body shape that is similar to that of L. trewavasae. Along both Relative Warps 1 and 2, these hybrids are significantly different from L. fuelleborni, though not from L. trewavasae (Table 1; Supplementary Table 1). The L. fuelleborni-sired hybrids, on the other hand, are significantly different from all of the other treatment groups of Labeotropheus along Relative Warp 1, but are only significantly different from the L. trewavasae-sired hybrids along Relative Warp 2 (Table 1; Supplementary Table 1).Table 1 MANOVA on relative warps 1–5; Wilks’ λ = 0.40; F15, 83 = 12.196; P ≤ 0.001 Variable Sum of squares df Mean square F P RW 1 0.007 3 0.002 20.829 ≤ 0.001 Error 0.004 34 0.000 RW 2 0.002 3 0.001 4.718 ≤ 0.01 Error 0.004 34 0.000 RW 3 0.002 3 0.001 7.131 ≤ 0.001 Error 0.004 34 0.000 RW 4 0.001 3 0.000 5.908 ≤ 0.01 Error 0.004 34 0.000 RW 5 0.000 3 0.000 0.039 0.989 Error 0.004 34 0.000 Relative Warps 6–34 were ns; data not shown. Results of pairwise comparisons of treatment groups can be found in Supplementary Table 1 Spectrophotometry The average reflectances of each treatment group of Labeotropheus for each of the six patches measured are shown in Fig. 4. These reflectance curves illustrate the chromatic differences among the treatment groups, especially the L. fuelleborni-sired hybrids. These hybrids have strong ultraviolet reflectance in their caudal peduncle, operculum, and ventrum, with a peak at about 350 nm, but lack the additional peak at 400 nm found in the other three treatment groups (Fig. 4). Interestingly, a somewhat inverse pattern is found in the dorsum and forehead reflectances, where the L. fuelleborni-sired hybrids lack a strong ultraviolet component to their coloration, especially in comparison to L. trewavasae, but have a strong peak at about 425 nm (Fig. 4). The reflectance of the dorsal fin distinguishes L. trewavasae from the other three treatment groups, with its unique broad peak throughout the ultraviolet and violet wavelengths, but lack of a subsequent and relatively less intense peak in the longer wavelengths as found in L. fuelleborni and both hybrids (Fig. 4).Fig. 4 Reflectances obtained at the six body locations for all four treatment groups. The titles of each plot are the body region from which the reflectances were measured. Each curve is the average of all the members of a given treatment group; error bars are omitted for clarity. Yellow: L. fuelleborni (n = 12); blue: L. trewavasae (n = 12); green: L. trewavasae-sired hybrids (n = 12); red: L. fuelleborni-sired hybrids (n = 7) The principal components analysis performed on all of the various measures of brightness, chroma, and hue reveals further distinctions among the four treatment groups. The loadings for the first two principal components are shown in Table 2. The first axis, Color PC 1, accounts for 19.35% of the variation in color, and discriminates between the high and narrow-peaked ultraviolet reflectance of the caudal peduncle and ventrum found on the L. fuelleborni-sired hybrids, as well as the more bimodal, ultraviolet and violet caudal peduncle and ventrum of the other three treatment groups (Fig. 5). The second principal component, Color PC 2, accounts for 16.97% of the variation in color, and distinguishes the unusual dorsum and operculum reflectances of the L. fuelleborni-sired hybrids from the other treatment groups (Fig. 5).Table 2 Principal component loadings from spectral variables; note that all variables were entered in the same analysis, but are separated here by body region for clarity and simplicity Variable Caudal Peduncle Dorsum Dorsal Fin PC 1 PC 2 PC 1 PC 2 PC 1 PC 2 Total brightness 0.642 0.463 0.411 0.667 0.523 0.059 Mean brightness 0.642 0.463 0.411 0.667 0.523 0.059 Intensity 0.138 0.656 0.439 0.651 0.467 − 0.004 Ultraviolet chroma − 0.491 0.404 0.324 − 0.723 0.102 − 0.064 Violet chroma − 0.441 0.385 0.372 − 0.670 0.192 − 0.009 Blue chroma 0.677 − 0.245 0.162 0.674 0.286 0.406 Green chroma 0.374 − 0.369 − 0.346 0.569 − 0.260 − 0.110 Yellow chroma 0.289 − 0.398 − 0.484 0.298 − 0.304 − 0.226 Red chroma 0.161 − 0.407 − 0.387 − 0.272 − 0.279 − 0.314 Spectral saturation − 0.418 0.397 0.317 − 0.154 − 0.057 − 0.322 Contrast − 0.043 0.622 0.473 0.576 0.221 − 0.091 Peak λ 0.004 0.016 − 0.107 0.672 − 0.223 0.166 λ of maximum negative slope 0.285 − 0.193 − 0.361 0.163 − 0.364 0.215 λ of median reflectance 0.193 − 0.059 0.375 − 0.189 0.066 − 0.064 Forehead Opercular Tab Ventrum PC 1 PC 2 PC 1 PC 2 PC 1 PC 2 Total brightness 0.266 0.724 0.522 0.603 0.743 0.312 Mean brightness 0.266 0.724 0.522 0.603 0.743 0.312 Intensity 0.353 0.678 0.703 0.376 0.630 0.447 Ultraviolet chroma 0.544 − 0.579 0.452 − 0.646 − 0.609 0.000 Violet chroma 0.631 − 0.498 0.517 − 0.615 − 0.504 − 0.149 Blue chroma 0.320 0.537 0.093 0.388 0.686 − 0.336 Green chroma − 0.552 0.516 − 0.489 0.594 0.461 0.287 Yellow chroma − 0.806 0.300 − 0.495 0.541 0.425 0.289 Red chroma − 0.800 − 0.129 − 0.564 0.393 0.096 0.230 Spectral saturation 0.444 − 0.309 0.402 − 0.560 − 0.600 0.036 Contrast 0.511 0.519 0.764 0.166 0.379 0.367 Peak λ − 0.423 0.332 − 0.017 0.179 0.319 0.054 λ of maximum negative slope − 0.113 − 0.020 − 0.540 0.410 − 0.270 − 0.024 λ of median reflectance − 0.403 − 0.192 − 0.433 0.186 0.038 − 0.052 Fig. 5 Plot of color principal component 1 (Color PC 1) versus color principal component 2 (Color PC 2); ellipses are 95% confidence around the group centroid. Color PC 1 explains 19.35% of the variation in coloration among the treatment groups, and largely encompasses the strong ultraviolet components of the caudal peduncle and ventrum; see Table 2 for factor loadings. Color PC 2 accounts for 16.97% of the variation, and differentiates a very reflective dorsum, as found in L. trewavasae and the L. fuelleborni-sired hybrids at the positive end, versus an operculum that reflects strongly in the violet wavelengths, as found in L. fuelleborni, L. trewavasae, and L. trewavasae-sired hybrids, at the negative end (c.f. Table 2) An ANOVA of the scores of Color PCs 1 and 2 for each treatment group indicates significant differences among the treatment groups for both (Table 3). The L. fuelleborni-sired hybrids are significantly different from the other three groups along both Color PC 1 and 2 (Table 3). The L. trewavasae-sired hybrids are significantly different from L. trewavasae along both, but not from L. fuelleborni (Table 3).Table 3 Analysis of variance for color principal components (A) Color PC 1 (n = 38; multiple R2 = 0.584) Variable Sum of squares df Mean square F P Treatment Group 21.619 3 7.206 15.929 ≤ 0.001 Error 15.381 34 0.452 Pairwise comparisons L. fuelleborni Hybrid 1 (Lt Sire) Hybrid 2 (Lf Sire) Hybrid 1 (Lt Sire) − 0.288ns Hybrid 2 (Lf Sire) 1.080* − 1.368* L. trewavasae 1.183 0.895* 2.263* (B) Color PC 2 (n = 38; multiple R2 = 0.653) Variable Sum of squares df Mean square F P Treatment Group 24.144 3 8.048 21.285 ≤ 0.001 Error 12.856 34 0.378 Pairwise comparisons L. fuelleborni Hybrid 1 (Lt Sire) Hybrid 2 (Lf Sire) Hybrid 1 (Lt Sire) 0.297ns Hybrid 2 (Lf Sire) − 1.883* 2.180*** L. trewavasae 0.856* 1.153* − 1.027 ns not significant P = 0.05; P = 0.01; **P = 0.001 Exploring modularity and integration in the pigmentation of the four treatment groups using the approach of Brzozowski et al. (2014) and Albertson et al. (2014) revealed that, unlike the other three treatment groups, the pigmentation of the L. fuelleborni-sired hybrid males is consistent with an integrated color pattern. For both parental species, nine eigenvalues were > 1, with the first axis accounting for 29.81% of the variation in L. fuelleborni, and 30.20% in L. trewavasae. The L. trewavasae-sired hybrids had 10 eigenvalues > 1, and the first principal component axis explained 29.73% of the observed variation. Finally, the L. fuelleborni-sired hybrids had six eigenvalues > 1, and the first axis accounted for 36.88% of the variation in the color of these fishes. The relatively lower number of eigenvalues with values > 1, and the greater percentage of variation explained by the first principal component, are both indicative of integration (Table 4).Table 4 Number of eigenvalues and percentage of variance explained by each principal component for the principal component analyses performed on the spectral data for each treatment group Treatment group Number of eigenvalues > 1 Percent variance explained by each axis 1 2 3 4 5 6 7 8 9 10 L. fuelleborni 9 29.81 16.12 13.90 11.30 8.78 6.84 5.44 4.19 3.62 – L. trewavasae 9 30.20 17.86 14.31 11.74 8.62 6.71 4.37 3.93 2.26 – L. fuelleborni-sired hybrids 6 36.88 18.51 17.40 12.74 9.83 4.64 – – – – L. trewavasae-sired hybrids 10 29.73 18.25 12.44 10.29 9.72 5.79 5.13 4.00 3.18 1.46 Male–male aggression All 10 focal male L. trewavasae responded to the stimulus males, yielding usable data for these analyses. The data were not normally distributed, so Wilcoxon signed rank tests were used to test for pairwise differences in the aggression directed to the two different opponents. The focal males did not discriminate between L. trewavasae and L. fuelleborni-sired hybrid opponents, directing approximately equal numbers of aggressive behaviors to either opponent. None of the differences were significant, neither the total sum of all aggressive behaviors (total aggression: Z = − 1.020, P = 0.308; Fig. 6a), nor the number of individual aggressive behaviors (lateral displays: Z = − 0.803, P = 0.407; frontal displays: Z = − 1.219, P = 0.223; bites: Z = − 0.840, P = 0.401; butts: Z = − 0.867, P = 0.386).Fig. 6 Responses of male and female L. trewavasae to conspecific and L. fuelleborni-sired males. a Male L. trewavasae directed slightly more aggressive acts to conspecific opponents, but this difference is not statistically significant. b Female L. trewavasae were much more responsive to male L. trewavasae than they were to male L. fuelleborni-sired hybrids Female mate choice Of the 10 attempted trials, nine yielded usable data; in one case, a male was able to get around the permanent transparent divider and was found in direct contact with the female during the acclimation period. In the nine trials that provided usable data, the data were normally distributed, so parametric analyses were used to analyze the data. With respect to the males, despite the difference in mean length between L. trewavasae and L. fuelleborni-sired hybrid males noted above, the difference in length between a pair of males did not influence the number of responses directed to either opponent (R2 = 0.124; F1,7 = 0.989; P = 0.353). While the L. fuelleborni-sired hybrid males tended to perform more displays than L. trewavasae males (hybrids: 9.0 ± 3.7 displays; L. trewavasae: 3.6 ± 1.1 displays), this difference was not significant (t8 = 1.623, P = 0.143). The great difference in the average number of displays performed was due to a single hybrid male who performed 34 displays, and, when this individual is excluded from the dataset, the average number of displays performed by L. fuelleborni-sired hybrid males falls to 5.8 ± 1.9. Finally, the number of displays performed by one male was not related to the number of displays performed by his opponent (R2 = 0.179; F1,7 = 1.521; P = 0.257). Female receptive behavior towards the two different males was consistent. Female L. trewavasae directed significantly more receptive responses to L. trewavasae males than they did to L. fuelleborni-sired hybrid males (t8 = − 6.415, P ≤ 0.001; Fig. 6b). Discussion Male hybrids of Labeotropheus fuelleborni and L. trewavasae from the Chidunga Rocks in southwestern Lake Malaŵi produced from reciprocal crosses differ in body shape and coloration. The hybrids resulting from a cross of a male L. trewavasae and a female L. fuelleborni have a body shape intermediate to the parental species, and a coloration most similar to that of the males of the maternal species; this agrees with the findings of Pauers et al. (2018). Conversely, the hybrids that are produced with a male L. fuelleborni and a female L. trewavasae present a combination of morphological and color features that are unique and different to that of either parental species, as well as that of the reciprocal hybrid. As such, while the L. trewavasae-sired hybrids are phenotypically intermediate to their parental species, the L. fuelleborni-sired hybrids have a novel combination of morphometry and pigmentation, and are consistent with what would be expected in a transgressive hybrid. Pauers et al. (2018) found that the body shape of F1 hybrids created by crossing female L. fuelleborni and male L. trewavasae contributed to a reduced foraging efficiency. In this study, hybrids produced by L. trewavasae sires and L. fuelleborni dams had an upturned and expanded neurocranium not found in either of the parental species that contributed a slower growth rate in laboratory conditions (Pauers et al., 2018). Given how consequential body shape is for foraging and maneuvering in the aquatic environment (Higham et al., 2015), especially for the algae-grazing cichlids of Lake Malaŵi (Stauffer & Posner, 2006; Rupp and Hulsey, 2014), the inability for these hybrids to thrive under these conditions is not surprising. It would thus be especially enlightening to see how the L. fuelleborni-sired hybrids fare in a similar experiment. Brzozowski et al. (2014) and Albertson et al. (2014), using their innovative approach to the analysis of color patterns of the cichlids of Lake Malaŵi, found that males have less integrated, more modular color patterns. Such color patterns, consisting of separate, distinct units of pigmentation, would allow them to evolve rapidly, especially in response to sexually selection (Brzozowski et al., 2014; Albertson et al., 2014). In their analyses, they used the number of eigenvalues > 1, as well as the amount of variance explained by each principal component, to determine the degree to which color patterns were modular; a large number of eigenvalues > 1 and a lower amount of variance explained by each principal component indicated a greater degree of modularity, versus integration, in a color pattern. Our results of the principal components analysis of the spectral data are consistent with this pattern. Male L. fuelleborni, L. trewavasae, and L. trewavasae-sired hybrids, while differing somewhat in their spectral characteristics, nonetheless have modular color patterns, as demonstrated by the relatively large number of eigenvalues > 1, and the lower amount of variance explained by each principal component axis. Conversely, the L. fuelleborni-sired hybrid males had a spectrally unique color pattern, one that was rich in ultraviolet wavelengths, but lacking violet and blue wavelengths, at several of the body regions we sampled. Additionally, for this treatment group, there were fewer eigenvalues > 1, and a greater percentage of variance was explained by each principal component. It is not surprising, then, that these transgressive hybrid males would not be recognized by female L. trewavasae as a potential mate. Female rock-dwelling cichlids of Lake Malaŵi, and especially the Labeotropheus, have long been known to select their mates visually, especially on the basis of male nuptial color (Jordan et al., 2003; Knight & Turner, 2004; Pauers et al., 2004; Pauers & Grudnowski, 2022). The body shape of these L. fuelleborni-sired hybrids, and especially their unusual coloration, makes them visually distinct from L. trewavasae males, at least to a human observer, although the spectral distribution of their color pattern also suggests that these differences should be visible to female L. trewavasae (Carleton & Kocher, 2001; Pauers et al., 2004). The results of the male-male aggression experiments are less clearly interpreted. Male rock-dwelling cichlids from Lake Malaŵi use the color patterns of their opponents to ascertain the greatest threat to their ability to attract a mate (i.e., males colored most similarly to themselves) and modulate their aggression accordingly (Pauers et al., 2008; Pauers & McKinnon, 2012; Pauers & Grudnowski, 2020). Given the differences in coloration between L. trewavasae and L. fuelleborni-sired males, it is reasonable to expect that focal male L. trewavasae would direct more aggressive behaviors to L. trewavasae opponents, but this was not the case. The focal male L. trewavasae in these experiments directed equal numbers of aggressive behaviors to both opponents. It could be possible that the spectral characteristics of the color pattern of L. fuelleborni-sired hybrids are just similar enough to those of L. trewavasae that they do not meet some inherent threshold of species recognition (Crapon de Caprona, 1986; Ribbink, 1991), assuming that males identify their opponents using visual cues (Pauers et al., 2008, Pauers & McKinnon, 2012). The results from this experiment suggest that, in a natural and unaltered habitat, the L. fuelleborni-sired hybrid males would be treated as a conspecific by males of both parental species, and would thus have no advantage over male L. trewavasae during intrasexual aggressive encounters. To the best of our knowledge, this is the first time that the performance of male hybrids of Lake Malawi cichlids in intrasexual aggressive encounters has been tested. Taken together, the results of our behavioral experiments strongly suggest that these transgressive L. fuelleborni-sired hybrids are not likely to be successful competitors or mates in a natural population in an undisturbed habitat (but see Seehausen et al., 1997). Young rock-dwelling cichlids in Lake Malaŵi typically do not migrate more than a few meters from where they are released, and are thus most likely to join the community frequented by their mothers (Ribbink et al., 1983; Ribbink, 1991). Since the L. fuelleborni-sired hybrid males used in our experiments were carried by female L. trewavasae, in Lake Malaŵi they would come to sexual maturity surrounded by L. trewavasae; our results suggest that these hybrids would struggle in sexually selected interactions with adults of their parental species. Given the lack of L. fuelleborni females and L. trewavasae-sired hybrid males in our experiments, results of our behavioral studies provide an incomplete picture of the way hybrid males might interact in a natural hybrid zone of Labeotropheus. Nonetheless, these results, coupled with the morphological and spectrophotometric data, allow us to propose further investigations to determine whether or not these findings are broadly applicable. An obvious place to start would be to perform reciprocal experiments in which female L. fuelleborni are offered a choice between L. trewavasae-sired hybrid males and male L. fuelleborni. Since the L. trewavasae-sired hybrid males are very similar in appearance to L. fuelleborni, both morphologically and chromatically, it might be possible that these hybrids would receive attention from female L. fuelleborni. With regards to male-male aggression, the similarity, at least to a human observer, between L. trewavasae-sired and L. fuelleborni males suggests that focal male L. fuelleborni should direct equal amounts of aggression towards conspecific and L. trewavasae-sired opponents. Finally, it would be extremely informative to examine the mate choice preferences of both L. fuelleborni- and L. trewavasae-sired females. If these females prefer non-hybrid, parental males, that could explain the presence and persistence of gene flow among the cichlids of Lake Malaŵi (Mims et al., 2010; Selz et al., 2014a, b; Hulsey et al., 2017). On the other hand, if hybrid females prefer hybrid males, this could lend credence to the hypothesis that hybridization is an important source of phenotypically divergent species in Lake Malaŵi (Feller et al., 2020). Although morphological and behavioral evidence from the wild is exceedingly rare, molecular genetics reveals that hybridization has undoubtedly occurred during the evolution of the species flock of cichlids endemic to Lake Malaŵi (e.g., Mims et al., 2010; Loh et al., 2013; Meier et al., 2017; Malinsky et al., 2018; Svardal et al., 2020). Our results indicate that hybridization does indeed generate phenotypic novelty in the Labeotropheus, but that the emergence of novelty depends upon the parentage of the hybrids, since one direction produces intermediate hybrids, and the other produces novel combinations of traits. Perhaps most importantly, our experiments suggest that one reason for the rarity of hybrids in modern day Lake Malaŵi could be the fact that transgressive males were neither preferred by females of their maternal species, nor did they receive less aggression from males of the maternal species. In the vast majority of studies involving hybridization in cichlids from Lake Malaŵi, experimental crosses were made in only a single direction (e.g., McElroy & Kornfield, 1993; Albertson & Kocher, 2001; Brzozowski et al., 2014; Pauers et al., 2018). In the relatively few studies in which reciprocal crosses were made, the resulting hybrid progeny were pooled in the subsequent analyses, thus obscuring their parentage (e.g., Husemann et al., 2017). Given the results presented in this paper, as well as the roles sexual conflict and chromosomal sex determination play in determining the chromatic phenotype of male cichlids from Lake Malaŵi (Roberts et al., 2009), it is important for future studies to compare hybrid offspring from reciprocal crosses. Supplementary Information Below is the link to the electronic supplementary material.Supplementary file1 (DOC 24 kb) Funding This project was supported by the Orth Family Ichthyology Research Fund of the Milwaukee Public Museum, the American Cichlid Association Guy D. Jordan Research Fund, and by donations of aquarium equipment by Aqueon, Inc. (Franklin, Wisconsin, USA). LJA’s participation in these studies was made possible by a UW-Milwaukee Supporting Undergraduate Research Fellowship. The experiments summarized in this paper adhered to the ASAB/ABS Guidelines for the Use of Animals in Research, the legal requirements of the United States of America and the guidelines of the University of Wisconsin-Milwaukee Institutional Animal Care and Use Committee. This research project was reviewed and approved by the UWM IACUC and assigned animal care and use Protocol number 18-19#10. Data availability The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. Declarations Competing Interests None of the authors have any competing interests to report. Guest editors: S. Koblmüller, R. C. Albertson, M. J. Genner, K. M. Sefc & T. Takahashi / Advances in Cichlid Research V: Behavior, Ecology and Evolutionary Biology Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Albertson RC Kocher TD Assessing morphological differences in an adaptive trait: a landmark-based morphometric approach Journal of Experimental Zoology 2001 289 385 403 10.1002/jez.1020 11351326 Albertson RC Powder KE Hu Y Coyle KP Roberts RB Parsons KJ Genetic basis of continuous variation in the levels and modular inheritance of pigmentation in cichlid fishes Molecular Ecology 2014 23 5135 5150 10.1111/mec.12900 25156298 Barlow GW The puzzling paucity of feeding territories among freshwater fishes Marine Behaviour and Physiology 1993 23 155 174 10.1080/10236249309378863 Barlow GW The Cichlid Fishes: Nature’s Grand Experiment in Evolution 2000 Cambridge Perseus Publishing Barlow GW How behavioural studies contribute to the species problem: a piscine perspective Fish and Fisheries 2002 3 197 202 10.1046/j.1467-2979.2002.00083.x Brzozowski F Roscoe J Parsons K Albertson RC Sexually dimorphic levels of color trait integration and the resolution of sexual conflict in Lake Malawi cichlids Journal of Experimental Zoology Part B: Molecular and Developmental Evolution 2014 318 268 278 10.1002/jez.b.22443 Carleton KL Kocher TD Cone opsin genes of African cichlid fishes: tuning spectral sensitivity by differential gene expression Molecular Biology and Evolution 2001 18 1540 1550 10.1093/oxfordjournals.molbev.a003940 11470845 Concannon MR Albertson RC The genetic and developmental basis of an exaggerated craniofacial trait in East African cichlids Journal of Experimental Zoology B: Molecular Development and Evolution 2015 324 662 670 10.1002/jez.b.22641 Couldridge VCK Alexander GJ Does the time spent near a male predict female mate choice in a Malawian cichlid? Journal of Fish Biology 2001 59 667 672 10.1111/j.1095-8649.2001.tb02370.x Coyne JA Orr HA Speciation 2004 Sunderland Sinauer Associates Crapon de Caprona M-D The use of fertile hybrids for the study of the accuracy of species recognition in cichlids Annals of the Royal Museum for Central Africa 1986 251 117 120 Danley PD Husemann M Ding B Dipietro LM Beverly EJ Peppe DJ The impact of the geologic history and paleoclimate on the diversification of East African cichlids International Journal of Evolutionary Biology 2012 2012 574851 10.1155/2012/574851 22888465 Egger B Sefc KM Makasa L Sturmbauer C Sturmbauer W Introgressive hybridization between color morphs in a population cichlid fishes twelve years after human-induced secondary admixis Journal of Heredity 2012 103 515 522 10.1093/jhered/ess013 22563125 Feller AF Selz OM McGee MD Meier JI Mwaiko S Seehausen O Rapid generation of ecologically relevant behavioral novelty in experimental cichlid hybrids Ecology and Evolution 2020 2020 7445 7462 10.1002/ece3.6471 Gante HF Matschiner M Malstrom M Jakobsen KS Jentoft S Salzburger W Genomics of speciation and introgression in Princess cichlid fishes from Lake Tanganyika Molecular Ecology 2016 25 6143 6161 10.1111/mec.13767 27452499 Genner MJ Turner GF Ancient hybridization and phenotypic novelty within Lake Malawi’s cichlid fish radiation Molecular Biology and Evolution 2012 29 195 206 10.1093/molbev/msr183 22114359 Genner MJ Turner GF Timing of population expansions within the Lake Malawi haplochromine cichlid fish radiation Hydrobiologia 2015 748 121 132 10.1007/s10750-014-1884-7 Haesler MP Seehausen O Inheritance of female mating preference in a sympatric sibling species pair of Lake Victoria cichlids: implications for speciation Proceedings of the Royal Society of London Series B 2005 272 237 245 15705547 Hedrick PW Adaptive introgression in animals: examples and comparison to new mutation and standing variation as sources of adaptive variation Molecular Ecology 2013 22 4606 4618 10.1111/mec.12415 23906376 Higham TE Stewart WJ Wainwright PC Turbulence, temperature, and turbidity: the ecomechanics of predator-prey interactions in fishes Integrative and Comparative Biology 2015 55 6 20 10.1093/icb/icv052 25980563 Holzman R Hulsey CD Mechanical transgressive segregation and the rapid origin of trophic novelty Scientific Reports 2017 7 40306 10.1038/srep40306 28079133 Husemann M Tobler M McCauley C Ding B Danley PD Body shape differences in a pair of closely related Malawi cichlids and their hybrids: effects of genetic variation, phenotypic plasticity, and transgressive segregation Ecology and Evolution 2017 7 4336 4346 10.1002/ece3.2823 28649345 Hulsey, C.D., J. Zheng, B.C. Faircloth, A. Meyer & M.E. Alfaro, 2017. Phylogenomic analysis of Lake Malawi cichlid fishes: Further evidence that the three-stage model of diversification does not fit. Molecular Phylogenetics and Evolution 114: 40–48. Ivory SJ Blome MW King JW McGlue MM Cole JE Cohen AS Environmental change explains cichlid adaptive radiation at Lake Malawi over the past 1.2 million years Proceedings of the National Academy of Sciences USA 2016 113 11895 11900 10.1073/pnas.1611028113 Jordan R Kellogg K Juanes F Stauffer JR Jr Evaluation of female mate choice cues in a group of Lake Malawi Mbuna (Cichlidae) Copeia 2003 2003 181 186 10.1643/0045-8511(2003)003[0181:EOFMCC]2.0.CO;2 Klingenberg CP Morphometric integration and modularity in configurations of landmarks: tools for evaluating a priori hypotheses Evolution and Development 2009 11 405 421 10.1111/j.1525-142X.2009.00347.x 19601974 Knight ME Turner GF Laboratory mating trials indicate incipient speciation by sexual selection among populations of the cichlid fish Pseudotropheus zebra from Lake Malawi Proceedings of the Royal Society B 2004 271 675 680 10.1098/rspb.2003.2639 15209099 Koblmüller S Nevado B Makasa L Van Steenberge M Vanhove MPM Verheyen E SturmbauerSefc CKM Phylogeny and phylogeography of Altolamprologus: ancient introgression and recent divergence in a rock-dwelling Lake Tanganyika cichlid genus Hydrobiologia 2017 791 35 50 10.1007/s10750-016-2896-2 Kornfield IL Smith PF African cichlid fishes: model systems for evolutionary biology Annual Review of Ecology and Systematics 2000 31 163 196 10.1146/annurev.ecolsys.31.1.163 Loh Y-HE Bezault E Muenzel FM Roberts RB Swofford R Barluenga M Kidd CE Howe AE Di Palma F Lindblad-Toh K Hey J Seehausen O Salzburger W Kocher TD Streelman JT Origins of shared genetic variation in African cichlids Molecular Biology and Evolution 2013 30 906 917 10.1093/molbev/mss326 23275489 Maia R Gruson H Endler JA White TE pavo 2: new tools for the spectral and spatial analysis of colour in R Methods in Ecology and Evolution 2019 2019 1097 1107 10.1111/2041-210X.13174 Malinsky M Svardal H Tyers AM Miska EA Genner MJ Turner GF Durbin R Whole-genome sequences of Malawi cichlids reveal multiple radiations interconnected by gene flow Nature Ecology and Evolution 2018 2 1940 1955 10.1038/s41559-018-0717-x 30455444 Mayr E Animal Species and Evolution 1963 Cambridge Belknap Press McElroy DM Kornfield I Novel jaw morphology in hybrids between Pseudotropheus zebra and Labeotropheus fuelleborni (Teleostei: Cichlidae) from Lake Malawi, Africa Copeia 1993 1993 933 945 10.2307/1447071 Meier JI Marques DA Mwaiko S Wagner CE Excoffier L Seehausen O Ancient hybridization fuels rapid cichlid fish adaptive radiations Nature Communications 2017 8 14363 10.1038/ncomms14363 28186104 Meyer BS Matschiner M Salzburger W Disentangling incomplete lineage sorting and introgression to refine species-tree estimates for Lake Tanganyika cichlid fishes Systematic Biology 2017 66 531 550 27539485 Mims MC Hulsey CD Fitzpatrick BM Streelman JT Geography disentangles introgression from ancestral polymorphism in Lake Malawi cichlids Molecular Ecology 2010 19 940 951 10.1111/j.1365-294X.2010.04529.x 20149093 Pauers MJ Grudnowski JA Assortative aggression among males in a sympatric pair of Labeotropheus from Lake Malaŵi, Africa Journal of Fish Biology 2020 2020 1 7 Pauers MJ Grudnowski JA Female preferences for conspecific males indicate reproductive isolation between sympatric Labeotropheus Ahl from Lake Malaŵi Ethology 2022 128 482 488 10.1111/eth.13282 Pauers MJ McKinnon JS Sexual selection on color and behavior within and between cichlid populations: implications for speciation Current Zoology 2012 58 475 483 10.1093/czoolo/58.3.475 Pauers MJ McMillan SA Geometric morphometrics reveals surprising diversity in the Lake Malawi cichlid genus Labeotropheus Hydrobiologia 2015 748 145 160 10.1007/s10750-014-1941-2 Pauers MJ McKinnon JS Ehlinger TJ Directional sexual selection on chroma and within-pattern colour contrast in Labeotropheus fuelleborni Proceedings of the Royal Society of London Series B 2004 271 S444 S447 10.1098/rsbl.2004.0215 15801599 Pauers MJ Kapfer JM Fendos CE Berg CS Aggressive biases towards similarly coloured males in Lake Malawi cichlid fishes Biology Letters 2008 4 156 159 10.1098/rsbl.2007.0581 18230585 Pauers MJ Ehlinger TJ McKinnon JS Female and male visually based mate preferences are consistent with reproductive isolation between populations of the Lake Malawi endemic Labeotropheus fuelleborni Current Zoology 2010 56 65 72 10.1093/czoolo/56.1.65 Pauers MJ Fox KR Hall RA Patel K Selection, hybridization, and the evolution of morphology in the Lake Malaŵi endemic cichlids of the genus Labeotropheus Scientific Reports 2018 2018 15842 10.1038/s41598-018-34135-x Ribbink AJ Alternative life-history styles of some African cichlid fishes Environmental Biology of Fishes 1990 28 87 100 10.1007/BF00751029 Ribbink AJ Keenleyside MHA Distribution and ecology of the cichlids of the African Great Lakes Cichlid Fishes: Behaviour, Ecology and Evolution 1991 London Chapman & Hall 36 59 Ribbink AJ Marsh BA Marsh AC Ribbink AC Sharp BJ A preliminary survey of the cichlid fishes of rocky habitats in Lake Malawi South African Journal of Zoology 1983 18 149 310 10.1080/02541858.1983.11447831 Roberts RB Ser JR Kocher TD Sexual conflict resolved by invasion of a novel sex determiner in Lake Malawi cichlid fishes Science 2009 326 998 1001 10.1126/science.1174705 19797625 Rohlf, F.J, 2021. tpsRelw: Relative warps analysis, version 1.75. https://www.sbmorphometrics.org/morphmet/tpsRelww64.exe. Rometsch SJ Torres-Dowdall J Machado-Schiaffino G Karagic N Meyer A Dual function and associated costs of a highly exaggerated trait in a cichlid fish Ecology and Evolution 2021 11 17496 17508 10.1002/ece3.8383 34938524 Rupp MF Hulsey CD Influence of substrate orientation on feeding kinematics and performance of algae grazing Lake Malawi cichlid fishes Journal of Experimental Biology 2014 217 3057 3066 24948641 Santos-Santos, J.H., L. Audenaert, E. Verheyen & D. Adriaens, 2021. Ontogenetic divergence generates novel phenotypes in hybrid cichlids. Anatomy 238: 1116–1127 Seehausen O van Alphen JJM Witte F Cichlid fish diversity threatened by eutrophication that curbs sexual selection Science 1997 277 1808 1811 10.1126/science.277.5333.1808 Selz OM Seehausen O Interspecific hybridization can generate functional novelty in cichlid fish Proceedings of the Royal Society of London Series B 2019 286 20191621 31640510 Selz OM Thommen R Mann ME Seehausen O Behavioural isolation may facilitate homoploid hybrid speciation in cichlid fish Journal of Evolutionary Biology 2014 27 275 289 10.1111/jeb.12287 24372872 Selz OM Lucek K Young KA Seehausen O Relaxed trait covariance in interspecific cichlid hybrids predicts morphological diversity in adaptive radiations Journal of Evolutionary Biology 2014 27 11 24 10.1111/jeb.12283 24330234 Smith PF Konings A Kornfield I Hybrid origin of a cichlid population in Lake Malawi: implications for genetic variation and species diversity Molecular Ecology 2003 12 2497 2504 10.1046/j.1365-294X.2003.01905.x 12919487 Stauffer JR Jr Posner I An investigation of the utility of feeding angles among Lake Malawi rock-dwelling cichlids (Teleostei: Cichlidae) Copeia 2006 2006 289 292 10.1643/0045-8511(2006)6[289:AIOTUO]2.0.CO;2 Stauffer JR Jr Bowers NJ Kocher TD McKaye KR Evidence of hybridization between Cynotilapia afra and Pseudotropheus zebra (Teleostei: Cichlidae) following an intralacustrine translocation in Lake Malawi Copeia 1996 1996 203 208 10.2307/1446959 Stelkens RB Schmid C Selz O Seehausen O Phenotypic novelty in experimental hybrids is predicted by the genetic distance between species of cichlid fish BMC Evolutionary Biology 2009 9 283 10.1186/1471-2148-9-283 19961584 Svardal H Quah FX Malinsky M Ngatunga BP Miska EA Salzburger W Genner MJ Turner GF Durbin R Ancestral hybridization facilitated species diversification in the Lake Malawi cichlid fish adaptive radiation Molecular Biology and Evolution 2020 37 1100 1113 10.1093/molbev/msz294 31821500 Svensson O Egger B Gricar B Woodhouse K van Oosterhout C Salzburger W Seehausen O Turner GF Segregation of species-specific male attractiveness in F2 hybrid Lake Malawi cichlid fish International Journal of Evolutionary Biology 2011 2011 1 7 10.4061/2011/426179 Svensson O Woodhouse K van Oosterhout C Smith A Turner GF Seehausen O The genetics of mate preferences in hybrids between two young and sympatric Lake Victoria cichlid species Proceedings of the Royal Society of London Series B 2017 284 20162332 28202807 van Snick Grey E Stauffer JR Jr Phenotypic plasticity: its role in trophic radiation and explosive speciation in cichlids (Teleostei: Cichlidae) Animal Biology 2004 54 137 158 10.1163/1570756041445191
PMC009xxxxxx/PMC9731645.txt	==== Front Sustain Futur Sustain Futur Sustainable Futures (Amsterdam, Netherlands) 2666-1888 The Author(s). Published by Elsevier Ltd. S2666-1888(22)00036-3 10.1016/j.sftr.2022.100102 100102 Article COVID-19 disruptions and Norwegian food and pharmaceutical supply chains: Insights into supply chain risk management, resilience, and reliability Bø Eirill a⁎ Hovi Inger Beate b Pinchasik Daniel Ruben b a Department of Accounting and Operations Management, BI Norwegian Business School, Nydalsveien 37, 0484 Oslo, Norway b Institute of Transport Economics, Gaustadalléen 21, 0349 Oslo, Norway ⁎ Correspondence 8 12 2022 12 2023 8 12 2022 5 100102100102 11 5 2022 25 11 2022 2 12 2022 © 2022 The Author(s) 2022 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. The purpose of this study is to investigate how the COVID-19 crisis affected delivery security and firms’ preparedness and responses in Norway. Investigations focus on supply chains which were critical for maintaining the supply of essential goods when large parts of society closed down. This includes four firms belonging to food and pharmaceutical industries, representing different parts of the respective supply chains, and covering imports, exports, domestic distribution, and home-delivery services. The originality of this article is that we employ theoretical models on supply chain risk management, resilience and reliability in conjunction, where these are usually used separately. Recognizing links, overlaps, and complementarity between the models, and using them step-by-step, we exploit synergies that enable more comprehensive assessments of strengths and weaknesses in firms’ supply chains, covering gaps, prioritizing between improvement areas, and collecting input towards detailed, actionable risk mitigation actions. Investigations build on semi-structured interviews, systematically covering the formative elements for each of the models. Using the models in conjunction, we compare the firms and identify differences, similarities, strengths, and weaknesses in the consequences of pandemic-related disruptions and how firms approached the challenges. The main challenges for the firms were sudden demand changes early in the pandemic. While the firms had minor differences, their pre-pandemic contingency plans were generally not actionable or detailed enough, nor prepared for the pandemic's longevity. Therefore, more detailed and long-term guidelines are desirable, noting the importance and interrelationships of elements of supply chain risk management, resilience, and reliability. A common feature for all firms, and crucial for handling disruptions, is the importance of good and long-term relationships with upstream and downstream supply chain partners and the need for improving contingency plans and future resilience. Keywords Supply chain risk management Supply chain resilience Supply chain reliability Contingency planning COVID-19 Food supply chains Pharmaceutical supply chains ==== Body pmc1 Introduction The COVID-19 pandemic is unprecedented in modern history and the disruptions it has induced have had profound impacts on global supply chains in both upstream and downstream operations [1]. Araz et al. [2] considered COVID-19 the most severe supply chain (SC) disruption the world has experienced in decades, and examples of unexpected challenges include demand and supply shocks related to hoarding, (foreign) labor shortages, and cross-border transportation restrictions [1,3,4]. When COVID-19 hit Europe, the business community was unprepared for its ramifications. Although firms usually have contingency plans, few foresaw the possibility of a pandemic or dealing with the types, combinations, and longevity of challenges the pandemic caused [4]. This necessitated more ad-hoc responses than might be desirable, often based on little information and preparation, and led to increased uncertainty. The current article investigates how the COVID-19 crisis has affected the risk, resilience, and reliability of supply in food and pharmaceutical supply chains, industries that had to maintain the supply of essential goods when society otherwise closed with the first infection outbreak. We investigated four firms, all major players in their respective sectors in Norway. Our objective was to provide insights into successful and unsuccessful strategies for firms under pressure, the challenges that they faced, best practices, and recommendations for handling current and future situations. As such, this article contributes with lessons from the current crisis that may not only make supply chains more resilient and robust to future pandemics, but also to other economic shocks where similar patterns may occur, such as natural disasters. In all, the article's overarching research questions can be summarized as follows:- How did COVID-19 disruptions affect Norwegian food and pharmaceutical supply chains?○ How did firms in these supply chains approach risk, resilience and reliability of supply? ○ How were delivery security and firms’ responses affected by the crisis? ○ What lessons can be drawn from the pandemic to make supply chains and contingency plans more resilient and robust? Our investigation is based on three theoretical models for supply chain analysis, which we utilize as tools for assessing and comparing how (1) risk, (2) resilience, and (3) reliability have affected supply chains for each of the four firms. These three models are often used separately (e.g. Fan and Stevenson [5] or El Baz and Ruel [6] for supply chain risk; Pourhejazy et al. [7], Ali and Golgeci [8] or Stone and Rahimifard [9] for supply chain resilience; Kano and Oh [10] for supply chain reliability). Recognizing several links, overlaps, and complementarity between the models, and using them step-by-step, this article exploits synergies that enable a comprehensive assessment of strengths and weaknesses, and suggests how the firms may become more prepared for future disruptions. Learning from the current pandemic is important for several reasons, the most obvious of which is better future preparedness. While the last pandemic with comparable severity and scale to COVID-19 (the Spanish flu) occurred more than a century ago, epidemics with potential for long-term disruptions, high uncertainty, and unpredictable scaling have been more likely to occur since then as a result of increased globalization, population growth, and density increases [11,12]. At the same time, new challenges often go hand-in-hand with new opportunities, such as when disruptions lead to innovation or enable firms to gain competitive advantages and attract new customers during difficult times [12]. Lessons from such occurrences may also be valuable. While the current article has a Norwegian perspective, reports throughout the pandemic suggest that SCs in many other developed countries face many of the same issues (at least partially). In this regard, particularly the investigation of major transport buyers, who are highly dependent on foreign sourcing and supply chains, can contribute to more generalizable and transferable results and lessons, such as those related to pharmaceutical and hospital supplies, as well as food distribution. The present study demonstrates the synergy of using three theoretical models for SC analysis alongside, rather than separately, as is the standard in most literature. In doing so, this article helps improve future preparedness and contingency plans and provides improved insights into the interrelationships among risk management, resilience, and reliability. This can help firms establish broader, more comprehensive overviews of their strengths and weaknesses, cover gaps in contingency plans, prioritize between improvement areas, and formulate actionable risk mitigation actions. 2 Theoretical background Supply chain disruption can be defined as “an indication of a firm's inability to match demand and supply”, with widespread recognition existing of the negative impacts of disruptions on the economy ([13], p.35). Ellis et al. [[14], p.35] posited that SC disruptions are “unforeseen events that interfere with the normal flow of goods and/or materials within a supply chain”, while Hendricks and Singhal [15] explained supply disruptions as glitches that can affect both the short- and long-term profitability of firms. For supply chains covering food and pharmaceutical products, supply chain disruptions can, in severe cases, directly affect food security (e.g. [16]), life, and health. The pandemic has induced a surge in policy attention for these topics, including in Norway (e.g. [17]). In order to help firms become more prepared to handle uncertainty, and thereby become more robust, scientific literature has contributed with theoretical models on supply chain risk management, resilience and reliability, respectively. The current article employs these models to provide insights on firms’ strengths and weaknesses, which can then be used to improve contingency plans, so that firms are more prepared if and when new disruptions materialize. 2.1 Risk management Supply chain risk management (SCRM) is an important tool when experiencing disruption and can help reduce the likelihood and severity of potential risk scenarios occurring in SCs. Research shows that authors have diverse risk definitions for different parts of the SC [18]. Based on their review, Ho et al. [[18], p.5035] defined SC risk as “the likelihood and impact of unexpected macro- and/or micro-level events or conditions that adversely influence any part of a SC leading to operational, tactical, or strategic level failures or irregularities”. Therefore, SCRM will have a broader scope than just a single firm and should account for how processes work between entities involved [19]. There must be an integrated process with risk management culture in focus and clear leadership by senior management [20]. Christopher and Peck [21] defined four types of risk within SCRM: supply risk, process risk, demand risk and control risk. During the COVID-19 pandemic, firms/establishments focused mostly on supply, demand, and control risk [22]. Supply risk refers to how dependent firms are on certain suppliers [23]. Demand risk during COVID-19 refers to spikes in demand and consequent bottlenecks. For example, sudden demand spikes led to SC bottlenecks, with several suppliers unable to deliver as expected. Bottlenecks were also a challenge related to supply risk as many plants closed down for short amounts of time, before opening up again and producing more than ever, without sufficient logistics capacity for delivering produced goods [22]. Finally, control risk is the ability to engage suppliers in the response to the pandemic (ibid). SCRM plays an important role in enhancing SC resilience, and consists of a process with interconnected steps. A literature review [18] identified the following four steps as most common in SCRM approaches:- Step 1, risk identification, is crucial to manage risk [18,24]. The aim is to identify all relevant risks and recognize future uncertainties, in order to successfully implement proper SCRM (Fan and Stevenson [5]. Risk awareness is key to being able to manage and understand how to mitigate risks [25]. - Step 2 entails risk assessment and placing risks in a prioritized order based on their likelihood and severity [6,26]. It generally builds on assessments using relevant data, expert opinions, or scenario thinking and also lays the basis for the two subsequent steps [5]. - Step 3, risk mitigation, focuses on reducing risks to acceptable levels by using different strategies [24,26]. - Step 4, riskcontrol, is important in order to monitor identified risks in case their status changes [5,6,24]. El Baz and Ruel [6] showed that the four SCRM steps have a positive effect on SC resilience. 2.2 Resilience Resilience is a confusing and contradictory concept that not even well-developed disciplines manage to define [27]. In SC terms, it can be summarized as a SC's ability to manage inevitable risk and still move forward and return to a desired situation [21,28] or “the adaptive capability of the SC to prepare for unexpected events, respond to disruptions, and recover from them by maintaining continuity of operations at the desired level of connectedness and control over structure and function” ([27], p.131). SC resilience is often discussed through certain formative elements. Jüttner and Maklan [29] explained four central elements: collaboration, visibility, flexibility, and velocity. In short, collaboration is the element influencing all other elements and ensures that elements are adopted by all parties in the SC [30]. Visibility focuses on the overview of the whole chain, how fast the SC detects signals, and the ability to share information [29]. Flexibility refers to the ability to adapt to both positive and negative impacts and the SC effectively absorbing these [27]. Velocity refers to how efficiently SCs react and recover from disruptions in SC processes [29]. Driven by significant breakthroughs in management thinking, the way that firms compete has evolved; from competition against firms, towards competition against SCs [31]. This development has increased the importance of collaboration across SC entities generally, but also the great essence of collaboration for SC resilience [19,21,32]. To build resilience, organizations in SCs need to collaborate and view the chain with a holistic approach [30]. Therefore, effective sharing of information and coordination have become important areas for risk handling, but require trust, collaboration, and commitment from involved parties [33,34]. Good coordination, collaboration, and communication and relationships with actors up- and downstream the SC will contribute to proactively enhance SC resilience – for example, by improving/steadying service levels and reducing misunderstandings – because all actors will better understand end customers’ demands [4,34]. Also SC visibility is considered to be extremely important when facing disruptions. Visibility is the ability to share information across the SC, with timeliness and accuracy of this information being important (Barratt and Oke, 2017; [35,36]). Visibility can enable stronger relationships throughout the whole SC and contribute to better collaboration and higher levels of trust [35], although to improve operational efficiency, a prerequisite is that information is used well [36]. During the COVID-19 pandemic, visibility has been shown to be positively correlated with resilience [37]. With regard to flexibility, recent findings indicate that the firms that were the most resilient during the pandemic were the ones that were flexible [38]. The relationship with uncertainty can be pointed out because flexibility forms a direct response to changes in the existing situation [39]. Finally, velocity relates to the speed with which SCs are able to change, recover, and adapt to new desirable states [21,27,29,40]. Therefore, velocity a capability that is especially needed when encountering disruptions in a SC [40], and can, provided sufficient and correct information, reduce response and recovery times [30]. 2.3 Reliability For SC reliability, three distinct key elements are delivery reliability, customer relationship and supplier relationship. When choosing suppliers, reliability is a key factor [41]. Reliability can be defined as “the probability that all the required materials and products flowing through a supply network will arrive at their destination in a specified interval under stated conditions” ([42], p.264) and is key to ensuring both effectiveness and efficiency [43]. Research has argued that strong relationships with a few suppliers strengthen reliability more than weak relationships with several suppliers [44]. To enhance resilience, SC relationships must also be robust and reliable. Reliable relationships can be built through collaboration, which builds on trust and enables flexibility when unexpected market changes occur [4]. Although SC reliability is not a new area of research, interest in the subject has spiked recently, as the need for reliable deliveries of essential supplies became a focal theme globally [45]. During the pandemic, lead times for certain items became longer than expected [6] and in some areas, customer confidence in the ability of SCs to deliver has decreased [4]. Studying disruptions in relation to SC reliability, Chen et al. [46] found that for short-term disruptions, emergency procurement is a recommendable strategy, while for long-time disruptions, a combination of emergency procurement and a change of products is advised. Reliability has a close connection with several elements of resilience. For example, long and trusting relationships with suppliers can contribute to good collaboration and flexibility, thereby enabling reliability. Reliability is also a two-way relationship between supplier and customer roles; being a reliable supplier is dependent on the reliability of one's own suppliers. 2.4 Contingency plans To be better prepared for adverse events, many firms develop contingency plans that are meant to help them respond effectively to unfavorable or emergency situations that may or may not occur in the future [47]. Contingency plans mitigate impacts of unexpected incidents and outline strategies for ensuring business continuity (see e.g. [48]) and continuing daily business operations. These plans should be well-defined, with actionable points and clear instructions on how to prioritize [49]. Regarding emergency response preparation, SC literature refers to planning as an important strategic priority in crisis management, with the pandemic putting the need for holistic approaches to contingency planning high on the agenda [11,50,51,52]. SCs can mitigate risk and expedite disaster recovery by being proactive and investing in contingency plans, and can strengthen SC resilience by enabling the SC to turn around quickly and adapt pre-developed contingency plans to the current disruption [53]. However, creating the perfect contingency plan involves certain difficulties, since the world is constantly changing, and so are the potential risks. Other challenges are balancing the costs of preparing for all potential risks and the benefits of preparedness. According to Fernandes and Saldanha da Gama [53], while costs of planning for disruptions can be high, the consequences of not having a contingency plan can be disastrous. While SC literature emphasizes the value of having a contingency plan, the reality is that far too many contingency plans are created and then sit dormant for extended periods of time, possibly becoming irrelevant when disruptions of low predictability and high severity arise [52]. A contributing factor is that responses to such disruptions are shaped by human's complex attitudes towards risk perception and management [54,55] and inter-human attitude variations [56]. Therefore, frequent updates of contingency plans, as well as employee involvement in the updates, are crucial to keep SCs prepared for disruptions. The COVID-19 pandemic has demonstrated both the lack of contingency planning and the limitations in contingency planning for extreme events (e.g. [48]). To better manage risk in the event of disruptions, factors such as labor shortages, inventory shortages, procurement, and logistical challenges in the SC should be evaluated in the contingency process and considered in the contingency plan. Post-pandemic, SCs should further review and iterate the contingency plan [4]. 3 Materials and methods 3.1 Analytical framework We employed the three theoretical models discussed above as tools of analysis for assessing and comparing how (1) risk, (2) resilience, and (3) reliability have affected supply chains for each of four firms, using input from semi-structured interviews (see the following sections). Fig. 1 provides a stylized illustration of the analytical framework of the current article. Hereby, we recognize that there are strong links between the models and that they are to some extent complementary, both in terms of overlaps (depicted in the figure) and in terms of possible synergies when employing the models in conjunction. Elements on the outside of the circles represent the formative elements of the three models and illustrate the relationships and linkages between these elements for each of the models individually. For SCRM, these are the four different consecutive steps. For resilience, these are visibility, flexibility and velocity, with collaboration influencing all other elements and ensuring that elements are adopted by all SC partners [30]. For reliability, the elements ‘customer relationships’, ‘delivery reliability’, and ‘supplier relationships’ are all interrelated.Fig. 1 The three theoretical models for supply chain analysis, the relationships between their steps and sub-elements, the complementarity and overlaps of the theoretical models, and their insights feeding into improved contingency plans. Fig. 1 Considering the models together, there are strong linkages and interactions between formative elements of resilience and reliability, and these, in turn, build naturally on the steps of the SCRM and its four discussed risk types (supply, process, demand and control risk). In conjunction, the models can provide comprehensive insights on strengths and weaknesses for the firms and interrelationships between these. Such insights can then be used as inputs for improving contingency plans and firms’ future preparedness by covering gaps in current plans, and by allowing comprehensive prioritization of improvement areas and formulation of actionable points. Running through the models in conjunction, and step-by-step, helps to ensure that contingency plans can become both more comprehensive and detailed, can increase awareness, and reduces the risk of inadvertently leaving out important elements by effectively providing a ‘checklist’. By systematically addressing all of the three model's steps and sub-components for each of the investigated firms, they can further be compared with each other, and differences and similarities can be identified in terms of how they were affected by pandemic-related disruptions and their approaches to these challenges. 3.2 Firm description and background When the first wave of infections hit Norway, the country's government decided to shut down large parts of society, including shops, cafes, restaurants, and cultural life. Exemptions were made for grocery stores and pharmacies, which were deemed essential to keep society going, as was the safeguarding of necessary hospital deliveries. In analyzing the vulnerability of SCs in relation to the pandemic, the research project underlying the current article focused on covering SCs for essential goods (food and pharmaceuticals) and SCs from the supply side (production and import) to exports and domestic distribution, as well as last-mile and home deliveries, and thereby to obtain a 360-degree perspective. The current article is based on investigations of the four suppliers participating in the research project. Of these, three are actors in (fresh) food supply chains (FSCs) as producer and exporter, importer and distributor, and distributor for home deliveries, respectively. The fourth firm is an actor in a pharmaceutical supply chain (PSC) that imports pharmaceutical products and distributes them to pharmacies, hospitals and municipalities (nursing and retirement homes) throughout Norway. Table 1 provides a summary of the characteristics of each firm, which are referred to hereafter as (1) fish farming firm, (2) food distributor, (3) home-delivery firm and (4) pharmaceutical firm. While the analysis has a Norwegian context, the firms investigated have dominant market positions and operate in an international market. This makes their SCs extra vulnerable, but also adds an international perspective to the analyses. It can be noted that turnover per employee increases from left to right in the table, illustrating each firms’ placement within SCs and the high unit values of pharmaceutical products.Table 1 Overview of each investigated firm's broad characteristics. Table 1 Fish farming firm Food distributor Home-delivery firm Pharmaceutical firm Type of organization Global group National group National group Global group Trading product Farmed fish Perishable goods Groceries Medicines and pharmaceutical goods Role in value chain Producer Distributor Last-mile Distributor Main market upstream Domestic Abroad Domestic Abroad Main market downstream Abroad Domestic Domestic Domestic Turnover per employee, 2020, million NOK (rounded)* 3.3 6.7 8.3 45.0 Number of employees >5,000 <5,000 <500 <500 Establishment 1992 1914 2013 1995 ⁎ Average exchange rates for 2020 (2021): 1 EUR ≈ 10,72 (10,16) NOK; 1 USD ≈ 9,95 (10,17) NOK. Generally, FSCs have increasingly become more complex and diverse due to globalization, enabling people all over the world to eat food that is grown (and produced) in other climates than their own. Today, a (simplified) FSC essentially consists of five entities: producer, processor, distributor, retailer, and consumer. For FSCs, important aspects are how globalization has affected food security, safety, and integrity [57]. The main difference between normal SCs and FSCs is the continuous change in the quality of products in all joints between producer and consumer [58,59]. Furthermore, the availability of temperature-regulated transportation and shipping options throughout SCs is often an important factor [60]. FSCs can face challenges in every part of the SC, and this complexity can make FSCs vulnerable in times of crisis. Therefore, these SCs require agility in order to meet customers’ demand in normal times, and resilience in the face of disruptions [61]. A PSC is “a special SC in which medications are produced, transported and consumed” (Xie and Breen, 2012, p.41). While there are many variations of the structural PSC, this study will use the simplified SC demonstrated for FSCs, as it creates a common understanding when later comparing the four firms. PSCs are global, complex, and strictly regulated. Pharmaceutical products also need temperate-regulated transport, and often have short shelf lives. The COVID-19 pandemic affected every part of the FSC and PSC. Overseas markets and sourcing locations have been challenging to reach due to collapses in passenger flights and price rate increases for freight flights and international container shipping, while also closed borders have affected transportation times. Domestically and internationally, FSCs have experienced demand shocks from grocery stores, alongside steep demand reductions in, for example, the HORECA sector (hotel, restaurant and café) or food services market (e.g. [3,4]). PSCs experienced challenges long before the pandemic outburst (for example, drug shortages and delivery problems throughout the globe) and vulnerabilities became more apparent in the midst of it, with hoarding and general demand increases putting extra strain on already fragile PSCs. While shortages of supply in some SCs have caused no trouble other than extra waiting time, shortages in PSCs can put health and human lives at risk. 3.3 Data collection Data collection was based on semi-structured interviews with key logistics staff at all four firms. Each firm was interviewed at least twice (around New Year 2020/2021 and in spring/early summer 2021) to capture both early experiences and new(er) challenges and developments. Interviews followed a general interview guide, which was adjusted to fit each firm's SC role. All interviews were structured in the same way and addressed the same topics, revolving around the formative elements of the three theoretical models for SC analysis summarized in Fig. 1. Questions were open-ended and differentiated by category to identify (1) how prepared the firms were for a state of emergency such as the pandemic (what was set out in their contingency plans?); (2) to identify the main SC risk factors and approaches to risk assessment, mitigation and control; (3) How reliable their security of supply was; and (4) how resilient the firms were in periods with outbreaks and/or market shortages. Examples of interview topics include the existence of any contingency plans and details on their scope, infection control measures, any staffing challenges or solutions, market and demand dynamics, changes in demand for and organization of transport, changes in transport and logistics costs, different themes regarding any operational changes/adaptations, use of foreign workers, challenges and solutions related to border crossings, implications for the firms’ economic situation and investments, implementation of new solutions, and whether the pandemic changed the firms’ approach to robustness in the longer term. In addition, specific pandemic-related cases occurring at some firms were discussed, and all firms were given an opportunity to bring up additional topics they considered relevant. All interviews were transcribed and sent to the interviewees for fact-checking, correction of any misunderstandings, and approval. Interview feedback was then categorized based on the formative elements of the three analytical models. By approaching analyses in this way, we sought to satisfy objectivity, auditability, validity, and application criteria for qualitative data analysis [62]. Based on the above, Fig. 2 provides a comprehensive overview of the current study's methodology and analytical steps.Fig. 2 Overview of methodology and analysis steps. Fig. 2 4 Results The current section presents findings from interviews for each of the four firms. Hereby, we follow the three key analytical models for supply chain risk management, resilience and reliability, and their multiple elements and steps. The main findings regarding each of the models are summarized in Tables 2 , 3 and 4 , each of which is followed by more in-depth findings descriptions.Table 2 Main findings on the four steps in the supply chain risk management process. Table 2 Fish farming firm Food distributor Home-delivery firm Pharmaceutical firm Identification Overarching capacity evaluation pre-pandemic. Identification of supply base risk after pandemic reached Norway Investigation of how the pandemic would affect the firm started in January 2020, including risk evaluation of (how) whether the virus could spread through food Establishment of crisis management team after pandemic outbreak Continuous monitoring of risks already in place pre-pandemic Assessment Ability to rapidly assess risks, but dependent on proper identification. Less formal implementation of risk identification and assessment in routines Assessment and ranking of all identified risks. Some risks discarded/ downgraded, others (e.g., supply risk) highly prioritized Contingency plans for different risk scenarios Frequent assessment of identified risks and prioritization thereafter Mitigation Some lack of established plans/mitigation for risks inherent in the firm's SC and capacity limitations. Some extent of (rapid) ad-hoc mitigation Plans for most identified risks, e.g. food security and supply base. Sketch of what to do in case of main terminal closure (not necessarily detailed plans with actionable options) Contingency plan covering several risk scenarios Strategies for different risk scenarios Control (Continuous) monitoring of staffing capacity risk. Challenges during first days of each new infection wave. Improved control during later waves vs. first wave Monitoring of different risks throughout the pandemic. Continuous tweaking to keep routines and procedures up-to-date Close monitoring of the situation. Prepared for different alternatives, if needed (Continuous) monitoring of identified risks. Special focus on trends relevant also pre-pandemic Table 3 Main findings on the four elements of supply chain resilience. Table 3 Fish farming firm Food distributor Home-delivery firm Pharmaceutical firm Collaboration Well-established network in export markets. Assistance from customers in relocating fish products from HORECA to retail market Assistance in transferring excess products from HORECA to retail market. Assistance from a foreign factory and local producers during outbreak at one own factory Collaboration with suppliers, but the firm experienced being downgraded/not prioritized during periods with shortages of goods due its relative size vs. other actors Assistance from international parent company Visibility Control over entire value chain and locations worldwide. Improved visibility considered important; plans for improvement using more/better IT Good flow of information to/from both suppliers and customers. Some desire for more forecasts for planning ahead Good information flow with customers. Uncertainty about deliveries from some suppliers. Generally good visibility in internal systems Updates on demand increases and bottlenecks throughout pandemic Flexibility Adjustment of volumes of fish going into production (e.g., slow down production). Further flexibility through use of smokehouses Several suppliers for most products. Tackled large shift in demand. Flexibility in some new routines (terminal, delivery timeframes) Rapid capacity increases, changed delivery time slots and some delivery procedures, expanded delivery areas Medicine procurement from open market possible, if needed (often expensive). Flexibility through procedures for prioritizing critical vs. non-critical goods Velocity Rapid adaption to new situation by delaying production speed. Turnover challenges due to fall in important HORECA market Fast action in moving excess goods from HORECA to retail, despite this necessitating extra processing steps. Rapid solutions after a factory closure Fast capacity increases both during 1st and 2nd infection waves. Capacity challenges still occurred, but less so during 2nd and later waves Fast adjustment to new situation, reaching satisfactory levels Table 4 Main findings on the three elements of supply chain reliability. Table 4 Fish farming firm Food distributor Home-delivery firm Pharmaceutical firm Delivery reliability As supplier: delivery was reliable, managed, i.a. through changing production speed. Delivery to customers in some countries was negatively affected due to transport challenges Had to allow slightly longer delivery times from Southern Europe. Accommodation of demand shifts through delivery of alternative products. Hoarding and temporary factory closing caused some empty shelves in stores Sold out-situations for some products. Back-orders many days ahead due to capacity constraints Sold-out situations due to medicine hoarding around first lockdown, followed by demand fall; challenges for both the firm and transport providers, but managed relatively rapidly. Reduced domestic air capacity tackled by more slack in transport schedules Customer relationship Good and well-established relationships with customers: customer retention and customer help in transferring products from HORECA to retail markets Assistance from retail market customers in transferring much of excess HORECA products to retail Customer loss in HORECA and business market. Improved solutions for private consumers; e.g., implementation of contactless deliveries/solutions for people in quarantine/isolation No problems with loss of customers or bad relationships. Medicine shortages could affect customer relationship negatively Supplier relationship Firm with largely a supplier role. Much use of air freight and international road freight. Long-term contracts with carriers, but price increases, particularly for air freight, mostly set by market Several alternative suppliers for most products, often long, collaborative relationships (a few product groups with just one supplier). No ‘COVID-19-compensation’ of suppliers, despite some suppliers’ demand Mostly local/ Norwegian suppliers. In-house carriers, complemented with some external delivery hire-ins. Considered a relatively small actor by suppliers Relatively few problems with procurement. Good cooperation with international parent firm. No payment of higher rates, despite demands from carriers supplying transport service, arguing pandemic-related cost increases 4.1 Risk management 4.1.1 Identification While all four firms have an identification phase in their risk management approaches, this phase was most extensive for the pharmaceutical firm and the food distributor. The pharmaceutical firm employs a process for continuous risk identification and focuses on identifying risks at an early stage, while the food distributor started an extensive risk identification process in January 2020, before the pandemic hit Norway. The home-delivery firm, in turn, identified capacity risks (staff, transport, etc.) pre-pandemic, but had less focus on or only later identified other risks (such as supply base risk). The fish farming firm identified and to a large degree focused on a specific set of risks (such as price and biological risks) with less thorough identification of other risk types, especially operational and market risks. Because risk identification is a prerequisite for assessing, preparing for, mitigating, and controlling risk, starting early or continuous risk monitoring (such as done by the food distributor and fish farming firm) can be beneficial – although overdoing this can also be costly. The home-delivery and the fish farming firm could have benefited from broader or earlier identification of other risks than the ones focused upon, such as by improving preparedness or having “bought more time” than when risks are first identified when they are about to materialize. 4.1.2 Risk assessment Risk assessment is also incorporated to some extent in all the four firms’ approaches to risk management. Risk assessment seems to be a more continuous process at the pharmaceutical firm and the food distributor, where risks were ranked and then (re)prioritized, while the fish farming firm's assessment phase seems somewhat less continuous and, to some extent, reactive, with risks identified upon materialization. The home-delivery firm assessed risks quickly once identified, but with initial focus on capacity, several other risks were first identified and assessed after the pandemic hit. Feedback further revealed that three of the firms considered that their approach to risk assessment benefited from previous experiences with disruptions and previously established risk scenarios. It was further noted that, in retrospect, it would have been wise to put more resources into assessing certain risks (such as a potential shutdown of the food distributor's main terminal), but also that a balance must be struck between costs and benefits of extensive identification and assessment processes. 4.1.3 Risk mitigation Although not all firms had mitigation strategies for direct pandemic risks, they did all have, to some extent, strategies for other risk scenarios that were relevant considering pandemic disruptions (such as transportation issues or temporary closure of facilities). The food distributor and pharmaceutical firm had mitigation plans for different risk scenarios; for example, concrete options in case of capacity problems, alternative suppliers, and food security. However, mitigation alternatives in case the food distributors’ main terminal should be closed would likely have been suboptimal and presented challenges, while mitigation responses to initial medicine hoarding were largely successful (only short periods with lower service levels), but still suboptimal from a business perspective, as servicing peaks is expensive. The home-delivery firm faced capacity issues immediately after the first Norwegian lockdown in March 2020 due to the sharp growth in demand for home deliveries. While responses were rapid and mitigation plans were in place for hiring staff through employment agencies, some practical issues occurred (such as lower staff availability than expected) and mitigation was initially insufficient to keep up with extreme demand increases. As part of one ad-hoc mitigation measure, the firm rapidly (within a few days) introduced a standardized box with products considered most essential/demanded. It was possible to process this box at a separate location and in an efficient way, thereby lifting some capacity pressure. Further, the firm did not foresee that some product supplies would not be delivered and that suppliers would not prioritize them during a crisis, and did not have mitigation measures prepared. On the other hand, the firm reports that it was able to improve mitigation plans throughout the pandemic, which enabled it to handle later waves of infections better. The fish farming firm was able to act quickly, utilizing flexibility of delaying production by postponing the gutting of fish or sending fish to smokehouses for preservation. This provided flexibility in case of sudden demand drops for fresh fish or transportation challenges. However, challenges related to reduced belly-capacity for air freight due to loss of passenger flights on some overseas routes with too-small volumes for dedicated cargo flights, followed by sharp increases in transportation prices, were not mitigated as efficiently as hoped. 4.1.4 Risk control All four firms have been monitoring risks throughout the pandemic to be prepared for risks changing fast or suddenly becoming severe. For example, the food distributor continuously tweaked and strengthened routines and procedures and ensured these remained up-to-date. The pharmaceutical firm continuously monitored identified risks, including transport, by such means as considering capacity and by tracking of transport routes. Due to the critical nature of the firms’ activities and trends of global medicine shortages already pre-pandemic, this risk received focus. Around the time of the first Norwegian lockdown, some sold-out situations materialized after extensive medicine hoarding by consumers. This was not the case in later waves, both due to better preparedness, consumers realizing that supply would be sufficient, and people not suddenly becoming ill more often. The home-delivery firm closely monitored capacity risks and, as a result, improved its mitigation strategies. While new waves still yielded short-term capacity challenges, these were considerably less substantial than they were around the time of the first Norwegian lockdown. 4.2 Resilience 4.2.1 Collaboration For the food distributor, good collaboration contributed to resilience in several ways. The firm has strong, long-term, and collaborative relationships with key suppliers and was prioritized during difficult times, while examples were given that this was less the case for actors with supplier-buyer relationships focused mainly on pricing. Similarly, good relations with its own customers allowed agility when the need arose to rapidly shift large quantities of products from HORECA to retail. During an infection outbreak that necessitated a short closure of an own factory, local suppliers and a foreign factory quickly stepped in. The home-delivery firm, in turn, struggled to match supply and skyrocketing demand. The firm was not prioritized by its main supplier, and also some other suppliers provided low service levels. Initiating closer collaboration with several of the latter suppliers, the firm managed to increase service levels from as low as 70 percent up to 99 percent. For the pharmaceutical firm, strong supplier relationships globally were critical during the pandemic, as the pandemic impacted the production, supply, and distribution of pharmaceuticals and caused bottlenecks in global supply chains. A complicating factor is that frameworks set by Norwegian authorities effectively determine which manufacturers are relevant to consider. Therefore, manufacturers that are “not on the list”, even with good long-term relationships with the pharmaceutical firm are, in practice, not chosen. This framework makes it harder to build collaborative relationships based on mutual trust and shared interests. While the above three firms have large buyer roles, the fish farming firm, covering the entire value chain from feed to finished product, is primarily a global supplier. In this role, strong relationships with customers helped transfer a lot of products to other markets. Further, the Asian HORECA market did not shut down the same way as in Europe, and in part due to close collaboration, many products could still be delivered. Experience from previous air freight disruptions and collaboration with customers also gave some knowledge edge on maintaining good collaboration during crises. 4.2.2 Visibility The food distributor focused on consistent, timely, accurate, and open communication with both suppliers and customers. While deliberately choosing not to share too much information, information sharing has increased compared to pre-pandemic. Throughout, it has become clearer which information must be shared, such as for planning and monitoring. The home-delivery firm has a dedicated department for collecting and analyzing important data. This department is central in terms of enhancing visibility internally and for external partners, and data collection and analyses have increased to yield more insights. Good information flows with customers also improve delivery efficiency. However, a lack of correct visibility or receiving incorrect information from suppliers led to stock-outs of products already ordered by customers. Further, supplier information often only arrived for the first time when it was asked for. The food distributor also experienced not receiving enough useful information or receiving unnecessary information. Overall, the firm started sharing more information themselves than it had previously and reported that this had positively benefited it and its surroundings. The fish farming firm started implementing systems to enhance visibility, especially in real-time. Examples include tracking of temperature and visibility (traceability) of orders for customers. The pharmaceutical firm's systems are partly synchronized with its parent company's and automated procurement enables the optimization of entire supply chains and full control over fill rates and stock quality. Information sent to customers is said to be good, but information from suppliers is not always accurate or complete. 4.2.3 Flexibility The food distributor and fish farming firm experienced lower demand when the pandemic hit, while the home-delivery and pharmaceutical firms experienced demand increases. The food distributor managed good volume control and was able to redirect most excess products to the retail market when HORECA/business markets plunged, although some food had to be given away or discarded. Further, the firm was able to rapidly respond to shifts in types of products demanded by consumers, meaning procurement of different kinds of products from suppliers at short notice. The firm also managed to deal with longer lead times from Southern Europe and with necessary changes to procedures at both its own and the suppliers’ terminals. While the home-delivery firm was somewhat overwhelmed by massive demand increases immediately after the first Norwegian societal restrictions, it did manage to increase capacity substantially in the course of few weeks in terms of staff, vehicles, and longer delivery windows. During later demand peaks, the firm was able to scale up relatively well and was prepared for new demand increases that it expected in relation to government press conferences on restrictions. For the fish farming firm, flexibility was relatively good through help of customers worldwide in redirecting high-quality seafood to retail and by changing production speed (such as feeding rates, postponing slaughter, etc.). The availability of alternative facilities along the Norwegian coast also offers flexibility if a specific facility would suddenly have to close. For air freight abroad, freight capacity to countries with large demand volumes mostly remained sufficient (but at high prices), but for lower-demand countries (reliant on passenger flight belly-capacity), deliveries in earlier phases of the pandemic had to be cancelled. The pharmaceutical firm had procedures to quickly implement prioritization of critical goods capacity at the expense of non-critical goods, and for getting in temporary staff in case supply and delivery of critical goods was at risk. Normally, automatic procurement systems ensure flexibility and preparedness by matching customer demand and volumes procured. However, extreme medicine hoarding around the first Norwegian lockdown led to systems interpreting this peak demand as a ‘new normal’, requiring manual corrections. The firm further responded to reduced domestic flight capacity by rescheduling their air freight transportation and adding more ‘slack’ in time schedules. For all firms, infection outbreaks at important terminals could have caused substantial problems, despite available (suboptimal) fallback alternatives. Feedback also indicates that strong, long-term relationships with suppliers and customers positively impacted flexibility and resilience, while short or weaker relationships at times have created challenges. 4.2.4 Velocity The food distributor and fish farming firm were able to quickly redirect products from markets in decline to retail, and in part to switch between product types. The firms’ flexibility and quick responses likely shortened their recovery times or reduced negative impacts of pandemic disruptions, and had the firms adapt to new environments and demand. Still, demand dynamics had an impact on turnover, because the reduced markets normally buy finer and more expensive products, while increasing (retail) markets are more quantity-driven. This applied especially to the fish farming firm. For the home-delivery firm, rapid responses and capacity increases enabled conversion of a large part of the huge demand increases into sales. Fast decision-making on increasing capacity also helped in terms of catching up on delays relatively fast. Velocity in information flows helped reduce the firm's recovery time. Although the firm expressed that, in hindsight, it would have made some hasty decisions differently, these examples illustrate the firm's ability to quickly implement solutions and adapt operations. The pharmaceutical firm largely handled the pandemic well, despite raw material shortages for pharmaceutical supplies that existed already pre-pandemic. Velocity was a theme with regard to suddenly procuring personal protective equipment (such as face masks) in large quantities at a time of extreme global demand. Further, the firm was able to quickly respond to medicine hoarding and consequent demand falls with regard to changing their use of distribution transport suppliers. 4.3 Reliability 4.3.1 Delivery reliability Both the food distributor and pharmaceutical firm managed to adjust well to changes in demand volumes and type of demand, with both having established long-term relationships with current key suppliers. While there were some sold-out situations, mostly related to higher-than-normal demand, these were managed relatively quickly. The food distributor had alternative suppliers for most products and incorporated slightly longer delivery times for produce from Southern Europe (cf. also e.g. [3]), without significant deterioration in delivery reliability. During the closure of one factory, delivery reliability was reduced for some products, but to a substantial extent managed through alternatives. The pharmaceutical firm proactively added time slack on domestic air freight deliveries, thereby ensuring reliable and in-time deliveries. The home-delivery firm, which relied heavily on just-in-time deliveries from suppliers, experienced reduced delivery reliability on products from some suppliers. This affected orders made by the firm's own customers. However, the firm offers similar products from different brands, and could often offer customers a relevant alternative product, rather than nothing. The firm's challenges are thought to be correlated with weaker or less-committal supplier relationships than for the other investigated firms. Both the food distributor and home-delivery firm experienced local outbreaks at facilities. The former managed to use alternatives, but the latter, while not closing down fully, did not have proper backup solutions. To ensure delivery reliability, the home-delivery firm tightened infection control measures and worked on hiring more people to take care of other parts of operations and who could be transferred in case of operational disturbances. The fish farming firm, as a supplier, managed reliable delivery of products throughout the pandemic by making production adjustments while minimizing waste and costs. Delivery reliability to consumers in certain lower-demand Asian countries was affected, but for countries with larger demand volumes (serviced using dedicated freight flights), this was not a significant problem. 4.3.2 Customer relationship Both the food distributor and fish farming firm expressed that they have well-established relationships with their customers and that customers helped them move products between markets. This willingness to help can be a sign of the desire to continue long relationships and also reduce uncertainty from suppliers [63]. While the home-delivery firm also lost much of its HORECA/business market, the private end-consumer market increased considerably. Unlike the markets for the food distributor and fish farming firm, these markets buy through the same platform, which meant that fewer changes were necessary. Solutions for order visibility and communication between carrier and customer about issues such as quarantines and delivery have contributed to reducing uncertainty and dependency related to grocery shopping in physical stores. The pharmaceutical firm reported very few challenges when it comes to its customers. There are well-established plans for what to do if some things cannot be procured, and which customers have seemingly agreed upon. This agreement makes orders predictable, with the firm being perceived as reliable. However, had substantial medicine shortages occurred and pharmacies, hospitals and end-consumers not received important medicines for critical time periods, this could have affected consumer relationships negatively. 4.3.3 Supplier relationship The food distributor has alternative suppliers to choose from for most products, with often long and well-established relationships, but for a few product groups only has one supplier. This resulted in challenges upon the abovementioned facility closure, but could also lead to challenges for other products. The pharmaceutical firm had few supplier problems and was helped and partly coordinated by its international parent organization. Both the food distributor and pharmaceutical firm were asked by carriers to increase transport payments, but neither were willing to agree to such requests. If transport suppliers should be paid too little, there is a potential risk in losing them if suppliers believe they can earn more elsewhere. However, the firms reported that not giving in to the carriers’ demands has not caused problems throughout the pandemic. It is unclear whether carriers might have attempted to exploit an extraordinary situation to extract higher margins, or whether alleged pandemic-related cost increases were indeed substantial enough to demand higher payments. The fish farming firm is highly dependent both on air freight for overseas deliveries (mainly to Asia and to some degree also North-America), but also on road transportation to the European continent. Despite often having long-term contracts, the firm faced high freight rates, especially for air transport, but also that it became challenging to cover the transport needs by truck. In all, the firms’ dependency necessitated the accepting of transport at much higher costs than pre-pandemic. The home-delivery firm had some trouble with suppliers during the pandemic. As a relatively small player in grocery retail, the firm is dependent on suppliers, but large Norwegian suppliers do not necessarily need the home-delivery firm to survive. Therefore, codependency is minimal, which could explain why the firm's increased demand was not prioritized by several suppliers. Creating a more codependent relationship might help improve this. A positive factor is that nearly all suppliers are Norwegian, which yields fewer challenges in the firm's own supply chain. 5 Discussion This article has assessed how pandemic-induced disruptions affected four firms in Norwegian food and pharmaceutical supply chains, how they approached supply chain risk management prior to and during the pandemic, and strengths and weaknesses of their SC's resilience and reliability. The objective of our investigations was to provide insights into challenges and opportunities during the current pandemic, and lessons for improving preparedness, resilience, and robustness towards future pandemics and shocks yielding similar disruptions and dynamics. Through several rounds of semi-structured interviews with each of the firms, we systematically addressed the main elements of three theoretical models for SC analysis. Using the models in conjunction, and given overlaps and complementarity between them, allowed us to provide comprehensive assessments of strengths and weaknesses of the individual firms, as well as common experiences, and to make suggestions for improving future preparedness. The four firms investigated faced different challenges, with the main ones materializing during the pandemic's earlier stages and particularly related to sudden demand changes. The food distributor, home-delivery firm, and pharmaceutical firm all experienced immediate and sharp demand increases due to panic responses in society and hoarding by consumers, although the former two firms also experienced (smaller) decreases from their business/HORECA segments. The fish farming firm, primarily directed at the global HORECA market, experienced immediate drops in demand from European and world markets. This necessitated an adjustment in production volumes and redirection of deliveries to the retail market and fish processing industry (at lower prices), resulting in temporary cash flow reductions. As has also been observed elsewhere (cf. [12]), these dynamics forced the firms to adapt both their SCs and product ranges (for example, smaller packages) from HORECA and to the retail markets. Regarding risk management, we found differences in the four firms’ scope, completeness, continuity, and timeliness of risk identification and assessment phases, with the pharmaceutical firm and food distributor identifying risks pre-pandemic or continuously, compared to some important risks for the home-delivery and fish farming firm first being recognized after the pandemic hit. While follow-ups in these cases were fast, they were also more reactive than desired and based on less rigorous analysis than usual underlying decisions (in line with observations by [22]). Furthermore, we found differences regarding how risk mitigation and control were approached, depending on how the previous SCRM steps were managed. Generally, however, all firms had mitigation strategies for some risks, albeit not directly for pandemic-specific risks. Many mitigation measures were relatively ad-hoc in early stages and then improved throughout the pandemic. A common factor here was the lack of actionable and sufficiently detailed points in the firms’ strategies and (contingency) plans. Interview feedback generally points to the importance of both sufficient and timely monitoring of potential risks, with risk assessment and control being up-to-date so that firms are more prepared for future disruptions (flexibility) and can act quickly when these disruptions materialize (velocity). Feedback suggests that, in retrospect, the firms would have put more resources into assessing certain risks. These findings are in line with El Baz and Ruel [6], who concluded that firms’ priority should be to develop efficient and updated risk identification measures, as these affect the other SCRM stages, and that firms need to develop interconnected SCRM practices to improve their robustness and resilience. Regarding supply chain resilience, we found differing extents of collaboration between firms and upstream and downstream parts of SCs. In particular, the fish farming and pharmaceutical firm and the food distributor highlighted good collaboration as an important factor for their resilience, while less established collaborative ties for the home-delivery firm were reported as a challenge. While the visibility of important information varied between firms, good visibility was reported to have helped resilience and decreased response time. Common tendencies across the investigated firms are an increased valuation of the importance of high-quality information, movements towards increasing information collection and analysis, and learning to focus and better distinguish between important and superfluous information. Confronted by disruptions, all four firms benefited from flexibility and responsiveness (velocity) in important parts of their activities and supply chains, either dampening potential negative effects (pharmaceutical and fish farming firm, food distributor), or successfully converting opportunities into value (home-delivery firm and personal protective equipment for the pharmaceutical firm). Researchers such as Hobbs [4] also highlighted such drivers in concluding that SC responsiveness is key for resilience. Simultaneously, underlying drivers (changes in demand levels and between demand segments) were largely beyond the firms’ control. All firms further worked to enhance digital communication skills, either before or during the pandemic. This allowed relatively smooth transitions to administrative employees working from home (flexibility), but also collaboration and visibility through more regular communication with external suppliers than pre-pandemic. Considering SC reliability, delivery reliability has been essential during the pandemic, with all firms experiencing increased lead times for certain items and customer confidence in the ability of SCs to deliver in some areas being decreased (in line with, e.g., Hobbs [4] and El Baz and Ruel [6]). While service levels towards customers were reduced to some extent and during some shorter periods for all investigated firms, reliable deliveries were largely maintained throughout the crisis. The same goes for transport (cf. also e.g. [3]), although this often required adjustment (such as new solutions when belly capacity onboard passenger flights suddenly disappeared for the fish farming firm). Regarding customer and supplier relationships, our investigations suggest a connection between long-term and trusting relationships and information sharing. The home-delivery firm experienced that its size and lack of long-term relationships and co-dependency meant that they were not always prioritized by suppliers, while the other firms gave examples of good long-term relationships with customers and suppliers having been success factors, both in transferring products between markets and in relation to local outbreaks at own facilities. In line with suggestions by Hobbs [4], long and trusting relationships have proven to contribute to good collaboration and flexibility, thereby enabling reliability. 6 Conclusion Overall, while the four investigated firms had contingency plans prior to the pandemic, these generally both had gaps and lacked the actionable points and level of detail reported to be desirable in retrospect (in line with broader industry observations by [22]). At the same time, detailed strategies were highlighted as important for being able to adapt quickly. 6.1 Implications Insights from this article can contribute to improving future preparedness and contingency plans in several ways by utilizing the three SC models in conjunction, and may have practical, research, and operational implications. Finding suggest that ongoing societal trends of facility centralization may add an element of vulnerability for firms, while spreading important functions over multiple locations can ensure more operational flexibility. The pharmaceutical firm, for example, accelerated the establishment of a planned emergency warehouse, where it originally operated from one large warehouse where infection outbreaks in the worst case could endanger distribution of critical products. Both the food distributor and home delivery firm demonstrated some flexibility in moving production to other facilities, but could have been affected more severely if outbreaks had occurred at more critical sites than was the case. 6.2 Theoretical and practical contributions From a research perspective, our study demonstrates the synergy of using three theoretical models for SC analysis alongside, rather than separately. This approach also made it possible to more comprehensively compare firms with each other and to extract insights on more general tendencies and lessons with relevance also for other firms. By systematically running through each of the models, interrelationships among elements of risk management, resilience, and reliability become more visible, increasing awareness and providing firms a ‘checklist’ that forces them to consider and incorporate specific dimensions. This enables firms to establish a broader and more comprehensive picture of their strengths and weaknesses, cover gaps, prioritize between improvement areas, and collect input towards formulating detailed, actionable points. 6.3 Limitations A limitation of investigations based on semi-structured interviews is that some bias may occur. For example, firms may want to hold back on discussing certain aspects of the challenges and weaknesses they faced, but also on particularly successful coping strategies. Similarly, while findings build on educated observations and experiences reported by knowledgeable staff, findings would be strengthened if concrete supporting data had been available. Another limitation of our study is that the investigated firms coped relatively well with challenges caused by the pandemic, where larger volatility might have been expected. It is not unlikely that investigations of firms that either really suffered from the pandemic or ceased new opportunities, could have provided particularly valuable lessons. Analyses in this article are further based on firm experiences in the first year of the pandemic. Our overarching research project on the pandemic's consequences has since continued. Early observations suggest that many of the crisis’ stronger effects took more time to materialize. Examples include supply chain challenges due to shortages of raw materials, intermediate goods, and shipping containers, manifold increases in shipment rates, delays and unpredictable lead times, and increasing driver shortages, both in individual countries (such as the UK and the USA), but also in Europe as a whole. The current pandemic stands out both in terms of its longevity compared to many other crises and the continued intensity of challenges and disruptions throughout. 6.4 Further research Further research could benefit from focusing on challenges and improvements from more medium-to-long term effects and changes, and changes that might become structural, rather than temporary. Examples may include temporary lay-offs becoming permanent or tendencies that are reported of foreign workers having become less interested in working in Norway because of long-term border-crossing challenges, and now filling vacancies in countries closer to home. Also the recent war in Ukraine is observed to cause major new challenges and to reinforce supply chain challenges that started with the pandemic. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Data availability The authors do not have permission to share data. ==== Refs References 1 Nikolopoulos K. Punia S. Schäfers A. Tsinopoulos C Vasilakis C. Forecasting and planning during a pandemic: COVID-19 growth rates, supply chain disruptions, and governmental decisions European Journal of Operational Research 290 1 2021 99 115 32836717 2 Araz O.M. Choi T.M. Olson D.L. Salman F.S. Data Analytics for Operational Risk Management Decision Sciences 51 6 2020 1316 1319 3 Coluccia B. Agnusdei G.P. Miglietta P.P. De Leo F. Effects of COVID-19 on the Italian agri-food supply and value chains Food Control 123 2021 107839 4 Hobbs J.E. Food supply chains during the COVID-19 pandemic Canadian Journal of Agricultural Economics 68 2 2020 171 176 5 Fan Y. Stevenson M. A review of supply chain risk management: definition, theory, and research agenda International Journal of Physical Distribution & Logistics Management 48 3 2018 205 230 6 El Baz J. Ruel S. Can supply chain risk management practices mitigate the disruption impacts on supply chains’ resilience and robustness? Evidence from an empirical survey in a COVID-19 outbreak era’ International Journal of Production Economics 233 2021 107972 7 Pourhejazy P. Kwon O.K. Chang Y-T. Park H. Evaluating Resiliency of Supply Chain Network: A Data Envelopment Analysis Approach Sustainability 9 2 2017 255 8 Ali I. Gölgeci I. Where is supply chain resilience research heading? A systematic and co-occurrence analysis International Journal of Physical Distribution & Logistics Management 49 8 2019 793 815 9 Stone J. Rahimifard S. Resilience in agri-food supply chains: a critical analysis of the literature and synthesis of a novel framework Supply Chain Management 23 3 2018 207 238 10 Kano L. Oh C.H. Global Value Chains in the Post-COVID World: Governance for Reliability Journal of Management Studies 57 8 2020 1773 1777 11 Ivanov D. Predicting the impacts of epidemic outbreaks on global supply chains: A simulation-based analysis on the coronavirus outbreak (COVID-19/SARS-CoV-2) case Transportation Research Part E: Logistics and Transportation Review 136 2020 101922 12 Veselovská L. Supply chain disruptions in the context of early stages of the global COVID-19 outbreak Problems and Perspectives in Management 18 2 2020 490 500 13 Hendricks K.B. Singhal V.R. An Empirical Analysis of the Effect of Supply Chain Disruptions on Long-Run Stock Price Performance and Equity Risk of the Firm Production and Operations Management 14 1 2005 35 52 14 Ellis S.C. Henry R.M. Shockley J. Buyer perceptions of supply disruption risk: A behavioral view and empirical assessment Journal of Operations Management 28 1 2010 34 46 15 Hendricks K.B. Singhal V.R. The effect of supply chain glitches on shareholder wealth Journal of Operations Management 21 5 2003 501 522 16 Béné C. Resilience of local food systems and links to food security – A review of some important concepts in the context of COVID-19 and other shocks Food Security 12 2020 805 822 32837646 17 Dombu S.V. Bardalen A. Strand E. Henriksen B. Lamprinakis L. Norsk matsikkerhet og forsyningsrisiko - Rapport fra arbeidsgruppe i NIBIO NIBIO research report 7 145 2021 18 Ho W. Zheng T. Yildiz H. Talluri S. Supply chain risk management: A literature review International Journal of Production Research 53 16 2015 5031 5069 19 Jüttner U. Supply chain risk management: Understanding the business requirements from a practitioner perspective International Journal of Logistics Management 16 1 2005 120 141 20 Khan O. Burnes B. Risk and supply chain management: Creating a research agenda International Journal of Logistics Management 18 2 2007 197 216 21 Christopher M. Peck H. Building the Resilient Supply Chain International Journal of Logistics Management 15 2 2004 1 14 22 van Hoek R. Research opportunities for a more resilient post-COVID-19 supply chain – closing the gap between research findings and industry practice International Journal of Operations & Production Management 40 4 2020 341 355 23 Zsidisin G.A. Ellram L.M. Carter J.R. Cavinato J.L. An analysis of supply risk assessment techniques International Journal of Physical Distribution & Logistics Management 34 5 2004 397 413 24 Neiger D. Rotaru K. Churilov L. Supply chain risk identification with value-focused process engineering Journal of Operations Management 27 2 2009 154 168 25 Heckmann I. Comes T. Nickel S. A critical review on supply chain risk – Definition, measure and modeling Omega (Oxford) 52 2015 119 132 26 Manuj I. Mentzer J.T. Global supply chain risk management Journal of Business Logistics 29 1 2008 133 155 27 Ponomarov S.Y. Holcomb M.C. Understanding the concept of supply chain resilience International Journal of Logistics Management 20 1 2009 124 143 28 Peck H. Drivers of supply chain vulnerability: an integrated framework International Journal of Physical Distribution & Logistics Management 35 4 2005 210 232 29 Jüttner U. Maklan S. Supply chain resilience in the global financial crisis: an empirical study Supply Chain Management 16 4 2011 246 259 30 Scholten K. Schilder S. The role of collaboration in supply chain resilience Supply Chain Management 20 4 2015 471 484 31 Christopher M. The Agile Supply Chain: Competing in Volatile Markets Industrial Marketing Management 29 1 2000 37 44 32 Pettit T.J. Croxton K.L. Fiksel J. Ensuring Supply Chain Resilience: Development and Implementation of an Assessment Tool Journal of Business Logistics 34 1 2013 46 76 33 Jain V. Kumar S. Soni U. Chandra C. Supply chain resilience: model development and empirical analysis International Journal of Production Research 55 22 2017 6779 6800 34 Liu C.-L. Lee M.-Y. Integration, supply chain resilience, and service performance in third-party logistics providers International Journal of Logistics Management 29 1 2018 5 21 35 Caridi M. Moretto A. Perego A. Tumino A. The benefits of supply chain visibility: A value assessment model Intl. Journal of Production Economics 151 2014 1 19 36 Somapa S. Cools M. Dullaert W. Characterizing supply chain visibility – a literature review International Journal of Logistics Management 29 1 2018 308 339 37 Zhu G. Chou M.C. Tsai C.W. Lessons Learned from the COVID-19 Pandemic Exposing the Shortcomings of Current Supply Chain Operations: A Long-Term Prescriptive Offering Sustainability 12 14 2020 5858 38 Gunessee S. Subramanian N. Ambiguity and its coping mechanisms in supply chains lessons from the Covid-19 pandemic and natural disasters International Journal of Operations & Production Management 40 7–8 2020 1201 1223 39 Vickery S. Calantone R. Dröge C. Supply Chain Flexibility: An Empirical Study Journal of Supply Chain Management 35 2 1999 16 24 40 Mandal S. Sarathy R. Korasiga V.R. Bhattacharya S. Dastidar S.G. Achieving supply chain resilience International Journal of Disaster Resilience in the Built Environment 7 5 2016 544 562 41 Kamalahmadi M. Mellat-Parast M. Developing a resilient supply chain through supplier flexibility and reliability assessment International Journal of Production Research 54 1 2016 302 321 42 Adenso-Diaz B. Mena C. García-Carbajal S. Liechty M. The impact of supply network characteristics on reliability Supply Chain Management 17 3 2012 263 276 43 Wu C. Barnes D. Design of agile supply chains including the trade-off between number of partners and reliability International Journal of Advanced Manufacturing Technology 97 9 2018 3683 3700 44 Toshihiro N. Alexandre B. The Toyota Group and the Aisin Fire MIT Sloan Management Review 40 1 1998 49 45 Goel R.K. Saunoris J.W. Goel S.S. Supply chain performance and economic growth: The impact of COVID-19 disruptions Journal of Policy Modeling 43 2 2021 298 316 46 Chen J. Wang H. Zhong R.Y. A supply chain disruption recovery strategy considering product change under COVID-19 Journal of Manufacturing Systems 60 2021 920 927 33911327 47 Sharma S.K. Bhat A. Risk Mitigation in Automotive Supply Chain: An Empirical Exploration of Enablers to Implement Supply Chain Risk Management Global Business Review 17 4 2016 790 805 48 Dohmen A.E. Merrick J.R.W. Saunders L.W. Stank T.P. Goldsby T.J. When preemptive risk mitigation is insufficient: The effectiveness of continuity and resilience techniques during COVID-19 Production and operations management 2022 Special Issue January 2022 49 Skipper J.B. Hanna J.B. Minimizing supply chain disruption risk through enhanced flexibility International Journal of Physical Distribution & Logistics Management 39 5 2009 404 427 50 Hale T. Moberg C.R. Improving supply chain disaster preparedness: A decision process for secure site location International Journal of Physical Distribution & Logistics Management 35 3 2005 195 207 51 Lopes de Sousa Jabbour A.B. Chiappetta Jabbour C.J. Hingley M. Vilalta-Perdomo E.L. Ramsden G. Twigg D. Sustainability of supply chains in the wake of the coronavirus (COVID-19/SARS-CoV-2) pandemic: Lessons and trends Modern Supply Chain Research and Applications 2 3 2020 117 122 52 Payne C.F. Contingency plan exercises Disaster Prevention and Management 8 2 1999 111 117 53 Fernandes L.J. Saldanha da Gama F. Contingency planning – a literature review Supply Chain Management and Competitiveness 2008 457 467 54 Rimiene K. Bernatonyte D. Supply chain management trends in the context of change Economics & Management 18 3 2013 596 55 Skalli A. Risk attitudes and human mobility during the COVID-19 pandemic Nature Scientific Reports 10 1 2020 19931 56 Pratt J.W. Risk Aversion in the Small and in the Large Econometrica 32 1/2 1964 122 57 Kamilaris A. Fonts A. Prenafeta-Boldύ F.X. The rise of blockchain technology in agriculture and food supply chains Trends in Food Science & Technology 91 2019 640 652 58 Dabbene F. Gay P. Sacco N. Optimisation of fresh-food supply chains in uncertain environments, Part I: Background and methodology Biosystems Engineering 99 3 2008 348 359 59 Yu M. Nagurney A. Competitive food supply chain networks with application to fresh produce European Journal of Operational Research 224 2 2013 273 282 60 Aung M.M. Chang Y.S. Temperature management for the quality assurance of a perishable food supply chain Food Control 40 2014 198 207 61 Dellino G. Laudadio T. Mari R. Mastronardi N. Meloni C. A reliable decision support system for fresh food supply chain management International Journal of Production Research 56 4 2018 1458 1485 62 Miles M.B. Huberman A.M. Saldaña J. Qualitative Data Analaysis: A Methods Sourcebook 2014 Sage London 63 Ambrose E. Marshall D. Lynch D. Buyer supplier perspectives on supply chain relationships International Journal of Operations & Production Management 30 12 2010 1269 1290
PMC009xxxxxx/PMC9735055.txt	==== Front J Clin Psychol Med Settings J Clin Psychol Med Settings Journal of Clinical Psychology in Medical Settings 1068-9583 1573-3572 Springer US New York 36462109 9929 10.1007/s10880-022-09929-x Article A Path Toward Equity and Inclusion: Establishing a DEI Committee in a Department of Pediatrics http://orcid.org/0000-0002-4684-4343 Bersted Kyle A. [email protected] Lockhart Kerri M. Yarboi Janet Wilkerson Marylouise K. Voigt Bridget L. Leonard Sherald R. Silvestri Jean M. grid.240684.c 0000 0001 0705 3621 Department of Pediatrics, Rush University Medical Center, 1620 W. Harrison Street, Chicago, IL 60612 USA 3 12 2022 2023 30 2 342355 9 11 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. The Diversity, Equity, and Inclusion (DEI) committee was established in 2017 within the Department of Pediatrics at Rush University Medical Center (RUMC), an academic medical health center located on the near west side of Chicago, IL. Results from climate surveys highlighted the need for increased DEI initiatives within the department, and a renewed national reckoning on racial tensions sparked an additional sense of urgency for system-level change. This paper outlines the initial creation and ongoing efforts of the DEI committee. Information related to the structure of our committee, aims of our work, progress toward identified goals, as well as ongoing barriers is provided. Academic medical health centers are tasked not only with working and training together, but also to care for a diverse group of patients within a larger community. As such, academic medical health centers represent a unique backdrop and opportunity for individual and system-level change. Keywords Diversity Equity Inclusion Academic health center issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcThose who identify as African American/Black, Hispanic/Latino, American Indian/Alaska Native or Native Hawaiian/Pacific Islander have been considered underrepresented in medicine (URiM) by the Association of American Medical Colleges (AAMC) since 2004. Seventeen years later, it is estimated that only 11.3% of Pediatric faculty at academic health centers (AHCs) are considered URiM (Yoo et al., 2021), and among trainees, only 16.5% of residents and 13.5% of fellows are in this category (Montez et al., 2021). Regarding other professionals employed by AHCs, recent data indicates that most medical assistants (48.9%; “Medical assistants,” 2020) and registered nurses (68.4%; “Registered nurses,” 2020) in the United States are White. Importantly, these percentages do not reflect the increasingly diverse patient populations that AHCs typically serve. In Chicago for example, recent census data shows that nearly 81% of its youth are children of color (Loury & Runes, 2021). Physicians (Shanafelt et al., 2015) and other medical staff (Grace & VanHeuvelen, 2019) working in AHCs are at high-risk for burnout, a risk that has been exacerbated by a global pandemic (Morgantini et al., 2020). Employees who hold marginalized identities are at even higher risk, as they face microaggressions (Nfonoyim et al., 2021) and other forms of discrimination (Snyder & Schwartz, 2019) that contribute to hostile work environments. Thus, systemic discrimination permeates through academic medicine in several ways. In addition to its impact on the lack of diversity in medicine, systemic discrimination sustains environments that are not inclusive or equitable for those from marginalized backgrounds who work in AHCs. This contributes to troubling trends in attrition and lack of retention for URiM faculty (Lett et al., 2018), which has been evidenced by the recent exit of several Black physicians from AHCs (Miller, 2021; Blackstock, 2020). Failing to address issues of belonging and equity creates a revolving door of diversity: marginalized and minoritized individuals enter the healthcare organization but soon exit due, in part, to unsupportive environments characterized by an absence of mentorship and sponsors (Beech et al., 2013), barriers to career advancement (Kaplan et al., 2018), as well as the more overt forms of discrimination aforementioned. Thus, many AHCs have failed to understand the implications of bringing healthcare professionals from diverse backgrounds into non-equitable and non-inclusive environments. The jarring collision of an unprecedented global pandemic with a renewed reckoning on racial tensions last summer (Krieger, 2020) led many organizations such as the AAP (American Academy of Pediatrics), AMA (American Medical Association), ACOG (American College of Obstetricians and Gynecologists) and more recently APA (American Psychology Association) to make statements of apology for or acknowledgement of health inequities and medical racism. Simultaneously, many healthcare institutions expanded their current diversity, equity, and inclusion (DEI) initiatives, or developed them, primarily focused on increasing the number of traditionally underrepresented minorities in the organization. While the importance of DEI work cannot be underscored enough, a significant challenge in this work has been that AHCs often primarily direct initiatives at increasing diversity, little on equity, and even less on inclusion (e.g., Rajaguru et al., 2021). According to APA’s Equity, Diversity, and Inclusion framework (“Equity, Diversity, and Inclusion Framework,” 2021), equity is a “an ongoing process of assessing needs, correcting historical inequities, and creating conditions for optimal outcomes by members of all social identity groups” and inclusion is “an environment that offers affirmation, celebration, and appreciation of different approaches, styles, perspectives, and experiences, thus allowing individuals to bring in their whole selves and to demonstrate their strengths and capacity” (p. 12). Across the country, there has been a mounting pressure and exposed need among healthcare institutions to build effective infrastructures for moving DEI initiatives from idea to action to sustained change. Indeed, there is a rapidly growing body of work aimed at identifying and describing the apparent problems (e.g., Rosenkranz et al., 2021); providing suggested frameworks for potential solutions (e.g., Kang & Kaplan, 2019); and demonstrating favorable trends towards improvement (e.g., Nehemiah et al., 2021), particularly as it relates to increasing diversity in the recruitment and retention of students and trainees. In comparison, there has been notably less reporting on specific approaches for building or expanding institutional DEI work in academic healthcare settings despite its perceived value (e.g., Nora, 2021). While comparatively limited, a review of this work reveals several recurring themes, including the importance of assessing the current DEI culture in a given space, developing a stepwise, strategic plan with specific interventions for addressing issues, and identifying specific outcomes to better track progress towards goals. In one example, Pino-Jones et al. (2021) outline a framework for advancing DEI in a new hospital medicine division that focuses on institutional structures (e.g., compensation, recruitment), people, environments, and core mission areas. Similarly, Lingras et al. (2021) describe their step-by-step approach for developing a DEI committee in a single department within a larger AHC. The authors highlight the importance of engagement, collaboration, and shared decision-making among all stakeholders, including from department membership at the grassroots level to promote local change (bottom up) and from leadership to support larger efforts at the systems level (top down). Although these important contributions to the literature have demonstrated growth of the DEI space in academic medicine, we have found that the specific context in which an AHC functions (e.g., geographical location, size, characteristics of the patient population and neighboring communities) paints a unique picture. This picture captures the attributes that contribute to progress and, importantly, the unmet needs that contribute to inertia in advancing diversity, equity, and inclusion. Thus, an effective approach uses thoughtful assessment and careful tailoring of these broad frameworks to deliver on the needs of the communities within, around, and affected by a system holding as much institutional power as an AHC. Overview In this paper, we describe the formation and continued evolution of a DEI committee within the Department of Pediatrics at Rush University Medical Center (RUMC), a large AHC in Chicago, Illinois. Our DEI committee includes an executive board and five subcommittees. We will discuss the unique social and geographic context that motivates this work and the formation of our committee. We will also overview several DEI-related initiatives, including department climate surveys, changes in faculty and residency recruitment, community-building efforts, didactic and training opportunities, as well as changes in policy and procedures aimed at increasing diversity, promoting equity, and building a culture of inclusion in our department. Successful outcomes will be discussed within the context of barriers faced and areas in which continued work is needed. In this way, we hope that our paper can provide a practical guide for others who may be considering how to establish DEI initiatives in their departments. RUMC: Socio-Geographic Context RUMC is a large academic health center located just two miles outside of downtown Chicago in the Near West Side neighborhood, a notable location in a city as diverse yet historically segregated as Chicago (Sandoval, 2011). Directly to the east of RUMC is the affluent central business district commonly known as the Loop. At the same distance directly west of RUMC are the Garfield Park and North Lawndale neighborhoods, both predominantly Black communities affected by poverty and decades of disinvestment (Mumm & Sternberg, 2022). For additional context, consider that recent community data reveals a 14-year life expectancy gap between residents of the Loop and residents of East Garfield Park (82 years and 68 years, respectively), a gap that has been attributed to structural racism and socioeconomic deprivation (Ansell et al., 2021). Also within distance of RUMC are the majority Hispanic/Latino Lower West Side and Humboldt Park neighborhoods, both home to large foreign-born populations. This is the rich racial/ethnic and socioeconomic tapestry of the patient population served at RUMC. Indeed, according to a recent Health Equity Report (2019), 72% of patients presenting to the RUMC emergency department, 49% of inpatient admissions, 56% of patients receiving primary care, and 40% of patients receiving specialty care identified as Black or Hispanic (Ansell et al., 2018). Given its size and location in a major city in the Midwest, RUMC also draws patients from the greater Chicagoland area, neighboring states, as well as international visitors, further diversifying the RUMC patient population not only with regard to race, ethnicity, and socioeconomic status, but also age, language, gender identity, sexual orientation, and religion/spirituality. Trends in demographic data for the RUMC community of students, trainees, faculty and other staff are not as well reported. During the Fall 2021 term, 13% of the enrolled student body at Rush University identified as Hispanic, 12% Asian, and 8% Black/African American. In the same year, only 10% of faculty at the institution identified as Hispanic or Black/African American (“Rush University Report 2019 to 2021,” 2021). RUMC also reports that 46% of residents and fellows and 50% of all employees are from minoritized groups (“Diversity,” 2022). Taken together, these numbers help contextualize the state of DEI-related issues in the RUMC community. RUMC has been active in addressing such concerns (Ansell et al., 2021) from a top-down approach. Importantly, RUMC also recognizes that in order to fully meet the need of our patients and exist in accordance with our hospital’s values, we must encourage and support departments within the larger organization to also power the movement from the bottom up. RUMC Department of Pediatrics: DEI Efforts A diversity and inclusion (D&I) task force was first created by a prior department chair in 2017 (Fig. 1). At that time, two D&I co-chairs were appointed to organize the inaugural department-wide DEI retreat and develop a climate survey. In late 2019/early 2020, following the retirement of one co-chair and the transition of the second co-chair to other academic domains, a new DEI chair was appointed, and an executive board was established. The board was composed of three Black female pediatricians and two White female pediatricians, including the new DEI chair, the outgoing DEI chair (who has remained involved as an advisor in retirement), as well as three department members in leadership roles (department chair, residency program directors). Decisions about various initiatives and goals are discussed and agreed upon by a majority of executive board members. Fig. 1 Timeline of major events and initiatives Like many institutions, for better or worse, our DEI-related efforts received a newfound sense of attention and urgency in response to the murders of George Floyd, Breonna Taylor, and countless other people of color in 2020. In order to increase communication between the DEI committee and the department, encouraging visibility and accountability, a secretary position was also added to the executive board in 2020. This position also ensured that executive board meetings were scheduled and attended by all members on a biweekly to monthly basis, with agendas and minutes documented and distributed before and after each meeting. The secretary position was advertised to the department and filled by a White male pediatric psychologist. The significance of a faculty member with several layers of societal privilege engaging with this work is worth mention. Because DEI work is often led by Black women and other women of color (Rogers & Jayasinghe, 2021), many are leading these efforts while simultaneously navigating issues of being marginalized in their daily lives, experiencing harm due to an incongruence of organizational DEI values and its actions or policies, being asked to facilitate trainings to educate others around painful lived experiences, or mitigating the potential consequences of calling out mistreatment. As such, it is crucial that those in power within organizations use their privilege to promote these efforts and then “step out of the way” for motivated and passionate colleagues from marginalized groups to use their voices, energy, and ideas toward building a more inclusive culture in the workplace (Tulshyan, 2022). Climate Surveys Perceived work climate has been studied extensively across disciplines and has been linked to a myriad of positive outcomes, including job satisfaction, productivity, and retention (Harter et al., 2003). Moreover, recent studies have suggested that for younger generations, workplace culture may be even more important to workplace satisfaction than pay or other benefits (Tulshyan, 2022). For our purposes, a climate survey was essential because employees draw conclusions about their employer’s priorities through their perceptions of work climate (Schneider et al., 1994), and we wanted to better understand the extent to which department members felt diversity, equity, and inclusion were prioritized in Pediatrics. In addition to assessing our culture, these surveys were also meant to identify targets for DEI-related initiatives and change. Upon creation of the executive board, our first identified task was to review prior climate survey data and distribute a revised version later in 2020. The initial climate survey was adapted from the climate survey used at Rush University’s medical school. It was distributed within our department on two occasions in 2017 (n = 101) and in 2019 (n = 99). In addition to demographic information, the climate survey contained a combination of quantitative and qualitative questions and took approximately 15 minutes to complete. Three primary items relevant to the current paper were as follows: (1) I am satisfied with the climate regarding diversity in the department, (2) members of the department create an environment that is conducive to free and open expression of opinions and beliefs, and (3) I feel a sense of belonging as a member of the department. Respondents who selected agree or strongly agree were aggregated and considered to have a generally positive perception. Across both 2017 and 2019 surveys, responses to all three items remained relatively positive and stable, ranging from 75 to 82% of respondents who provided positive opinions. However, an important comparison between the opinions of faculty and staff was not possible due to the manner in which survey demographics were constructed. Additionally, although initial responses were generally positive, it cannot be overlooked that approximately one quarter of respondents reported a neutral to negative opinion of diversity and inclusion. In 2020, several changes were made to our climate survey to support our continued evaluation of department culture. This updated survey was sent to and completed by a larger group of department members (n = 147), including faculty, residents, fellows, nurses, medical assistants, research teams, clinic coordinators, and other administrative staff. Notably, reaching a larger and more diverse group of department members proved crucial in more accurately assessing our climate. While faculty and trainees continued to provide positive responses regarding free and open expression (87%) and a sense of belonging (88%), staff members had less favorable opinions, with only 72% feeling as though the environment was conducive to free and open expression and 71% feeling a sense of belonging in the department. Moreover, while 80% of faculty and trainees reported feeling as though faculty members in the department are sensitive to issues regarding diversity, this was contrasted with only 68% of staff feeling the same. Questions unique to our 2020 survey also revealed that 34% of respondents (n = 50) described experiencing microaggressions, 8% described experiencing discrimination, 7% encountered racism, and 15% described being mistreated more generally in the workplace. When asked if respondents knew someone who experienced any of these forms of harassment at work, reports across categories increased to 49%, 25%, 19%, and 22%, respectively. Despite these alarmingly high numbers, very few respondents described making a report about harassment experienced by themselves or others. When asked to elaborate, several important themes emerged from the qualitative data. These ranged from people feeling unsure how to make a report, doubting that any change would occur, and feeling fearful of being identified or potential retribution. A few employees also reflected that their experiences have been so commonly occurring that it was not until reflecting on them that they realized they were being mistreated. Strategic Plan and Goals In mid-2020, the DEI executive board reviewed data from all three climate surveys as well as department demographic data and came to the following two conclusions. First, it was clear that there were not enough URiM employees in our department. Of our 103 faculty (i.e., MD, DO, PhD, APP) at the time, only 17% were considered URiM and only 7% identified as Black. The percentage of non-faculty department members (e.g., clinic coordinators, medical assistants, nurses, administrative and research staff) considered URiM was higher; however, this group was still minoritized (46%). Overall, only 35% of our 276 department members were considered URiM, a trend consistently observed within other AHCs in the United States (Ajayi et al., 2021). Second, it was clear that we had work to do regarding our departmental climate. In addition to troubling data on microaggressions, a significant proportion of employees, most notably staff, were not feeling heard or included, and denied that the department was a space that was sensitive to diversity issues. Therefore, in 2020 the executive board established the following strategic plan that could both address identified departmental challenges as well as create meaningful programming and policy change to facilitate progression toward the following aims. Related to diversity, the DEI committee pledged to work toward achieving a workforce, faculty, and student body that are reflective of the unique communities, patients, and region we serve. Related to equity, the DEI committee set forth to increase employee’s knowledge of the historical impact of systemic discrimination on people from marginalized backgrounds through various trainings and initiatives so that all department members gain an increased understanding of the importance of treating others equitably, rather than equally. Related to inclusion, the DEI committee aimed to build a culture of excellence that fosters an environment of cultural humility and mutual respect for those who work at RUMC, those whom we care for, those whom we educate, those who benefit from the scientific advances we achieve, and those with whom we interact in our surrounding communities. Subcommittees and Related Initiatives To begin working toward these goals, five subcommittees were formed in 2020 (Fig. 2): (1) the grand rounds/book club subcommittee was tasked with identifying speakers to present DEI-related topics to our department as well as suggesting book ideas for our book club; (2) the faculty recruitment subcommittee’s primary goal was to identify and implement initiatives meant to bring more URiM candidates and employees into the department; and (3) similarly, the residency recruitment subcommittee aimed to increase URiM representation in the pediatric residency program. Of note, our committee has chosen to change our use of the commonly used term ‘URiM’ to ‘URiM/historically excluded (URiM/HE),’ given the latter’s clearer implication that the underrepresentation of certain minoritized groups in medicine has been a direct result of systemic racism and other forms of oppression. Our final two subcommittees included (4) the retreat subcommittee to coordinate logistics related to our annual retreat; and (5) the operationalization subcommittee, who was tasked with spearheading meaningful “next steps” for transformative action and change in our department, such as identifying and addressing inequities in policies and procedures, establishing a reporting system, or improving inclusion through community-building initiatives. Fig. 2 Structure and goals of the DEI Committee Grand Rounds, Book Club, and Communication Since 2017, the DEI committee has hosted five grand rounds per academic year. Previous speakers, historically identified by the department chair or prior D&I chair, have presented on a wide variety of topics, including social determinants of health, implicit and systemic bias in healthcare, sexual harassment in medicine, racial trauma, and caring for transgender patients. Following the creation of subcommittees in 2020, one member of the department volunteered to lead the grand rounds subcommittee by identifying speakers, soliciting ideas from other department members, and coordinating logistics for each presentation. The DEI committee also established a monthly book club in 2019, led by one of our executive board members, that has collectively read over thirty books since its inception. Books range from fiction to nonfiction, often are written by women or people of color, and typically focus on issues related to discrimination. Although small group discussions have been well-received by those who regularly attended, book clubs have historically been less attended than the committee would have hoped (i.e., 5–7 people). To increase attendance, in 2020 we began including podcasts, videos, and other forms of media as well as changed the meeting time to fall during the lunch hour instead of after work. These changes have broadened the scope and impact of this initiative through increased participation, with more than twenty department members attending our most recent Book Club meeting. Grand rounds and book clubs have been occurring virtually since the onset of the COVID-19 pandemic, with minimal impact on attendance or participation for department members and generally greater ease and access for invited speakers. Lastly, to improve communication with the department, the executive board debuted our “DEI Corner” in 2020, a monthly departmental newsletter that summarizes DEI-related events and trainings, provides updates on ongoing initiatives (including Grand Rounds and Book Clubs), offers information on community engagement opportunities, and highlights minority-owned businesses to support in Chicago. The information included each month is reviewed amongst members of the executive board and the residency program manager before being finalized and distributed via e-mail by a resident who volunteered to take this role. Faculty Recruitment To begin addressing our diversity issue at its core, the executive board examined our recruitment process. Regarding faculty positions specifically, since 2019 only 8% of our candidate pool has identified as URiM/HE. Although this number is likely an underestimate given that 56% of candidates did not report race or ethnicity, greatly increasing the number of URiM/HE candidates was identified as a top priority by our department in collaboration with Faculty Recruitment at the hospital level. Given that a more purposeful and targeted search for URiM/HE candidates from the start of the hiring process has been shown to increase diversity in new hires (Bhalla, 2019), open positions are now posted to over 50 different organizations and associations, many of which specifically focus on diversity in medicine (e.g., Minority Nurses Association, Professional Women of Color Network). Open positions are also advertised at conferences and career fairs that center UriM and other historically excluded minorities, including the National Medical Association (NMA), Student National Medical Association (SNMA), Health Professionals Advancing LGBTQ Equality (GLMA), and National Hispanic Medical Association (NHMA) conferences. Collaboration with Faculty Recruitment has aimed to better integrate DEI into our interview process as well. Specifically, it was established that one ‘DEI liaison’ (either an executive board member or faculty recruitment subcommittee member) now participates in every faculty interview. Specific interview questions created by the executive board relate to topics such as how a candidate approaches their work with diverse patients, past experiences in which a project or decision was enhanced by including diverse perspectives, or ways in which the candidate has promoted or added to diversity, equity, or inclusion in previous positions. Candidates may also be asked questions related to their specialty; for example, a neonatologist might be asked to speak to racial disparities in low birth weight and infant mortality. Notably, through collaboration with Faculty Recruitment on this initiative, a DEI liaison position has been formally created as a role to fill in every department at RUMC. By more purposefully centering DEI during the interview process, we can both illustrate our commitment to this work to prospective candidates (Bhalla, 2019) as well as identify and mitigate biases that may have impacted URiM/HE hires in the past (Tulshyan, 2022). Although we are currently focused on faculty interviews, we plan to eventually expand these efforts into interviews for all employee types. Although we can only speak to correlation with recent efforts, we have seen an increase in URiM/HE hires in Pediatrics from 17% in 2019 to 43% of all new faculty hires in 2021. Moreover, from 2020 to 2021, the percentage of Black new staff hires increased from 19 to 25% and the percentage of Hispanic/Latino new hires increased from 26 to 37%. Despite these promising increases, continuing to improve in this area remains a priority of our committee. For example, we realized through collaboration with Faculty Recruitment that we were failing to assess the full impact of our initiatives by not asking candidates for feedback, especially URiM/HE candidates who were not employed by RUMC after being interviewed. To better assess the interview experience and candidates’ perception of Pediatrics and RUMC, Faculty Recruitment is creating a survey to be distributed to all candidates following interviews. Moreover, analysis of attrition data revealed that although our diversity trends are encouraging, the importance of equity and inclusion efforts are crucial to ensure that increased diversity in our department is not only temporarily observed. In 2020, 65% of voluntary and involuntary departures in the department were by URiM/HE employees, and in 2021 this percentage increased to 72%. Residency Recruitment Importantly, we recognize that an interest in pursuing a medical career develops earlier than residency, and unfortunately, minoritized groups are often excluded in efforts aimed at bringing undergraduates to medical school (Freeman et al., 2016). From 2018 to 2021, URiM/HE applicants have ranged from only 13% to 15% of our pediatric resident candidate pool. In response, we created the Building Blocks: Rush Scholars Program, modeled from a similar program that one of our directors participated in as a URiM/HE high school student. This mentorship program focuses on underrepresented minority junior and senior students attending high schools on the neighboring West Side of Chicago who are interested in medicine. The mission of this program is to provide an integrative curriculum of clinical immersion, personalized mentorship, and community service to prepare underrepresented minorities for matriculation into college, graduate education, and medicine. Students engage in monthly hands-on classroom activities taught by medical students and pediatric residents centered on professionalism, resume building, interviewing skills, life as a medical student, and clinical experiences. Students partner with a medical student and physician mentor to aid in the preparation of their college applications. Students also shadow their medical student mentor in the pre-clinical setting as well as their physician mentor in the clinic/hospital. By participating in this cross-generational community service experience, pediatric residents learn through advocacy, and we hope that student participants will eventually matriculate at Rush University. In 2017, we began tracking the number of URiM/HE applicants that we invite, interview, rank, and match for our residency program. This data are used as a surrogate measure of department initiatives to increase diversity. Our curriculum for faculty has evolved over the years and currently, in accordance with the Accreditation Council for Graduate Medical Education (ACGME) guidelines for creating a diverse and inclusive workforce, includes implicit bias and bystander training, formal education regarding holistic applicant review, and guidance for expressing a genuine and authentic commitment to the success of each resident during recruitment (Gonzaga et al., 2020). Since 2020, we have adhered to the ACGME guidelines in addition to blinding interviewers to applicants’ academic metrics so they may focus on the other aspects of the holistic review. We also began sending representatives from our program to annual national recruitment and networking events, including SNMA, the Latino Medical Student Association (LMSA), and the Howard University Residency Fair. In 2019, a panel of URiM/HE graduates from our program traveled back to RUMC to share their experiences during a grand rounds panel titled “Personal Reflections on Navigating Bias and Microaggressions.” The panel was moderated by a skilled facilitator from outside of our department who stimulated reflection and discussion. That year, we also collaborated with program leadership from an East coast psychiatry program who had seen significant success in their match after several years of efforts to increase diversity. Using feedback discussed in our meeting, program leadership developed a plan that included creating additional opportunities for applicants to meet URiM/HE faculty and residents at the end of their interview day as well as during monthly meetups. During these “hang-back sessions,” URiM/HE faculty and residents share their experiences with the applicants about the climate at RUMC, mentorship experiences, and career development. We have continued to hold these sessions virtually during the pandemic, receiving excellent feedback from participants. In 2020, our residents stepped up with the seven other pediatric residency programs in the Chicagoland area, creating a pledge of solidarity with the Black Lives Matter movement. The statement is front and center on our pediatric residency website. Our residents also outlined their DEI goals for the year: to participate in departmental, institutional, and regional DEI committees; to improve the content of DEI curriculum, including creating programming to address bias, microaggressions and mistreatment; and to advocate for equitable policies affecting child health at RUMC while supporting scholarly work and community engagement activities to address health equity. Residents currently sit on our department’s DEI subcommittees as well as the RUMC-wide Housestaff DEI committee. We also created a formal Advocacy Track for residents specifically interested in community involvement and career development. In 2021, additional programming to support all residents was added including a board preparation program, programs to support finding mentors of similar backgrounds, early research mentor pairing, career development counseling, and guidance in professional identity formation (Gonzaga et al., 2020). The residency program also funded networking and mentoring events for URiM/HE faculty and residents, including those who identify as LGBTQ+, to foster inclusion, support, and mentorship. Working closely with the residency program directors, we also added DEI-specific goals to resident rotations focusing on equity, disparities, and how to discuss race and ethnicity as it relates to health outcomes (Blanchard et al., 2022). Although again we can speak only to its correlation with our efforts, URiM/HE applicants invited to interview for our program increased from 20 to 30% from 2019 to 2020. Although this number fell slightly to 27% of invited applicants in 2021, the percentage of URiM/HE applicants who matched with us increased significantly. After only one URiM/HE candidate matched with our program across our 2019 and 2020 classes, 36% (4/11) of residents in our 2021 class are considered URiM/HE. Although we are encouraged by this trend, we remain committed to continuing to increase the number of URiM/HE applicants who are interviewed and ultimately match at RUMC. DEI Retreat Our inaugural half-day DEI retreat took place in 2017 and has been held annually ever since. To maximize participation at our retreats, all outpatient clinic schedules are blocked months in advance and inpatient responsibilities are minimized as much as possible. In October 2020, our retreat took place virtually with approximately 240 participants in attendance, including faculty, trainees, nurses, research assistants, medical assistants, clinic coordinators, and other staff. Compared to prior retreats, overall attendance increased in 2020 due to the flexibility afforded by virtual attendance, a benefit of the change from an in-person format due to the COVID-19 pandemic. However, the effectiveness of aspects of the retreat meant to be more interactive (i.e., breakout rooms) was variable over the virtual platform, especially given that many rooms included participants who had never met previously. Our 2020 retreat included a powerful keynote address by an invited speaker: a Black pediatrician, public health advocate, and scholar who is renowned for her work on the relationship between structural racism, inequity, and health. The retreat also included a facilitated discussion among a panel of invited RUMC leaders involved in DEI work across the system, a dedicated wellness break, as well as small group breakout discussions among participants. The keynote speaker provided thoughtful suggestions in response to some of our department’s most pressing questions, including how organizations can “move past symbolism and make actual change,” and how we as providers and staff can approach discussions of racism and other forms of oppression with our patients. Compared to previous years, the 2020 retreat included an even more purposeful and pointed emphasis on uncomfortable truths and dialogues about systemic racism in medicine. The impact of the 2020 retreat was immediate; in addition to positive qualitative feedback from department members, participation in DEI subcommittees increased from nine to twenty-nine people and included a more diverse group of faculty, trainees, and staff. Thus, the retreat achieved its goal of challenging department members to engage in self-reflection and community building, and for some, to fuel motivation toward action and change. Our 2021 retreat also was conducted virtually and was attended by approximately 200 people. It too included a keynote address, this time by speakers from a regional organization aimed at dismantling systemic racism in large institutions. The retreat also included several breakout groups and dedicated wellness breaks. Operationalization The fifth and final subcommittee, which focused on operationalizing ideas generated within the department into concrete initiatives, experienced significant growth following our 2020 retreat. In response to the results of our 2020 climate survey, one of their first goals was examining the system for reporting microaggressions and other forms of harassment occurring in the work environment. Unlike residents, who have access to a standardized and formalized process for reporting through graduate medical education, no formalized system exists at the department level for faculty or staff. Although a reporting system exists through the Human Resources (HR) department at the hospital level, their approach and system are not well understood by our department members. As such, the operationalization subcommittee formed three subgroups that included education (e.g., how do we ensure that everyone receives appropriate education and knows what to do when a harm has occurred), logistics (e.g., what does our current system look like and how can it be improved?), and consequences (e.g., what happens when harm has occurred?). Conversations with HR are ongoing; however, some progress has been made through efforts to integrate aspects of restorative justice (RJ) into our department. RJ is a community-centered and relational approach that brings together those who have harmed and been harmed that brings accountability and healing to all involved in a meaningful way (DeWolf & Geddes, 2019). At this time, an informal system has been established by the executive board in which, following a report of mistreatment, all involved parties are invited to take part in a RJ-based conversation facilitated by one of our identified RJ facilitators. Although this system is not adequate for all types of reports, we intend to continue utilizing it when appropriate (e.g., microaggression, perceived unfair treatment) and when both parties are open to this type of healing. Although examining RJ as a philosophical framework is outside the scope of this paper, one primary component that we are also beginning to implement is the community-building circle. These circles are designed to build connection and address conflicts that disrupt a group’s ability to function as a community; through facilitation by a trained circle-keeper, RJ circles allow for safe, inclusive spaces that foster personal connections and center on humanistic values (Behel, 2019). Although most often utilized in criminal justice settings, RJ practices are more recently being implemented in healthcare settings (Long et al., 2022). Thus far, our residents have taken part in RJ circles, both during their orientation as well as intermittently throughout their training, and this year we had opportunities for division chiefs to participate as well. To further integrate this approach into our department, our next DEI retreat in 2022 will purposefully broaden the scope of the RJ framework by inviting all department members to participate in RJ circles. Specifically, we plan to create 14 circles based on job description and clinic location that will each meet with a RJ facilitator during our retreat as well as periodically throughout the year. Initially, circle prompts will focus solely on strengthening interpersonal connections; however, we hope that future circles can also address harms when they have occurred and promote healing among colleagues, therefore improving retention as well. Changes in hospital policy have also been achieved through the operationalization subcommittee. In response to an incident in which a patient’s parent used racist language toward a Black pediatrician, we initiated dialogues with clinical and HR leaders, Patient Relations, and RUMC’s legal team to enact policy change. As a result of these conversations and ongoing advocacy, RUMC’s patient rights and responsibilities policy was updated to better protect and advocate for all RUMC employees who are victims of racist language and actions in the workplace. Knowing how important visibility is to DEI-related issues (Bourke & Titus, 2019), our policy now more explicitly refers to discrimination based on age, race, ethnicity, ancestry, marital or parental status, veteran’s status, religion, culture, language, disability, sex, sexual orientation, gender, gender identity/expression, socioeconomic status or any other category protected by federal/state law or country/city ordinance as behavior that is not tolerated. Another initiative identified by the operationalization committee and executive board was improving the availability of resources (e.g., compensation, protected time) for DEI-related efforts, as these speak volumes about an organization’s commitment to DEI. As Singleton et al. (2021) recently noted, “by providing these resources in a top-down manner, it signifies that the voices of historically excluded scholars are not just heard but valued and essential to creating a productive and collaborative community” (p. 3366). Our department chair has successfully advocated for access to funds that allow our department to host nationally renowned speakers and provide relevant training during our DEI retreats. In terms of retention, our department recently participated in an analysis and adjustment of faculty compensation to better reflect national benchmarks as well as to eliminate any identified pay disparities among faculty. Medical assistants across RUMC were also offered a retention bonus. Our efforts also focused on securing protected time given the myriad costs of DEI work on those who are asked to carry it out, especially employees of color. This is not only true at RUMC; research shows that UriM/HE faculty generally have greater clinical responsibilities and are more active in diversity efforts than non-UriM/HE faculty (Campbell, 2013; Palepu et al., 2000). This is one of several factors contributing to the ‘minority tax’ in academic medicine, defined as “the tax of extra responsibilities placed on minority faculty in the name of efforts to achieve diversity,” which “impact their recruitment, advancement, and retention” (Campbell, 2021; Rodríguez et al., 2015, Campbell & Pololi, 2015). After dedicating 0.1 FTE (full-time equivalent) to the chair of our DEI committee in 2020, Pediatrics was the first department at RUMC to offer dedicated effort to support a department DEI chairperson through the chair’s endowment fund, followed more recently by the Department of Obstetrics and Gynecology (OB-GYN). In collaboration with other departments, our committee has asked hospital leadership for a dedicated DEI chairperson for every department at RUMC, and the interim dean is advocating for this to be departmentally funded in the future. In this way, DEI work can be created and salaried as a priority that is recognized as a contribution towards advancement, rather than as a supplemental experience that employees put uncompensated time and effort toward, often at the expense of their primary academic and clinical roles or personal lives. Establishing department DEI chairpersons across RUMC also encourages collaborations among departments and promotes ongoing learning and improvement, another important aspect of DEI work in AHCs. Partnerships across sections, divisions, and teams represent a meaningful way to make connections, share ideas, and improve the culture of the AHC system at large. Our DEI committee has made efforts to not only connect with others outside our department about DEI-related initiatives, but to lead by example with our own efforts for others to follow. We have presented our efforts to other departments as well as to RUMC’s Racial Justice Action Committee (RJAC), a hospital-level group whose mission is to advance social and racial justice along with health equity at RUMC. We also have partnered with The Rush Center for Gender, Sexuality and Reproductive Health (AFFIRM), an organization that works to provide safe, comprehensive, and affirming care to LGBTQ+ patients and employees at Rush. More recently, our committee connected with physicians in Surgery and Psychiatry to better coordinate similar efforts around creating a faculty reporting system at the hospital level. We remain committed to meaningful partnerships across RUMC that promote equity and inclusion for all employees, as well as the patients that we serve. 2021 Check-in Survey In response to departmental feedback following our 2020 retreat (i.e., comments made during the retreat to the secretary; comments made in the climate survey), the executive board implemented a new biennial climate check-in survey to more efficiently “check the pulse” of the department. Compared to the climate survey, the check-in survey was shorter (5–10 min to complete), easier to analyze (related questions eliminated or combined), and more specific and purposeful in its approach. Additionally, this survey was intended to better capture participation in DEI events, as well as provide an opportunity for department members to anonymously voice their opinions of the various initiatives put forth by the executive board and subcommittees since the 2020 retreat. A few positive findings from the inaugural check-in survey included that 76% of respondents agreed that diversity, equity, and inclusion is moving in the right direction in the department and 81% of respondents agreed that the department is a safe and welcoming space for employees and families. A smaller majority, 62% of respondents, described feeling listened to by department/DEI leadership, and 43% of respondents indicated that they had been more engaged with DEI initiatives compared to the past. Qualitatively, some respondents reported that increased efforts by the DEI committee have made it easier to bring up related concerns and have more open dialogues in the department. Many respondents commented feeling grateful that DEI efforts became “more visible” in response to the events of 2020. Others described feeling inspired by grand rounds speakers and having learned a great deal through participation in book clubs and our retreat. However, several concerning findings emerged from the data as well. First, although the number of respondents (n = 100) was commensurate with participation in the 2017 and 2019 surveys, it was a notable decrease from 2020 and represented a response rate of only 33%. For those who did complete this survey, the majority (62%) were faculty or trainees, meaning that the group who was most critical of the department climate in 2020 (i.e., staff) was largely missed. Although 25% of respondents reported having taken an active role in DEI efforts by volunteering as a subcommittee member, regular participation in DEI-related grand rounds (35%) and book club (11%) was extremely low. When asked to indicate their attendance more specifically for 14 DEI-related events over the past academic year, book club attendance (seven total meetings) ranged from 2 to 20% of respondents and grand rounds attendance (five presentations) ranged from 24 to 35%. Most notably, nearly half (48%) of respondents reported that they regularly have “no DEI involvement.” When asked to elaborate on what barriers prevented more frequent involvement, several administrative and logistical challenges were identified, including lack of time, scheduling conflicts, and feeling overburdened by their primary work responsibilities (e.g., clinical time, documentation, staffing issues, other meetings). However, beyond these types of challenges, some respondents also described negative feelings (e.g., feeling alienated by the department) or philosophical differences (e.g., describing DEI initiatives as hostile) that led to a more intentional disengagement with the DEI curriculum. This begs these questions for leadership: which types of barriers are most easily changed in the short-term via allocation of additional resources, and how do we overcome barriers related to the attitudes and beliefs of those who do not buy-in to the benefits of this work in the long-term? Concerning trends also emerge when looking closer at the department culture data. In response to the question regarding DEI moving in the right direction in the department, 8% disagreed and 16% described feeling neutral. In addition to addressing those who disagreed, more critically analyzing the ambivalence of the 16% is crucial. Do these respondents feel indifferent because they lack awareness of the prevalence and impact of institutional oppression in the department and in medicine more generally? Or are they aware yet burnt out, feeling helpless or lacking faith in leadership’s ability to enact real change? A comment from a subcommittee member raises this exact issue, as they noted that putting in hours of work related to identifying an adequate reporting system without seeing tangible change “takes the wind out of our sails.” Similar questions arise during analysis of the remaining questions. Twelve percent of respondents disagreed when asked if they feel listened to by department leadership, and another 26% of respondents described feeling neutral about this. Also requiring attention are the additional 14% of those who replied neutrally when asked if the department is a safe and welcoming space. Of course, burnout, fatigue, or perceptions that there has been a lack of meaningful change in the past may be to blame. However, it is also possible that these department members are afforded the privilege of not needing to speak with leadership about DEI-related matters or needing to consider whether they feel safe or welcomed at work. Regardless of their cause, these findings represent a direct challenge to leadership to continue to work toward meaningful change through initiatives focused on equity and inclusion. Conclusion and Future Directions Our DEI committee was established with the aim of improving diversity in the Department of Pediatrics while simultaneously improving our culture to become more equitable and inclusive. We have made progress over the past several years but recognize that the work must continue. Although we have observed significant increases in URiM/HE new hires, faculty and staff members who identify as URiM/HE remain minoritized in our department and comprise a disproportionate majority of our attrition. Our residency recruitment subcommittee has successfully integrated several DEI initiatives into our program; however, our metrics remain lower than our targets. Although we are proud of the range and depth of educational opportunities we provide through grand rounds, book clubs, and retreats, barriers to greater departmental participation remain. While our operationalization subcommittee has been successful in changing some policies and fostering collaboration, our reporting system is a work in progress and our RJ work is in its infancy. Our climate surveys have shed light on several positive aspects of our department yet has also highlighted several ongoing barriers to DEI work, harassment and discrimination experienced by URiM/HE department members, as well as a difference in opinion across department members related to DEI efforts and their perceived importance. Although difficult work remains, we believe it is important to highlight that engaged leadership has been a primary reason for the successes we have experienced. As outlined, the chair of Pediatrics sits on our DEI executive board and has made clear that DEI initiatives are a priority through (1) creative, economical, and flexible use of funds and (2) positive relationships with hospital finance and leadership. Through actions such as using the chair’s endowment money to fund speakers and trainings, planning months in advance to block schedules for the retreat, meeting with various administrators and leaders throughout the AHC to build the case for DEI-related resources, and advocating for protected FTE time, hospital leadership has received the message that this work is important to our department. Importantly, RUMC as a system embraces DEI efforts, which we know may not be the case at all institutions. In addition to frequently corresponding with employees about DEI-related current events and opportunities to celebrate diversity (i.e., Pride, Black History month), RUMC recently established the RUSH BMO Institute for Health Equity, an institution focused on funding education and training programs, school-based health centers, and community outreach and research initiatives meant to address health inequities. Unfortunately, the systemic issues reviewed here do not only negatively impact our departmental climate; they also negatively impact the patients and communities that AHCs serve. A stark example of this was discussed in a recent study which found that racial concordance between Black infants and their physicians cuts infant mortality in half, especially in complicated cases as well as in hospitals that treat more Black infants (Greenwood et al., 2020). This is especially relevant for RUMC, given that its primary service area includes several predominantly Black neighborhoods and that our state-of-the art neonatal intensive care unit treats many medically complex children. Despite these realities, as previously mentioned, less than 10% of our Pediatric faculty members currently identify as Black. Although only one example of many, this disparity highlights the urgent need for a continued emphasis on DEI initiatives in AHCs. We have an obligation to ensure equitable healthcare is available for all who seek out our institutions. Our findings demonstrate how vitally important it is for DEI initiatives to extend beyond recruiting people with diverse identities into our institutions to place equal, if not greater, emphasis on creating an inclusive culture that will cultivate success and a desire to stay in the RUMC community for those who work here. AHCs with successful DEI initiatives develop comprehensive strategies that are driven by institutional leadership; they are inclusive and centering of the most marginalized voices and, most importantly, they are transformative. As an anchor, commitment to these initiatives should include cluster hires (Valantine, 2020), dedicated budgets, autonomy, consideration for leadership roles, pathways for advancement for URiM/HE employees, and sufficient compensated FTE for DEI-related roles. However, initiatives providing only these basic supports are unlikely to produce meaningful and sustained changes to institutional culture. A commitment to doing this work is, categorically, a commitment to changing the institutional structures from the inside out, as this work cannot effectively occur in the absence of substantive change. Several AHCs, including RUMC, were recently featured in a piece highlighting successful strategies to confront racism in healthcare by centering equity as a foundation (Hostetter & Klein, 2021). These strategies included the invaluable role of metrics as a tool in this work, engaged leadership, the need for safety and anonymity in reporting systems, and accountability for those engaging in harmful behaviors or failing to participate in DEI initiatives. For example, at Penn State, a digital platform is being piloted that allows employees to report racism anonymously and in real time. In its first two weeks of use, nine reports were generated using the program with 15 people reporting from a single department. At UCLA, an equity dashboard monitors a variety of metrics, including racial and other differences across hiring, promotion, training, contracting, patient and employee grievances, and vendors providing goods and services, and is reviewed by an equity council monthly. This work requires tremendous courage. It requires pulling back the veneer and examining the source of deeply entrenched structural oppression and inequity. This is necessary work for healthcare institutions that endeavor to be equitable in their care delivery because it starts with equity inside the institution. It is not enough to declare our DEI values in mission statements. We must also demonstrate our commitment with actions that reflect these values. This means actively dismantling current harmful structures, and reimagining and rebuilding a health system that values those marginalized based on race or gender, those with disabilities, those who prefer care in a language other than English, and all other variations of marginalization that occur in our health system. This can be accomplished, but it will certainly mean making uncomfortable choices: choices about redistribution of resources, money, and power to be more just and equitable. It will require rebuilding our healthcare system to decentralize experiences and ideas that advance dominant culture so that marginalized groups are appropriately represented, evaluated, and cared for in our hands. Funding Not applicable. Data Availability Not applicable. Code Availability Not applicable. Declarations Conflict of interest Kyle A. Bersted, Kerri M. Lockhart, Janet Yarboi, Marylouise K. Wilkerson, Bridget L. Voigt, Sherald R. Leonard and Jean M. Silvestri declare that they have no conflict of interest. Ethical Approval Not applicable. Consent to Participate Not applicable. Consent for Publication Not applicable. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Change history 1/19/2023 A Correction to this paper has been published: 10.1007/s10880-023-09939-3 ==== Refs References Ajayi AA Rodriguez F de Jesus PV Prioritizing equity and diversity in academic medicine faculty recruitment and retention JAMA Health Forum. 2021 2 e212426 10.1001/jamahealthforum.2021.2426.PMID:36218655;PMCID:PMC9552628 36218655 American Psychological Association equity, diversity, and inclusion framework. (2021, April). https://www.apa.org/about/apa/equity-diversity-inclusion/equity-division-inclusion-framework.pdf Ansell DA Oliver-Hightower D Goodman LJ Lateef OB Johnson TJ Health equity as a system strategy: The Rush university medical center framework NEJM Catalyst 2021 10.1056/cat.20.0674 Beech BM Calles-Escandon J Hairston KG Langdon SE Latham-Sadler BA Bell RA Mentoring programs for underrepresented minority faculty in academic medical centers Academic Medicine 2013 88 541 549 10.1097/acm.0b013e31828589e3 23425989 Behel, J. (2019, November 12). I Shall Be Released.” Restorative justice techniques can address healthcare burnout & attrition. Reflective MedEd. https://reflectivemeded.org/2019/11/ Bhalla N Strategies to improve equity in faculty hiring Molecular Biology of the Cell 2019 30 2744 2749 10.1091/mbc.e19-08-0476 31609672 Blackstock, U. (2020). Why black doctors like me are leaving faculty positions in academic medical centers. STAT. https://www.statnews.com/2020/01/16/black-doctors-leaving-faculty-positions-academic-medical-centers/ Blanchard AK Blanchard JC Suah A Dade A Burnett A McDade W Reflect and reset: Black academic voices call the graduate medical education community to action Academic Medicine 2022 97 967 972 10.1097/acm.0000000000004664 35294401 Bourke, J., & Titus, A. (2019). Why inclusive leaders are good for organizations, and how to become one. Harvard Business Review. https://hbr.org/2019/03/why-inclusive-leaders-are-good-for-organizations-and-how-to-become-one Campbell KM A letter to the editor: Under-represented minority faculty in academic medical centers Journal of Health Care for the Poor and Underserved 2013 24 viii ix 10.1353/hpu.2013.0011 23377744 Campbell KM The diversity efforts disparity in academic medicine International Journal of Environmental Research and Public Health 2021 18 4529 10.3390/ijerph18094529 33923280 del Pino-Jones A Cervantes L Flores S Jones CD Keach J Ngov LK Schwartz DA Wierman M Anstett T Bowden K Keniston A Burden M Advancing diversity, equity, and inclusion in hospital medicine Journal of Hospital Medicine 2021 10.12788/jhm.3574 33617435 DeWolf TN Geddes J The Little Book of Racial Healing: Coming to the Table for Truth-Telling, Liberation, and Transformation (Justice and Peacebuilding) 2019 Illustrated Brattleboro Good Books Diversity\|Rush University System for Health. (2022). Rush Diversity. https://www.joinrush.org/Diversity/ Freeman BK Landry A Trevino R Grande D Shea JA Understanding the leaky pipeline Academic Medicine 2016 91 987 993 10.1097/acm.0000000000001020 26650673 Gonzaga AMR Appiah-Pippim J Onumah CM Yialamas MA A framework for inclusive graduate medical education recruitment strategies Academic Medicine 2020 95 710 716 10.1097/acm.0000000000003073 31702694 Grace MK VanHeuvelen JS Occupational variation in burnout among medical staff: Evidence for the stress of higher status Social Science & Medicine 2019 232 199 208 10.1016/j.socscimed.2019.05.007 31102930 Greenwood BN Hardeman RR Huang L Sojourner A Physician–patient racial concordance and disparities in birthing mortality for newborns Proceedings of the National Academy of Sciences 2020 117 21194 21200 10.1073/pnas.1913405117 Harter JK Schmidt FL Keyes CLM Well-being in the workplace and its relationship to business outcomes: A review of the Gallup studies Flourishing: Positive Psychology and the Life Well-Lived 2003 Washington American Psychological Association 205 224 Hostetter, M., & Klein, S. (2021, October 18). Confronting racism in health care. The Commonwealth Fund. https://www.commonwealthfund.org/publications/2021/oct/confronting-racism-health-care Kang SK Kaplan S Working toward gender diversity and inclusion in medicine: Myths and solutions The Lancet 2019 393 579 586 10.1016/s0140-6736(18)33138-6 Kaplan SE Raj A Carr PL Terrin N Breeze JL Freund KM Race/ethnicity and success in academic medicine Academic Medicine 2018 93 616 622 10.1097/acm.0000000000001968 29068820 Krieger N ENOUGH: COVID-19, structural racism, police brutality, plutocracy, climate change—and time for health justice, democratic governance, and an equitable, sustainable future American Journal of Public Health 2020 110 1620 1623 10.2105/ajph.2020.305886 32816556 Lett E Orji WU Sebro R Declining racial and ethnic representation in clinical academic medicine: A longitudinal study of 16 US medical specialties PLoS ONE 2018 13 e0207274 10.1371/journal.pone.0207274 30444928 Lingras KA Alexander ME Vrieze DM Diversity, equity, and inclusion efforts at a departmental level: building a committee as a vehicle for advancing progress Journal of Clinical Psychology in Medical Settings 2021 10.1007/s10880-021-09809-w 34529234 Long R Cleveland Manchanda EC Dekker AM Kraynov L Willson S Flores P Samuels EA Rhodes K Community engagement via restorative justice to build equity-oriented crisis standards of care Journal of the National Medical Association 2022 10.1016/j.jnma.2022.02.010 35365355 Loury, A., & Runes, C. (2021, August 20). Takeaways from 2020 census data for Chicago and Illinois in 6 graphics. WBEZ Chicago. https://www.wbez.org/stories/census-2020-data-in-graphics-for-chicago-and-illinois/ad8d66cb-7982-4b15-b7bf-a32ffcc724b7 Medical assistants. (2020). Data USA. https://datausa.io/profile/soc/medical-assistants Miller, P., MD. (2021, April 9). Op-Ed: The irony of DEI during the fall of black doctors. MedPage today. https://www.medpagetoday.com/publichealthpolicy/generalprofessionalissues/92016 Montez K Omoruyi EA McNeal-Trice K Mack WJ Yemane L Darden AR Russell CJ Trends in race/ethnicity of pediatric residents and fellows: 2007–2019 Pediatrics 2021 10.1542/peds.2020-026666 34470896 Morgantini LA Naha U Wang H Francavilla S Acar M Flores JM Crivellaro S Moreira D Abern M Eklund M Vigneswaran HT Weine SM Factors contributing to healthcare professional burnout during the COVID-19 pandemic: A rapid turnaround global survey PLoS ONE 2020 15 e0238217 10.1371/journal.pone.0238217 32881887 Mumm J Sternberg C Mapping racial capital: Gentrification, race and value in three Chicago neighborhoods Urban Affairs Review 2022 10.1177/10780874221082614 Nehemiah A Roberts SE Song Y Kelz RR Butler PD Morris JB Aarons CB Looking beyond the numbers: Increasing diversity and inclusion through holistic review in general surgery recruitment Journal of Surgical Education 2021 78 763 769 10.1016/j.jsurg.2020.08.048 32950431 Nfonoyim B Martin A Ellison A Wright JL Johnson TJ Experiences of underrepresented faculty in pediatric emergency medicine Academic Emergency Medicine 2021 28 982 992 10.1111/acem.14191 33289950 Nora LM Using accreditation to transform diversity, equity, and inclusion efforts into diversity, equity, and inclusion systems Academic Medicine 2021 97 25 29 10.1097/acm.0000000000004377 Palepu A Carr PL Friedman RH Ash AS Moskowitz MA Specialty choices, compensation, and career satisfaction of underrepresented minority faculty in academic medicine Academic Medicine 2000 75 157 160 10.1097/00001888-200002000-00014 10693848 Rajaguru PP Ademuwagun L Reddy NG Pierre-Louis Y Moreira CC Moving beyond diversity: A scoping review of inclusion initiatives in the surgical workforce Journal of the American College of Surgeons 2021 233 S228 10.1016/j.jamcollsurg.2021.07.470 Registered nurses. (2020). Data USA. https://datausa.io/profile/soc/registered-nurses Rodríguez JE Campbell KM Pololi LH Addressing disparities in academic medicine: What of the minority tax? BMC Medical Education 2015 10.1186/s12909-015-0290-9 25638211 Rogers, A. J., & Jayasinghe, T. (2021). The hidden cost of DEI work—And what to do about it. Non Profit News\|Nonprofit Quarterly. https://nonprofitquarterly.org/the-hidden-cost-of-dei-work-and-what-to-do-about-it/ Rosenkranz KM Arora TK Termuhlen PM Stain SC Misra S Dent D Nfonsam V Diversity, equity and inclusion in medicine: Why it matters and how do we achieve it? Journal of Surgical Education 2021 78 1058 1065 10.1016/j.jsurg.2020.11.013 33279427 Rush University Medical Center. (2019, March). 2018 Health equity report: Patient care through an equity lens. https://healthequitychicago.org/wp-content/uploads/2019/08/2018-Health-Equity-Report.pdf Rush university report 2019 to 2021. (n.d.). https://www.rushu.rush.edu/sites/default/files/_Rush%20PDFs%20and%20Files/ru-three-year-report-2019-2021.pdf Sandoval JSO Neighborhood diversity and segregation in the Chicago metropolitan region, 1980–2000 Urban Geography 2011 32 609 640 10.2747/0272-3638.32.5.609 Schneider B Gunnarson SK Niles-Jolly K Creating the climate and culture of success Organizational Dynamics 1994 23 17 29 10.1016/0090-2616(94)90085-x Shanafelt TD Hasan O Dyrbye LN Sinsky C Satele D Sloan J West CP Changes in burnout and satisfaction with work-life balance in physicians and the general US working population between 2011 and 2014 Mayo Clinic Proceedings 2015 90 1600 1613 10.1016/j.mayocp.2015.08.023 26653297 Singleton KS Murray DSR Dukes AJ Richardson LN A year in review: Are diversity, equity, and inclusion initiatives fixing systemic barriers? Neuron 2021 109 3365 3367 10.1016/j.neuron.2021.07.014 34358432 Snyder CR Schwartz MR Experiences of workplace racial discrimination among people of color in healthcare professions Journal of Cultural Diversity 2019 26 96 107 Tulshyan R Oluo I Inclusion on purpose: An intersectional approach to creating a culture of belonging at work 2022 Cambridge The MIT Press Valantine HA NIH’s scientific approach to inclusive excellence The FASEB Journal 2020 34 13085 13090 10.1096/fj.202001937 33373164 Yoo A George BP Auinger P Strawderman E Paul DA Representation of women and underrepresented groups in US academic medicine by specialty JAMA Network Open 2021 4 e2123512 10.1001/jamanetworkopen.2021.23512 34459909
PMC009xxxxxx/PMC9743133.txt	==== Front Eur Phys J Spec Top Eur Phys J Spec Top The European Physical Journal. Special Topics 1951-6355 1951-6401 Springer Berlin Heidelberg Berlin/Heidelberg 36532608 727 10.1140/epjs/s11734-022-00727-y Review Paper based microfluidic devices: a review of fabrication techniques and applications Anushka http://orcid.org/0000-0003-3371-7879 Bandopadhyay Aditya [email protected] Das Prasanta Kumar [email protected] grid.429017.9 0000 0001 0153 2859 Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302 India 12 12 2022 2023 232 6 781815 23 8 2022 9 11 2022 © The Author(s), under exclusive licence to EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. A wide range of applications are possible with paper-based analytical devices, which are low priced, easy to fabricate and operate, and require no specialized equipment. Paper-based microfluidics offers the design of miniaturized POC devices to be applied in the health, environment, food, and energy sector employing the ASSURED (Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment free and Deliverable to end users) principle of WHO. Therefore, this field is growing very rapidly and ample research is being done. This review focuses on fabrication and detection techniques reported to date. Additionally, this review emphasises on the application of this technology in the area of medical diagnosis, energy generation, environmental monitoring, and food quality control. This review also presents the theoretical analysis of fluid flow in porous media for the efficient handling and control of fluids. The limitations of PAD have also been discussed with an emphasis to concern on the transformation of such devices from laboratory to the consumer. issue-copyright-statement© EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction In microfluidics, fluids and particles are controlled and manipulated by precise equipment on scales of tens to hundreds of micrometers. Microfluidics leverages fluids in microchannels to exploit their most obvious characteristics small size and laminar flow. Microfluidics is also used for medical and chemical applications, such as lab-on-a-chips (LOC) and micro total analysis systems (μTAS). This technology features superior advantages over conventional macro-scale platforms (e.g. centrifuges, flow cytometers, etc.) because it can precisely control and manipulate biological particles and the surrounding microenvironment. Although microfluidics has been developing rapidly, the progression of POC microfluidic systems still faces various barriers like sample processing, chip to real-world connection, sensing, and miniaturization or abolition of additional fluid control elements. The difficulty and high expenses of advancement of microfluidic products, make it difficult to reach end customers. Therefore, Martinez et al. [1] merged the concept of microfluidics with paper, as paper meets the optimal base material parameters for the transfer of these devices from the lab to consumers. These paper-based analytical devices (PADs) offer a seperate site for liquid transportation via capillary forces without the use of additional pumps. Paper-based microfluidics is a rapidly growing field that has attracted significant attention due to its advantages over traditional microfluidics, such as low manufacturing costs, accessibility, ease of operation, scalability, fast response, POC diagnostics, and little solution usage. Therefore, this technology meets the guidelines of WHO for an ideal POC diagnostic system. Under WHO guidelines, the diagnostic test/device must meet the ASSURED requirements (as shown in Fig. 1) which include being (i) affordable, (ii) sensitive, (iii) specific, (iv) user-friendly, (v) rapid and robust, (vi) equipment-free, and (vii) deliverable to end-users for the selection of diagnostics [2, 3].Fig. 1 An illustration of the WHO’s ASSURED criteria for diagnostics As a result, the field of testing is constantly developing and discovering new tools for identifying both infectious and non-infectious disorders. Incorporating microfluidics and biosensing principles can meet the criteria listed by the WHO here for choosing testing tools [3, 4]. In addition to satisfying the ASSURED criteria, microfluidic chip biosensors provide many additional advantages, such as portability, the need for fewer samples, the possibility of installation in rural parts, reduced energy consumption, less errors, numerous biomarker identification, etc. Creating channels is all that is necessary to execute multiplexed analysis by a succession of hydrophilic-hydrophobic microstructures on paper substrates to create PADs. Photolithography, wax printing, screen printing, inkjet printing, and plasma oxidation are some of the common methods to create channels in the device. To improve the sensitivity and working of the device, certain modifications like the incorporation of the electrode were required. Colorimetric, chemiluminescence, and electrochemical techniques are employed for the goal of detection, and they entail the measurement of color intensity created on the PAD. Figure 2 shows a typical configuration for a paper-based microfluidic analytical device in which patterns were created on a simple Whatman filter paper to create the hydrophobic-hydrophilic contrast and then reagents and samples have been loaded to analyze the developed color in the reaction zone. There are many detection techniques have been explored including colorimetric analysis, fluorescent analysis, electrochemical analysis, etc. Colorimetric detection is a good method for μPADs, which has the benefits of visual monitoring, quick sensing, practicality for rural applications, ease of use, and greater stability. In spite of improvements, there are still a few problems with paper-based microfluidic technology. The issues to take into account relate to the devices’ stability and shelf life, particularly those that involve biological tests for analysis. The field of ‘PADs’ has experienced tremendous growth, but there are still many obstacles to overcome and possibilities to seize. The development of tools that are simpler to use must also continue. The complexity of assays for current technologies can be limited because of their intrinsic simplicity, or they can do complicated activities but are difficult to operate. This review explains the design and fabrication methods with various adjustments to generate practical assay with efficient handling and regulation of fluids, since μPADs primary issue is the paucity of flow control, this slows down the process from the lab to the public hands and creates marketing challenges. Then it will transition to how these technologies carry out detection. The quantitative understanding of capillary flow was also revealed with various theoretical analysis of fluid flow in porous media. The Review will conclude with applications of PAD technology across medical diagnosis, environmental monitoring, energy generation, and food safety monitoring before concluding with a consideration of future directions of paper-based devices.Fig. 2 PAD a filter paper, b patterned hydrophobic channels, c loading reagents, d loading sample, and e result Fabrication Like any other microfluidic system, fabrication is very important also for paper based device. The remarkable characteristics of paper have been the key to the development of PADs. There is no need to use external energy devices with paper-based microfluidics since it relies on capillary action to transfer liquids. Two basic steps are involved in creating μPADs: Paper patterning and device customization to serve the purposes for which they are intended. Patterning Patterning is the first step in the fabrication of any PAD and is required to achieve hydrophilic-hydrophobic contrast in a porous paper. The two main patterning techniques for creating microfluidic channels on paper substrates are mechanical cutting and hydrophobic material treatment. Direct and indirect methods can be used to further categorize the second technique into two categories. In the direct technique, the hydrophobic material is applied directly to the paper, although for the indirect methods, the hydrophobic material is applied selectively at different stages using a mask, as indicated in Fig. 3. Wax printing, inkjet printing, flexographic printing, and laser cutting are examples of direct techniques while indirect method involves Plasma etching, photolithography, laser treatment, etc. The strategies of patterning principles can be separated based on the binding states of the hydrophobic agent: (1) physically sealing the pores of the paper, (2) physically depositing a hydrophobizing substance on the cellulose fiber surfaces, and (3) chemically altering the surfaces of the fibers.Fig. 3 Classification of patterning methods to form microfluidic channels. Patterning is classified based on the technique of transferring hydrophobic material on paper. If the hydrophobic material is applied directly to the hydrophilic paper substrate, it is called the direct method while if the hydrophobic material is applied selectively at different stages, it is the indirect method Photolithography Photolithography was used to create the first paper-based microfluidic devices, and it continues to be preferable due to its accuracy and high resolution [5]. The photolithography begins by covering the complete paper with a negative photoresist as shown in Fig. 4. Moreover, the photoresist is crosslinked in the appropriate pattern by using a photomask. Finally, the substrate is developed in solvent to eliminate the remaining photoresist that hasn’t been exposed [6, 7]. Martinez et al. [1] demonstrated the photolithography technique and used SU-8 2010 photoresist to create patterns on chromatography paper, then soaked and deposited the photoresist onto the paper. Now, the paper was baked for a few minutes to take off the cyclopentanone in the SU-8 formula. After that, a photo mask that had been precisely aligned with the aid of a mask aligner was used to expose the paper to UV light for couple of seconds. Although SU-8 is pricey and the procedure is complicated, the manufactured PADs have good resolution. Furthermore, Whitesides and colleagues used a SC photoresist [8] and an epoxy negative photoresist [9] for the SU-8 2010 photoresist.Fig. 4 Diagram showing the photolithography process. a Chromatography paper, b soaking the paper in a photoresist, c after prebaking aligning under a mask, d exposure to UV light, and e cleaning the developed pattern Wax patterning Wax is a hydrophobic substance that can be used on the hydrophobic surface using different ways. There are many benefits of using wax printing for the patterning of devices, including ease of fabrication, non-toxicity, disposability, and lower production costs. In 2009, Lu et al. [10] created a new wax impregnation process known as wax printing. Molten wax, as opposed to ink or toner, is imprinted on the surface of the paper by solid ink printers used for wax printing [11, 12]. Heat is applied to a piece of paper with a wax design printed on one side in order to flow the wax and permit it to reach the paper’s thickness [13, 14]. This creates a hydrophobic barrier that is entirely impermeable and has a hydrophilic zone enclosed inside it that is shaped like a wax printing pattern. To prevent the reverse side of paper from becoming wet and to stop the permeation-related leakage of reagents and samples to the other side, a clear tape [15, 16] or laminated film is lastly applied to one side of the paper. While the wax is heated, it spreads both laterally and vertically, therefore this must be taken into consideration when drawing the designs. Channels of various sizes can be produced by printing wax in a variety of thicknesses or quantities. Wax dipping Compared to photolithography, it is a more expedient and economical printing method. It only requires wax dipping, and the channel was created in under a minute using subsequent soaking and standard heating techniques [13]. Hydrophobic barriers were created using melted wax, and hydrophilic channels were shielded using an iron mould as in Fig. 5. The magnetic field of a magnet was used to apply the iron mould to the paper. The paper absorbs the molten wax whenever the specimen is submerged in it, but some sections of the iron mould are shielded from the wax’s absorption. The size of the iron mould that is used determines the precise width of the manufactured microfluidic channel.Fig. 5 Diagram showing the wax dipping process. a Filter Paper, b a magnet was mounted to the rear of a glass slide to generate an assembly of paper between a glass plate and a mould, c assembly was submerged in a wax chamber, d peeling off the glass plate and detaching the iron mould at room temperature resulted in the creation of the hydrophobic and hydrophilic regions of the μPADs Inkjet printing In this method, a solvent is used in place of ink to pattern paper using a commercial inkjet printer. One application of this method involves first totally hydrophobizing paper by soaking it in a polystyrene solution. The paper is then treated with toluene inkjet printed in a specific pattern to remove some of the polystyrenes [17, 18]. The printers used for inkjet printing are relatively inexpensive and easily available and the reagents used for inkjet printing can directly print onto the device, helping in making an entire device in just one step. Abe et al. [18] used an inkjet-printed device for the sensing of glucose, proteins, and pH and proposed a method for creating mesoporous colloidal nanoparticle ink using an inkjet printer on both rigid and flexible substrates [19]. This technique permits sophisticated vapor responses for multiple-color PC patterns, and variations in color intensity have been seen with the unaided eye. Maejima et al. [20] created PADs using a similar inkjet printing technique. However, they substituted AKD in this instance with a hydrophobic UV curable acrylate composition made of non-volatile and non-flammable substances as shown in 6. After the unique ink had been printed on the paper, hydrophobic barriers were created by curing the material under UV light for 60 s [21]. The drawback of this method is that inkjet printing frequently necessitates the production of many printed layers and can result in print resolution issues. Since a large number of solvents used to emulsify detecting compounds are flammable, which might clog printers or result in errors in the quantity of reagents that are printed.Fig. 6 Schematic diagram illustrating inkjet printing. a Top view of filter paper, b printing of ink pattern, c UV curing on the top side, d bottom view of filter paper, e printing of ink, f UV curing on the bottom side Laser treatment The CO2 laser is the most often utilized laser source for creating paper-based devices. Without support material to shield the material at the back, this can go into anything in a single pass. In order to create microfluidic devices, double-sided adhesive, PMMA, and paper are frequently sliced using a CO2 laser while maintaining the specific value of operational parameters like the strength of the laser and the reading rate to prevent paper cutting. Mani et al. [22] reported a microchip to diagnose tuberculosis (TB) in the human body, which was framed using a laser cutting procedure. This TB ELISA is a fast, low-cost, and magnetically operated platform. The test duration could be halved to about 15 min while maintaining detection efficiencies on par with those of traditional, classical ELISA. Renault et al. [23] considerably enhanced the rate of flow of liquid on the porous chip and decreased nonspecific adsorption by cutting a channel with a laser to create an intermediate hollowed-out sandwich chip sensor (hollow channel). Chitnis et al. [24] proposed a laser-treated microfluidic device with the use of a substrate made of parchment paper. With the use of computer-controlled CO2 optical trimming and engraving machinery, the texture of the parchment paper was altered. The parchment sheet was treated after being spread open and placed on a pedestal. The intended pattern was created on the parchment paper using rapid scanning of the laser beam throughout the face. However, its usage is constrained by the need for expensive equipment and cautious processing. Plotting In the earlier days, 2D plotter was used for the fabrication of PADs. It is a charting tool that can print or plot two-dimensional items on a plane. By altering the type of plotter head being used, one can switch between plotting and printing [25]. Fabrication of PADs often involves the employment of a spray nozzle that emits an ink stream. A 2D plotter sprays hydrophobic ink onto the paper that is within the plotter. Computing systems have the ability to predetermine or regulate the spray pattern. Depending on the density of the ink and its ability to penetrates into the paper at different temperatures, heating the paper after plotting may or may not be necessary. Bruzewicz et al. [26] modified the x-y plotter to print the solution of polydimethylsiloxane (PDMS) in hexane over the filter paper. The hydrophobic polymer entered the paper’s depths and blocked aqueous solutions from entering the filter paper. This process produces inexpensive, paper-based, physically flexible gadgets. An easier approach to creating paper devices was the use of wax pens [10]. Wax was used to trace the necessary patterns across both faces of a piece of filter paper, which was then baked for a brief length of time. Because of the high temperature, the wax may melt and permeate the paper in the precise pattern of channels needed to create a hydrophobic wall. Laser plotting is another plotting technique to create microchannels by using a laser plotter [27]. In essence, the thermal deterioration action that engraves the surface of the chosen material is the basis for the microstructures produced by this technique. Ink plotting is also a commonly used plotting method in which hydrophobic barriers are created on paper using an X–Y plotter and hydrophobic inks are put into pens [26, 28]. The hydrophobic ink is absorbed in the sheet of paper due to the proper selection of ink viscosity and plotter head pressure. Although this method is cheap, the resolution of the pattern is only moderate. The method takes a long time, thus it’s better suited for creating small quantities of devices. Flexographic printing It is a direct and quick manufacturing technique for mass production in a roll-to-roll method as shown in Fig. 7 [9, 29]. On various substrates, commercial flexographic printers can manufacture the devices at very high speeds. An anilox roll is charged with ink, which is then delivered to a paper that is fastened to the impression roll. As an ink, polystyrene solution in an organic solvent is employed at various concentrations. The amount of ink transferred from the anilox roll to the printing plate, which has a design known as the relief pattern, is determined by the numerous cells that surround it. The doctor’s blade removes any extra ink that may still be present in the anilox roll. To distribute the ink to the paper, the anilox roll is turned four times, along with the plate roll and impression roll. Getting enough ink to saturate the paper substrate, the optimization of the printing speed and pressure between rolls is necessary. The pipet is configured to automatically add ink to the ink tank after printing the first layer. After finishing a few ink layers, the anilox roll needs to be washed; otherwise, the print quality begins to deteriorate. The hydrophobic characteristics of the printed layers are influenced by the number of layers that are printed. Flexographic printing is used to print channels through the use of polystyrene ink that had been dissolved in volatile organic solvents. By adjusting the solvent’s viscosity, vapor pressure, and polystyrene content, channels on the device can be printed partially or entirely through the paper. Flexographic printing also uses commercial ink PDMS. For PDMS to cut through paper, multiple replicate print layers are needed.Fig. 7 Schematic diagram illustrating a flexographic printing method b structures created on porous substrate using flexographic printing Ink stamping Due to the simplicity of the stamping method, it has been extensively used by researchers to create PADs using various stamps and inks [30]. The portable stamp used in the stamping method is the only tool utilized to form a pattern on the filter paper, thus it should be simple to make and apply. A PDMS stamp is used to define a fluidic structure by bringing indelible ink into contact with filter paper. Without using any external force, the PDMS stamp was repeatedly dipped into the stone pad that had been wet with permanent ink. This allowed the stamp to make brief contact with the filter paper. Although ink stamping was straightforward and less expensive, the PDMS stamp was made in a very sophisticated manner. The filter paper was dipped into the liquid paraffin, let to cool, and then placed on the surface of the original paper. The hydrophobic barriers were created by transferring the wax from the p-paper to the n-paper using a warmed metal stamp. Since they are quick and inexpensive prototyping methods based on producing ink channels on substrate with a PDMS mark and permanent inks, the double side printing technique developed by Akyazi et al. [31] and the ink stamping method suggested by Curto et al. [32] have recently emerged as alternatives to conventional wax printing. They might be viewed as low-cost fabrication techniques, but their fundamental flaw is that because they involve manual labor, there is little consistency from one device to the next. De et al. [30] developed a new method for stamping that uses paraffin over a substrate made of chemically altered paper with the help of lightweight, portable stainless-steel stamp for quick prototyping of paper-based devices. Screen printing In this procedure, photolithography is used to pattern the desired design on a screen. The model is constructed first, and then solid wax is applied to the filter paper by rubbing it through a screen model. The wax was heated after printing so that melted wax could seep into the substrate and create hydrophobic barriers using a heated plate. Sameenoi et al. [33] applied polystyrene rather than wax onto the paper in a screen printing model. This method is appropriate for modest amounts of PAD manufacturing because screen printing is frequently utilized in the production of pieces of printing materials. This method has the benefit of being compatible with a greater variety of inks. The key drawback is that it is not suited for quick device prototyping because of the high number of screens needed. Plasma treatment Plasma treatment was utilized to construct μPAD by initially making a hydrophobic surface, and then hydrophobic material was then precisely removed by presenting the substrate to plasma over a physical barrier with the necessary pattern. The shield stay helps in the selective itching of the porous substrate and makes the paper sheet a combination of hydrophobic and hydrophilic regions. Alkyl ketene dimer(AKD) and octadecyltrichlorosilane (OTS)are two chemicals that are frequently used to make paper hydrophobic. Both a plasma cleaner [34, 35] and a portable corona generator [36] have been proposed for plasma treatment. Li et al. [34] patterned the paper by dipping it in an AKD–heptane solution and then putting it in a fume hood evaporate the heptane. The AKD was then treated on filter paper by heating it in an oven, making the material hydrophobic. A vacuum plasma reactor was used to process the modified paper while it was positioned between two metal masks with the necessary patterns. Following the plasma treatment, the exposed portions turned hydrophilic. As a typical industrial material, AKD is affordable and easily accessible. However, each pattern is unique to metal masks. The metal masks should be costly and difficult as a result. Fluorocarbon plasma polymerization for the creation of PADs was proven [37]. Two masks i.e., a positive mask and a negative mask were tightly positioned on either side of the filter paper. Afterward, the plasma system made the hydrophobic barrier on sandwiched by puncturing the fluorocarbon. Obeso and colleagues have reported using plasma and poly (hydroxybutyrate) for the production of PADs. The plasma procedure resembles the plasma therapy that was previously mentioned. But in this instance, the paper is dried at ambient temperature after being submerged in various solutions in succession. This method involves producing the paper beforehand, which takes time but results in a straightforward plasma procedure. Chemical vapor-phase deposition Kwong and Gupta [38] first introduced the chemical vapor-phase deposition-based patterning technology for functional polymers, and afterward, the methodology was expanded for pure polymers. A magnet and a metal mask were positioned on either side of the filter paper. The monomer was placed in a sublimation chamber that had been emptied in order to undergo pyrolysis and create radical monomers. These were applied to the exposed area of the paper, where they were subsequently polymerized to form hydrophobic barriers. Then, a similar method for creating PADs that involved vapor-phase layering of pure polymers was published [39]. In the latter procedure, a magnet and a metal mask were placed on top of the filter paper. A suitable quantity of monomers was added to an evacuated sublimation chamber, where they were allowed to evaporate before being pyrolyzed into radical monomers. They were then applied to the exposed surface of the paper and polymerized to form hydrophobic barriers. This technique was also employed to create PADs. The only distinction between the two techniques is the polymer that Chen et al. [40] utilized, a fluoropolymer covering of poly (1 H, 2 H, 2 H-per-fluorodecyl acrylate). Hand-held corona treatment Jiang et al. [41] proposed the fabrication of μPAD using corona discharge and created PADs using a portable corona treater. First, octadecyltrichlorosilane (OTS) was used to make a filter paper hydrophobic as shown in 8. After that, a plastic mask was used to expose the hydrophobic paper to the corona. The portion that was exposed changed from being hydrophobic to being hydrophilic as a result.Fig. 8 Schematic illustration of designing of μPADs: a paper, b octadecyltrichlorosilane (OTS) coated paper, c soft pad and PMMA mask were separated by OTS-coated paper and subjected to corona discharge after assembly, d patterned μPAD Fast lithographic activation of sheets (FLASH) FLASH is based on photolithography in which UV light and a hotplate are the essential tools required for it [8]. In contrast to photolithography, FLASH does not require a clean space. If UV lamp and hotplate are not accessible, FLASH method can still be successfully used in the sunshine. This technique makes it simple to design in paper small hydrophilic channels as small as 200 m. Photomasks are created as previously described. The photoresist is poured onto the paper and distributed evenly during the FLASH process as shown in Fig. 9. In order to evaporate the propylene glycol monomethyl ether acetate (PGMEA) included in the photoresist. During the cooling process, the paper is brought to ambient conditions. A transparency film is applied to one side of the paper, and black construction paper is applied to the other, in order to reduce the reflection of UV radiation. The border of the construction paper should have adhered to transparent film with the three parts. On the transparent film, black patterns were imprinted to distinguish between hydrophilic and hydrophobic regions. Now, a brief UV exposure is given to the FLASH material. The transparency film and construction paper are then taken off. The paper is cleaned with isopropyl alcohol and acetone after soaking in acetone for one minute.Fig. 9 Schematic diagram for FLASH method to fabricate microfluidic device a after applying the photoresist to a paper, sandwich a black paper between an adhesive transparent material, b utilising an inkjet printer to print designs onto substrate, c the paper being exposed to UV light, d peel out the transparent film and black paper from the impregnated paper PDMS screen printing On chromatography paper, hydrophobic barriers are made using the polymer PDMS, which has a very flexible character. This approach involves moving substrates in different directions under the control of a printing table. The chromatography paper is covered with a nylon mesh screen stencil that has been designed according to specifications. After that, PDMS is applied to the surface and rubbed into the chromatography paper to create a pattern over the paper. The patterned paper is dried for 30 min at 120 ∘C before being chilled to room temperature, as depicted in Fig. 10. The comparison of different patterning techniques highlighting their principles, benefits, and drawbacks are mentioned in Table 1.Fig. 10 Schematic depiction of PDMS-screen-printing method. a Chromatography paper b placing the screen on the paper; c, d applying PDMS to the screen; e curing the PDMS-Screenprinted paper in an oven Table 1 Different fabrication techniques and their underlying principles, along with benefits and drawbacks Method Patterning Agent Patterning principle Benefits Drawbacks Photolithography Photoresist Physical blockage of paper pores Good resolution, convenient, narrow width channels Expensive agent and equipment, extra cleaning required Wax Patterning Wax Physical blockage of paper pores Mass production, simple and quick High printer cost, poor resolution Wax dipping Wax Physical blockage of paper pores Mass production, simple and quick Heating required Inkjet printing AKD Chemical surface modification Agent is cheap, mass production Sophisticated steps, requirement of advanced printer Laser treatment Depend on paper types Physical blockage of paper pores Good resolution Require extra steps Plotting PDMS Physical blockage of paper pores Cheap agent, easy fabrication, flexible can’t use for mass production FlexographicPrinting Polystyrene Physical blockage of paper pores Mass production, no heat treatment Polystyrene solution must be printed twice, and various printing plates are needed Plasma Treatment AKD Chemical surface modification Inexpensive agent, very flexible, no heat treatment required Customized masks are required, slow production rate Screen Printing Wax Physical blockage of paper pores Easy process Low resolution Chemical Vapor-Phase Deposition Chemical monomer Chemical surface modification High resolution Expensive FLASH Photoresist Physical blockage of paper pores Quick Expensive, multiple steps PDMS screen printing PDMS Physical blockage of paper pores Enhanced flexibility Low resolution Incorporating operational functionality Although paper is a unique substrate for containing liquids in specific areas and controlling fluid flow without the use of external power, the above characteristics of porous substrates only provide a limited amount of control over fluid transport, particularly over flow rate and direction. These limitations render inappropriate handling of complex chemical matrices and ill-timed performance of multi-step tasks. The early PADs had limited influence in the analytical community because they were incapable of performing complicated tasks. To integrate enhanced capability for handling liquids and enabling safe operation, various functionalities were incorporated into the device. Flow rate control (programming and timing) One of the earliest examples of fluid flow control was made by Martinez et al. [42] in 2010, who created a multi-dimensional μPAD with ‘on’ buttons that could be used only once to change the flow path. When pressed, fluidic channels were connected between layers of porous material and tape that were strategically spaced apart. Until it was pressed, this computerized valve could fully stop the flow. While single-use valves have their drawbacks, this work showed how programmable PADs might be useful for testing or manually regulating the sequence of reactions. Other researchers [43–45] published additional techniques for managing fluidic transport by changing the shape of the channel. When a channel junction changes from narrow to wide, the flow rate decreases. Another way of flow control was introduced by Toley et al. [46] by redirecting the flow through an adjustable cellulosic shunt that was put in the direction of flow and in direct contact with the paper. By wicking fluid via a bridge made of soluble sugars, Houghtaling et al. [47] used a similar idea to digital ‘on/off’ switches, successfully shutting off the flow. Afterward, a water-soluble pullulan film was created by Jahanshahi et al. [48] that performed a comparable function. Multi-step processing Automating multi-step procedures is the first step in the trend toward making PAD tests more functional. By adding numerous steady portions of paper for each step of the reagent addition process, Fu et al. [49] and Lutz et al. [50] examined the successive transportation of various chemicals to a detecting zone. To build an automated sandwich ELISA experiment, Apilux et al. [51] defined numerous flow routes of variable lengths with various chemicals in each path. Li et al. [52] use of magnetically timed ‘open/closed’ single-use valves allowed them to show device control for multi-step tests. The facial tissue that made up each valve was essentially a porous substance attached with a cantilever. At the beginning of time, either the valve was lowered onto the stream, allowing fluid to flow through it, or it was lifted just above stream, preventing flow. The cantilever was activated by a resistor when the stream from the inlet approached the resistor. The intended delay for on-chip processes determined the length of the timing channel. Furthermore, Fridley et al. [53] showed that depending on the manner in which reagents are put in devices, compounds dried in the paper are amenable for multi-step processing. In their method, a single detection zone made by a PAD cut from nitrocellulose was downstream of channels that carried dry chemicals and each was a different size from the monitoring zone. All three reagents in the porous substance attached at the same time and were closest to the detection zone overall arrived and reached the detection zone first. In an effort to cut the price and size of the LFAs development process, Anderson et al. [54] offered a revolutionary platform centered on the adaptability and capacity of an autonomous fluid handling system. The technology was first successfully used to create an LFA for malaria, but it was quickly expanded to allow for the development of LFAs for SARS-CoV-2 and Mycobacterium tuberculosis as well. This automatic system increased both the number and quality of LFA assay development efforts by cutting down on hands-on time, increasing experiment size, and facilitating enhanced repeatability. Another automatic flow shutdown system was created using pullulan, a quickly dissolving polymer [48]. The paper channel is partially replaced by a deflectable capillary channel produced by a dissoluble film, enabling automatic flow control. In order to accommodate time-sensitive or multi-step reactions and tests, the user can manage fluid movement using this time-dependent flow shutdown technology. Switches and valves Device construction must enable effective control over fluid motion and multi-step protocols. A switch was achieved in PAD by manually bifurcating the channel in order to allow or prevent the capillary flow [34]. The valves operate on the idea that exerting pressure on two vertical fluidic channels changes their gap, allowing fluids to wick along the connected channels. However, functioning without controller or actuator, valves are challenging to integrate into paper-based devices. Switches and valves were built on the same platform and were utilized for more specific applications. The idea behind paper-based microfluidic valves is comparable to that of electronic field programmable gate arrays. Likewise, Martinez et al. [42] built a valve mechanism in 3-D μPADs by exerting pressure to close the space between two fluidic channels that were vertically aligned. Fluids can wick along the joined channels by sealing the gap. Then, Glavan et al. [55] and Liu et al. [56] implemented the folding valve concept into an open-channel device and a laminated device, respectively. When channels in folding valves are folded and unfolded, the direction of fluid flow changes; folding the channel past a 90-degree angle stops the flow. In the literature, self-actuated type valves were also mentioned for sample in/ out tests. Newsham et al. [57] examined and modeled multiple configurations of thermally actuated valves to incorporate the valve into an LFIA with exact control over various flow parameters. To specifically characterize the microfluidic properties of PAD, fluorescent nanoparticles were measured using micro-particle image velocimetry. This method identified divergent bulk flow parameters that might explain extra variability in LFIA signal generation. Li et al. [58] demonstrated a self-powered rotating paper-based microfluidic chip with an integrated movable valve to detect thrombin. The sandwich was created by joining the DNA sequence (DNA1) and a DNA sequence ((GOx)-DNA2 modified by the glucose oxidase enzyme in order to get the supercapacitor signal. The (GOx)-DNA2 may then be released and employed to catalyse the oxidation of glucose as thrombin binds with its specific aptamer through strong binding affinity. The required voltage may be generated to refill the paper supercapacitor as a result of the (GOx)-triggered reaction, and a multimeter can monitor its signal. Electrode incorporation The challenge associated with paper-based devices is obtaining low limit of detection with reasonable efficiency due to a dependency on color identification of the human. Electrochemical detection ability of paper devices bridges the gap between conventional paper-based devices and advanced automatic devices. Devices based on electrochemical detection provide great sensitivity and selectivity while also being a good match for low-cost detection. Making a paper-based device compatible with commercial readers like glucometers was a goal of the development process. The most significant factors affecting the performance of an electrochemical device are the electrode’s shape, material composition, and fabrication techniques. Furthermore, various electrode materials are discussed below. Carbon electrodes Due to ease of manufacturing, ease of chemical alteration, and large possible opening in liquids, carbon is a desirable electrode material. For these reasons, carbon was the first material to be used as a functioning electrode in ePADs [59]. Since then, other instances of carbon electrodes and related fabrication techniques have been demonstrated. The dual-based lab-on-paper device created by Apilux et al. [60] demonstrated a quick and easy way to quantify Au(III) using colorimetry as indicated in Fig. 11.Fig. 11 Depiction of the basic design containing three electrodes (working electrode (WE), counter electrode (CE), and silver/ silver chloride ink as the reference electrode (RE)) screened on patterned paper 1. Screen-printing It is widely used method for fabricating carbon electrodes [61–64]. Polymerizing photoreactive polymer-coated screens around masks is commonly accomplished through photolithography. Another technique involves printing through a silk screen-adhered solid film with a craft- or laser-cut pattern. For the electrocatalytic detection of thiols, Dossi et al. printed an electrode that was combined with cobalt phthalocyanine [65]. Graphene or nanoparticles have also been used in other examples to increase the performance of screen-printed carbon electrodes (SPCE) [66]. 2. Stencil-printing Screen printing and stencil printing are relatively similar processes [67]. This technique uses transparency film or sticky tape to make masks instead of the usual screen materials. Using craft or laser cutters, stencils are easily made. In order to maintain pattern fidelity while stencil printing as compared to screen printing, more dense ink is required so the electrode material is dispensed via an open hole as opposed to a mesh. Viscous ink improves electrode conductivity but reduces the endurance of the electrodes and the adhesion of the paper [68, 69]. The improvement of ink viscosity and composition can help either screen printing or stencil printing. 3. Pencil drawing For inexpensive aqueous and nonaqueous media detection, graphite pencil leads are also used to make electrodes on paper. Santhiago et al. reported using the graphite pencil concept to create electrodes for a paper-based device [70]. For precise detection, lead and graphite were first polished before being put in touch with the paper device. In early works, H-type pencils were used to create the electrodes in order to get a satisfactory electrochemical reaction. However, more recent studies have discovered that soft lead, which has a greater graphite-to-binder ratio, is the ideal material for creating conductive electrodes on paper. Dossi et al. [71] established the concept of pencil lead production after recognizing the significance of binders composition in electrodes. Different binder compositions and additives, such as decamethylferrocene or CoPC, were used during the pencil lead’s fabrication to enhance performance and serve as a mediator during electrochemical detection, respectively. 4.Painting carbon electrodes Painting carbon ink on electrodes directly, without using masks, is one direct way of electrode production. On apply a handmade CNT ink to the substrate and then slice it into strips, all you need is a paintbrush. To create a potentiometric sensor electrode for the measurement of potassium, ammonium, and pH, an ion-selective membrane is applied to the strips. Utilizing precut sheets of paper to outline the painting area results in more repeatable electrode geometries [72]. The mixture of carbon black and readily available carbon inks made up the ink. Metallic electrodes Based on either electrode modification procedures or innate electron transport processes, metallic electrodes provide a wide range of choices for electrochemical detection. The most widely utilized techniques for creating metallic electrodes are thin-layer deposition by sputtering and evaporation. 1. Thin films It is an indirect technique for making electrodes in which metal is placed on paper after a mask has been used. By depositing metals onto the paper using sputtering, evaporation, or spraying, the paper gains conductive characteristics. Sputtering was used to deposit gold on polyester to form a metallic electrode. This electrode was used to quantify the discharge and separation of an ascorbic acid and uric acid mixture specimen on paper at clinically significant concentrations using amperometry. Then, using a metal mask and a gold-sputtered technique, 200 nm thin film electrodes were made in order to identify paracetamol and 4-aminophenol from a particular test [73]. Sputter coating is used to create platinum electrodes, which are subsequently adhered to solid substrates and put in close proximity to the paper. The flow injection detection of glucose in urine was carried out using sputtered electrodes. In urine samples, hydrogen peroxide was discovered amperometrically as a result of the reaction between glucose and glucose oxidase. 2. Wires Compared to electrodes made of carbon ink, microwires are always thought to be a superior electrode choice. Microwire electrodes have a lower resistance than conventional electrodes, which improves the electrochemical response during detection. Additionally, they are simple to clean and/or adjust before incorporating into equipment like gold. Microwires were cleaned with piranha solution to enhance the electrochemical reactivity [74]. Employing thiol-based chemistry, which connected an inner monolayer with a negative terminal, the electrodes were subsequently altered to only react to positive analytes. 3. Microelectrodes Santhiago et al. [68] created the first microelectrode for a paper-based device to carry out an operation identical to stencil printing, but instead of printing directly onto the paper, they used a laser to carve very small holes into a translucent sheet, which they then filled with carbon paste as seen in the picture. For electrochemical detection, elliptical microelectrodes were created using laser ablation. On the back of the transparency, several backfilled holes with a single electrical connection were constructed in order to carry out microelectrode array detection. With more microelectrodes in an array, the limiting current value for sigmoidal voltammetric curves rises. 4. Nanoparticle modification A technique to alter the printed electrodes on the paper involves the deposition of nanoparticles. Nanoparticles can change a material’s conductivity, modifying chemical functionality and expanding the surface area of electrodes. On SPCEs that are available for purchase, Pt nanoparticles were electrodeposited [75]. Pt boosted the measured current response at the electrode surface by catalyzing the oxidation of hydrogen peroxide. On the surface of the working electrode, gold clusters were also formed using electrodeposition. With the aid of gold-thiol chemistry, the gold enhanced the electrode’s surface area and made it possible to attach capture aptamers. Au nanoparticles were placed on cellulose fibres treated with graphene to boost the accuracy and durability of the framework for DNA detection [76]. Additionally, Au nanoparticles were deposited on the fiber’s surface, forming an interconnected layer that served as the basis for a special working electrode [77]. High conductivity and electrodes with a large surface area are produced using these manufacturing techniques. Connections In order to generate power, μPADs can use paper-based batteries; nevertheless, according to WHO guidelines, a flawless diagnostic device would operate without the use of additional batteries [78, 79]. These fluidic batteries are constructed so that the power supply is near the test, making it simpler to connect them. The fluidic battery cannot operate until the sample is placed inside the device. As a result, the sample can be utilized to power any required assay-related components in addition to conducting an assay. Due to integrated galvanic cells, fluidic batteries may provide the appropriate voltage or current. These cells can also be changed to incorporate the smallest amount of electrolytes and electrodes required for a specific procedure [80]. Detectors and readout The production of an effective paper-based device requires patterning, but patterning by itself cannot produce a suitable device unless a decent detector is built into the device. The analyte should be able to be quantified by a paper-based instrument. A single analyte was first detected by a device; however, as paper-based microfluidic devices advanced, the idea of numerous monitoring areas to capture many analytes within a single device was introduced. After printing hydrophobic patterns onto the hydrophilic paper, sensing zones can be created by spotting chemicals in the monitoring areas. The main objective of creating accurate and user-friendly devices is to eliminate the need for external instrumentation. When a ‘yes/no’ response could determine therapy, quantitative or semi-quantitative detections or readouts are preferred for on-site diagnostics devices. The most popular method for non-instrumented analysis is the employment of an externally or internally placed visual color intensity comparator. The technology is now compatible with smartphones and detectors like CCD, CMOS, flatbed scanners, etc. that are reasonably affordable and simple to use with only light to moderate training. Due to a number of factors, mobile camera technology has evolved significantly in recent years. As a result, new opportunities for using PAD technology to investigate detection in various situations have arisen. The techniques for quantitative feedback described in this study include equipment-free methods, digital cameras, and mobile phone cameras. Smartphones and digital cameras Smartphones have created a wide range of new options for analysis in contexts with limited resources, whether by on-site analysis or distant data transmission to a single location. Information can be captured remotely and kept for subsequent transportation to a central location because to the device’s enormous data storage capacity, eliminating the requirement to carry samples. In addition to having a digital camera and a light source, modern smartphones are also capable of doing tasks that would often be performed by costly spectrophotometers, fluorometers, or silicon photodetectors. Smartphones have been used to identify drugs, biomarkers, explosives, dangerous metals, and bacterial and phage infections. Smartphones operate more quickly than flatbed scanners, however, because ambient light conditions change, image intensities are inconsistent. A smartphone intensity-correction app was created to address this issue, or detection could also be made by physically blocking ambient light while taking images. Handheld devices In the past, POC applications, which can cost over 10, 000, required bulky, benchtop instruments. Although these paper devices are effective for POC applications, they do not meet the ASSURED criteria (device must be Affordable, Sensitive, Specific, User-friendly, Rapid and robust, Equipment-free, and Deliverable) of the WHO for the medical or environmental community as mentioned in the preceding section due to their pricey integrated pieces. Therefore, the detector cost-structure system must be substantially lower. For simultaneous amperometric detection of glucose, lactate, and uric acid, a low-cost eight-channel potentiostat was developed [81]. The design of the gadget for multiple electrochemical detections at once included eight unique bespoke electrochemical wells. In a handheld potentiostat more recently, 48 channels were added [82]. A portable potentiostat that can mix samples on board, execute a variety of electrochemical assays, and wirelessly send analytical data over speech through a cellphone audio connection is made for environments with limited resources. It was intended for this data transfer to make older consumer phones compatible with their system. It has also been stated that other commercially available handheld instruments may measure water contamination electrochemically or explosively using fluorometry. Detection techniques Microfluidic devices based on paper have been proposed with several different detection techniques. These detection methods have applications in environmental testing, food pathogen detection, medical diagnostics, power generation, etc. Colorimetric detection It is currently one of the frequently utilized methods for detection in PADs because of the benefits of a visible interpretation, quick detection efficiency, practicality for rural field applications, simple operation, and good stability. In colorimetric detection, the analyte solution is passively transported by capillary action to the test zone of the apparatus, where it reacts with properly positioned reagents to generate a perceptible color change. Basically, the digital/CMOS cameras, scanners, or cell phones used in PAD colorimetric detection systems are used to capture the detection zone images, which are then sent to a computer or a mobile device for processing. For colorimetry-based analysis, LFAs are the most popular PADs. Because LFAs are simple to use, biodegradable, quick, and lab-free, they are beneficial for POCT and allow for the quick sensing of biomolecules like proteins in complicated samples without prior pretreatment. The majority of commercial LFAs that rely on optical sensings, such as HIV testing, pregnancy tests, and other bios studies, have been developed using aptamer- or protein-labeled gold nanoparticle (AuNP) conjugate probes. A PAD for the identification of acetylcholinesterase activity and inhibitor screening was created by Liu and Gomez [83] based on colorimetric sensing. The fabrication of the PAD used a direct wax printing procedure in which wax was applied to the paper to form the hydrophobic barrier. Cardoso et al. [84] proposed a variety of colorimetric PADs for the measurement of numerous analytes, like whiskey, BSA, tear glucose, urea, ketone bodies, nitrite, glucose, bilirubin, etc [85, 86]. To detect Hg+2 ions, Meelapsom et al. [87] created an Ag nanoparticle-processed multi-layered PAD employing thick paper and an ink-jet printing technique. The Hg+2 ions used in the detecting procedure oxidized the Ag nanoparticles, causing them to break up into smaller particles, reducing Hg+2 to Hg, and the detection zone’s color is changed from deep yellow to vibrant yellow. It was demonstrated that the gadget could detect particles as small as 1×10-3 ppm. A PAD was created by Yamada et al. [88] to deliver the findings of chemical analysis in the manner of ”text” by combining the utilization of a conventional colorimetric indicator with an inert colorant. Protein in urine has been utilized as a proof-of-concept model analytical target. Human urine was used in user tests, and the results showed that the created device’s accuracy was on a level with a conventional dipstick. For the colorimetric detection of Hg+2, Cd+2, Zn+2, Ni+2+, and Fe+3 ions in drinking water or effluent using chromogenic chemicals, Mujawar et al. [89] proposed a PAD for recycling waste to create low-cost analytical devices. The Fe+3 ions were determined using an extremely reactive 2-hydroxy-1-naphthaldehyde (HyNA) reagent in an optical assay plate with conical wells. An excellent limit of detection and limit of quantification of total Fe+3 ions were achieved. The proposed approach proved successful in detecting and precisely determining Fe+3 ions in tap and marine water samples. Chowdury et al. [90] proposed a μPAD added with a nanosensor made of gold and functionalized with α-lipoic acid and thioguanine for detection of arsenic in hand tubewells water. By raising the pH of the PADs to 12.1, a technique was created to prevent the influence of the alkaline metals (Ca, Mg, K, and Na) prevalent in Bangladesh groundwater. This test, which evaluates if the concentration of arsenic in the water is beyond or under the WHO recommended limit of 10 g/L, was the inaugural paper-based test to be approved using water samples from Bangladesh. Liu et al. [91] demonstrated an effective framework consisting of a paper-based/PMMA chip with a colorimetric sensor to measure SO2 concentrations. The sample in the suggested apparatus was kept on a small piece of paper that had been treated with an acid–base marker before being placed inside a PMMA microchip. It was shown that the SO2 percentage results taken for 15 industrial food samples using the suggested methodology deviated from the values obtained using a recognized macroscale approach by a maximum of 4.29 percent [92]. Mahmoudi et al. [93] designed a colorimetric PAD for rapid and hands-free telomerase activity sensing by utilizing color shift in accordance with enzyme activity. The telomerase was extended along with a biotinylated probe and an oligonucleotide that was complementary to the telomeres. The hydroxylamine hydrochloride approach for enlarging the AuNPs allows for a signal enhancement that results in color that is apparent to the naked eye once the assembly has been joined. With a measurement range of 6 to 25,000 cells, visual telomerase activity identification was achieved down to 6 cells when the analytical performance of the enzyme extracted from breast cancer cells was assessed. The hue of the porous sheet evolved from light-red to light-red-blue to black-red with increasing telomerase content. Fu et al. [94] suggested a colorimetric assay for telomerase activity detection on functionalized cellulose paper using methylene blue (MB) as a colorimetric probe and was focused on telomeric elongation and collecting amplification. The telomerase substrate was placed onto sterile cellulose paper (TS). Telomerase will lengthen this primer, resulting in a long single DNA that will further catch more probes and raise the assay’s responsiveness. When MB-labeled oligonucleotides hybridize with sDNA, the color will change. Signal strength is correlated with sDNA content and hence with telomerase activity. Oligonucleotides are unable to hybridize with sDNA when telomerase is not present in the samples. Telomerase will stretch this primer to generate a single DNA (sDNA), which will further attract more probes and improve the sensitivity of the assay. The color will change when MB-labeled oligonucleotides hybridize with sDNA. The quantity of sDNA and thus the activity of telomerase is associated with signal strength. In samples lacking telomerase, oligonucleotides are not able to hybridise with sDNA. Electrochemical detection Dungchai et al. [59] merged the concept of electrochemical detection with μPADs. The channels in chromatography paper were created using photolithography and carbon electrodes were printed using screen-printing techniques. By sensing uric acid, lactate, and glucose in biological samples, Dungchai and coworkers further demonstrated the device’s biosensory capacity. The three different electrodes in this trial are changed with lactate oxidase, glucose oxidase, and urease, respectively, by adding enzyme solution into the corresponding test region. Diabetes is a very common disease and the glucose levels of the patient must be continuously monitored in an easy way. In order to measure glucose levels, Fernando et al. [95] created an electrochemical microfluidic paper-based analysis device (PAD) that utilises sweat and saliva as a sample. The creation of a three-electrode system uses pseudo-reference stainless steel and a working electrode that has been anodized using sodium potassium tartrate tetrahydrate. With a limit of detection of 0.058 mmol dm-3 and a working range of 1 to 10 mmol dm-3, cyclic voltammetric-based assessment of glucose using PAD achieved a linear response. Fonseca et al. [96] gave the basic concept of making disposable ePADs by employing screen printing and inexpensive materials. All the devices were built utilizing liner paper as a base and carbon ink that was made with wood glue and graphite powder. The ePAD was assessed as a biosensor and electrochemical sensor. Moreover, Tomei et al. [97] fabricated a strip to identify the level of glutathione in blood. A filter paper was used as a substrate where WE and CE were screen-printed, hydrophobic channels were wax printed and then the solution was confined in an area to prevent diffusion of electric contacts. The loaded cystamine on WE and the glutathione, which was liberated by blood lysis, engage in a thiol-disulfide exchange reaction, which is the basis for the detection. Due to the electrocatalytic abilities of Prussian Blue included in the WE, this reaction results in cysteamine, a molecule readily oxidizable. Ruecha et al. [98] proposed a label-free disposable PAD to detect human interferon-gamma (IFN-γ) by making three electrodes on the Whatman filter paper grade No. In order to screen print the working electrode (WE) and the reference (RE) and counter electrodes, the wax-patterned device was divided into two tabs (CE) so that they can fold over one another. The working electrode was made with graphene ink and polyaniline to immobilize human IFN-γ monoclonal antibodies covalently. Wang et al. [99] developed an origami-style device to detect breast cancer MCF-7 cell line. Three spatially isolated sections of wax and a screen-printed WE of carbon were printed on paper grade 2. The hydrophilic zone in the reference region also has a carbon CE and an Ag/AgCl RE. The produced Au@3D-rGO was then coated with the MCF-7 cell-specific aptamer H1. To make it straightforward to combine the full screen-printed, three-electrode electrochemical cell, the different patterned pieces of the paper component were wrapped in a two-step folded pattern once the solution had been added. Likewise, Moazeni et al. [100] detected the biomarker of tumor i.e., α-fetoprotein in human serum by embedding finger-type silver-carbon electrode pairs on paper substrate. The devices were created using a top layer of a substrate treated with aldehydes and a lower flexible sheet of plastic. Diphenylalanine nanostructures were positioned on the paper to integrate different groups and help with the covalent immobilisation of antibodies to the target compound. To detect CEA in samples of human serum, another paper employed the multilayer structure. On a section of the device with structure, a molecularly imprinted polymer (MIP), which was electro-synthesized in the presence of the target analyte, was electro-synthesized and used as the particular receptor for these target analytes. In a different but identical portion of the device, a non-imprinted polymer was created in the same way as the MIP [101]. Also, for the rapid and easy identification of infectious diseases, brought on by pathogenic microorganisms by aiding affinity-based biosensors and amplification of the genetics were used in many papers. Like, He at al. [102] created an origami style PAD to identify the salmonella pathogen Salmonella typhimurium by combining wax and screen printing. By flipping the various origami pieces, the device was used to execute cell lysis, DNA extraction, and LAMP. When compared to PCR results, the device could identify the pathogens in whole blood with a sensitivity of 82 percent and a specificity of 91 percent. Finding antibiotic resistance is an intriguing strategy for managing infectious diseases. Santhiago et al. [103] described the electrochemical characterization of a 3-D PAD for p-nitrophenol analysis. The filtration-integrated PAD was made using regular printing paper that had been wax-printed with a design to allow quick evaluate p-nitrophenol information with a quick response code. The instruments were used to measure the presence of p-nitrophenol in water samples, with a recovery rate varying from 91.8 to 108.2 percent. Nowadays, cardiovascular disease (CVD) is the major cause of death worldwide. As a result, for the diagnosis and monitoring of illnesses, a sophisticated and reasonably priced POC-detecting device is required. Bookaew et al. [104] made an ePAD to simultaneously measure three key CVDs biomarkers, including C-reactive protein (CRP), troponin I (cTnI), and procalcitonin, using a label-free immunoassay. The sample inlet, all detection zones, and their connecting channels were defined by wax on the paper. They used square wave voltammetry to measure the concentrations of the CVDs biomarkers (SWV). When the cardiac marker was present, there was a noticeable reduction difference in the response curve in a concentration-dependent manner, even though there was no discernible difference in the response curve when it was absent. Yakoh et al. [105] designed two models for fluid delivery in a μPAD that can successively store and transport reagents to the required zone without an external source. This 3D capillary-driven device was made of origami folded paper and a portable pad for electrochemical detection of biological organisms to illustrate the breadth of this technique. The single buffer injection was developed for ascorbic acid sensing utilizing a flow-through arrangement. They extended the usefulness of the device to integrate experiments by adopting a stopped-flow mode. Fluorescent detection It is centered on the estimation of the amount of light that a material emits after having first absorbed electromagnetic radiation. It typically encounters problems in PADs because a commonly available paper with chemicals that also self-fluoresce and generate a lot of background noise. However, numerous fluorescence sensors incorporated with any textile material have been created and have poor sensitivity. Wang et al. [106] illustrated a cloth/paper hybrid μPAD for identification of mercury(Hg+2) and lead (Pb+2) ions in water. After adhering quantum dots to the cotton cloth, ion-imprinted polymers were employed to alter the fluorescence-detecting cloth-based component (IIP). The limits of detection for the fluorescence signals were achieved using fluorescence quenching action. Zhu et al. [107] tested Alkaline phosphatase and butyrylcholinesterase simultaneously by 3D origami μPAD in which sample-in-result-out platform fitted. These two indicators were also used in a rationally designed cascade catalytic reaction for sensing ALP and BChE. Using appropriate metal molds and one-step mapping with a black oil-based pigment, a 3D origami PAD with 4 levels and two parallel channels was created. Using a smartphone camera and red-green-blue software, fluorescent images on the detecting region can be obtained after simply folding the paper and then again unfolding nearby surfaces to begin the reactivity of charged chemicals. Under ideal circumstances, the suggested platform was used to sense ALP and BChE in human serum samples do not necessitate any preparatory procedures. Shi et al. [108] proposed a simple method for creating carbon nanodots that are nitrogen-doped in yellow fluorescence (y-CDs). The 4-amino salicylic acid was used as the precursor compound in a one-step hydrothermal process without further surface passivation or modification to create the sensor strip of paper comprising y-CDs. These y-CDs have been used for intracellular Al+3 imaging and paper-based Al+3 sensing in living cells without interference from autofluorescence because of these outstanding features. In order to detect Hg+2 ions, Zong et al. [109] created the reversible red fluorescent probe the (NDI-5), which was primarily composed of the receptor bis[2-(3,5-dimethylpyrazol-1 yl)ethyl]amine and the strong electron-withdrawing unit naphthalene diimide. The probe NDI-5 showed a rapid and selective ‘turn-on’ fluorescence response to Hg+2 ions because the coordination of Hg+2 ions can push the potential twisted intermolecular charge transfer (TICT) in the entire molecule. For the semi-quantitative testing of Cu+2 ions, Liu et al. [110] showed how to make dual-colored CD ratiometric fluorescent test paper. The visual assessment of Cu+2 ions using the ratiometric fluorescent test paper has been effectively created in multiple key areas. (1) The remaining p-PDA effectively binds Cu+2 ions on the surface of r-CDs. (2) The Cu+2 ion functions as a link, allowing the small b-CDs to be transferred onto the surface of larger r-CDs by its double coordinating connections with the surface ligands of both r-CDs and b-CDs. (3) The b-CDs undergo a particular spectral energy transfer to the r-CD-Cu+2 complex. Chemiluminescence detection Another sensitive and effective detection method for PADs is chemiluminescence sensing. The method shines in terms of its ease of use, fast response, and interoperability with micro technologies, enabling numerous applications, even for those who are not trained [111]. However, the sensing must be done in the dark, which makes it more difficult to make the device. Portable chemiluminescence readers are also required for this procedure. The chemiluminescence (CL) technique and μPADs were integrated for the first time by Yu et al. [112] to create a unique CL PAD biosensor. The oxidase enzyme reactions and the chemiluminescence reaction between a rhodanine derivative and produced H2 O2 in an acid medium are the foundations of this lab-on-paper biosensor. This CL PAD biosensor was skillful in quantitatively determining uric acid with accurate and satisfying results. Then, the same researcher [113] created a PCAD to sense both glucose and uric acid in fake urine simultaneously. They discovered that by varying the ranges that the samples traveled, it was feasible to simultaneously measure uric acid and glucose. Al et al. [114] invented a portable PAD for on-site screening of dangerous mercury ions (Hg+2) in cosmetics with a limit of detection of 0.04 g ml. It is founded on the fundamental ability of quantum dots of carbon (CQDs) to function as an excellent emitter for the bis(2,4,6-trichlorophenyl)oxalate (TCPO)-hydrogen peroxide (H2O2) CL reaction. Zangheri et al. [115] created a biosensor that uses a CL-lateral flow immunoassay (LFIA) technique to detect salivary cortisol quantitatively using a smartphone app. The biosensor works by using a peroxidase-cortisol conjugate in a direct competitive immunoassay and detecting the result by incorporating the chemiluminescent substrates enhancer/H2O2/luminol. It provides quantitative analysis between 0.3 and 60 ng/ml for the therapeutically appropriate range of salivary cortisol detection. Electrochemiluminescence Electrochemical processes are the basis for electrochemiluminescence sensing methods, which produce luminescence. When electrochemically produced intermediates go through exergonic processes, they enter an electrically excited state. As they unwind and become more tranquil, the molecules in this condition produce light, enabling monitoring systems without a photo-detector being necessary. The ability of electrochemiluminescence sense to be enforced to both luminescence and electrochemical sensing techniques is its most notable characteristic. In comparison to chemiluminescence, electrochemiluminescence also has some benefits, including a decreased background, the ability to manage reagent synthesis, and greater selectivity through potential control [116]. Delaney et al. [117] firstly merged paper microfluidics with electrochemiluminescent (ECL) detection by paring inkjet-printed paper with screen-printed electrodes, that may be read without a conventional photodetector. For the first time, Wu et al. [118] created a paper-based electrochemiluminescence (ECL) origami device (PECLOD) and combined the rolling circle amplification (RCA) method with oligonucleotide functionalized carbon dots (CDs) to create a cascade signal amplification method for the sensing of IgG antigen. The RCA product’s tandem-repeat cycles could serve as an excellent model for the regular construction of CDs, which would then display many CD tags for ECL readout per protein recognition event. The recently suggested wax-printed 2D μPADs based on immediately screen-printed electrodes on paper was the first to incorporate electrochemiluminescence (ECL) immunoassay [119]. Four tumor markers were identified using a standard tris -(bipyridine)- ruthenium - tri -n- propylamine ECL system in actual clinical serum samples. Eight working electrodes were consecutively inserted into the circuit with the help of a simple mounted and a section switch included into the analyzer to start the ECL response in the scanning band between 0.5 to 1.1 V at ambient conditions. Yan et al. [120] included electrochemiluminescence immunoassay capabilities into wax-patterned PADs that were based on screen-printed electrodes. At room temperature, the ECL reaction was started with the help of a homemade device holder. This paper-based ECL 3D immunodevice was utilized to perform a standard tris(bipyridine)ruthenium-tri-n-propylamine ECL system for the diagnosis of carcinoembryonic antigens in actual clinical serum samples. Theoretical Analysis The fluid moves in the porous substrate can be categorized into two processes, the wet-out process, and the fully wetted flow (as shown in Fig. 12). The wet-out process: the fluid is moving forward the dry porous media. It is modeled using the Lucas-Washburn equation. In the fully wetted flow, the fluid moves along the wetted porous media and is described by Darcy’s law.Fig. 12 Representation of physical mechanisms governing the behaviour of liquids in porous materials Lucas-Washburn equation Lucas and Washburn proposed this model to explain the behavior of liquid wicking in porous materials. The porous microstructure of paper can be compared to a collection of cylindrical tubes where capillary action drives the liquid flow [121]. It is a process of momentum balancing between the hydrostatic pressure, capillary force, and viscous force. According to L–W equation: Inertia force = surface tension + gravity force + viscous force1 ρπr2δδt(h(t)δh(t)δt)=2πrσcosϕ-πr2ρgh(t)-8πηh(t)δh(t)δt where σ is surface tension, r is the radius of the meniscus, ρ is the density of the liquid, ϕ is the equilibrium contact angle and h are distance the liquid front has traveled. The Lucas-Washburn model considers a few key assumptions, including that (i) evaporation does not take place (ii) gravity and inertia forces are neglected, (iii) the fibrous porous material is homogenous, (iv) boundaries have no impact on capillary flow, and (v) wicking liquid is laminar, incompressible, and low viscous. In consideration of these assumptions, Eq. (1) will become,2 2πrσcosϕ=8πηh(t)δh(t)δth=4σcosϕζηϵrt1/2 Where t is the liquid absorption period and h is the length of the paper’s wetted area after time. Since σ,ϕ,η, and r are all constants and the wicking length (h) is proportional to the square root of time the fluid-front velocity drops over time due to the flow resistance provided by porous media’s surface [49]. The aforementioned assumptions place restrictions on Eq. (2). As a result, many changed models are created to provide better explanations. L- W model considering gravity force In some circumstances, it can be challenging to utilize the standard L-W equation to determine the performance of device as different diagnostic tools and experimental paper strips operated vertically. The force of gravity commences existing as a result of fluid flowing vertically. The gravitational force eventually becomes a significant role in the liquid immigration process as the liquid rises, which causes a substantial difference between the theoretical and experimental liquid front. A general correlation between the liquid front and time is created to address this issue [122, 123]. From Eq. (1) we obtain2πrσcosϕ=πr2ρgh(t)+8πηh(t)δh(t)δt The equation can be further written in the scaling form:σrh∼ρg+ηhr2 Therefore, the driving capillary pressure gradient is balanced by both the force of gravity and viscous friction. After integrating the above equationh=2σrtη-ρgr2tη Substituting the radius rl of the leading meniscus (deduced from the condition (δhδr)=0 at r=rl) in the previous equationrl∼ηr8ρ2g2t1/3 we obtain the value of h(t) at r=rl3 h(t)∼σ2tηρg1/3 The connection demonstrates that the h has a linear relationship with t1/3 as shown in Eq. (3). The modified model considering evaporation When the temperatures are high and the relative humidity is low, the assumption that there is no evaporation occurs may cause an overestimation of liquid flow over an extended period in an open environment. By ignoring the gravitational influence, one can examine evaporation, which is consistent with observations on the wetting process [48, 124]. Empirical correlation from the ASHRAE handbook to calculate the rate of water evaporation at each relative humidity,mev=(ps-pp)×(0.089+0.0782hfg)ma where, ps,pp,hfg, and ma are the saturation pressure, partial pressure of water vapor, latent heat of vaporization, and air flow rate respectively. The partial pressure of water vapour in the air and the water saturation pressure at a fixed pressure and temperature are used to define the relative humidity. The relative humidity(π)=ppps Therefore, we obtain4 mev′=(1-π)×ps×(0.089+0.0782×hfg)ma The integral formula can be used to determine the total evaporation mass at every instant in the evaporation model:5 mev=2∫0tmev′wh~dt where, h~ is the expected wicking height of the liquid. The expected wicking liquid mass me at any instance is the difference between the theoretical value mo and the evaporation mass mev,me=mo-mev=ρwδ4σϵcosϕζηrt1/2-2∫0tmev′wh~dt Wicking mass of liquid me can be attained by the wicking liquid density and its volume,me=ρwδϵh~ Therefore, the wicking liquid height can be given by6 h~=mevρwδϵ=4σcosϕζηϵrt1/2-2mev′ρδϵ∫0th~dt By taking a time derivative, the Eq. (6) is recast as:7 dh~dt=Rt-1/2-Sh~ Boundary condition: h~=0, at t=0R=2mev′ρδϵS=σcosϕζηϵr The solution to Eq. (7) is therefore8 h~=2Se-Rt∫0teRt2dt The liquid-wicking process exhibits a dynamic character due to evaporation. Equation (8) represents the wicking distance with due accounting of evaporation from the surface. This adjustment may be needed depending on the particular experiment. Darcy’s Law It was first used in 1856 to describe the fluid flow through a fully saturated porous substrate by Henry Darcy [125]. This model was created using the momentum equation to address the issue of liquid flow in pre-wet porous media under steady-state conditions. By examining how water moves through sand, the viscous pressure loss is written as:9 ∇P=-ηζv where v is the average velocity vector, ζ is the substrate permeability, η fluid viscosity, and ∇P is the pressure drop per unit length also known as Laplace pressure. Using the paper substrate, calculate the fluid’s imbibition rate (v^), the above equation is further expanded to yield:v^=ζi∇Pηh(t) where ζi=ζϵ is the interstitial permeability and the porosity ϵ=1-γρh,γ is the weight, ρ and h are the density and thickness of the paper respectively. Darcy’s law finds out the flow rate Q under a pressure differential ∇P, by using the Navier–Stokes equation:10 Q=-ζγhηL∇P⇒∇P=-ηLζγhQ In this expression, ∇P=P(0)-P(h), where P(0) is the pressure at x=0, and P(l) is the average capillary pressure. A hydrodynamic load term with a general flow resistance Rhyd is also included in the flow domain for the model system under considerationQ=-∇PRhyd The above equation is analogous to Ohm’s law of an electrical circuit, I=∇VR, where I is the electric current, R is the electrical resistance and ∇V is the potential drop. In hydrodynamic systems the volumetric flow rate, Q is the volume per unit of time, while in electric system current is the charge per unit of time. Also, ∇P is analogous to potential drop. Since capillary force is the primary factor influencing analyte transport in PADs, low spontaneous imbibition rates may reduce the detection sensitivity. For building sensitive and precise PADs, a quantitative understanding of internal spontaneous capillary flow progression is necessary. Wang et al. [126] examined the capillary flow in a porous substrate both experimentally and numerically. The authors computationally analyzed the experimental data in order to enhance the prediction of spontaneous imbibition. The quasi-static pore-network modeling of a real filter paper used to establish the equilibrium two-phase flow material parameters reveals that neither the single-phase Darcy model nor the Richards equation adequately anticipates spontaneous imbibition. A new numerical simulation using the finite element method called PORE-FLOW was presented to describe these imbibitional flows in wicks with complex forms [127]. Additionally, two-dimensional (2D) wicking in modified cylindrical wicks with two different cross-sectional areas is predicted using the simulation. Later, the wicking behavior of a few further types of changed wicks with noticeable changes in their cross-sectional areas was statistically examined. It was found that the history of the liquid ingested was related to the height of the liquid front as a function of time. The Richards equation, which accounts for the dynamic capillarity effect, shows the capacity to predict when wetting saturation will begin. Liu et al. [128] used three-width strips of filter paper to measure the liquid mass and height through experimental and numerical investigation. To calculate wicking height and mass, a modified model that takes the evaporation impact into account was developed. It was found that after initially declining sharply, the wicking speed stabilized at a lower level and remained steady. With a wider strip, more wicking mass could be achieved, but reagent loss increases in proportion. Ouyang et al. [129] advanced the use of the numerical simulation method to examine PAD fuel cells. To show how the paper-based microfluidic fuel cell functions as a whole, both transient and steady-state modes were used. Moreover, the effects of several structural characteristics on cell performance, such as electrode spacing, the distance between the electrode and the inlet, channel thickness, and electrode length, were also explored. Results demonstrated that decreasing cell output power to varying degrees, as major structural factors are increased. Modha et al. [130] described the behavior of paper-grooved channels and evaluated how well they function as ‘delay’ mechanisms for a multi-fluid paper-based sensor. Moreover, the author also performed In-silico simulations that can accurately anticipate imbibition in both natural paper and grooved channels. Elizalde et al. [131] hypothetically investigated capillary imbibition in substrates that mimic paper in order to more clearly visualize fluid transport in the context of the macroscopic shape of the flow domain. A model that predicts the cross-sectional profile required for a specific fluid velocity or mass transfer rate has been created for uniform materials with arbitrary cross-sectional shapes. The capillary flow in a closed system is described by two theoretical models that are provided [132]. Both the first and second models account for liquid imbibition into the paper matrix and flow through non-absorbing surfaces (flow in the gap). Significant conformity between the experimental results and the model solutions was found. The provided volume to the flow on the non-absorbing surface was shown to have an impact that improved the forecasts. The influence was found to be minimal at low flow rates but strong at high flow rates. This work demonstrates that the flow dynamics are influenced when a casing is added to a device, despite the fact that several experiments on flow in PADs were carried out on open systems. Employing various width sheets of filter paper, Patari et al. [124] conducted experimental and computational research on the wicking height and mass. Given that there is a linear relationship between wicking height and mass, it is convenient to evaluate the effective porosity. The proposed model with evaporation was required in order to explain the foundations of flowing fluid in testing paper and to provide relevant and useful benchmarks for the creation of PAD. Rosenfeld et al. [133] described an analytical and experimental investigation of a brand-new PAD for sample focusing by isotachophoresis. The author demonstrated that peak enhancement by significant sample focusing (on the order of 1000-fold) may be accomplished in a matter of minutes, despite the fact that dispersion was far more significant in paper than in glass. A handy figure of merit was provided by our analytical approach for assessing the effectiveness of ITP focusing. They demonstrated that, despite the stated improvements, the device’s efficiency was only about 10 percent, meaning the amount of sample accumulated was well below the theoretical upper limit. In microgravity, the phenomenon of absorption in a porous substrate underneath the presence of capillary forces was studied [134]. The impact of non-stationary and convective factors on the imbibition process is examined in the analysis of the momentum conservation equation. The outcomes of numerical modeling of the recurrent imbibition process under the influence of capillary forces in microgravity in an irregularly shaped porous material are reported. The mathematical model of the imbibition phenomenon was presented by More et al. [135] to compare the saturation level for different time and distance levels that have been discussed between homogeneous and heterogeneous porous medium for various types of sands. Numerous natural and industrial processes can be benefited from spontaneous imbibition. Using the phase-field method, numerical simulations of counter-current absorption in porous media with various pore structures were carried out [136]. According to the simulation results, heterogeneous porous medium produced more oil than homogeneous porous media did. According to evidence, counter-current imbibition was significantly influenced by the differential between capillary driving pressure and capillary back pressure, which were both directly related to the pore structure and pore size distribution of porous media. Wang et al. [137] used numerical simulation to examine the paper-based microfluidic fuel cells in both transient and steady-state modes. Additionally, the effects of several structural characteristics on cell performance, such as electrode spacing, the distance between the electrode and the inlet, channel thickness, and electrode length, were also explored. The findings accelerated the development of microfluidic fuel cells by serving as both a theoretical foundation and a point of reference for the next optimization efforts. Applications Medical diagnosis Point-of-care (POC) diagnosis is crucial for both the diagnosis and treatment of diseases. The objective of POC is to offer a solution when a sample is delivered to the equipment to make an informed decision. The main goal of paper-based microfluidics is to give developing nations a platform for low-cost illness diagnostics and environmental monitoring. It emerged as less priced, simple to use, and portable analytical test equipment. The development of medical science is aided by cutting-edge research in the field of PAD that provide quick, effective POC diagnostics. Due to the appealing features of PADs (low cost, no external pumping system needed, multiplexed assays, etc.) and their clinical applications, their range has expanded to POCs in resource-poor environments, home medical care, and severe disease biomedical diagnosis. However, the technology is semi-ready, and it still needs further development to achieve proper quantitative analysis. Here are some of the most important applications of PAD in the medical field: Plasma separation Since most medical diagnoses require a blood test as a prerequisite or necessary step, blood is the most important clinical analyte. The accurate interpretation of blood can deliver extensive information about a candidate’s physiological state, enabling effective pathological diagnosis. The examination of blood, which is a complicated mixture of red blood cells, white blood cells, plasma, and other necessary components, is challenging. Because it transports all the vitamins, proteins, and minerals throughout the body, it controls all hemostatic and physiological parameters and could be used as a diagnostic analyte. First, the serum must be isolated from whole blood to be clinically diagnosed. For diagnosing either erythrocyte-related information or a routine concern of the other blood constituents excluding the erythrocytes, the separation of plasma from that of the whole blood is always the first step. Due to the presence of erythrocytes during the diagnosis, it is frequently difficult to detect a complex analyte like blood utilizing colorimetric, fluorescence, and chemiluminescence methods. These red blood cells may agglutinate and interfere with biochemical processes, as well as convert chemical signals to optical signals when used with color-based or optical-based sensing technologies. Erythrocytes influence the rheological dynamics of the blood in electrochemical detection situations. Therefore, separating the plasma from the erythrocytes is a step that must be taken while diagnosing blood. The use of RBC-specific adherent membranes, which permit plasma to pass through the paper, is the most used method for separating RBCs [138]. To separate RBCs from whole blood, electrochemical techniques [139] and agglutination reagent [140] have attracted interest as they could directly operate the whole blood sample as shown in Fig. 13. A cheap paper-based platform was created by Kar et al. [141] to extract blood plasma from a whole blood sample. They created a paper gadget based on the elegant separation method and the straightforward origami method, where the complete device is built by folding a single sheet of flat paper. This technique can be used to quickly identify sick states in blood samples without the use of experienced workers or specialized lab settings. Another device for separating plasma from whole blood and determining glucose concentration was described [142]. This device does not require a membrane to separate the plasma from the whole blood sample and will be helpful in creating POC testing equipment that can identify analytes in small sample quantities. A BPS PAD was created by Burgos et al. [143] to identify and measure the S100B biomarker in peripheral whole blood. The VF2 collecting pad, which conducts vertical and lateral plasma separation was added with the complete blood sample. As a result of the cells creating and becoming trapped in the VF2 matrix due to hypertonic circumstances, the addition of NaCl to the VF2 pad causes RBCs to aggregate and increased plasma wicking.Fig. 13 Schematic diagram of the RBC agglutination to increase the effectiveness of filtration to separate blood plasma from entire blood. a Due to their deformability, RBCs can pass freely via filters. b RBCs cannot pass through filtration with pores smaller than 2.5 mm, while the flow of segregated plasma is severely hampered by small pores. c Large multicellular aggregates made of agglutinated RBCs might be removed utilising filters with large-diameter pores, allowing for faster flow rates of segregated plasma through the filters Blood typing The classification of blood due to the presence of antibodies and hereditary antigenic compounds on the surface of red blood cells is known as blood typing. For several medical operations, including blood transfusion and transplantation, it is important to know your blood type [144]. The situations of hemolytic transfusion reactions and other deadly outcomes can be avoided with the accurate identification of blood groups. The earliest techniques for blood typing relied on laboratory-based equipment, which does not adhere to WHO’s ASSURED recommendations. Gel columns [145], thin-layer chromatography (TLC)-immunostaining [146], are the traditional blood-typing methods. In order to determine the blood type using agglutinated and nonagglutinated red blood cells. Khan et al. [147] proposed an inexpensive, appealing paper-based alternative. A piece of paper that had been treated with an antibody was the subject of an investigation by Jarujamrus et al. [148] The network of paper fibers becomes tangled with a mass of agglutinated cells that are produced when antibodies are desorbed from cellulose fibers. The assay performance influencing variables have been investigated, including antibody stability, papermaking additives, and paper structure. Larpant et al. [149] simultaneously suggested a simple and low-cost PAD for phenotyping RBC antigens. Using this Rh typing method, five Rh antigens on RBCs can be recognised and observed under a microscope in less than 12 min. The suggested Rh phenotyping is dependent on the hemagglutination in the sample zones following immobilisation of the antibodies directed at each Rh antigen. Detection of hormones in non-invasive body fluids Non-invasive fluids are defined as substances that exist out of the human body. These include human breast milk, saliva, perspiration, and urine. These fluids have also been used for monitoring blood sugar, diagnosing celiac disease, evaluating alteration in body fluids, measuring pH and sodium levels in saliva and sweat, determining body fluid dynamics, and more ( [150–152], etc.). A DNA aptamer-based sensor was developed [153] to identify dopamine in urine. Duplex aptamer dissociation served as the method’s foundation, in which dopamine in the urine caused the sensor to alter conformation and become released from the capture probe. Schonhorn et al. [154] created a sandwich immunoassay for the pregnancy biomarker (human chorionic gonadotropin) hCG detection in urine. The experiment involved a three-dimensional patterned piece of paper with unaltered and hydrophobic wax-printed sections. The detection limit for this colorimetric approach was 6.7 mIU/ml, and the detection range was 0–250 mIU/ml. Within 10 min, the test’s findings were ready. A unique molecularly imprinted polymer (MIP) grafted PAD for the sensing of 17-E2, which are essential for female menstrual and estrous cycles, was created by Xiao et al. [155] by using 12 mL of acetonitrile as the solvent, and using the molar ratios of 12:12:1 for the crosslinker, functional monomer, and template molecule. The detection limit for 17-estradiol in samples of human milk and urine using this method was determined to be 0.25 g/l. Detection of hormones in invasive body fluids These bodily fluids are the liquids that remain in the body. These consist of pleural fluids, blood plasma, blood serum, cerebrospinal fluid, and ascitic fluid [156]. Other applications of invasive body fluids include glucose monitoring [157], proteome analysis [158], the creation of wearable electrochemically active biosensors [159], the detection of antibodies [160], postmortem toxicology profiles, the diagnosis of Alzheimer’s disease using specific peptides [161], and the identification of biomarkers for various diseases. A device was created by Rattanarat et al. [162] to detect dopamine in serum samples using electrochemical paper that had been treated with sodium dodecyl sulfate. With a dynamic detection range of 1–100 uM and a detection limit of 0.37 M, this three-layer device was a simple, affordable technique. Shao et al. [163] created a low-cost kit for quick PCT detection because procalcitonin (PCT) is frequently utilized as a detector for bacterial infection. This approach was created for quick on-site detection with quick results by combining a double antibody sandwich immunofluorescent test with the traditional LFA. The WHO designated the onset of a novel coronavirus disease to be a public health emergency of global concern in January 2020. A general strategy to stop the spread of the COVID-19 outbreak is to isolate the infected individuals using efficient diagnostic techniques; the commonly used diagnosis technique currently in use is RT-PCR. Paper-based devices, as opposed to RT-PCR, are analytical tools that may perform rapid and accurate biomolecular detection without the need for laboratory-grade equipment or trained personnel. A low-cost and easily available serological technique to detect SARS-CoV-2 humanized antibodies was developed [164]. In this study, a common serological assay technique, ELISA, was combined with paper-based devices and the synthesized SARS-CoV-2 nucleocapsid antigen was deposited on the PAD. The recombinant antigen on the device might bind to the target antibodies in the human serum and create an immunological complex. It only took 30 min to complete the colorimetric reaction using the tetramethylbenzidine substrate and horseradish peroxidase (TMB/HRP), which is substantially faster than a typical ELISA experiment (usually 1 to 2 h). Yang et al. [165] suggested a possible RNA-based POC diagnostic tool for COVID-19 detection that integrates a paper-based POC diagnostic tool and LAMP assay technology. Nasal swabs can be used by home quarantine patients to collect their infected specimens. The colorimetric outcome of the LAMP reaction can then be seen on paper with the addition of certain reagents. The user could submit the output to cloud storage through the Internet by using a mobile phone camera to record the colorimetric shift. Using the Francisella novicida Cas9 enzyme [166], created a CRISPR-based diagnostic paper test strip for the detection of the N501Y mutation. This assay has the potential to be tailored to additional interesting mutations in addition to being able to identify SARS-CoV-2 infection with this mutation. Yakoh et al. [105] presented a paper-based electrochemical biosensor, outlining a label-free technique for S protein antigen detection. An origami platform was created using chromatography paper as the substrate, and carbon-based electrodes were printed on it. SARS-CoV-2 IgM was then immobilized at the working electrode that had been modified with graphene oxide for antigen binding. Additionally, paper microfluidics and ELISA tests were coupled to allow for the detection and quantification of multiplex antibodies from an individual health serum sample. Gong et al. [167] carried this out utilizing a porous material and wax fabrication method for printing. It executes all the necessary ELISA test phases as well as the instrument-free sampling and monitoring of serum samples. A paper-based biosensor with gold-hybridized zinc oxide nanowires (ZnO NWs) was presented [168], in which the working electrode was a critical component (WE). In less than 30 min, our biosensor could distinguish between IgG antibody concentrations against the SARS-CoV-2 spike glycoprotein S1 unit utilizing impedimetric signal variations. For the quick and accurate sensing of SARS-CoV-2 spike antigen, Liu et al. [169] created a novel lateral flow strip-integrated nanozyme and enzymatic chemiluminescence immunoassay-based chemiluminescence testing. The paper test is based on a potent Co-Fe@hemin-peroxidase nanozyme that catalyses chemiluminescence equivalent to native peroxidase HRP and boosts immune reaction signal. Detection of other biomarkers Monitoring of protein- and DNA-based indicator is one of the most rapidly expanding areas of research for POC detection. For the unique detection of active pharmacological components in antituberculosis (TB) medications, color bars were used [170]. Similar to this, Koesdjojo et al. [171] proposed a method for anti-malarial medication. To increase the enzymatic filtration of the HIV DNA tenfold in a short period of time, a PAD for the detection of HIV DNA was developed. Monitoring of protein- and DNA-based biomarkers is one of the most rapidly expanding areas of research for POC detection. The enzymatic preservation, element blending, and repressor polymerase amplification of HIV DNA processes are all combined on the paper by PAD. The Zika virus (ZIKV) was tested on a platform created [172] using RT-LAMP, and the entire procedure was carried out on a microfluidic chip made of wax-printed paper. The paper fibers in the device could pretreat large size molecules when a volume of blood serum or urine was introduced. Furthermore, proteins and other cell pieces were left behind due to the significant negative polarity of the cellulose fibers in paper, while the viral RNA with negative charges migrated to the end of the channel. On a straightforward hot plate, the target nucleic acids were amplified, and the results of the amplification can be determined by gauging the intensity of the pH indicator dye that was added. The most frequent infection that causes gastroenteritis in children, rotavirus A, has also been detected using LAMP-based paper devices [173]. It simply took 30 min to finish the thermal RNA amplification and nucleic acid extraction on a plain paper disc. Rotavirus A positive amplification result is instantly visible to the unaided eye as rose-red on the paper. Environmental monitoring Environmental deterioration has recently become the top worry for environmentalists. Ample resources, such as power and water, are needed for both home and industrial activities due to the continuously growing population and progress of the human race. The side products and leftovers of industrialization are released into the ambiance at the same time in the form of hazardous gases and effluents. Therefore, it is urgently necessary to control and regulate the toxins, particularly in the ambiance fluid. Nie et a. [67] presented the first instance of a paper-based sensor designed for the sensing of heavy metal in 2010. To move the sample through the device, they used screen-printed electrodes made from paper, on which microchannels were created using patterning methods. Mensah et al. [174] developed solid-contact ion-selective electrodes (SC-ISEs) based on a porous site to quantify Cd+2, Ag+, and K+. To accomplish the specificity for the ions, PAD was equipped with a membrane that contains ionic sites, and traditional ionophores for Cd+2, Ag+, and K+. Yu et al. [175] created a device based on the lamination approach to detect lead. A spatula was used to apply conductive electrodes to the paper after it had been cut out using a CO2 laser to seep the ink into the paper. The electrode layer of PAD was then positioned between two more paper layers that had been sandwiched together and layered with the biodegradable polyester polycaprolactone (PCL). The resulting laminated electrodes were then permanently put together to provide a durable and practical device. Wang et al. [176] created a paper-based multianalyte detection system in 2018 using nitrocellulose paper (0.45 m pore size). The three-electrode cell used in the paper-based electrodes was created using the magnetron sputtering technique, which spat a thin layer of gold onto the paper. PAD’s capabilities were initially tested for the purpose of detecting Cu+2, which was then used to refine the voltammetric parameters. Studying the interference from Pb+2, Cd+2, Zn+2, Bi+3, Cl, Na+, and K+ revealed that the Cu+2 signal decreased by up to 10 percent, reaching a value of 15 percent in the presence of Pb+2, while still demonstrating the device’s good performance. A separate methodology was proposed by Shimizu et al. [177] for quantification of phosphate over paper. The Murphy and Riley approach was used by the authors, and they took advantage of the P-Mo complex’s creation in a solution before introducing the analyte and the reagents to the paper electrode. It has been demonstrated that using this method enables simultaneous increases in the active regions and unhindered redox processes. For the monitoring of paraoxon-ethyl in soil and fertilized soil samples, Cioffi et al. [178] created an electrochemical biosensor based on office paper. The sample required 100 L of aqueous solution (2 percent ethanol) for the treatment, accompanied by a vortex and filtration with an MF-Millipore Membrane Filter. The bio detector was able to detect quantities of 10 and 25 ng/mL in soil with recovery values of 84 percent and 97 percent, respectively, based on a signal-to-noise ratio of 3 in standard solutions. A unique paper-based immunoassay was created for the accurate measurement of ethinyl estradiol (EE2) in water samples [179]. The silica nanoparticles were utilized to enhance the coating of biomolecule immobilization, enabling an improvement in their assimilation into the device and resulting in signal amplification. In order to capture and preconcentrate EE2, river water specimen were integrated to the amended layer of hydrophilic microzones as shown in Fig. 14. Paper microzones were then placed over the decreased graphene sheet on a carbon electrode that had been screen-printed. To desorbate the bound EE2, sulfuric acid solution was placed to the paper microzones. The recovered EE2 was electrochemically detected using square-wave voltammetry, and the oxidation current that resulted was comparable to the EE2 level in the sample.Fig. 14 Schematic diagram of the electrochemical paper-based immunocapture assay to determine the quantity of ethinylestradiol (EE2) in samples. a Paper microzones, b paper altered with anti-EE2 specific antibodies and silica nanoparticles (SNs) and then the addition of river water sample, c collect paper microzones to collect with the layer of reduced graphene on electrode d On the edge of reduced graphene, paper microzones were applied, e bound EE2 was dissolved by applying a weak acid solution to the paper, f electrochemical detection by square-wave voltammetry (SWV) A paper-based instrument was created to detect the presence of diclofenac (DCF) in samples of spiked tap water [180]. A circular design was initially wax printed on paper before being heated to 100∘C for one minute of curing. The reference and counter electrodes of the commercial connector were gold-plated pins spanning a piece of black plastic. The wires served as electrodes and a handy connection for the industrial interaction that was attached to the power supply unit. A clip was made by fusing the reference and counter electrodes together. By creating an 8 electrochemical cell framework for multiple observations, the idea’s adaptability was shown. Energy devices Paper is a desirable material for energy storage devices due to its availability, minimal cost, readily disposed of, and environmentally acceptable due to the nonhazardous waste they produce. The most often used paper-based energy components include capacitors, cells, transistors, power stations, detectors, RFID tags, solar panel arrays, digital displays, and medical surveillance systems. Guo et al. [181] proposed a paper-based self-charging power unit that combines a paper-based triboelectric nanogenerator and a supercapacitor, to simultaneously harvest and store energy from body movement. However, these devices need to scale up for the generation of power in large quantities. Below are some of the most recent developments in creating energy devices based on the idea of paper-based microfluidics: Batteries POC devices must meet the ASSURED criteria of the WHO and be self-powered, integrated with power-generating units, and should be used without the use of any additional equipment. Thom et al. [78] demonstrated the first microfluidic device that could produce its own electricity when a sample was added. The device possesses fluidic channels with fluidic batteries built right in. These batteries were fabricated by stacking the various layers of the paper, with the electrodes, electrolyte, and salt bridge loaded into the appropriate paper sheet in a dry state. Lee [79] created paper-based batteries by using copper as the current collector, magnesium foil for the anode, and filter paper coated with copper chloride for the cathode. A maximum voltage and power of 1.56 V and 15.6 mW were delivered by the battery when a sample of urine, salvia, or tap water was added. Paper-based batteries are appropriate for single-use ones since these batteries are activated upon the application of reagent, and the power output of batteries tends to decrease as reagent decays over time. Based on the idea of origami, Liu et al. [182] developed a self-powered ePAD that can detect glucose. The device integrates with a primary battery and can directly activate analyte solutions. A simple origami bacteria battery that can fold and unfold to accommodate various power requirements was proposed [183]. The device is filled with water or wastewater that has a very little amount of bacteria dissolved into it. As the liquid moves through the fluidic channels, it eventually reaches the batteries and produces electricity. Al-air battery is one of the great options among many various metal-air batteries available in the market. Shen et al. [184] integrated the idea of paper-based microfluidics with aluminum-air batteries in 2019 to eliminate the need for costly air electrodes or external pump devices. They sandwiched a piece of graphite foil coated with a catalyst between an anode made of aluminum foil and a cathode made of graphite foil. As shown in Fig. 15, an absorbent pad was also employed with a paper channel to ensure a uniform flow of electrolytes.Fig. 15 Schematic representation of an aluminum foil anode, a catalyst-coated graphite foil cathode, and a thin sheet of fibrous capillary paper are sandwiched in a paper-based Al-air battery Al-air battery on paper microfluidic channel demonstrates much-increased capacity when compared to traditional Al-air battery. A paper-based Al-air battery with a maximum power density of 21 mW/cm2 was also reported by Wang et al. [185]. One flexible zinc-air battery containing a brand-new hollow channel construction was described by Yang et al [186]. To lower the internal resistance of ZABs, one hollow channel structure was successfully constructed and incorporated. The maximum power density of the hollow channel-based ZAB was 138 mW/cm2, 283% greater than that of traditional P-ZABs. When the device was bent from 0∘ to 180∘, it was capable of controlling a calculator. Wang et al. [80] created a 5-cell battery with an efficiency of up to 97% after discovering that Al corrosion could be stopped in an alkaline environment using paper-based delivery. This battery pack was successfully scaled up and used to illustrate how to charge portable electronics. Fuel cells It is a device that generates electricity through a chemical process. In contrast to batteries, cells do not deplete or require a recharge. The identification and application of sustainable and environmentally friendly energy supplies are required due to the rapid increase in energy consumption. Applications for wind energy, photovoltaics, and other renewable energy sources are constrained by their low efficiency. As a more efficient means of converting a fuel’s chemical energy into electric power, fuel cells have emerged as a superior alternative for generating energy. These microfluidic fuel cells include chemical sensors in addition to being employed with communication and transportation systems. Zebda et al. [187] proposed an enzyme-based micro fuel cell in which electrodes were positioned along the catholyte and anolyte streams of the fuel and oxidant streams in the Y-direction. While glucose oxidase worked at the anode to oxidize glucose, laccase worked at the cathode to reduce O2. Noh and Shim [188] reported another enzymatic fuel cell by immobilizing enzyme (glucose oxidases) molecules to the electrode surface in order to further lower the cost and extend the life of the fuel cell up to 16 days. The power density and open circuit voltage produced by the conversion of glucose into gluconic acid and hydrogen peroxide are 0.78 mW cm2 and 0.48 V, respectively. Using graphite electrodes attached to conductive wires through silver adhesive paste on a Y-shaped filter paper strip, Arun et al. [189] created a capillarity-mediated fuel cell. Inlet channels were soaked in a solution of sulfuric acid (oxidant) and formic acid (fuel). Formic acid produced 32 mW cm2 of electricity for more than 15 h by utilizing 1 mL of fuel. On the anode, formic acid broke down into CO2 and electrons, which were then transmitted to the cathode by the external circuit. Based on the idea of reversed electrodialysis, Chang et al. created a multi-layered paper device for energy harvesting. This approach uses asymmetric ion transport through ion-selective membranes to extract energy from two solutions with varying salt contents. A voltage differential across the membrane is caused by the concentration difference, which generates electricity. Wax was used to define the flow, and the paper was coated with Ag/AgCl ink to create the electrodes. When a potassium chloride concentration gradient (0.1 mM/100 mM) was applied across the membrane of the device, which uses an ion-selective membrane placed between two layers of wax-printed paper, the device produced a power density of 275 nW cm2. In order to control the capillary flow on paper, Wang et al. [137] proposed coupling the microfluidic channel outputs with a photothermal module for water evaporation. As a proof of concept, prototype paper-based microfluidic fuel cells coupled to a photothermal module are created. Their peak power density can rise when exposed to simulated sunlight. The recent research opens a new avenue for controlling the functionality of PAD, a problem that has long existed in this field. It not only provides a realistic way to improve the efficiency of solar-powered paper-based microfluidic fuel cells. Food quality One of the essentials of life is food, and the nutritional content of the food is quite important for ensuring a healthy lifestyle. As a result, access to high-quality, safe foods is a must for human existence. Both physical and mental health can be maintained with food. Food safety has become one of the most critical challenges in the world due to the introduction of numerous chemical dangers to improve the flavor or aesthetic look of food, satisfy high market demand, and reduce costs. The issue of poor food quality is more serious in developing nations, especially in rural regions. Therefore, diagnosis technology must be affordable, portable, and small. The amounts of nitrite, a preservative used to give the meat a fresh appearance and extend shelf life were determined [190]. A wax stamping technique was used to create a paper-based microplate. The Griess reagents, which generate a pink color when reacting with nitrite ions in food, were then put in each microzone as colorimetric markers. The amount of nitrite present in the meat directly correlated with the intensity of the resulting pink color. By analyzing the coffee-ring effect of the produced colors on the well plates, Trofimchuk et al. [191] improved the limit of detection for a similar device. As low as 1.1 mg/kg was determined to be the detection limit of this test for nitrite in pork, demonstrating the potential uses of regularly checking the nitrite level in meat samples. For the colorimetric detection of amylose content in rice, Hu et al. [192] created PADs. Their suggested technique of detection was based on the interaction between amylose and iodine, which might result in an amylose-iodine complex with an obvious blue color. They demonstrated that this method may be used to evaluate rice products with an accuracy of 6.3% and amylose levels ranging from 1.5 to 26.4%. Nogueira et al. [193] used a redox titration technique to colorimetrically identify the alcohol concentration of whiskey samples on PADs. In this reaction, the amount of oxalic acid consumed during the back-titration was used to indirectly quantify the amount of ethanol in whiskey while taking the stoichiometric ratio into account. They have demonstrated that their suggested detection approach, which has a detection limit of 2.1% at the point of need, is affordable and only needs a tiny amount of reagent to precisely assess the concentration of ethanol in an alcoholic beverage. For the simultaneous spot test analysis of boric acid, maltodextrin, and hydrogen peroxide, Patari, and Mahapatra [194] designed a paper test card. Using a laser printer to print toner ink, hydrophobic channels with a 14 mm diameter were created on Whatman Grade 4 filter sheets. A camera was used to take pictures of the reaction zone to assess the color variation of the area. The reaction zone will turn orange, bluish chocolate, and brown depending on the presence of boric acid, maltodextrin, and H2O2. A μPAD the concurrent calorimetric measurement of urea, H2O2, and pH was published by Guinati et al. [195]. To ensure that the paper was completely cut without any surface damage, the EVA-coated polyester Gazela laminator model was used to laminate the paper at 140∘C. Then a layout of the ‘PAD’ was created to be cut out using a craft cutter printer, which can produce gadgets quickly, cheaply, and with a minimum amount of technical equipment. The software version was used to analyze the digital photographs after they had all been digitized at a resolution of 600 dpi. Despite the numerous benefits provided by paper-based devices, there is still much room for technology development. Colorimetric detection methods are commonly used in PADs, which makes getting quantitative results difficult. Furthermore, when it comes to PAD-based energy generation, the technology is semi-ready and needs to be scaled up. List of PADs successfully demonstrated for diverse applications The devices are small, light, portable, and cost little to manufacture, use, and dispose of. Low reagent and analyte consumption is a unique benefit of microfluidics. A wide range of practical applications has been found for them in a variety of research fields: chemistry, biochemistry, genomics, forensics, toxicology, immunology, environmental studies, and biomedicine. Microfluidics have been used successfully in the past in the clinical analysis of blood, the detection and identification of infections, proteins, and environmental toxins, genetic research, and in the pharmaceutical sector. The analytical and diagnostic capabilities of these simple devices may revolutionize medicine and pharmaceuticals. Therefore, providing a list of PADs (specifically for clinical and home applications) which has been successfully demonstrated at least at the laboratory level.Table 2 List of ‘μPADs’ Field-up application Short description Medical diagnosis Antibody screening tool that shows whether a patient has a contagious disease infection and an immune reaction to it [196] Medical diagnosis Devices used to identify uropathogenic E. coli rely on the ability to detect nitrite, which is produced when E. coli reduces nitrate. [197] Food quality control Pesticide detection sensor made of paper for crop samples [198] Food quality control 3D PAD for identifying the milk allergen casein [199] Food quality control Colorimetric PAD to detect Salmonella [200] Medical diagnosis A pop-up, DNA-based, label-free ePAD for HBV (a biomarker of liver disorders) detection [201] Medical diagnosis A vertical flow-based paper sandwich-type immunosensor for sensing of influenza H1N1 viruses [202] Food quality control Instrument to measure aluminium in water without pre-treatment or pre-concentration of the sample [203] Medical diagnosis PAD for detection of malaria [204] Medical diagnosis Device for medical diagnosis and sweat analysis that simultaneously measures glucose, lactate, pH, chloride, and volume [205] Medical diagnosis Platform for electrochemical immunosensing for pmol/L Ebola virus detection [206] Medical diagnosis Human chorionic gonadotropin (a pregnancy indicator) detection via a PAD [207] Medical diagnosis PAD to immobilize different antibodies or anti-immunoglobulin E onto screen-printed carbon electrodes [208] Medical diagnosis PAD for COVID-19 diagnosis [209–211] Medical diagnosis Biosensor for POC sensing of dengue virus [212] Food quality control PAD to track total ammonia in fish pond water [213] Medical Diagnosis Electrochemical and self-powered paper-based device for glucose sensing [214, 215] Medical diagnosis PAD for eliminating the necessity for a micropipette in quantitative analysis [216] Medical diagnosis PAD to extract blood plasma from a whole blood sample [138] Medical diagnosis A disposable ePAD for quantification of albumin in a urine sample [217] Food quality control 3D PAD to simultaneously detect multiple chemical adulterants in milk [195, 218] Medical diagnosis An intelligent paper-based UV monitor that can detect the solar UV intensity in real time for human health and safety [219] Food quality control For estimation of the peroxide value in vegetable oils using colorimetric PAD [220] Medical diagnosis Using exhaled air, an ePAD wearable sensor can detect hydrogen peroxide in real time [221] Food quality control Escherichia coli and Staphylococcus aureus, the two main pathogenic bacteria that cause milk poisoning, can be found using a colorimetric PAD [222] Medical diagnosis PAD for blood typing. [129, 147, 185] Medical diagnosis Detection of 17-E2, which is crucial for female menstrual and estrous cycles [155] Medical diagnosis Peptide-based Alzheimer’s diagnostic device [161] Energy generation A power unit that incorporates a paper-based supercapacitor and a triboelectric nanogenerator (TENG) to concurrently harvest and store energy from the movement [181] Food quality control Device to detect the presence of diclofenac (DCF) in samples of spiked tap water [179] Energy generation Paper-based batteries with maximum voltage and power of 1.56 V and 15.6 mW [78] Food quality control Device to detect the amount of nitrite, a preservative used in meat [190, 191] Food quality control Device based on redox titration technique to calorimetrically identify the alcohol concentration of whiskey samples [193] Limitations The outstanding qualities of paper-based microfluidic devices made them suitable for an endless number of applications. However, due to the characteristics of paper, fabrication processes, analytes chosen, and sensing techniques used in the devices, μPADs do have some limitations. In addition, major drawbacks of paper-based devices include sample retention in fluidic channels and significant sample evaporation during operation, both of which reduce device efficiency. The amount of sample needed increases because only about half of the entire introduced sample volume reaches the detecting zone. The effectiveness of some pattering techniques is greatly influenced by the environment in which the device will be used, and the effectiveness of some hydrophobic chemicals is insufficient to create robust hydrophobic barriers that can tolerate samples with different properties. When a liquid with low surface tension comes into contact with wax channels, the liquid starts to penetrate even in hydrophobic parts, whereas the hydrophobic channels or AKD only function properly for particular liquids with surface tension higher than a critical value. This phenomenon occurs as wax creates hydrophobicity by obstructing the pores of paper and lowering the surface energy of paper to effectively direct liquids. Without highly skilled and experienced people, comparison-based detection methods cannot produce accurate results. Various detection techniques are unable to pick up contamination in samples with low contamination levels. These are the present drawbacks of paper-based microfluidic technology that must be overcome. Conclusion Paper is meeting the optimum foundation material requirement for bringing this technology from the lab to the market due to the development of new fabrication protocols for PADs. Litmus paper is among the first papers to be used in chemical analysis. Despite being widely used, litmus paper was a revolutionary invention at the time because it made possible accurate pH measurements. Analytical devices began to be developed slowly with one of the most notable developments being the LFA, which was first industrialized as an over-the-counter pregnancy test in 1975 [223]. In 2007, Whitesides’ group published a paper that ignited the field [1]. The paper-based devices meet WHO specifications for diagnostic devices used in developing countries. According to WHO, the device should be ASSURED, that is, affordable, sensitive, specific, user-friendly, rapid and robust, equipment-free, and deliverable. Paper enables fluid flow without pumps, purication, electrode stabilization, and other applications. Paper devices can be equipment-free if consider integrated devices or colorimetric detection, with the exception of capillary forces that render external pumping obsolete. The devices are portable because the paper is thin, and it is also widely available worldwide. Consider that fully integrated, reusable, sensing platforms will soon be available as paper-based electronics advance. This review discusses the fabrication methods and detection modes in detail. We also discussed recent advances in μPAD for POC diagnostics, food quality control, power generation, and environmental control with theoretical analysis of fluid flow in paper. With minor changes to the device design and fabrication methods, PADs can be effectively implemented for the analysis of basic and extensive systems. There are several issues that remain despite advancements in paper-based microfluidic technology. Fabrication of μPADs requires the printing of hydrophilic paper by using methods like photolithography, screen printing, etc to control the flow of liquid in the appropriate manner. Although these patterning methods can efficiently define the flow in a porous substrate, various other fabrication techniques are also required for the successful mass production of these devices. Therefore, large-scale printing methods should be investigated to fabricate μPADs with multilayer complex structures that can be made at low cost, high resolution, and with easy process steps. It will be difficult to achieve the big goals discussed above. The field must continue to develop in the future, focusing on both basic and applied research areas while also considering the elements needed for industrialization. Materials science has a chance to contribute more to fundamental research by improving techniques for controlling the reactivity of devices using materials building and surface alteration. Although several papers manufactured from different natural or synthetic fibres have been created, PADs are still widely applied in biosensor applications. Fiber-based materials have mechanical stability, a hydrophobic interface, porosity, and the capacity to change the texture through interaction with biorecognition molecules. Some examples of these materials include Teflon, glass fibres, graphene and graphene oxide, polypropylene, poly(lactic acid), and carbon nanotubes. The ongoing exploration of hybrid devices that combine various materials and flow patterns and a detailed understanding of circulation in these systems will enable the creation of new systems from first principles instead of using a considerably slower empirical approach. It is critical from a translational perspective to keep broadening the PAD usage field with an emphasis on applications where PADs actually bring value that is unique from other technologies. By approaching it from this angle, you’ll be able to enter the marketplace more quickly and potentially effect real change. Abbreviations PAD Paper-based analytical device μPAD Microfluidic paper-based analytical device ePAD Electrochemical Paper-based analytical device PCAD Microfluidic paper-based chemiluminescence analytical device WHO World health organisation LOC Lab-on-chip LFA Lateral flow assay SPCE Screen-printed carbon electrodes PMMA Poly methyl methacrylate FLASH Fast lithographic activation of sheets PDMS Polydimethylsiloxane AKD Alkyl ketene dime LAMP Loop-mediated isothermal amplification RT-PCR Real-time reverse transcription–polymerase chain reaction RT–LAMP Reverse transcription loop–mediated isothermal amplification SARS-CoV Severe acute respiratory syndrome-associated coronavirus ELISA Enzyme-linked immunosorbent assay POC Point-of-care ==== Refs References 1. Martinez AW Phillips ST Butte MJ Whitesides GM Patterned paper as a platform for inexpensive, low-volume, portable bioassays Angew. Chem. 2007 119 8 1340 1342 2. A.W. Martinez, S.T. Phillips, G.M. Whitesides, E. Carrilho, Diagnostics for the developing world: microfluidic paper-based analytical devices (2010) 3. Tay A Pavesi A Yazdi SR Lim CT Warkiani ME Advances in microfluidics in combating infectious diseases Biotechnol. Adv. 2016 34 4 404 421 26854743 4. D. Mark, S. Haeberle, G. Roth, F.v. Stetten, R. Zengerle, Microfluidic lab-on-a-chip platforms: requirements, characteristics and applications. Microfluid. Based Microsyst. pp. 305–376 (2010) 5. B. Bhushan, in Springer handbook of nanotechnology (Springer, 2017), pp. 1–19 6. D. Lin, B. Li, J. Qi, X. Ji, S. Yang, W. Wang, L. Chen, Low cost fabrication of microfluidic paper-based analytical devices with water-based polyurethane acrylate and their application for bacterial detection. Sens. Actuators B: Chem. 303, 127,213 (2020) 7. Martinez AW Phillips ST Whitesides GM Three-dimensional microfluidic devices fabricated in layered paper and tape Proc. Natl. Acad. Sci. 2008 105 50 19606 19611 19064929 8. Martinez AW Phillips ST Wiley BJ Gupta M Whitesides GM Flash: a rapid method for prototyping paper-based microfluidic devices Lab Chip 2008 8 12 2146 2150 19023478 9. Carrilho E Phillips ST Vella SJ Martinez AW Whitesides GM Paper microzone plates Anal. Chem. 2009 81 15 5990 5998 19572563 10. Lu Y Shi W Jiang L Qin J Lin B Rapid prototyping of paper-based microfluidics with wax for low-cost, portable bioassay Electrophoresis 2009 30 9 1497 1500 19340829 11. He Y Wu Y Fu JZ Wu WB Fabrication of paper-based microfluidic analysis devices: A review RSC Adv. 2015 5 95 78109 78127 12. Yang Y Noviana E Nguyen MP Geiss BJ Dandy DS Henry CS based microfluidic devices: emerging themes and applications Anal. Chem. 2017 89 1 71 91 27936612 13. Songjaroen T Dungchai W Chailapakul O Laiwattanapaisal W Novel, simple and low-cost alternative method for fabrication of paper-based microfluidics by wax dipping Talanta 2011 85 5 2587 2593 21962687 14. Carrilho E Martinez AW Whitesides GM Understanding wax printing: a simple micropatterning process for paper-based microfluidics Anal. Chem. 2009 81 16 7091 7095 20337388 15. Mani V Kadimisetty K Malla S Joshi AA Rusling JF based electrochemiluminescent screening for genotoxic activity in the environment Environ. Sci. Technol. 2013 47 4 1937 1944 23331021 16. Kaewarsa P Laiwattanapaisal W Palasuwan A Palasuwan D A new paper-based analytical device for detection of glucose-6-phosphate dehydrogenase deficiency Talanta 2017 164 534 539 28107969 17. Yamada K Henares TG Suzuki K Citterio D Paper-based inkjet-printed microfluidic analytical devices Angew. Chem. Int. Ed. 2015 54 18 5294 5310 18. Abe K Suzuki K Citterio D Inkjet-printed microfluidic multianalyte chemical sensing paper Anal. Chem. 2008 80 18 6928 6934 18698798 19. Bai L Xie Z Wang W Yuan C Zhao Y Mu Z Zhong Q Gu Z Bio-inspired vapor-responsive colloidal photonic crystal patterns by inkjet printing ACS Nano 2014 8 11 11094 11100 25300045 20. Maejima K Tomikawa S Suzuki K Citterio D Inkjet printing: an integrated and green chemical approach to microfluidic paper-based analytical devices RSC Adv. 2013 3 24 9258 9263 21. Maattanen A Ihalainen P Pulkkinen P Wang S Tenhu H Peltonen J Inkjet-printed gold electrodes on paper: characterization and functionalization ACS Appl. Mater. Interfaces. 2012 4 2 955 964 22233965 22. Mani V Paleja B Larbi K Kumar P Tay JA Siew JY Inci F Wang S Chee C Wang YT Microchip-based ultrafast serodiagnostic assay for tuberculosis Sci. Rep. 2016 6 1 1 11 28442746 23. Renault C Li X Fosdick SE Crooks RM Hollow-channel paper analytical devices Anal. Chem. 2013 85 16 7976 7979 23931456 24. Chitnis G Ding Z Chang CL Savran CA Ziaie B Laser-treated hydrophobic paper: an inexpensive microfluidic platform Lab Chip 2011 11 6 1161 1165 21264372 25. Das S Bhatia R based microfluidic devices: fabrication, detection, and significant applications in various fields Rev. Anal. Chem. 2022 41 1 112 136 26. Bruzewicz DA Reches M Whitesides GM Low-cost printing of poly (dimethylsiloxane) barriers to define microchannels in paper Anal. Chem. 2008 80 9 3387 3392 18333627 27. Faustino V Catarino SO Lima R Minas G Biomedical microfluidic devices by using low-cost fabrication techniques: a review J. Biomech. 2016 49 11 2280 2292 26671220 28. Amin R Ghaderinezhad F Bridge C Temirel M Jones S Toloueinia P Tasoglu S Pushing the limits of spatial assay resolution for paper-based microfluidics using low-cost and high-throughput pen plotter approach Micromachines 2020 11 6 611 32599882 29. Olkkonen J Lehtinen K Erho T Flexographically printed fluidic structures in paper Anal. Chem. 2010 82 24 10246 10250 21090744 30. P. de Tarso Garcia, T.M.G. Cardoso, C.D. Garcia, E. Carrilho, W.K.T. Coltro, A handheld stamping process to fabricate microfluidic paper-based analytical devices with chemically modified surface for clinical assays. Rsc Adv. 4(71), 37,637–37,644 (2014) 31. Akyazi T Saez J Elizalde J Benito-Lopez F Fluidic flow delay by ionogel passive pumps in microfluidic paper-based analytical devices Sens. Actuators, B Chem. 2016 233 402 408 32. Curto VF Lopez-Ruiz N Capitan-Vallvey LF Palma AJ Benito-Lopez F Diamond D Fast prototyping of paper-based microfluidic devices by contact stamping using indelible ink RSC Adv. 2013 3 41 18811 18816 33. Sameenoi Y Nongkai PN Nouanthavong S Henry CS Nacapricha D One-step polymer screen-printing for microfluidic paper-based analytical device (μpad) fabrication Analyst 2014 139 24 6580 6588 25360590 34. Li X Tian J Nguyen T Shen W based microfluidic devices by plasma treatment Anal. Chem. 2008 80 23 9131 9134 19551982 35. Chunfang Y Siyang Y Yan J Qiaohong H Hengwu C Fabrication of paper-based microfluidic devices by plasma treatment and its application in glucose determination Acta Chim. Sinica 2014 72 10 1099 1104 36. Jiang Y Hao Z He Q Chen H A simple method for fabrication of microfluidic paper-based analytical devices and on-device fluid control with a portable corona generator RSC Adv. 2016 6 4 2888 2894 37. Kao PK Hsu CC One-step rapid fabrication of paper-based microfluidic devices using fluorocarbon plasma polymerization Microfluid. Nanofluid. 2014 16 5 811 818 38. Kwong P Gupta M Vapor phase deposition of functional polymers onto paper-based microfluidic devices for advanced unit operations Anal. Chem. 2012 84 22 10129 10135 23113699 39. Demirel G Babur E Vapor-phase deposition of polymers as a simple and versatile technique to generate paper-based microfluidic platforms for bioassay applications Analyst 2014 139 10 2326 2331 24699534 40. Chen B Kwong P Gupta M Patterned fluoropolymer barriers for containment of organic solvents within paper-based microfluidic devices ACS applied materials & interfaces 2013 5 23 12701 12707 24283374 41. Jiang Y Study on fabrication of microfluidic paper-based analytical devices and manipulation of microfluidic flow in paper-based channels using a hand-held corona treater 2014 HangZhou, China ZheJiang University 42. Martinez AW Phillips ST Nie Z Cheng CM Carrilho E Wiley BJ Whitesides GM Programmable diagnostic devices made from paper and tape Lab Chip 2010 10 19 2499 2504 20672179 43. Kauffman P Fu E Lutz B Yager P Visualization and measurement of flow in two-dimensional paper networks Lab Chip 2010 10 19 2614 2617 20676410 44. Fu E Lutz B Kauffman P Yager P Controlled reagent transport in disposable 2d paper networks Lab Chip 2010 10 7 918 920 20300678 45. Tian J Kannangara D Li X Shen W Capillary driven low-cost v-groove microfluidic device with high sample transport efficiency Lab Chip 2010 10 17 2258 2264 20589291 46. Toley BJ McKenzie B Liang T Buser JR Yager P Fu E Tunable-delay shunts for paper microfluidic devices Anal. Chem. 2013 85 23 11545 11552 24245747 47. Houghtaling J Liang T Thiessen G Fu E Dissolvable bridges for manipulating fluid volumes in paper networks Anal. Chem. 2013 85 23 11201 11204 24228812 48. Jahanshahi-Anbuhi S Henry A Leung V Sicard C Pennings K Pelton R Brennan JD Filipe CD based microfluidics with an erodible polymeric bridge giving controlled release and timed flow shutoff Lab Chip 2014 14 1 229 236 24195917 49. Fu E Ramsey SA Kauffman P Lutz B Yager P Transport in two-dimensional paper networks Microfluid. Nanofluid. 2011 10 1 29 35 22140373 50. Lutz BR Trinh P Ball C Fu E Yager P Two-dimensional paper networks: programmable fluidic disconnects for multi-step processes in shaped paper Lab Chip 2011 11 24 4274 4278 22037591 51. Apilux A Ukita Y Chikae M Chailapakul O Takamura Y Development of automated paper-based devices for sequential multistep sandwich enzyme-linked immunosorbent assays using inkjet printing Lab Chip 2013 13 1 126 135 23165591 52. Li X Zwanenburg P Liu X Magnetic timing valves for fluid control in paper-based microfluidics Lab Chip 2013 13 13 2609 2614 23584207 53. Fridley GE Le H Yager P Highly sensitive immunoassay based on controlled rehydration of patterned reagents in a 2-dimensional paper network Anal. Chem. 2014 86 13 6447 6453 24882058 54. Anderson CE Huynh T Gasperino DJ Alonzo LF Cantera JL Harston SP Hsieh HV Marzan R McGuire SK Williford JR Automated liquid handling robot for rapid lateral flow assay development Anal. Bioanal. Chem. 2022 414 8 2607 2618 35091761 55. Glavan AC Martinez RV Maxwell EJ Subramaniam AB Nunes RM Soh S Whitesides GM Rapid fabrication of pressure-driven open-channel microfluidic devices in omniphobic rf paper Lab Chip 2013 13 15 2922 2930 23719764 56. Liu W Cassano CL Xu X Fan ZH Laminated paper-based analytical devices (lpad) with origami-enabled chemiluminescence immunoassay for cotinine detection in mouse serum Anal. Chem. 2013 85 21 10270 10276 24117197 57. E.I. Newsham, E.A. Phillips, H. Ma, M.M. Chang, S.T. Wereley, J.C. Linnes, Characterization of wax valving and μpiv analysis of microscale flow in paper-fluidic devices for improved modeling and design. Lab on a Chip (2022) 58. Q. Li, Y. Xu, J. Qi, X. Zheng, S. Liu, D. Lin, L. Zhang, P. Liu, B. Li, L. Chen, A self-powered rotating paper-based analytical device for sensing of thrombin. Sensors and Actuators B: Chemical 351, 130,917 (2022) 59. Dungchai W Chailapakul O Henry CS Electrochemical detection for paper-based microfluidics Anal. Chem. 2009 81 14 5821 5826 19485415 60. Apilux A Dungchai W Siangproh W Praphairaksit N Henry CS Chailapakul O Lab-on-paper with dual electrochemical/colorimetric detection for simultaneous determination of gold and iron Anal. Chem. 2010 82 5 1727 1732 20121066 61. Jagadeesan KK Kumar S Sumana G Application of conducting paper for selective detection of troponin Electrochem. Commun. 2012 20 71 74 62. Wu Y Xue P Kang Y Hui KM based microfluidic electrochemical immunodevice integrated with nanobioprobes onto graphene film for ultrasensitive multiplexed detection of cancer biomarkers Anal. Chem. 2013 85 18 8661 8668 23937646 63. Sekar NC Shaegh SAM Ng SH Ge L Tan SN A paper-based amperometric glucose biosensor developed with prussian blue-modified screen-printed electrodes Sens. Actuators, B Chem. 2014 204 414 420 64. Renault C Anderson MJ Crooks RM Electrochemistry in hollow-channel paper analytical devices J. Am. Chem. Soc. 2014 136 12 4616 4623 24635569 65. Dossi N Toniolo R Pizzariello A Carrilho E Piccin E Battiston S Bontempelli G An electrochemical gas sensor based on paper supported room temperature ionic liquids Lab Chip 2012 12 1 153 158 22076475 66. Cunningham JC Brenes NJ Crooks RM Paper electrochemical device for detection of dna and thrombin by target-induced conformational switching Anal. Chem. 2014 86 12 6166 6170 24871788 67. Nie Z Nijhuis CA Gong J Chen X Kumachev A Martinez AW Narovlyansky M Whitesides GM Electrochemical sensing in paper-based microfluidic devices Lab Chip 2010 10 4 477 483 20126688 68. Santhiago M Wydallis JB Kubota LT Henry CS Construction and electrochemical characterization of microelectrodes for improved sensitivity in paper-based analytical devices Anal. Chem. 2013 85 10 5233 5239 23581428 69. Godino N Gorkin R Bourke K Ducree J Fabricating electrodes for amperometric detection in hybrid paper/polymer lab-on-a-chip devices Lab Chip 2012 12 18 3281 3284 22842728 70. Santhiago M Kubota LT A new approach for paper-based analytical devices with electrochemical detection based on graphite pencil electrodes Sens. Actuators, B Chem. 2013 177 224 230 71. Dossi N Toniolo R Impellizzieri F Bontempelli G Doped pencil leads for drawing modified electrodes on paper-based electrochemical devices J. Electroanal. Chem. 2014 722 90 94 72. Ciniciato GP Lau C Cochrane A Sibbett SS Gonzalez ER Atanassov P Development of paper based electrodes: From air-breathing to paintable enzymatic cathodes Electrochim. Acta 2012 82 208 213 73. Shiroma LY Santhiago M Gobbi AL Kubota LT Separation and electrochemical detection of paracetamol and 4-aminophenol in a paper-based microfluidic device Anal. Chim. Acta 2012 725 44 50 22502610 74. Fosdick SE Anderson MJ Renault C DeGregory PR Loussaert JA Crooks RM Wire, mesh, and fiber electrodes for paper-based electroanalytical devices Anal. Chem. 2014 86 7 3659 3666 24625315 75. Yang J Nam YG Lee SK Kim CS Koo YM Chang WJ Gunasekaran S fluidic electrochemical biosensing platform with enzyme paper and enzymeless electrodes Sens. Actuators, B Chem. 2014 203 44 53 76. Lu J Ge S Ge L Yan M Yu J Electrochemical dna sensor based on three-dimensional folding paper device for specific and sensitive point-of-care testing Electrochim. Acta 2012 80 334 341 77. Ge S Ge L Yan M Song X Yu J Huang J A disposable paper-based electrochemical sensor with an addressable electrode array for cancer screening Chem. Commun. 2012 48 75 9397 9399 78. Thom NK Yeung K Pillion MB Phillips ST “fluidic batteries” as low-cost sources of power in paper-based microfluidic devices Lab Chip 2012 12 10 1768 1770 22450846 79. Lee KB Urine-activated paper batteries for biosystems J. Micromech. Microeng. 2005 15 9 S210 80. Y. Wang, W. Pan, H.Y. Kwok, H. Zhang, X. Lu, D.Y. Leung, Liquid-free al-air batteries with paper-based gel electrolyte: a green energy technology for portable electronics. Journal of Power Sources 437, 226,896 (2019) 81. C. Zhao, M.M. Thuo, X. Liu, A microfluidic paper-based electrochemical biosensor array for multiplexed detection of metabolic biomarkers. Science and technology of advanced materials 14(5), 054,402 (2013) 82. Ramfos I Vassiliadis N Blionas S Efstathiou K Fragoso A O’Sullivan CK Birbas A A compact hybrid-multiplexed potentiostat for real-time electrochemical biosensing applications Biosens. Bioelectron. 2013 47 482 489 23624017 83. Liu C Gomez FA A microfluidic paper-based device to assess acetylcholinesterase activity Electrophoresis 2017 38 7 1002 1006 28008633 84. Cardoso TM Channon RB Adkins JA Talhavini M Coltro WK Henry CS A paper-based colorimetric spot test for the identification of adulterated whiskeys Chem. Commun. 2017 53 56 7957 7960 85. Gabriel EFM Garcia PT Lopes FM Coltro WKT Based colorimetric biosensor for tear glucose measurements Micromachines 2017 8 4 104 86. Cardoso TM de Souza FR Garcia PT Rabelo D Henry CS Coltro WK Versatile fabrication of paper-based microfluidic devices with high chemical resistance using scholar glue and magnetic masks Anal. Chim. Acta 2017 974 63 68 28535882 87. Meelapsom R Jarujamrus P Amatatongchai M Chairam S Kulsing C Shen W Chromatic analysis by monitoring unmodified silver nanoparticles reduction on double layer microfluidic paper-based analytical devices for selective and sensitive determination of mercury (ii) Talanta 2016 155 193 201 27216673 88. Yamada K Suzuki K Citterio D Text-displaying colorimetric paper-based analytical device Acs Sensors 2017 2 8 1247 1254 28809488 89. Mujawar LH Dhavamani J El-Shahawi MS A versatile optical assay plate fabricated from e-waste and its application towards rapid determination of fe 3+ ions in water New J. Chem. 2017 41 18 9731 9740 90. Chowdury MA Walji N Mahmud MA MacDonald BD based microfluidic device with a gold nanosensor to detect arsenic contamination of groundwater in bangladesh Micromachines 2017 8 3 71 91. Liu CC Wang YN Fu LM Yang DY Rapid integrated microfluidic paper-based system for sulfur dioxide detection Chem. Eng. J. 2017 316 790 796 92. Carneiro MC Rodrigues LR Moreira FT Sales MGF Colorimetric paper-based sensors against cancer biomarkers Sensors 2022 22 9 3221 35590912 93. T. Mahmoudi, A.P. Tazehkand, M. Pourhassan-Moghaddam, M. Alizadeh-Ghodsi, L. Ding, B. Baradaran, S.R. Bazaz, D. Jin, M.E. Warkiani, Pcr-free paper-based nanobiosensing platform for visual detection of telomerase activity via gold enhancement. Microchemical Journal 154, 104,594 (2020) 94. Fu AC Hu Y Zhao ZH Su R Song Y Zhu D Functionalized paper microzone plate for colorimetry and up-conversion fluorescence dual-mode detection of telomerase based on elongation and capturing amplification Sens. Actuators, B Chem. 2018 259 642 649 95. W. Fernando, H. Jayarathna, M. Kaumal, Low-cost microfluidic electrochemical paper-based device to detect glucose. Journal of Science of the University of Kelaniya Sri Lanka 15(1) (2022) 96. Fonseca WT Castro KR de Oliveira TR Faria RC Disposable and flexible electrochemical paper-based analytical devices using low-cost conductive ink Electroanalysis 2021 33 6 1520 1527 97. Tomei MR Cinti S Interino N Manovella V Moscone D Arduini F based electroanalytical strip for user-friendly blood glutathione detection Sens. Actuators, B Chem. 2019 294 291 297 98. Ruecha N Shin K Chailapakul O Rodthongkum N Label-free paper-based electrochemical impedance immunosensor for human interferon gamma detection Sens. Actuators, B Chem. 2019 279 298 304 99. Wang H Zhou C Sun X Jian Y Kong Q Cui K Ge S Yu J Polyhedral-aupd nanoparticles-based dual-mode cytosensor with turn on enable signal for highly sensitive cell evalution on lab-on-paper device Biosens. Bioelectron. 2018 117 651 658 30005386 100. Moazeni M Karimzadeh F Kermanpur A Peptide modified paper based impedimetric immunoassay with nanocomposite electrodes as a point-of-care testing of alpha-fetoprotein in human serum Biosens. Bioelectron. 2018 117 748 757 30029196 101. J. Qi, B. Li, N. Zhou, X. Wang, D. Deng, L. Luo, L. Chen, The strategy of antibody-free biomarker analysis by in-situ synthesized molecularly imprinted polymers on movable valve paper-based device. Biosensors and Bioelectronics 142, 111,533 (2019) 102. He T Li J Liu L Ge S Yan M Liu H Yu J Origami-based “book” shaped three-dimensional electrochemical paper microdevice for sample-to-answer detection of pathogens RSC Adv. 2020 10 43 25808 25816 35518615 103. Santhiago M Henry CS Kubota LT Low cost, simple three dimensional electrochemical paper-based analytical device for determination of p-nitrophenol Electrochim. Acta 2014 130 771 777 104. S. Boonkaew, I. Jang, E. Noviana, W. Siangproh, O. Chailapakul, C.S. Henry, Electrochemical paper-based analytical device for multiplexed, point-of-care detection of cardiovascular disease biomarkers. Sensors and Actuators B: Chemical 330, 129,336 (2021) 105. Yakoh A Chaiyo S Siangproh W Chailapakul O 3d capillary-driven paper-based sequential microfluidic device for electrochemical sensing applications ACS sensors 2019 4 5 1211 1221 30969113 106. L. Wang, B. Li, J. Wang, J. Qi, J. Li, J. Ma, L. Chen, A rotary multi-positioned cloth/paper hybrid microfluidic device for simultaneous fluorescence sensing of mercury and lead ions by using ion imprinted technologies. Journal of Hazardous Materials 428, 128,165 (2022) 107. Y. Zhu, X. Tong, Q. Wei, G. Cai, Y. Cao, C. Tong, S. Shi, F. Wang, 3d origami paper-based ratiometric fluorescent microfluidic device for visual point-of-care detection of alkaline phosphatase and butyrylcholinesterase. Biosensors and Bioelectronics 196, 113,691 (2022) 108. Shi L Li L Li X Zhang G Zhang Y Dong C Shuang S Excitation-independent yellow-fluorescent nitrogen-doped carbon nanodots for biological imaging and paper-based sensing Sens. Actuators, B Chem. 2017 251 234 241 109. Zong L Xie Y Li Q Li Z A new red fluorescent probe for hg2+ based on naphthalene diimide and its application in living cells, reversibility on strip papers Sens. Actuators, B Chem. 2017 238 735 743 110. Liu C Ning D Zhang C Liu Z Zhang R Zhao J Zhao T Liu B Zhang Z Dual-colored carbon dot ratiometric fluorescent test paper based on a specific spectral energy transfer for semiquantitative assay of copper ions ACS Applied Materials & Interfaces 2017 9 22 18897 18903 28516780 111. Nuchtavorn N Macka M A novel highly flexible, simple, rapid and low-cost fabrication tool for paper-based microfluidic devices (μpads) using technical drawing pens and in-house formulated aqueous inks Anal. Chim. Acta 2016 919 70 77 27086101 112. Yu J Ge L Huang J Wang S Ge S Microfluidic paper-based chemiluminescence biosensor for simultaneous determination of glucose and uric acid Lab Chip 2011 11 7 1286 1291 21243159 113. Yu J Wang S Ge L Ge S A novel chemiluminescence paper microfluidic biosensor based on enzymatic reaction for uric acid determination Biosens. Bioelectron. 2011 26 7 3284 3289 21257303 114. I. Al Yahyai, H.A. Al-Lawati, J. Hassanzadeh, Carbon dots-modified paper-based chemiluminescence device for rapid determination of mercury (ii) in cosmetics. Luminescence (2022) 115. Zangheri M Cevenini L Anfossi L Baggiani C Simoni P Di Nardo F Roda A A simple and compact smartphone accessory for quantitative chemiluminescence-based lateral flow immunoassay for salivary cortisol detection Biosens. Bioelectron. 2015 64 63 68 25194797 116. Yetisen AK Akram MS Lowe CR based microfluidic point-of-care diagnostic devices Lab Chip 2013 13 12 2210 2251 23652632 117. Delaney JL Hogan CF Tian J Shen W Electrogenerated chemiluminescence detection in paper-based microfluidic sensors Anal. Chem. 2011 83 4 1300 1306 21247195 118. Wu L Ma C Zheng X Liu H Yu J based electrochemiluminescence origami device for protein detection using assembled cascade dna-carbon dots nanotags based on rolling circle amplification Biosens. Bioelectron. 2015 68 413 420 25618373 119. Ge L Yan J Song X Yan M Ge S Yu J Three-dimensional paper-based electrochemiluminescence immunodevice for multiplexed measurement of biomarkers and point-of-care testing Biomaterials 2012 33 4 1024 1031 22074665 120. Yan J Ge L Song X Yan M Ge S Yu J Paper-based electrochemiluminescent 3d immunodevice for lab-on-paper, specific, and sensitive point-of-care testing Chemistry-A European Journal 2012 18 16 4938 4945 22392821 121. Cai J Jin T Kou J Zou S Xiao J Meng Q Lucas-washburn equation-based modeling of capillary-driven flow in porous systems Langmuir 2021 37 5 1623 1636 33512167 122. Ponomarenko A Quéré D Clanet C A universal law for capillary rise in corners J. Fluid Mech. 2011 666 146 154 123. Fries N Dreyer M An analytic solution of capillary rise restrained by gravity J. Colloid Interface Sci. 2008 320 1 259 263 18255086 124. Patari S Mahapatra PS Liquid wicking in a paper strip: An experimental and numerical study ACS Omega 2020 5 36 22931 22939 32954142 125. S. Bhattacharya, S. Kumar, A.K. Agarwal, Paper microfluidics (Springer, 2019) 126. Wang Y Ye D Zhu X Yang Y Qin C Chen R Liao Q Spontaneous imbibition in paper-based microfluidic devices: Experiments and numerical simulations Langmuir 2022 38 8 2677 2685 35168321 127. Masoodi R Tan H Pillai KM Darcy’s law-based numerical simulation for modeling 3d liquid absorption into porous wicks AIChE J. 2011 57 5 1132 1143 128. Liu Z Hu J Zhao Y Qu Z Xu F Experimental and numerical studies on liquid wicking into filter papers for paper-based diagnostics Appl. Therm. Eng. 2015 88 280 287 129. T. Ouyang, J. Lu, P. Xu, X. Hu, J. Chen, Mechanism study and evaluation of high efficiency paper-based microfluidic fuel cell coupled with capillary force. Journal of Power Sources 520, 230,807 (2022) 130. S. Modha, Control and modeling of imbibition in paper-based microfluidic devices. Ph.D. thesis, University of California, Riverside (2022) 131. Elizalde E Urteaga R Berli CL Rational design of capillary-driven flows for paper-based microfluidics Lab Chip 2015 15 10 2173 2180 25813247 132. J. Songok, M. Toivakka, Modelling of capillary-driven flow for closed paper-based microfluidic channels. Journal of Micromechanics and Microengineering 27(6), 065,001 (2017) 133. Rosenfeld T Bercovici M 1000-fold sample focusing on paper-based microfluidic devices Lab Chip 2014 14 23 4465 4474 25256832 134. Dushin V Smirnov N Nikitin V Skryleva E Weisman YG Multiple capillary-driven imbibition of a porous medium under microgravity conditions: Experimental investigation and mathematical modeling Acta Astronaut. 2022 193 572 578 135. P.A. More, P.V. Tandel, Study of parametric effect on saturation rate in imbibition phenomenon for various porous materials. Journal of Ocean Engineering and Science (2022) 136. Q. Meng, L. Zhao, P. Li, F. Yang, J. Cai, Experiments and phase-field simulation of counter-current imbibition in porous media with different pore structure. Journal of Hydrology 608, 127,670 (2022) 137. W. Wang, L.L. Shen, H. Yu, W. Xu, J. Wang, C. Yong, G.R. Zhang, D. Mei, Solar-boosted paper-based microfluidic fuel cells for miniaturized power sources. Advanced Materials Technologies p. 2200154 (2022) 138. Songjaroen T Dungchai W Chailapakul O Henry CS Laiwattanapaisal W Blood separation on microfluidic paper-based analytical devices Lab Chip 2012 12 18 3392 3398 22782449 139. Noiphung J Songjaroen T Dungchai W Henry CS Chailapakul O Laiwattanapaisal W Electrochemical detection of glucose from whole blood using paper-based microfluidic devices Anal. Chim. Acta 2013 788 39 45 23845479 140. Yang X Forouzan O Brown TP Shevkoplyas SS Integrated separation of blood plasma from whole blood for microfluidic paper-based analytical devices Lab Chip 2012 12 2 274 280 22094609 141. Kar S Maiti TK Chakraborty S Capillarity-driven blood plasma separation on paper-based devices Analyst 2015 140 19 6473 6476 26270006 142. Kim D Kim S Kim S An innovative blood plasma separation method for a paper-based analytical device using chitosan functionalization Analyst 2020 145 16 5491 5499 32597456 143. Burgos-Flórez F Rodríguez A Cervera E De Ávila M Sanjuán M Villalba PJ Microfluidic paper-based blood plasma separation device as a potential tool for timely detection of protein biomarkers Micromachines 2022 13 5 706 35630172 144. G. Daniels, I. Bromilow, Essential guide to blood groups (John Wiley & Sons, 2011) 145. Proverbio D Spada E Baggiani L Perego R Assessment of a gel column technique for feline blood typing Vet. Res. Commun. 2009 33 1 201 203 19578954 146. Ota M Fukushima H Yonemura I Hasekura H Detection of ab0 blood group-active glycolipids extracted from red cell membrane and heat hematoma using tlc-immunostaining Z. Rechtsmed. 1988 100 2 215 221 3051781 147. Khan MS Thouas G Shen W Whyte G Garnier G Paper diagnostic for instantaneous blood typing Anal. Chem. 2010 82 10 4158 4164 20415489 148. Jarujamrus P Tian J Li X Siripinyanond A Shiowatana J Shen W Mechanisms of red blood cells agglutination in antibody-treated paper Analyst 2012 137 9 2205 2210 22433943 149. N. Larpant, W. Niamsi, J. Noiphung, W. Chanakiat, T. Sakuldamrongpanich, V. Kittichai, T. Tongloy, S. Chuwongin, S. Boonsang, W. Laiwattanapaisal, Simultaneous phenotyping of five rh red blood cell antigens on a paper-based analytical device combined with deep learning for rapid and accurate interpretation. Analytica Chimica Acta 1207, 339,807 (2022) 150. Pasinszki T Krebsz M Biosensors for non-invasive detection of celiac disease biomarkers in body fluids Biosensors 2018 8 2 55 29914179 151. Kouw PM de Vries PM Donker AJ Non-invasive measurement of body fluid dynamics Int. Yearb. Nephrol. 1992 1993 333 351 152. Olthof C De Vries P Kouw P Oe P Schneider H De Lange J Donker A Non-invasive conductivity method for detection of dynamic body fluid changes: in vitro and in vivo validation Nephrol. Dial. Transplant. 1993 8 1 41 46 8381934 153. S. Dalirirad, A.J. Steckl, Lateral flow assay using aptamer-based sensing for on-site detection of dopamine in urine. Analytical biochemistry 596, 113,637 (2020) 154. Schonhorn JE Fernandes SC Rajaratnam A Deraney RN Rolland JP Mace CR A device architecture for three-dimensional, patterned paper immunoassays Lab Chip 2014 14 24 4653 4658 25300302 155. Xiao L Zhang Z Wu C Han L Zhang H Molecularly imprinted polymer grafted paper-based method for the detection of 17β-estradiol Food Chem. 2017 221 82 86 27979279 156. Bauça JM Martínez-Morillo E Diamandis EP Peptidomics of urine and other biofluids for cancer diagnostics Clin. Chem. 2014 60 8 1052 1061 24212086 157. Beaucamp A Culebras M Collins MN Sustainable mesoporous carbon nanostructures derived from lignin for early detection of glucose Green Chem. 2021 23 15 5696 5705 158. Hu S Loo JA Wong DT Human body fluid proteome analysis Proteomics 2006 6 23 6326 6353 17083142 159. Pérez D Orozco J Wearable electrochemical biosensors to measure biomarkers with complex blood-to-sweat partition such as proteins and hormones Microchim. Acta 2022 189 3 1 28 160. J.M. Bhagu, Probing the in-situ conformation of monoclonal antibodies at hydrophobic interfaces using nmr spectroscopy. Ph.D. thesis, Florida Agricultural and Mechanical University (2021) 161. Veerabhadrappa B Delaby C Hirtz C Vialaret J Alcolea D Lleó A Fortea J Santosh MS Choubey S Lehmann S Detection of amyloid beta peptides in body fluids for the diagnosis of alzheimer’s disease: Where do we stand? Crit. Rev. Clin. Lab. Sci. 2020 57 2 99 113 31661652 162. Rattanarat P Dungchai W Siangproh W Chailapakul O Henry CS Sodium dodecyl sulfate-modified electrochemical paper-based analytical device for determination of dopamine levels in biological samples Anal. Chim. Acta 2012 744 1 7 22935367 163. Shao XY Wang CR Xie CM Wang XG Liang RL Xu WW Rapid and sensitive lateral flow immunoassay method for procalcitonin (pct) based on time-resolved immunochromatography Sensors 2017 17 3 480 28264502 164. Kasetsirikul S Umer M Soda N Sreejith KR Shiddiky MJ Nguyen NT Detection of the sars-cov-2 humanized antibody with paper-based elisa Analyst 2020 145 23 7680 7686 32975254 165. T. Yang, Y.C. Wang, C.F. Shen, C.M. Cheng. Point-of-care rna-based diagnostic device for covid-19 (2020) 166. M. Kumar, S. Gulati, A.H. Ansari, R. Phutela, S. Acharya, M. Azhar, J. Murthy, P. Kathpalia, A. Kanakan, R. Maurya, et al., Fncas9-based crispr diagnostic for rapid and accurate detection of major sars-cov-2 variants on a paper strip. Elife 10, e67,130 (2021) 167. F. Gong, H.x. Wei, J. Qi, H. Ma, L. Liu, J. Weng, X. Zheng, Q. Li, D. Zhao, H. Fang, et al., Pulling-force spinning top for serum separation combined with paper-based microfluidic devices in covid-19 elisa diagnosis. ACS sensors 6(7), 2709–2719 (2021) 168. Y. Ming, S. Hao, F. Wang, Y.R. Lewis-Israeli, B.D. Volmert, Z. Xu, A. Goestenkors, A. Aguirre, C. Zhou, Longitudinal morphological and functional characterization of human heart organoids using optical coherence tomography. Biosensors and Bioelectronics 207, 114,136 (2022) 169. D. Liu, C. Ju, C. Han, R. Shi, X. Chen, D. Duan, J. Yan, X. Yan, Nanozyme chemiluminescence paper test for rapid and sensitive detection of sars-cov-2 antigen. Biosensors and Bioelectronics 173, 112,817 (2021) 170. Weaver AA Reiser H Barstis T Benvenuti M Ghosh D Hunckler M Joy B Koenig L Raddell K Lieberman M Paper analytical devices for fast field screening of beta lactam antibiotics and antituberculosis pharmaceuticals Anal. Chem. 2013 85 13 6453 6460 23725012 171. Koesdjojo MT Wu Y Boonloed A Dunfield EM Remcho VT Low-cost, high-speed identification of counterfeit antimalarial drugs on paper Talanta 2014 130 122 127 25159388 172. Kaarj K Akarapipad P Yoon JY Simpler, faster, and sensitive zika virus assay using smartphone detection of loop-mediated isothermal amplification on paper microfluidic chips Sci. Rep. 2018 8 1 1 11 29311619 173. Ye X Xu J Lu L Li X Fang X Kong J Equipment-free nucleic acid extraction and amplification on a simple paper disc for point-of-care diagnosis of rotavirus a Anal. Chim. Acta 2018 1018 78 85 29605138 174. Mensah ST Gonzalez Y Calvo-Marzal P Chumbimuni-Torres KY Nanomolar detection limits of cd2+, ag+, and k+ using paper-strip ion-selective electrodes Anal. Chem. 2014 86 15 7269 7273 25023061 175. Yu P Heist CA Remcho VT A novel laminated polycaprolactone/paper/silver electrode for lead (ii) detection Anal. Methods 2017 9 11 1702 1706 176. Wang X Sun J Tong J Guan X Bian C Xia S based sensor chip for heavy metal ion detection by swsv Micromachines 2018 9 4 150 30424084 177. Shimizu FM Pasqualeti AM Nicoliche CY Gobbi AL Santhiago M Lima RS Alcohol-triggered capillarity through porous pyrolyzed paper-based electrodes enables ultrasensitive electrochemical detection of phosphate ACS sensors 2021 6 8 3125 3132 34399053 178. Cioffi A Mancini M Gioia V Cinti S Office paper-based electrochemical strips for organophosphorus pesticide monitoring in agricultural soil Environmental Science & Technology 2021 55 13 8859 8865 34165948 179. Scala-Benuzzi ML Raba J Soler-Illia GJ Schneider RJ Messina GA Novel electrochemical paper-based immunocapture assay for the quantitative determination of ethinylestradiol in water samples Anal. Chem. 2018 90 6 4104 4111 29473416 180. E. Costa-Rama, H. Nouws, C. Delerue-Matos, M.d.C. Blanco-López, M.T. Fernández-Abedul, Preconcentration and sensitive determination of the anti-inflammatory drug diclofenac on a paper-based electroanalytical platform. Analytica Chimica Acta 1074, 89–97 (2019) 181. Guo H Yeh MH Zi Y Wen Z Chen J Liu G Hu C Wang ZL Ultralight cut-paper-based self-charging power unit for self-powered portable electronic and medical systems ACS Nano 2017 11 5 4475 4482 28401759 182. Y. Liu, K. Cui, Q. Kong, L. Zhang, S. Ge, J. Yu, A self-powered origami paper analytical device with a pop-up structure for dual-mode electrochemical sensing of atp assisted by glucose oxidase-triggered reaction. Biosensors and Bioelectronics 148, 111,839 (2020) 183. Lee H Choi S An origami paper-based bacteria-powered battery Nano Energy 2015 15 549 557 184. Shen LL Zhang GR Biesalski M Etzold BJ based microfluidic aluminum-air batteries: toward next-generation miniaturized power supply Lab Chip 2019 19 20 3438 3447 31556903 185. Y. Wang, H.Y. Kwok, W. Pan, H. Zhang, X. Lu, D.Y. Leung, Parametric study and optimization of a low-cost paper-based al-air battery with corrosion inhibition ability. Applied energy 251, 113,342 (2019) 186. Y. Yang, H. Zhang, X. Zhu, D. Ye, R. Chen, Q. Liao, A hollow structure for flow and bendable paper-based zinc-air battery. International Journal of Energy Research (2022) 187. Zebda A Renaud L Cretin M Pichot F Innocent C Ferrigno R Tingry S A microfluidic glucose biofuel cell to generate micropower from enzymes at ambient temperature Electrochem. Commun. 2009 11 3 592 595 188. Noh HB Shim YB Catalytic activity of polymerized self-assembled artificial enzyme nanoparticles: applications to microfluidic channel-glucose biofuel cells and sensors Journal of Materials Chemistry A 2016 4 7 2720 2728 189. Arun RK Halder S Chanda N Chakraborty S A paper based self-pumping and self-breathing fuel cell using pencil stroked graphite electrodes Lab Chip 2014 14 10 1661 1664 24671425 190. Cardoso TM Garcia PT Coltro WK Colorimetric determination of nitrite in clinical, food and environmental samples using microfluidic devices stamped in paper platforms Anal. Methods 2015 7 17 7311 7317 191. E. Trofimchuk, Y. Hu, A. Nilghaz, M.Z. Hua, S. Sun, X. Lu, Development of paper-based microfluidic device for the determination of nitrite in meat. Food chemistry 316, 126,396 (2020) 192. Hu X Lu L Fang C Duan B Zhu Z Determination of apparent amylose content in rice by using paper-based microfluidic chips J. Agric. Food Chem. 2015 63 44 9863 9868 26495809 193. Nogueira SA Lemes AD Chagas AC Vieira ML Talhavini M Morais PA Coltro WK Redox titration on foldable paper-based analytical devices for the visual determination of alcohol content in whiskey samples Talanta 2019 194 363 369 30609544 194. S. Patari, P.S. Mahapatra, in 2021 IEEE Sensors (IEEE, 2021), pp. 1–4 195. Guinati BG Sousa LR Oliveira KA Coltro WK Simultaneous analysis of multiple adulterants in milk using microfluidic paper-based analytical devices Anal. Methods 2021 13 44 5383 5390 34734929 196. Dong M Wu J Ma Z Peretz-Soroka H Zhang M Komenda P Tangri N Liu Y Rigatto C Lin F Rapid and low-cost crp measurement by integrating a paper-based microfluidic immunoassay with smartphone (crp-chip) Sensors 2017 17 4 684 28346363 197. Bhakta SA Borba R Taba M Jr Garcia CD Carrilho E Determination of nitrite in saliva using microfluidic paper-based analytical devices Anal. Chim. Acta 2014 809 117 122 24418141 198. Menger R Bontha M Beveridge J Borch T Henry C Fluorescent dye paper-based method for assessment of pesticide coverage on leaves and trees: a citrus grove case study J. Agric. Food Chem. 2020 68 47 14009 14014 33170700 199. Jiang D Ge P Wang L Jiang H Yang M Yuan L Ge Q Fang W Ju X A novel electrochemical mast cell-based paper biosensor for the rapid detection of milk allergen casein Biosens. Bioelectron. 2019 130 299 306 30776617 200. Srisa-Art M Boehle KE Geiss BJ Henry CS Highly sensitive detection of salmonella typhimurium using a colorimetric paper-based analytical device coupled with immunomagnetic separation Anal. Chem. 2018 90 1 1035 1043 29211962 201. C. Srisomwat, P. Teengam, N. Chuaypen, P. Tangkijvanich, T. Vilaivan, O. Chailapakul, Pop-up paper electrochemical device for label-free hepatitis b virus dna detection. Sensors and Actuators B: Chemical 316, 128,077 (2020) 202. Jilani TN Jamil RT Siddiqui AH H1n1 influenza (swine flu) 2020 Treasure Island (FL) StatPearls 203. Nguyen MP Kelly SP Wydallis JB Henry CS Read-by-eye quantification of aluminum (iii) in distance-based microfluidic paper-based analytical devices Anal. Chim. Acta 2020 1100 156 162 31987136 204. Reboud J Xu G Garrett A Adriko M Yang Z Tukahebwa EM Rowell C Cooper JM based microfluidics for dna diagnostics of malaria in low resource underserved rural communities Proc. Natl. Acad. Sci. 2019 116 11 4834 4842 30782834 205. S. Ardalan, M. Hosseinifard, M. Vosough, H. Golmohammadi, Towards smart personalized perspiration analysis: An iot-integrated cellulose-based microfluidic wearable patch for smartphone fluorimetric multi-sensing of sweat biomarkers. Biosensors and Bioelectronics 168, 112,450 (2020) 206. Kaushik A Tiwari S Jayant RD Marty A Nair M Towards detection and diagnosis of ebola virus disease at point-of-care Biosens. Bioelectron. 2016 75 254 272 26319169 207. Cao L Fang C Zeng R Zhao X Jiang Y Chen Z based microfluidic devices for electrochemical immunofiltration analysis of human chorionic gonadotropin Biosens. Bioelectron. 2017 92 87 94 28189070 208. Honikel MM Lin CE Cardinell BA LaBelle JT Penman AD Direct measurement of a biomarker’s native optimal frequency with physical adsorption based immobilization ACS sensors 2018 3 4 823 831 29533605 209. D. Thompson, Y. Lei, Mini review: Recent progress in rt-lamp enabled covid-19 detection. Sensors and Actuators Reports 2(1), 100,017 (2020) 210. J.P. Broughton, X. Deng, G. Yu, C.L. Fasching, J. Singh, J. Streithorst, A. Granados, A. Sotomayor-Gonzalez, K. Zorn, A. Gopez, et al., Rapid detection of 2019 novel coronavirus sars-cov-2 using a crispr-based detectr lateral flow assay. MedRxiv (2020) 211. Q. Hui, Y. Pan, Z. Yang, based devices for rapid diagnostics and testing sewage for early warning of covid-19 outbreak. Case Studies in Chemical and Environmental Engineering 2, 100,064 (2020) 212. R. Suvanasuthi, S. Chimnaronk, C. Promptmas, 3d printed hydrophobic barriers in a paper-based biosensor for point-of-care detection of dengue virus serotypes. Talanta 237, 122,962 (2022) 213. P. Mufidah Sari, A. Daud, H. Sulistyarti, A. Sabarudin, D. Nacapricha, An application study of membraneless-gas separation microfluidic paper-based analytical device for monitoring total ammonia in fish pond water using natural reagent. Analytical Sciences 38(5), 759–767 (2022) 214. Amor-Gutiérrez O Costa-Rama E Fernández-Abedul MT Fully integrated sampler and dilutor in an electrochemical paper-based device for glucose sensing Microchim. Acta 2021 188 9 1 8 215. A. Pal, H.E. Cuellar, R. Kuang, H.F. Caurin, D. Goswami, R.V. Martinez, Self-powered, paper-based electrochemical devices for sensitive point-of-care testing. Advanced materials technologies 2(10), 1700,130 (2017) 216. Komatsu T Gabatino RR Hofileña H Maeki M Ishida A Tani H Tokeshi M Using a paper-based analytical device designed for remote learning environments to achieve simple quantitative colorimetry without micropipettes J. Chem. Educ. 2021 98 9 3050 3054 217. P. Yomthiangthae, O. Chailapakul, W. Siangproh, Rapid urinary albumin detection using a simple redox cycling process coupled with a paper-based device. Journal of Electroanalytical Chemistry 911, 116,230 (2022) 218. Patari S Datta P Mahapatra PS 3d paper-based milk adulteration detection device Sci. Rep. 2022 12 1 1 14 34992227 219. Zhao J Zhang Y Liu F Yan M Wang X Wang W Sunlight-responsive titania-hydrated tungsten oxide heteronanoparticles/paper-based color-switching film for solar ultraviolet radiation monitors ACS Applied Nano Materials 2022 5 3 4009 4017 220. E. Ghohestani, J. Tashkhourian, B. Hemmateenejad, Colorimetric determination of peroxide value in vegetable oils using a paper based analytical device. Food Chemistry p. 134345 (2022) 221. Maier D Laubender E Basavanna A Schumann S Guder F Urban GA Dincer C Toward continuous monitoring of breath biochemistry: a paper-based wearable sensor for real-time hydrogen peroxide measurement in simulated breath ACS sensors 2019 4 11 2945 2951 31610653 222. M. Asif, F.R. Awan, Q.M. Khan, B. Ngamsom, N. Pamme, based analytical devices for colorimetric detection of s. aureus and e. coli and their antibiotic resistant strains in milk. Analyst 145(22), 7320–7329 (2020) 223. B. O’Farrell, in Lateral flow immunoassay (Springer, 2009), pp. 1–33
PMC009xxxxxx/PMC9744689.txt	==== Front J Econ Behav Organ J Econ Behav Organ Journal of Economic Behavior & Organization 0167-2681 0167-2681 Elsevier B.V. S0167-2681(22)00450-4 10.1016/j.jebo.2022.12.007 Article Anti-social behaviour and economic decision-making: Panel experimental evidence in the wake of COVID-19 Lohmann Paul M. ab Gsottbauer Elisabeth cd You Jing e⁎ Kontoleon Andreas bf a El-Erian Institute of Behavioural Economics and Policy, Judge Business School, University of Cambridge, United Kingdom b Centre for Environment, Energy and Natural Resource Governance, Department of Land Economy, University of Cambridge, United Kingdom c Institute of Public Finance, University of Innsbruck, Austria d London School of Economics and Political Science (LSE), Grantham Research Institute on Climate Change and the Environment, United Kingdom e School of Agricultural Economics and Rural Development, Renmin University of China, China f Department of Land Economy, University of Cambridge, United Kingdom ⁎ Corresponding author. 13 12 2022 2 2023 13 12 2022 206 136171 31 1 2022 18 11 2022 10 12 2022 © 2023 Elsevier B.V. All rights reserved. 2022 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. We systematically examine the acute impact of exposure to a public health crisis on anti-social behaviour and economic decision-making using unique experimental panel data from China, collected just before the outbreak of COVID-19 and immediately after the first wave was overcome. Exploiting plausibly exogenous geographical variation in virus exposure coupled with a dataset of longitudinal experiments, we show that participants who were more intensely exposed to the virus outbreak became more anti-social than those with lower exposure, while other aspects of economic and social preferences remain largely stable. The finding is robust to multiple hypothesis testing and a similar, yet less pronounced pattern emerges when using alternative measures of virus exposure, reflecting societal concern and sentiment, constructed using social media data. The anti-social response is particularly pronounced for individuals who experienced an increase in depression or negative affect, which highlights the important role of psychological health as a potential mechanism through which the virus outbreak affected behaviour. Keywords Anti-social behaviour Coronavirus Risk preferences Time preferences Natural experiment Panel data Social media data ==== Body pmc1 Introduction The novel coronavirus SARS-CoV-2, causing the infectious disease now known as COVID-19, was first reported in China in the city of Wuhan in December 2019.1 In less than three months, the new virus spiralled into a national health crisis and global pandemic. Governments have faced unprecedented challenges to mitigate the spread of the virus and in response have imposed extensive policies that limit social contact and have mandated forms of preventative behaviour. What are the immediate impacts on social behaviour and economic decision-making of such an unprecedented public health crisis? For example, how does direct exposure to COVID-19 affect people’s proclivity for acting pro-socially, their attitudes towards taking risks or their patience levels. This question is of particular importance as economic preferences have been shown to be an important predictor of people’s willingness to adopt emergency measures at the early critical stages of such a health crisis, including social distancing, hand hygiene and wearing of face masks meant to contain the further spread of the virus (e.g. Nikolov, Pape, Tonguc, Williams, Müller, Rau, 2021, Campos-Mercade, Meier, Schneider, Wengström, 2021). To manage the pandemic effectively, it is vital to understand factors that drive people’s willingness to comply with confinement measures, especially those that could be significantly affected by the exposure to COVID-19 itself. To shed light on this question, we use a unique dataset of longitudinal experiments to examine the effect of exposure to COVID-19 on anti-social behaviour and economic decision-making. The experiments were conducted in October and December 2019 right before the outbreak and shortly after the first wave of the pandemic in March 2020, relying on a large sample of university students from Beijing. Students were all based in Beijing during the baseline survey and were spread across 183 cities in China during endline survey in March 2020. Unlike other studies on the impacts of COVID-19, our panel data enables identification not only to a higher degree of internal validity, as we were able to track the change in behaviour and preferences of the same individuals before and after the outbreak, but also to larger external validity with wider geographic, epidemic and socioeconomic representation. More broadly, our paper speaks to a sizeable body of empirical literature assessing if negative shocks (e.g., violent conflicts, natural disasters, economics crisis) can bring about systematic changes in economic decision-making and affect the temporal stability of economic preferences (for an overview of largely mixed findings see, Chuang and Schechter, 2015).2 A related literature focuses on the stability of preferences in relation to acute stress events and scarcity, again producing mixed results.3 We also add to a number of papers exploring the impact of COVID-19 on economic and social preferences, including research focusing on risk and time preferences (Angrisani, Cipriani, Guarino, Kendall, Ortiz de Zarate, 2020, Li, Huang, Tam, Hong, Bu, Hanspal, Liao, Liu, 2020, Drichoutis, Nayga, 2021, Guenther, Galizzi, Sanders, 2021, Harrison, Hofmeyr, Kincaid, Monroe, Ross, Schneider, Swarthout, 2022), social preferences (Branas-Garza, Jorrat, Alfonso, Espin, García, Kovarik, 2022, Buso, De Caprariis, Di Cagno, Ferrari, Larocca, Marazzi, Panaccione, Spadoni, 2020, Grimalda, Buchan, Ozturk, Pinate, Urso, Brewer, 2021) and papers assessing various preference measures (e.g. Alsharawy, Ball, Smith, Spoon, 2021, Bokern, Linde, Riedl, Werner, Shachat, Walker, Wei, 2021). Findings from all of the aforementioned studies on the effect of the outbreak of the pandemic on economic and social preferences are mixed. One reason for these mixed findings might be that these papers cover a broad spectrum of research approaches, amongst others, differing in the use of incentivized and non-incentivized preference measures, sampling among a student or a more general population sample and data collection taking place before and after the outbreak or only after the outbreak of COVID-19. In addition, all of the aforementioned studies were conducted in many different countries and cultural contexts. The closest of these papers to ours are Shachat et al. (2021); Li et al. (2022) and Bu et al. (2020) making use of risk and social experimental preference measures elicited among Chinese samples to assess the impact of the first wave of COVID-19 on the stability of these preferences. While we acknowledge that our experimental approach holds many similarities to these papers, there are also some notable differences with respect to research design and identification strategy including the use of a within- instead of between-subject design, additional survey data to study potential mechanisms and a more nuanced analysis with respect to exposure to the virus outbreak through ample geographical variation in virus prevalence. Note that the main sample difference to Shachat et al. (2021) and Bu et al. (2020) is that both studies heavily draw on students located in Hubei province where the majority of COVID-19 cases were reported, while our study relies on geographical variation in students’ location across all of mainland China (only 10 participants, i.e. 1.92% of the sample were located within Hubei province).4 We summarize similarities and differences to these studies in Table A1 in the Appendix. Our paper also links to research on the connection between economic and social preferences and health behaviours, including the willingness to take protective action and the demand for vaccines (Böhm, Betsch, Korn, 2016, Chapman, Coups, 1999, Galizzi, Miraldo, 2017, Sutter, Kocher, Daniela, Trautmann, 2013). For example, recent research with respect to the spread of COVID-19 finds that pro-social preferences and patience positively correlate with personal protective behaviour related to COVID-19, while risk tolerance negatively impacts the willingness to engage in such behaviour (Campos-Mercade, Meier, Schneider, Wengström, 2021, Müller, Rau, 2021).5 However, the direction of these effects would become unclear if exposure to an acute public health crisis itself could trigger behaviour and preferences to change in different directions for significant segments of the population. On the one hand, evidence from economics and psychology suggests that people exposed to a major crisis event may more likely display selfish and reckless behaviour (Fisman, Jakiela, Kariv, 2015, Fritsche, Jugert, 2017). Anecdotal evidence from panic buying and increased racial discrimination, xenophobia, and riots in response to the coronavirus outbreak is indicative of such behaviour. On the other hand, research also indicates that disaster and crisis lead individuals to engage in widespread altruism and acts of solidarity (Bauer, Blattman, Henrich, Miguel, Mitts, 2016, Solnit, 2010). With respect to the COVID-19 outbreak, the public’s willingness to engage in cooperative behaviour including social distancing as well as the formation of neighbourhood networks to assist vulnerable groups speaks to this strand of literature. The research described in this paper contributes to the aforementioned literatures in several important ways. First, it adds to the body of empirical work testing the theoretical assumption of stable preferences over time. Our study explores the acute effect of a public health crisis on temporal stability of fundamental preferences predictive of economic and social behaviour, including risk aversion, patience, trust, cooperation, altruism, norm enforcement and anti-social behaviour. More importantly, it also explores potential mechanisms behind any changes in preferences and behaviour. Second, unlike a number of cross-sectional studies, it applies a ‘dose-response’ difference-in-difference framework to panel data, tracking the same individuals before and after the virus outbreak. Our identification strategy exploits within-individual variation in economic decision-making and exogenous variation in exposure to the virus across 183 cities to assess causal impacts of the crisis. Importantly, our design resembles a type of natural experiment, whereby the individuals’ locations (and thus exposure to the virus) are pre-determined by factors unrelated to the virus outbreak. Compared with between-individual identification, it yields more precise estimates by explicitly controlling for individually heterogeneous confounders (fixed effects) to preferential changes. Third, it combines data from multiple sources and disciplines. To ascertain incentive compatible economic decision-making, we employ well-established experimental protocols as opposed to responses to purely hypothetical behavioural questions. Together with a range of survey variables from economics and psychology, we can capture both behavioural and trait-like characteristics. In order to comprehensively reflect what COVID-19 means for individuals, we go beyond simple epidemiological measures of virus prevalence and exploit information from big-data extracted from Chinese social media to construct two additional measures of virus exposure capturing social concern and sentiment: (1) an innovative index reflecting public concern/anxiety based on internet search volume sourced from China’s largest search engine (Baidu Inc.) and (2) a novel index of expressed negative sentiment based on linguistic text analysis of 523,222 tweets posted on the main microblogging platform (Sina Weibo). Finally, to better purge non-random components of the exposure to the virus in identification as well as to minimise omitted variable problems in regressions, we collected data from various sources including population mobility based on mobile phone check-ins at Baidu Inc. and official air quality information from 1436 air monitoring stations across China. We also hand-collected and coded city-level lockdown policies on various aspects of life, work, and education from government sources. We show a substantial and statistically significant increase in anti-social behaviour for those individuals more intensely exposed to the virus outbreak. In contrast, our measures of pro-social behaviour and economic preferences are largely unaffected by the COVID-19 shock. Moreover, our analysis of potential mechanisms suggests that increases in depression and negative affect are likely driving the observed relationship for anti-social behaviour. The indication that mental well-being is likely responsible for the increase in anti-social behaviour can inform better targeted policies and relief programs, including increased attention to mental health issues at the onset of a public health emergency and in turn greater investment into mental health services (Liu, Yang, Zhang, Xiang, Liu, Hu, Zhang, 2020, Dong, Bouey, 2020). Our paper is structured as follows. Section 2 describes the design of study, detailing our outcome, control and mediation variables. Section 3 presents our identification strategy and how we address potential endogeneity concerns. Section 4 describes our empirical strategy, presents sample statistics and outlines how we address attrition. Section 5 presents our results, the sensitivity analysis undertaken, as well as the potential mechanisms explored. Section 6 concludes with a discussion of our main findings and how these relate to the relevant literature. 2 Study design The experiment was conducted on a sample drawn from the general student population of universities in Beijing (with the majority of students enrolled at Renmin University) in October 2019.6 We informed participants about the longitudinal nature of the study and asked them to consent to participate in multiple experimental survey waves.7 Students were offered a 10 Yuan (1.50 USD) flat-fee payment for participation in the panel study and the opportunity to obtain bonus payments based on their decisions in the experiments. Note that we follow standards in experimental economics to conduct an incentive-based experiment in which participants obtain a monetary reward based on the results of their decisions.8 Experimental protocols and surveys were administered online using a survey tool integrated into WeChat, a popular mobile messaging application in China. The average payment per participant was approximately 32 Yuan (5 USD), including a 10 Yuan show-up fee for each wave). Average completion time per wave varied between 15 and 20 min. Data was collected in three waves. Wave 1 (N=793) was conducted in October 2019 and designed as a baseline survey including questions on participants’ socio-demographics which were not repeated in later waves. Wave 2 (N=650) was conducted in December 2019 and Wave 3 (N=539) in March 2020 which comprised elements of both proceeding surveys as well as questions specific to the COVID-19 crisis. Importantly, Waves 1 and 2 were conducted before the outbreak of COVID-19 in China, while Wave 3 at a point when the epidemic in China had significantly slowed and new cases were close to zero. Fig. 1 displays a detailed timeline of events and highlights the spread of the epidemic, indicating daily new confirmed cases of COVID-19 in China.Fig. 1 Timeline of data collection and virus outbreak. Note: Confirmed cases of COVID-19 were obtained from official sources (State Council, provincial governments, and the Chinese CDC). Fig. 1 The experimental modules which were employed across the three waves of the survey consist of well-established experimental games. To measure anti-social behaviour as well as economic preferences on risk and time/discounting (our main outcome variables) we use the following incentivized decision tasks: a joy of destruction game; a take game with and without deterrence; a third-party punishment game; a lottery choice task; an investment game and a convex time budget task. In addition, we use a hypothetical trust game and one-shot public good game to capture other aspects of social preferences (results presented in the Appendix). The survey waves also included standardized survey modules to obtained relevant socio-economic control variables, but also measures of participant’s cognitive functioning and well-being. The latter two sets of measures would serve as potential mechanisms explaining the effects of Covid exposure on our outcome variables. In particular, to measure cognitive functioning, we use a set of Raven’s matrices and a five-item self-completion questionnaire to assess participants’ momentary level of ego-depletion. For psychological and physiological well-being, we measure self-reported subjective well-being, depressive symptoms, positive and negative affect, sleep quality and general health status of all participants. Table 1 provides an overview of each survey module. Table A2 in the Appendix provides more detail on the experimental modules and how the outcome and mediating variables were defined. Note that Wave 3 consisted of all experimental modules, while Waves 1 and 2 were made up of sub-sets of these.Table 1 Panel survey modules. Table 1Wave N Anti-social behaviour Risk & time preferences Cognition Well-being Pro-social behaviour 1 793 Lottery Choice Task$, Investment Game CES-D, General health Trust Game, Public Good Game 2 650 Joy of Destruction$, Take Game$, Punishment Game$ Convex Time Budget$, Lottery Choice Task$ Raven$, Depletion CES-D, General health, Subjective well-being, PANAS 3 539 Joy of Destruction$, Take Game$, Punishment Game$ Convex Time Budget$, Lottery choice task$, Investment Game Raven$, Depletion CES-D, General health, Subjective well-being, PANAS Trust Game, Public Good Game Note: Waves 1 & 2 were collected before the COVID-19 outbreak while Wave 3 was collected after. Tasks marked with $ were incentivised. CES-D = Centre for Epidemiologic Studies Depression Scale; PANAS = Positive and Negative Affect Schedule. To incentivise truthfulness and effort, the majority of tasks were incentivised so that payoff depended on the participant’s choices. The incentivized tasks were presented in separate questionnaire parts to participants.9 In Part I of the questionnaire, participants were presented with the Joy of Destruction Game, the Take Game and the Third-Party Punishment game and subjects were paid on the basis of one randomly selected task from Part I.10 The average endowment for each task was approximately 20 Yuan (3 USD). In Part II, participants made a total of 25 decisions across a Lottery Choice Task and a Convex Time Budget Task with significantly increased stakes (payoff between 56 and 140 Yuan, equivalent to 8.60–21.50 USD). Participants were informed that 30 students would be selected at random to receive payment for one of their decisions (selected at random) from Part II. In Part III, participants were incentivized to complete the Raven Matrices test, in which we paid participants for each correct answer (out of 9). Note that the trust game and the one-shot public good game were not incentivized in any of the waves.11 At the end of each wave, the decision tasks that were used for payment were randomly selected and respondents received their respective payments to their WeChat Wallet on the following day. Note that the time preferences payments were delivered according to the time schedule indicated in the selected decision task (details provided below). All instructions were provided in Chinese and all choices were framed in terms of Chinese Yuan (CNY). The English translation of the instructions is included in Appendix C. In the following subsection we describe the survey modules and key variables used in our analysis in more detail. 2.1 Outcome variables 2.1.1 Anti-social behaviour The anti-social behaviour module consists of two separate incentivized games to elicit different dimensions of people’ willingness to engage in anti-social behaviour. The binary Joy of Destruction (JOD) game provides a measure of nasty behaviour (Abbink and Herrmann, 2011). In this two-player game, participants were anonymously matched in pairs (each with an initial endowment of 20 Yuan) and then faced the binary decision whether to destroy their assigned partner’s endowment by half at a cost of 2 Yuan or maintain the status quo. Participants were further informed that, with a one third probability, the other player’s endowment will be reduced to 10 Yuan, regardless of their decision. The design of JOD game removes all conventional motivations for anti-social behaviour and further allows destructive behaviour to be partially hidden behind a component of random destruction. The primary outcome variable from this task is a binary indicator identifying individuals that chose to destroy their counterpart’s endowment. The Take Game provides a measure of covert anti-social behaviour in the form of stealing or theft (Schildberg-Hörisch and Strassmair, 2012). In this two-player game, participants were anonymously matched and provided unequal endowment (of 10 Yuan or 18 Yuan). The participants then had to decide whether to take from the other player’s initial endowment in two different scenarios. In the first scenario, the player could take any amount (between 0 and 18 Yuan) without facing any consequences. In the second scenario, the player could take any amount but faced a 60% probability of being detected, effectively reducing their payoff to 6 Yuan due to a penalty. Note that the game was constructed as such that no losses or negative payments were possible. From this task we obtain two primary outcome variables for our analysis: (1) a continuous measure of taking without and (2) with a risk of being detected.12 2.1.2 Risk and time preferences Risk preferences are obtained using a standard incentivised Lottery Choice Task Eckel and Grossman (2002). In this task, participants had to decide between six lotteries each with a 50% chance of paying a lower or higher amount. Lotteries were increasing in variance, total pay-off and riskiness. Find instructions in the Appendix C4, Part 4.2. Based on the chosen lottery, we obtained the participant’s constant relative risk aversion (CRRA) parameter interval. For our analysis, we calculate the CRRA interval midpoint for each participant in a given survey wave, with a higher value indicating greater risk aversion.13 In an additional task, we obtain a simple measure of risk aversion with the help of a non-incentivized Investment Game based on Gneezy and Potters (1997). Participants could invest part of their hypothetical 20,000 Yuan endowment into a lottery with a winning probability of 50%. The higher the investment, the higher the risk participants are willing to take. Time preferences are elicited using Convex Time Budgets (CTB) following Andreoni et al. (2015). Participants made 24 consecutive decisions between sooner or later payments, across four different timeframes, with six budget lines for each timeframe. Participants thus faced decisions over payment ‘today and 5 weeks from today’, ‘today and 9 weeks from today’, ‘5 weeks from today and 10 weeks from today’ and ‘5 weeks from today and 14 weeks from today’. The 24 budget lines and instructions are displayed in Appendix C4, Part 4.3. Prior to our main analysis, we estimated the individual-level parameters beta and delta parameters via non-linear least squares following Andreoni et al. (2015). For our main analysis, we utilize the individual-level delta parameter as a measure of patience and construct a binary measure of present bias equal to one if a participant’s individual-level beta parameter is smaller than 1. 2.2 Control and mediation variables We collect extensive socio-demographic control variables relevant to the Chinese context including, participants urban or rural origin (or ‘Hukou’ status) and whether participants have siblings (‘only child’ due to family planning). In addition, we use a set of survey questions to assess cognitive functioning and well-being, which may serve as potential mechanisms for changes in economic decision-making. To measure cognitive functioning, we used a subset of Raven’s Standard Progressive Matrices (Bilker et al., 2012) and pay subjects for each correct answer. Cognitive performance was indexed by the sum of correctly solved matrices (range 0–9). In addition, we assessed participants’ momentary and self-reported state of ego-depletion, which reflects an individual’s self-control capacity at a given moment, according to ego-depletion theory (Baumeister et al., 1998).14 This measure was obtained from a modified 5-item Depletion Scale adapted from Twenge et al. (2004) where a higher score indicates higher levels of depletion.15 The well-being module consists of a selection of survey questions to capture different dimensions of well-being. We use the Center for Epidemiologic Studies Depression Scale (CESD) 10-item scale as a validated self-reported instrument to measure the prevalence of depressive symptoms (Andresen et al., 1994). Respondents are asked to report the frequency at which they experienced a given mood or symptom during the past week on a four-point scale, ranging from zero (“none of the time”) to three (‘most of the time’). A depression score is obtained by totalling responses to each of the 10 items (range 0–30). Moreover, we construct a binary measure indicating the presence of depressive symptoms for subjects with a depression score of 10 or higher (Andresen et al., 1994). To measure short-term mood on the day of the survey, we use the international short form of the Positive and Negative Affect Schedule (PANAS-ISF) consisting of a 10-item self-reported questionnaire (Thompson, 2007). Using the respective negative and positive affect items (five each), we construct scores for positive and negative affect, where higher scores indicate greater presence of positive or negative mood on the day of the survey (range 5–25). To measure subjective well-being, we focus on three dimensions including life satisfaction, happiness, and meaningfulness of life, where higher scores indicate higher levels of subjective well-being in the respective categories. We also check the general health status of our participants, using responses to a question on their general health condition ranging from 1 to 5, indicating very poor to very good health status on the day of the survey. See Appendix C4 and C5, for instructions. Finally, we also assess participant’s pro-social behaviour with some simple hypothetical tasks: A standard one-shot Public Good Game was used to obtain a measure of cooperation (see Appendix 2, Part C2, for instructions. In this game, participants could invest part of their hypothetical endowment (10,000 Yuan) into the production of a public good with a return of 1.6. We also used a Trust Game to obtain a measure of trust in an investment setting (Berg et al., 1995). Participants chose how much of their hypothetical endowment (100 Yuan) to invest into a partner who doubles the investment and decides how much to return. Finally, we used an incentivized Third-Party Punishment Game (Fehr and Fischbacher, 2004) to measure both prosocial behaviour and third-party sanctioning behaviour for violations of a distribution norm (Fehr and Fischbacher, 2004). As in a classic dictator game, players first decided whether to transfer between 0 and 10 Yuan of their 20 Yuan endowment to an anonymously matched recipient. They then took the role of a third party observing another player’s transfer decision, with the option to enact costly punishment for each possible transfer amount sent by the observed dictator. In our setting, the third-party observer had an endowment of 10 Yuan and could use any of this amount to punish the dictator by reducing their endowment by a factor of three (e.g., 2 Yuan would reduce the dictator’s endowment by 6 Yuan). As players faced multiple decisions, they were informed that one of their choices would be randomly selected for payment. From this game we construct three primary outcomes for our analysis: (1) an incentivised measure of (observed) giving from the dictator game, as a measure of pro-social behaviour or altruism, (2) the amount spent to punish if the observed dictator transfers zero and (3) a binary indicator identifying subjects that were willing to pay any amount to punish a dictator that gave zero.16 2.3 Summary statistics Table 2 presents summary statistics for all outcome variables employed in the analysis, as well as the socio-demographic characteristics of the full sample pooling responses from all waves (if N=1566 the variable was collected in all three waves, if N=1044 the variable was collected in only two of three waves).17 Most notably, with respect to our main outcome variables related to anti-social behaviour we observe that 16% of participants decided to destroy their counterpart’s endowment, and 9.48 (10.23) Yuan were taken, on average, in the Take Game with (and without) deterrence. Both risk measures suggest that the sample was slightly risk averse, and 67% of participants were classified as present biased.Table 2 Summary statistics. Table 2 Mean SD Min Max N Anti-social Behaviour Joy of Destruction (Destroy = 1) 0.16 0.37 0.00 1.00 1044 Taking (¥) 10.23 6.30 0.00 18.00 1044 Taking with Deterrence (¥) 9.48 6.73 0.00 18.00 1044 Risk & Time Preferences Risk Aversion (CRRA midpoint - EG) 2.99 2.78 −0.50 6.73 1566 Risk Taking (GP) 7156.81 4086.02 0.00 20000.00 1044 Present Bias (Yes = 1) 0.67 0.47 0.00 1.00 1026 Patience (δ parameter) 0.98 0.12 0.00 1.00 1026 Pro-social Behaviour & Norm-enforcement Cooperation (¥invested in PGG) 4138.33 3370.25 0.00 10000.00 1044 Trust (¥invested) 43.55 25.29 0.00 100.00 1044 Dictator Giving (¥) 3.91 3.44 0.00 10.00 1044 Punishment (¥) 0.59 0.49 0.00 1.00 1044 Punish (Punish = 1) 2.08 2.29 0.00 10.00 1044 Cognition and Health Cognitive Ability (correct puzzles) 6.70 1.39 1.00 9.00 1044 Depletion (score) 1.68 3.54 −7.00 11.00 1044 Depression (score) 10.60 5.67 0.00 29.00 1566 Depressive Symptomns (Yes = 1) 0.53 0.50 0.00 1.00 1566 Negative Affect (score) 9.81 4.21 5.00 25.00 1044 Positive Affect (score) 12.90 3.41 5.00 21.00 1044 General Health (scale) 3.81 0.80 1.00 5.00 1566 Socio-demographic Characteristics Age 19.85 1.53 17.00 29.00 522 Female (%) 0.82 0.39 0.00 1.00 522 Rural Hukou (%) 0.21 0.41 0.00 1.00 522 Only Child (%) 0.64 0.48 0.00 1.00 522 Economics/Finance Major (%) 0.44 0.50 0.00 1.00 522 Year of Study 2.56 1.16 1.00 6.00 522 Note: Table displays the summary statistics for the full sample by pooling data from all three waves (where applicable). The ‘Cognition & Health’ section includes potential mechanism influencing decision-making including (i) cognitive ability and depletion, (ii) emotional affect and depressive symptoms and (iii) general health. We also obtained respondents ‘Socio-demographic Characteristics’ from the baseline demographic survey (N=522) which was conducted in October 2019. 3 Identification We exploit geographical variation in virus prevalence to estimate the causal effect of virus exposure on economic decision-making (similar to Bu et al., 2020). Although initial recruitment (prior to the COIVD-19 crisis) took place at Beijing universities in October 2019, students were geographically (and exogenously) dispersed across the country by the time of the 3rd Wave of data collection (14th–17th March). We also collected students’ travel history from the end of their academic term to our 3rd survey wave date. Section 3.2 below provide an in-depth discussion on possible threats to our identification strategy and how these were addressed. At the time of Wave 3 data collection, 73.4% of participants had travelled outside Beijing and returned to their respective hometowns or family homes to celebrate the Spring Festival (25th January), the most important national holiday in China. For generations, it has been a very strongly and widely adhered tradition to celebrate Chinese New Year with one’s family. Note that the locations where students originate from are geographically diverse due to the college admission rule that has been implemented since 1978. The Ministry of Education and provincial governments jointly set up regional admission quotas according to not only provincial socioeconomic and demographic characteristics but also universities’ classifications, for the purpose of equal access to higher education across regions and ethnic groups. After the national college entrance exam in every June, the colleges/universities will announce their subject- and province-specific admission quotas according to the general guidelines of the Ministry and the provincial governments. Students submit their applications to colleges/universities according to these quotas and their predicted exam performance during June and August. The academic year starts in early September. Thus, the dispersion of our participants’ hometowns has been pre-determined by factors unrelated to those accounting for the distribution of COVID-19 prevalence.18 Shortly after the Spring Festival, nationwide travel restrictions were imposed, and the university spring term was postponed indefinitely. Effectively, the Ministry of Education restrained all students at the cities and towns they were located in late January 2020. This means, participants in our sample were located in 183 cities across China when the endline survey took place, with varying degrees of virus prevalence when we fielded our 3rd survey Wave. Importantly (and what uniquely benefits our identification) is that participants’ geographic dispersion throughout the virus outbreak was totally unrelated to the COVID-19 crisis nor to different levels of COVID-19 exposure. Hence, our data has characteristics of a natural experiment in that treatment assignment (or in our case students’ exposure to different degrees of COVID-19) has been largely determined by exogenous distribution of their geographic locations as a result of the pre-determined universities’ admission across regions coupled with the government imposed domestic travel ban. Fig. 2 provides a graphical illustration of the locations of our participants and corresponding city-level virus prevalence at the time of the third survey.Fig. 2 Survey participants’ locations during survey wave 3 and virus prevalence. Fig. 2 3.1 Measures of virus exposure For robustness, we use three key measures of virus exposure.19 See 3 for a summary. First, we use a standard epidemiological measure of disease prevalence: the logged number of confirmed cases per million inhabitants at the city-level, which we obtained from a variety of official sources including central and provincial governments and the Chinese Centre for Disease Control and Prevention (CDC). We then match cumulative case statistics on the date of the survey in March 2020 with participants’ location. Cumulative case prevalence per million inhabitants in the 183 cities where our participants reside during the March survey fall between 0 and 5658. In our analysis, we use the log-transformed COVID-19 counts.20 Table 3 Exposure variables. Table 3 N Mean SD Min Max City-level Cases 183 47 419 0 5658 City-level Cases (logged) 183 2 1 0 9 Baidu Search Index 183 80,443 78,138 5669 647,294 Baidu Search Index (logged) 183 11 1 9 13 Negative Sentiment Index 179 2 0 1 3 Note: COVID-19 cases are population adjusted at the city-level (per 1 million inhabitants). Baidu Search Index is the city-level sum of search volumes for 20 Keywords related to COVID-19 between 23rd January and 17th March (see Table A3 for individual keywords). Negative Sentiment Index is the city-level average share of negative emotions expressed across all Sina-Microblog posts discussing COVID-19, shared between 7th and 14th March Data Sources: (1) Authors’ compilation of official data from the State Council, provincial governments, and the Chinese CDC. (2) & (3) Authors’ compilation of Baidu search data and Sina Weibo data. Second, we construct a novel measure of city-level concern about the virus outbreak based on internet search data from Baidu, the most popular online search engine in China. The Baidu database provides daily population weighted search volume indices for commonly searched (coronavirus related) keywords at the city level. A high value of the Baidu ‘concern index’ for a certain keyword indicates that many people searched for information on the relevant keyword and cared about the relevant topic. The index has been widely applied in public health research for disease monitoring and prediction (He, Chen, Chen, Wang, Shen, Liu, Suolang, Zhang, Ju, Zhang, Du, Jiang, Pan, Min, 2018, Li, Liu, Zhu, Lin, Zhang, He, Deng, Peng, Xiao, Rutherford, Xie, Zeng, Li, Ma, 2017, Yuan, Nsoesie, Lv, Peng, Chunara, Brownstein, 2013), the measurement of health-related public concern and awareness (e.g. Dong et al., 2019) and more recently also to the COVID-19 outbreak in China (Xiong et al., 2020). We extracted search volume indices for 20 keywords related to general interest searches about COVID-19 (e.g. novel coronavirus) and more specific to symptoms (e.g. dry cough) and personal protective measures (e.g. N95 masks) indexed at the city level (see Appendix Table A3 for a list of all keywords used). To capture overall city-level concern during the virus outbreak, we calculated the sum of all search term indices during the peak of the COVID-19 outbreak, between Wuhan Lockdown (23rd of January) and the date of the survey. We again use the log-transformed Baidu concern index for our analysis. Fig. 3 displays the search volume indices between January and April for three popular keywords, as well as our 20-Keyword index.Fig. 3 Time series Baidu index. Note: The dashed lines indicate the dates on which the CDC announced the highest emergency response level (January 15th), the lockdown of Wuhan (23rd January) and the date of the third Survey was released (14th March). Fig. 3 Third, we construct a novel city-level index of expressed (negative) sentiment related to COVID-19 from social media, as online sharing of emotional content specific to COVID-19 has the potential to bring about long-run societal change via emotional contagion (Steinert, 2020). For this, we extracted microblog posts (or tweets) from Sina Weibo, the Chinese equivalent to Twitter and one of the most popular social media platforms in China.21 First, we extracted 523,222 geotagged microblog posts with the keyword novel coronavirus (‘xin guan’) which were posted online during the week prior to the third survey wave (from 0:00 am on 7th March to 5:00 pm on 14th March). Posts were recorded in 179 of the 183 cities in our sample. Second, we utilized the Linguistic Inquiry Word Count (LIWC) method, an automated text analysis method widely applied in psychology, which measures psychological and linguistic dimensions of written expression (Pennebaker and King, 1999). We employ the simplified Chinese version of the LIWC adapted by Gao et al. (2013). The LIWC text-processing programme uses a set of dictionaries to calculate the percentage of words that express positive and negative emotions for each microblog post. We construct our measure of expressed negative sentiment in a given city by calculating the average share of negative emotions expressed across all posts discussing COVID-19 in the week before the third survey was disseminated. The average score is recoded so that higher values represent greater negative mood (see Table 3 for details). Both the Baidu search index and the negative sentiment index correlate positively to the infection rate, with the correlation coefficients being r=0.6 and r=0.2, respectively. The distributions across cities of the two indices do not deviate from that of the infection rate. We believe that the two indices provide valid measures of social sentiment, reflecting the intensity of exposure to the virus. 3.2 Threats to identification Our identifying assumption relies on virus exposure being randomly assigned across participants. There are two possible sources of endogeneity that could undermine our identification – students’ geographic dispersion and the spread of the virus. We discuss below how both concerns do not apply in our case. 3.2.1 Participants’ location sorting As discussed above, the pre-determined university admissions rule benefits our identification strategy by exogenously dispersing our participants across locations, which rules out potential bias from residential sorting. Moreover, the timing of student mobility in January 2020 was pre-determined exogenously by their term dates relative to the Chinese New Year.22 However, one may be concerned that individuals’ adaptive behaviour prior to the event undermines the estimated impact.23 Specifically, students’ travel decisions with respect to timing and destination may be related to how the unfolding disease situation was unfolding. To explore if this is the case, we first look at the descriptive statistics with respect to student movements. We observe that only 33 students (6% of the sample) whose registered Hukou (hometown) was not Beijing actually stayed in Beijing after the academic term had ended in December 2019 and none of these were from Hubei Province, the region most affected by the virus outbreak. During the holidays a small percentage of students normally remains in Beijing for various reasons (e.g., visiting family, internships, selection of civil servants, additional academic commitments). At the time of the 3rd survey wave, only 5 of these students (<1% of the total sample) had remained on the campuses that we surveyed. Hence, the raw data itself suggests that we do not observe any discernible patterns of adaptive behaviour that could undermine our identification strategy. To further investigate this concern, we explore using regression analysis whether students’ travel decisions are independent of virus prevalence. First, we regress students’ departure dates from Beijing on their initial (baseline) preferences, socio-demographic characteristics, their host university and their destination city. We do not find any significant estimates. Second, we regress a dummy variable equal to one if a student travelled to an alternative destination (i.e. not their hometown) or stayed in Beijing on future virus prevalence in their respective hometowns and a set of province dummies in which their hometown is located. Results show that whether students returned to their hometowns or not is unrelated to future virus prevalence. Moreover, only 28 students ever moved between neighbouring cities after January 23rd when Wuhan was locked down. In all cases, this was reported as visits to relatives, which is also part of the traditional celebration of the Chinese New Year. Overall, these findings clearly indicate that students did not behave adaptively in terms of mobility in response to the possible outbreak. Finally, students’ mobility after the initial lockdown of January 2020 was strictly forbidden, and this was retained when the spring term started in late February. The Ministry of Education required all levels of schools to deliver online courses, and all students to stay home. College students were not allowed to return to their colleges.24 The timing of leaving Beijing and the subsequent restriction on student mobility make their cumulative exposure to the virus situation in their current cities less likely to be individually selected. That said, individual fixed effects in our panel model mitigate any remaining concerns regarding endogenous adaptation. 3.2.2 Dispersion of the virus Whilst the initial outbreak in Wuhan can be deemed an unanticipated event, the further dispersion of the virus across China is unlikely to have followed an entirely random pattern. There are two possible confounding factors. First, according to the Chinese Emergency Law, there are four levels of emergency (from 1 (high) to 4 (low)) and from the second to the fourth level, the provincial governments are responsible for designing and implementing policies to control and prevent the infectious diseases. The State Council announced the highest level on 23rd January and adjusted it to Level 2 on 23rd February. Given our sample dates in March, it is likely that provincial policies and implementation affect individuals’ most recent exposure (in the time domain) to the disease. Second, conditional on provincial environment, socioeconomic development (e.g., health facilities, population density) and geographic location of the city are plausible factors affecting individuals’ exposure to local outbreaks (in the spatial domain). There is evidence which suggests that the virus spread was largely determined by population flows from Wuhan to other cities in China in the days before strict travel restrictions from and to Wuhan were enacted (Kraemer et al., 2020). If confounding factors exist, we need to control for these in our main specification. To determine which city-level factors might confound our results, we regress our three measures of city-level virus exposure on a set of city-level variables, which have been found to affect the dispersion of COVID-19, most importantly the rate of migration between Wuhan and other cities in China. To calculate population mobility we extracted data on inter-city population flows from the Baidu Migration Database (https://qianxi.baidu.com/) tracking individuals’ check-in locations in all Baidu applications (e.g., Baidu map, search, takeaway, and social media ‘tieba’) through their mobile devices. We use the average population inflow from Wuhan as a share of total immigration to each of our sample cities between 20th and 23rd January. Higher values indicate that a larger proportion of the inflowing population originated from Wuhan, which reflects a greater connectedness between Wuhan and the respective city. Following recent research (e.g. Becchetti, Conzo, Conzo, Salustri, 2020, Pluchino, Inturri, Rapisarda, Biondo, Moli, Zappala’, Giuffrida, Russo, Latora), we further control for city-level population density, the number of hospitals and doctors per million inhabitants, the amount of city-level health expenditure as a share of total fiscal expenditure, GDP per capita and annual average Air Quality Index (AQI) based on daily records of 1436 air monitoring stations since 2015.25 The stringency and duration of lockdown may also significantly affect the development of city-level virus outbreaks. We manually collected data of official re-opening dates for shops, restaurants, indoor and outdoor activities, respectively, for each city from 183 municipal governments’ official websites and news. We constructed a lockdown duration index as the standardised sum of days all city-level lockdown measures were in place. Finally, given that the provincial governments are responsible for designing and implementing local policy for COVID-19, the dispersion of the virus is likely to be determined by numerous province-level factors, including social and geographic proximity to Wuhan, long-run policies effecting socio-spatial vulnerability of communities, virus-preparedness, and the ability to respond (e.g. province-level measures to mitigate the virus outbreak). Hence, we include province-level fixed effects into the model. The results of our regressions are shown in Appendix Table A4. We find that for all three city-level exposure variables (LnCases, Baidu Concern Index and Sentiment Index) a large part of the variation is explained by province fixed effects and the share of immigration from Wuhan during the days prior to the lockdown of Wuhan and the imposition of travel restrictions. With respect to additional city-level factors, population density and GDP per capita are positively, and health expenditure negatively correlated with the Baidu Search Index, long-run air quality and the number of hospitals per capita are both positively associated with the Negative Sentiment Index. Based on this analysis, we include immigration rate, population density, GDP per capita, the number of hospitals, health expenditure and annual average AQI as city-level controls as well as province fixed effects into our main empirical specification, which we discuss next. 4 Empirical strategy and attrition To estimate the effect of virus exposure on social behaviour and economic preferences, we use a generalised Difference-in-Differences Model (DID). It differs from a classic DID model in the sense that the treatment variables in our case are continuous, rather than binary (Wing et al., 2018). Importantly, the panel structure of our data allows us to control for individual unobserved fixed effects and isolate the effects of the exogenous treatment, by comparing the differences before and after the virus outbreak across participants who experienced different levels of exposure to COVID-19. We estimate the following main specification:(1) Ykijt=δExposurej+β3Xjt+ηi+λtdp+εijt where Yijtk is primary outcome k from the experimental modules discussed above for individual i living in city j at time t.Xjt is a vector of city-level controls ; ηi represents unobservable time-invariant individual fixed effects; λtdp represent a province-specific time trend, given that provincial governments’ design and implementation of policies provide sources of variation in city-level exposure to the virus; Exposurej is a continuous variable of being exposed to COVID-19 (City-level cases, Baidu Concern Index, and Sentiment Index) at the time of survey Wave 3 and εijt is the random error term. In this specification, the parameter of interest is the difference-in-differences estimator δ, reflecting the impact on Ykijt from variations in the intensity of treatment in the post-outbreak period (Post). We accommodate for potential serial correlation by estimating clustered standard errors at the individual level. A key assumption underlying the DID identification strategy is the common trends in outcomes between treatment and control groups in absence of a treatment. Whilst this assumption is not directly testable, we are able to test parallel trends before the virus outbreak for outcome variables which were collected in both the October and December 2019 surveys, including an incentivised measure of risk preferences and two measures of well-being (i.e. depression and general health of participants). This is shown graphically in Appendix Fig. A3. We further estimate the difference-in-differences model above using the October and December data on the same three outcome variables as if the outbreak had taken place before the December survey (see Table A5 in the Appendix). Both the visual and formal assessments lead to the conclusion that trends in risk preferences, depression and general health did not differ between treatment and control groups in the months prior to the virus outbreak. For the remaining outcomes that only appear in either the October or December survey, we repeat the same regressions described above using survey data from each corresponding month. The results indicate that pre-outbreak preferences are uncorrelated with future virus-exposure (see Table A6). We conclude from this exercise that the common trends assumption likely holds in the context of our data. We are also able to ascertain that individuals did not differ in their socio-demographic characteristics with respect to the degree of virus exposure. Based on the epidemiological measure of exposure (i.e. the number of cumulative confirmed cases at the city-level on the day of the survey adjusted by population), we report summary statistics of basic characteristics of survey participants between those that were severely exposed (the top tercile of virus prevalence), moderately exposed (the middle tercile) and those that were only mildly exposed (the bottom tercile). See Table A7 in the Appendix. We find broad balance across basic demographics including age, gender, year of study, being the only child (significant at the 5% level, chi2-test) and Hukou registration indicating rural or urban origin of participants. A further concern relates to the potential of differential attrition, which may bias our estimates. Table B1 in Appendix B shows that attrition rates across the three waves in our data as 16% between Waves 1 and 2, 19% between Waves 2 and 3. These rates are comparable to previous research conducted via WeChat surveys (e.g. Chen and Yang, 2019). In Appendix B, we also explore in more detail the patterns of attrition in our data and conduct standard attrition tests. We attempt to address differential attrition in our analysis by applying inverse probability weights (IPW) following Wooldridge (2002). First, we predict the probability (pi) of being observed in all three survey waves by regressing a dummy variable equal to one if an individual did not attrite, on (1) a constant term, (2) the primary treatment variable (LnCases) and (3) a rich set of co-variates measured at baseline for all initially recruited participants. Each individual then receives a weight equal to 1/pi in all regressions in the proceeding analysis. Finally, we address the threat of multiple hypothesis testing and the possibility of false positives by estimating sharpened q-values using the false discovery rate (FDR) procedure (Anderson, 2008, Benjamini, Krieger, Yekutieli, 2006). We calculate FDR adjusted q-values for three sets of p-values across all k-outcomes (including three indices) for each of our three treatment variables. We report both conventional p-values and FDR adjusted q-values in all regression output tables. 5 Results 5.1 Short-term effects We present our main treatment effects based on official COVID-19 infection data. Fig. 4 shows the average treatment effect on the treated estimated following Eq. (1) and corresponding confidence intervals for our incentivised primary outcomes for anti-social behaviour and economic preferences.26 Prior to estimation, all outcomes were standardized (z-scored) on the mean to allow for a comparison of treatment effects in units of standard deviations across different outcomes.Fig. 4 Treatment effects - official COVID-19 infection data. Note: X-axis plots the estimated coefficient for a 1-unit increase in the Log of Cases per million Inhabitants. Significance stars * p<0.01, p<0.05, * p<0.1 based on p-values estimated using cluster-robust standard errors, clustered at the individual level. All models are estimated with IPW to account for differential attrition. Number of observations N = 1044. Fig. 4 Fig. 4 shows the estimated treatment effect of a one-unit increase in the log of city-level cases per million inhabitants. We find that people more exposed to virus appear to become more antisocial. Estimates for pro-social, norm enforcement, risk and time preferences are close to zero and show no statistically detectable difference. However, people more exposed to the virus outbreak appear to become more antisocial. Table 4 provides corresponding difference-in-difference estimates for anti-social behaviour, the only dimension of decision-making which appears to be significantly affected by virus exposure. We observe that the coefficient of interest (post × LnCases) shows a significant relationship between the intensity of the outbreak and all outcomes. Specifically, we find that individuals destroy more of their paired player’s endowment in the Joy of Destruction Game (column 1) and take more in the Take Game without deterrence (column 2). The 0.24 standard deviation increase in destructive behaviour corresponds to an increase of approximately 9 percentage points, which is statistically significant at the 1% significance level. Similarly, we find that more exposed individuals take on average around 7% more of the other player’s endowment (0.22 s.d.). Both results are statistically significant at the 1% significance level and remain significant at the 5% level after adjusting for multiple hypothesis testing. In column (3), we find a slightly smaller effect of virus exposure on taking when there is a risk of being detected (0.18 s.d.). which is statistically significant at the 10% level using conventional p-values, but does not survive multiple hypothesis testing corrections.Table 4 Difference-in-difference analysis: Anti-social behaviour. Table 4 (1) (2) (3) (4) Joy of destruction Take game Take game (det.) Anti-sociality index Panel A Post×LnCases 0.237* 0.222* 0.179* 0.212*** (0.076) (0.081) (0.101) (0.058) [0.014] [0.028] [0.311] [0.005] R2-Within 0.018 0.038 0.036 0.053 Number of Individuals 522 522 522 522 Observations 1044 1044 1044 1044 Note: Difference in differences analysis using fixed effects OLS regressions accounting for attrition using Inverse Probability Weighting (IPW). Standard errors clustered at the individual level in parenthesis. Multiple testing adjusted False Discovery Rate (FDR) q-values in square brackets. Post×LnCases is the interaction of logged number of cumulative confirmed cases at the city-level per million inhabitants officially reported on the date of the third survey with a post-outbreak indicator. All regressions include individual fixed effects, time-varying city-level controls for average immigration rate from Wuhan (20–23 Jan), number of hospitals per million inhabitants, health expenditure as a share of total expenditure, population density, GDP per capita and province-specific time trends. The dependent variable in column (4) is an index for anti-sociality based on the average of the z-scores of all three anti-social outcome variables. * p<0.1, p<0.05, * p<0.01. Finally, we also construct a simple index for anti-social behaviour compromising the choices made in all three games of the anti-social behaviour module.27 Column (4) reports the effects of a unit increase in exposure on the anti-social behaviour index, which confirms our earlier results and show that participants exposed more heavily to the virus significantly increase anti-social behaviours (0.21 s.d.). 5.2 Results based on social media data The following section presents the results of our alternative measures of COVID-19 exposure based on social media data. Panel B in Fig. 5 shows the estimated treatment effect of a one-unit increase in the log of the Baidu Index, which captures city-level concern around COVID-19. Panel C shows the estimated treatment effect of a one standard-deviation unit increase in the Negative Sentiment Index. The latter index, constructed using text-analysis of Sina Micro-blog posts discussing COVID-19, provides a measure of city-level (negative) sentiment. Regression results presenting detailed estimations can be found in the Appendix Tables A8 and A9.Fig. 5 Treatment effects - social media data. Note: X-axis plots the estimated coefficient for a 1-unit increase in the log of the Baidu Index measuring concern about COVID-19 (Panel B) and a 1-unit increase in the Negative Sentiment Index (Sina Weibo) (Panel C). Significance stars * p<0.01, p<0.05, * p<0.1 based on p-values estimated using cluster-robust standard errors, clustered at the individual level. All models are estimated with IPW to account for differential attrition. Number of observations Panel B: N=1044, Panel C: N=1036. Fig. 5 With respect to anti-social behaviour, we observe again a similar yet less pronounced pattern as in the previous section. In Panel B, an increase in city-level concern is associated with a general increase in destructive behaviour (0.28 s.d.), significant at the 5% level. In Panel C, higher levels of negative sentiment led to a general increase in destructive behaviour (0.21 s.d.), significant at the 5% level. However, after adjusting for multiple hypothesis testing, the observed increases in destructive behaviour are no-longer statistically different from zero. The exposure variables based on social media data reveal additional treatment effects, not found when using infection data. First, we find that higher levels of city-level concern (Panel B) are associated with a significant increase (0.21 s.d.) in risk-aversion (at the 5% level, measured using Eckel & Grossmann’s lottery choice task (Risk Aversion – EG). However, FDR adjustments render this finding insignificant. Second, we observe that city-level concern (Panel B) is also associated with a decrease in altruism, which is highly statistically significant at 1% level and remains statistically significant at the 10% level after FDR adjustments. 5.3 Sensitivity analysis We perform additional sensitivity analysis to ensure robustness of the results presented in this section. First, we exclude participants located in Hubei Province (N=10) from the analysis to mitigate the influence of potential outliers. Wuhan, the epicentre of the outbreak and surrounding cities in Hubei province were most severely affected by the virus and reported disproportionally high numbers of cases compared to the rest of China. We find that our results are largely unaffected (see Appendix Fig. A6). Second, another indicator of the COVID-19 epidemic which is usually reported is mortality and thus we control for reported mortality at the city-level. In China, COVID-19 related mortality was largely concentrated in Hubei Province, with 50% of the cities in our dataset reporting zero deaths by the date of the survey. Hence, we believe that mortality does not serve as a good indicator for virus exposure per se. Nonetheless, we add mortality (i.e. the cumulated confirmed cases reported on the date of the third survey at the city level) as a control to our baseline specification. Again, we find that our main results are robust to this specification (see Appendix Fig. A6). Finally, as our study sets itself apart from a number of rapidly emerging COVID-19 papers, relying on post-outbreak data between-subject designs, we test whether our results would be affected by how the impact of COVID-19 is identified. We focus on the following comparison: We use the data collected in March 2020 only and re-estimate Eq. (1) thereby reflecting a between-subject design relying entirely on post-outbreak data and exploiting variations in individual exposure to the virus. This identification has been widely utilised by existing studies reviewed in the Introduction. Although differences are subtle, the results show that we would underestimate the effect of virus exposure on anti-social behaviour, if ignoring individuals’ heterogeneous initial preferences and other time-invariant unobservables (see Appendix Fig. A7). 5.4 Potential pathways The analysis so far has found consistent evidence that COVID-19 exposure leads to an increase in anti-social behaviour. In this section, we explore a range of potential pathways through which exposure to COVID-19 may be associated with anti-social behaviour. We are especially interested in cognitive and psychological well-being, which have found to be important determinants of anti-social behaviour. We utilise variables measured both before and after the outbreak, capturing components of cognitive ability, psychological and physiological well-being. In addition, we construct a measure of virus-specific subjective risk perception using a set of variables elicited in the post-outbreak survey.28 Empirically, we use a triple-difference approach to assess potential pathways by estimating separate regressions for each variable using a fully interacted variant of our main Eq. (1):(2) antisocialit=δ(LnCasesj)+β2(postt×Zit)+θ(postt×LnCasesj×Zit)+Zit+Xijt+ηi+εijt where antisocialit is an index of anti-social behaviour29 ; Zit captures the change in cognitive ability, psychological, physiological well-being or virus risk perception measured only in Wave 3. Xjit now represents a vector of all time-varying control variables and time-fixed effects contained in Eq. (1) as well as their interaction with Zit. In this regression, a positive significant estimate for the triple-difference coefficient θ would suggest that there is a statistically significant difference between individuals who experienced an increase in Zit and those who did not. Table 4 provides an overview of all estimation results from Eq. (2). First, we explore whether effects of COVID-19 exposure vary by subjective virus-risk perception. This is particularly relevant, as the perceived threat of the virus may differ largely between individuals, even if they are exposed to the same number of cases at the city-level. Hence, one might hypothesise that only those individuals with higher subjective risk perception change their behaviour in response to increased objective virus exposure. The triple-difference estimate in Table 5 , column (2) suggests that this may be the case. There is a statistically significant positive difference between individuals with higher subjective risk perception, which points to the importance of how the virus is perceived. However, this difference is only significant at the 5% level and the estimate of δ remains positive and highly statistically significant, which suggests that differences are not fully explained by subjective risk perception.Table 5 Heterogeneous impact of virus exposure by potential mechanism. Table 5 Anti-sociality index (1) (2) (3) (4) (5) (6) (7) Post×LnCases 0.215* 0.213* −0.008 0.192* 0.098 −0.153 0.273 (0.058) (0.059) (0.352) (0.066) (0.072) (0.152) (0.382) Post× Virus Risk ×LnCases 0.137 (0.069) Post× Cognitive Ability ×LnCases −0.034 (0.053) Post× Depletion ×LnCases 0.030* (0.016) Post× Depressive Symptoms ×LnCases 0.460* (0.125) Post× Negative Affect ×LnCases 0.042* (0.015) Post× General Health ×LnCases −0.013 (0.094) R2 0.115 0.204 0.208 0.235 0.208 0.194 0.201 Number of Individuals 522 522 522 522 522 522 522 Observations 1044 1044 1044 1044 1044 1044 1044 Note: Table reports OLS estimates of Eq. (2) where the dependent variable is an index of anti-social behaviour. LnCases is the logged number of confirmed cases at the city-level per million inhabitants reported on the date of the third survey. All triple interaction terms provide estimates for potential heterogeneous effects. Virus-risk Factor is a continuous score of virus-risk perception obtained from a factor analysis of post-outbreak survey responses (score ranges between approximately −2 and 2). All remaining variables were measured both pre and post outbreak: Raven score captures the number of correctly completed puzzles (Score: 0–9, recoded so that a higher score represents less completed puzzles). Depletion is a continuous score for state self-control capacity (Score between −7 and 11: higher score indicating more depletion). Depression is a binary variable that takes the value 1 if an individual has depressive symptoms. Negative affect is a continuous score measuring negative affect (Score: 0–30, higher score indicating higher negative affect); General health is a continuous measure of general health (Likert scale: 1–5, higher score indicating better health). For details on how variables were measured and constructed, see Table A2. * p<0.1, p<0.05, * p<0.01. A large literature in behavioural economics suggests that cognitive capacity and self-control can affect economic and social decision-making (e.g. Carvalho, Meier, Wang, 2016, Friehe, Schildberg-Hörisch, 2017, Mani, Mullainathan, Shafir, Zhao, 2013). We hypothesise that changes in cognitive capacity may interact with higher virus-prevalence. For example, it has been shown that individuals with low self-regulatory resources (i.e. in a state of ego-depletion), feel less guilt and subsequently show less pro-social behaviour (Xu et al., 2012). In columns (3) and (4) we explore two measures of cognitive capacity. We find no statistically significant difference for individuals who perform worse in a set of Raven’s Progressive Matrices (a measure of cognitive ability). We find suggestive evidence of higher anti-social behaviour, significant at the 10% level, for individuals who report higher levels of momentary ego-depletion (evaluated at the time the survey was taken) and hence may have lower self-control capacity. Next, we explore whether mental health may be driving the observed relationship. Emerging research in psychology shows that COVID-19 is likely to have serious consequences on mental health, resulting in increased levels of depression and other mental disorders (Huang, Zhao, 2020, Pfefferbaum, North, 2020, Raker, Zacher, Lowe, 2020, Thombs, Bonardi, Rice, Boruff, Azar, He, Markham, Sun, Wu, Krishnan, Thombs-Vite, Benedetti, 2020). In turn, research in behavioural economics and cognitive science find that depression and negative emotions and mood are able to impair decision-making in more general terms (Gotlib, Joormann, 2010, Haushofer, Cornelisse, Seinstra, Fehr, Joëls, Kalenscher, 2013, De Quidt, Haushofer, Roth, 2018). Based on such previous evidence, we hypothesise that once an individual’s mental health is compromised, he or she may be less likely to care for others and act in a more anti-social manner. In columns (5) and (6) we provide evidence that this might be the case. We find a statistically significant increase in anti-social behaviour for individuals who were subject to greater virus exposure and experienced an increase in depressive symptoms (as measured by the 10-item CESD depression scale) and negative affect (or mood) (measured by the PANAS scale).30 Finally, besides psychological well-being, we also check for the effects of physiological well-being using self-reported health status as an indicator (column 7). We find no statistically significant difference, which leads us to conclude that changes in anti-social behaviour are likely to be driven by a deterioration in mental health. In the following section, we discuss interesting directions for the design of public health interventions to mitigate compromising social behaviour and mental health. 5.5 Limitations The following clarifies important limitations of our sample with respect to attrition and generalizability. In addition, we also address the fact that our study’s time frame is limited to only the pre- and immediate post-outbreak and first lockdown period in China. Therefore, we are only able to provide estimates on the short-term impact of COVID-19 and our results are unable to speak to literature addressing long-term impacts and the effect of multiple lockdowns. One of the major problems with longitudinal studies is attrition by introducing possible bias when participants who drop out of a study are systematically different from those who remain in it. We have taken various steps to deal with this potential concern in our dataset (all additional analysis can be found in Appendix B). Amongst others, we formally test for non-random attrition and find that attrition is unrelated to our treatment variable “city-level COVID-19 cases” yet is related to certain participant characteristics measured at baseline. We address attrition by implementing a separate BGWL test and by applying inverse probability weights to all our regressions. We acknowledge, however, that inverse probability weighting is limited in that it can only address attrition based on observable characteristics, and some attrition might still be non-random. Another caveat is that our study was conducted with a convenience sample of university students from Beijing which is not representative of a more general population sample and therefore our results and suggestions for certain policy interventions should be interpreted considering this specific group. Nonetheless, although university students differ from the general population in certain characteristics (e.g., our sample is significantly younger and better educated and females are overrepresented), other research indicates that student populations exhibit very similar behavioural patterns with respect to social preferences, where university student samples usually provide lower bound estimates of pro-sociality (i.e., they are less altruistic) (Snowberg, Yariv, 2021, Falk, Meier, Zehnder, 2013). Finally, our study focuses on the immediate impact of the COVID-19 outbreak, leveraging data from just before the outbreak of COVID-19 and immediately after the first wave was overcome. We are therefore not able to investigate preferences, perceptions and attitudes over longer periods of time or capture the effects of experiencing multiple lockdowns as other studies are able to (e.g. Harrison, Hofmeyr, Kincaid, Monroe, Ross, Schneider, Swarthout, 2022, Aragon, Bernal, Bosch, Molina, et al.). Noteworthy in the Chinese context is that China has maintained a ‘Zero-Covid’ strategy, which has resulted in multiple large-scale lockdowns since the initial lockdown which we study. Another notable difference to the initial lockdown is that those later, larger and longer lockdowns have also sparked social unrest among residents and university students living under strict lockdown conditions. Some literature focusing on COVID-19 and social unrest highlights an association between increased emotional stress, anxiety and aggression and the incidence of social unrest (Lackner et al., 2021). This also speaks to our results, as we already observe an increase of negative affect and anti-social behaviour after the first lockdown period in China. Finally, we acknowledge, that our results must be interpreted as short term effects, as we are confined to data from before and immediately after the first lock-down. Our findings thus complement research which utilises longitudinal data and multiple surveys over longer time periods after the first lockdown. 6 Discussion and conclusion In this paper, we test whether exposure to the COVID-19 pandemic alters social behaviour and economic preferences of individuals. We exploit a unique experimental panel dataset that enables us to track changes in social behaviour and economic decision-making of the same individuals before and after the COVID-19 outbreak. In order to capture multidimensional responses to the virus outbreak, we construct city-level measures of societal concern and sentiment specific to COVID-19 in addition to standard epidemiological measures of virus exposure (cases per million inhabitants). The novelty of our approach pertains to our within-subject design which controls for unobserved individual characteristics, rich variation in individual exposure to multiple measures of the virus outbreak and the ability to provide insights into the channels transmitting the influence on individual preferences. Our main finding is that greater exposure to COVID-19 causes an increase in anti-social behaviour. This finding contributes to a growing body of literature exploring how preferences respond to traumatic exogenous shocks and stressful situations such as war, conflict and public health crises. We are able to extend this earlier work by considering the acute effect on decision-making during an unfolding crisis and testing potential pathways through which such an event may influence behaviour, in particular mental health. Bauer et al. (2016) note that negative shocks are likely to have a positive legacy on pro-social behaviour in the long-term in terms of cooperation, altruistic giving and civic participation. This is in line with findings from Grimalda et al. (2021) showing that exposure to COVID-19 is associated with increased altruism measured months after the outbreak. In contrast, our findings show that, in the short-term, anti-social behaviour increases. In addition, we show that anxiety reflected by online search behaviour at the onset of the crisis and negative sentiments further undermine altruism. Our findings of increased antisociality and largely stable prosociality contribute to the literature on social preferences and exogenous shocks, which has largely produced mixed evidence. For instance, Branas-Garza et al. (2022) and Buso et al. (2020) find that prosociality decreased during periods of the first Covid-lockdowns. Others, such as Bokern et al. (2021) using data of multiple waves up to one year after the start of the first lockdown, note some short-term fluctuations yet show by large stability of social preferences measured with the help of a solidarity game. Shachat et al. (2021) provides mixed findings with respect to social preferences, showing greater levels of cooperation and lower levels of trust in their sample.31 We also contribute to the literature that examines the stability of risk and time preferences over the course of the COVID-19 outbreak. We find no significant changes in either risk or time preferences caused by exposure to the virus outbreak. Our findings are in line with a number of other studies providing evidence on the intertemporal stability of risk and time preferences (Angrisani, Cipriani, Guarino, Kendall, Ortiz de Zarate, 2020, Harrison, Hofmeyr, Kincaid, Monroe, Ross, Schneider, Swarthout, 2022, Drichoutis, Nayga, 2021, Guenther, Galizzi, Sanders, 2021). Two studies focusing on samples from Wuhan, China provide mixed evidence. Shachat et al. (2021) find increased risk tolerance, while Bu et al. (2020) find decreased risk tolerance in their post-outbreak survey, the latter effect potentially explained by rising pessimistic beliefs rather than changes in general risk preferences. Exploiting within-student changes in preferences, and variation in exposure to the outbreak, Bu et al. (2020) also show that risk taking is irresponsive to the level of virus exposure, which aligns with the findings from our within-subject analysis. In addition to methodological innovations, our research is further able to elucidate the potential mechanisms driving the relationship between COVID-19 exposure and changes in anti-social behaviour. We find that the effect of virus-exposure on anti-social behaviour is most pronounced for those individuals who experienced an increase in depression or in their negative mood, whereas changes in cognitive ability and ego-depletion do not seem to interact with virus exposure. Our results are related to Belot et al. (2020) providing survey evidence from the early phase of the pandemic in China, documenting that younger people are significantly more likely to report negative effects on mental health. That said, our results from a student sample suggest that the effect on anti-social behaviour is likely to be smaller in a general population sample. Nonetheless, we are not able to rule out that alternative mechanisms exist, which are not explored in this paper. For example, economic stressors are often named as a cause of antisocial behaviour (e.g. Schneider et al., 2016). Due to a lack of specific data on individual economic conditions, we are unable to ascertain whether economic uncertainty or financial insecurity interact with increased virus exposure. Nonetheless, we believe economic stressors to be closely related to the emotional well-being pathway, for which we find robust evidence. This finding has important and practical implications for policies designed to tackle major public health crisis events. While most government resources usually focus on mitigating the virus outbreak per se, such as in the form of expanding medical treatment for infected people, our results suggest that interventions to provide psychological support are critical in response to such pandemics. In the context of COVID-19 or similar events, investments should therefore also focus on expanding the supply of consultation with mental health professionals in the form of online and smartphone-based psychological support avenues that can reach a wider audience of potentially affected people. Our evidence suggests that such psychological interventions that aim to promote mental well-being should be initiated from the starting point of a major health crises and not follow much later (Duan and Zhu, 2020).32 In addition to counselling, research from behavioural economics and psychology point out promising light-touch interventions to reduce acute stress and depression and foster pro-social behaviour including the application of mindfulness mediation and mindfulness-based cognitive therapy (Iwamoto, Alexander, Torres, Irwin, Christakis, Nishi, 2020, Kang, Gray, Dovidio, 2014, Leiberg, Klimecki, Singer, 2011, Sun, Yao, Wei, Yu, 2015).33 Promoting and galvanizing socially responsible behaviour has been at the core of many governments’ COVID-19 response and research shows that pro-sociality predicts health behaviours and compliance with public health guidelines (Campos-Mercade et al., 2021).34 Our findings suggest that addressing poor mental health, early on during the crisis, may play an important role in avoiding increases in anti-social behaviour and ensuring wide-scale adherence to public health guidelines. Declaration of Competing Interest Authors declare that they have no conflict of interest. Appendix A Fig. A2.Table A1 Summary of studies on the impact of COVID-19 on economic and social preferences in China. Table A1Paper Population Sample size Same individual over time Time span Games Inc Identification Change Sig Shachat et al. (2021) Students from Wuhan University N=602 across pre- and post COVID-19 samples No (main sample); Yes (sub sample) Baseline: 2019/05; Endline: various samples 01/02/03 2020 Dictator Game; Ultimatum Game; Trust Game; Prisoner’s Dilemma Game; Stag Hunt Game; Risk attitudes (Holt and Laury, 2002); Ambiguity attitudes Yes ($) Main analysis: repeated cross-sectional data (pre-post analysis); Robustness: panel data on sub-sample, N=92 Yes: Prisoner Dilemma [cooperation] (+); Stag Hunt [risky action] (−); Risk aversion in gains (−); Risk tolerance in losses (−); Ambiguity aversion (+) Bu et al. (2020) Students from Wuhan University N=257 Yes (retention 88%) Baseline: 2019/10; Endline: 2020/02 - early 2020/03 Hypothetical allocation to a risky investment; Stated risk aversion (risk attitudes) No Main analysis: heterogenous exposure (Wuhan, Hubai Province or rest of China); Robustness: panel DiD framework Yes: Risk investment (−); Risk aversion (+) Li et al. (2022) Chinese general population N=1872 across pre- and post COVID-19 samples No (pre: 696; post: 1176) Baseline: 2019/9–2019/12; Endline: early 2020/3 Trust game; Risk attitudes (Holt and Laury, 2002); Time preferences Yes ($) Main analysis: repeated cross-sectional data (pre-post analysis) Yes: Trust [−]; Trustworthy [+]; Risk aversion [+]; Impatience [+] Our paper Students from different Beijing universities N=793 Yes (Retention 68%) Baseline: 2019/10 2019/12; Endline: early 2020/03 Joy of Destruction; Take Game; Dictator Game with Third-Party Punishment; Trust Game (hypothetical); Public Good Game (hypothetical); Lottery Choice Task; Investment Game (hypothetical); Time preferences Yes ($), majority of the games Main analysis: heterogenous exposure + panel DiD framework Yes: Joy of destruction (+); Take Game (+) Table A2 Survey modules. Table A2Group Measure Description Variable construct Anti-social Behaviour Joy of Destruction (Abbink and Herrmann, 2011)$23 Binary decision to anonymously destroy a matched player’s endowment as a measure of nastiness. Dummy which takes the value of 1 if the participant decides to destroy another player’s endowment at a cost to him/her-self. Take Game (Schildberg-Hörisch and Strassmair, 2012)$23 Share of endowment taken from a matched player as a measure of theft. Percentage taken from other player’s endowment Take Game with Deterrence (Schildberg-Hörisch and Strassmair, 2012)$23 Share of endowment taken from a matched player with a 40% chance of detection resulting in loss of endowment, as a measure of theft with risk. Percentage taken from other player’s endowment Pro-social Behaviour Dictator Game (Fehr and Fischbacher, 2004)$23 Amount of endowment transferred to a matched player (decision observed by third party). Percentage invested into a public good. Trust game (Berg et al., 1995)13 Share of hypothetical endowment entrusted to a hypothetical player, as a measure of trust. Percentage sent to the other player Public-Goods Game (low return)13 Share of hypothetical endowment contributed towards a public good, as a measure of cooperation in a low and high return scenario. Percentage given to the other player Norm-enforcement Third-party punishment game (Fehr and Fischbacher, 2004)$23 Amount of costly punishment imposed on a matched player based on the amount transferred by the matched player in a dictator game. Binary variable: Takes the value of 1 if a participant is willing to punish when the dictator transfers zero credits to the other player. Extent variable: Amount punished at a cost ratio of 1 Yuan for every 3 Yuan deducted. Risk & Time Preferences CRRA coefficient (Eckel and Grossman, 2002)$123 Choice between six lotteries (50/50 odds) increasing in variance, absolute pay-off and riskiness. Coefficient of relative risk aversion midpoints (CRRA) Risk aversion (Gneezy and Potters, 1997)13 Share of hypothetical endowment not invested in a lottery (50/50 odds). Percentage invested into a lottery Present Bias (Andreoni et al., 2015)$23 Individual β parameter derived from 24 budget lines across 4 timeframes Dummy which takes the value of 1 if present biasedness parameter beta is greater than 1. Time Discounting (Andreoni et al., 2015)$23 Individual δ parameter derived from 24 budget lines across 4 timeframes Discount rate (parameter delta) Cognitive Ability & Well-being Raven’s Standard Progressive Matrices (Bilker et al., 2012)$23 Cognitive ability measured by the number of correctly completed puzzles (out of 9). Score between 0 and 9. Depression (Andresen et al., 1994)123 Depression score calculated using the Centre for Epidemiological Studies Depression Scale Short-form (CESD-10). Continuous variable: Depression score between 0 and 30 (sum of ten items). Binary variable: Takes the value of 1 if depression score is greater than 10. Positive Affect (Thompson, 2007)23 Assessment of mood on the day of the survey using the international Short-form of the Positive and Negative Affect Schedule (PANAS-ISF) Positive affect score between 5 and 25 (sum of five items). Negative Affect (Thompson, 2007)23 Negative affect score between 5 and 25 (sum of five items). Life Satisfaction23 Self-assessed general life satisfaction Likert scale between 1 and 5 Happiness23 Self-assessed general happiness (enjoying life) Likert scale between 1 and 5 Eudaemonic Well-being23 Self-assessed meaningfulness of life Likert scale between 1 and 5 Depletion23 Five-item depletion scale adapted from Twenge et al. (2004). Score between - 7 and + 11 General health123 Self-assessed general health status Likert scale between 1 and 5 Note:$ Incentivised tasks; 13 Included in Survey Wave 1 and 3; 23 Included in Survey Wave 2 and 3; 123 Included in Survey Wave 1, 2 and 3. Table A3 Baidu search terms. Table A3No. English translation 1 Coronavirus disease (pneumonia caused by the novel coronavirus) 2 Novel coronavirus 3 Real-time Situation of COVID-19 4 The Latest News about pneumonia caused by COVID-19 5 The latest news about COVID-19 6 Coronavirus disease outbreak situation 7 Confirmed cases 8 New cases 9 New cases of pneumonia caused by the novel coronavirus 10 N95 masks 11 How often change n95 mask 12 Antibacterial gel 13 What are the symptoms of pneumonia caused by the novel coronavirus 14 Symptoms of the novel coronavirus 15 Symptoms of coronavirus disease (pneumonia caused by the novel coronavirus) 16 Dry cough 17 What is the temperature of COVID-19 18 Is dry cough a symptom of COVID-19 19 Fever clinic 20 Early symptoms of COVID-19 Table A4 Threats to identification - formal assessment. Table A4 LnCases Baidu index Sentiment index (1) (2) (3) (4) (5) (6) Immigration Rate (Wuhan) 0.912* 0.844* 0.450* 0.343* 0.173* 0.196** (0.116) (0.121) (0.091) (0.089) (0.098) (0.097) Population Density 0.088 0.142* −0.036 (0.108) (0.080) (0.087) Number of Hospitals 0.017 −0.024 0.174 (0.065) (0.044) (0.076) Lockdown Duration Index −0.088 −0.045 −0.074 (0.066) (0.060) (0.081) GDP per Capita 0.128 0.179 −0.068 (0.120) (0.075) (0.122) Health Expenditure Share −0.055 −0.074* −0.023 (0.052) (0.038) (0.057) Annual Average AQI −0.067 −0.007 0.224 (0.068) (0.072) (0.096) Constant 3.378* 3.200* 13.316* 13.012* 0.304* 0.312** (0.017) (0.112) (0.013) (0.084) (0.014) (0.140) R2 0.711 0.734 0.443 0.515 0.420 0.473 Province Fixed Effects Yes Yes Yes Yes Yes Yes Observations 183 183 183 183 179 179 Note: Table shows results from simple OLS regressions to assess city-level determinants of virus exposure. Dependent variables are LnCases, Baidu Index and Negative Sentiment Index. LnCases is the logged number of cumulative confirmed cases at the city-level per million inhabitants officially reported on the date of the third survey. Baidu Index is an index of city-level COVID-19 concern based on Baidu search volume indices for 20 virus-related keywords. Sentiment Index is the city-level average share of negative expressed emotions via social media. All explanatory variables are z-scored and all regressions include province fixed effects. Robust standard errors in parentheses. * p<0.1, p<0.05, * p<0.01. Table A5 Difference-in-difference analysis: parallel survey trends October December 2019. Table A5 (1) (2) (3) Risk aversion Depression General health December 2019 0.011 0.624*** −0.140 (0.105) (0.111) (0.146) December 2019 ×LnCases −0.010 −0.039 0.036 (0.035) (0.039) (0.051) Number of Individuals 522 522 522 Waves 2 2 2 Observations 1044 1044 1044 Note: Difference in Difference Analysis using fixed effects OLS regressions to test for pre-outbreak parallel trends between October and December 2019. Dependent variables are standardized (see details of measures in Table A2). LnCases is the logged number of cumulative confirmed cases at the city-level per million inhabitants officially reported on the date of the third survey. December 2019 is a dummy referring to the second survey wave (prior to the virus outbreak). Standard errors in parentheses. * p<0.1, p<0.05, * p<0.01. Table A6 Pre-outbreak exposure analysis. Table A6 (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) Co-op Trust Altruism Punish (Binary) Punish (Extent) Destruction Taking Taking (Det.) Risk taking Present bias Discounting LnCases −0.037 −0.022 −0.049 −0.033 −0.058 −0.049 0.026 0.025 0.059 0.067** 0.062* (0.050) (0.037) (0.039) (0.055) (0.045) (0.030) (0.029) (0.027) (0.036) (0.034) (0.035) R2 0.002 0.001 0.003 0.001 0.005 0.003 0.001 0.001 0.005 0.006 0.008 Observations 522 522 522 522 522 522 522 522 522 513 513 Note: OLS analysis of pre-outbreak exposure. Standard errors clustered at the city level in parenthesis. LnCases is the logged number of cumulative confirmed cases at the city-level per million inhabitants officially reported on the date of the third survey. Table A7 Basic characteristics of participants by exposure tercile. Table A7 Full sample Mildly exposed Moderately exposed Highly exposed P-val Gender 0.82 0.79 0.86 0.81 0.22 Age 19.85 19.73 19.78 20.03 0.23 Year of Study 2.56 2.47 2.58 2.61 0.82 Hukou 0.21 0.24 0.20 0.18 0.35 Only Child 0.64 0.58 0.63 0.73 0.01 Chronic Illness 0.09 0.08 0.09 0.10 0.81 General Health 3.76 3.75 3.75 3.78 0.77 Observations 522.00 179.00 169.00 174.00 . Note: Mild, moderate and high exposure categories are based upon terciles of the number of cumulative confirmed cases at the city-level per million population officially reported on the date of the third survey. Mildly exposed (0–7 Cases per million population), Moderately exposed (8–30 Cases per million population), Highly exposed (>30 Cases per million population). P-val refers to the p-value obtained from tests of equality of means across all three categories of exposure using Anova and proportions using chi2-test. Table A8 Difference-in-difference analysis: anti-social behaviour. Table A8 (1) (2) (3) (4) Joy of destruction Take game Take game (det.) Anti-sociality index Panel A Post×LnCases 0.237* 0.222* 0.179* 0.212* (0.076) (0.081) (0.101) (0.058) [0.014] [0.028] [0.311] [0.005] Panel B Post× Baidu Index 0.301 0.017 0.067 0.128* (0.124) (0.083) (0.114) (0.072) [0.123] [1.000] [1.000] [0.299] Panel C Post× Sentiment Index 0.178** 0.047 0.039 0.088 (0.084) (0.070) (0.089) (0.057) [0.887] [1.000] [1.000] [0.887] Number of Individuals 522 522 522 522 Observations 1044 1044 1044 1044 Note: Difference in differences analysis using fixed effects OLS regressions accounting for attrition using Inverse Probability Weighting (IPW). Standard errors clustered at the individual level in parenthesis. Multiple testing adjusted False Discovery Rate (FDR) q-values in square brackets. Post×LnCases is the interaction of logged number of cumulative confirmed cases at the city-level per million inhabitants officially reported on the date of the third survey with a post-outbreak indicator. Post× Baidu is the interaction of Baidu Search Index with a post-outbreak indicator. Post× Sentiment is the interaction of the Negative Sentiment Index with a post-outbreak indicator. All regressions include individual fixed effects, time-varying city-level controls for average immigration rate from Wuhan (20–23 Jan), number of hospitals per million inhabitants, health expenditure as a share of total expenditure, population density, GDP per capita and province-specific time trends. The dependent variable in column (4) is an index for anti-sociality based on the average of the z-scores of all three anti-social outcome variables. * p<0.1, p<0.05, * p<0.01. Table A9 Difference-in-difference analysis: risk & time preferences. Table A9 (1) (2) (3) (4) Risk aversion Risk taking Present bias Discounting Panel A Post×LnCases 0.074 −0.144 −0.174 −0.082 (0.080) (0.125) (0.124) (0.124) [0.577] [0.549] [0.423] [0.680] Panel B Post× Baidu Index 0.180** 0.066 −0.088 0.054 (0.090) (0.117) (0.141) (0.144) [0.249] [1.000] [1.000] [1.000] Panel C Post× Sentiment Index 0.064 −0.065 0.026 0.221 (0.078) (0.090) (0.124) (0.141) [1.000] [1.000] [1.000] [0.887] Number of Individuals 522 522 522 522 Observations 1044 1044 1044 1044 Note: Difference-in-difference analysis using fixed effects OLS regressions accounting for attrition using Inverse Probability Weighting (IPW). Standard errors clustered at the individual level in parenthesis. Multiple testing adjusted False Discovery Rate (FDR) q-values in square brackets. Post×LnCases is the interaction of logged number of cumulative confirmed cases at the city-level per million inhabitants officially reported on the date of the third survey with a post-outbreak indicator. Post× Baidu is the interaction of Baidu Search Index with a post-outbreak indicator. Post× Sentiment is the interaction of the Negative Sentiment Index with a post-outbreak indicator. All regressions include individual fixed effects, time-varying city-level controls for average immigration rate from Wuhan (20–23 Jan), number of hospitals per million inhabitants, health expenditure as a share of total expenditure, population density, GDP per capita and province-specific time trends. * p<0.1, p<0.05, * p<0.01. Table A10 Difference-in-difference analysis: pro-social behaviour. Table A10 (1) (2) (3) (4) Cooperation Trust Altruism Pro-sociality index Panel A Post×LnCases −0.034 −0.155 0.003 −0.062 (0.112) (0.096) (0.109) (0.059) [0.959] [0.353] [1.000] [0.577] Panel B Post× Baidu Index 0.139 −0.050 −0.283*** −0.065 (0.125) (0.117) (0.099) (0.068) [1.000] [1.000] [0.075] [1.000] Panel C Post× Sentiment Index 0.140 −0.004 −0.002 0.045 (0.088) (0.083) (0.086) (0.051) [0.887] [1.000] [1.000] [1.000] Number of Individuals 522 522 522 522 Observations 1044 1044 1044 1044 Note: Difference in differences analysis using fixed effects OLS regressions accounting for attrition using Inverse Probability Weighting (IPW). Standard errors clustered at the individual level in parenthesis. Multiple testing adjusted False Discovery Rate (FDR) q-values in square brackets. Post×LnCases is the interaction of logged number of cumulative confirmed cases at the city-level per million inhabitants officially reported on the date of the third survey with a post-outbreak indicator. Post× Baidu is the interaction of Baidu Search Index with a post-outbreak indicator. Post× Sentiment is the interaction of the Negative Sentiment Index with a post-outbreak indicator. All regressions include individual fixed effects, time-varying city-level controls for average immigration rate from Wuhan (20–23 Jan), number of hospitals per million inhabitants, health expenditure as a share of total expenditure, population density, GDP per capita and province-specific time trends. The dependent variable in column (4) is an index for pro-sociality based on the average of the z-scores of all three pro-social outcome variables. * p<0.1, p<0.05, * p<0.01. Table A11 Difference-in-difference analysis: norm enforcement behaviour. Table A11 (1) (2) (3) Punishment (Binary) Punishment (Extent) Norm-enforcement index Panel A Post×LnCases 0.070 0.038 0.076 (0.105) (0.099) (0.084) [0.680] [0.947] [0.577] Panel B Post× Baidu Index −0.018 −0.088 −0.041 (0.104) (0.127) (0.104) [1.000] [1.000] [1.000] Panel C Post× Sentiment Index −0.034 −0.026 0.001 (0.096) (0.092) (0.076) [1.000] [1.000] [1.000] Number of Individuals 522 522 522 Observations 1044 1044 1044 Note: Difference in differences analysis using fixed effects OLS regressions accounting for attrition using Inverse Probability Weighting (IPW). Standard errors clustered at the individual level in parenthesis. Multiple testing adjusted False Discovery Rate (FDR) q-values in square brackets. Post×LnCases is the interaction of logged number of cumulative confirmed cases at the city-level per million inhabitants officially reported on the date of the third survey with a post-outbreak indicator. Post× Baidu is the interaction of Baidu Search Index with a post-outbreak indicator. Post× Sentiment is the interaction of the Negative Sentiment Index with a post-outbreak indicator. All regressions include individual fixed effects, time-varying city-level controls for average immigration rate from Wuhan (20–23 Jan), number of hospitals per million inhabitants, health expenditure as a share of total expenditure, population density, GDP per capita and province-specific time trends. The dependent variable in column (3) is an index for norm enforcement based on the average of the z-scores of three punishment decisions (punishment extent if the dictator gives 0, 2 or 4 Yuan). * p<0.1, p<0.05, * p<0.01. Table A12 Mechanism: improvement in mental health. Table A12 Anti-sociality index (1) (2) (3) (4) (5) Post = 1 ×LnCases 0.215*** 0.618 0.024 0.386 −0.157 (0.058) (0.403) (0.430) (0.457) (0.354) Post = 1 × Positive Affect ×LnCases −0.028 (0.029) Post = 1 × Life Satisfaction ×LnCases 0.054 (0.113) Post = 1 × Happiness ×LnCases −0.049 (0.122) Post = 1 × Meaningfulness ×LnCases 0.077 (0.089) R2 0.115 0.207 0.185 0.194 0.202 Number of Individuals 522 522 522 522 522 Observations 1044 1044 1044 1044 1044 Note: This table reports OLS estimates of Eq. (2) where the dependent variable is an index of anti-social behaviour. LnCases is the logged number of confirmed cases at the city-level per million inhabitants reported on the date of the third survey. All triple interaction terms provide estimates for potential mechanisms. * p<0.1, p<0.05, * p<0.01. Table A13 Wave 3 survey data analysis. Table A13 (1) (2) (3) (4) (5) (6) Wash hands Social distancing Stay home Use face mask Avoid touch Virus knowledge index Pro-sociality 0.158** 0.015 0.052 0.043 0.077 0.030 (0.069) (0.046) (0.043) (0.036) (0.096) (0.193) Anti-sociality −0.017 0.070 0.034 0.044 −0.007 −0.099 (0.067) (0.043) (0.045) (0.032) (0.103) (0.210) Norm-enforcement 0.103 −0.073 −0.093 −0.050 0.035 0.050 (0.065) (0.059) (0.062) (0.056) (0.084) (0.157) Observations 522 522 522 522 522 522 Note: This table is based on 18 OLS regressions (all coefficient estimates presented in this table come from individual regressions). Dependent variables are based on individual survey responses to questions on frequency of protective behaviours collected in the third survey and an index of virus-related knowledge. Each OLS regressions includes additional controls for age, gender, a dummy for being an only child, hukou registration, general health status, depression score, risk aversion, a categorical variable for political membership, an index for perceived virus-risk and city fixed effects. * p<0.1, p<0.05, * p<0.01. Fig. A1 Norm-enforcement preferences in pre (December 2019) and post-outbreak waves (March 2020). Fig. A1 Fig. A2 Frequency distribution of sample exposure to COVID-19. Note: Exposure measured as the logged number of cumulative confirmed city-level cases per million inhabitants on the date of the third survey (Panel A) and Baidu Search Index (Panel B) and Negative Sentiment Index (Panel C). Fig. A2 Fig. A3 Pre-trend visual assessment on survey outcomes. Note: Plots show change in Risk aversion measured via the CRRA interval midpoints from a lottery choice task, Depression measured using the Centre for Epidemiological Studies Depression Scale Short-form (CESD-10) and General health assessed via self-reported health condition between wave 1 and wave 2 of the panel survey. Both surveys took place prior to the outbreak of COVID-19. Fig. A3 Fig. A4 Treatment effects - official COVID-19 infection data. Note: X-axis plots the estimated coefficient for a 1-unit increase in the Log of Cases per million Inhabitants. Significance stars * p<0.01, p<0.05, * p<0.1 based on p-values estimated using cluster-robust standard errors, clustered at the individual level. All models are estimated with IPW to account for differential attrition. Number of observations N = 1044. Fig. A4 Fig. A5 Treatment effects - social media data. Note: X-axis plots the estimated coefficient for a 1-unit increase in the log of the Baidu Index measuring concern about COVID-19 (Panel B) and a 1-unit increase in the Negative Sentiment Index (Sina Weibo) (Panel C). Significance stars * p<0.01, p<0.05, * p<0.1 based on p-values estimated using cluster-robust standard errors, clustered at the individual level. All models are estimated with IPW to account for differential attrition. Number of observations Panel B: N=1044, Panel C: N=1036. Fig. A5 Fig. A6 Sensitivity analysis. Note: Panel A: Treatment effects when Hubei Province participants (10 individuals) are excluded from the analysis (Number of Individuals N=512). Panel B: Treatment effects when city-level Mortality is entered as a control (Number of Individuals N=522). X axis plots the estimated coefficient for a 1-unit increase in the Log of Cases per million population. Significance stars (* p<0.01, p<0.05, * p<0.1) based on p-values estimated using cluster-robust standard errors, clustered at the individual level. Individual regression result tables are available upon request. Fig. A6 Fig. A7 Comparing Estimates from simple OLS (Post-outbreak data only) and the preferred DID model in Eq. (1). Fig. A7 Appendix B Data collection & attrition The experiment was initially designed as a two-wave experiment, with data collection taking place in October and December 2019. The short survey administered in October (Wave 1) was used to build an initial subject pool, with the objective to collect socio-demographic information and key preference measures relevant to our original research question. This information allowed us to implement a stratified randomisation procedure prior to Wave 2. In March 2020 we re-contacted all students from the original subject pool with a follow-up survey (Wave 3), designed around the new objective to assess the stability of preferences after COVID-19. In all three waves, the entire data collection was conducted via the Chinese messaging app WeChat. Research Assistants were trained to contact students via WeChat, send survey links on pre-specified dates and administer payment directly to participants’ WeChat Wallets. Due to the lack of reliable and trustworthy online crowdsourcing platforms in China (such as Amazon MTurk or Prolific), using WeChat is a common procedure to maintain student subject pools for research purposes. However, one can expect high levels of attrition with this form of data collection (see e.g. Chen and Yang, 2019). To minimise attrition, the original study design included an additional prize-draw for ten 100Y bonus payments, for which participants were eligible only if they completed both initial survey waves (1 and 2). For Wave 3, no such incentive was possible. From the initial sample (N=793) recruited in October 2019, we exclude 3 individuals for which no city location is available, 4 individuals who live in Hong Kong, Macau and Taiwan, and 15 individuals who completed Waves 1 and 3, but skipped Wave 2 (the main experimental survey in the pre-outbreak period). The remaining sample of 771 individuals serves as our starting point for the following attrition analysis. Table B1 shows the number of participants in each wave, the number of attrited individuals as well as the share of attrition for each survey wave. As attrition poses a potential threat to producing unbiased estimation results, the analysis below will carefully consider the potential impact of attrition.Table B1 Attrition share across survey waves. Table B1Wave Participants Attrition Attrition share 1 771 2 646 125 16.21% 3 522 124 19.20% Table B1 shows that attrition rates are high across the three waves in our data (16% between Wave 1 and 2, 19% between Wave 2 and 3), however, comparable to previous research conducted via WeChat surveys. First, we explore the patterns of attrition in our data by comparing attritors vs. the non-attritors using a rich set of sociodemographic characteristics, heath indicators and economic preferences collected at baseline (Wave 1). We further explore city-level variables (representative of the respondents’ hometown) as well as city-level confirmed cumulative cases (log-transformed) reported in the respondents’ hometown on 14th March 2020, our primary treatment variable. Tables B2 and B3 present the results from this exercise for attrition between Waves 1 and 2 and 2 and 3, respectively. Columns (1) and (2) show the means of both attrition and non-attrition samples columns (3) and (4) report the difference in means and a p-value derived from a t-test for the equality of means. In Table B2 we first focus on attrition that occurred between Waves 1 and 2.Table B2 Difference between attrited and non-attrited: wave 1 to 2. Table B2 (1) (2) (3) (4) Variable Non-attritors Attritors Difference p-value LnCases 2.607 2.633 0.026 (0.816) Pay-off (Wave 1) 26.296 21.376 −4.920* (0.003) Cooperation 4,487.288 4,337.112 −150.176 (0.638) Trust 48.260 47.728 −0.532 (0.831) Risk Aversion 3.009 2.988 −0.021 (0.940) Risk Taking 7,805.771 7,990.112 184.341 (0.670) Age 19.920 20.488 0.568* (0.001) Female 0.774 0.704 −0.070* (0.092) Rural Hukou 0.204 0.232 0.028 (0.487) Only Child 0.655 0.664 0.009 (0.843) General Health 3.771 3.632 −0.139* (0.097) Depression Score 9.065 10.096 1.031 (0.047) Economics Major 0.455 0.600 0.145* (0.003) Chronic Illness 0.091 0.104 0.013 (0.656) Perseverance 2.532 2.552 0.020 (0.751) Prosocial Trait 0.221 0.208 −0.013 (0.741) Competitiveness 12.673 11.376 −1.297*** (0.001) Immigration Rate (Wuhan) 0.497 0.568 0.071 (0.167) Hospitals (City) 30.615 30.634 0.019 (0.991) GDP per Capita (City) 90.283 84.338 −5.945 (0.181) Health Expenditure Share (City) 0.077 0.081 0.004 (0.167) Observations 646 125 771 * p<0.1, p<0.05, * p<0.01. Table B3 Difference between attrited and non-attrited: wave 2 to 3. Table B3 (1) (2) (3) (4) Variable Non-Attritors Attritors Difference p-value LnCases 2.596 2.654 0.059 (0.590) Pay-off (Wave 1) 26.205 26.677 0.472 (0.795) Pay-off (Wave 2) 32.518 29.390 −3.127 (0.157) Pay-off Difference (W1-W2) 6.313 2.713 −3.600 (0.215) Cooperation 4,472.960 4,547.605 74.645 (0.817) Trust 48.056 49.121 1.065 (0.675) Risk Aversion 3.008 2.687 −0.321 (0.257) Risk Taking 7,605.580 8,648.508 1,042.928** (0.015) Altruism 3.939 3.774 −0.165 (0.632) Punishment (Binary) 0.588 0.573 −0.016 (0.753) Punishment (Extent) 2.103 2.081 −0.023 (0.923) Destruction 0.157 0.145 −0.012 (0.742) Taking 9.983 11.089 1.106* (0.079) Taking (Deterrence) 9.362 10.500 1.138* (0.095) Age 19.849 20.218 0.369 (0.017) Female 0.818 0.589 −0.229* (0.000) Rural Hukou 0.207 0.194 −0.013 (0.741) Only Child 0.644 0.702 0.058 (0.223) General Health 3.699 3.653 −0.046 (0.575) Depression Score 12.153 13.097 0.944* (0.088) Economics Major 0.443 0.508 0.066 (0.188) Chronic Illness 0.088 0.105 0.017 (0.562) Perseverance 2.522 2.573 0.051 (0.438) Prosocial Trait 0.230 0.185 −0.044 (0.285) Competitiveness 12.795 12.161 −0.634 (0.125) Raven Score 6.548 6.137 −0.411*** (0.006) Sleep Quality 7.739 7.597 −0.143 (0.364) Life Satisfaction 3.404 3.331 −0.074 (0.438) Immigration Rate (Wuhan) 0.485 0.545 0.059 (0.224) Hospitals (City) 30.530 30.975 0.446 (0.801) GDP per Capita (City) 90.826 87.998 −2.828 (0.538) Health Expenditure Share (City) 0.076 0.077 0.001 (0.768) Observations 522 124 646 * p<0.1, p<0.05, * p<0.01. Statistically significant differences in means of attritors and non-attritors show that there are systematic attrition patterns between the first two survey waves. With respect to sociodemographic characteristics, we observe that individuals who are older, identify as male, major in economics, revealed a lower willingness to compete and earned less in the baseline survey are all more likely to leave the sample at Wave 2. With respect to health variables, individuals with a higher depression scores and a lower general health score are significantly more likely to attrite. In Table B3 we focus on attrition that occurred between Waves 2 and 3. In addition to the individual sociodemographic characteristics, health variables and city-level variables observed at baseline, we further include variables measured in Wave 2. These variables include our main outcome measures of anti-social and norm-enforcement behaviour as well as additional subjective well-being and health indicators. Here we see that older participants and men are significantly more likely to be in the attrition sample. Attritors are less risk-averse and show slightly more anti-social behaviour in the Take-Game. Individuals with higher depression scores and lower cognitive ability are more likely to attrite. Following Fitzgerald et al. (1998) we formally test for non-random attrition in the data. Specifically, we explore whether the observable individual- and city-level characteristics are associated with a greater probability of leaving the sample. To do so, we regress an attrition indicator, equal to 1 for attrited individuals and zero otherwise, on the full set of variables measured in the initial survey waves shown in Tables B2 and B3. If attrition is random, the estimated parameters will not be statistically different from zero. Results are shown in Table B4 . The dependent variable in column (1) captures attrition at either Wave 2 or 3. The results indicate that our primary treatment variable (city-level COVID-19 cases) is unrelated to attrition, which shows that attrition is exogenous to treatment (i.e., exposure). However, the analysis confirms that attrition is significantly associated with certain baseline characteristics, which suggests that attrition is non-random and warrants further investigation into potential selection bias.Table B4 Attrition probit. Table B4 (1) Attrition any wave LnCases 0.040 (0.079) Pay-off (Wave 1) −0.005 (0.003) Cooperation −0.000 (0.000) Trust −0.001 (0.002) Risk Aversion −0.004 (0.017) Risk Taking 0.000 (0.000) Age 0.102* (0.028) Female −0.537* (0.112) Rural Hukou 0.013 (0.141) Only Child 0.177 (0.123) General Health −0.001 (0.063) Depression Score 0.012 (0.010) Economics Major 0.281* (0.099) Chronic Illness 0.094 (0.176) Perseverance 0.100 (0.077) Prosocial Trait −0.122 (0.121) Competitiveness −0.030 (0.013) Immigration Rate (Wuhan) 0.067 (0.144) Hospitals (City) 0.002 (0.003) GDP per Capita (City) −0.002 (0.002) Health Expenditure Share (City) 0.933 (1.760) Constant −2.361*** (0.788) Observations 771 * p<0.1, p<0.05, * p<0.01. In the presence of non-random attrition, a second standard procedure is to assess whether attrition is ignorable. To do so, we implement the BGLW (Becketti et al., 1988) test which assesses whether attrition is statistically associated with our main dependent variables. The BGLW test involves regressing an outcome variable from the initial wave on a set of explanatory variables, an attrition dummy (capturing future attrition), and the attrition dummy interacted with the other explanatory variables. An F-test of the joint significance of the attrition dummy and the interaction variables can help to determine whether the explanatory variables differ systematically between non-attrited and attrited households. We implement the BGLW test for outcomes measured in both Waves 1 and 2, using the attrition dummy from the previous attrition test and its interaction with individual characteristics and city-level variables as the predictors. We reject the null hypothesis of no difference between attrited and non-attrited for only two of 12 outcomes, namely the Trust Game (Wave 1) and our measure of Altruism (Wave 2). Although we find no pervasive evidence that attrition is non-ignorable, differential attrition may still pose a threat to statistical inference from our analysis. In an attempt to adjust for differential attrition, we use the inverse probability weighting (IPW) technique, following the procedure outlined in Wooldridge, 2002, Wooldridge, 2007. The key assumption of IPW methods is that by conditioning on a set of observed covariates, the complete-population density of an outcome of interest can be derived by weighting the conditional density by the inverse selection probabilities (Fitzgerald et al., 1998). We use the full set of individual and city-level characteristics observable at baseline (Wave 1), shown in column (3) of Table B4, to predict the probability (pi) that an individual will be observed in all three survey waves. Each individual receives a weight equal to 1/pi, giving more weight to participants who are similar on baseline observables to those individuals who did not stay in the sample at Waves 2 or 3. We apply the IPW to all model estimates throughout the analysis. Supplementary material Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.jebo.2022.12.007 Appendix C Supplementary materials Supplementary Data S1 Supplementary Raw Research Data. This is open data under the CC BY license http://creativecommons.org/licenses/by/4.0/ Supplementary Data S1 Data availability Data will be made available on request. Acknowledgements We thank the seminar participants at CEENRG for very helpful comments. We are indebted to our research assistants for supporting the execution of the experiments. Financial support from the UK's 10.13039/501100000269 Economic and Social Research Council (ESRC), the Faculty of Economics and Statistics, University of Innsbruck, the Department of Land Economy, University of Cambridge and Corpus Christi College, Cambridge is gratefully acknowledged. Jing You acknowledges the 10.13039/501100012226 Fundamental Research Funds for the Central Universities , and the Research Funds of 10.13039/501100004260 Renmin University of China (Grant No.: 19XNB019). 1 The authors are not making an assertion as to the global origin of the specific virus, but simply that within China, Wuhan municipal Center for Disease Control and Prevention (CDC) released the first epidemiological alert of 27 cases on 31 December 2019. 2 See, for instance, Andrabi and Das (2017); Becchetti et al. (2014); Brown et al. (2019); Callen (2015); Cassar, Grosjean, Whitt, 2013, Cassar, Grosjean, Whitt, Cassar, Healy, von Kessler, 2017; Cohn et al. (2015); Falco and Vieider (2018); Filipski et al. (2019); Fleming et al. (2014); Grosjean (2014); Hanaoka et al. (2018); Page et al. (2014); Said et al. (2015); Voors et al. (2012). 3 See, for instance, Aksoy and Palma (2019); Cahlíková and Cingl (2017); Cahlikova et al. (2019); Cettolin et al. (2019); Delaney et al. (2014); Fehr et al. (2019); Haushofer et al. (2013); Kettlewell (2019); Koppel et al. (2017); Prediger et al. (2014). 4 We acknowledge that the majority of Covid cases were concentrated in Wuhan during the first Wave of the pandemic in China. Our findings thus complement those of Shachat et al. (2021) and Bu et al. (2020) by exploiting the wider geographic dispersion in our data. Moreover, comparing only the extremely high prevalence rate in Wuhan against zero otherwise could potentially exacerbate the variance of the “intervention” and, thus, the estimated “treatment” effect of COVID-19. The wider geographic coverage of our sample is able to reduce this upward bias. This point, that empirical regularities in the far tails of the distribution tend to disappear, has been re-illustrated recently by Hamermesh and Leigh (2022). 5 Notably, many governments have designed their response to COVID-19 around the premise that people are able and willing to engage in pro-social behaviour. The UK’s slogan ‘Stay Home, Protect the NHS, Save Lives’ (and other similar informational campaigns in other countries) directly conveys an underlying appeal to pro-social behaviour. In contrast, the Chinese government has largely drawn on wartime rhetoric to enforce strict containment and lockdown policies. 6 We acknowledge that it is often criticised that student samples do not accurately represent the overall population. However, there is increasing evidence that student samples are appropriate for studying human social behaviour (Exadaktylos, Espín, Brañas Garza, 2013, Falk, Meier, Zehnder, 2013). In addition, we argue that in the case of COVID-19 response, this is a particularly important demographic. Students are subject to a lower risk of suffering severe medical consequences of infection, however, mitigating the spread of the virus relies heavily on low-risk demographics to follow public health guidelines and engage in social distancing. Hence, we believe that studying students’ behaviour is highly relevant in the context of COVID-19. 7 Note that Waves 1 and 2 of the experiment were initially designed and collected as part of a pre-registered experiment on economic decision-making and air pollution. Details at: https://doi.org/10.1257/rct.4856-1.0 8 While incentivization is the norm for preference elicitation in experimental economics in order to reduce hypothetical bias, we would like to highlight recent results by Hackethal et al. (2022) which suggest that hypothetical bias is rather limited when eliciting risk preferences in online experiments – a setting very similar to ours. Nonetheless, previous literature provides no clear indication if the results of Hackethal et al. (2022) can be extended to social preference elicitation (Engel, 2011, Gillis, Hettler, 2007, Camerer, Mobbs, 2017). 9 Note that participants at no point were provided feedback about the (payoff) outcomes of the different experimental tasks they completed. By doing so, we can exclude learning effects or strategic behaviour of participants, which could potentially bias our results. 10 We acknowledge that if a task was chosen in which participants were assigned to multiple roles, we applied a ‘Pay One’ payment procedure, i.e., we randomly draw one role of that task for payment. Such a procedure has been shown to eliminate hedging opportunities and also wealth effects (e.g. Bardsley et al., 2009) 11 Previous literature indicates that even hypothetical incentives in economic experiments can give accurate results (e.g. Gillis and Hettler, 2007) 12 For more details find the English translation of the instructions in Appendix C. 13 To calculate the mid-points, we first replaced the infinity value for the lower bound with −1 and for the upper bound with 10. 14 While the theory of ego-depletion is very prevalent in the psychology literature, more recently, it has also attracted attention in economics and there is a growing number of studies which have assessed the impact of self-control depletion on economic preferences (Achtziger, Alós-Ferrer, Wagner, 2016, Achtziger, Alós-Ferrer, Wagner, 2018, Gerhardt, Schildberg-Hörisch, Willrodt, 2017). 15 The following five items were used: “I feel drained”, “I feel calm and rational”, “I feel lazy”, “I feel sharp and focused” and “I feel like my willpower is gone”. Responses were given on a 5-point Likert scale ranging from 1 “not true” to 5 “very true”. 16 For our analysis, we selected to explore sanctioning behaviour for the most unequal distribution (i.e., dictator giving nothing to the recipient). We also observe punishment decisions for each of the alternative transfer amounts (2, 4, 6, 8 and 10 Yuan) and now provide a descriptive overview Appendix Fig. A1. For robustness, we additionally explore sanctioning behaviour to enforce a 50/50 distribution norm based on the amount participants were willing to punish if the dictator transferred half of their endowment (i.e., 10 Yuan). Our results are robust to this analysis. 17 We acknowledge that a greater proportion of participants in our sample are female (80%). This is due to the fact that around 70% of our sample come from liberal arts colleges/universities where the share of female students constitutes on average more than 60% with the highest share being at 98%. However, related research on preferences and the COVID-19 pandemic in China does not suggest a significant heterogeneity in results by gender Bu et al. (2020). The gender bias of our sample should therefore not preclude a valid interpretation of the presented findings. 18 Lu et al. (2018) have utilised this exogenously determined admission rule to study the impact of students’ experiences in competitive college admissions on their risk preferences. 19 Admittedly, there are different measures of exposure that one can consider. We primarily use the number of confirmed infections or cases to measure exposure, which is heavily used in the epidemiological literature to model epidemic spread (e.g. Zhao and Chen, 2020) and well-accepted in the economics literature to investigate the effects of epidemics and pandemics on economic outcomes (Aksoy, Eichengreen, Saka, 2020, Flückiger, Ludwig, Önder, 2019, Gonzalez-Torres, Esposito, 2020). An alternative measure is mortality and number of deaths. While mortality has been used as a measure of severity in papers assessing the long-term effects of a pandemic such as the Spanish flu (Aassve, Alfani, Gandolfi, Moglie, Adda, 2016, Karlsson, Nilsson, Pichler, 2014), it is not practical for assessing short-term effects due to its little variability at the onset of a pandemic. Epidemiological measures may however not fully capture the extent of exposure to the virus nor the general social ‘concern’ or ‘sentiment’ about the epidemic at the time. For robustness purposes we, thus, also use two alternative measures of exposure that capture these dimensions based on internet and social media data. 20 We use a log-transformation of COVID-19 confirmed cases to deal with skewed data due to the over proportionally large amount of cases reported in Wuhan City and Hubei province where some of our participants were located. 21 A popular view is that an authoritarian regime censors social media. We believe that Chinese social media data provides a particularly interesting and valid source of expressed opinion in China. First, social media is not necessarily censored in an authoritarian regime, as the government can also use it as propaganda or surveillance tools (Qin et al., 2017). Second, the COVID-19 outbreak is a public health crisis and is less sensitive than a political event for the purpose of censorship of public opinions. Third, Sina microblog has been widely used as a reliable tool to analyse and track sentiment dynamics, psychological well-being, public knowledge and opinions, as well as a range of other attitudes towards public issues (e.g. air pollution in Zheng et al., 2019 and COVID-19 Han, Lam, Li, Guo, Zhang, Li, Chen, Chen, Zhang, Pang, Chen, 2020, Li). 22 There are typically two terms in Chinese education system – autumn and spring terms. The former consists of 17–20 weeks starting from early September till the Chinese New Year. The term dates are pre-determined and released before each academic year in September. The Term dates were not altered on account of the pandemic. 23 For example, people would migrate out of cities in response to rising risk of adverse events (Brown et al., 2019). 24 For example, some of our sample universities also required students to report their locations and health information on a daily basis. Mobility out of their current city has been forbidden. 25 The city-level factors are the 2018 data compiled from provincial statistical yearbooks. The AQI is an index of air quality consisting of six key pollutants from 1436 air monitoring stations across 338 cities, having been set up by the Ministry of Ecology and Environment since 2012. We calculate the annual average AQI for each city based on daily AQI readings between 2015 and 2019. 26 All regressions are estimated using all participants who took part in all 3 survey waves (N=522). Note that 15 individuals were excluded from the original sample (N=539), who had not completed all three surveys. Additionally, one individual from Macau and one individual from Hong Kong were removed from the sampled due to unavailability of data for control variables. Individual beta parameters could not be estimated for 9 individuals. This resulted in models for present bias to be estimated with 513 individuals and all other models estimated with 522 individuals. The full results of each regression can be found in Appendix Tables A8–A11. A visualisation of treatment effects for all outcome variables is provided in Figs. A4 and A5. 27 The Anti-sociality index is an average of z-scores of Destruction, Taking and Taking with deterrence. The index construction follows Kling et al. (2007). 28 Specifically, we asked respondents to indicate, on a 10-point Likert Scale, the perceived level of risk/threat posed by the virus to (1) themselves, (2) their family and (3) society as a whole. This provides a measure of emotional risk perception. We further asked respondents how they perceived the level of infections at their current location and whether any of their friends or family had been infected with the virus, which captures cognitive risk perception. As all five variables are highly correlated, we conduct a factor analysis to predict an underlying ‘Virus-Risk Factor’ for each individual. 29 The index is constructed by calculating the average of z-scores of the three tasks of the anti-social behaviour module following Kling et al. (2007). 30 We also assess whether changes in other dimensions of psychological well-being including happiness and positive mood interact with virus-prevalence. We find no statistically significant difference in anti-social behaviour for individuals with increased positive affect (on the date of the survey), self-assessed happiness, meaningfulness of life and life satisfaction (see Table A12 in the Appendix). 31 We acknowledge that our experimental approach holds many similarities to Shachat et al. (2021), but there are also some notable differences with respect to research design and identification strategy, including the use of a within- instead of between-subject design, additional survey data to study potential mechanisms and a more nuanced analysis with respect to exposure to the virus outbreak through ample geographical variation in virus prevalence. Note that the main sample difference to Shachat et al. (2021) and Bu et al. (2020) is that both studies heavily draw on students located in Hubei province where the majority of COVID-19 cases were reported, while our study relies on geographical variation in student’s location with only few students having been located in Hubei. 32 The advantage of online consulting is that it can be efficiently scaled at low cost and at the same time there is evidence of the effectiveness of digitally provided psychotherapy when compared to face-to-face therapy, in particular when treating acute symptoms of stress and depression (Andersson, Cuijpers, Carlbring, Riper, Hedman, 2014, Barak, Hen, Boniel-Nissim, Shapira, 2008, Carlbring, Andersson, Cuijpers, Riper, Hedman-Lagerlöf, 2018). 33 Again, this intervention has been shown to be effective when delivered online (Spijkerman et al., 2016) and thus lends itself for large-scale application during COVID-19 or similar events. 34 We also assess whether social behaviour correlates with self-reported compliance with protective behaviour and knowledge related to the virus. Exact wording of the questions can be found in Appendix C. We find little to no correlation between our indices of pro-sociality, anti-sociality and norm-enforcement and protective behaviour as well as virus knowledge. This, however, is likely caused by a lack of variation in compliance with protective behaviour, with overall compliance being overwhelmingly high amongst our sample population. Regression results are presented in Table A13 in the Appendix. ==== Refs References Aassve, A., Alfani, G., Gandolfi, F., Moglie, M. L., 2020. Epidemics and Trust: The Case of the Spanish Flu. NBER Working Paper. Abbink K. Herrmann B. The moral costs of nastiness Econ. Inq. 49 2 2011 631 633 10.1111/j.1465-7295.2010.00309.x Achtziger A. Alós-Ferrer C. Wagner A.K. The impact of self-control depletion on social preferences in the ultimatum game J. Econ. Psychol. 53 2016 1 16 10.1016/j.joep.2015.12.005 Achtziger A. Alós-Ferrer C. Wagner A.K. Social preferences and self-control J. Behav. Exp. Econ. 74 April 2018 161 166 10.1016/j.socec.2018.04.009 Adda J. Economic activity and the spread of viral diseases: evidence from high frequency data Q. J. Econ. 53 2016 891 941 10.1093/qje/qjw005 Aksoy B. Palma M.A. The effects of scarcity on cheating and in-group favoritism J. Econ. Behav. Organ. 165 2019 100 117 10.1016/j.jebo.2019.06.024 Aksoy C.G. Eichengreen B. Saka O. Revenge of the experts: will COVID-19 renew or diminish public trust in science? SSRN Electron. J. 2020 1 17 10.2139/ssrn.3617825 Alsharawy A. Ball S. Smith A. Spoon R. Fear of COVID-19 changes economic preferences: evidence from a repeated cross-sectional MTurk survey J. Econ. Sci. Assoc. 7 2 2021 103 119 10.1007/s40881-021-00111-x Anderson M.L. Multiple inference and gender differences in the effects of early intervention: a reevaluation of the abecedarian, perry preschool, and early training projects J. Am. Stat. Assoc. 103 484 2008 1481 1495 10.1198/016214508000000841 Andersson G. Cuijpers P. Carlbring P. Riper H. Hedman E. Guided internet-based vs. face-to-face cognitive behavior therapy for psychiatric and somatic disorders: a systematic review and meta-analysis World Psychiatry 13 2014 288 295 10.1080/16506073.2017.1401115 25273302 Andrabi T. Das J. In aid we trust: hearts and minds and the Pakistan earthquake of 2005 Rev. Econ. Stat. 99 3 2017 371 386 10.1162/REST_a_00638 Andreoni J. Kuhn M.A. Sprenger C. Measuring time preferences: a comparison of experimental methods J. Econ. Behav. Organ. 116 2015 451 464 10.1016/j.jebo.2015.05.018 Andresen E.M. Malmgren J.A. Carter W.B. Patrick D.L. Screening for depression in well older adults: evaluation of a short form of the CES-D Am. J. Prev. Med. 10 2 1994 77 84 10.1016/s0749-3797(18)30622-6 8037935 Angrisani M. Cipriani M. Guarino A. Kendall R. Ortiz de Zarate J. Risk preferences at the time of COVID-19: an experiment with professional traders and students SSRN Electron. J. 927 2020 10.2139/ssrn.3609586 Aragon, F., Bernal, N., Bosch, M., Molina, O., et al., 2022. COVID-19 and economic preferences: evidence from a panel of cab drivers. Barak A. Hen L. Boniel-Nissim M. Shapira N. A comprehensive review and a meta-analysis of the effectiveness of internet-based psychotherapeutic interventions J. Technol. Hum. Serv. 26 2–4 2008 109 160 10.1080/15228830802094429 Bardsley N. Cubitt R. Loomes G. Moffatt P. Starmer C. Sugden R. Experimental Economics Experimental Economics 2009 Princeton University Press Bauer M. Blattman C. Henrich J. Miguel E. Mitts T. Can war foster cooperation? J. Econ. Perspect. 30 3 2016 249 274 Baumeister R.F. Bratslavsky E. Muraven M. Tice D.M. Ego depletion: is the active self a limited resource? J. Pers. Soc. Psychol. 74 5 1998 1252 1265 10.1037/0022-3514.74.5.1252 9599441 Becchetti L. Conzo G. Conzo P. Salustri F. Understanding the heterogeneity of adverse COVID-19 outcomes: the role of poor quality of air and lockdown decisions SSRN Electron. J. 2020 10.2139/ssrn.3572548 Becchetti L. Conzo P. Romeo A. Violence, trust, and trustworthiness: evidence from a Nairobi slum Oxf. Econ. Pap. 66 1 2014 283 305 10.1093/oep/gpt008 Becketti S. Gould W. Lillard L. Welch F. The panel study of income dynamics after fourteen years: an evaluation J. Labor Econ. 6 4 1988 472 492 Belot, M., Choi, S., Jamison, J. C., Papageorge, N. W., Tripodi, E., Van den Broek-Altenburg, E., 2020. Six-country survey on COVID-19. Benjamini Y. Krieger A.M. Yekutieli D. Adaptive linear step-up procedures that control the false discovery rate Biometrika 93 3 2006 491 507 Berg, J., Dickhaut, J., McCabe, K., 1995. Trust, reciprocity, and social history. doi:10.1006/game.1995.1027 Bilker W.B. Hansen J.A. Brensinger C.M. Richard J. Gur R.E. Gur R.C. Development of abbreviated nine-item forms of the Raven’s standard progressive matrices test Assessment 19 3 2012 354 369 10.1177/1073191112446655 22605785 Böhm R. Betsch C. Korn L. Selfish-rational non-vaccination: experimental evidence from an interactive vaccination game J. Econ. Behav. Organ. 131 2016 183 195 10.1016/j.jebo.2015.11.008 Bokern, P., Linde, J., Riedl, A., Werner, P., 2021. The effect of the COVID-19 crisis on economic and social preferences. Branas-Garza P. Jorrat D.A. Alfonso A. Espin A. García T. Kovarik J. Exposure to the COVID-19 pandemic and generosity R. Soc. Open Sci. 2022 10.31234/osf.io/6ktuz Brown R. Montalva V. Thomas D. Velásquez A. Impact of violent crime on risk aversion: evidence from the mexican drug war Rev. Econ. Stat. 101 5 2019 892 904 10.1162/rest_a_00788 Bu D. Hanspal T. Liao Y. Liu Y. Risk taking during a global crisis: evidence from Wuhan Covid Econ. 5 2020 106 146 Buso I.M. De Caprariis S. Di Cagno D. Ferrari L. Larocca V. Marazzi F. Panaccione L. Spadoni L. The effects of COVID-19 lockdown on fairness and cooperation: evidence from a lablike experiment Econ. Lett. 196 2020 109577 10.1016/j.econlet.2020.109577 32981994 Cahlíková J. Cingl L. Risk preferences under acute stress Exp. Econ. 20 1 2017 209 236 10.1007/s10683-016-9482-3 Cahlikova J. Cingl L. Levely I.V. How stress affects performance and competitiveness across gender Manag. Sci. 2019 10.1287/mnsc.2019.3400 Callen M. Catastrophes and time preference: evidence from the Indian ocean earthquake J. Econ. Behav. Organ. 118 2015 199 214 10.1016/j.jebo.2015.02.019 Camerer C. Mobbs D. Differences in behavior and brain activity during hypothetical and real choices Trends Cogn. Sci. 21 1 2017 46 56 27979604 Campos-Mercade P. Meier A.N. Schneider F.H. Wengström E. Prosociality predicts health behaviors during the COVID-19 pandemic J. Public Econ. 195 2021 104367 33531719 Carlbring P. Andersson G. Cuijpers P. Riper H. Hedman-Lagerlöf E. Internet-based vs. face-to-face cognitive behavior therapy for psychiatric and somatic disorders: an updated systematic review and meta-analysis Cogn. Behav. Ther. 47 1 2018 1 18 10.1080/16506073.2017.1401115 29215315 Carvalho B.L.S. Meier S. Wang S.W. Poverty and economic decision-making : evidence from changes in financial resources at payday Am. Econ. Rev. 106 2 2016 260 284 28003681 Cassar A. Grosjean P. Whitt S. Legacies of violence: trust and market development J. Econ. Growth 18 3 2013 285 318 10.1007/s10887-013-9091-3 Cassar, A., Grosjean, P., Whitt, S., 2014. Social preferences of ex-combatants: survey and experimental evidence from postwar Tajikistan. Economics of Conflict: Theory and Empricial Evidence, 231–262. doi:10.7551/mitpress/9729.003.0012 Cassar A. Healy A. von Kessler C. Trust, risk, and time preferences after a natural disaster: experimental evidence from Thailand World Dev. 94 2017 90 105 10.1016/j.worlddev.2016.12.042 Cettolin E. Dalton P.S. Kop W.J. Zhang W. Cortisol meets GARP: the effect of stress on economic rationality Exp. Econ. 2019 10.1007/s10683-019-09624-z 0123456789 Chapman G.B. Coups E.J. Time preferences and preventive health behavior: acceptance of the influenza vaccine Med. Decis. Mak. 19 3 1999 307 314 10.1177/0272989X9901900309 Chen Y. Yang D.Y. The impact of media censorship: 1984 or brave new world? Am. Econ. Rev. 109 6 2019 2294 2332 Chuang Y. Schechter L. Stability of experimental and survey measures of risk, time, and social preferences: a review and some new results J. Dev. Econ. 117 2015 151 170 10.1016/j.jdeveco.2015.07.008 30078930 Cohn A. Engelmann J. Fehr E. Maréchal M.A. Evidence for countercyclical risk aversion: an experiment with financial professionals Am. Econ. Rev. 105 2 2015 860 885 10.1257/aer.20131314 De Quidt J. Haushofer J. Roth C. Measuring and bounding experimenter demand Am. Econ. Rev. 108 11 2018 3266 3302 10.1257/aer.20171330 Delaney, L., Fink, G., Harmon, C., 2014. Effects of stress on economic decision-making: evidence from laboratory experiments. IZA Discussion Paper (8060). http://ssrn.com/abstract=2420705. Dong D. Xu X. Xu W. Xie J. The relationship between the actual level of air pollution and residents’ concern about air pollution: evidence from Shanghai, China Int. J. Environ. Res. Public Health 16 23 2019 10.3390/ijerph16234784 Dong L. Bouey J. Public mental health crisis during COVID-19 pandemic, China Emerg. Infect. Dis. 26 7 2020 1616 32202993 Drichoutis A.C. Nayga R.M. On the Stability of Risk and Time Preferences Amid the COVID-19 Pandemic 2021 Springer US 10.1007/s10683-021-09727-6 0123456789 Duan L. Zhu G. Psychological interventions for people affected by the COVID-19 epidemic Lancet Psychiatry 7 4 2020 300 302 10.1016/S2215-0366(20)30073-0 32085840 Eckel C.C. Grossman P.J. Sex differences and statistical stereotyping in attitudes toward financial risk Evol. Hum. Behav. 23 4 2002 281 295 10.1016/S1090-5138(02)00097-1 Engel C. Dictator games: a meta study Exp. Econ. 14 4 2011 583 610 Exadaktylos F. Espín A.M. Brañas Garza P. Experimental subjects are not different Sci. Rep. 3 2013 1 6 10.1038/srep01213 Di Falco S. Vieider F.M. Environmental adaptation of risk preferences Econ. J. 132 648 2022 2737 2766 Falk A. Meier S. Zehnder C. Do lab experiments misrepresent social preferences? The case of self-selected student samples J. Eur. Econ. Assoc. 11 4 2013 839 852 10.1111/jeea.12019 Fehr, D., Fink, G., Jack, K., 2019. Poverty, Seasonal Scarcity and Exchange Asymmetries. Fehr E. Fischbacher U. Third-party punishment and social norms Evol. Hum. Behav. 25 2 2004 63 87 10.1016/S1090-5138(04)00005-4 Filipski M. Jin L. Zhang X. Chen K. Living like there’s no tomorrow: the psychological effects of an earthquake on savings and spending behavior Eur. Econ. Rev. 116 2019 107 128 10.1016/j.euroecorev.2019.04.004 Fisman R. Jakiela P. Kariv S. How did distributional preferences change during the great recession? J. Public Econ. 128 2015 84 95 10.1016/j.jpubeco.2015.06.001 Fitzgerald J. Gottschalk P. Moffitt R. An Analysis of Sample Attrition in Panel data: The Michigan Panel Study of Income Dynamics Technical Report 1998 National Bureau of Economic Research Fleming D.A. Chong A. Bejarano H.D. Trust and reciprocity in the aftermath of natural disasters J. Dev. Stud. 50 11 2014 1482 1493 10.1080/00220388.2014.936395 Flückiger M. Ludwig M. Önder A.S. Ebola and state legitimacy Econ. J. 129 621 2019 2064 2089 10.1111/ecoj.12638 Friehe T. Schildberg-Hörisch H. Self-control and crime revisited: disentangling the effect of self-control on risk taking and antisocial behavior Int. Rev. Law Econ. 49 264 2017 23 32 10.1016/j.irle.2016.11.001 Fritsche I. Jugert P. The consequences of economic threat for motivated social cognition and action Curr. Opin. Psychol. 18 2017 31 36 10.1016/j.copsyc.2017.07.027 29221509 Galizzi M.M. Miraldo M. Are you what you eat? Healthy behaviour and risk preferences B.E. J. Econ. Anal. Policy 17 1 2017 10.1515/bejeap-2016-0081 Gao R. Hao B. Li H. Gao Y. Zhu T. Developing simplified chinese psychological linguistic analysis dictionary for microblog Brain and Health Informatics 2013 Springer International Publishing Cham 359 368 Gerhardt H. Schildberg-Hörisch H. Willrodt J. Does self-control depletion affect risk attitudes? Eur. Econ. Rev. 100 2017 463 487 10.1016/j.euroecorev.2017.09.004 Gillis M.T. Hettler P.L. Hypothetical and real incentives in the ultimatum game and Andreoni’s public goods game: an experimental study East. Econ. J. 33 4 2007 491 510 Gneezy U. Potters J. An experiment on risk taking and evaluation periods Q. J. Econ. 112 2 1997 631 645 10.1162/003355397555217 Gonzalez-Torres A. Esposito E. Epidemics and conflict: evidence from the ebola outbreak in western Africa SSRN Electron. J. 2020 10.2139/ssrn.3544606 Gotlib I.H. Joormann J. Cognition and depression: current status and future directions Annu. Rev. Clin. Psychol. April 27 6 2010 285 312 10.1146/annurev.clinpsy.121208.131305 Grimalda G. Buchan N.R. Ozturk O.D. Pinate A.C. Urso G. Brewer M.B. Exposure to COVID-19 is associated with increased altruism, particularly at the local level Sci. Rep. 11 1 2021 1 14 10.1038/s41598-021-97234-2 33414495 Grosjean P. Conflict and social and political preferences: evidence from world war II and civil conflict in 35 European countries Comp. Econ. Stud. 56 3 2014 424 451 10.1057/ces.2014.2 Guenther B. Galizzi M.M. Sanders J.G. Heterogeneity in risk-taking during the COVID-19 pandemic: evidence from the UK lockdown Front. Psychol. 12 April 2021 1 15 10.3389/fpsyg.2021.643653 Hackethal A. Kirchler M. Laudenbach C. Razen M. Weber A. On the role of monetary incentives in risk preference elicitation experiments J. Risk Uncertain. 2022 1 25 10.1007/s11166-022-09377-w Hamermesh D.S. Leigh A.K. “Beauty too rich for use”: billionaires’ assets and attractiveness Labour Econ. 76 2022 102153 Han, Y., Lam, J. C. K., Li, V. O. K., Guo, P., Zhang, Q., 2020. The effects of outdoor air pollution concentrations and lockdowns on COVID-19 infections in Wuhan and other provincial capitals in China (March), 1–7. doi:10.20944/preprints202003.0364.v1 Hanaoka C. Shigeoka H. Watanabe Y. Do risk preferences change ? Evidence from panel data before and after the great east Japan earthquake Am. Econ. J. 10 2 2018 298 330 10.1257/app.20170048 Harrison G.W. Hofmeyr A. Kincaid H. Monroe B. Ross D. Schneider M. Swarthout J.T. Subjective beliefs and economic preferences during the COVID-19 pandemic Exp. Econ. 2022 10.1007/s10683-021-09738-3 0123456789 Haushofer J. Cornelisse S. Seinstra M. Fehr E. Joëls M. Kalenscher T. No effects of psychosocial stress on intertemporal choice PLoS One 8 11 2013 10.1371/journal.pone.0078597 He G. Chen Y. Chen B. Wang H. Shen L. Liu L. Suolang D. Zhang B. Ju G. Zhang L. Du S. Jiang X. Pan Y. Min Z. Using the Baidu search index to predict the incidence of HIV/AIDS in China Sci. Rep. 8 1 2018 1 10 10.1038/s41598-018-27413-1 29311619 Holt C.A. Laury S.K. Risk aversion and incentive effects American economic review 92 5 2002 1644 1655 Huang Y. Zhao N. Generalized anxiety disorder, depressive symptoms and sleep quality during COVID-19 outbreak in China: a web-based cross-sectional survey Psychiatry Res. 288 April 2020 112954 10.1016/j.psychres.2020.112954 32325383 Iwamoto S.K. Alexander M. Torres M. Irwin M.R. Christakis N.A. Nishi A. Mindfulness meditation activates altruism Sci. Rep. 10 1 2020 1 7 10.1038/s41598-020-62652-1 31913322 Kang Y. Gray J.R. Dovidio J.F. The nondiscriminating heart: lovingkindness meditation training decreases implicit intergroup bias J. Exp. Psychol. 143 3 2014 1306 1313 10.1037/a0034150 Karlsson M. Nilsson T. Pichler S. The impact of the 1918 Spanish flu epidemic on economic performance in Sweden. An investigation into the consequences of an extraordinary mortality shock J. Health Econ. 36 1 2014 1 19 10.1016/j.jhealeco.2014.03.005 24721206 Kettlewell N. Risk preference dynamics around life events J. Econ. Behav. Organ. 162 2019 66 84 10.1016/j.jebo.2019.04.018 Kling J. Liebman J. Katz L. Experimental analysis of neighborhood effects Econometrica 75 1 2007 83 119 Koppel L. Andersson D. Morrison I. Posadzy K. Västfjäll D. Tinghög G. The effect of acute pain on risky and intertemporal choice Exp. Econ. 20 4 2017 878 893 10.1007/s10683-017-9515-6 29151807 Kraemer M.U.G. Yang C.H. Gutierrez B. Wu C.H. Klein B. Pigott D.M. du Plessis L. Faria N.R. Li R. Hanage W.P. Brownstein J.S. Layan M. Vespignani A. Tian H. Dye C. Pybus O.G. Scarpino S.V. The effect of human mobility and control measures on the COVID-19 epidemic in China Science (New York, N.Y.) 497 May 2020 493 497 10.1126/science.abb4218 Lackner, M., Sunde, U., Winter-Ebmer, R., 2021. COVID-19 and the forces behind social unrest. Leiberg S. Klimecki O. Singer T. Short-term compassion training increases prosocial behavior in a newly developed prosocial game PLoS One 6 3 2011 10.1371/journal.pone.0017798 Li C. Chen L.J. Chen X. Zhang M. Pang C.P. Chen H. Retrospective analysis of the possibility of predicting the COVID-19 outbreak from internet searches and social media data, china, 2020 Eurosurveillance 25 10 2020 1 5 10.2807/1560-7917.ES.2020.25.10.2000199 Li, K. K., 2020. How Does the COVID-19 Outbreak Affect People’ s Expectation about the Macroeconomy ? Li, K. K., Huang, B., Tam, T., Hong, Y.-y., 2020b. Does the COVID-19 pandemic affect people’s social and economic preferences? Evidence from China. Evidence from China (July 6, 2020). Li K.K. Ying-yi H. Huang B. Tam T. Social preferences before and after the onset of the COVID-19 pandemic in China Judgment and Decision Making 17 6 2022 1313 Li Z. Liu T. Zhu G. Lin H. Zhang Y. He J. Deng A. Peng Z. Xiao J. Rutherford S. Xie R. Zeng W. Li X. Ma W. Dengue Baidu search index data can improve the prediction of local dengue epidemic: a case study in Guangzhou, China PLoS Negl. Trop. Dis. 11 3 2017 e0005354 10.1371/journal.pntd.0005354 28263988 Liu S. Yang L. Zhang C. Xiang Y.-T. Liu Z. Hu S. Zhang B. Online mental health services in China during the COVID-19 outbreak Lancet Psychiatry 7 4 2020 e17 e18 32085841 Lu Y. Shi X. Zhong S. Competitive experience and gender difference in risk preference, trust preference and academic performance: evidence from Gaokao in China J. Comp. Econ. 46 4 2018 1388 1410 10.1016/j.jce.2018.05.002 Mani A. Mullainathan S. Shafir E. Zhao J. Poverty impedes cognitive function Science 341 6149 2013 976 980 10.1126/science.1238041 23990553 Müller S. Rau H.A. Economic preferences and compliance in the social stress test of the COVID-19 crisis J. Public Econ. 194 2021 104322 35702336 Nikolov, P., Pape, A., Tonguc, O., Williams, C., 2020. Predictors of social distancing and mask-wearing behavior: panel survey in seven US states. arXiv preprint arXiv:2009.13103 Page L. Savage D.A. Torgler B. Variation in risk seeking behaviour following large losses: a natural experiment Eur. Econ. Rev. 71 2014 121 131 10.1016/j.euroecorev.2014.04.009 Pennebaker J.W. King L.A. Linguistic styles: language use as an individual difference J. Pers. Soc. Psychol. 77 6 1999 1296 1312 10.1037/0022-3514.77.6.1296 10626371 Pfefferbaum B. North C.S. Mental health and the COVID-19 pandemic N. Engl. J. Med. 2020 1 2 10.1056/NEJMp2008017 Pluchino, A., Inturri, G., Rapisarda, A., Biondo, A. E., Moli, R. L., Zappala’, C., Giuffrida, N., Russo, G., Latora, V., 2020. A Novel Methodology for Epidemic Risk Assessment: the case of COVID-19 outbreak in Italy. http://arxiv.org/abs/2004.02739. Prediger S. Vollan B. Herrmann B. Resource scarcity and antisocial behavior J. Public Econ. 119 2014 1 9 10.1016/j.jpubeco.2014.07.007 Qin B. Strömberg D. Wu Y. Why does China allow freer social media? Protests versus surveillance and propaganda J. Econ. Perspect. 31 1 2017 117 140 10.1257/jep.31.1.117 Raker E.J. Zacher M. Lowe S.R. Lessons from Hurricane Katrina for predicting the indirect health consequences of the COVID-19 pandemic Proc. Natl. Acad. Sci. 117 23 2020 202006706 10.1073/pnas.2006706117 Said F. Afzal U. Turner G. Risk taking and risk learning after a rare event: evidence from a field experiment in Pakistan J. Econ. Behav. Organ. 118 2015 167 183 10.1016/j.jebo.2015.03.001 Schildberg-Hörisch H. Strassmair C. An experimental test of the deterrence hypothesis J. Law, Econ., Organ. 28 3 2012 447 459 10.1093/jleo/ewq015 Schneider D. Harknett K. McLanahan S. Intimate partner violence in the great recession Demography 53 2 2016 471 505 10.1007/s13524-016-0462-1 27003136 Shachat J. Walker M.J. Wei L. How the onset of the COVID-19 pandemic impacted pro-social behaviour and individual preferences: experimental evidence from China J. Econ. Behav. Organ. 190 2021 480 494 34642514 Snowberg E. Yariv L. Testing the waters: behavior across participant pools Am. Econ. Rev. 111 2 2021 687 719 Solnit R. A Paradise Built in Hell: The Extraordinary Communities That Arise in Disaster 2010 Penguin Spijkerman M.P.J. Pots W.T.M. Bohlmeijer E.T. Effectiveness of online mindfulness-based interventions in improving mental health: a review and meta-analysis of randomised controlled trials Clin. Psychol. Rev. 45 2016 102 114 10.1016/j.cpr.2016.03.009 27111302 Steinert S. Corona and value change. the role of social media and emotional contagion Ethics Inf. Technol. 2020 10.1007/s10676-020-09545-z (0123456789) Sun S. Yao Z. Wei J. Yu R. Calm and smart? A selective review of meditation effects on decision making Front. Psychol. 6 July 2015 10.3389/fpsyg.2015.01059 Sutter M. Kocher M.G. Daniela G.R. Trautmann S.T. Impatience and uncertainty: experimental decisions predict adolescents’ field behavior Am. Econ. Rev. 103 1 2013 510 531 10.1257/aer.103.1.510 Thombs B.D. Bonardi O. Rice D.B. Boruff J.T. Azar M. He C. Markham S. Sun Y. Wu Y. Krishnan A. Thombs-Vite I. Benedetti A. Curating evidence on mental health during COVID-19: a living systematic review J. Psychosom. Res. January 2020 10.1016/j.jpsychores.2020.110113 Thompson E.R. Development and validation of an internationally reliable short-form of the positive and negative affect schedule (PANAS) J. Cross-Cultural Psychol. 38 2 2007 227 242 10.1177/0022022106297301 Twenge J.M. Muraven M. Tice D.M. Measuring State Self-Control: Reliability, Validity, and Correlations with Physical and Psychological Stress Unpublished Manuscript 2004 San Diego State University Voors M.J. Nillesen E.E.M. Verwimp P. Bulte E.H. Lensink R. Van Soest D.P. Violent conflict and behavior: a field experiment in Burundi Am. Econ. Rev. 102 2 2012 941 964 10.1257/aer.102.2.941 Wing C. Simon K. Bello-Gomez R.A. Designing difference in difference studies: best practices for public health policy research Annu. Rev. Public Health 39 1 2018 453 469 10.1146/annurev-publhealth-040617-013507 29328877 Wooldridge J.M. Inverse probability weighted m-estimators for sample selection, attrition, and stratification Portuguese Econ. J. 1 2 2002 117 139 Wooldridge J.M. Inverse probability weighted estimation for general missing data problems J. Econom. 141 2 2007 1281 1301 Xiong, H., Liu, J., Huang, J., Huang, S., An, H., Kang, Q., Li, Y., Dou, D., Wang, H., 2020. Understanding the collective responses of populations to the COVID-19 pandemic in Mainland China. medRxiv, 2020.04.20.20068676 http://medrxiv.org/content/early/2020/04/24/2020.04.20.20068676.abstract. 10.1101/2020.04.20.20068676 Xu H. Bègue L. Bushman B.J. Too fatigued to care: ego depletion, guilt, and prosocial behavior J. Exp. Soc. Psychol. 48 5 2012 1183 1186 10.1016/j.jesp.2012.03.007 Yuan Q. Nsoesie E.O. Lv B. Peng G. Chunara R. Brownstein J.S. Monitoring influenza epidemics in China with search query from Baidu PLoS One 8 5 2013 10.1371/journal.pone.0064323 Zhao S. Chen H. Modeling the epidemic dynamics and control of COVID-19 outbreak in China Quant. Biol. 8 1 2020 11 19 10.1007/s40484-020-0199-0 32219006 Zheng S. Wang J. Sun C. Zhang X. Kahn M.E. Air pollution lowers Chinese urbanites’ expressed happiness on social media Nat. Hum. Behav. 3 March 2019 10.1038/s41562-018-0521-2
PMC009xxxxxx/PMC9760614.txt	==== Front J Econ Behav Organ J Econ Behav Organ Journal of Economic Behavior & Organization 0167-2681 0167-2681 Elsevier B.V. S0167-2681(22)00453-X 10.1016/j.jebo.2022.12.010 Article Trust, social protection, and compliance: Moral hazard in Latin America during the COVID-19 pandemic Bird Matthew D. ⁎ Arispe Samuel Muñoz Paula Freier Luisa Feline Universidad del Pacífico, Lima, Peru ⁎ Corresponding author. 19 12 2022 2 2023 19 12 2022 206 279295 2 2 2022 11 12 2022 16 12 2022 © 2022 Elsevier B.V. All rights reserved. 2022 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Political trust is an important predictor of compliance with government policies, especially in the face of natural disasters or public health emergencies. During the COVID-19 pandemic, for example, multiple studies related political trust to increased compliance with mobility restrictions. Yet these findings come mostly from high-income countries where political trust and wealth correlate positively. In Latin America, both variables correlate negatively, allowing for better testing of competing explanations. Using a difference-in-differences design, we find that in Latin America wealth and, counterintuitively, low political trust predict increased compliance. To understand mechanisms, we decompose political trust and wealth into underlying predictors (social protection, corruption, and education) and reinsert them into the model. While education, as a wealth proxy, predicts decreased mobility across all periods, social protection, which was the strongest predictor of political trust, relates significantly to increased mobility, but only at the beginning of the lockdown prior to distribution of emergency support. This suggests the existence of a public health moral hazard early in the pandemic, whereby citizens who benefited previously from government benefits may have been more risk tolerant in the face of the COVID-19 threat. We interpret these findings within the context of the region's recent “inclusionary turn.” Future studies should explore the distinct relationships between political trust, risk perception, and compliance, especially in low- and middle-income countries, and their implications for policy responses to national emergencies. Keywords Trust Compliance Social protection COVID-19 ==== Body pmc1 Introduction Understanding citizen responses to government policies is critical for crafting strategies to enhance collective welfare, especially in the face of natural disasters or public health emergencies. At the start of the COVID-19 pandemic, for example, mobility restrictions were intended as temporary measures to mitigate virus spread and give health systems time to prepare for the expected rise in cases. Yet compliance required citizens to trade off economic activity for physical health. Although emergency social protection policies were created to offset economic harm and decrease the cost of staying at home (Gentilini et al., 2020), we still observed within and between country variation in compliance with mobility restrictions. One explanation offered for compliance in high-income countries is differing levels of pro-sociality, be it civic capital (Barrios et al., 2020; Durante et al., 2021) or trust in politicians (Bargain and Aminjonov, 2020a), science (Eichengreen et al., 2021; Bicchieri et al., 2020; Plohl and Musil, 2021; Brzezinski et al., 2020), or the press (Brodeur et al., 2020).1 In Singapore, however, the relationship between government trust and compliance may have also created a moral hazard whereby citizens with higher levels of political trust were more risk tolerant and less careful about social distancing because of faith in the government's ability to manage the crisis (Wong and Jensen, 2020; Wachinger et al., 2012). Furthermore, we lack evidence to establish the external validity of these findings outside of high-income settings. An alternative explanation of compliance, applied more readily to low- and middle-income countries (LMICs), acknowledges that economic constraints hinder the ability to adhere to stay-at-home orders because of the lack of resources to smooth consumption (Ravallion, 2020; Robalino, 2020) or less opportunity to perform remunerative work at home (Dingel and Neiman, 2020; Garrote et al., 2020). While there is a positive relationship between wealth and compliance in the United States (Wright et al., 2020) and globally (Bargain and Aminjonov, 2020b; Aminjonov et al., 2021), the ex ante positive correlation between education (and other socioeconomic proxies) and political trust in high-income countries may hinder causal comparison of these two competing explanations. In LMICs, such as those in Latin America, a negative correlation exists between political trust and socioeconomic proxies (Hakhverdian and Mayne, 2012), thus enabling better testing of the two major explanations of compliance. This study examines the role of political trust and wealth in citizen compliance with government mobility restrictions in Latin America during the COVID-19 pandemic. We employ a difference-in-differences (DD) design, like that used by Bargain and Aminjonov (2020a), henceforth BA, in their analysis of political trust and compliance across 233 regions (19 countries) in Europe between March and April 2020. BA found that ex ante political trust predicted variation in region-level compliance as measured by Google mobility data. Similarly, we use data from the annual Latin America Public Opinion Project survey (LAPOP, 2019), Google mobility (Google LLC, 2021), and the Oxford COVID-19 Government Response Tracker (OxCGRT) (Hale et al., 2022) to compare trust, wealth, and other underlying explanations of compliance with mobility restrictions across 282 regions (15 countries) in Latin America. We find that the relationship between political trust and compliance during COVID-19 is different than in high-income countries because of the distinct ex ante relationships with government services across socioeconomic gradients. In Latin America, political trust predicted less compliance (more mobility), unlike in high-income countries. This relationship holds when controlling for epidemiological factors, mask mandates, and socio-demographic variables, including age and labor formality. When adding wealth to the model, it predicted increased compliance (less mobility), with the negative effect of political trust outweighing the positive effect of wealth during the period after lockdown until early April. Yet by June 2020, the magnitudes of the effects of political trust had waned, while the impact of wealth, especially for workplace mobility, remained consistent and significant throughout, highlighting two distinct mechanisms affecting compliance. These results contradict findings from high-income countries and may appear counterintuitive, suggesting alternative channels through which trust affects compliance in LMICs. To explore these channels, we began with a stepwise procedure to identify underlying predictors of political trust and wealth. In line with the literature, we found links to education, social protection, and corruption, measured as experience with police bribes. We then replaced political trust and wealth with these variables and implemented a new DD analysis. For the first two weeks after lockdown, having benefited from social protection before the pandemic predicted increased mobility. Since emergency transfers and other protection schemes took longer to implement, we rule out the direct effect of government transfers on mobility immediately after lockdown (Gentilini et al., 2020), though we cannot discard the anticipatory effect of the government's announcement of support on compliance. Regardless, the effects of social protection began to fade after the first two weeks. Having benefited from government services may thus help explain the initial and large negative effects of political trust in the original model. Meanwhile, results for education replicated those of wealth, predicting increased compliance throughout. As for corruption, there was some evidence that having experienced bribes was related to increased workplace mobility two weeks after the lockdown, though the effect reversed the longer mobility restrictions were in place and became marginally significant. One interpretation of these results aligns with findings from studies of natural disasters which predict that high political trust can decrease risk perception, which in turn reduces individual protective actions (Wachinger et al., 2012). In Latin America, political trust driven by increased social protection may have created a public health moral hazard whereby beneficiary citizens were more risk tolerant, especially during the first two weeks of the lockdown period when (i) governments announced but had not yet disbursed social support and (ii) information uncertainty about the virus was greatest. As the lockdown continued, socioeconomic variables (e.g., wealth or education) became more predictive because economic constraints hindered sustained compliance, despite emergency support from governments. Finally, previous experience with bribes may have initially contributed to decreased compliance because of a lack of respect for government authority and later increased compliance because of the inconsistent enforcement of mobility restrictions, which could have made citizens more susceptible to bribe requests when leaving the home. We argue that our results are grounded in the Latin America's “inclusionary turn” (Kapiszewski et al., 2021), in which the region became a global pioneer in cash transfer programs both before and during the pandemic, although it remains an open question whether the generous nature of Latin America's social protection programs may have unintentionally spurred increased mobility or contributed to it, given that the region registered the globe's highest per capita case and mortality rates (Ritchie and Ortiz-Ospina, 2021). Despite some cross-country evidence of the effects of income supports on decreased mobility (Aminjonov et al., 2021), more focused randomized evaluations of the impact of emergency cash transfers in Peru (Bird et al., 2023) and Kenya (Brooks et al., 2022) in the first months of the pandemic suggest that support may have also stimulated small business activity and thus could have made recipient households more mobile and vulnerable to contagion and death. This study makes contributions on two levels. First, it adds to our evolving understanding of citizen responses to the unprecedented government actions taken during the COVID-19 pandemic. While political trust and civic norms predicted compliance to COVID-19 shelter-in-place and social distancing policies across and within high-income countries (Bargain and Aminjonov, 2020a; Allcott et al., 2020; Barrios et al., 2020; Bazzi et al., 2021), the result does not hold among middle-income countries in Latin America, even when controlling for wealth and other covariates.2 Rather, these findings lend more robust support to the paradox of trust hypothesis (Wachinger et al., 2012) initially observed in Singapore (Wong and Jensen, 2020). While political trust increases compliance in some contexts, it may create a moral hazard in others, a possibility acknowledged for natural disasters but not fully recognized in the public health compliance literature (Van de Weerd et al., 2011; Blair et al., 2017; Vinck et al., 2019; Christensen et al., 2020). More broadly, these results contribute to our general understanding of trust and compliance (Letki, 2006; Marien and Werner, 2018) by demonstrating the importance of taking into account welfare state configurations. For example, previous work indicates that the relationship between political trust and welfare spending among European countries resembles that of “twin peaks,” whereby two distinct mechanisms drive welfare spending in high-trust versus low-trust countries in Europe (Algan et al., 2016). In low-trust European countries, welfare spending is large because “uncivic” people expect to free ride or benefit without assuming their share of the cost. In high-trust European countries, “civic” people may support high taxes and benefits expansion when they are surrounded by other high-trust citizens. Likewise, our findings suggest that political trust and compliance among high-income versus low- and middle-income countries may operate differently based on distinct ex ante relationships with government services across socioeconomic gradients. More studies could explore this hypothesis. Our findings are robust to different estimation models, including controls and measures of mobility, trust, and wealth (see Supplemental Material). Regardless, the region-level mobility data prevent us from testing the individual-level relationships between mobility, political trust, wealth, social protection, and corruption experiences. Though suggestive evidence is offered, we were also not able to test more directly whether political trust driven by social protection experiences fostered a public health moral hazard after the initial lockdown. Data permitting, future studies could examine these individual-level relationships. The rest of this paper is organized as follows. Section 2 contextualizes trust dynamics in Latin America compared to high-income countries. Section 3 introduces the data and Section 4 describes the empirical approach. Section 5 shares the main results, while Section 6 explores mechanisms. Section 7 concludes. 2 Political trust in Latin America Social and political trust are related but distinct constructs. Social trust runs along a particularized (i.e., people you know and people like you) to generalized (i.e., people you come across) continuum (Delhey et al., 2011; Newton et al., 2018). As for political trust, it includes two components. The first is institutional trust, which refers to confidence one has in supposedly impartial government entities like the police or courts. The second is trust in political actors, such as the president/prime minister, cabinet, or congress/parliament (Zmerli and Newton, 2017). Global cross-country evidence indicates that particularized social trust forms the foundation for generalized trust, and the latter is a basis for the formation of political trust (Newton and Zmerli., 2011). The relationship between particularized and generalized trust is visible when mapping results from 77 countries using the World Values Survey (see Fig. 1 ). Notably, most Latin American countries sit in the bottom left quadrant (low particularized and low generalized trust) while European countries are located in the top right quadrant (high particularized and high generalized trust). A pattern is also seen for Eastern and Southern European countries located lower on the regression line, while Northern European countries sit at the top.3 Relatedly, Latin America has consistently registered among the lowest levels of political trust in the world (Catterberg and Moreno, 2006; Bargsted et al., 2017; Mattes and Moreno, 2018; Letki, 2018).Fig. 1 Generalized and particularized Trust in Europe and Latin America. Fig 1Source: World Value Survey 2017–2020. Differences in social and political trust have been connected to per capita income and long-term economic growth (Knack and Keefer, 1997; Algan and Cahuc, 2013), short-term recessions (Searing, 2013), inequality (Algan and Cahuc, 2013), and ethnic fractionalization (Alesina et al., 1999; Alesina and La Ferrara, 2002; Miguel and Gugerty, 2005). Trust and corruption perceptions also correlate across countries (La Porta et al., 1997), although the relationship is complex and has been posited as both cause and effect (Morris and Klesner, 2010; You, 2018). Furthermore, simultaneous equation models indicate a feedback mechanism between social trust, corruption, and income inequality (Uslaner, 2018). While these factors help explain low levels of social and political trust in Latin America, other particularities come into play and help contextualize how trust may influence compliance with COVID-19 shelter-in-place orders and related mobility restrictions. Latin America is a region of mostly middle-income countries seeking to consolidate its democratic institutions amid high degrees of historic ethnic fractionalization, while registering among the highest rates of inequality and perceived corruption in the world. Political trust in the region therefore may not operate in the same way as in high-income countries with more consolidated democracies (Bargsted et al., 2017). Globally, high-income countries, where average education levels are higher, have more absolute levels of political trust. However, within-country differences between political trust and wealth, especially in Latin America, do not follow similar patterns between countries. In fact, Latin America registers more within-country than between-country differences in political trust (Bargsted et al., 2017). Fig. 2 depicts the relationship between region-level political trust and two socioeconomic proxies in Latin America grouped by the country's human development index (HDI) category (very high, high, and medium). Although overall trust levels do not differ between the three HDI categories in our sample, regions within “very high” HDI countries exhibit a positive correlation between political trust and education or wealth, similar to Europe, while there is negative correlation within “high” and “medium” HDI countries.4 Fig. 2 Socioeconomic Proxies and Political Trust in Latin America by Country HDI. Note: Very High HDI: Argentina, Chile, and Uruguay. High HDI: Bolivia, Brazil, Colombia, Dominican Republic, Ecuador, Jamaica, Mexico, Paraguay, Peru. Medium HDI: El Salvador, Guatemala, and Honduras. Years of education are the average number of years of schooling for respondents in each region within the respective countries. Wealth index is the percentage of the people in each country region above the national median wealth index, based on LAPOP. Fig 2 Several factors may explain the negative within-country correlation among LMICs in Latin America. Education can enhance political sophistication or the ability to discern and judge differences in corruption between institutions (Weitz-Shapiro and Winters, 2017). In this sense, Hakhverdian and Mayne (2012) find that education has both a conditional and conditioning effect on political trust (i.e., institutional trust and trust in political actors) and the relationship depends on the level of corruption in a society. In “corrupt societies” (e.g., Latin America), education is negatively related to political trust, while in “clean societies” (e.g., Europe) it is positively related. Furthermore, the negative effect of corruption on trust increases with more education. Thus, while some studies have found that country-level perception of corruption in Latin America does not decrease country-level rates of trust (Catterberg and Moreno, 2006; Bargsted et al., 2017), its effects are better seen when examining within-country differences. The negative correlation between education (and by proxy wealth) and trust in Latin America may also relate to the region's “inclusionary turn.” Historically, Latin America has been characterized by extreme inequality and social exclusion. Social policies exhibited large gaps in coverage, failing to give rural, informal, and unemployed workers access to social protection. However, recent decades under democratic rule have fostered an unprecedented expansion of inclusionary reforms and policies in Latin America, engendering an “inclusionary turn” (Kapiszewski et al., 2021). In the early 2000s, social programs were extended in several policy areas, including health care, pensions, and income support (Huber and Stephens, 2012; Pribble, 2013; Garay, 2016), with Latin American governments becoming global pioneers in the design and implementation of conditional cash transfer (CCTs) programs (Sugiyama, 2011; De la O, 2015). These targeted programs not only helped to increase household consumption and reduce poverty in the region (Fiszbein and Schady, 2009; Stampini and Tornarolli, 2012), but also linked poor and excluded citizens with government institutions in a sustained way, allowing for the potential establishment of trust relations. Evidence of the moderating influence of country type has been found in Europe, where the relationship between political trust and welfare spending resembles that of “twin peaks,” highlighting two mechanisms driving welfare spending in high- versus low-trust countries (Algan et al., 2016). In low-trust countries, welfare spending is large because “uncivic” people expect to free ride or benefit without assuming their share of the cost. In high-trust countries, “civic” people support high taxes and benefit expansion when they are surrounded by other high-trust citizens. Similar mechanisms may be at work in Latin America - a region with high levels of inequality, different reach of social protection programs, and weaker state capacity, all of which encourage middle- and high-income households to opt out of government services. Fig. 3 highlights the relationship between government social expenditure and political trust by education terciles in Latin America from 2004 to 2018, grouped by country HDI category. Until 2015, a positive correlation existed between increased government social spending and political trust. Yet the country HDI groups diverge thereafter, with medium HDI countries experiencing reduced spending and trust, high HDI countries maintaining spending and trust levels, and very high HDI countries exhibiting an inverse relationship. Notably, very high HDI countries overall have higher rates of government social spending, largely because of more robust social protection systems that incorporate, akin to those in Europe, larger proportions of the population than in medium and high HDI countries.Fig. 3 Social Expenditure and Political Trust by Education Levels. Note: Own elaboration based on LAPOP survey. Country social expenditure data come from United Nations Economic Commission for Latin America and the Caribbean (ECLAC) and the United Nations Development Programme's Human Development Index. Fig 3 The different configuration of trust in Latin America, how it operates, and for whom, raises the empirical question of how political trust may affect compliance differently in Latin America compared to Europe during the COVID-19 pandemic. 3 Data This study employs a difference-in-differences (DD) design, similar to that used by Bargain and Aminjonov (2020a) in the European COVID-19 context. Four data sources were used. The annual Latin America Public Opinion Project (LAPOP) survey included trust, demographic, and socioe-economic variables for 23,299 individuals in 282 regions across 15 countries in Latin America and Caribbean (LAPOP, 2019). Daily COVID-19 mortality figures were sourced from Our World in Data (Ritchie and Ortiz-Ospina, 2021). Lockdown stringency data came from the Oxford Covid-19 Government Response Tracker (OxCGRT) (Hale et al., 2022). Google mobility data provided region-level mobility (Google LLC, 2021). 3.1 Dependent variable: mobility As in previous studies (Bargain and Aminjonov, 2020a; Barrios et al., 2020), we use Google COVID-19 mobility data which provide indicators for countries and regions worldwide. Mobility fields include (i) residence, (ii) workplaces, (iii) grocery and pharmacy, (iv) retail and recreation, (v) parks (public gardens, dog parks, beaches, etc.), and (vi) transit stations (public transport hubs such as subway, bus, train stations, etc.). Residence captures the percentage of time spent in the home (lower values equal more mobility), while the latter five categories measure mobility to designated places outside the home (higher values equal more mobility). The mobility types outside the home could be further categorized as labor (workplace), primary consumption (grocery and pharmacy), secondary consumption (retail and recreation, parks), and transportation (transit stations). The smallest geographic unit available is regions within the country. Google calculated mobility using pre-COVID-19 levels in January and February 2020. In some cases, mobility data were not available for all regions or certain days. In these situations, we only included regions with 15 percent or less missing values or one day per week on average. Table 8.2.1 in the Suplementary Materials details the number of regions per mobility type and missing value threshold. The last column calculates the percentage of days without missing values for regions meeting the minimum 15 percent missing value threshold. Total missing values by days range between 1.2 percent (workplaces) to 4.2 percent (transit stations).5 We report results using residence and workplace mobility because they represent the upper and lower bound of the total number of regions and are the two mobility types with the least number of missing values. Furthermore, given realities in Latin America, parks and transit stations were not considered as suitable mobility measures, while retail and recreation confounded distinct activities. Meanwhile, grocery and pharmacies (primary consumption) mirror the results for residence (home) and workplaces (labor).6 Fig. 4 depicts the level of mobility patterns for residence and workplaces beginning on February 15. In mid-March, time in residence increases considerably while workplace mobility plummets.Fig. 4 Mobility trends in Latin America. Note: Own elaboration based on Google Mobility Data. Fig 4 3.2 Explanatory variables: trust, wealth, and stringency Political Trust. Following established measures of political trust (Zmerli and Newton, 2017), we used three questions from the LAPOP survey to measure the construct. The survey asked to what extent (1–7, “not at all” to “a lot”) the respondent trusted political parties, the president, and parliament. Responses were added and standardized. Following BA, we aggregated the variable at the regional level by calculating the share of respondents in the region above or below the mean.7 We also conducted a series of robustness checks testing different constructions of the trust variable.8 Wealth Index. A principal component analysis (PCA) was used to construct a wealth or poverty index variable (McKenzie, 2005; Vyass and Kumaranayake, 2006), a method commonly used for the LAPOP survey. The following household items reported in the LAPOP survey were included: television, refrigerator, traditional telephone, cellphone, vehicle, washing machine, microwave oven, indoor plumbing, indoor bathroom, and computer (Cordova, 2009). The first component generates a variable that gives more weight to assets that vary across households, so that the most common assets have zero weight (McKenzie, 2005). Since wealth has relative features and distribution is not uniform throughout Latin America, we followed the same method used for aggregating the trust variable at the regional level and calculated relative wealth for each region as the percentage of people above or below the median wealth for each country. The median was used because of the wealth measure's non-normal distribution (see Supplemental Materials for details). Policy Stringency. Policy stringency refers to the mobility restriction level mandated by national governments in response to the COVID-19 pandemic, as measured by the Oxford COVID-19 Government Response Tracker (OxCGRT) (Hale et al., 2022). A series of indicators were measured and rescaled to generate a score between 0 and 100, with 100 representing the highest degree of stringency. The composite index used is the daily average value. In Latin America, stringency jumped in mid-March after the World Health Organization (WHO) declared the pandemic, effectively initiating lockdown. Fig. 5 reports country-specific stringency trends across time for countries included from the LAPOP survey.9 Fig. 5 Stringency Trends in Latin America. Fig 5Source: Own elaboration based on Stringency data from OxCGRT. In Latin America, the lockdowns occurred even more abruptly than in Europe and were among the strictest and most protracted in the world early in the pandemic. All countries in the sample implemented severe restrictions around mid-March, irrespective of their levels of trust, wealth, and the number of COVID cases. Once these restrictions were implemented, the countries did not relax them until July, except for Uruguay. This finding suggests that pre-existing country wealth, trust, and COVID prevalence did not affect the probability of implementing mobility restrictions and that the mobility restrictions may be considered as exogenous. We examined effects until the lockdowns were eased and mobility returned in the region, selecting August 2020 as the cutoff. 3.3 Covariates COVID-19 Deaths. Daily reported deaths may serve as a public signal about the risk of non-compliance with shelter-in-place or social distancing orders. We obtained daily deaths from Our World in Data (Ritchie and Ortiz-Ospina, 2021). Following BA, we include this covariate in our model, using the country-level measure. We did not expect particularized trust to be predictive of mobility, which the results confirmed. Finally, we replicated the model with a political trust variable generated from the Latinobarometer survey, which included 14 countries for LAPOP, except Jamaica. Since the latter survey did not enable the creation of a robust wealth index, the estimations were made both with and without years of education as a wealth proxy. Regardless, we found consistent results and replicated the signs and significance of results for political trust. Population Density. Population density is known to affect virus spread because of the likelihood of less physical distancing, with urban environments at higher risk of contagion. Like BA, we control for this factor by calculating regional population density. Since population figures are relatively stable, we constructed the variable based on the most recent estimates from each country's statistical department. To ease interpretation, we converted values to population density per 10,000 inhabitants. Age. Age could affect mobility in at least two ways. First, the older the person is, the less economically active they may be. Second, the older the population, the more susceptible they are to complications and mortality from the virus, leading them to take more precautions. To control for these possible effects, we constructed a region age variable by following the same procedure as for trust and wealth and calculated the proportion of people in each region above the country median age, given the variable's non-normal distribution. Mask Mandates. Although early in the pandemic there was some uncertainty regarding the effectiveness of masks, many countries implemented mask mandates. As the weeks and months passed, however, mask use became more common. Regardless, the existence of mandates may affect the citizen's risk aversion towards the virus and mobility. We therefore included a dummy control variable for mask mandates, capturing whether mask use was obligatory either in all public spaces or simply to leave the home. Formality. The unemployment rate in high-income countries may reflect the health of the economy and other labor-related conditions and was thus used in the BA model. However, in LMICs where welfare schemes are historically weaker, the unemployment rate may not proxy economic health given the role of the informal sector, especially in Latin America, in absorbing the un- and under-employed. Using unemployment rates in Latin America is also problematic because of different methods of calculation in each country and region. Regardless, for comparison with the BA model we sought to include a labor formality measure. The LAPOP survey asks if the respondent or respondent's employer makes pension contributions for retirement. This question has been demonstrated as a strong proxy for formality (LAPOP, 2019). The aggregate region-level variable represents the percentage of people in each region who work in the formal sector. 4 Graphical evidence and empirical approach We initially examine the graphical evidence to establish the existence of parallel trends prior to the lockdowns and then specify the DD models used to confirm the observed relationship. Fig. 6a and b depict the parallel trends in mobility from one month before country lockdowns (February 15, 2020) to five months after (August 5, 2020). For ease of interpretation, high and low political trust and wealth were calculated using the variable mean as a cutoff. Across the four major mobility types, we see parallel trends until the first half of March, when trajectories diverge. On March 11, the World Health Organization's made an official declaration of the global pandemic. Immediately after this announcement, governments in Latin America swiftly imposed quarantines, as seen in Fig. 5. In our sample, the median OxCGRT stringency index was 30 on March 13, 50 on March 16, and 70 on March 19. All countries in our sample surpassed 50 between March 3 and March 19. We use March 16 as the regional lockdown rate because it was the day the country-level median in our sample reached 50. Regardless, results are robust to different lockdown dates between March 13 and March 19 (see Supplemental Material).Fig. 6 Note: Local polynomial fit of the daily variation across regions of Latin America and the Caribbean and with 95 percent confidence intervals (CI). Fig 6 Following the BA model, our DD estimation exploits the panel nature of the data and tests for the impact of political trust on mobility over time using the following specification:(1) Mobilityit=αT+βTTrusti+γTPostTrusti+δTDeathit−1+ηTXi+λTPostXi+ζtT+πCT+εit The treatment variable is the level of political trust for region i, constructed as previously detailed. Post is the treatment period. For direct comparison with BA, our initial estimation is for March 1 to April 5. To examine longer-term effects, we extended the treatment period to June 5 and August 5, respectively. γT denotes the double-difference estimator of interest, while αT is the constant selection bias between regions. We control for day dummies ζT and country dummies πT . To make our model comparable to BA, we include additional region-level controls represented by vector Xi, including population density, the number of deaths reported the previous day T, and a region-level formality indicator, as discussed in the previous section. However, to further strengthen the model we include two additional covariates not used by BA. In the months after the onset of the pandemic, it became apparent that mortality risk was greater the older the population and that masks could mitigate virus spread.10 The model was run with and without weighting for region and standard errors were cluster-bootstrapped at the region level since the panel data of daily mobility includes multiple region-level observations. A further specification included region effects in the model, creating the following equation:(2) Mobilityit=αT+γTPostTrusti+δTDeathit−1+λTPostXi+ζtT+πiT+εit The region effect is captured in dummies πT, which absorb the pre-lockdown time invariant characteristics of population density, COVID-19 deaths the previous day, formality, age, and mask. Once again versions of the model were run with and without region weighting. Subsequently, we rerun both estimations replacing formality with wealth:(3) Mobilityit=αT+βTTrusti+γTPostTrusti+σTWealthi+θTPostWealthi+δTDeathit−1+ηTXi+λTPostXi+ζtT+πCT+εit (4) Mobilityit=αT+γTPostTrusti+θTPostWealthi+δTDeathit−1+λTPostXi+ζtT+πCT+εit As with the original model, country and region effect models were examined for each period, with and without region reweighting and cluster-bootstrapped standard errors at the regional level. Given consistency of the results, we report the region fixed effects model without region reweighting. 5 Results 5.1 Political trust and mobility Table 1 shares results for the effects of political trust on residential and workplace mobility over time in 2020 - March to April, March to June, and March to August. Results for columns A, D, and G offer a direct comparison with the BA results for Europe, while columns B, E, and H include age, and columns C, F, and I incorporate both age and mask mandates.Table 1 Residence & workplaces - political trust. Table 1 Continuous trust panel DD (using daily regional mobility) 01 march - 05 april 01 march - 05 june 01 march - 05 august (A) (B) (C) (D) (E) (F) (G) (H) (I) Residence Post x Political Trust −14.171* −14.531* −13.982* −10.330* −10.512* −10.301 −9.182* −9.397 −8.759 (4.685) (4.626) (4.718) (3.949) (3.925) (3.991) (3.606) (3.599) (3.634) Controls X: # daily deaths (t-1) −0.111* −0.110* −0.117* 0.004* 0.004* 0.004* 0.008* 0.008* 0.007* (0.018) (0.018) (0.017) (0.001) (0.001) (0.001) (0.001) (0.001) (0.002) Population density 6.676* 6.473* 6.415* 7.361* 7.262* 7.341* 6.353* 6.235* 6.506*** (1.992) (2.031) (1.994) (1.790) (1.802) (1.824) (1.811) (1.835) (1.911) Age 14.271 12.702 7.001 6.757 8.394 7.569 (11.362) (11.261) (8.594) (8.652) (7.215) (7.366) Mask mandate 1.926* −0.477 −1.632 (0.984) (0.967) (1.002) Formality −5.811 −5.953 −3.397 −10.331* −10.403* −10.634* −8.714* −8.796* −9.616* (2.662) (2.668) (2.938) (2.067) (2.063) (2.191) (1.860) (1.861) (1.951) Observations 6336 6336 6336 17,072 17,072 17,072 27,808 27,808 27,808 R-squared 0.885 0.886 0.889 0.878 0.878 0.878 0.836 0.837 0.837 Workplaces Post x Political Trust 15.961 18.364 11.822 15.732 13.291 14.494 12.371 13.431 13.941 (7.420) (7.557) (7.185) (5.939) (6.088) (6.013) (5.646) (5.777) (5.712) Controls X: # daily deaths (t-1) 0.003 0.002 0.035 −0.008* −0.008* −0.009* −0.014* −0.014* −0.014* (0.033) (0.032) (0.036) (0.003) (0.003) (0.003) (0.003) (0.003) (0.003) Population density −14.982* −14.232* −13.693* −17.001* −16.554* −16.082* −16.001* −15.671* −15.502* (4.281) (4.456) (4.270) (3.302) (3.336) (3.199) (3.596) (3.640) (3.560) Age −35.971 −34.842 −22.020* −22.491 −15.862 −15.912 (15.251) (14.433) (11.251) (11.091) (9.909) (9.846) Mask mandate −7.006* −1.208 −0.372 (1.599) (1.529) (1.645) Formality 7.907 8.511 −0.639 11.431* 11.812* 12.001* 12.092* 12.364* 12.533* (3.508) (3.535) (3.849) (2.697) (2.710) (2.705) (2.581) (2.597) (2.596) Observations 10,145 10,145 10,145 27,346 27,346 27,346 44,544 44,544 44,544 R-squared 0.884 0.885 0.891 0.853 0.853 0.854 0.806 0.806 0.806 Note: Difference-in-differences (DD) estimation of Google mobility index (for different types of activity as indicated) or index of time spent in private residence on trust data (LAPOP) using daily regional variation for the period from March 1 to April 5, June 5, and August 5, respectively, with continuous trust (regional trust measure, calculated as the proportion of people with trust scores above national average). We report the coefficient on Post x Trust, with Post a dummy indicating the average lockdown date (March 16, 2020). Estimations include the lagged daily number of COVID-19 fatalities, day dummies, region fixed effects and Post interacted with regional control variables. Robust standard errors in parentheses, cluster-bootstrapped at region level (1000 replications). Significance level: * p < 0.01, p < 0.05, p < 0.1. Across all model versions and time periods, as the proportion of people in the region with political trust above the national average moves from 0 to 1, mobility increases on the 100-point mobility scale between 8.8 and 14.5 for residence (negative coefficients mean less time spent in the residence) and 11.8 and 18.4 for workplace mobility. While the magnitudes and significance were consistent for workplaces across the three periods, the magnitudes for residential mobility faded, though significance remained. These signs and magnitudes are the reverse of that found by BA in Europe. While more political trust decreases mobility in Europe, it increases mobility in Latin America. During Europe's initial lockdown period, an increase in the deaths reported the day before predicted less mobility. In Latin America, the relationship was more complex. In the first two weeks after lockdowns, daily deaths predicted more time spent outside that home, but by the second and third periods daily deaths became predictive of less mobility with increasing magnitudes. As for workplace mobility, in the first period deaths were not predictive but became so with increasing magnitudes in the second and third periods. These results suggest that information on deaths may have initially been a noisy signal which did not take effect until reporting systems improved and the population learned the full risks of the virus. As in Europe, population density consistently relates to less mobility across all time periods in Latin America. These effects are roughly twice as large for workplace mobility compared to residence. Although the effect of age on residential mobility was not significant at any point, it had a significant negative effect on workplace mobility in the first period, after which magnitudes waned, with significance disappearing by the third period. While we expected mask mandates to relate to increased mobility, they initially predicted less mobility for both residential and workplace mobility after the first two weeks before fading thereafter. Two interpretations are possible. First, the existence of mandates may have sent a signal of the seriousness of the virus in the first two weeks after the lockdown. Second, increased country adoption of mask mandates after the initial period may have muted detection of effects in this analysis. Finally, although the BA model did not reveal clear patterns for the impact of unemployment in Europe, regions in Latin America with higher formality rates were related to increased mobility. 5.2 Wealth, political trust, and mobility Table 2 shares results for the effects of political trust and wealth on residential and workplace mobility from March to April, March to June, and March to August 2020.Table 2 Residence & workplaces - political trust and wealth. Table 2 Continuous trust panel DD (using daily regional mobility) 01 march - 05 april 01 march - 05 june 01 march - 05 august (A) (B) (C) (D) (E) (F) (G) (H) (I) Residence Post x Political Trust −11.961* −12.241 −11.882 −8.595 −8.719 −8.948 −7.853 −8.005 −7.879 (4.992) (4.974) (4.919) (4.277) (4.284) (4.242) (3.863) (3.888) (3.893) Post x Wealth index 7.271 7.574 7.400 6.284 6.417 6.606 4.907* 5.069* 5.011* (3.613) (3.513) (3.489) (2.950) (3.000) (2.957) (2.648) (2.590) (2.606) Controls X: # daily deaths (t-1) −0.126* −0.125* −0.129* 0.000 0.001 0.002 0.005* 0.005* 0.005* (0.018) (0.018) (0.017) (0.002) (0.001) (0.002) (0.001) (0.001) (0.002) Population density 4.726 4.441 4.527 5.299* 5.174* 4.945* 4.703* 4.552* 4.566* (1.928) (1.941) (1.917) (1.510) (1.508) (1.491) (1.520) (1.536) (1.553) Age 14.821 13.942 6.517 7.390 7.921 7.920 (11.121) (10.801) (9.269) (8.995) (7.961) (7.897) Mask mandate 2.884* 1.419 −0.036 (0.927) (1.049) (1.072) Observations 6336 6336 6336 17,072 17,072 17,072 27,808 27,808 27,808 R-squared 0.885 0.886 0.890 0.874 0.874 0.875 0.834 0.834 0.834 Workplaces Post x Political Trust 12.623* 14.751* 12.692* 8.176 9.442 11.012* 9.225 10.094* 11.023* (7.574) (7.634) (7.092) (5.988) (6.066) (5.854) (5.727) (5.800) (5.646) Post x Wealth index −10.892 −11.801 −12.372 −11.641* −12.183* −12.424* −9.687* −10.060* −10.231* (5.159) (5.101) (4.830) (3.766) (3.749) (3.684) (3.568) (3.568) (3.530) Controls X: # daily deaths (t-1) 0.035 0.037 0.041 −0.003 −0.003 −0.005 −0.008* −0.008* −0.010* (0.032) (0.033) (0.032) (0.003) (0.003) (0.003) (0.003) (0.003) (0.003) Population density −11.444* −10.392 −10.572 −12.911* −12.303* −11.454* −12.332* −11.910* −11.382* (4.308) (4.497) (4.441) (2.819) (2.873) (2.740) (3.109) (3.171) (3.087) Age −36.193 −37.643*** −21.363* −22.764 −14.622 −15.591 (15.102) (14.091) (11.522) (11.153) (10.522) (10.283) Mask mandate −7.078* −2.824* −1.863 (1.351) (1.492) (1.608) Observations 10,145 10,145 10,145 27,346 27,346 27,346 44,544 44,544 44,544 R-squared 0.884 0.885 0.892 0.853 0.853 0.853 0.806 0.806 0.806 Note: Difference-in-differences (DD) estimation of Google mobility index (for different types of activity as indicated) or index of time spent in private residence on trust data (LAPOP) using daily regional variation for the period from March 1 to April 5, June 5, and August 5, respectively, with continuous trust (regional trust measure, calculated as the proportion of people with trust scores above national average). We report the coefficient on Post x Trust and Post x Wealth, with Post a dummy indicating the average lockdown date (March 16, 2020). Estimations include the lagged daily number of COVID-19 fatalities, day dummies, region fixed effects and Post interacted with regional control variables. Robust standard errors in parentheses, cluster-bootstrapped at region level (1000 replications). Significance level: * p < 0.01, p < 0.05, p < 0.1. During the first two weeks after the lockdown, as the proportion of people in the region with political trust above the national average moves from 0 to 1, mobility increases on the 100-point mobility scale between 7.9 and 12.2 for residence (negative coefficient means less time spent in home) and between 8.2 and 14.8 for workplace mobility. Despite similar magnitudes, there is greater significance for residence, while workplace mobility is marginally significant. Wealth predicts decreased mobility across all time periods. However, for residential mobility the significance and magnitudes fade, while for workplace mobility the effect sizes are larger, remain consistent across time periods, and maintain marginal significance throughout. Results for deaths, population density, age, and mask mandates replicate those found in the previous model. Table 3 shares results for all mobility types for the three time periods using the political trust and wealth region fixed effects model (columns C, F, and I in Table 2, since this estimation was robust to other specifications,see Supplementary Material.). On one hand, political trust results for grocery and pharmacy, which we consider as primary consumption, are consistent with residential and workplaces (labor) mobility, though wealth is not predictive. On the other hand, political trust is not predictive of retail and recreation, which we consider a confounded measure of secondary consumption (alongside parks), while wealth is predictive.Table 3 Effect of trust and wealth on alternative mobility types. Table 3Panel difference in difference estimates of Post Trust Residence Workplaces Grocery and pharmacy Retail and recreation Parks Transit stations (i) (ii) (iii) (iv) (v) (vi) 01 march - 05 april Political trust −11.881* 12.691* 19.411* 4.315 1.044 12.222 (4.919) (7.092) (10.821) (8.643) (7.621) (10.351) Wealth index 7.400 −12.372 −3.834 −11.763** −9.348* −9.723 (3.489) (4.830) (7.856) (5.648) (5.323) (6.694) Observations 6336 10,145 8351 8964 9540 7488 R-Squared 0.890 0.892 0.827 0.911 0.884 0.906 01 march - 05 june Political trust −8.948** 11.012* 23.282 1.579 −4.220 2.554 (4.242) (5.854) (10.232) (7.537) (7.217) (8.105) Wealth index 6.606 −12.421* −4.408 −10.131 −6.908 −7.242 (0.002) (3.684) (7.425) (4.650) (4.983) (5.104) Observations 17,072 27,346 22,503 24,153 25,705 20,176 R-Squared 0.875 0.853 0.786 0.877 0.854 0.896 01 march - 05 august Political trust −7.879** 11.023* 22.723** 2.172 −4.936 2.425 (3.893) (5.646) (9.959) (7.728) (7.264) (8.113) Wealth index 5.011* −10.232* −4.882 −9.798 −5.240 −6.411 (2.606) (3.530) (7.177) (4.817) (4.939) (5.098) Observations 27,808 44,544 36,655 39,342 41,870 32,864 R-Squared 0.834 0.806 0.752 0.833 0.805 0.861 Note: Difference-in-differences (DD) estimation of Google mobility index (for different types of activity as indicated) or index of time spent in private residence on trust data (LAPOP) using daily regional variation for the period from March 1 to April 5 and August 5, respectively, with continuous trust (regional trust measure, calculated as the proportion of people with trust scores above national average). We report the coefficient on Post x Trust and Post x Wealth, with Post a dummy indicating the average lockdown date (March 16, 2020). Estimations include the lagged daily number of COVID-19 fatalities, day dummies, region fixed effects, and Post interacted with regional control variables. Robust standard errors in parentheses, cluster-bootstrapped at region level (1000 replications). Significance level: * p < 0.01, p < 0.05, p < 0.1. In sum, wealth more consistently predicts increased compliance across time, as observed in both developed (Wright et al., 2020) and developing (Bargain and Aminjonov, 2020b) countries. Furthermore, these effects are sustained over several months in Latin America. However, even when controlling for weatlh, the effects of political trust on decreased compliance contradicts findings from high-income countries (Bargain and Aminjonov, 2020a; Barrios et al., 2020; Durante et al., 2021). We seek to explain these results by focusing on experiences with social protection and corruption and their relation to political trust. 6 Mechanisms While most studies of political trust and compliance, conducted largely in high-income countries, indicate that trust increases compliance, some evidence suggests otherwise. An early study in Singapore posited that the high levels of political trust may have created a moral hazard whereby citizens were more risk tolerant given faith in government management of the crisis (Wong and Jensen, 2020). High political trust has also been linked to less protective actions in the face of natural disasters (Wachinger et al., 2012). Other research has examined the evolving relationship between trust, risk perception, and compliance during the COVID-19 pandemic. A series of cross-sectional surveys in the United Kingdom find that trust in government was a consistent predictor of decreased perception of COVID-19 risk, while the heterogeneous effect of risk perception on protective health behaviors increased over time (Schneider et al., 2021). Thus, even in high-income countries, the dynamic relationship between political trust and compliance is not straightforward. In comparison, experiments administered to cross-sectional waves in Wuhan before and at the onset of the COVID-19 crisis revealed decreased trust, increased risk aversion, and greater sensitivity to risk effects in gain and loss domains (i.e., a linearization of the Prospect Theory value function) immediately after the lockdown, with transitory effects following the death of a famed whistleblower (Shachat et al., 2021). In line with prior studies of natural disasters, recessions, and wars as well as increasing evidence from the pandemic, our main results highlight how the relation between trust and risk are contingent on context. The counterintuitive relationship between political trust and compliance in Latin America during the pandemic suggests either that political trust creates a moral hazard or political trust proxies other variables or underlying mechanisms that may affect compliance decisions in the region. We explore these possibilities by decomposing underlying predictors of political trust and wealth and testing the effects of predictors on compliance. 6.1 Decomposing political trust and wealth We initially identified via a stepwise regression predictors of political trust and wealth, respectively. For the political trust stepwise model, we systematically introduced socio-demographic variables, including density, formality, wealth, and education. Next, we included measures of experiences with social protection, corruption, and crime, all of which are related in the literature to public goods provision (or lack thereof). The final regressions added interpersonal trust and associativity as controls.11 For the stepwise regression with wealth as the dependent variable, we followed the same sequence with the independent variables, except we included political trust as a predictor. Since our main results were conducted at the regional level, all variables were aggregated at this level. Formality, wealth, and density were constructed as in the main results estimation. Education captured the number of years of schooling. Assistance was the response to whether the person or someone in the household had received any regular or periodic government benefits in the form of money, food, or products, not counting pensions. Corruption measured whether in the last 12 months a police officer had asked the respondent for a bribe. Security captures the level of safety people perceive in their neighborhood because of experience as the victim of an assault or robbery. To calculate associativity, we used the frequency of religious, school, and community association activity. Interpersonal trust was the degree of trust in people in the local community. Scores were standardized. Results from Table 8.4.1 (see Supplemental Material) finds that the most important predictors of political trust are government assistance (positive) and police bribes (negative). Table 8.4.2 (see Supplemental Material) identifies the same two predictors as the most important for wealth, except with reverse signs. Unsurprisingly, density and education were also predictive. Government assistance was only marginally predictive of wealth, once controlling for the other variables.12 Given that the DD model used for the main results controlled for density and wealth, one may hypothesize that the predictive relationship between political trust and mobility could be driven by having either benefited from government assistance or suffered from police corruption. Next, we removed political trust and wealth from the DD model and replaced them with the three variables predictive of both - social protection, police bribes, and education.13 6.2 Social protection, corruption, and education The main results indicated that political trust predicted more mobility (less compliance) immediately after lockdown, while wealth predicted less mobility (more compliance) in all time periods. The results for wealth suggest that people with greater economic necessity and less ability to smooth consumption may be more compelled to leave the home to work (Ravallion, 2020; Robalino, 2020) or engage in occupations they cannot perform in the home (Dingel and Neiman, 2020; Garrote et al., 2020). However, contrary to high-income countries, results for political trust indicate that it does not increase compliance (Bargain and Aminjonov, 2020a; Brodeur et al., 2020; Brzezinski et al., 2020), leaving two options. Either political trust creates a moral hazard (Wong and Jensen, 2020) or it proxies for different mechanisms underlying compliance in Latin America - or both. Government assistance, which is highly correlated with political trust, may increase the risk tolerance of populations. For example, in the two weeks after the lockdowns, all 15 countries in the sample announced emergency social protection mechanisms, yet logistically had not begun mass distribution. These announcements may have generated a short-term public health moral hazard for those who had benefited previously from the government's social protection schemes, regardless of wealth or education. As for corruption experiences, which also relate to less political trust, experiences with bribes may lead people to disregard government mandates or, because of inconsistent application of the orders, may encourage them to comply more because of the risk of bribes for non-compliance if caught breaking mobility restrictions. Table 4 reports results for social protection, police bribes, and education on a monthly basis between April and August 2020. For the first two weeks of the lockdown, as the proportion of the regional population benefiting previously from social protection moves from 0 to 1, time spent in the home decreases by 16.3, while workplace mobility increases 21.2 on the 0 to 100 scale. In subsequent months, the magnitudes and significance of the effects waned. Meanwhile, police bribes related to a 13.3 decrease in time spent in home and 33.6 increase in workplace mobility in the first two weeks after the lockdowns, though this effect disappears by early May. Interestingly, for bribes the magnitudes of the effects increase in subsequent months, reaching marginal significance. Finally, education as a wealth proxy predicts decreased mobility consistently across all time periods. These results replicate in part the main findings, while offering more insight on what may drive the short-term, dynamic results of political trust.Table 4 Education, social protection, and corruption. Table 4 Panel DD (using daily regional mobility) 01 march - 05 april 01 march - 05 may 01 march - 05 jun 01 march - 05 jul 01 march - 05 aug Residential Post x Assistance −16.301 −10.622* −7.160* −5.370 −4.081 (4.226) (3.822) (3.791) (3.603) (3.444) Post x Police bribe −13.271 2.961 6.629 5.182 4.332 (5.660) (4.930) (4.776) (4.515) (4.248) Post x Education 1.788* 1.684* 1.708* 1.721* 1.625* (0.329) (0.298) (0.295) (0.287) (0.276) Controls X: # daily deaths (t-1) −0.126* −0.011* 0.000 0.003 0.003 (0.018) (0.002) (0.001) (0.001) (0.001) Population density 4.290 4.246* 4.060* 3.749* 3.541* (1.690) (1.526) (1.383) (1.357) (1.352) Age 12.861 12.093 11.052 11.694 11.411 (10.122) (8.649) (8.240) (7.792) (7.208) Mask mandate 5.538* 3.143*** 1.882* 0.944 0.414 (1.121) (1.043) (1.049) (1.031) (1.016) Observations 6336 11,616 17,072 22,352 27,808 R-squared 0.905 0.903 0.881 0.857 0.839 Workplaces Post x Assistance 21.221* 8.343 7.070 7.216 5.732 (5.878) (5.344) (5.317) (5.170) (4.964) Post x Police bribe 33.622* −4.987 −14.252* −14.040* −15.291* (9.353) (8.619) (8.609) (8.489) (8.232) Post x Education −2.370* −2.056* −1.547* −1.278* −0.956*** (0.319) (0.334) (0.321) (0.325) (0.327) Controls X: # daily deaths (t-1) 0.058* 0.004 −0.002 −0.009* −0.009* (0.034) (0.004) (0.003) (0.003) (0.003) Population density −11.541* −11.162* −11.961* −12.351* −12.443* (3.539) (2.893) (2.710) (2.935) (3.002) Age −35.061* −32.092* −23.852 −19.661* −15.764 (13.122) (11.331) (10.422) (10.143) (9.765) Mask mandate −10.261*** −2.254* −1.967 −1.381 −0.975 (1.531) (1.337) (1.500) (1.568) (1.623) Observations 10,145 18,605 27,346 35,802 44,544 R-squared 0.898 0.893 0.854 0.825 0.806 Note: Difference-in-differences (DD) estimation of Google mobility index (for different types of activity as indicated) or index of time spent in private residence on trust data (LAPOP) using daily regional variation for the period from March 1 to April 5, June 5, and August 5, respectively, with continuous trust (regional trust measure, calculated as the proportion of people with trust scores above national average). We report the coefficient on Post x Assistance, Post x Police bribe and Post x Education, with Post a dummy indicating the average lockdown date (March 16, 2020). Estimations include the lagged daily number of COVID-19 fatalities (cf. Our World in Data), day dummies, region fixed effects and Post interacted with regional control variables (population density). Robust standard errors in parentheses, cluster-bootstrapped at region level (1000 replications). Significance level: * p < 0.01, p < 0.05, *p < 0.1. We interpret these results as evidence for a public health moral hazard. Social protection is only predictive at the beginning of the lockdown. If the variable were to capture fully economic vulnerability with which it correlates, then one would expect it to remain predictive when the economic constraints were greater for staying at home. Instead, both education and wealth capture across time the consistent effects of the economic ability to adhere to mobility restrictions. One alternative explanation is that the emergency cash transfers activated by the region's governments may have encouraged mobility among poor households early in the lockdown; however, mass transfers were not distributed so quickly (Gentilini et al., 2020). A second alternative is that the transfers, as designed, encouraged less mobility. Yet this would likely have affected the impact of the wealth and education variables, whose magnitudes and significance remained consistent throughout. Furthermore, some evidence from impact evaluations of emergency transfers suggest that transfers may have increased mobility by increasing the economic activity of recipients (Bird et al., 2023; Brooks et al., 2022). Unfortunately, data limitations do not allow further testing of these hypotheses. 7 Conclusion At the beginning of the pandemic, the implementation of government measures was believed to require a level of citizen trust in government. Not much was known nor understood about the virus, how it spread, and the risks it created. Lower-income households in both developed and developing countries suffered from irregular cash flows and minimum savings. With lower-income employment concentrated in commerce and service sectors, more vulnerable citizens had less opportunities to work from home. People from these households simply could not afford to restrict mobility for extended periods, spurring the creation of emergency social protection (Gentilini et al., 2020). While evidence suggests that political trust and wealth explain increased compliance in high-income countries, the mechanisms remain unclear and less evidence exists for LMICs, where the relationship between wealth and trust are often reversed. Our results provide evidence for how trust operates differently in Latin America, and perhaps other LMICs, compared to high-income countries. Political trust does not act in the same way as envisioned for high-income settings and may even serve as a proxy in Latin America for other mechanisms. Unlike in Europe, lower-income segments in Latin America exhibit higher levels of political trust. While wealth predicts compliance in the region, as seen in high-income countries, political trust counterintuitively predicts more mobility, suggesting the possibility that political trust increases risk tolerance. By identifying social protection as a main driver for political trust in Latin America, we offer evidence for the existence of a public health moral hazard during the immediate lockdown period in the region. While further exploration is needed to trace the relationship between social protection and compliance during the pandemic, the results for political trust highlight the importance of understanding the distinct relationship between political trust and compliance in LMICs. This requires moving beyond between-country studies of trust and examining determinants of within-country trust based on government-citizen relationships. In other words, future studies of political trust and compliance should extend the empirical base beyond high-income countries because they likely lack external validity for LMICs, where the relationship between trust and compliance may differ because of distinct relationships across socioeconomic gradients with government services. With this knowledge, policymakers, especially in Latin America, could better craft social protection policies in the face of future public health or natural disaster emergencies. Supplementary material Supplementary material associated with this article can be found, in the online version, at 10.1016/j.jebo.2022.12.010. Appendix A Supplementary materials Supplementary Data S1 Supplementary Raw Research Data. This is open data under the CC BY license http://creativecommons.org/licenses/by/4.0/ Supplementary Data S1 Data availability Data will be made available on request. This research was supported by the Universidad del Pacıfico Vice-Rector Research Fund, awarded for the project ”COVID-19 and Institutional and Interpersonal Trust in Peru.” The authors declare that they have no conflict of interest in the preparation of this study. 1 In the United States, trust was further related to political ideology (Allcott et al., 2020; Barrios and Hochberg, 2021; Painter and Qiu (2021)) and a community's historical legacy as a frontier region (Bazzi et al., 2021). 2 Other studies suggest that cultural factors of individualism (vs. collectivism) and looseness (vs. tightness), which negatively correlate, also predict compliance with mobility restrictions both across and within countries (Chen et al., 2021; Gelfand et al., 2021). However, there may be an inherent contradiction in these findings in the United States. The U.S. South, the region with the least compliance, has both the highest relative degree of tightness and individualism in the country. 3 While an orthogonal line connecting low particularized and high generalized trust could be drawn, the empirical relationship is noisy. 4 Plots of political trust and education of countries using the World Values Survey indicate a similar global pattern for more versus less developed countries around the globe. See Supplemental Material. 5 In these cases, we impute the missing value by averaging the value for one day before and one day after. Our estimation results are consistent across missing value thresholds. See Supplemental Material. 6 For Europe, Bargain and Aminjonov (2020a) report retail and recreation for their main results. In general, our results are inversely consistent with this outcome. 7 Also like BA, we calculated alternative forms of constructing the regional trust variable, including using the country median and Latin American mean and median. Results were consistent. See Supplemental Material. 8 See Supplemental Material document for robustness checks, including the following. We calculated scores for institutional trust and interpersonal or particularized trust, understanding them as distinct constructs. Theoretically, we did not expect particularized trust to be predictive of mobility, which the results confirmed. Finally, we replicatedthe model with a political trust variable generated from the Latinobarometer survey, which included 14 countries forLAPOP, except Jamaica. Since the latter survey did not enable the creation of a robust wealth index, the estimationswere made both with and without years of education as a wealth proxy. Regardless, we found consistent results andreplicated the signs and significance of results for political trust. 9 Nicaragua was not included in the sample because the country never surpassed 20 on the policy stringency index, well below the level considered as a lockdown. 10 We thank an anonymous reviewer for this suggestion. 11 As seen in Table 8.4.1 in the Supplemental Material, these variables did not change results for the other predictors. 12 Civic mechanisms, whereby citizens feel a social duty to the community to comply, could act as a separate mechanism (Barrios et al., 2020; Durante et al., 2021), but the LAPOP survey did not capture this construct. 13 We also confirmed parallel trends for these variables prior to the pandemic. ==== Refs References Alesina A. La Ferrara E. Who trusts others? Journal of Public Economics 85 2 2002 207 234 10.1016/S0047-2727(01)00084-6 Alesina A. Baqir R. Easterly W. Public goods and ethnic divisions Quarterly Journal of Economics 114 4 1999 1243 1284.doi 10.1162/003355399556269 Algan, Y., Cahuc, P., 2013. Trust, growth, and well-being: new evidence and policy implications. In: Aghion, P. and Durlauf, S. (Eds.). Handbook of Economic Growth, 126. Amsterdam: Elsevier, pp. 49–120. doi:10.1016/B978-0-444-53538-2.00002-2. Algan Y. Cahuc P. Sangnier M. Trust and the welfare state: The twin peaks curve Economic Journal 126 2016 861 883 10.1111/ecoj.12278 Allcott H. Boxell L. Conway J. Gentzkow M. Thaler M. Yang D. Polarization and public health: Partisan differences in social distancing during the coronavirus pandemic Journal of Public Economics 191 104254 2020 10.1016/j.jpubeco.2020.104254 Aminjonov, U., Bargain, O., Bernard, T., 2021. Gimme shelter: Social distancing and income support in times of pandemic. IFPRI Discussion Paper 2042. Washington, DC: International Food Policy Research Institute (IFPRI). doi:10.2499/p15738coll2.134575. Bargain O. Aminjonov U. Trust and compliance to public health policies in times of COVID-19 J. Public Econ. 192 104316 2020 10.1016/j.jpubeco.2020.104316 Bargain, O., Aminjonov, U., 2020b. Between a rock and a hard place: poverty and COVID-91 in developing countries. IZA Discussion Paper Series 13297. Bargsted, M., Somma, M., Castillo, J., 2017. Political trust in Latin America. In: Zmerli, S., van Der Meer, T. (Eds.). Hanbook on Political Trust. Cheltenham: Edward Elgar, pp. 395-417. doi:10.4337/9781782545118.00036. Barrios J. Hochberg Y. Risk perceptions and politics: Evidence from the COVID-19 pandemic Journal of Financial Economics 142 2 2021 862 879 10.1016/j.jfineco.2021.05.039 34658487 Barrios J. Benmelech E. Hochberg Y. Sapienza P. Zingales L. Civic and social distancing during the COVID-19 pandemic Journal of Public Economics 193 104310 2021 10.1016/j. jpubeco.2020.104310 Bazzi S. Fiszbein M. Gebresilasse M. Rugged individualism” and collective (in)action during the COVID-19 pandemic Journal of Public Economics 195 104357 2021 10.1016/j.jpubeco.2020.104357 Bicchieri C. Fatas E. Aldama A. Casas A. Deshpande I. Lauro M. In science we (should) trust: Expectations and compliance across nine countries during the COVID-19 pandemic PLoS ONE 16 6 2021 e0252892 10.1371/journal.pone.0252892 Bird, M., Frisancho V., Lavado,P., 2023. The Effectiveness of Emergency Transfers During the Pandemic: Evidence from Poor Households in Peru. Inter-American Development Bank Working Paper, Washington, D.C. Blair R. Morse B. Tsai L. Public health and public trust: Survey evidence from the Ebola virus disease epidemic in Liberia Social Science & Medicine 172 2017 89 97 10.1016/j.socscimed.2016.11.016 27914936 Brodeur A. Clark A. Fleche S. Powdthavee N. COVID-19, lockdowns and well-being: Evidence from Google trends Journal of Public Economics. 2020 104346 10.1016/j.jpubeco.2020 33281237 Brooks W. Donovan K. Johnson T.R. Oluoch-Aridi J. Cash transfers as a response to COVID-19: experimental evidence from Kenya Journal of Development Economics 158 2022 102929 10.1016/j.jdeveco.2022.102929 35784379 Brzezinski A. Deiana G. Kecht V. Van Dijcke D. The COVID-19 Pandemic: Government vs. Community Action Across the United States. INET Oxford Working Papers 2020-06, Institute for New Economic Thinking at the Oxford Martin School 2020 University of Oxford Catterberg A. Moreno A. The individual bases of political trust: Trends in new and established democracies International Journal of Public Opinion Research 18 1 2006 31 48 10.1093/ijpor/edh081 Chen Ch. Frey C. Presidente G. Culture and contagion: individualism and compliance with COVID-19 policy Journal of Economic Behavior and Organization. 190 2021 191 200 10.1016/j.jebo.2021.07.026 34566218 Christensen D. Dube O. Haushofer J. Siddiqi B. Voors M. Community-based crisis response: Evidence from sierra leone’s ebola outbreak AEA Papers Proceedings 110 2020 260 264 10.1257/pandp.20201015 Cordova A. Methodological Note: Measuring Relative Wealth using Household Asset Indicators. AmericasBarometer Insights 6 2009 Vanderbilt University, LAPOP 1 9 De la O A. Crafting Policies to End Poverty in Latin America: The quiet Transformation 2015 Cambridge University Press Cambridge 10.1017/CBO9781316105528 Delhey J. Newton K. Welzel C. How general is trust in “most people”? Solving the radius of trust problem American Sociological Review 76 5 2011 786 807 10.1177/0003122411420817 Dingel J. Neiman B. How many jobs can be done at home? Journal of Public Economics 189 2020 104235 10.1016/j.jpubeco.2020.104235 Durante R. Guiso L. Gulino G. Asocial capital: civic culture and social distancing during COVID-19 Journal of Public Economics. 194 104342 2021 10.1016/j.jpubeco.2020.104342 Eichengreen B. Aksoy C. Saka O. Revenge of the experts: Will COVID-19 renew or diminish public trust in science? Journal of Public Economics. 193 104343 2021 10.1016/j.jpubeco.2020.104343 Fiszbein, A., Schady, N.R., 2009. Conditional Cash transfers: Reducing Present and Future Poverty. World Bank Policy Research Report. Washington, D.C.: World Bank Group. Available at: http://documents.worldbank.org/curated/en/914561468314712643/Conditional-cash-transfers-reducing-present-and-future-poverty. Garay C. Social Policy Expansion in Latin America. Cambridge: 2016 Cambridge University Press Garrote, D., Parra, N.G., Ozden, C., Rijkers, B., Viollaz, M., Winkler, H., 2020. Who On Earth Can Work from Home? Policy Research Working Paper WPS 9347, COVID-19. Washington, D.C.:World Bank. Available at http://documents.worldbank.org/curated/en/225881596202941026/Who-on-Earth-Can-Work-from-Home. Gelfand, M., Jackson, J., Pan, X., Nau, D., Pieper, D., Denison, E., Dagher, M., Van Lange, P., Chiu, Ch., Wang, M., 2021. The relationship between cultural tightness–looseness and COVID-19 cases and deaths: a global analysis. Lancet Planetary Health 5(3), E135–E144. doi:10.1016/S2542-5196(20)30301-6. Gentilini U. Almenfi M. Dale Palacios R. Natarajan H. Galicia Rabadan G.A. Okamura Y. Blomquist J. Abels M. Demarco G. Santos I. Social Protection and Jobs Responses to COVID-19: A Real-Time Review of Country Measures 2020 World Bank. UNICEF Google LLC, 2021. “Google COVID-19 community mobility reports”. Available at: https://www.google.com/covid19/mobility/. Accessed on 9/15/2020. Hakhverdian A. Mayne Q. Institutional trust, education, and corruption: a micro-macro interactive approach Journal of Politics 74 3 2012 739 750 10.1017/S0022381612000412 Hale, T., Angrist, N., Kira, B., Petherick, A., Phillips, T., & Webster, S. 2022. Variation in government responses to COVID-19. Blavatnik School of Government Working Paper. Available at https://www.bsg.ox.ac.uk/research/publications/variation-government-responses-covid-19. Huber E. Stephens J. Democracy and the Left: Social Policy and Inequality in Latin America 2012 Chicago: University of Chicago Press Kapiszewski D. Levitsky S. Yashar D. The Inclusionary Turn in Latin American Democracies 2021 Cambridge: Cambridge University Press 10.1017/9781108895835 Knack S. Keefer P. Does social capital have an economic payoff? A cross-country investigation Quarterly Journal of 112 4 1997 1251 1288 10.1162/003355300555475 La Porta R. Lopez-de Silanes F. Shleifer A. Vishny R. Trust in large organizations American Economic Review 87 2 1997 333 338 The Americas Barometer by the LAPOP Lab. www.vanderbilt.edu/lapop. Accessed: 15/09/2020. Letki N. Investigating the roots of civic morality: trust, social capital, and institutional perfor- mance Polit. Behav. 28 2006 305 325 10.1007/s11109-006-9013-6 Letki N. Trust in newly democratic regimes Uslaner, E. The Oxford Handbook of Social and Political Trust 2018 Oxford:Oxford University Press 335 356 10.1093/oxfordhb/9780190274801.013.28 Marien S. Werner H. Fair treatment, fair play? the relationship between fair treatment perceptions, political trust and compliant and cooperative attitudes cross-nationally European Journal of Political Research 58(1), 72-95 2018 10.1111/1475-6765.12271 Mattes A. Moreno Social and political trust in developing countries: Sub- Saharan Africa and Latin America Uslaner, E. The Oxford Handbook of Social and Political Trust 2018 Oxford: Oxford University Press 357 382 McKenzie, D., 2005. Measuring inequality with asset indicators. Journal of Population Economics 18, 229–260. doi:10.1007/s00148-005-0224-7. Miguel E. Gugerty M.K. Ethnic diversity, social sanctions, and public goods in Kenya Journal of Public Economics 89 11–12 2005 2325 2368 10.1016/j.jpubeco.2004.09.004 Morris S. Klesner J. Corruption and trust: Theoretical considerations and evidence from Mexico Comparative Political Studies. 43 10 2010 1258 1285 10.1177/0010414010369072 Newton K. Zmerli S. Three forms of trust and their association European Political Science Review 3 2 2011 169 200 10.1017/S1755773910000330 Newton K. Stolle D. Zmerli S. Social and Political Trust Usalner E.M. The Oxford Handbook of Political Trust 2018 Oxford University Press 37 57 ISSN 978–0–19–027480–1 Painter M. Qiu T. Political beliefs affect compliance with government mandates Journal of Economic Behavior and Organization 185 2021 688 701 10.1016/j.jebo.2021.03.019 36540423 Plohl N. Musil B. Modeling compliance with COVID-19 prevention guidelines: the critical role of trust in science Psychology, Health & Medicine 26(1), 1-12 2021 10.1080/13548506.2020.1772988 Pribble J. Welfare and Party Politics in Latin America 2013 Cambridge: Cambridge University Press Ravallion, M., 2020. Pandemic policy in poor places. Center for Global Development Note. Available at https://www.cgdev.org/publication/pandemic-policies-poor-places. Mathieu, E., Ritchie, H., Rodés-Guirao, L., Appel, C., Giattino, C., Hasell, J., Macdonald, B., Dattani, S., Beltekian, D., Ortiz-Ospina, E., Roser, M. 2020. Coronavirus Pandemic (COVID-19). Published online at OurWorldInData.org. Retrieved from: https://ourworldindata.org/coronavirus. Robalino, David A., 2020. The COVID-19 Conundrum in the Developing World: Protecting Lives or Protecting Jobs? IZA Discussion Papers 13136. Institute of Labor Economics (IZA). Schneider C. Dryhurst S. Kerr K. Freeman A. Recchia G. Spiegelhalter D. Van der Linden S. COVID-19 risk perception: a longitudinal analysis of its predictors and associations with health protective behaviours in the United Kingdom Journal of Risk Research 24 (3-4), 294-313 2021 10.1080/13669877.2021.1890637 Searing E. Love thy neighbor? Recessions and interpersonal trust in Latin America Journal of Economic Behavior and Organization 94 2013 68 79 10.1016/j.jebo.2013.07.010 Shachat J. Walker M. Wei L. How the onset of the COVID-19 pandemic impacted pro-social behaviour and individual preferences: experimental evidence from China Journal of Economic Behavior and Organization. 190 2021 480 494 10.1016/j.jebo.2021.08.001 34642514 Stampini, M., Tornarolli, L., 2012. The growth of conditional cash transfers in Latin America and the Caribbean: did they go too far? IDB Policy Brief 185. URL https://publications.iadb.org/en/growth-conditional-cash-transfers-latin-america-and-caribbean-did-they-go-too-far. Sugiyama N.B. The diffusion of conditional cash transfer programs in the Americas Global Social Policy 11 2–3 2011 250 278 10.1177/1468018111421295 Uslaner E. The Oxford Handbook of Social and Political Trust 2018 Oxford: Oxford University Press. ISSN 978–0–19–027480–1 Van de Weerd W. Timmermans D. Beaujean D. Oudhoff J. Steeenbergen J. Monitoring the Level of Government trust, Risk Perception and Intention of the General Public to Adopt Protective Measures During the Influenza a (H1N1) Pandemic in the Netherlands BMC Public 11 2011 575 10.1186/1471-2458-11-575 Vinck P. Pham P. Bindu K. Bedford J. Niles E. Institutional trust and misinformation in the response to the 2018–19 Ebola Outbreak in North Kivu, DR Congo: a population-based survey Lancet Infectious Diseases 19 5 2019 529 536 10.1016/S1473-3099(19)30044-1 30928435 Vyass S. Kumaranayake L. Constructing socioeconomic status indexes: How to use principal component analysis Health Policy Plan 21 6 2006 459 468 10.1093/heapol/czl029 17030551 Wachinger, G., Renn, O., Begg, C., Kuhlicke, C., 2012. The risk perception paradox – Implications for governance and communication of natural hazard. Risk Analysis 33(6), 1049-1065. doi:10.1111/j.1539-6924.2012.01942.x. Weitz-Shapiro R. Winters M. Can citizens discern? information credibility, political sophisti- cation, and the punishment of corruption in Brazil Journal of Politics 79 1 2017 60 74 10.1086/687287 Wong C. Jensen O. The paradox of trust: perceived risk and public compliance during the COVID-19 pandemic in Singapore Journal of Risk Research 23(7-8), 1021-1030 2020 10.1080/13669877.2020.1756386 Wright A.L. Sonin K. Driscoll J. Wilson J. Poverty and economic dislocation reduce Compliance with COVID-19 shelter-in-place protocols Journal of Economic Behavior and Organization 80, 544-554 2020 10.1016/j.jebo.2020.10.008 You Trust and corruption Uslaner, E. The Oxford Handbook of Social and Political Trust 2018 Oxford University Press Oxford 473 496 10.1093/oxfordhb/9780190274801.013.22 Zmerli, S., Newton, K. 2017. Objects of political trust: Scales and hierarchies. In: Zmerli, S., van Der Meer, T. (Eds.). Hanbook on Political Trust. Cheltenham: Edward Elgar, pp. 104-124. doi:10.4337/9781782545118.00017.
PMC009xxxxxx/PMC9786527.txt	==== Front Ann Inst Stat Math Ann Inst Stat Math Annals of the Institute of Statistical Mathematics 0020-3157 1572-9052 Springer Japan Tokyo 36590375 860 10.1007/s10463-022-00860-4 Article Generation of all randomizations using circuits Pesce Elena [email protected] 1 Rapallo Fabio [email protected] 2 Riccomagno Eva [email protected] 3 Wynn Henry P. [email protected] 4 1 grid.483613.b 0000 0001 1193 5897 Swiss Re Institute, Swiss Re Management Ltd, Mythenquai 50/60, 8022 Zurich, Switzerland 2 grid.5606.5 0000 0001 2151 3065 Department of Economics, Università di Genova, Via F. Vivaldi 5, 16126 Genoa, Italy 3 grid.5606.5 0000 0001 2151 3065 Department of Mathematics, Università di Genova, Via Dodecaneso 35, 16146 Genoa, Italy 4 grid.13063.37 0000 0001 0789 5319 London School of Economics, London, WC2A 2AE UK 23 12 2022 2023 75 4 683704 13 7 2022 1 11 2022 17 11 2022 © The Institute of Statistical Mathematics, Tokyo 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. After a rich history in medicine, randomized control trials (RCTs), both simple and complex, are in increasing use in other areas, such as web-based A/B testing and planning and design of decisions. A main objective of RCTs is to be able to measure parameters, and contrasts in particular, while guarding against biases from hidden confounders. After careful definitions of classical entities such as contrasts, an algebraic method based on circuits is introduced which gives a wide choice of randomization schemes. Keywords Algebraic statistics and combinatorics A/B testing Bias and confounders Big data Design of experiments issue-copyright-statement© The Institute of Statistical Mathematics, Tokyo 2023 ==== Body pmcIntroduction There are ways in which a regression model can be biased because of the neglect of hidden variables, sometimes called hidden confounders. To some extent these biases can be removed using randomization. A major source of conceptual difficulty is the continuing distinction between passive observation, characterized by the terms “observational study” and controlled experiment. In addition this distinction is flavored by different intellectual traditions. In most fields a controlled experimental design is conceived as an intervention. Thus one talks about setting the level of a variable X, or applying a treatment or treatment combination. Rather than interfere too much with the state of Nature one may simply select a value of X which is already in a population, such as selecting a subject of a particular age. Stratification is in this category as is “matching”, observing (or treating) a collection of subjects who are close in terms of some multivariate metric applied to the possible confounders. “Natural Experiments” exploit opportunities where Nature has unwittingly designed an experiment for us. For a very thorough compendium of experimental design methodology both as intervention and as selection, see Dean et al. (2015). Traditions in agriculture and socio-medical sciences have stressed the role of randomization, and indeed the method has been described as one of the greatest contributions of statistics to scientific methodology; a major review is Cox (2009) which goes a long way toward updating earlier discussions, such as Kempthorne (1955). After a long period in which factorial and optimum controlled experiments may be seen to have had a dominant role, influenced by success in product design and quality improvement, randomization is making a come back, if indeed it ever left the limelight. It is now used extensively outside its traditional areas of clinical trials under the generic term randomized control trials, RCT. Notably, there is a fast growing application to experiments in social media, under the heading A/B testing in on-line marketing, see Kohavi and Longbotham (2017), and to socio-technical experiments, such as smart metering in homes and transport, see e.g., Guzowski et al. (2014). Other important developments are in the field of “big data”, where data are often collected without experimental design being used at all, so that biases can be a serious impediment to model building, see Drovandi et al. (2017), Pesce et al. (2019, 2022). There seems to be no doubt that in nearly all fields the removal of biases in modeling is a major reason to randomize. The question then remains as to whether the randomization, or rather the randomization distribution, is to be used in the analysis, e.g., probability statements are made based on the randomization, for example, using nonparametric tests, or whether randomization should only be used in the design, e.g., for bias reduction. The latter approach is probably more common and is adopted here. A compromise position is a minimax approach which is closely related to the use of randomization in finite population sampling, see Scott and Smith (1975), Stenger (1979), Stigler (1969), Wynn (1977). Our approach can be considered a contribution to the subtle relationship between randomization and combinatorial design, see Bailey and Rowley (1987). It is based on the theory of circuits, which are already studied in operations research (Simões Pereira 1975) and algebraic statistics (Fontana et al. 2022). The better known extensions of simple RCT such as block randomization, stratified randomization and the less covered hierarchical randomization are covered by our methods, and we shall return to this claim in the last section. After a straightforward formulation of the problem, we formally define valid randomization schemes in Sect. 4, followed by a short discussion on analysis in Sect. 5. Sections 6 and 7 are the main developments, with Sect. 6 describing a sufficient condition under which unions of non-negative binary circuits give a valid randomization. Section 7 gives some special conditions. Final considerations in Sect. 8 conclude the paper. A/B testing Some of the disparate interpretations of randomization can be understood from a simple A/B testing (RCT) experiment, which is typically used to assess the difference between the effect of two treatments A and B with effect parameters θA and θB, respectively. That is, we want to estimate ϕ=θA-θB. A standard model for a response variable Y is to write for subjects i and j receiving treatments A and B, respectivelyYAi=θA+δAi,i=1,…,nA,YBj=θB+δBj,j=1,…,nB where nA,nB are the respective sample sizes and δAi,δBj are unit effects of other influences, be they errors of measurement or other (hidden) factors effects. YAi and YBj are therefore specializations of Y for the two sub-populations A and B. The naive estimate of the treatment difference isϕ^=θ^A-θ^B. Here the estimates of θA and θB are given by the respective sample means:θ^A=Y¯A·,θ^B=Y¯B·, where for instance Y¯A· is the usual notation for the average of measurements over group A. The standard argument, and this is probably also the common sense argument of non-experts, is that if we randomize then the difference between the mean values of the deviations due to other factors will cancel out: δA·-δB·, will be approximately zero and will not perturb ϕ^. Of course, if δAi,δBj are random with standard assumptions then ϕ^ is both the least squares estimate and the best linear unbiased estimate of ϕ. A critical question is: what does the model mean, both scientifically and predictively? What are θA,θB and ϕ? In other words, do parameter values refer to the finite population from which the sample was taken or to which the treatment were applied? Or is there some larger population of which the population of units under study is a subpopulation, such as all present and future subjects who may benefit from a vaccination decision based on the results of the experiment? Or, are A and B a “crucial experiment”, to decide between two scientific theories? These questions are important also with the A/B testing experiments on people using social media. The commercial opportunities in terms of the use of huge (big) data sets come with a risk of bias arising from any number of demographic and operations factors. It is almost impossible to describe the population of social media users but if bias can be removed in some simple way then the estimates can genuinely reflect peoples’ choices and behavior. A naive but rather universal conclusion is something like: after randomization we can use the model. This is expressed as part of expert advice: make sure you randomize your blocks. On the one hand this paper takes this simple approach, but on the other introduces a special technique, based on circuits, to decompose an experiment into mutually exclusive blocks in each of which randomization can be carried out separately. Some solutions comprise recognizable combinatorial designs, such as matching and stratification. All the others can be derived from the circuits which can be computed from running the program 4ti2 (4ti2 team 2018). Our approach provides a full solution to the problem of block randomization to control bias, up to the computational feasibility, see Sect. 6.1. Contrasts Consider an experiment giving a random sample Y1,…,Yn and the following: Definition 1 A linear function Z=∑i=1nciYi with fixed coefficients {ci} is called an empirical contrast if ∑i=1nci=0. In the A/B case randomization is particularly suited to situations in which standard estimates are unaffected by a uniform shift of the observations, which is then subtracted out. Now consider a standard regression model in the formY(x)=∑j=1pθjfj(x)+ϵ, for functions {fj(x)}, x a generic point in some design space X, for parameters {θj}, and ϵ a random error with the usual assumptions (zero mean and constant variance). An experimental design D={x(i),i=1,…,n}, with sample size \|D\|=n, has design matrixX={fj(x(i))} with dimension n×p, and we express the standard regression set-up by:μ=E(Y)=Xθ, where θ is a vector of parameters with length p and E is the expectation. Definition 2 follows standard terminology in regression models and design of experiments, see Das and Jain (1970). Definition 2 For a standard regression model a parametric contrast is defined as the expectation of an empirical contrast. In the following we exemplify the basic idea to divide experiment into disjoint blocks in each of which we randomize, and then combine the results. Example 1 (22 experiment) We consider a simple example from linear regression, namely a 22 factorial design problem, with ±1 levels and no replication (for simplicity). We take the model without an interactionE(Y)=θ0+θ1x1+θ2x2, so that design matrix isX=1111-1-111-11-11. If we randomize a large population and uniformly apply the four combination of the design, {±1,±1}, the potential bias effect will be negligibly small because the estimators of the θ-parameters are unbiased. But there is an alternative. Split the population into two groups, randomize each separately and apply the controls (x1,x2)={(1,1),(-1,-1)} to the first group and {(1,-1),(-1,1)} to the second group. Then we can estimate θ1+θ2 from the first group and θ1-θ2 from the second group. Combining these estimates gives the same result as if we randomized over the whole 22 experiment. Note that the parameters θ1 and θ2 and their estimates are already respectively parametric contrasts and empirical contrasts, with contrast coefficients equal to c=14(1,-1,1,-1)T and c=14(1,-1,-1,1)T, respectively. This can be seen as splitting the 23 experiment into two (randomized) A/B experiments. Writing a model in contrast form In the case of the orthogonal design described above the X-matrix takes the formX=[ξ:X1], where ξ is the n-vector of ones, for the constant (intercept) term, and X1 is a matrix with dimension n×(p-1) orthogonal to ξ, that is ξTX1=0. We describe such an X-matrix as being in contrast form. All empirical and parametric contrasts are derived from X1. Thus we can prove the following lemma. Lemma 1 For a regression model with μ=E(Y)=E(X~θ), written in contrast form X~=[ξ:X1] the set of all parametric contrasts is {cTμ:cTX1=0andξTc=0}. Proof This follow since E(cTY)=cT[ξ:X1]θ=(cTξ,cTX1)θ. □ Notice that from any model with integer design matrix X it is always possible to derive a reparametrization with design matrix X~ written in contrast form. In Sect. 6, we will use the vector ξ and we will exploit its orthogonality to X1 to study the connections between randomizations and circuits. Note that the assumption of integer design matrix X is made here only to simplify the computation of the circuits introduced in Sect. 6. The theory here is valid for design matrices with rational entries. A design matrix with rational entries can be multiplied by a constant, namely the least common multiple of the denominators, to obtain a matrix with integer entries whose columns generate the same vector space. Lemma 2 Every model Y=Xθ+ϵ including the intercept can be transformed to contrast form as Y=X~ϕ+ϵ, where X~=[ξ:X1] is full-rank and has the same column space as X and ξTX1=0. Proof We can easily determine the reparametrization which the transformation requires. Starting with:X~ϕ=Xθ, we simply solve for ϕ:ϕ=(X~TX~)-1X~TXθ. □ From Lemma 2, a design matrix X with column space containing the vector ξ=(1,1,…,1)T can be transformed to contrast form. The term contrast is especially prevalent in Analysis of Variance (ANOVA) models, that is additive models for qualitative factors in which each level of each factor provides a parameter. The classical notation for a two-way I×J table with two factors is that the additive model would have parameters αi,(i=1,…,I) and βj,(j=1,…,J) and the model for the observations Yij is1 Yij=αi+βj+ϵij, where {ϵij} are the random errors with standard assumptions. We show below how the reparametrization to obtain a model in contrast form works with an example for a model as in Eq. 1. Example 2 Let I=J=2. By using indicator variables and setting θ=(α1,α1,β1,β2)T we write the model in regression form, E(Y)=Xθ whereX=1010100101100101. This X-matrix is not in contrast form, but it can be transformed into contrast form:X~=11111-11-111-1-1. From this, the reparametrization is:ϕ0=12(α1+α2+β1+β2),ϕ1=12(α1-α2),ϕ2=12(β1-β2). We have limited the analysis to the decomposition of X~ into [ξ:X1] since for randomization we are interested in the decomposition of the vector ξ, but the results in this section and many results about the circuit bases in the next sections could be written in general for a decomposition of X~ into [X2:X1] with X2TX1=0. Note that when a full-rank matrix X~ is decomposed into [ξ:X1], also the matrix X1 is full-rank. To avoid trivialities, we also assume that all the rows of the matrix X1 are not null, i.e., each design point is involved in at least one contrast. Valid randomizations Using the representation of the design matrix in contrast form we can provide a catalogue of valid randomization systems to address the question stated earlier in Sect. 1.1 in the framework of A/B experiments. The elements of the catalogue can be computed and in the case of unimodular X1 matrix (see Sect. 7) this catalogue is complete. The separation into blocks is a partition of the observations so that there are at least two observations in each element of the partition, as described by the following definitions giving the only relevant randomizations to study contrasts. Definition 3 For observations Yi,(i=1,…,n) a potential randomization system R is a set partition of N={1,2,…,n}, namely a decomposition of N into disjoint exhaustive subsets, R1,…,Rk, called blocks, of size 2 or more: ⋃i=1kRi=N Ri∩Rj=∅,1≤i<j≤k \|Ri\|≥2,i=1,…,k Definition 4 For a regression model and experimental design Dn with sample size n, a design matrix in contrast form [ξ:X1] and a potential randomization system {R1,…,Rk}, let z(i)=(zi,1,…,zi,n) the binary vectors defined byzi,j=1,i∈Rj0,i∈N\Rj. The potential randomization system is a valid randomization system if z(i) is orthogonal to X1, i.e., (z(i))TX1=0, for all i=1,…,k. The case where R=N, we refer to as full randomization. The next two examples are familiar in the sense that the orthogonal blocks are easily associated with addition factors or parameters in an orthogonal design. The third example may be less familiar. Factorial fractions We consider a 23 factorial experiment for main effects. The standard X-matrix is already in contrast form:XT=111111111111-1-1-1-111-1-111-1-11-11-11-11-1. In addition to a full randomization, represented by {1,2,3,4,5,6,7,8}, there are two different randomization systems and we list the Rj partitions for each: {1,4,6,7},{2,3,5,8}; {1,8},{2,7},{3,6},{4,5}. These two distinct randomizations of this example correspond to familiar decomposition into blocks based on abelian groups (see e.g., Box et al., 1978). The first arrives from a 23-1 experiment with defining contrast subgroup in classical notationI=ABC. The second corresponds to the 23-2 with subgroupI=AB=BC=AC. For those more familiar with the algebraic design of experiments, these solutions are the point ideal corresponding respectively to the solutions of(1):x1x2x3=±1,and(2):(x1x2,x2x3)=(±1,±1). Tables and Latin squares Consider an I×I table with the usual additive model. A Latin square based on the table has the usual definition. If I=3 there are two mutually orthogonal Latin squares; in traditional notation:ABCCABBCAabcbcacab Each square gives a different valid randomization based on the letters. Labeling the observations left-to-right and top-to-bottom the respective blocks are (ignoring commas){159},{267},{348},{168},{249},{357}. We state the general result without proof and in the terminology of this example. Lemma 3 For an I×I additive Analysis of Variance model a set of mutually orthogonal Latin squares provides a set of alternative valid randomizations. k-out-of-2k choice experiments Choice experiments are those in which subjects are asked to score a selection of attributes from a portfolio of attributes. Models are fitted to experimental data in an effort to discover subjects’ (hidden) preference order. Suppose there are n=4 attributes and each subject is offered k=2 attributes, labeled 1, 2, 3, 4. There are six selection pairs{1,2},{1,3},{1,4},{2,3},{2,4},{3,4}. An additive preference model has (without replication) the six values Yi,j with the modelYij=αi+αj+ϵi,j(i,j=1,2,3,4;i<j). We are interested in contrast αi-αj, because their estimates would yield an estimated preference order. In this case:X=110010101001011001010011. This gives a choice of X1:X1T=-1000010-1001000-1100, and the randomization: {1,6},{2,5},{3,4}, where the integers refer to selection pairs. Analysis The informal approaches we have taken is that, for large samples randomization has approximately the effect of introducing a block parameter. Our condition of orthogonality in the definition of valid randomization and as exemplified, has so far ignored the fact that in standard terminology blocks do not have to be orthogonal. Indeed, there is rich theory of balanced incomplete blocks (BIBD) both from combinatorial and from optimal design theory. We note here some basic facts about orthogonal versus non-orthogonal blocks. For orthogonal designs we set up a model in which every binary vector orthogonal to the X1 matrix is allocated a block parameter, then only under orthogonality is the usual Least Square Estimate (LSE) of the θ-parameters the best and there is no bias of these estimates from the block effects. In the non-orthogonal blocks design case, if we use the LSE of the θ-parameters assuming that the block parameters are zero, when they are not, then the block parameters introduce bias. In the non-orthogonal blocks case the “proper” LSE estimate of the θ-parameters in the presence of the block parameters, will be unbiased but will have higher variances than in case (2) above. This can be expressed by the Loewner ordering: one covariance matrix is “smaller” than the other if the difference is non-negative definite. Models with non-orthogonal blocks with a specified block effect, require some effort to model or at least interpret the block affect, for example the effect of day if the experiment is conducted over days. In such cases a bias model is required. But where bias is caused by hidden, unspecified, confounders, such a bias model seems somewhat artificial. The effects are too artificial to model but sufficiently present that we prefer orthogonality. Circuit basis for randomization In this section, we introduce the notion of circuits of a matrix which allows a novel approach to the problem of randomization. The proposed analysis, based on tools from Algebraic Statistics, leads to the enumeration of all possible randomization schemes. In this setup a randomization is given by the decomposition of the vector ξ=(1,…,1)T into binary vectors:2 ξ=ξ1+⋯+ξk where each vector ξh∈{0,1}n satisfies ξhTX1=0, h=1,…,k. Such binary vectors ξh are called binary randomization vectors. Next, we introduce the circuits and their main properties. When all randomization vectors cannot be decomposed into binary vectors with smaller support we have a non-decomposable randomization. Definition 5 Given a randomization of ξ into binary vectors as in Eq. (2), the vector ξh is a non-decomposable randomization vector if there is no decomposition ξh=ξh,1+ξh,2 with ξh,1TX1=0 and ξh,2TX1=0. If all the vectors ξ1,…,ξk are non-decomposable, Eq. (2) defines a non-decomposable randomization. Let A be an integer-valued matrix with d rows and n columns. For our purposes, we can assume that A=X1T. Let u∈Zn be an integer-valued vector, u+ be the positive part of u, namely ui+=max(ui,0), i=1,…,n, and u- be the negative part of u, namely ui-=-min(ui,0), i=1,…,n, so that u=u+-u-. Moreover, denote with supp(u) the support of u, i.e.,supp(u)={i∈{1,…,n}:ui≠0}. Definition 6 A circuit of A is an integer-valued vector u in ker(A), i.e., Au=0, with the following minimality properties: u has minimal support, i.e., there is no other circuit v with supp(v)⊂supp(u). u is irreducible: if v is an integer-valued vector in ker(A) with supp(v)=supp(u), then v=ku for some k∈N. Definition 7 The set of all circuits of the matrix A is named the circuit basis of A and is denoted with C(A). The circuit basis C(A) is always finite. The minimal support property gives rise to a number of interesting properties of C(A). We recap in the following proposition the special features of the circuits we will use for describing randomization. For the proofs and further details the reader can refer to Sturmfels (1996). Proposition 1 Let A be an integer-valued matrix with dimensions d×n and suppose that rank(A)=d. The circuit basis C(A) is subset compatible, i.e., for a sub-matrix A′ with n′<n columns of A, the circuit basis of A′ is given by the circuits in C(A) whose support is contained in the n′ columns. The cardinality of the support of a circuit in C(A) is at most d+1. Each vector v of ker(A) can be written as rational non-negative linear combination of circuits, i.e., v=∑h=1n-dqhuh,qh∈Q+ and the uh are conformal with v. The term “conformal” in Item (3) of Proposition 1 means that supp(uh+)⊂supp(v+) and supp(uh-)⊂supp(v-). The first key observations for randomization follow directly from the fact that a circuit lies in ker(A). Lemma 4 Any non-negative binary circuit of A=X1T provides a randomization vector. Proof When a non-negative binary circuit ξ1 gives a valid randomization, then also ξ2=ξ-ξ1 is a binary non-negative vector in ker(A) so that the decomposition ξ=ξ1+ξ2 is a valid randomization. □ Note that the vector ξ2 in the proof may be a circuit itself (and in such a case we call ξ=ξ1+ξ2 a non-decomposable randomization), or not. In the latter case, the vector ξ2 can be decomposed into the sum of non-negative circuits by virtue of Proposition 1, Item (3). The decomposition of ξ in Eq. (2) and the argument above show that valid randomizations generate a lattice, partially ordered by set inclusion, indeed: (1) circuits sit at the most refined level of the lattice and (2) less refined randomization schemes are obtained by merging two lattice elements into their join. This connection with lattice (and matroids) is taken up again in the discussion section. From Proposition 1, Item (3), and Lemma 4, we see that the circuit basis, and in particular the set of non-negative circuits, is the natural tool to find valid non-decomposable randomizations. In general, if the vector ξ can be written as the sum of binary non-negative circuits we have a valid randomization. The main problem posed in this paper is to provide conditions for when the converse holds, that is to provide classes of experimental designs for which every randomization vector ξh is a circuit. In the next section we will describe an important class, here we have a useful sufficient condition. Lemma 5 If ξ1 is a non-negative binary randomization vector with two nonzero elements (#supp(ξ1+)=2), then it is a circuit of X1T. Proof In view of Proposition 1, Item 3, it is enough to prove that there is no circuit ξ1 with exactly one nonzero element. By contradiction, suppose that such a vector ξ1 exists and, without loss of generality, suppose that ξ1=(1,0,…,0). Since ξ1 is in the kernel of X1T, we have X1Tξ1=0 and this implies that the first column of X1T is a column of zeros. This is in contradiction with the fact that all rows of X1 are not zero. □ Thus, for every ξ1-vector in example covered by Lemma 5, there are two rows of X1T which have opposite signs. This is the case in Sect. 4.3 which yields the following result. Corollary 1 Any k-out-of-2k choice experiment is a valid randomization with blocks of size 2. Proof For a k-out-of-2k experiment we can construct an X matrix with rows corresponding to k-tuples and the rows in lexicographic order. Then as for the example in Sect. 4.3 we pair them: the first with the last, second with the second to last and so on, assigning -1 and +1 respectively, to construct the X1 matrix. Let n=2kk, then the valid randomization blocks are the selection pairs:{1,n},{2,n-1},…,{n/2,n/2-1}, which follows because X1 is of the type discussed in Lemma 5. □ This shows that a valid randomization with binary vectors each with two nonzero binary vectors can be found by inspecting the list of all circuits. Computation of circuits To find the randomization systems from the circuit basis, we start from the design matrix X, we write it in contrast form X~, and we extract the contrast matrix X1 as described above. The actual computation of the circuits of the matrix X1 can be done with the software package 4ti2, see 4ti2 team (2018). In 4ti2 there is a function called circuits to compute the circuits of an integer matrix. The algorithms to compute circuits in 4ti2 belong to the class of combinatorial algorithms, and thus there is a limitation on the size of the matrices for which the computation of the circuit is actually feasible. In our experiments, problems with a set of points up to 50 are easily processed, but the execution time increases fast with the number of points. However, all the contrast matrices illustrated in this paper have been processed by 4ti2 in less than 0.1 seconds. 4ti2 is now available also within the symbolic software Macaulay2, see Grayson and Stillman (2019), and there are R packages available which allow the communication between R and Macaulay2, leading to a flexible use of the symbolic computations into statistical analysis, see Kahle et al. (2020). Example 3 Using the function circuits for the contrast matrix of the 3-out-of-6 problem, we obtain three circuits as expected001001010100100010. Example 4 Computing the circuits for the 23 design with contrasts on the main effects, we obtain the circuits described in the previous sections. The 4ti2 output consists of 20 circuits, 6 of which are non-negative:000110000010010001000010011010011000000110010110. This yields the two randomization schemes{1,4,6,7},{2,3,5,8}and{1,8},{2,7},{3,6},{4,5} already discussed. Here, there is only one valid randomization based on 2-ers and only one valid randomization based on 4-ers. (The term n-er is a colloquial term for an entity of size n.) With the aid of the circuits we are able to analyze also more complex models where the number of randomization systems is relatively large. Example 5 In the case of 24 design with contrasts on the main effects, the contrast matrix is:X1T=11111111-1-1-1-1-1-1-1-11111-1-1-1-11111-1-1-1-111-1-111-1-111-1-111-1-11-11-11-11-11-11-11-11-1, and the situation becomes more complex. Although 0.02 seconds are enough to obtain the whole set of 456 circuits, the non-negative circuits are now 48 but there are also non-binary circuits with entries equal to 2. Selecting the binary circuits reduces to 32 circuits: 8 circuits with support on two points give a unique randomization based on 2-ers; with the remaining 24 circuits on 4 points we can construct 30 valid randomizations. Each circuit on 4 points is used in 5 possible randomizations. For instance with the circuitc=0000011010010000 one can define 5 randomizations, reported in Fig. 1. Fig. 1 The 5 randomizations for the 24 configuration in Example 5 containing the circuit c=(0,0,0,0,0,1,1,0,1,0,0,1,0,0,0,0) With a large choice of randomization schemes the problem arises as to which to choose. This is discussed briefly in Sect. 8. Totally unimodular X1 Although the factorial design and Latin square examples can be considered well-known, because of their orthogonality properties, example in Sect. 4.3 may be less so. So we may ask what is the property of X1T for which the full valid randomization system can be found as a set of circuits. Definition 8 A totally unimodular matrix A is one for which all square sub-matrices (including itself if square) have determinant 0, 1, or -1. Theorem 1 Let A=X1T be the design/model matrix of regression model in contrast form and suppose A is totally unimodular. Then every valid randomization is based on circuits. The proof is in two parts. First we need the following lemma, whose proof is based on some technical results from the algebraic theory of toric ideals and Gröbner bases. In order to maintain the focus on the problem of randomization, we do not recall here all the formal definitions of the objects needed in the proof, for which the reader can refer to, e.g., Sturmfels (1996). Lemma 6 For a totally unimodular matrix A all non-negative circuit vectors are binary. Proof In this statement, the circuits should be seen as represented by the so-called binomials, that is for each circuit u=u+-u- we consider n “dummy” variables x1,…,xn and the binomial associated to u is defined as:xu+-xu-. These binomials generate a toric ideal I(A). This ideal is very widely studied, for example in algebraic statistics it is the starting point for Markov Chain Monte Carlo simulation for testing hypotheses on multinomial contingency tables, see Diaconis and Sturmfels (1998). Now, if A is totally unimodular then it is known that the initial ideal in(I(A)) is generated by square-free binomials for any given term-order (required to define a Gröbner basis), see Sturmfels (1996). The initial ideal in(I(A)) of the ideal I(A) is the ideal generated by the leading terms of the polynomials in I(A). Thus, all the binomials in the Universal Gröbner basis U(I(A)) have square-free leading terms. Finally, the non-negative circuits are elements of U(I(A)), viewed as binomials of the form xu-1. The leading term is always xu, it is square-free, and therefore u is binary. □ To complete the proof of Theorem 1 we also need the following result. Lemma 7 If the contrast matrix A=X1T in a regression model is totally unimodular then every non-decomposable randomization vector ξ is a circuit. Proof This is by contradiction. Let ξ1 be a (non-negative binary) non-decomposable randomization vector and suppose it is not a circuit. Since ξ1∈ker(A), by Proposition 1, Item 3, ξ1has a representation as a non-negative linear combination of circuits u1+⋯+uk. Take one of such circuits uh. Its support is strictly contained in supp(ξ1) and note that #supp(ξ1)-#supp(uh)>1, because ξ1 is not a circuit and there are no circuits with support on one point. Moreover, the circuit uh is binary by Lemma 6. So there is a refinement given by ξ1=uh+(ξ1-uh), which contradicts ξ1 being non-decomposable. □ Proof (of Theorem 1) Letξ=ξ1+⋯+ξk, be a valid randomization. If it is non-decomposable, then the vectors ξ1,…,ξk are circuits by Lemma 7. If the randomization is decomposable, each vector ξh can be decomposed into the sum of non-negative circuits, by Proposition 1, Item 3. By Lemma 6 such circuits are binary and they form a non-decomposable randomization. □ The best known example of a totally unimodular matrix is generated by a directed graph G(V, E). The rows are indexed by vertices and the columns by directed edges with the following rule for entries: if the edge is e=(i→j) then entries Ai,e=1,Aj,e=-1 and all other entries in column e are zero. For A to be an X1 matrix we need it to be (row) orthogonal to ξ=(1,1,…,1)T, this requires that for any vertex the number of in-arrows and the number of out-arrows must be the same. Example 6 Let \|V\|=5,\|E\|=15 and the directed edges (leaving out commas):12,13,14,23,24,25,34,35,31,45,41,42,51,52,53. In this example A=X1T is11100000-10-10-100-10011100000-10-100-10-10011100000-100-10-10-10011100000000-10-10-100111. Fig. 2 The directed graph on 5 points in Example 6 The graph for this example is pictured in Fig. 2. For the X1 matrix above, there are 33 non-negative circuits from a total of 198 circuits: 5 2-ers, 10 3-ers, 10 4-ers, and 8 5-ers. The valid randomizations we obtained from those circuits are reported in the following table giving the cardinality of the subsets and number r of different choices, classified by the corresponding integer partition. Randomization r 5+5+5 1 5+5+3+2 5 5+3+3+2+2 5 5+2+2+2+2+2 1 4+4+3+2+2 10 4+3+2+2+2+2 5 3+3+3+2+2+2 5 By the properties of the circuits we know that no proper subset is possible in the previous randomization, so for instance we know that no randomization of the form 5+5+3+2 can share two 5-ers with the randomization 5+5+5. However, the 5+5+5 shares a 5-ers with the randomization 5+2+2+2+2+2, as shown in Fig. 3.Fig. 3 Two randomizations for the directed graph on 5 points in Fig. 2: a 5+5+5 randomization (solid lines) and a 5+2+2+2+2+2 randomization sharing a 5-er (dashed lines) Example 7 Our final example exploits the existing structure of the design/model environment to make finding the circuits more straightforward, as we saw for factorial designs. The full saturated X-matrix below is taken from a Haar wavelet model on [-1,1] with depth three from the constant term:X=111010001110-100011-10010011-100-1001-10100101-10100-101-10-100011-10-1000-1. Making use of the intrinsic orthogonality we use columns 2,3,4 for the X1 matrix leaving the last four columns to extract the circuits. Computing the circuit basis for X1 we obtain 16 circuits with 0-1 entries and with support on 4 points. Each vector has a complementary vector (interchanging the ones and zeros) which together form a randomization scheme with 2 randomized blocks, i.e., of the form 4+4. This example is small enough that also a direct computation is possible. As an exercise, we find that the circuits can be computed by brute force solving the equations:xi(1-xi)=0,i=1,…,8x1+x2+x3+x4-x5-x6-x7-x8=0x1+x2-x3-x4=0x5+x6-x7-x8=0 There are 18 solutions. Excluding the null vector and the vector with all entries equal to 1 (full randomization), we obtain the non-trivial solutions, i.e., 16 binary vectors (x1,…,xn) with 4 ones and 4 zeros, which correspond exactly with the 16 circuits computed by 4ti2. We give just one example of valid randomization for this example to save space. Two non-trivial solutions are(1,0,0,1,1,0,0,1),(0,1,1,0,0,1,1,0) which are confirmed be orthogonal to the model columns 2,3,4. They correspond to the randomization{1,4,5,8},{2,3,6,7}. Finally, we briefly discuss the unimodularity assumption. Although unimodularity seems to be a restrictive assumption, a number of models in important applications are defined by a unimodular matrix. For instance the independence model for two-way tables has an unimodular design matrix, the Kronecker product of two unimodular matrices is unimodular, providing a large class of models with unimodular design matrix. Other examples comes from optimization and graph theory, thus for statistical network models. The coefficient matrix of the constraints in the linear programming formulation of the maximum flow problem is unimodular. An example from graph theory has been used in Example 6. There are criteria to check whether a matrix is totally unimodular, but they are rather technical and a detailed analysis in that direction is outside the scope of the present paper. For further details and applications of unimodular matrices the reader can refer to, e.g., Schrijver (2003). Discussion We can ask a skeptical general question: given the wealth of combinatorial theory to find orthogonal blocks what benefit does the circuit method have? An immediate answer is that it provides, in appropriate cases, the choice of a large, even very large, variety of valid randomizations schemes and under special conditions all valid randomizations. Weighing designs give some intuition. Historically there are two types. Weighing a set of objects on a single pan weighing machine is very similar to the choice experiments. A chemical balance experiment has two pans and compares sets of objects. In the chemical balance the observation itself is a difference, that is an empirical contrast, whereas in the single pan case we have to reparametrized creating X1 to obtain contrasts, as in the A/B experiment. Informally, we could say the contrast matrix X1 represents a two-pan experiment embedded in a one pan experiment. It is important to emphasize that the nature of the lattice of circuits in a particular problem depends on the structure of the X1 matrix. Cost considerations and optimality of the experiment may point toward particular randomization schemes. In some cases choice of X1 may mean there is no randomization other that full randomization (over units) of the whole experiment. Conversely, the need to randomize because of perceived sources of bias will restrict the form of X1 as in simple A/B testing. The blocks of a randomization scheme as defined here generalize the idea of a randomized blocked experiment and there is no requirement for equal block size, unless imposed. Stratified sampling is covered if the contrast of interest are within strata. Valid randomizations form a lattice under refinement which we suggest is natural generalization of nested randomization. A single non-decomposable binary vector orthogonal to the X1 matrix is a minimal element. A non-decomposable valid randomization corresponds to partition of N={1,2,…,n}. There may be more than one non-decomposable valid scheme, as we saw in the 23 example in Sect. 4.1 and in Example 7. Also relevant is randomization cost. It may be that a cost function which is related to the structure of the randomization and which is order preserving with respect to the refinement in the lattice could lead to useful strategies in cases where, as we have seen, the choice of valid randomizations is very large. That is, we have in the background the idea that more refined randomization is cheaper. There is a considerable literature on sequential randomization with a model, in the A/B case, that subjects (e.g., patients) are awarded treatments A or B on the equivalent of a toss of a fair coin (there is a considerable work on biased coin design which we do not cover). This is an example where the method in this paper should be a cheaper procedure administratively than randomizing over a fixed population in order to conduct a more complex randomized block experiment. Note that in the 22 experiment of Example 1 with two blocks of size 2, each block only supplies some of the information. The same for the 4 blocks of size 2 in the 23 experiment, whereas for the two 12 fractions of size 4 the parameters can be estimated from each block. In the 2-out-of-4 choice experiments we compare similarly attributes (1, 2) v. (3, 4), (1, 3) v. (2, 4) and (1, 4) v. (2, 3). The two-pan metaphor is useful. The extension to the k-out-of-2k example is straightforward and the blocks arise from all ways of splitting 2k objects into disjoint set of size k. It is likely, in our view, that sequential and adaptive randomization will be increasingly important as costs are traded with effectiveness. Their impressive use in CoViD-19 vaccination trials (e.g., Thorlund et al. 2020; Knoll and Wonodi, 2021) is likely to have a lasting impact. The paper could have been written concentrating on the link to matroid theory, indeed the term circuit is from matroid theory and the circuits presented here form a linear circuit, in the matroid sense. Another mathematical feature is that each block of randomization scheme defined here has an associated permutation group and the full randomization scheme generates a subgroup of the full permutation group Sn. All possible schemes for a particular example may lead to a complex lattice of subgroups under set partition refinement. The relation between matroids and permutation groups has been studied in Cameron and Fon-Der-Flaass (1995). Declarations Conflict of interest The authors declare no conflicts of interest associated with this manuscript. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 4ti2 team. (2018). 4ti2—A software package for algebraic, geometric and combinatorial problems on linear spaces. https://4ti2.github.io. Bailey RA Rowley CA Valid randomization Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences 1987 410 1838 105 124 10.1098/rspa.1987.0030 Box GE Hunter JS Hunter WJ Statistics for experimenters 1978 Wiley Cameron PJ Fon-Der-Flaass D Bases for permutation groups and matroids European Journal of Combinatorics 1995 16 6 537 544 10.1016/0195-6698(95)90035-7 Cox DR Randomization in the design of experiments International Statistical Review 2009 77 3 415 429 10.1111/j.1751-5823.2009.00084.x Das M Jain R On component analysis of factorial and fractional factorial experiments Biometrics 1970 26 4 823 833 10.2307/2528727 Dean A Morris M Stufken J Bingham D Handbook of design and analysis of experiments 2015 Chapman & Hall CRC Press Diaconis P Sturmfels B Algebraic algorithms for sampling from conditional distributions The Annals of Statistics 1998 26 1 363 397 10.1214/aos/1030563990 Drovandi CC Holmes CC McGree JM Mengersen K Richardson S Ryan EG Principles of experimental design for big data analysis Statistical Science 2017 32 3 385 404 10.1214/16-STS604 28883686 Fontana R Rapallo F Wynn HP Circuits for robust designs Statistical Papers 2022 63 5 1537 1560 10.1007/s00362-021-01285-6 Grayson, D. R., Stillman, M. E. (2019). Macaulay2, a software system for research in algebraic geometry. Available at http://www.math.uiuc.edu/Macaulay2/. Guzowski, L., Tatara, E., Milostan, C. (2014). Scoping study using randomized controlled trials to optimize small buildings’ and small portfolios’(SBSP) energy efficiency programs. Technical Report, ANL/DIS-14/8, Argonne National Lab.(ANL), Argonne, IL (United States). Kahle D O’Neill C Sommars J A computer algebra system for R: Macaulay2 and the m2r package Journal of Statistical Software 2020 93 9 1 31 10.18637/jss.v093.i09 Kempthorne O The randomization theory of experimental inference Journal of the American Statistical Association 1955 50 271 946 967 10.2307/2281178 Knoll MD Wonodi C Oxford-AstraZeneca COVID-19 vaccine efficacy The Lancet 2021 397 10269 72 74 10.1016/S2589-7500(20)30086-8 Kohavi R Longbotham R Sammut C Webb GI Online controlled experiments and A/B testing Encyclopedia of machine learning and data mining 2017 Springer 922 929 Pesce E Riccomagno E Wynn HP Greselin F Deldossi L Bagnato L Vichi M Experimental design issues in big data: The question of bias Statistical learning of complex data 2019 Springer 193 201 Pesce E Porro F Riccomagno E Large datasets, bias and model-oriented optimal design of experiments Quality and Reliability Engineering International 2022 10.1002/qre.3165 Schrijver A Combinatorial optimization. Polyhedra and efficiency, algorithms and combinatorics 2003 Springer Scott AJ Smith TMF Minimax designs for sample surveys Biometrika 1975 62 2 353 357 10.2307/2335372 Simões Pereira J On matroids on edge sets of graphs with connected subgraphs as circuits II Discrete Mathematics 1975 12 55 78 10.1016/0012-365X(75)90095-3 Stenger H A minimax approach to randomization and estimation in survey sampling The Annals of Statistics 1979 7 2 395 399 10.1214/aos/1176344622 Stigler SM The use of random allocation for the control of selection bias Biometrika 1969 56 3 553 560 10.2307/2334663 Sturmfels B Gröbner bases and convex polytopes. University lecture series 1996 American Mathematical Society Thorlund K Dron L Park J Hsu G Forrest JI Mills EJ A real-time dashboard of clinical trials for COVID-19 The Lancet Digital Health 2020 2 6 E286 E287 10.1016/S2589-7500(20)30086-8 32363333 Wynn HP Minimax purposive survey sampling design Journal of the American Statistical Association 1977 72 359 655 657 10.2307/2286234
PMC009xxxxxx/PMC9789301.txt	==== Front Soc Psychiatry Psychiatr Epidemiol Soc Psychiatry Psychiatr Epidemiol Social Psychiatry and Psychiatric Epidemiology 0933-7954 1433-9285 Springer Berlin Heidelberg Berlin/Heidelberg 36564584 2404 10.1007/s00127-022-02404-w Original Paper Technology-based communication among Hurricane Maria survivors in the United States: a trans-territorial lens http://orcid.org/0000-0001-7057-8316 Pineros-Leano M. [email protected] 1 Salas-Wright C. P. 1 Maldonado-Molina M. M. 2 Hodges J. C. 1 Brown E. C. 3 Bates M. M. 2 Mendez-Campos B. 1 Rodríguez J. 4 Schwartz S. J. 5 1 grid.208226.c 0000 0004 0444 7053 Boston College, School of Social Work, Chestnut Hill, MA USA 2 grid.15276.37 0000 0004 1936 8091 University of Florida, Gainesville, FL USA 3 grid.26790.3a 0000 0004 1936 8606 Department of Public Health Sciences, University of Miami, Miller School of Medicine, Miami, FL USA 4 Iglesia Episcopal Jesús de Nazaret, Orlando, FL USA 5 grid.89336.37 0000 0004 1936 9924 University of Texas at Austin, Austin, TX USA 24 12 2022 2023 58 7 10751085 1 4 2022 12 12 2022 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany 2022. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Purpose Rooted in a trans-territorial framework, the present study was designed to provide new evidence regarding the patterns of communication among Hurricane Maria survivors who migrated to the U.S. in the aftermath of the storm. Methods A total of 319 Hurricane Maria survivor adults ages 18 and older were recruited into the Adelante Boricua study between August 2020 and October 2021. Most participants had relocated to the U.S. between 2017 and 2018. We used latent profile analysis and multinomial regression to examine the relationship of technology-based communication with depressive symptoms, well-being, cultural connection, and migration stress. Results We identified a five-class solution, consisting of (1) moderate communication (32%), (2) disengaged (24%), (3) no social media (18%), (4) daily with family in Puerto Rico (6%), and (5) daily trans-territorial (13%) typologies. Participants in the disengaged class were more likely to report elevated depressive symptoms and limited English proficiency, lower prosocial behaviors, lower levels of religiosity, lower attendance at religious services in the U.S., and less engagement in social activities, compared to participants in the Moderate Communication class. Conclusion Roughly one in four individuals in our sample reported very limited technology-based communication with friends/family in their sending and new-receiving communities. As technology and smartphones continue to become integrated into 21st-century life, it is vital that researchers explore how the tremendous potential for connectedness relates to trans-territorial crisis migrants’ well-being and adaptation. Keywords Hurricane Maria Puerto Rican migrants Communication Depressive symptoms http://dx.doi.org/10.13039/100006545 National Institute on Minority Health and Health Disparities MD014694 MD014694-03S1 MD014694 MD014694 Pineros-Leano M. Salas-Wright C. P. Maldonado-Molina M. M. Schwartz S. J. issue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction In September 2017, Hurricane Maria made landfall in Puerto Rico creating widespread damage in what was the third costliest hurricane in United States (U.S.) history [1]. In the storm’s aftermath, several hundred thousand Puerto Ricans—many of whom were left without access to food, water, electricity, or adequate housing for weeks or even months—fled to Central Florida and elsewhere on the U.S. mainland [2]. Maria survivors on the U.S. mainland only received temporary shelter through the Temporary Sheltering Program. Besides this program, no other federal supports were offered to aid survivors with the resettlement process [3]. Several years later, tens of thousands of “Maria survivors” remain in the U.S. [2]. Frontline journalism and broad surveillance efforts have provided important information about displaced Puerto Ricans; nevertheless, several questions remain as to the longer-term experiences of migration, adaptation, and health among this population. One pressing question is the degree to which Maria survivors who migrated to the U.S. have integrated into their new-receiving communities while maintaining connections with friends and family in Puerto Rico. It has been observed that the construct of “trans-territorial” connectedness is particularly salient for Puerto Ricans given their status as U.S. citizens, which allows for relatively easy back-and-forth movement between the island and the mainland [4, 5]. Critically, 21st-century technological developments have opened new possibilities for such connectedness as the omnipresence of sophisticated smartphones makes regular voice, text, and social media communication a possibility for many [6]. Whereas migration previously disrupted communication with important people in one’s home country, today it is possible for migrants to be in daily contact with people back home. Research on the Latin American migrant population has increasingly explored the construct of trans-nationalism (or trans-territorialism, to coin a phrase for Puerto Ricans) [7–10]. Trans-territorialism refers to myriad ways in which migrants maintain connection with individuals, traditions, and social activities both in their place of origin and their new-receiving context. Although the transnational/territorial migration literature is now quite robust and rapidly expanding, relatively little work has examined the ways in which technology-based communication facilitates such connections, particularly among Puerto Rican migrants [9, 10]. Furthermore, the few studies that have been conducted in this area suggest mixed findings [9]. A study investigating the impact of trans-nationalism/territorialism on immigrants’ and migrants’ wellbeing [9], found that maintaining some linkages with the place of origin was associated with higher levels of wellbeing. That study also found that having frequent transnational communication was associated with lower levels of wellbeing; however, this association was no longer significant after controlling for English fluency, gender, education and income, indicating the complexity of transnational/trans-territorial communication [9]. Other literature [8, 11] has found transnational/trans-territorial communication to be an essential part of building and maintaining ties with family members in the place of origin and of improving mental health and overall wellbeing. A study [8] found that transnational communication with family members can protect people from social isolation and enhance emotional support among (im) migrants, indicating the importance of maintaining strong ties with family in the place of origin. This literature suggests not only that it is necessary to understand whether people communicate with family members and friends in the place of origin, but also that it is imperative to assess the frequency of communication. Given the complexity of transnational/trans-territorial communication, there is a need to explore the ways in which migrants use phone/internet technology to facilitate trans-territorial connectivity and, in turn, to understand what the degree of connectedness may mean in terms of migrant adaptation and wellbeing. Studying a population of Venezuelan adolescents, Salas–Wright, Vaughn, et al. [12] examined the dynamics of technology-based communication with friends in both the U.S. and Venezuela. Using a person-centered approach, they identified subtypes of Venezuelan youth. These subtypes were characterized by substantial heterogeneity, with some youth reporting daily transnational communication, others reporting more frequent communication with friends in the U.S. than in Venezuela, and others who were relatively disconnected from friends in their new-receiving society and back home. Although that study shed new light on technology-based communication and its role in facilitating transnational dynamics, it was limited by several shortcomings, including its focus on young adolescents (who may have varying levels of access to phones/internet) and its singular focus on friends (which excluded critical family relationships). Rooted in a trans-territorial framework and building upon recent work examining technology-based communication among Latin American migrants, the present study was designed to provide new and exploratory evidence as to the patterns of communication among Maria survivors in the U.S. Specifically, we use a person-centered approach to model the subtypes of trans-territorial communication with friends and family in both the U.S. and Puerto Rico among a population of recently arrived Puerto Rican migrants. Our study not only has the potential to shed new light on the experiences of displaced Puerto Ricans, but it was also designed to advance our understanding of the ways in which today’s migrants build connections and stay connected back home. Methods Sample and procedures A total of 319 Maria survivor adults ages 18 and older were recruited into the Adelante Boricua study between August 2020 and October 2021. To be part of the study, potential participants had to fulfill the following criteria: (1) be a Hurricane Maria survivor currently living in the U.S. mainland, (2) be at least 18 years old at the time of enrollment, and (3) have no plans of moving back to Puerto Rico for at least the next 6 months. This last criterion was included to be able to follow participants over a long period of time to better understand their resettlement experience; however, in practice, no interested individuals were excluded on the basis of this criterion. We used a respondent-driven sampling approach to recruit participants, which consisted of community partner agencies referring initial—or “seed”—participants who, in turn, referred other participants [13]. Our primary community partner in Central Florida is a religious community that provides social services and supports to an array of recently arrived (im)migrant populations. Community partners elsewhere included a local chamber of commerce, Puerto Rican community groups, and immigrant aid organizations. Recruitment took place via our partner organization’s connections in Central Florida and via promotion on radio, television, and social media. We conducted community-engaged research where our community partners and community advisory boards provided input at every stage of the survey design, including the identification of relevant constructs and the evaluation of the linguistic and cultural appropriateness of items. The survey took approximately 60 min to complete, and it included topics related to demographics, migration-related cultural stress, acculturation, prosocial behavior, religiosity, and behavioral health outcomes. Participants who completed the survey received a $100 incentive and were eligible for secondary incentives for referring eligible individuals who joined the study ($30 per successful referral, up to five referrals). Bilingual study staff members were available to help participants access the online survey whenever participants requested support. Because of the COVID-19 pandemic, all data were collected online using Qualtrics survey software. English and Spanish versions of the survey were pretested and made available; however, all Adelante Boricua participants (included in this manuscript) elected to complete the survey in Spanish. Measures All measures described below were translated and back translated by bilingual Spanish speakers familiar with the nuances of Puerto Rican Spanish and, subsequently, examined in cognitive interviews conducted with Puerto Rican individuals residing in the U.S. and in Puerto Rico. Any items that prompted confusion were carefully examined in conversation with our community partners and community advisory board comprised of leaders within the Puerto Rican migrant communities in Central and South Florida. Trans-territorial communication As shown in Table 1, we used 12 items to measure communication with family and friends in the U.S. and Puerto Rico. These items built upon the work of Salas–Wright, Vaughn, et al. [12] who previously adapted items from the Health Behavior of School-Age Children questionnaire [14, 15]. Three core questions were repeated with respect to four reference groups: friends in the U.S., family in the U.S., friends in Puerto Rico, and family in Puerto Rico. Specifically, participants were asked “How often do you communicate with [friends/family] in [the U.S./Puerto Rico] via” phone/voice (e.g., FaceTime or WhatsApp), text/chat (e.g., WhatsApp or Facebook Messenger), and social media (e.g., Instagram or Snapchat). Response options for each question included “almost never/never” (1), “less than weekly” (2), “weekly” (3) and “daily” (4).Table 1 Self-reported trans-territorial communication Never or almost never Less than weekly Weekly Every day [Casi nunca o nunca] [Menos de una vez a la semana] [Semanalmente] [Todos los días] % % % % United States How often do you communicate with friends in the United States via [¿Qué tan frecuente usted contacta a sus amistades que viven en los Estados Unidos por?] Phone/voice [Teléfono o video llamadas] 21.9 24.5 37.8 15.9 Text message/chat [Mensajes de text o chat] 13.8 22.2 36.9 27.2 Social media [Redes sociales] 33.2 18.8 29.2 18.8 How often do you communicate with family in the United States via [¿Qué tan frecuente usted contacta a sus familiares que viven en los Estados Unidos por?] Phone/voice 16.9 25.2 35.9 22.1 Text message/chat 14.9 22.2 37.5 25.4 Social media 35.3 17.1 29.7 17.8 Puerto Rico How often do you communicate with friends in Puerto Rico via [¿Qué tan frecuente usted contacta a sus amistades que viven en Puerto Rico por?] Phone/voice 17.3 26.6 35.9 20.2 Text message/chat 12.8 26.8 39.5 20.9 Social media 30.8 22.3 30.8 16.1 How often do you communicate with family in the Puerto Rico via [¿Qué tan frecuente usted contacta a sus familiares que viven en Puerto Rico por?] Phone/voice 9.4 17.1 40.0 33.6 Text message/chat 10.1 16.0 37.3 36.6 Social media 32.9 15.1 27.3 24.7 Depressive symptoms We used the Boston form of the Centers for Epidemiologic Studies Depression Scale [16]. This measure tapped into depressive symptoms, such as listlessness, anhedonia, and lack of interest in activities, during the week prior to assessment. Sample items included “I felt depressed” and “I felt like everything I did required a lot of effort” with response options including “rarely or never” (1), “sometimes” (2), “often” (3), and “almost always” (4). We examined internal consistency with all 10 items and observed that the two positive items (“I was happy” and “I enjoyed life”) had item-rest correlations of 0.05 and − 0.04, and standardized loadings of 0.17 and − 0.06, whereas all other items had correlations in the range of 0.59–0.82. Based on these very low item-total correlation values, we removed these two items. Our finding with regard to these reverse-keyed items is similar to observations made by other researchers working with minority or international samples [17]. Notably, these two items were the only two positively phrased items in the Boston form of the CES-D. Prior validation work indicated that switching between positively and negatively phrased items can result in confusion and, ultimately, poor psychometric performance, especially in populations with lower overall levels of formal education [18]. Cross-cultural research using the CESD-10 has also found that the two positively phrased items perform differently than the remainder of the items, and have cautioned researchers to carefully consider their appropriateness [17]. Using the resulting 8-item version, Cronbach’s alpha was 0.89 in the present sample. Wellness and strengths Three measures were examined in the domain of wellness and strengths: prosocial behavior, intrinsic religiosity, and religious service attendance. Prosocial behavior Prosocial behavior (α = 0.90) was measured using an adapted version of the Prosocial Tendencies Measure-Revised [19]. To reduce respondent burden, we used only the Dire (4 items) and Emotional (4 items) subscales from the Prosocial Tendencies Measure [20]. This measure included self-reported behaviors in various domains (e.g., public, anonymous, altruistic) and has been used widely with Latin American populations [21, 22]. Sample items include “I tend to help people who are in a real crisis or need” or “when people ask me to help them, I don’t hesitate” with response options ranging from “does not describe me at all” (1) to “describes me greatly” (5). Intrinsic religiosity and religious service attendance Intrinsic religiosity (α = 0.89) was self-assessed using the Santa Clara Strength of Religious Faith Questionnaire: brief form, a multicultural assessment tool consisting of 5 items [23]. Sample items include “I pray daily,” and “I look to my faith as a source of inspiration” with response options including “strongly disagree” (1), “disagree” (2), “agree” (3), and “strongly agree” (4). We also examined religious service attendance using the following prompt: “During the past 12 months, how many times did you attend religious services? Please do not include special occasions, such as weddings, funerals, or other special events in your answer.” Response options included “never” (1), “sometimes/two or three times per year” (2), “monthly” (3), “several times monthly” (4), and “weekly or more” (5). This item was adapted from a commonly used measure included in the National Survey on Drug Use and Health (see [24, 25]). Cultural connection Three measures were examined in the domains of cultural connection: involvement in U.S activities, involvement in Puerto Rican/Latin American activities, and the degree to which individuals miss living in Puerto Rico. U.S./Puerto Rican activities An adapted version of the Bicultural Involvement Questionnaire (BIQ; [26]) was used to measure involvement in U.S./Puerto Rican Activities. The BIQ consists of two subscales: the U.S. subscale (α = 0.92) measured affinity for U.S. social behaviors (e.g., music, television, venues), and the Puerto Rican subscale (α = 0.93) measured affinity with Puerto Rican/Latino social behaviors—in the present study, we refer to the former as “U.S. activities” and the latter as “Puerto Rican activities.” For both subscales, response options ranged from “not at all” (1) to “very much” (5). Miss living in Puerto Rico A single item was used to measure the degree to which respondents missed life on the island: “How much do you miss living in Puerto Rico?” Response options included “I don’t miss it at all” (1), “I miss it sometimes” (2), “neutral” (3), “I miss it” (4), and “I miss it a lot” (5). This straightforward item was developed based on feedback from our community partners and community advisory board. Migration stress Consistent with cultural stress theorizing (see [27, 28]), migration stress was measured via three constructs: negative context of reception, discrimination, and limited English proficiency. Negative context of reception We measured negative context of reception (α = 0.84) using the 6-item Negative Context of Reception Scale [29]. Negative context of reception examines the degree to which migrants perceive that their group is unwelcome or mistreated on the basis of its cultural or national identity [29, 30]. Sample items include “People from Puerto Rico are not welcome here” and “People from this country regularly criticize Puerto Ricans.” Participants responded to each item using a 5-point scale ranging from “strongly disagree” (1) to “strongly agree” (5). Discrimination We measured discrimination using Phinney, Madden, and Santos’s [31] seven-item self-reported discrimination instrument (α = 0.95). This measure assessed the frequency of being treated negatively by employers or not being accepted due to the person’s national origin or ethnicity. Sample items include: “How often do employers treat you unfairly or negatively because you are Puerto Rican?” and “How often do other people (such as police and shopkeepers) treat you unfairly or negatively?” Participants responded to each item using a 5-point scale ranging from “not at all” (1) to “almost every day” (5). Notably, negative context of reception and discrimination are distinct constructs as the former identifies general perceptions around one’s group whereas the latter captures direct experiences of identity-based mistreatment. Limited English proficiency We assessed limited English proficiency using one question: “How well do you speak English?” Response options include “very little” (1), “little” (2), “well” (3), and “very well” (4). Response options were reverse coded to emphasize the language-related challenges experienced by many Maria survivors. Demographic factors Participant age (continuous), gender (male = 0, female = 1), and year of arrival in the U.S. (2017–2020) were included as indicator covariates in the latent modeling and control variables in the multinomial regression analysis. Data analysis Data were analyzed using a three-step approach. First, we identified a sequence of latent profile models ranging from one to seven classes using Latent GOLD® 5.1 software [32]. The twelve trans-territorial variables (i.e., how often do you communicate with (a) friends in the U.S. via phone/voice, text/chat, and/or social media; (b) family in the U.S. via phone/voice, text/chat, and/or social media; (c) friends in Puerto Rico via phone/voice, text/chat, and/or social media; and (d) family in Puerto Rico via phone/voice, text/chat, and/or social media) were specified as indicator variables with demographic variables specified as indicator covariates. Then, we used five statistical criteria to identify the best fitting model: the Bayesian Information Criterion (BIC), Akaike Information Criterion (AIC), Consistent Akaike Information Criterion (CAIC), log likelihood (LL), and entropy. All things being equal, lower BIC, AIC, and CAIC values and higher LL values reflect better model fit. Higher entropy values—approaching 1.00—indicate clear class delineation [33]. Latent Gold does not provide a likelihood ratio test, so this was not included as a factor in determining the number of classes for the final solution. When selecting the best fitting model, analysts should also consider parsimony (preferring solutions with fewer classes unless additional classes provide increased explanatory value) and the substantive interpretability of the solution. After modeling the latent classes, multinomial regression was conducted—with the nominal class solution specified as the dependent variable—using Stata 16 SE to examine key correlates of class membership while controlling for demographic factors. Results Participants in the present study were 319 adult Hurricane Maria survivors (71% women, M = 38.7 years, SD = 12.1 years, range 18–77, 80% under age 50) residing on the U.S. mainland. In terms of year of arrival, 59.3% of participants arrived on the U.S. mainland in 2017, 29.2% in 2018, 6.3% in 2019, and 3.8% in 2020. Most participants in this study (75.3%) were living in Central Florida at the time of data collection, with Orlando (41.9%) and Kissimmee (20.8%) being the areas where most Hurricane Maria survivors resided. Participants were also referred or recruited from Texas (6.3%), the New England states (3.8%), Illinois (3.2%), Delaware (1.9%), South Carolina (1.9%), and other U.S. locations (7.6%). Latent classes The latent class analysis indicated that a five-class solution was the best fitting model (see Table 2). A four-class solution was a possibility in terms of statistical criteria; however, the four-class solution omitted a conceptually coherent and distinct class (see Class # 4 below), and the fit statistics for the five-class solution were acceptable. The conceptual fit of the latent profile models was examined by plotting the mean values for the twelve communication variables by each of the latent classes (see Fig. 1). Using the five-class solution, chi2 tests for contingency tables with the five classes and each indicator variable (e.g., phone: friend, US) were significant at p < 0.001 for all of the indicator variables. We provided descriptive names for each of the classes based upon our interpretation of the “shape” of each class. A description and explanation of the five classes follows here:Table 2 Fit indices for latent classes # Class solution Log likelihood/LL Bayesian information criterion/BIC Akaike’s information criterion/AIC Consistent Akaike’s information criterion/CAIC Entropy R2 1-Class − 4785.87 9779.29 9643.75 9815.30 – 2-Class − 4252.94 8799.90 8607.88 8850.90 0.90 3-Class − 4058.75 8498.01 8249.51 8564.01 0.89 4-Class − 3906.42 8279.82 7974.84 8360.82 0.92 5-Class − 3836.86 8227.18 7865.72 8323.18 0.92 6-Class − 3788.16 8216.26 7798.32 8327.26 0.91 7-Class − 3727.66 8181.73 7707.31 8307.73 0.89 Fig. 1 Patterns of phone, text, and social media communication, by latent class Class # 1: moderate communication This class comprised 32% of the sample and was characterized by engaging with friends and family in the U.S. and Puerto Rico slightly less than weekly via phone call, text message, and social media. Class # 2: disengaged This class comprised 24% of the sample. The Disengaged class was characterized by low levels of engagement with family and friends either in the U.S. or Puerto Rico via phone call, text message, or social media. Participants in this class were slightly more likely to engage with family members in the U.S. and Puerto Rico, compared to engagement with friends. Class #3: no social media This class comprised 18% of the sample and it was characterized by slightly less than weekly levels of engagement with family and friends in the U.S. and with friends in Puerto Rico via phone and text. A particular feature of participants in this class is that they were entirely unengaged in social media. Class # 4: daily with family in Puerto Rico This class comprised 6% of the sample and it was characterized by having slightly less than weekly contact with family and friends in the U.S. and with friends in Puerto Rico via phone call, text message, and social media. What makes this class different than others is that this class also was characterized by having daily contact with family members in Puerto Rico through phone calls, text messages, and social media. Class # 5: daily trans-territorial This class was made up by 13% of the sample and was characterized by close to daily levels of engagement with family and friends in the U.S. and in Puerto Rico through phone calls, text messages, and social media. Demographic characteristics of classes Compared to participants in Class #1 (Moderate Communication), which was used as the reference class, members of the Disconnected class were more likely to be older (M = 41.5, SD = 13.3, RR = 1.04 [95% CI 1.01–1.06]) and more likely to have moved to the U.S. shortly after Hurricane Maria (RR = 1.61 [95% CI 1.01–2.58]). Members of Classes # 3 (No Social Media; 83.6%; RR = 2.94 [95% CI 1.23–7.05]) and # 4 (Daily with Family in Puerto Rico; 86.7%; RR = 3.72 [95% CI 1.41–9.77]) were significantly more likely to be female. Supplemental t tests revealed that—for the full sample—no differences were observed in terms of social media utilization between male and female respondents. No other demographic differences emerged between classes. Psychosocial characteristics of the trans-territorial communication classes Table 3 displays the intrapersonal and contextual characteristics of participants in Classes #2–5 as compared to participants in Class # 1, which was used as the reference class. Participants in the Disconnected class were more likely to have reported higher levels of depressive symptoms (RR = 1.67 [95% CI 1.06–2.64]), compared to participants who maintained moderate levels of communication with their families and friends in the U.S. and Puerto Rico. Participants in the Disconnected class also were less likely to engage in prosocial behaviors (RR = 0.55; [95% CI 0.37–0.83]), to report lower levels of religiosity (RR = 0.50; [95% CI 0.32–0.77]), and less likely to attend religious services in the U.S. (RR = 0.73; [95% CI 0.58–0.93]), compared to participants in the Moderate Communication class. We also found that participants in the Disconnected class were less likely to enjoy American (RR = 0.55; [95% CI 0.39–0.77]) and Puerto Rican (RR = 0.67; [95% CI 0.46–0.97]) activities, and less likely to report missing living in Puerto Rico (RR = 0.79; [95% CI 0.63–0.99]), compared to participants in the Moderate Communication class. Finally, participants in the Disconnected class were more likely to report limited English proficiency (RR = 1.71; [95% CI 1.25–2.35]) compared to participants in the Moderate Communication class.Table 3 Intrapersonal and contextual characteristics of latent classes #1: Moderate communication (n = 103; 32%) #2: Disconnected (n = 76; 24%) #3: Moderate, no social media (n = 55; 18%) #4: Daily w/family in Puerto Rico (n = 45; 6%) #5: Daily transterritorial (n = 40; 13%) M (SD) M (SD) RR 95% CI M (SD) RR 95% CI M (SD) RR 95% CI M (SD) RR 95% CI Depression CESD mean 1.68 (0.6) 1.91 (0.7) 1.67 1.06–2.64 1.82 (0.7) 1.39 0.83–2.33 1.74 (0.5) 1.14 0.65–2.00 1.54 (0.6) 0.68 0.36–1.29 Wellness/strengths Prosocial 4.06 (4.1) 3.71 (0.8) 0.55 0.37–0.83 4.12 (0.6) 1.03 0.63–1.66 4.18 (0.7) 1.10 0.64–1.88 4.27 (0.7) 1.60 0.91–2.82 Religiosity 3.23 (0.7) 2.97 (0.8) 0.50 0.32–0.77 3.19 (0.8) 0.72 0.43–1.18 3.13 (0.7) 0.69 0.40–1.17 3.28 (0.8) 1.09 0.63–1.89 Religious services 2.56 (1.38) 2.11 (1.33) 0.73 0.58–0.93 2.53 (1.56) 0.91 0.71–1.15 2.44 (1.44) 0.90 0.69–1.17 2.73 (1.4) 1.10 0.85–1.43 Cultural connection US Activities 3.53 (1.0) 2.95 (0.9) 0.55 0.39–0.77 3.20 (0.8) 0.74 0.52–1.05 3.09 (1.1) 0.63 0.43–0.93 3.81 (1.1) 1.34 0.91–1.97 PR activities 4.36 (0.7) 4.12 (0.9) 0.67 0.46–0.97 4.16 (0.9) 0.65 0.43–0.98 4.34 (0.9) 0.83 0.52–1.33 4.59 (0.6) 1.64 0.92–2.92 Miss living in PR 3.97 (1.3) 3.60 (1.3) 0.79 0.63–0.99 3.51 (1.3) 0.77 0.60–0.99 3.95 (1.4) 1.02 0.77–1.35 4.3 (1.1) 1.24 0.89–1.72 Migration stress Negative context 2.51 (0.7) 2.62 (0.8) 1.12 0.76–1.65 2.31 (0.7) 0.69 0.45–1.05 2.40 (0.8) 0.82 0.52–1.29 2.24 (0.9) 0.64 0.40–1.02 Discrimination 2.27 (0.9) 2.34 (1.0) 1.04 0.75–1.43 2.07 (0.9) 0.75 0.52–1.09 1.98 (0.8) 0.69 0.46–1.04 1.76 (0.8) 0.50 0.31–0.79 Limited english 2.54 (1.0) 3.14 (0.9) 1.71 1.25–2.35 2.76 (1.0) 1.12 0.81–1.56 2.69 (1.0) 1.11 0.78–1.57 2.65 (1.1) 1.08 0.76–1.55 Class # 1 is reference class M mean value for latent class, SD standard deviation, % proportion of latent class, RR risk ratio, CI confidence interval Participants in the No Social Media class were less likely to enjoy Puerto Rican activities (RR = 0.65; [95% CI 0.43–0.98]) or to miss living in Puerto Rico (RR = 0.77; [95% CI 0.60–0.99]), compared to participants in the Moderate Communication class. Participants with daily communication with family in Puerto Rico were less likely to enjoy American activities (RR = 0.63; [95% CI 0.43–0.93]), compared to participants in the Moderate Communication class. Finally, participants in the Daily Trans-Territorial class were less likely to perceive discrimination (RR = 0.50; [95% CI 0.31–0.79]). Discussion The present study provides new evidence as to how Puerto Rican Hurricane Maria survivors develop and maintain—to various degrees and in various configurations—technology-based connections with friends and family in their new-receiving context and in Puerto Rico. Critically, findings also shed new light on how such communication intersects with wellness, cultural connectedness, migration stress, and mental health. The first key finding is the identification of five distinct subtypes of Puerto Rican migrants on the basis of trans-territorial communication. Simply, we did not see an ordinal layering of trans-territorial communication variables (e.g., low, medium, high), but rather the person-centered analysis suggests that substantively distinct configurations of communication exist. For instance, we found that roughly one-third (32%) of our sample maintains “Moderate Communication” (slightly less than weekly, on average) with friends and family in the U.S. and in Puerto Rico via phone, text, and social media. We also identified subgroups defined by no engagement on social media (18%), daily contact with family in Puerto Rico (6%), and daily trans-territorial contact with friends and family in the U.S. and in Puerto Rico (13%). Beyond the modeling of heterogeneity in general, the second key finding is that nearly one-quarter (24%) of our sample was classified as “Disconnected.” Members of this class reported infrequent communication with friends/family in the U.S. and, to a slightly lesser degree, with loved ones in Puerto Rico. In simple terms, these individuals—who we found to be somewhat older (25% were age 50 +) and migrated almost exclusively in 2017 or 2018 (97%)—are quite isolated in terms of technology-based communication. Close inspection revealed that this “Disconnected” group is distinct from the rest of our sample in several important ways. They are less likely to report prosocial behavior, less likely to be religious or attend religious services, and are less likely to enjoy activities (music, entertainment, social events) that are rooted in Puerto Rican or U.S. culture. We also found that members of this “Disconnected” group were more likely to report limited English language ability yet—somewhat paradoxically—less likely to miss living in Puerto Rico. This relatively large group seemed to be disconnected not only from technology-based communication, but also from other key social and cultural aspects of life. It is perhaps unsurprising that rates of depressive symptoms were especially elevated among this profoundly isolated subgroup. Although we are unable to draw further conclusions based on our data, one possibility for the level of disengagement of this class may be a function of their relatively elevated median age as well the fact that members of this class migrated shortly after the hurricane, which may suggest that a health condition and the need for stateside medical care may have been an important driver. Future studies should try to better understand the social support, employment status, and service access among Hurricane Maria survivors (as well as survivors of other natural disasters) to better understand the characteristics of this disconnected group. Other noteworthy findings relate to characteristics of the other latent subtypes. For instance, we found that members of the “Daily Trans-Territorial” class were substantially less likely to report having experienced discrimination. Although our data do not allow us to determine why this is the case, several possibilities exist. For one, it is possible that members of this class are outside of the workforce and therefore less exposed to discrimination. Alternatively, it may be that members of this class are especially open to frequently engage with friends and family in the U.S. because they have experienced less discrimination. Another noteworthy finding—which is arguably more straightforward to interpret—is that members of the “Daily with Family in Puerto Rico” class are less likely to enjoy engagement in U.S.-style social activities. This finding seems consistent with a class defined by close/daily connection with family back home in Puerto Rico. In other words, it may be that members of this class remain especially connected with key people and practices that reflect the rich cultural heritage of the island. A final important finding is that there were no differences on depression, wellness, or migration stress between the moderate communication and no social media classes, suggesting that perhaps the level of communication that people have with their families and friends is what is important, regardless of the method of communication. Implications for practice and research Findings have several implications for practice. One is that mental health clinicians and other helping professionals tasked with supporting migrant populations would do well to be mindful to assess technology-based trans-territorial communication [11]. This objective is perhaps most important in terms of identifying individuals who are disconnected from the post-migration context and may be at risk of experiencing mental health problems. Among individuals who appear to be disconnected, it may make sense to explore options for developing connections with others in their new-receiving context or finding ways that such individuals can benefit from the positive elements of social engagement. For instance, given that members who appear to be disconnected also reported limited English language ability, promoting English learning courses could help to decrease their isolation levels. State and local governments can also promote the engagement and resettlement process of Hurricane Maria survivors by providing job development trainings, as well as increased access to health and mental health care. Moreover, it is important to identify ways that disconnected participants can be reached, particularly by health, mental health providers, and community organizations. In terms of implications for research, this last point also speaks to the need for future research to understand the dynamics involved in trans-territorial communication. Among individuals who are most disconnected, there is a need to understand what is driving this disconnection. Are disconnected individuals temperamentally predisposed to isolation? Do they struggle with technology or lack the resources (e.g., a smartphone or tablet) that can facilitate such communication? Do they have strained relationships with friends and family in Puerto Rico? Do they have different traumatic experiences from the hurricane that are making it more difficult to socialize? Do they have more physical health issues that may make it more difficult to socialize? Although we are not able to explore these questions in the present study, qualitative research has the potential to provide the richness and texture necessary to address such questions. Mixed methods research with individuals in other classes—such as the Daily Trans-Territorial and Daily with Family in Puerto Rico classes—would also help us to understand not only the frequency of communication, but the quality and nature of how people interact via phone, text, and social media. Study limitations Findings from the present study should be interpreted in light of several limitations. First, our sample is limited to Puerto Ricans who migrated to the U.S. mainland after Hurricane Maria; therefore, their experiences are not representative of the larger Puerto Rican population. Second, the use of a cross-sectional design indicates that causal relationships cannot be established—for example, limited communication could lead to higher depressive symptoms, or depressed individuals may communicate less with their social networks. Third, we measured structural aspects of communication (i.e., frequency), but we did not assess the content of this communication and do not have information on the nature or quality of the communication. The associations between trans-territorial communication and psychosocial outcomes may depend on the content of what is being communicated as well as on the frequency of contact. Fourth, lack of data on employment status, social support, and physical health pre- and post-migration limits our ability to draw conclusions about what may be impacting or driving levels of communication with family and friends in the U.S. and in Puerto Rico. Finally, the present study was conducted during the context of the COVID-19 pandemic, and public health guidelines and social distancing may have impacted people’s communication habits and their psychosocial functioning. Conclusion Several years after Hurricane Maria upended the lives of countless Puerto Ricans, our findings provide new insight into the experiences and adaptation of Maria survivors who relocated to the U.S. In particular, person-centered analysis revealed substantial variation in terms of how members of this displaced population communicate with friends and family, both in their new-receiving context and back home in Puerto Rico. Of particular relevance, we found that roughly one in four individuals in our sample reported very limited technology-based communication with friends/family in their sending and new-receiving communities. Members of this class were at elevated risk of experiencing depressive symptoms and tended to experience isolation across the domains of wellness/strengths and cultural connection. As technology and smartphones continue to become integrated into 21st-century life, it is vital that researchers explore how the tremendous potential for connectedness relates to the well-being and adaptation of migrants. Acknowledgements We would like to thank our community partners and Community Advisory Boards who have been essential to the development of the study. Author contributions All authors contributed to the study conception and design. Data analyses were performed by CPS-W. The first draft of the manuscript was written by MP-L and CS-W and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript. Funding This work was supported by the National Institute on Minority Health and Health Disparities [NIMHD; Award Numbers R01MD014694, R01MD014694-03S1, F31MD017465] and the National Institute on Alcohol Abuse and Alcoholism [NIAAA; Award Number K01AA026645] of the National Institutes of Health. The content is solely the responsibility of the authors and does not necessarily represent the official views of NIMHD, NIAAA, or the NIH. Data availability The data that support the findings of this study are available upon reasonable request from the corresponding [MPL], second [CPSW], or senior authors [SJS]. Declarations Conflict of interest The authors have no competing interests to declare that are relevant to the content of this article. Ethical approval All study procedures were performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments and were approved by the Institutional Review Board at the University of Miami (Ethics approval number: IRB0053570). Consent to participate Before initiating the survey, all participants consented to be part of the study. ==== Refs References 1. Fischbach JR May LW Whipkey K After Hurricane Maria: predisaster conditions, hurricane damage, and recovery needs in Puerto Rico 2020 Santa Monica RAND Corporation 2. Schachter J, Bruce A (2020) In: The United States Census Bureau (ed). Estimating Puerto Rico's Population After Hurricane Maria: Revising methods to better reflect the impact of disaster. The United States Census Bureau, Suitland 3. Severino K Figueroa DI Hinojosa J Puerto rico one year after Hurricane Maria Centro 2018 New York Center for Puerto Rican Studies 4. Aranda E Rivera FI Puerto Rican Families in Central Florida: prejudice, discrimination, and their implications for successful intergration Women Gender Families Color 2016 4 1 57 85 10.5406/womgenfamcol.4.1.0057 5. Duany J Mobile livelihoods: the sociocultural practices of circular migrants between Puerto Rico and the United States1 Int Migr Rev 2002 36 2 355 388 10.1111/j.1747-7379.2002.tb00085.x 6. Center PR (2021) Mobile fact sheet. Pew Research Center. https://www.pewresearch.org/internet/fact-sheet/mobile/ 7. Alcántara C Chen C-N Alegría M Transnational ties and past-year major depressive episodes among Latino immigrants Cultur Divers Ethnic Minor Psychol 2015 21 3 486 495 10.1037/a0037540 25090146 8. Gonzalez C Katz VS Transnational family communication as a driver of technology adoption Int J Commun 2016 10 21 9. Vaquera E Aranda E The multiple dimensions of transnationalism: examining their relevance to immigrants’ subjective well-being J Soc Res Policy 2011 2 2 47 10. Duany J The orlando ricans: overlapping identity discourses among middle-class Puerto Rican immigrants Cent J 2010 22 1 85 115 11. Bacigalupe G Cámara M Transnational families and social technologies: reassessing immigration psychology J Ethn Migr Stud 2012 38 9 1425 1438 10.1080/1369183X.2012.698211 12. Salas-Wright CP Vaughn MG Goings TC Toward a typology of transnational communication among Venezuelan immigrant youth: implications for behavioral health J Immigr Minority Health 2021 23 5 1045 1052 10.1007/s10903-020-01099-y 13. Heckathorn DD Respondent-driven sampling II: deriving valid population estimates from chain-referral samples of hidden populations Soc Probl 2002 49 1 11 34 10.1525/sp.2002.49.1.11 14. De Looze M van Dorsselaer S Stevens GWJM The decline in adolescent substance use across Europe and North America in the early twenty-first century: a result of the digital revolution? Int J Public Health 2019 64 2 229 240 10.1007/s00038-018-1182-7 30560293 15. Roberts C Freeman J Samdal O The health behaviour in school-aged children (HBSC) study: methodological developments and current tensions Int J Public Health 2009 54 2 140 150 10.1007/s00038-009-5405-9 19639259 16. Grzywacz JG Hovey JD Seligman LD Evaluating short-form versions of the CES-D for measuring depressive symptoms among immigrants from Mexico Hisp J Behav Sci 2006 28 3 404 424 10.1177/0739986306290645 31768090 17. Yu S-C Lin Y-H Hsu W-H Applying structural equation modeling to report psychometric properties of Chinese version 10-item CES-D depression scale Qual Quanti 2013 47 3 1511 1518 10.1007/s11135-011-9604-0 18. Salas-Wright CP Olate R Vaughn MG Assessing empathy in salvadoran high-risk and gang-involved adolescents and young adults: a Spanish validation of the basic empathy scale Int J Offender Ther Comp Criminol 2013 57 11 1393 1416 10.1177/0306624X12455170 22859664 19. Carlo G Hausmann A Christiansen S Sociocognitive and behavioral correlates of a measure of prosocial tendencies for adolescents Journal Early Adolesc 2003 23 1 107 134 10.1177/0272431602239132 20. Carlo G Randall BA The development of a measure of prosocial behaviors for late adolescents J Youth Adolesc 2002 31 1 31 44 10.1023/A:1014033032440 21. Carlo G McGinley M Hayes RC Empathy as a mediator of the relations between parent and peer attachment and prosocial and physically aggressive behaviors in Mexican American college students J Soc Pers Relat 2012 29 3 337 357 10.1177/0265407511431181 22. Davis AN Carlo G Schwartz SJ The longitudinal associations between discrimination, depressive symptoms, and prosocial behaviors in US Latino/a recent immigrant adolescents J Youth Adolesc 2016 45 3 457 470 10.1007/s10964-015-0394-x 26597783 23. Plante TG Ai AL Wink P Paloutzian RF The Santa clara strength of religious faith questionnaire (SCSRFQ): a brief, nondenominational, and multicultural assessment tool Assessing spirituality in a diverse world 2021 Cham Springer International Publishing 445 466 24. Salas-Wright CP Vaughn MG Hodge DR Religiosity profiles of American youth in relation to substance use, violence, and delinquency J Youth Adolesc 2012 41 12 1560 1575 10.1007/s10964-012-9761-z 22476727 25. Salas-Wright CP Vaughn MG Maynard BR Public or private religiosity: which is protective for adolescent substance use and by what pathways? Youth Soc 2017 49 2 228 253 10.1177/0044118X14531603 26. Szapocznik J Kurtines WM Fernandez T Bicultural involvement and adjustment in Hispanic-American youths Int J Intercult Relat 1980 4 3 353 365 10.1016/0147-1767(80)90010-3 27. Salas-Wright CP Maldonado-Molina MM Brown EC Cultural stress theory in the context of family crisis migration: implications for behavioral health with illustrations from the Adelante Boricua study Am J Crim Justice 2021 46 4 586 608 10.1007/s12103-021-09626-9 34248324 28. Salas-Wright CP Schwartz SJ The study and prevention of alcohol and other drug misuse among migrants: toward a transnational theory of cultural stress Int J Mental Health Addict 2019 17 2 346 369 10.1007/s11469-018-0023-5 29. Schwartz SJ Unger JB Lorenzo-Blanco EI Perceived context of reception among recent Hispanic immigrants: conceptualization, instrument development, and preliminary validation Cultur Divers Ethnic Minor Psychol 2014 20 1 1 15 10.1037/a0033391 24099485 30. Salas-Wright CP Oh S Vaughn MG A validation of the perceived negative context of reception scale with recently-arrived venezuelan immigrants in Colombia and the United States Cultur Divers Ethnic Minor Psychol 2021 27 4 649 658 10.1037/cdp0000455 34291972 31. Phinney JS Madden T Santos LJ Psychological variables as predictors of perceived ethnic discrimination among minority and immigrant adolescents1 J Appl Soc Psychol 1998 28 11 937 953 10.1111/j.1559-1816.1998.tb01661.x 32. Vermunt JK, Magidson J (2016) Upgrade manual for Latent GOLD 5.1, vol 1. Statistical Innovations, Belmont, pp 5–9 33. Celeux G Soromenho G An entropy criterion for assessing the number of clusters in a mixture model J Classif 1996 13 2 195 212 10.1007/BF01246098
PMC009xxxxxx/PMC9808727.txt	==== Front Clin Oral Investig Clin Oral Investig Clinical Oral Investigations 1432-6981 1436-3771 Springer Berlin Heidelberg Berlin/Heidelberg 36595064 4848 10.1007/s00784-022-04848-5 Research Comparison of hyaluronic acid, hypochlorous acid, and flurbiprofen on postoperative morbidity in palatal donor area: a randomized controlled clinical trial http://orcid.org/0000-0002-5939-4783 Alpan Aysan Lektemur [email protected] http://orcid.org/0000-0002-5362-4146 Cin Gizem Torumtay [email protected] grid.411742.5 0000 0001 1498 3798 Department of Periodontology, Faculty of Dentistry, Pamukkale University, Kınıklı Campus, 20160 Denizli, Turkey 3 1 2023 2023 27 6 27352746 1 7 2022 26 12 2022 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Objective This study aims to evaluate the effects of topical hyaluronic acid (HA), hypochlorous acid (HOCl), and flurbiprofen on postoperative morbidity of palatal donor sites after free gingival graft (FGG) surgery. Materials and methods Sixty patients requiring FGG were randomly assigned into four groups: control, HA gel (600 mg/100 g high molecular weight hyaluronic acid), HOCl spray (170–200 ppm, ph7.1), flurbiprofen spray (0.075gr flurbiprofen). Topical agents were applied for 14 days, according to groups. Patients were followed for 28 days. Palatal healing was assessed with the Laundry wound healing index (WHI). Complete epithelization (CE) was evaluated with photographs and H2O2 bubbling. Pain, burning sensation, chewing efficacy, and tissue color match (CM) were evaluated using a visual analog scale (VAS). Postoperative analgesic consumption and delayed bleeding (DB) were also recorded. Results HA provided better WHI values on the 7th, 14th, and 21st days compared to the other groups, respectively (p < 0.05). CE was formed on the 21st day in the HA group but on the 28th day in the other groups. HOCl and flurbiprofen groups were not different from the control group or each other in terms of WHI. HOCl had the lowest VAS scores of all time periods. DB was not observed in any group. Significantly fewer analgesics were taken in the topical agent-applied groups compared to the control group. Conclusions HA exhibits a positive impact on the epithelization of palatal wound healing and color matching. HOCl and flurbiprofen provided less pain; however, they might have negative effects on palatal wound healing. Clinical relevance As a result of obtaining free gingival grafts from palatal tissue for mucogingival surgical procedures, secondary wound healing of the donor area occurs. This wound in the palatal region can cause discomfort and pain every time patients use their mouths. The use of HA can reduce postoperative complications by accelerating wound healing and reducing pain. The topical use of flurbiprofen and HOCl can reduce patients’ pain. Keywords Operative Pain Plastic periodontal surgery Postoperative complications Surgical procedures Wound healing issue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction Free grafts from the palate have been used most commonly for gingival augmentation. It has been stated in the literature that free gingival graft (FGG) is one of the most reliable and frequently used methods to increase the amount of keratinized gingiva. In addition, this technique prevents and treats the progression of gingival recession, can eliminate aesthetic problems, and increases vestibular depth [1]. FGG leaves an open wound site due to the removal of the epithelial layer in the palatal region and heals in two to four weeks with secondary wound healing [2, 3]. However, some complications may occur at the recipient site. Excessive bleeding, postoperative bone exposure, bone exostoses, case of mucocele, severe postoperative pain, and recurrent herpetic lesions are the most documented complications [4–6]. Even if various materials with mechanical protection [7], platelet-rich fibrin (PRF) [8], herbal extract [5], and chemotherapeutic agents [9] are used in the donor area to prevent postoperative complications, there is no definite consensus. Flurbiprofen, 2(3-fluoro-4-phenyl–phenyl)-propionic acid, is a non-steroidal anti-inflammatory drug (NSAID) that has been shown to be safe and effective in relieving postoperative pain [10, 11]. Flurbiprofen in the form of an oral spray can be found commercially and simply applied to the palatal region directly. It has been found to inhibit the increase of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α, and interleukin (IL)-1β [12, 13], also reducing IL-6 expression [14] and inhibiting cyclooxygenase-2 (COX-2) expression [15]. Hypochlorous acid (HOCl) exhibits potent antimicrobial activities against a wide variety of microorganisms [16, 17]. HOCl, a naturally occurring molecule produced by neutrophils to destroy pathogens [18], is used in cosmetic and medical dermatological procedures due to its lack of microbe resistance, safety, and antimicrobial activity [17]. Hyaluronic acid (HA) is a natural polymer of glycosaminoglycans (GAGs) found in the joint synovial fluid and the extracellular matrix of the skin [19, 20]. It is naturally secreted during the proliferative phase of wound healing to stimulate migration and mitosis of fibroblasts and epithelial cells and has been shown to reduce levels of inflammatory mediators [21, 22]. It has been reported that HA has a positive effect on the healing of chronic wound ulcers of various etiologies, burns, and epithelial surgical wounds, regardless of the form in which it is administered topically (i.e., pad, cream, substrate) [23]. As a therapeutic agent, HA is used in tissue reconstruction [24], to accelerate wound healing [25, 26], in degenerative/inflammatory joint diseases, and in synovial fluid replacement [27, 28]. To the best of our knowledge, no studies have examined the effects of HOCl use on palatal wound healing after FGG surgery. The aim of this study was to compare the effects of locally applied HOCl, flurbiprofen, and HA on postoperative patient discomfort and wound healing of the palatal donor area in terms of pain, burning sensation, epithelialization, and color match after FGG surgery. Materials and methods Study pattern This study was designed as a prospective randomized controlled clinical trial with parallel groups. The population of the study consists of all patients who were referred to FGG for gingival augmentation between March 5, 2019, and March 15, 2022, at Pamukkale University Faculty of Dentistry Department of Periodontology. Procedures were explained to the participants, and all of them signed consent forms before participating in the study. The study was approved by Pamukkale University Ethical Committee (05.03.2019/05) and submitted to ClinicalTrials.gov (NCT05386667). All procedures performed in this study comply with the ethical standards of the institutional and/or national research committees and the Declaration of Helsinki and its subsequent amendments or comparable ethical standards. Inclusion criteria Patients with systematic conditions are classified as ASA Class I [29]. Patients > 18 years requiring FGG surgery with ≤ 1 mm width of attached gingiva in the mandibular anterior and premolar region Exclusion Criteria Pregnancy, lactation, and taking contraceptive pills Oversensitivity or anaphylactic reactions that contraindicate the intervention Orofacial neurological symptoms Infections at operation zone Psychotropic medicine, sedative, or NSAI use can alter the sense of pain Pathological mental conditions (dementia, psychosis) and lack of cooperation Patients who refuse to sign consent forms Excessive gag reflex Participants were randomly assigned to one of the 4 groups following a simple software-generated random number procedure via the “List Randomizer” application (https://www.random.org.lists). The power analysis of the study was carried out using the GPower software program (GPower v.3.1.9.2, Heinrich Heine University, Dusseldorf, Germany) accepting wound healing as the primary outcome variable. According to the power analysis of a previous study, the number of patients calculated for each group was 6, with α = 0.05, 1-β = 0.95, and f = 2.386 [7]. However, 15 patients for each group were included in the study, taking into account the loss of follow-ups (Fig. 1). All the patients received the initial periodontal therapy including scaling and root planning (SRP). Oral hygiene motivation was given to the patients, and they were recalled one month later. Full-mouth plaque score (FMPS) and full-mouth percentage bleeding score (FMBS) were recorded by assigning a binary score to each surface (1 for present, 0 for absent) and calculating the percentage of total tooth surfaces that revealed the presence of plaque/bleeding detected by the use of a periodontal probe (Hu-Friedy, Chicago, IL, USA) [30]. The number of teeth of the patients was also recorded.Fig. 1 Flow diagram generated in accordance with CONSORT 2010 guidelines Study groups Control group: No topical agent was applied to the palatal area where the FGG was harvested. Hyaluronic acid (HA) group: 600 mg/100 g high molecular weight hyaluronic acid (sodium salt) gel was applied twice daily for 14 days to the palatal area where the FGG was harvested. Hypochlorous acid (HOCl) group: 170–200 ppm, ph. 7.1 HOCl oral spray was applied twice daily for 14 days to the palatal area where the FGG was harvested. Flurbiprofen group: 0.075gr flurbiprofen and additives (sorbitol, saccharin sodium, glycerin, polyoxyl 40 hydrogenated castor oil, methyl paraben, propyl paraben, ethyl alcohol, patent blue E131 (blue), menthol, sodium hydroxide) included, the oral spray was applied twice daily for 14 days to the palatal area where the FGG was harvested. Surgical intervention In order to minimize the differences in surgical technique, all surgical procedures were performed with the same surgical technique by a single periodontist (ALA). The surgical application was applied by following the steps below briefly. After the palatal region was numbed with local infiltration anesthesia (2% lidocaine with 1:100,000 epinephrine), the area between the distal line angle of the canine and the mesial line angle of the first molar was marked as ≥ 2 mm away from the gingival margin, and a half-thickness incision was made. A FGG with a thickness of ≈1–1.5 mm and dimensions of 10 × 5 mm was obtained from the marked area with a scalpel no: 15C. The thickness was measured in the middle of the graft with an endodontic reamer and a caliper over a flat surface. The fat and glandular tissue were removed from the graft, and then the graft was shaped to adapt to the recipient site. Postoperative care The patients were prescribed an analgesic drug (500 mg of paracetamol). The patients in the study groups other than controls were given HA gel, HOCl, and flurbiprofen oral spray to be applied to the palatal wound areas. Patients who were received HOCl and flurbiprofen oral spray instructed to take one dose (three sprays) to the donor site twice a day for 14 days. HA gel was prescribed twice a day for 14 days to apply with its special applicator to the palatal wound area. In order not to disturb the stabilization of the clot formed in the operation area, all locally applied products were started 6–8 h after the operation. Patients were given instructions not to eat, drink, or rinse for about 30 min after spray/gel application and advised to report the outcome if any adverse events occurred. Patients were instructed to avoid any hard brushing or trauma to the surgical site for 3 weeks. All patients were monitored, and measurements were taken by one periodontist (GTC) on days 1, 3, 7, 14, 21, and 28. Patients were asked if they needed to use analgesics and to note the amount they used in the 7-day postoperative period. Evaluated parameters The primary outcome of the study was to measure the palatal wound healing status using the Landry Wound Healing Index (WHI) [31], which grades the wound healing on a scale of the 3rd, 7th, 14th, 21st, and 28th days postoperatively. This index, which has a score range of 1 (very poor) to 5 (excellent), evaluates tissue color, response to palpation, presence of granulation tissue, epithelialization of incision margins, and amount of suppuration. The secondary outcomes of the study were to measure patients’ perception of pain, discomfort while chewing, and burning sensation after FGG harvesting using a numerical rating scale (VAS) from 0 (no pain, no discomfort while chewing, no burning sense) to 10 (the worst pain imaginable, extreme discomfort while chewing, extreme burning sense) [32] on the 1st, 3rd, 7th, 14th, and 21st days, and the amount of analgesic consumption on the 1st, 3rd, and 7th days postoperatively. Tissue color match (CM) was assessed with adjacent and contralateral palatal tissue (0—no color matching to 10—excellent color matching) [32]. The patients were asked to keep a record of whether there was any bleeding in the palatal region, and at the same time, the presence of postoperative bleeding, also known as delayed bleeding (DB), was recorded as present ( +) or absent ( −) on the days when the patients came to the follow-up appointments. The epithelialization of the palatal region was recorded according to the application of 3% hydrogen peroxide to the region and whether there was foaming or not, and was calculated as a percentage (H2O2 bubbling) [33]. Complete epithelization (CE) was also evaluated clinically by monitoring the surface characteristics and clarity of the wound contour and recorded as “yes” or “no” [26]. Statistical analysis All data were evaluated with SPSS 21.0 (SPSS Inc., Chicago, IL). Shapiro–Wilk test was used to test the data’s normality. Since the data distributions were not normal, non-parametric tests were used to evaluate the analysis. The Chi-square test was used for demographic data (age, gender), CE, and DB. The number of teeth of the participants in all groups were compared with using one-way ANOVA post hoc Tukey test. Kruskal–Wallis post-hoc Mann–Whitney U with Bonferroni correction was applied to analyze the data of different groups (FMPS, FMBS, VAS pain, chewing, burning, WHI, CM, H2O2 bubbling, and analgesic consumption). The Friedman test was applied to evaluate the repeated measures within the groups. Data were expressed as min–max (median), mean ± standard deviation (SD), and frequency. p < 0.05 was considered statistically significant. Results A total of 60 patients took part in the study. The long duration of this study was due to the precautions taken during the COVID-19 pandemic. There was no drop-out among the 60 patients. All patients included in the study were followed for 28 days. Demographic data for the groups are presented in Table 1. FMPS, FMBS, and the number of teeth of all patients included in the study were similar between groups (p > 0.05). The patients participating in the study did not differ in terms of age and gender (p > 0.05). None of the patients developed adverse reactions to the agents used.Table 1 Demographic data and periodontal parameters. FMPS, full-mouth plaque score; FMBS, full-mouth percentage bleeding score Data were presented as mean ± SD, percentage. p < 0.05; the significant difference between groups Control HA HOCl Flurbiprofen p value Women 9(60%) 9(60%) 8(53.3%) 8(53.3%) 0.965 Man 4(40%) 6(40%) 7(46.7%) 7(46.7%) Age 37.20 ± 8.49 36.93 ± 9.04 36.33 ± 8.83 38.73 ± 9.76 0.886 Number of teeth 26.80 ± 1.47 26.60 ± 1.72 25.80 ± 1.78 26.13 ± 1.45 0.336 FMPS (%) 13.30 ± 2.21 13.09 ± 2.15 12.99 ± 1.92 12.55 ± 2.04 0.928 FMBS (%) 8.63 ± 1.47 8.65 ± 1.38 8.83 ± 1.56 8.68 ± 1.17 0.992 When our primary outcome, WHI, was examined, the HA group was found to be better in terms of wound healing scores compared to the HOCl group on the 3rd day (p = 0.019). The use of HA showed statistically better results in terms of wound healing compared to the control, flurbiprofen, and, HOCl groups on the 7th, 14th, and 21st days, respectively (Table 2, Fig. 2).Table 2 WHI, CM, H2O2 bubbling, and analgesic consumption of the groups. Data were presented as mean ± SD. p < 0.05; the significant difference between groups with the different superscripts Parameters Days Control n = 15 HA n = 15 HOCl n = 15 Flurbiprofen n = 15 p value WHI 3rd day 1.87 ± 0.32a,b 2.26 ± 0.45a 1.80 ± 0.41b 1.86 ± 0.35a,b 0.012 7th day 2.66 ± 0.48a 3.26 ± 0.45b 2.46 ± 0.51a 2.53 ± 0.51a 0.001 14th day 3.73 ± 0.45a 4.26 ± 0.45b 3.46 ± 0.51a 3.47 ± 0.52a 0.001 21st day 4.40 ± 0.50a 5.00 ± 0b 4.20 ± 0.41a 4.26 ± 0.59a 0.001 28th day 5.00 ± 0 5.00 ± 0 5.00 ± 0 5.00 ± 0 1 Color match (CM) 3rd day 4.33 ± 4.87a,b 11.33 ± 9.15a 3.33 ± 6.17b 6.66 ± 8.17a,b 0.022 7th day 18.66 ± 10.60a 40.66 ± 10.99b 22.66 ± 7.03a 21.33 ± 9.15a 0.001 14th day 59.33 ± 7.98a 78.66 ± 7.43b 60.66 ± 10.99a 58.00 ± 6.76a 0.001 21st day 83.33 ± 9.75a 95.33 ± 5.16b 86.66 ± 8.16a,b 80.66 ± 8.83a 0.001 28th day 96.00 ± 5.07a,b 100 ± 0a 96.66 ± 4.87a,b 95.33 ± 5.16b 0.029 H2O2 bubbling 3rd day 96.00 ± 6.32 96.00 ± 6.32 98.00 ± 4.14 97.33 ± 5.93 0.711 7th day 80.66 ± 8.83a 69.33 ± 10.32b 81.33 ± 7.43a 81.33 ± 8.33a 0.004 14th day 12.00 ± 9.41a,b 8.00 ± 9.41a 21.33 ± 11.87b 18.66 ± 12.45a,b 0.005 21st day 3.33 ± 4.87 0 5.33 ± 5.16 4.66 ± 5.16 0.011 28th day 0 0 0 0 1 Analgesic consumption 1st day 2.26 ± 0.70a 1.06 ± 0.88b 1.20 ± 0.77b 1.66 ± 0.72b 0.001 3rd day 2.20 ± 0.67a 1.10 ± 0.70b 0.66 ± 0.61b 1.33 ± 0.97b 0.001 7th day 0.33 ± 0.61 0.13 ± 0.35 0 0.35 ± 0.62 0.156 Fig. 2 Mean WHI values of groups When the VAS data, which evaluated the postoperative pain levels of the patients, were analyzed, the pain levels of the patients in the HOCl group were found to be significantly lower than in the flurbiprofen group (p = 0.007) and the control groups (p = 0.033) on the 1st day. On the 3rd day, patients in the HOCl group felt significantly less pain than those in the flurbiprofen (p = 0.030), and control groups (p = 0.001) respectively. Also, HA and flurbiprofen administration decreased the pain levels comparing the control group (p < 0.05). All study groups showed a statistical decrease in VAS values on the 7th day compared to the control group, respectively (p < 0.05). There was no difference between any group in terms of pain on the 14th and 21st days. The chewing efficiency of the patients in the HOCl group was found to be significantly better in the flurbiprofen (p = 0.001) and control groups (p = 0.016) on the 1st day, and in the control group (p = 0.033) on the 3rd day. HOCl reduced the burning sensation compared to the flurbiprofen group (p = 0.004) and the control group (p = 0.039) on the 1st day. The burning sensation on the 3rd and 7th day in all study groups was found to be significantly lower than the control group, respectively (p < 0.05) (Table 3, Fig. 3).Table 3 VAS pain, chewing, and burning values of groups. Data were presented as min–max (median). p < 0.05; the significant difference between groups with the different superscripts Parameters Days Control n = 15 HA n = 15 HOCl n = 15 Flurbiprofen n = 15 p value VAS pain 1st day 3–8(5)a 2–8(5)a,b 0–6(3)b 1–7(5)a 0.005 3rd day 5–8(7)a 1–5(3)b,c,d 0–3(2)c 1–6(3)d 0.001 7th day 3–6(5)a 0–3(1)b 0–1(0)b 0–4(1)b 0.001 14th day 0 0 0 0 1 21st day 0 0 0 0 1 VAS chewing 1st day 3–7(5)a 2–7(4)a,b 0–7(2)b 3–7(5)a 0.001 3rd day 2–7(4)a 0–5(3)a,b 0–4(2)b 1–6(3)a,b 0.021 7th day 0–2(1) 0–3(1) 0–2(0) 0–2(1) 0.134 14th day 0–2(0) 0 0 0 0.107 21st day 0 0 0 0 1 VAS burning 1st day 2–6(4)a 0–6(4)a,b 0–4(2)b 1–8(4)a 0.004 3rd day 3–8(6)a 0–4(2)b 0–3(1)b 1–7(3)b 0.001 7th day 4–8(6)a 0–3(0)b 0b 0–5(0)b 0.001 14th day 0–1(0) 0 0 0–2(0) 0.106 21st day 0 0 0 0 1 Fig. 3 Mean VAS pain, chewing, and burning values of groups HA group showed better CM with contiguous palatal tissue compared to the HOCl group (p = 0.037) on the 3rd day and those of all groups on the 7th and 14th days (p < 0.05). On day 21, the HA group had better results than the control (p = 0.003) and flurbiprofen (p = 0.001) groups, but on day 28, it achieved a better color match than flurbiprofen (p = 0.034) alone (Table 2, Fig. 4).Fig. 4 In situ images of groups on the operation, 3rd, 7th, 14th, 21st, and 28th days On the 7th day, the HA group showed less H2O2 bubbling than the control (p = 0.030), HOCl (p = 0.015), and flurbiprofen groups (p = 0.015).On the 14th and 21st days, HA showed significant differences only with HOCl and flurbiprofen (p < 0.05). On the 28th day, epithelialization was completed in all groups (Table 2). The photographs of palatal area were analyzed, and the CE was assessed visually. The HA group showed significantly better epithelialization than the HOCL and flurbiprofen groups on the 21st day (Fig. 4, Table 4). There was no difference between the groups in terms of delayed bleeding on the day of the 1st, 3rd, and 7th days postoperatively (Table 4, Fig. 4).Table 4 Complete epithelization (CE) and delayed bleeding (DB) values of the groups. Data were presented as count (%of total). p < 0.05; the significant difference between groups with the different superscripts Parameters Days Control n = 15 HA n = 15 HOCl n = 15 Flurbiprofen n = 15 p value Complete epithelization (CE) 3rd day No 15(100%) 15(100%) 15(100%) 15(100%) 7th day No 15(100%) 15(100%) 15(100%) 15(100%) 14th day No 11(73.3%) 7(46.7%) 12(80%) 11(73.3%) 0.054 Yes 4(26.7%) 8(53.3%) 3(20%) 4(26.7%) 21th day No 5(33.3%)a,b 0(0)a 8(53.3%)b 7(46.7%)b 0.010 Yes 10(66.7%)a,b 15(100%)a 7(46.7%)b 8(53.3%)b 28th day Yes 15(100%) 15(100%) 15(100%) 15(100%) Delayed bleeding (DB) 1st day No 8(53.3%) 12(80%) 7(46.7%) 11(73.3%) 0.181 Yes 7(46.7%) 3(20%) 8(53.3%) 4(26.7%) 3rd day No 10(66.7%) 14(93.3%) 10(66.7%) 12(80%) 0.200 Yes 5(33.3%) 1(6.7%) 5(33.3%) 3(20%) 7th day No 12(80%) 15(100%) 13(86.7%) 13(86.7%) 0.199 Yes 3(20%) 0(0) 2(13.3%) 2(13.3%) Discussion The most unfavorable condition after FGG surgery for patients is palatal donor site morbidity. Numerous clinical studies have focused on enhancing palatal wound healing and reducing patient discomfort [8, 26, 32, 33]. However, there is no study in the literature evaluating the effects of HOCl on palatal wound healing after periodontal plastic surgery. The present randomized clinical study was designed to investigate the therapeutic effects of different topical agents on the secondary wound healing of the donor palatal region and the patient's discomfort after the FGG procedure. The primary study outcome (WHI) indicated that the HA group revealed the best healing scores up to 21 days postoperatively. Concomitantly, higher rates of CE on the 14th day were observed in the HA group compared to the other study groups. However, HOCL resulted in lower VAS levels for the pain, chewing, and burning sensation parameters compared to the controls. Many steps are necessary for wound healing to take place, among them; cell differentiation, proliferation, migration, and collagen deposition [34, 35]. HA is a member of GAGs, which is the main component of the extracellular matrix (ECM) and has beneficial effects on wound healing by reducing inflammation, increasing vascularization, and collagen synthesis [36–38]. HA is involved in all steps of the wound-healing process [39]. Yıldırım et al. [26] compared two different high molecular weight HA gels (0.2% and 0.8%) in terms of donor site healing. According to the results, healing was found to be better in the 0.2% gel group on the 14th day, while both HA groups showed better epithelialization on the 21st day than the control. Chen et al. [40] reported that high molecular weight HA when combined with povidone-iodine, significantly improved wound healing, and promoted both cell proliferation and neovascularization at the wound site compared to low molecular weight HA. Increased fibroblast proliferation, rapid wound closure, and increased inflammatory cell infiltration have been reported after the topical application of HA [41]. In addition, in an animal study, it was found that the use of HA in the wound healing model in groups treated with HA increased the levels of fibroblast, collagen I, and collagen III consequently accelerating wound healing [42]. There are studies indicating that HA stimulates keratinocyte migration and proliferation and has a positive effect on re-epithelialization [43]. Since HA plays a curative role in every step of wound healing, we also obtained the best wound healing scores in the groups treated with HA in our study, and complete epithelialization was achieved in the HA group in 21 days compared to the other groups. In our study, VAS scores on the 3rd and 7th days were found to be lower in the HA group compared to the control group, and analgesic consumption of patients was lower in the HA group on the 1st and 7th days compared to the control group. After FGG surgery, locally applied HA gel (a mixture of cross-linked (1,6%) and natural (0,2%) HA) was compared with the control group and followed for six months. According to the results of the study, there was no difference between the two groups in terms of CM, and pain levels were higher in the control group compared to the HA group in the first seven days [44]. Hassan et al. [45] compared 0.2% HA gel, MEBO, and the control group, and it was found that the study groups showed significantly lower VAS scores on the 2nd and 3rd days compared to the control group. They stated that from the 4th day, the patients did not have any pain although there was no difference between the groups in terms of wound size at any time. These differences may be due to differences in HA molecular weight and concentration. In our study, we used high molecular weight HA at 0.6% concentration. High molecular weight HA exhibits anti-inflammatory and immunosuppressive properties. It has been reported that high molecular weight HA inhibited the IL-1β expression in a rabbit osteoarthritis study [46]. In an osteoarthritis model, high molecular weight HA downregulated IL-8 and the inducible nitrous oxide synthase gene expression and downregulated TNF-α gene expression in IL-1-stimulated fibroblast-like synoviocytes [47]. Campo et al. [48] found a reduction of mRNA expression and protein production for TNF-α, IL-1β, IL-17, matrix metalloproteinases-13, and the inducible nitrous oxide synthase gene in high molecular weight HA-treated arthritic mice. Furthermore high molecular weight HA was found to decrease the IL-1β, IL-6, TNF-α, and nitric oxide in microglial cells exposed to lipopolysaccharide [49]. Considering the necessity of increasing certain cytokines for the formation of acute pain, HA could decrease the perception of pain in patients by these mechanisms. As the risks of infectious diseases increase around the world, the need for an effective broad-spectrum antimicrobial agent is increasingly becoming a therapeutic imperative. Because it inactivates the SARS-CoV-2 virus, HOCl has become popular in dentistry as a disinfectant and antiseptic during the COVID-19 pandemic [50, 51]. Naturally, respiratory bursts during the activation of neutrophils produce peroxide (H2O2) and the activated granule enzyme myeloperoxidase converts H2O2 to HOCl in the presence of Cl− and H+ [52]. The resulting HOCl contributes to the bactericidal activity of neutrophils and is thought to cause tissue damage in areas of inflammation. In many studies, it has been stated that the use of HOCl has positive effects on wound healing [53]. In an in-vitro study, the effectiveness of NaClO/HClO solutions on wound healing was investigated and an increased antimicrobial effect was associated with decreased viability of keratinocytes and fibroblasts. The authors noted that the microbicidal effects almost always have a certain negative impact on cell proliferation and viability [54]. HOCl is a weak acid and an oxidant and also has high interaction potential with other molecules in a redox reaction, resulting in the formation of reactive oxygen species (ROS: hydrogen peroxide, superoxide, hydroxyl radicals, oxygen) [54, 55]. Excessive ROS may alter and/or degrade ECM proteins, resulting in impaired dermal fibroblast and keratinocyte function [56]. Considering the results of our study, lower WHI scores were obtained in the HOCl-administered group compared to the other groups, including the controls, in all time periods. Studies have also emphasized that HOCl is a selective oxidant that can easily react with cellular proteins like fibronectin, thrombospondin, and laminin, and may also cause extracellular matrix fragmentation and tissue denaturation [57, 58]. The resulting protein damage was found to be related to the amount of HOCl administered rather than the concentration [54, 58]. This result can be explained as follows: HOCl application causes an increased ROS in the palatal region and may result in a delay in wound healing. When HOCl and saline were compared in a histological study, although the number of methicillin-resistant Staphylococcus aureus (MRSA) was found to be decreased in the HOCl group compared to the control, there was no difference between the two groups in terms of epithelial thickness and granulation tissue formation [59]. In a randomized controlled trial (RCT) performed on the acute wound model, the use of HOCl was beneficial for epithelialization in the first days, but no difference was found in terms of re-epithelialization versus saline use on day 10. In addition, there was no significant difference between the two groups in VAS pain scores [60]. Mekkawy et al. [61] investigated the efficacy of HOCl on septic traumatic wounds in an RCT and found lower VAS scores up to 14 days than the control group, consistent with our study. In our study, pain, chewing, and burning scores evaluated by VAS in the HOCl group were found to be significantly lower than the control group up to 7 days. The side effect of a bacterial infection can be a tender, painful wound [62]. Proinflammatory cytokines such as ILs, TNF-α, granulocyte–macrophage colony-stimulating factor (GM-CSF), and monocyte chemoattractant protein-1 may be potential biomarkers for acute surgical wound pain [63]. HOCl has anti-inflammatory and immunomodulatory properties and reduces histamine, leukotriene B4, IL-6, and IL-2 activities [64]. Some authors have suggested that super-oxidized solutions act as a mast cell membrane stabilizing inhibitor, and diminish the mast-cell degranulation induced by IgE-antigen receptor cross-linking [65]. The fact that the VAS scores in our study were lower in the HOCl-administered groups than in the other groups may be the result of the suppression of inflammation due to the effects of HOCl, an antibacterial agent, on cytokine expression. Flurbiprofen decreases prostaglandin synthesis by inhibiting the COX-2 enzyme induced immediately in response to injury [66] but prostaglandins organize the cellular proliferation, vascular permeability, and angiogenesis, involved in wound healing [67]. In an animal model, COX-2 inhibitors caused delayed re-epithelialization in excisional wounds at cutaneous tissue [68]. Additionally, it was reported that COX-2 selective inhibitors resulted in significant inhibition of angiogenesis [69]. In wounded gastric epithelial cells, Pai et al. indicated that NSAIDs decrease both basal and epidermal growth factor induced re-epithelialization [70]. In our study, mean WHI values in the flurbiprofen group were similar for the control and HOCL groups at all-time points, but significantly lower than the HA group. Although the prevalence of CE was lower on the 21st day compared to the control group, it was not statistically significant. Isler et al. investigated the effects of topical flurbiprofen on the palatal donor site after both subgingival connective tissue graft (SCGT) and FGG procedures. According to their results, flurbiprofen resulted in delayed epithelization on the 21st day compared to the placebo group, and epithelization was completed within 42 days for all patients [33]. Contrary to these results, the prevalence of CE was 100% in 28 days in our study. It was shown that residual tissue thickness at the donor site after FGG harvesting affects the speed of palatal wound filling directly [71]. The lower graft thickness obtained in the present study may have resulted in faster re-epithelization in the palatal donor area. Many studies show that topically administered NSAIDs are effective in the management of postoperative pain after tonsillectomy [10, 72]. Koray et al. found similar VAS pain scores of NSAI spray (benzydamine hydrochloride) application compared to hyaluronic acid spray (0.2%) after third molar surgery [73]. In the study of Isler et.al, flurbiprofen spray decreased the VAS pain levels compared to the placebo group throughout the study period [33]. Consistent with the results of these studies, in the present study, VAS scores in the flurbiprofen group were similar HA group but were lower than controls on the 3rd and 7th days postoperatively. The present study had some limitations. VAS provides a subjective evaluation of the pain, chewing, and burning sensation rather than an objective parameter. Although the VAS scores showed a statistically significant difference between the groups at the time of evaluation, there was no difference between the groups in terms of analgesic consumption by the patients. Despite the statistically significant differences detected between groups, they may only be of very low clinical relevance. Also, using a locally applied therapeutic agent by patients may have caused them to report lower VAS scores in study groups compared to the controls. Another limitation of our study is the inability to examine cytokine expression by histological examination due to ethical barriers. Conclusion Clinicians should consider possible beneficial effects on the secondary wound healing process and patients’ discomfort; high molecular weight HA may be the first choice for the management of palatal donor site morbidity after FGG procedures. Although the use of HOCl and flurbiprofen reduced the pain compared to the control group, delayed epithelialization was observed due to possible effects on the inflammatory phase of wound healing. Author contribution Both authors have contributed equally to the work. Data Availability The data that support the findings of this study are available from the corresponding author, upon reasonable request. Declarations Competing interests The authors declare no competing interests. Ethics approval Permission was obtained from the Ethics Committee of Pamukkale University (05.03.2019/05) for the study protocol. Conflict of interest The authors declare no conflict of interest. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Camargo PM Melnick PR Kenney EB The use of free gingival grafts for aesthetic purposes Periodontol 2000 2001 27 72 96 10.1034/j.1600-0757.2001.027001072.x 11551301 2. Farnoush A Techniques for the protection and coverage of the donor sites in free soft tissue grafts J Periodontol 1978 49 403 405 10.1902/jop.1978.49.8.403 288907 3. Burkhardt R Hammerle CH Lang NP Research Group on Oral Soft Tissue BWound H Self-reported pain perception of patients after mucosal graft harvesting in the palatal area J Clin Periodontol 2015 42 281 7 10.1111/jcpe.12357 25544993 4. Griffin TJ Cheung WS Zavras AI Damoulis PD Postoperative complications following gingival augmentation procedures J Periodontol 2006 77 2070 2079 10.1902/jop.2006.050296 17209793 5. Keceli HG Aylikci BU Koseoglu S Dolgun A Evaluation of palatal donor site haemostasis and wound healing after free gingival graft surgery J Clin Periodontol 2015 42 582 589 10.1111/jcpe.12404 25892528 6. Roccuzzo A Imber JC Bosshardt D Salvi GE Sculean A Development of bone exostosis following the use of a free gingival graft: a 30-year case report and literature review Int J Periodont Restor Dent 2021 41 539 545 10.11607/prd.5035 7. Yussif N Wagih R Selim K Propylene mesh versus acrylic resin stent for palatal wound protection following free gingival graft harvesting: a short-term pilot randomized clinical trial BMC Oral Health 2021 21 208 10.1186/s12903-021-01541-z 33902550 8. Ustaoglu G Ercan E Tunali M The role of titanium-prepared platelet-rich fibrin in palatal mucosal wound healing and histoconduction Acta Odontol Scand 2016 74 558 564 10.1080/00016357.2016.1219045 27538770 9. Kozlovsky A Artzi Z Hirshberg A Israeli-Tobias C Reich L Effect of local antimicrobial agents on excisional palatal wound healing: a clinical and histomorphometric study in rats J Clin Periodontol 2007 34 164 171 10.1111/j.1600-051X.2006.01033.x 17309591 10. Turk B Akpinar M Erol ZN Kaya KS Unsal O Coskun BU The effect of flurbiprofen oral spray and ibuprofen vs ibuprofen alone on postoperative tonsillectomy pain: an open, randomised, controlled trial Clin Otolaryngol 2018 43 835 840 10.1111/coa.13058 29288561 11. Muderris T Tezcan G Sancak M Gul F Ugur G Oral flurbiprofen spray for postoperative sore throat and hoarseness: a prospective, randomized, double-blind, placebo-controlled study Minerva Anestesiol 2019 85 21 27 10.23736/S0375-9393.18.12703-9 29756749 12. Ooki A Del Carmen Rodriguez Pena M Marchionni L Dinalankara W Begum A Hahn NM VandenBussche CJ Rasheed ZA Mao S Netto GJ Sidransky D Hoque MO YAP1 and COX2 coordinately regulate urothelial cancer stem-like cells Cancer Res 2018 78 168 181 10.1158/0008-5472.CAN-17-0836 29180467 13. Aich A, Wang C, Chowdhury A, Ronsor C, Pacheu-Grau D, Richter-Dennerlein R, Dennerlein S, Rehling P (2018) COX16 promotes COX2 metallation and assembly during respiratory complex IV biogenesis. Elife 7. 10.7554/eLife.32572 14. Jiang WW Wang QH Peng P Liao YJ Duan HX Xu M Li Y Zhang PB Effects of flurbiprofen axetil on postoperative serum IL-2 and IL-6 levels in patients with colorectal cancer Genet Mol Res 2015 14 16469 16475 10.4238/2015.December.9.18 26662445 15. Wang X Ye X Zhang Y Ji F Flurbiprofen suppresses the inflammation, proliferation, invasion and migration of colorectal cancer cells via COX2 Oncol Lett 2020 20 132 10.3892/ol.2020.11993 32934701 16. Robson MC Payne WG Ko F Mentis M Donati G Shafii SM Culverhouse S Wang L Khosrovi B Najafi R Cooper DM Bassiri M Hypochlorous acid as a potential wound care agent: part II. stabilized hypochlorous acid: its role in decreasing tissue bacterial bioburden and overcoming the inhibition of infection on wound healing J Burns Wounds 2007 6 e6 17492051 17. Gold MH Andriessen A Bhatia AC Bitter P Jr Chilukuri S Cohen JL Robb CW Topical stabilized hypochlorous acid: the future gold standard for wound care and scar management in dermatologic and plastic surgery procedures J Cosmet Dermatol 2020 19 270 277 10.1111/jocd.13280 31904191 18. Wang L Bassiri M Najafi R Najafi K Yang J Khosrovi B Hwong W Barati E Belisle B Celeri C Robson MC Hypochlorous acid as a potential wound care agent: part I. Stabilized hypochlorous acid: a component of the inorganic armamentarium of innate immunity J Burns Wounds 2007 6 e5 17492050 19. Graca MFP Miguel SP Cabral CSD Correia IJ Hyaluronic acid-based wound dressings: a review Carbohydr Polym 2020 241 116364 10.1016/j.carbpol.2020.116364 32507198 20. Gencer ZK Ozkiris M Okur A Korkmaz M Saydam L A comparative study on the impact of intra-articular injections of hyaluronic acid, tenoxicam and betametazon on the relief of temporomandibular joint disorder complaints J Craniomaxillofac Surg 2014 42 1117 1121 10.1016/j.jcms.2014.01.041 24853591 21. Prosdocimi M Bevilacqua C Exogenous hyaluronic acid and wound healing: an updated vision Panminerva Med 2012 54 129 135 22525567 22. Voigt J Driver VR Hyaluronic acid and wound healing Wound Repair Regen 2012 20 317 331 10.1111/j.1524-475X.2012.00777.x 22564227 23. Voigt J Driver VR Hyaluronic acid derivatives and their healing effect on burns, epithelial surgical wounds, and chronic wounds: a systematic review and meta-analysis of randomized controlled trials Wound Repair Regen 2012 20 317 331 10.1111/j.1524-475X.2012.00777.x 22564227 24. Neuman MG Nanau RM Oruna-Sanchez L Coto G Hyaluronic acid and wound healing J Pharm Pharm Sci 2015 18 53 60 10.18433/j3k89d 25877441 25. Humbert P Mikosinki J Benchikhi H Allaert FA Efficacy and safety of a gauze pad containing hyaluronic acid in treatment of leg ulcers of venous or mixed origin: a double-blind, randomised, controlled trial Int Wound J 2013 10 159 166 10.1111/j.1742-481X.2012.00957.x 22405094 26. Yildirim S Ozener HO Dogan B Kuru B Effect of topically applied hyaluronic acid on pain and palatal epithelial wound healing: an examiner-masked, randomized, controlled clinical trial J Periodontol 2018 89 36 45 10.1902/jop.2017.170105 28914592 27. Bergstrand S Ingstad HK Moystad A Bjornland T Long-term effectiveness of arthrocentesis with and without hyaluronic acid injection for treatment of temporomandibular joint osteoarthritis J Oral Sci 2019 61 82 88 10.2334/josnusd.17-0423 30814387 28. Iturriaga V Vasquez B Bornhardt T Del Sol M Effects of low and high molecular weight hyaluronic acid on the osteoarthritic temporomandibular joint in rabbit Clin Oral Investig 2021 25 4507 4518 10.1007/s00784-020-03763-x 33392807 29. Günaydın B ASA Fiziksel Durum Sınıflandırma Sistemi: ASA Physical Status Classification System Turk J Anaesthesiol Reanim 2021 49 192 193 33997856 30. Guerrero A Griffiths GS Nibali L Suvan J Moles DR Laurell L Tonetti MS Adjunctive benefits of systemic amoxicillin and metronidazole in non-surgical treatment of generalized aggressive periodontitis: a randomized placebo-controlled clinical trial J Clin Periodontol 2005 32 1096 1107 10.1111/j.1600-051X.2005.00814.x 16174275 31. Landry RG Effectiveness of benzydamine HC1 in the treatment of periodontal post-surgical patients 1985 Faculty of Dentistry, University of Toronto 32. Lektemur Alpan A Torumtay Cin G PRF improves wound healing and postoperative discomfort after harvesting subepithelial connective tissue graft from palate: a randomized controlled trial Clin Oral Investig 2020 24 425 436 10.1007/s00784-019-02934-9 31104113 33. Isler SC Eraydin N Akkale H Ozdemir B Oral flurbiprofen spray for mucosal graft harvesting at the palatal area: a randomized placebo-controlled study J Periodontol 2018 89 1174 1183 10.1002/jper.17-0381 30007054 34. Broughton G 2nd Janis JE Attinger CE The basic science of wound healing Plast Reconstr Surg 2006 117 12S 34S 10.1097/01.prs.0000225430.42531.c2 16799372 35. Velnar T Bailey T Smrkolj V The wound healing process: an overview of the cellular and molecular mechanisms J Int Med Res 2009 37 1528 1542 10.1177/147323000903700531 19930861 36. Aya KL Stern R Hyaluronan in wound healing: rediscovering a major player Wound Repair Regen 2014 22 579 593 10.1111/wrr.12214 25039417 37. Frenkel JS The role of hyaluronan in wound healing Int Wound J 2014 11 159 163 10.1111/j.1742-481X.2012.01057.x 22891615 38. Kasuya A Tokura Y Attempts to accelerate wound healing J Dermatol Sci 2014 76 169 172 10.1016/j.jdermsci.2014.11.001 25468357 39. Litwiniuk M Krejner A Speyrer MS Gauto AR Grzela T Hyaluronic acid in inflammation and tissue regeneration Wounds 2016 28 78 88 26978861 40. Chen RF Wang CT Chen YH Chien CM Lin SD Lai CS Wang CJ Kuo YR Hyaluronic acid-povidone-iodine compound facilitates diabetic wound healing in a streptozotocin-induced diabetes rodent model Plast Reconstr Surg 2019 143 1371 1382 10.1097/prs.0000000000005504 30807498 41. Tolg C Telmer P Turley E Specific sizes of hyaluronan oligosaccharides stimulate fibroblast migration and excisional wound repair PLoS ONE 2014 9 e88479 10.1371/journal.pone.0088479 24551108 42. Taskan MM Balci Yuce H Karatas O Gevrek F Isiker Kara G Celt M Sirma Taskan E Hyaluronic acid with antioxidants improve wound healing in rats Biotechnol Histochem 2021 96 536 545 10.1080/10520295.2020.1832255 43. Nyman E Henricson J Ghafouri B Anderson CD Kratz G Hyaluronic acid accelerates re-epithelialization and alters protein expression in a human wound model Plast Reconstr Surg Glob Open 2019 7 e2221 e2221 10.1097/GOX.0000000000002221 31333952 44. Khalil S Habashneh RA Alomari S Alzoubi M Local application of hyaluronic acid in conjunction with free gingival graft: a randomized clinical trial Clin Oral Invest 2022 26 2165 2174 10.1007/s00784-021-04197-9 45. Hassan A Ahmed E Ghalwash D Elarab AE Clinical comparison of MEBO and hyaluronic acid gel in the management of pain after free gingival graft harvesting: a randomized clinical trial Int J Dent 2021 2021 2548665 2548665 10.1155/2021/2548665 34426739 46. Takahashi K Goomer RS Harwood F Kubo T Hirasawa Y Amiel D The effects of hyaluronan on matrix metalloproteinase-3 (MMP-3), interleukin-1beta(IL-1beta), and tissue inhibitor of metalloproteinase-1 (TIMP-1) gene expression during the development of osteoarthritis Osteoarthritis Cartil 1999 7 182 190 10.1053/joca.1998.0207 47. Wang CT Lin YT Chiang BL Lin YH Hou SM High molecular weight hyaluronic acid down-regulates the gene expression of osteoarthritis-associated cytokines and enzymes in fibroblast-like synoviocytes from patients with early osteoarthritis Osteoarthritis Cartil 2006 14 1237 1247 10.1016/j.joca.2006.05.009 48. Campo GM, Avenoso A, Nastasi G, Micali A, Prestipino V, Vaccaro M, D’Ascola A, Calatroni , Campo S (2011) Hyaluronan reduces inflammation in experimental arthritis by modulating TLR-2 and TLR-4 cartilage expression. Biochim Biophysica Acta (BBA) Mol Basis Dis 1812:1170–1181. 10.1016/j.bbadis.2011.06.006 49. Austin JW Gilchrist C Fehlings MG High molecular weight hyaluronan reduces lipopolysaccharide mediated microglial activation J Neurochem 2012 122 344 355 10.1111/j.1471-4159.2012.07789.x 22587438 50. Block MS Rowan BG Hypochlorous acid: a review J Oral Maxillofac Surg 2020 78 1461 1466 10.1016/j.joms.2020.06.029 32653307 51. Hatanaka N Yasugi M Sato T Mukamoto M Yamasaki S Hypochlorous acid solution is a potent antiviral agent against SARS-CoV-2 J Appl Microbiol 2022 132 1496 1502 10.1111/jam.15284 34480823 52. Vissers MC Winterbourn CC Oxidation of intracellular glutathione after exposure of human red blood cells to hypochlorous acid Biochem J 1995 307 Pt 1 57 62 10.1042/bj3070057 7717994 53. Joachim D Wound cleansing: benefits of hypochlorous acid J Wound Care 2020 29 S4 S8 10.12968/jowc.2020.29.Sup10a.S4 33016847 54. Severing A-L Rembe J-D Koester V Stuermer EK Safety and efficacy profiles of different commercial sodium hypochlorite/hypochlorous acid solutions (NaClO/HClO): antimicrobial efficacy, cytotoxic impact and physicochemical parameters in vitro J Antimicrob Chemother 2018 74 365 372 10.1093/jac/dky432 55. Armstrong DG Bohn G Glat P Kavros SJ Kirsner R Snyder R Tettelbach W Expert recommendations for the use of hypochlorous solution: science and clinical application Ostomy Wound Manag 2015 61 S2 s19 56. Moseley R Stewart JE Stephens P Waddington RJ Thomas DW Extracellular matrix metabolites as potential biomarkers of disease activity in wound fluid: lessons learned from other inflammatory diseases? Br J Dermatol 2004 150 401 413 10.1111/j.1365-2133.2004.05845.x 15030321 57. Woods AA Davies MJ Fragmentation of extracellular matrix by hypochlorous acid Biochem J 2003 376 219 227 10.1042/BJ20030715 12911330 58. Vissers MCM Thomas C Hypochlorous acid disrupts the adhesive properties of subendothelial matrix Free Radic Biol Med 1997 23 401 411 10.1016/S0891-5849(96)00619-3 9214576 59. Davis SC Gil J Li J Simms C Valdes J Solis M Higa A Effect of mechanical debridement and irrigation with hypochlorous acid wound management solution on methicillin-resistant Staphylococcus aureus contamination and healing deep dermal wounds in a porcine model Wound Manag Prev 2021 67 24 31 10.25270/wmp.2021.8.2431 34370678 60. Burian EA, Sabah L, Kirketerp-Møller K, Gundersen G, Ågren MS (2022) Effect of stabilized hypochlorous acid on re-epithelialization and bacterial bioburden in acute wounds: a randomized controlled trial in healthy volunteers. Acta Dermato-Venereol 102:adv00727. 10.2340/actadv.v102.1624 61. Mekkawy MM Kamal A A randomized clinical trial: the efficacy of hypochlorous acid on septic traumatic wound J Educ Pract 2014 5 89 100 62. Zhao G Usui ML Lippman SI James GA Stewart PS Fleckman P Olerud JE Biofilms and inflammation in chronic wounds Adv Wound Care (New Rochelle) 2013 2 389 399 10.1089/wound.2012.0381 24527355 63. Goto T Saligan LN Wound pain and wound healing biomarkers from wound exudate: a scoping review J Wound Ostomy Continence Nurs 2020 47 559 568 10.1097/won.0000000000000703 33201141 64. Del Rosso JQ Bhatia N Status report on topical hypochlorous acid: clinical relevance of specific formulations, potential modes of action, and study outcomes J Clin Aesthet Dermatol 2018 11 36 39 30588272 65. Medina-Tamayo J Sánchez-Miranda E Balleza-Tapia H Ambriz X Cid ME González-Espinosa D Gutiérrez AA González-Espinosa C Super-oxidized solution inhibits IgE-antigen-induced degranulation and cytokine release in mast cells Int Immunopharmacol 2007 7 1013 1024 10.1016/j.intimp.2007.03.005 17570318 66. Davies NM Clinical pharmacokinetics of flurbiprofen and its enantiomers Clin Pharmacokinet 1995 28 100 114 10.2165/00003088-199528020-00002 7736686 67. Ricciotti E FitzGerald GA Prostaglandins and inflammation Arterioscler Thromb Vasc Biol 2011 31 986 1000 10.1161/ATVBAHA.110.207449 21508345 68. Fairweather M Heit YI Buie J Rosenberg LM Briggs A Orgill DP Bertagnolli MM Celecoxib inhibits early cutaneous wound healing J Surg Res 2015 194 717 724 10.1016/j.jss.2014.12.026 25588948 69. Masferrer JL Koki A Seibert K COX-2 inhibitors. A new class of antiangiogenic agents Ann N Y Acad Sci 1999 889 84 86 10.1111/j.1749-6632.1999.tb08726.x 10668485 70. Pai R Szabo IL Giap AQ Kawanaka H Tarnawski AS Nonsteroidal anti-inflammatory drugs inhibit re-epithelialization of wounded gastric monolayers by interfering with actin, Src, FAK, and tensin signaling Life Sci 2001 69 3055 3071 10.1016/s0024-3205(01)01412-6 11758831 71. Keskiner I Aydogdu A Balli U Kaleli AE Quantitative changes in palatal donor site thickness after free gingival graft harvesting: a pilot study J Clin Periodontol 2016 43 976 984 10.1111/jcpe.12592 27330024 72. Muderris T Gul F Yalciner G Babademez MA Bercin S Kiris M Oral flurbiprofen spray for posttonsillectomy pain Otolaryngol Head Neck Surg 2016 155 166 172 10.1177/0194599816637865 26980919 73. Koray M Ofluoglu D Onal EA Ozgul M Ersev H Yaltirik M Tanyeri H Efficacy of hyaluronic acid spray on swelling, pain, and trismus after surgical extraction of impacted mandibular third molars Int J Oral Maxillofac Surg 2014 43 1399 1403 10.1016/j.ijom.2014.05.003 24924267
PMC009xxxxxx/PMC9816544.txt	==== Front J Brand Manag Journal of Brand Management 1350-231X 1479-1803 Palgrave Macmillan UK London 308 10.1057/s41262-022-00308-3 Original Article It takes a village: examining how and when brand-specific transformational leadership affects employees in internal brand management http://orcid.org/0000-0001-7986-7202 Xiong Lina [email protected] Lina Xiong is an Assistant Professor in Department of Human Dimensions of Natural Resources, Colorado State University. She has a Ph.D. in Business Administration with concentration in tourism and hospitality management. Her research focuses on service brand management and internal branding in service organizations. She publishes in top academic journals in hospitality and marketing. She emphasizes a sense of purpose and wellbeing in her research and life. grid.47894.36 0000 0004 1936 8083 Department of Human Dimensions of Natural Resources, Warner College of Natural Resources, Colorado State University, Fort Collins, CO 80523 USA 6 1 2023 2023 30 4 333346 30 11 2022 21 12 2022 © The Author(s), under exclusive licence to Springer Nature Limited 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. The hospitality work environment presents many unique challenges for employees and organizations, such as the intertwined and collective work nature, implicit job expectations, and a shrinking labor market. The demand for highly skilled employees who are sufficient to deliver the unique brand values to customers is on the rise for building successful service brands through employees. The need to retain talented employees is further intensified by the “great resignation” movement in the USA along with the COVID-19 pandemic. This study demonstrates the positive role of brand-specific transformational leadership in promoting employees’ highly engaged brand building behavior (investment-of-self) and their resistance to outside competing job offers. More importantly, drawing upon cognitive dissonance theory, this study shows that the impact of brand-specific transformational leadership is mediated by employees’ sense of brand community internally, as well as moderated by perceived brand promise accuracy. These results supported the essential role of achieving employees’ cognitive consonance in brand communication both internally and externally. These results are supported by 203 US hospitality employee responses from multiple data collections purposefully designed with temporal and cognitive distance. Keywords Brand-specific transformational leadership Hospitality organizations Employee sense of brand community Cognitive dissonance theory Brand promise accuracy issue-copyright-statement© Springer Nature Limited 2023 ==== Body pmcIntroduction The importance of a hospitality business building a strong brand is well established. However, sustaining a strong and competitive hospitality brand goes beyond creating, designing, and communicating the brand promise to customers. This is because the customers’ actual brand experiences are heavily influenced by hospitality employees’ attitudes and behavior during service encounters (Xiong and King 2019). For example, Southwest Airlines employees often embody the “Don’t take yourself too seriously” brand value by interacting with customers in a humorous manner, which contributes to the airline’s success (Sampson 2019). If employee performance is inconsistent with customers’ previously held brand expectations established through external brand communication (e.g., the brand promise), customers are less likely to develop brand satisfaction or loyalty (Murillo and King 2019). Therefore, internal brand management (IBM) has become an important topic in both academic research and industry practices for hospitality businesses (Buil et al. 2016). IBM focuses on aligning employees’ attitudes and behavior with specific brand values so that they are able to deliver the promised brand experience to customers. Considering the intangibility and variability of service products, it is often difficult to prescribe a set of standard procedures to satisfy every customer request and brand expectation. Nonetheless, hospitality employees from different departments are expected to create consistent and coherent brand experiences that are aligned with an organization’s promoted brand to meet customer expectations (Xiong and King 2020). For example, a customer’s overall brand experience at an amusement park is developed through his/her interactions with ticketing agents, ride operators, equipment rental agents, food and beverage sellers, safety staff, etc. In addition, as service employees’ day-to-day job performance often requires interactions with coworkers, the social environment within the organization also plays a significant role in affecting employees’ decision-making. Therefore, when seeking to deliver such brand-aligned experiences, researchers have argued for the importance of leadership when ensuring employees are motivated and proficient at creating and adapting their own set of knowledge and skills, as well as curating an internal community in delivering the brand promise to customers (Barros-Arrieta and García-Cali 2021; Buil et al. 2019). However, there is a lack of understanding of the type of leadership that can effectively promote employees’ brand supporting attitudes and behavior in the internal branding context. The role of leadership is expected to be even more critical for hospitality organizations in the USA with the COVID-19 pandemic. Described as “the great resignation,” industry experts and academic scholars pointed to the phenomenon where employees are increasingly leaving their current jobs for external opportunities (Leonhardt 2021; Rosenbaum and Ramirez 2022). This trend hurts low-paying in-person service jobs the most, such as jobs in leisure and hospitality industries (U.S. Bureau of Labor Statistics 2021). For example, in November 2021, almost a million employees in leisure and hospitality industries in the USA quit and most of them (92%) were in accommodation and food services. Employees today have more power to choose organizations that work better for their needs and wants. In addition to seeking better pay and work-life balance, reports show that employees also want better organizational cultures and practices that treat them more as human beings, a sense of community with social and emotional support, as well as development opportunities (De Smet et al. 2021). Thus, in order to avoid the “big regret” of losing employees, service organizations need to rethink their internal marketing practices. Previous literature has highlighted transformational leadership (TFL) as an effective leadership style that binds followers together in reaching a higher collective goal as well as creates a sense of community for followers (e.g., Powell 2020; Uen et al. 2012). A transformational leader emphasizes, to his or her employees, the collective outcome of their job behavior and the value of belonging to something larger than themselves (Brown and Treviño, 2006). Eberly et al. (2017) further suggested TFL decreases followers’ turnover intentions in extreme contexts, such as natural disasters. In previous internal branding studies, TFL is also shown to contribute to employees’ brand-supporting behavior, both in-role (e.g., standard job responsibilities) and extra-role (e.g., helping coworkers) (Buil et al. 2019; Uen et al. 2012). Although it is expected that general TFL contribute to employee brand-aligned performance, there is a paucity of research that articulates the impact of brand-specific TFL on employees as well as the mechanisms of such an impact. As it is critical to highlight the relevance and meaningfulness of brand values to employees when they are expected to deliver brand-aligned experiences to customers (Xiong et al. 2013), this study adopts the brand-specific TFL term proposed in Morhart et al. (2009) to highlight the intentional emphasis of brand values in TFL. Compared to the definition of TFL that focuses on the leadership style that transforms followers in general (e.g., Pieterse et al. 2010), brand-specific TFL describes “a leader’s approach to motivating his or her followers to act on behalf of the corporate brand by appealing to their values and personal convictions” (Morhart et al. 2009, p. 123). In short, this study focuses on how and when brand-specific TFL affects employees’ brand-supporting behaviors in internal branding. Considering the growing IBM literature (e.g., Piehler et al. 2019; Xiong and King 2018) that emphasizes employees’ social learning behaviors (i.e., learning through observing others in the organization), as well as the collective work nature of providing a holistic brand experience to customers, this study draws upon communities of practice literature (Wenger and Snyder 2000) and identifies the central roles of an internal employee-based brand community in IBM. Specifically, based on previous IBM research, this study proposes that brand-specific TLF is positively associated with employees’ investment-of-self in brand building and employee competitive resistance to outside job offers, both of which are strong indicators of employees’ brand-supporting behavior. More importantly, based on the communities of practice literature, it is proposed that this effect is mediated by employee sense of brand community. This study further draws upon cognitive dissonance theory (Festinger 1957) and identifies the moderating role of employee perceived brand promise accuracy between brand-specific TFL and employee sense of brand community. As such, these findings expand current IBM research through identifying the mechanism of brand-specific TFL in promoting employees’ brand-supporting behaviors. Practical insights with respect to enhancing the effectiveness of TFL for hospitality organizations as well as strengthening employees’ sense of belonging and shared passion through building a sense of brand community are provided accordingly. Literature review The effect of brand-specific TFL on employees in internal branding TFL and brand-specific TFL have been discussed in several internal branding studies (e.g., Buil et al. 2019; Chiang et al. 2020) and are consistently identified as positive drivers of employees’ brand-aligned performance for a few reasons. First, there are four aspects of transformational leadership, including idealized influence (e.g., manifest charisma and instill pride in followers/subordinates), inspiration (e.g., communicate purpose and share the organizational vision), intellectual stimulation (e.g., help followers gain new perspectives and set high performance standards), and individualized consideration (e.g., provide individual attention and coaching) (Avolio et al. 1999; Bass 1985). As a result of these characteristics, TFL is highly recommended in organizational environments where employees are encouraged and expected to engage creatively and develop innovative solutions at work (e.g., Jaiswal and Dhar 2015). This is consistent with the internal branding management context where brand knowledge in terms of the brand identity, values, and the skills necessary to bring out the brand uniqueness during service encounters is highly tacit (King and Grace 2009; Xiong et al. 2013). As brand-specific TFL further emphasizes employees’ internalization of brand values through empowering, modeling, and coaching (Morhart et al. 2009), employees are more likely to draw upon not just the organization-provided brand information, but also their own experiences and intuition to create brand-consistent experiences for customers. Second, as employees are expected to go above and beyond their prescribed job roles to deliver an authentic brand experience for customers in the internal branding context, researchers have argued for the importance of employees developing a strong internal motivation to deliver extra-role performance (Xiong and King 2015; Xiong and King 2018). Previous research suggests that employees need to perceive the meaningfulness and relevance of the brand as well as the importance of their role in affecting the overall brand success in order to be motivated to deliver extra-role brand-aligned performance (King and Grace 2006; Xiong and King 2015). Transformational leaders are inspirational, able to articulate compelling and relevant brand visions for employees and can promote a higher level of self-involvement from employees. This enables employees to rise above their self-interest and deliver higher-than-expected performance (Bass 1985; Brown and Treviño, 2006; Pieterse et al. 2010). Therefore, brand-specific TFL is likely to drive employees to go above and beyond the prescribed job duties and become brand ambassadors (Morhart et al. 2009). Third, the creation of a holistic, brand-consistent experience requires seamless collaboration among service employees across different departments within the organization. Transformational leadership is an effective leadership style in fostering a teamwork-oriented environment that promotes the value of belonging to something larger than oneself or one’s department while emphasizing organization-wide outcomes to employees (Bass 1985; Brown and Treviño, 2006). Transformational leaders can further satisfy employees’ inherent needs for relatedness and role identity in building self-concept (Morhart et al. 2009). Thus, brand-specific TFL is likely to foster a positive work environment that gears toward providing a coherent brand experience to customers. Although previous literature supports brand-specific TFL’s roles in promoting employees in-role and extra-role performance (e.g., Morhart et al. 2009), the focus was on job performance or general work engagement (e.g., Buil et al. 2019). There is a lack of consideration of effective indicators that lead to employees’ subsequent brand-aligned performance. Therefore, this study expands on current brand-specific TFL studies by examining its impact on more immediate outcomes of brand-specific TFL. Given these recommended research directions and drawing on recent research advancement in internal branding, this study focuses on brand-specific TFL’s role in affecting employees’ investment-of-self in brand building and competitive resistance to employment opportunities in other organizations. The following sections provide the theoretical foundation for each proposed link. Employee investment-of-self in brand building Rooted in the psychological ownership literature (e.g., Brown et al. 2014; Pierce et al. 2001, 2003), employee investment-of-self in internal brand management describes the extent to which an employee invests his/her personal time, skills, ideas, and energies into delivering the brand promise to customers. Xiong et al. (2019) demonstrated that when employees invest their personal resources into brand building, they are likely to develop psychological ownership of the brand and elicit extra-role behaviors even when such behaviors are considered risky to their job status (e.g., voicing concerns and providing constructive feedback to management). Compared to employees’ organization/brand-based identification that suggests employees develop self-concepts by “attaching” themselves to the organization/brand, employees’ psychological ownership of the brand reflects employees actively taking the brand into their domain (Xiong et al. 2019), which contributes to their strong sense of care and responsibility toward the brand naturally (Chang et al. 2012; Xiong et al. 2019). Although investment-of-self has been recognized as the most powerful means to the development of psychological ownership (Pierce et al. 2001) as well as extra-role behaviors in internal brand management (Xiong et al. 2019) for employees, it is unclear how brand-specific TFL may affect this positive employee outcome. According to Morhart et al. (2009), brand-specific transformational leaders act as role models by living the brand. They inspire and motivate employees to internalize the vision, mission, and values of the brand (i.e., “own the brand”) and become brand champions. Transformational leaders are also proficient at encouraging employees’ creativity and innovative solutions (Jaiswal and Dhar 2015), which is a crucial skill for employees to create consistent and coherent brand experiences during service encounters. As followers of such leaders, employees are more likely to invest their personal resources (e.g., ideas, time, energy, and creativity) into delivering the brand promise. Hypothesis 1 is presented below: H1 Brand-specific transformational leadership is positively associated with employee investment-of-self in brand building. Employee competitive resistance In recent years, tourism and hospitality organizations have faced many challenges in finding and retaining high-value employees due to a shrinking workforce (Pearlman and Schaffer 2013) and unfavorable work conditions such as irregular work hours and work stress (Xiong and King 2019). As a result, tourism and hospitality organizations often suffer from an increase in turnover rate, decreased service quality and customer satisfaction, as well as an increase in hiring costs (Coy 2006). These challenges are even more pressing in the internal branding context as employees are further expected to devote their judgment, experiences, and intuition in delivering brand-aligned experiences for customers (Xiong and King 2015). Considering that high employee turnover can be detrimental and costly for organizations (Park and Shaw 2013), it is critical to examine how to retain employees when they are presented with competing external job opportunities. Following the conceptualization of customer competitive resistance, which is defined as a customer’s intention to disregard competing offers from other providers (Asatryan and Oh 2008; Reynolds and Arnold 2000), this study proposes the term of employee competitive resistance to describe the employee intention to stay with the brand when facing outside competing job offers. This term is distinct from employee retention or employee turnover intention which are often used in previous literature (e.g., Tse et al. 2013) to describe the general employee intention to stay with the organization in the short and long term. Employees may choose to stay in an organization due to the lack of outside offers while employee competitive resistance further considers the “pull-to-leave” force from outside of the organization. Therefore, it may represent a higher level of employee commitment to the organization. However, the extent to which TFL may affect employee competitive resistance lacks examination. The relationship between TFL and employee retention is supported in previous studies. Based on the social exchange theory, Tse et al. (2013) suggested that when employees perceive mutual trust, loyalty, and positive emotions from TFL, they are more likely to feel “obligated” to reciprocate by staying with the organization. In addition, TFL also fosters positive social exchanges, instills a sense of community among employees, and helps them view their jobs from a community member’s perspective (Chun et al. 2016; Herman et al. 2013; Morhart et al. 2009). Thus, TFL’s role in retaining followers can remain strong even in extreme contexts (e.g., military combat, natural disasters) as TFL increases the bond between followers and their roles as well as others in the organization (Eberly et al. 2017). This binding force is likely to be stronger under brand-specific TFL as employees are encouraged to adopt the brand values into their self-concepts (Morhart et al. 2009), which forms a common ground for developing a strong and unique employee brand bond as well as social relationships among employees. In addition, embodying the organization’s brand is considered a potential employer brand attractiveness attribute (Lievens and Highhouse 2003; Ronda et al. 2018). Thus, employees are likely to be more resistant to outside employment opportunities under brand-specific TFL. In addition, as employees invest more of their own effort, time, energy, and ideas into building the brand, they are likely to develop a sense of psychological ownership toward the brand (i.e., this brand is mine) (Xiong et al. 2019). Based on psychological ownership studies (Brown et al. 2014; Pierce et al. 2001), with a higher level of investment-of-self in brand building, employees are likely to perceive a higher value of the brand and develop stronger intentions to protect and enhance the brand performance. Subsequently, they are more likely to value that brand more than competing brands and develop resistance against outside job offers. Hypothesis 2 and 3 are presented as follows. H2 Brand-specific transformational leadership is positively associated with employee competitive resistance. H3 Employee investment-of-self has a positive impact on employee competitive resistance. The mediating role of employee sense of brand community With the identified important roles of TFL, researchers have advocated for a deeper theoretical understanding of TFL by examining potential mediators and moderators of its impact on employee behaviors and attitudes (Avolio et al. 2004). In the context of internal branding, hospitality employees are expected to not only provide quality services, but also to internalize the brand values and perform in a brand-aligned manner to meet customers’ brand expectations (Xiong and King 2019). In this process, leaders and managers play an important role in transmitting the organizational expectations to employees. However, the effect of leadership on employee attitudes and behavior may not be straightforward. According to Moreland et al. (2001), compared to organizational socialization between management and employees, work group socialization can have a stronger influence on employees. This argument is consistent with the two-step flow process in communication theory (Katz and Paul 1955; Watts and Dodds 2007). That is, compared to direct media influence, individuals are more likely to be influenced by intermediaries between the media and people around them (Katz and Paul 1955). Considering frontline employees are likely to interact with their coworkers more often than their leaders and managers, it is likely that brand-specific TFL’s influence on employees is likely to be both direct and indirect through this community of practice. According to communities of practice literature (Wenger 2011; Wenger and Snyder 2000), when individuals share concerns or passion for something they do, they are likely to form a community of practice and engage in collective learning in order to achieve a better outcome. As such, they are more likely to experience a sense of belonging to the community of practice. In the context of internal branding, Xiong and King (2020) suggest that when employees are expected to internalize tacit brand values into their daily performance, they are likely to build an internal brand community and rely on this community to learn and exchange their expertise and passion with coworkers in brand building (Xiong and King 2020). For example, coworkers can provide important complementary job knowledge as well as implicit insider information to fellow employees (Xiong and King 2018), which may provide a more realistic picture of the organizational expectations (Miles and Mangold 2004). That is, this internal employee community can help employees to make sense of the implicit brand values and decrease potential perceived inconsistency between formal brand knowledge dissemination from management and informal brand knowledge and skills exemplified by coworkers. As such, employees are more likely to internalize brand values into their brand delivery to customers. Therefore, it is proposed that the impact of brand-specific TFL on employees is also indirect (mediated) through an internal employee brand community. When employees develop a strong sense of brand community internally, they are likely to develop social and emotional connections with coworkers, gain important insider information about the organization, and clarify implicit organizational expectations of their roles (Xiong and King 2020). As such, employees are also likely to perceive the brand as “our brand” and elicit a higher level of investment-of-self in brand building. Along the same logic, employees are also less likely to withdraw from the organization when they develop strong bonds with coworkers and perceive they are valuable members of an internal community (Liaw et al. 2010; Tse et al. 2013). Thus, they are also likely to develop stronger competitive resistance to outside employment offers. The mediating role of employee sense of brand community is hypothesized as follows: H4 The relationship between brand-specific transformational leadership and employees’ investment-of-self is mediated by employee’s sense of brand community. H5 The relationship between brand-specific transformational leadership and employees’ competitive resistance is mediated by employee’s sense of brand community. The moderating role of perceived brand promise accuracy Further, considering TFL influences employees through communication, role modeling, coaching, it is further important to consider factors that may affect this process, such as how employees are affected by external brand communication targeting customers (Piehler et al. 2019). One particular factor is the extent to which employees perceive the externally communicated brand promise to be accurate and consistent with their brand perception. As shown in advertising studies (e.g., Celsi and Gilly 2010), employee attitudes and behavior are also affected by advertising targeting external consumers (i.e., spillover effect). It is not uncommon for employees to perceive discrepancy between internal and external communication (Celsi and Gilly 2010). In such a case, employees are likely to experience cognitive dissonance due to conflicting cognitions of the brand. As suggested in Festinger (1957), when individuals experience cognitive dissonance, they are likely to feel discomfort. This unpleasant state motivates them to seek ways to decrease the experienced dissonance. Such dissonance reduction practices can include changing cognitions, adding/subtracting cognitions, or adjusting the importance of cognitions (Hinojosa, et al. 2017). Thus, based on cognitive dissonance theory (Festinger 1957), when employees perceive the externally communicated brand promise to be inaccurate or inconsistent with their brand perceptions, they are likely to experience cognitive dissonance which may propel subsequent dissonance reduction behaviors. For instance, employees may alter their original cognition and think the organization/management is not true to its words and therefore discount their trust toward and confidence in the leadership and organization (Miles and Mangold 2004). This can be detrimental for TFL (Braun et al. 2013). Employees are also likely to adjust the importance of the cognitions by discounting the importance of incorporating brand values into their work performance, which dampens the effect of brand-specific TFL. Along the same logic, when employees perceive a high level of brand promise accuracy, they are more likely to experience cognitive consonance and value congruence with the organization (Celsi and Gilly 2010), which should promote employee information exchange, communication effectiveness, and a friendly organizational environment (Xiong and King 2015). Therefore, employee perceived brand promise accuracy may moderate the impact of brand-specific TFL. H6 is presented as follows: H6 The relationship between brand-specific transformational leadership and employees’ sense of brand community is positively moderated by employees’ perceived brand promise accuracy. In summary, building upon transformational leadership research and internal branding literature, this study proposes that brand-specific TFL’s impact on employees’ investment-of-self into brand building and their competitive resistance to outside offers is mediated by employees’ sense of an internal brand community and moderated by perceived brand promise accuracy. Figure 1 presents the proposed relationships. The following sections provide a detailed description of how these relationships are assessed with empirical data collected from US-based hospitality employees in multiple periods.Fig. 1 Proposed relationships Method Measures All measurement items were adopted from existing literature with demonstrated reliability and validity. Brand-specific transformational leadership was measured by eight items reflecting leadership characteristics (i.e., intellectual stimulation, inspirational motivation, idealized influence in terms of both attributes and behaviors, and individual consideration) in an internal branding context from Morhart et al. (2009). The Cronbach’s alpha for this measurement was 0.96. Employees’ sense of brand community was measured using the 8-item sense of brand community scale from Xiong and King (2020) developed based on McMillan and Chavis (1986). The Cronbach’s alpha for this construct was 0.95 in this study. Employee competitive resistance was measured based on the adaption of the customer competitive resistance in Reynolds and Arnold (2000) and Asatryan and Oh (2008). An example item is “I will continue working in my organization even if there are attractive job offers from its competitors.” The Cronbach’s alpha was 0.84. Employee investment-of-self was measured using the corresponding measurement items from Xiong and King (2018) and yielded a Cronbach’s alpha of 0.89. Lastly, perceived brand promise accuracy was measured with four items regarding marketing message accuracy in Seriki et al. (2016) with adaptation to the internal branding context. An example item is “Our brand marketing materials provide accurate information.” The Cronbach’s alpha for this measure was 0.86. All items were retained with no further adjustment (Table 1).Table 1 Measurement details Constructs and items Mean s.d Standardized loading t value* Brand-specific transformational leadership My manager… 1. Seeks different perspectives when interpreting our organization’s brand values 4.96 1.721 0.753 – 2. Suggests a brand promoter’s perspective of looking at how to do my job 5.22 1.605 0.863 13.230 3. Articulates a compelling vision of our organization’s brand 5.21 1.675 0.840 12.817 4. Expresses confidence that brand-related goals will be achieved 5.56 1.463 0.841 12.841 5. Instills pride in me for being associated with our organization’s brand 5.35 1.615 0.899 13.909 6. Lives our organization’s brand in ways that build my respect 5.22 1.695 0.869 13.357 7. Spends time teaching and coaching me in brand-related issues 5.06 1.762 0.884 13.637 8. Helps me to develop my strengths with regard to becoming a good representative of our brand 5.35 1.647 0.919 14.292 Employee sense of brand community 1. I can get what I need working in this brand community 5.24 1.513 0.887 – 2. This brand community helps me fulfill my needs 5.12 1.602 0.903 19.582 3. I feel like a member of the community that works for this brand 5.36 1.545 0.912 20.091 4. I belong in this brand community 5.34 1.548 0.880 18.435 5. I have a say about what goes on in this brand community 4.48 1.945 0.694 11.987 6. People in this brand community are good at influencing each other 5.30 1.426 0.785 14.676 7. I feel connected to this brand community 5.33 1.509 0.895 19.168 8. I have a good bond with others in this brand community 5.50 1.411 0.716 12.535 Employee competitive resistance 1. I disregard job offers from other brands 4.20 1.744 0.768 – 2. I will continue working in my organization even if there are attractive job offers from its competitors 4.38 1.846 0.856 11.866 3. I would rather work for a different brand than my current organization’s brand. (Reverse-coded) 4.87 1.722 0.820 11.516 Employee investment-of-self 1. I have invested a major part of “myself” into delivering the brand promise to customers 5.40 1.503 0.823 – 2. I have invested many of my ideas into building the brand 4.78 1.736 0.720 11.178 3. I have invested a number of my talents into this delivering the brand promise to customers 5.68 1.323 0.673 10.259 4. I have invested a significant amount of my life into building the brand 4.84 1.706 0.833 13.610 5. In general, I have invested a lot in building the brand 5.04 1.562 0.867 14.340 Employee perceived brand promise accuracy 1. Our brand marketing materials provide accurate information 5.76 1.320 0.835 – 2. I feel I can deliver what our brand ads promise 5.89 1.192 0.742 11.730 3. Our brand marketing materials exaggerate how great our service is (reverse-coded) 5.27 1.658 0.701 14.107 4. Our brand marketing materials give customers a pretty good idea what they can expect from us 5.71 1.294 0.849 10.880 s.d. refers to standardized deviation; – means paths set to 1 p < 0.001 To limit common method bias resulting from self-reported data in cross-sectional surveys, following suggestions in Lindell and Whitney (2001), an a priori marker variable (intention to purchase organic food) that is not theoretically associated with the focal constructs in the questionnaire was included. The inclusion of this marker variable enabled researchers to estimate the extent of common method bias in later analysis. All items were measured using a 7-point Likert scale, with 1 representing the lowest rating of agreement and 7 representing the highest rating of agreement. Table 1 provides the details of the measures with corresponding factor loading results revealed in later analyses. Data collection Participants were recruited from US-based hospitality employees with facilitation from a survey research company (Qualtrics) before the COVID-19 pandemic. In addition to reaching target populations in an efficient and effective manner, Qualtrics also provided an online survey system where several systematic measures were applied to disqualify abnormal responses (e.g., conflicting responses, and responses completed in far less than average completing time). Anonymity and confidentiality of respondents were ensured as the researchers received no identifying information from the survey platform. Considering survey insights are self-reported, in order to aid objectivity of responses and limit respondents’ perceived saliency among questions in the same survey, special attention was paid to the introduction of temporal and cognitive distance among closely related construct questions (MacKenzie and Podsakoff 2012; Podsakoff et al. 2003). The antecedent variables and outcome variables were deliberately separated in two rounds of surveys to the same individual respondent. The first survey only contained questions regarding outcome variables and demographic information. The second survey only contained questions regarding the antecedent variables. As the survey platform assigned a unique identifier number to each panel member, the responses from the same respondent that completed both surveys were matched. In the first round, the survey platform randomly selected 1500 current US-based hospitality employees from large panels and the first round of surveys were distributed via subjects’ registered emails (hidden from researchers). In this round, four hundred fifty-seven valid responses (i.e., responses with no missing values) were received (response rate = 30.5%). After a four-week period (Crossley et al. 2007), a second round of data collection was conducted by sending questions regarding antecedent variables to the 457 respondents who provided completed responses in the first round. One hundred and eighteen valid survey responses were received in this round (25.8% of the initial surveys sent out). The responses from the second round were matched with responses from the first round based on the unique identifier information of each respondent. As a result, 118 full responses were collected. Each full response contains the responses to questions in both surveys from the same individual respondent. This four-week lag that separated data collections of antecedent variables and outcome variables can reduce the potential for common method bias, as respondents are less likely to be influenced by the saliency among questions if they are placed in different surveys (Crossley et al. 2007; MacKenzie and Podsakoff 2012). Following Crossley et al. (2007) and Karatepe (2012), a four-week lag was decided to limit respondents’ memory decay. However, a drawback to using this method is that it often suffers from lower response rate (Crossley et al. 2007). In order to warrant a robust examination of the proposed structural relationships among the focal constructs while ensuring sample quality, a third round of data collection was conducted by obtaining a new sampling pool of US-based hospitality employees (about 800). This sample excluded individuals who were involved in the first two rounds of data collection. Due to research time and budget constraints, all questions were included in this survey and distributed to this new sampling pool of potential respondents. In seeking to decrease common method bias in this situation, several remedies were adopted following Podsakoff et al. (2003). Specifically, a random sequence was applied in arranging the questions to counterbalance the order of the measurement of the antecedent and outcome variables. Different anchor points (e.g., evaluation of leaders, agreements with statements, and perceived accuracy of statements) were also adopted in different questions to reduce the perceived commonalities in scale endpoints. Consistent with previous rounds of data collection, attention filter questions, marker variable questions, and completion time threshold were also included. As a result, 85 valid responses were collected in this round. Combined with the 118 previously full responses, a final dataset of 203 responses was used for this study. Although the sample size of 203 may be viewed as relatively small for structural analyses, Iacobucci (2010) and Hair et al. (2006) suggested that sample size consideration should also be based on model characteristics and model complexity. When the variables are reliable and effects are strong, a small sample size (e.g., 150) can be sufficient for a proper solution (Iacobucci 2010; Xiong and King 2019). In addition, considering the rigid procedures adopted in enhancing data quality (e.g., marker variable, temporal distance among multiple data collections), it is argued that the sample size of 203 was sufficient for this study. Sample profile Of the 203 respondents, about three-fourths (74.4%) identified themselves as hotel employees while the remainder (25.6%) were restaurant employees. Approximately three-fourths (73.9%) of the respondents were female. About four in ten respondents (41.4%) were aged 25–34, with just under one-fourth (23.6%) being 35–44 years old. Less than one-third of respondents have worked in their organization for 1–3 years (31.0%), and for 3–5 years (29.6%), respectively. Approximately three-fourths (75.9%) of the respondents held full-time positions in their organization. Two-thirds (67.5%) of the respondents held entry-level and supervisor positions. Two-thirds (66.2%) of the respondents identified their organizations to be at a 4–5 star level. Just under three-fourths (72.4%) of the organization brands were identified as chain brands as opposed to independent brands. Brand training was suggested to be fairly common among the respondents. Over one-fourth (28.8%) of respondents reported that their organizations host brand-related training monthly and approximately one-fifth of respondents (21.7%) received such training every 2–3 months. Only 4.4 percent of respondents indicated they never received such training. Data analyses Preliminary analyses were conducted to assess data consistency and the extent of common method bias. First, a series of t-tests and Chi-square tests were conducted to compare responses to the same questions from different rounds of data collection. No significant differences were identified, demonstrating consistency across data collection events. Second, potential nonresponse bias was assessed through a wave analysis (Rogelberg and Stanton 2007). Specifically, the first 30 responses and last 30 responses in each data collection were compared through independent sample t-tests. No significant differences were found, demonstrating limited nonresponse bias. Third, as mentioned before, a theoretically unrelated marker variable was included to account for the potential common method bias (Lindell and Whitney 2001). All relationships remained significant after including the marker variable in the measurement model check (Table 2). The correlations between the marker variable and the variables of interest in this study were also assessed. The correlation values ranged from 0.187 to 0.279. Subsequently, following the recommendations in Lindell and Whitney (2001) as well as Coelho et al. (2018), the smallest correlation between the marker variable and the variables of interest (0.187) was regarded as a proxy estimate of the common method bias and was partialled out. The adjusted correlations lend further support to the measurement validity of this study. Lastly, the researchers checked the potential multivariate normality issues by assessing the skewness and kurtosis of each item’s distribution. The skewness and kurtosis values met the normality recommendations by Byrne et al. (2013). Thus, in order to examine the underlying structural relationships among the focal constructs, a two-step structural equation model (SEM) analysis (Anderson and Gerbing 1988) using SPSS AMOS 24 using maximum likelihood estimation was conducted.Table 2 Correlation, composite reliability (CR), and average variance extracted (AVE) CR AVE 1 2 3 4 5 1. Brand-specific TFL 0.958 0.739 0.860 2. Sense of brand community 0.949 0.702 0.637 0.838 3. Investment-of-self 0.890 0.619 0.292 0.353 0.787 4. Competitive resistance 0.856 0.665 0.352 0.529 0.305 0.815 5. Perceived accuracy 0.864 0.615 0.636 0.750 0.236 0.455 0.784 The square root of each construct’s AVE value is shown in bold and italic in diagonal space. Values below the diagonal are the correlations among constructs In the first step measurement model check, a good model fit was achieved with χ2 = 611.615 (p < 0.001, df = 339); χ2/df = 1.80, CFI = 0.95, TLI = 0.94; RMSEA = 0.06, SRMR = 0.05). As shown in Table 1, all standardized factor loading values were statistically significant (p < 0.0001) and were above 0.65. The Cronbach’s α values were 0.96, 0.95, 84, 0.89, and 0.86, respectively, in the order shown, supporting good measurement reliability. The average variance extracted (AVE) values for all constructs were above 0.6 (Table 2), suggesting the majority of variance in each construct was explained by the measurement items. Composite reliability (CR) values for all constructs were above 0.85. Taken together, convergent validity was supported (Anderson and Gerbing 1988; Fornell and Larcker 1981; Hair et al. 2006). With respect to discriminant validity, as shown in Table 2, the square roots of respective AVE value were larger than respective adjusted cross-correlations among the variables of interest, lending support for discriminant validity (Fornell and Larcker 1981). The heterotrait–monotrait (HTMT) ratios for each variable of interest were also calculated to further assess discriminant validity following Henseler et al. (2015). Since all of the HTMT ratios (ranged from 0.396 to 0.8) were below the conservative cutoff value of 0.85 (Henseler et al. 2015), they provided complementary support for discriminant validity in this study. With the established validity of the measurement model, the hypotheses were tested through SEM via SPSS AMOS 24 using maximum likelihood estimation. Two relevant control variables (tenure and position level) were included in the following analyses as they may affect employees’ experiences with the organizational leadership (Bernerth and Aguinis 2016). As shown in Table 3 (direct effect model), the independent variable (i.e., brand-specific TFL) has a significant impact employee investment-of-self (β = 0.43, p < 0.001) and competitive resistance (β = 0.36, p < 0.001) directly. Employee investment-of-self also has a positive impact on competitive resistance (β = 0.27, p < 0.001). Thus, H1, H2 and H3 were supported. In addition, the control variable employee tenure showed a significant impact on employee investment-of-self (β = 0.23, p < 0.001). It is noted that this direct effect model test (e.g., tests for H1 and H2) are not necessary for the mediation tests for H4 and H5 statistically (Zhao et al. 2010). However, they are necessary for testing H1 and H2, both of which are proposed based on previous literature.Table 3 Path estimates in direct effect model and indirect effect model for mediation tests Path Direct effect model Indirect effect model TFL → Investment-of-self 0.43(5.568) n.s TFL → Competitive resistance 0.36(4.29)* n.s Investment-of-self → Competitive resistance 0.27(3.13)* 0.178(2.317)* TFL → Brand community – 0.705(9.640)* Brand community → Investment-of-self – 0.347(3.461)* Brand community → Competitive resistance – 0.50(4.909)* R2 Investment-of-self 0.28 0.241 Competitive resistance 0.29 0.408 Brand community – 0.496 Fit indices χ2 236.233 572.422 Df 127 287 χ2/df 1.86 1.995 CFI 0.96 0.936 TLI 0.95 0.927 RMSEA 0.065 0.070 TFL refers to brand-specific transformational leadership; investment is short for investment-of-self; brand community is short for employees’ sense of brand community; each value in the box shows the standardized path estimate p < 0.001; p < 0.05; t value is placed in parentheses; – this path is not included in the model; n.s. means not significant H4 and H5 propose that the relationships between brand-specific TFL and the two outcome variables are mediated through employee sense of brand community. Following MacKinnon et al. (2004), employee sense of brand community was included in the structural analysis and the mediated (indirect) effects were identified through a bootstrapping procedure (2000 samples) with a 95% confidence interval and bias-corrected percentile method. The results showed that brand-specific TFL has a significant standardized indirect effect on employee investment-of-self (95% CI [0.18, 0.48]), p < 0.05), as well as on employee competitive resistance (95% CI [0.33, 0.56]), p < 0.05). Under this analysis, the strength of the positive relationships between brand-specific TFL and employee investment-of-self as well as competitive resistance dropped to an insignificant level (Indirect effect model in Table 3), suggesting an indirect-only mediation effect described in Zhao et al. (2010). Thus, H4 and H5 were supported. With respect to the hypothesized moderating role of perceived brand promise accuracy (H6) between brand-specific TFL and employee sense of brand community, the procedures recommended by Aiken et al. (1991) in testing interaction effects were followed. This procedure is widely adopted organizational behavior research (e.g., Liu and Cho 2018). Specifically, brand-specific TFL and perceived brand promise accuracy were mean-centered. An interaction term was created by multiplying the two mean-centered terms. The interaction term (brand-specific TFL × perceived brand promise accuracy), brand-specific TFL and perceived brand promise accuracy were then included in the structural model as three antecedent variables linking to employee sense of brand community. Other paths stayed the same. The bootstrapping technique (2000 samples) with a 95% confidence interval and bias-corrected percentile method was applied to obtain more details of the moderation effect. This interaction model also demonstrated good model fit (χ2 = 737.598 (p < 0.001, df = 414); χ2/df = 1.782, CFI = 0.936, TLI = 0.928; RMSEA = 0.06). The interaction term contributed to sense of brand community (β = 0.105, p < 0.05). Almost seventy percent (69.8%) of variance of employee sense of brand community was explained. The significant relationships between sense of brand community to the two outcome variables remained strong and positive (β = 0.45 for invest-of-self, and β = 0.54 for competitive resistance). The moderation effects was further evaluated based on the low and high levels of perceived brand promise accuracy (Table 4). It is shown that at a high level of perceived brand promise accuracy (i.e., the value is one standard deviation above the mean), brand-specific TFL has a strong and positive impact on employee sense of brand community (β = 0.429, p < 0.05). That is, when employees perceive the externally communicated brand promise to be highly consistent with their brand perceptions, they are more likely to experience a sense of community as a result of brand-specific TFL. However, when perceived brand promise accuracy is at a low level (i.e., the value is one standard deviation below the mean), the impact of brand-specific TFL on employee sense of brand community becomes insignificant (β = 0.186, p = 0.157). Therefore, H6 is supported.Table 4 The effects of brand-specific TFL on employee brand community at high and low levels of perceived brand promise accuracy β Stand error p BootLLCI BootULCI − 1SD 0.186 0.136 0.157 − 0.069 0.463 Mean 0.308 0.108 0.005 0.095 0.529 + 1SD 0.429 0.134 0.003 0.17 0.694 − 1SD refers to one standard deviation below the mean value of perceived brand promise accuracy (i.e., the low level). Mean refers to the mean value of perceived brand promise accuracy. + 1SD refers to one standard deviation above the mean value of perceived brand promise accuracy (i.e., the high level) BootLLCI bootstrap lower-level confidence interval, BootULCI bootstrap upper-level confidence interval Discussion and theoretical implications This study draws from cognitive dissonance theory to consider how employees process brand knowledge dissemination from formal management/leadership, informal community of coworkers, and the brand promise communicated to customers. Lower perceived cognitive dissonance helps employees to make sense of the implicit organizational expectations and engage in brand building. Specifically, this study examined how and when brand-specific TFL affects employee investment-of-self in brand building and competitive resistance to outside offers. This study found that brand-specific TFL plays a positive and significant role in promoting both. The findings also demonstrated brand-specific TFL effects through employee sense of an internal brand community and is moderated by perceived brand promise accuracy based on cognitive dissonance theory. This study is consistent with previous studies that demonstrated the positive roles of TFL in community building (Chun et al. 2016) as well as positive outcomes of a strong sense of brand community among employees (Xiong and King 2020). This study contributes to internal branding literature by examining how and when brand-specific TFL works in hospitality organizations where seamless collaboration among service employees are required to deliver the brand promise to customers. The strong mediation effect of employee sense of brand community is in line with Morhart et al. (2009), Chun et al. (2016) and Tse et al. (2013) that suggested TFL’s impact can be mediated by social exchanges among employees, which contributed to employees’ role identification in brand building and relatedness to brand community. This study further provides a cognitive dissonance perspective to explain how brand-specific TFL affects employees’ investment-of-self and competitive resistance through employee sense of brand community. In addition, this study supports the spillover effects of external marketing communication (e.g., advertising) (Celsi and Gilly 2010) on employees, which is rarely discussed in internal brand management. Along with the cognitive dissonance arguments in supporting the role of an internal brand community, this study further shows that brand-specific TFL’s effect on employees is stronger when employees perceive the brand promise to be accurate, reducing potential cognitive dissonance between internal and external brand communication. Further, it also indicates that the relationship between brand-specific TFL and employee sense of brand community holds even when employees perceive the brand promise to be inconsistent with their brand perceptions, further supporting the positive roles of TFL in deterring external pull-to-leave forces for employees (Mitchell et al. 2001). This study also contributes to both TFL and internal branding literature by expanding brand-specific TFL’s roles in encouraging employee retention, especially when they are enticed with outside offers. Xiong and King (2020) examined employee sense of community in an internal branding context and suggested that it contributes to employees’ brand belief and brand-aligned performance. This study adds to the understanding of employee sense of brand community by showing the significant antecedent role of brand-specific TFL. In addition, previous studies commonly adopt employee retention or organizational commitment under TFL (e.g., Tse et al. 2013) with limited consideration of contextual factors such as competitive job offers. With employees increasingly seeking meaning and purpose within their employment post-pandemic, this finding is highly timely for cultivating and retaining talented employees in service branding through leadership. Also, it is well-established that employees are expected to go beyond their prescribed roles to deliver brand-aligned experiences in internal branding (Xiong and King 2015). This expectation may require a higher level of employee devotion and perceived ownership of brand success (Xiong and King 2018). This study built upon this notion and incorporated employee investment-of-self from psychological ownership studies (e.g., Brown et al. 2014; Pierce et al. 2001) as a highly relevant outcome of internal branding, which is propelled by brand-specific TFL and employee sense of community. Practical implications With the demonstrated effects of brand-specific TFL and its boundary conditions in internal branding, the study presents important managerial implications. First, consistent with Buil et al. (2019) and Morhart et al. (2009), it is believed that brand-specific TFL is a desired leadership style for hospitality organizations that seek to build and sustain a successful brand through employees’ brand-aligned performance. As noted in Morhart et al. (2009), managers are likely to achieve better outcomes in internal branding when they promote a unified brand vision, live the brand values, coach employees to develop their interpretation of brand-aligned performance, and provide individualized support to employees. Thus, it is recommended that brand-specific TFL should be infused into recruiting, training, evaluating, and promoting processes of managers in hospitality organizations. In addition, the ability to foster a supportive internal brand community, enhance employees’ willingness to stay with the organization in a competitive labor market, and promote employees’ self-devotion to brand building are suggested as effective measures to evaluate brand-specific transformational leaders’ effectiveness. The adoption of these evaluation criteria can further incentivize managers to exhibit brand-specific TFL. Second, given the strong mediation effect of employee sense of brand community, it is suggested that hospitality organizations pay special attention to the informal internal community in the organization as it may alter the effects of brand-specific TFL. Employee experiences in an internal community affect how they perceive their leaders in organizations. Therefore, cultivating and sustaining positive and close relationships with internal community leaders is critical for TFL effectiveness. In addition, it is critical for management to foster a supportive social environment where employees can experience a sense of belonging and obtain necessary skills and knowledge in order to excel at their roles. Brand-centered events, celebrations, and gatherings that strengthen employees’ social connections and exchanges are encouraged. As a result, employees are more likely to receive social and emotional support that is highly relevant to mitigate the demanding hospitality work environment. As a community, they are also more likely to develop a shared vision, a strong bond with other community members, as well as embody the brand values advocated by their leaders. This bonding force also aids the retention of employees. Further, the brand promise as shown in external brand communication is a controllable factor by organizations. Thus, it is critical to consider employees as an audience of external brand communications and carefully monitor their perceived accuracy of the brand promise. Although it is intuitive to not over-promise in advertisement to avoid customer disappointment, it is also important to depict a consistent look and feel of the brand image communicated to employees internally. In addition, as many external brand communication/promotion materials conveying the brand promise often feature employees, such communication should show reasonable expectations for employees. As such, employees are less likely to experience cognitive dissonance and more likely to deliver brand-aligned performance that is consistent with customer brand expectations (which is based on the brand promise). Limitations and future research There are a few limitations in this study that may be addressed in future research. First, considering the self-reported nature of this study, future studies are encouraged to collect data from multiple sources including manager reviews, employee insights, and/or customer evaluations on different constructs. In addition, as in many studies that examine social environments (e.g., a brand community) with ongoing exchanges among members, it would be beneficial to obtain longitudinal data to capture the continuous reciprocation among employees to gain more insights on the full dynamics the effects of brand-specific TFL. It is also interesting to examine whether the impact of brand-specific TFL differs based on an organization’s departments. As noted in Morhart et al. (2009), employees in sales department may be less influenced by TFL because of the goal-oriented mentality in generating sales. A second limitation of this study is generalizability in other cultural contexts. The data in this study were collected from a broad selection of US-based hospitality employees, however, the cultural characteristics of US organizations can be very different from those in other countries. For instance, Tse et al. (2013) suggested that the leader-member exchange mechanism might be more salient in an eastern cultural context with a higher power distance. Thus, variables that reflect culture characteristics should be included in future research as additional moderators that may affect transformational leadership’s effectiveness. Further, although employee investment-of-self in brand building is expected to propel their extra-role brand-aligned performance, this relationship is not assessed in this study. Future studies are encouraged to establish a nomological network of other typical internal branding outcomes (e.g., employee work engagement and brand identification) under brand-specific transformational leadership. Although this study applied multiple methods to control for common method bias such as the technique of including a theoretically unrelated marker variable (Lindell and Whitney 2001), it is important to note that partialling out the proxy marker variable method bias is inadequate to control for other sources of common method biases, such as social desirability and implicit theories (Podsakoff et al. 2003). The aforementioned suggestions such as longitudinal studies as well as cross-culture studies might be valuable remedies. Nevertheless, future studies are recommended to continue this effort to control for common method bias when data are self-reported. Last but not the least, the influence of external brand communication outside of organizations’ control on employees is largely unexplored in literature and needs future research attention. Although the general idea of achieving employees’ cognitive consonance should still hold based on this study, the extent to which such external brand communication from third-party sources (e.g., online travel agencies and news report) may further affect employees’ brand attitudes (e.g., brand belief and trust) is unclear and holds both theoretical and practical significance in IBM. Declarations Conflict of interest On behalf of all authors, the corresponding author states that there is no conflict of interest. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Aiken LS West SG Reno RR Multiple regression: Testing and interpreting interactions 1991 Sage Anderson JC Gerbing DW Structural equation modeling in practice: A review and recommended two-step approach Psychological Bulletin 1988 103 3 411 423 10.1037/0033-2909.103.3.411 Asatryan VS Oh H Psychological ownership theory: An exploratory application in the restaurant industry Journal of Hospitality and Tourism Research 2008 32 3 363 386 10.1177/1096348008317391 Avolio BJ Bass BM Jung DI Re-examining the components of transformational and transactional leadership using the Multifactor Leadership Journal of Occupational and Organizational Psychology 1999 72 4 441 462 10.1348/096317999166789 Avolio BJ Zhu W Koh W Bhatia P Transformational leadership and organizational commitment: Mediating role of psychological empowerment and moderating role of structural distance Journal of Organizational Behavior 2004 25 951 968 10.1002/job.283 Barros-Arrieta D García-Cali E Internal branding: Conceptualization from a literature review and opportunities for future research Journal of Brand Management 2021 28 2 133 151 10.1057/s41262-020-00219-1 Bass BM Leadership and performance beyond expectations 1985 New York Free Press Bernerth JB Aguinis H A critical review and best-practice recommendations for control variable usage Personnel Psychology 2016 69 1 229 283 10.1111/peps.12103 Braun S Peus C Weisweiler S Frey D Transformational leadership, job satisfaction, and team performance: A multilevel mediation model of trust The Leadership Quarterly 2013 24 1 270 283 10.1016/j.leaqua.2012.11.006 Brown G Pierce JL Crossley C Toward an understanding of the development of ownership feelings Journal of Organizational Behavior 2014 35 3 318 338 10.1002/job.1869 Brown ME Treviño LK Ethical leadership: A review and future directions The Leadership Quarterly 2006 17 6 595 616 10.1016/j.leaqua.2006.10.004 Buil I Martínez E Matute J From internal brand management to organizational citizenship behaviours: Evidence from frontline employees in the hotel industry Tourism Management 2016 57 256 271 10.1016/j.tourman.2016.06.009 Buil I Martínez E Matute J Transformational leadership and employee performance: The role of identification, engagement and proactive personality International Journal of Hospitality Management 2019 77 64 75 10.1016/j.ijhm.2018.06.014 Celsi MW Gilly MC Employees as internal audience: How advertising affects employees’ customer focus Journal of the Academy of Marketing Science 2010 38 4 520 529 10.1007/s11747-009-0173-x Chang A Chiang H-H Han T-S A multilevel investigation of relationships among brand-centered HRM, brand psychological ownership, brand citizenship behaviors, and customer satisfaction European Journal of Marketing 2012 46 5 626 662 10.1108/03090561211212458 Chiang HH Han TS McConville C D. A multilevel study of brand-specific transformational leadership: Employee and customer effects Journal of Brand Management 2020 27 3 312 327 10.1057/s41262-019-00182-6 Chun JU Cho K Sosik JJ A multilevel study of group-focused and individual-focused transformational leadership, social exchange relationships, and performance in teams Journal of Organizational Behavior 2016 37 3 374 396 10.1002/job.2048 Coelho FJ Lages CR Sousa CM Personality and the creativity of frontline service employees: Linear and curvilinear effects The International Journal of Human Resource Management 2018 29 17 2580 2607 10.1080/09585192.2016.1255982 Coy, J. 2006. Shrinking Labor Force is Top Challenge for Global Hospitality, Tourism and Service Industries. ISHC Top, 10. Crossley CD Bennett RJ Jex SM Burnfield JL Development of a global measure of job embeddedness and integration into a traditional model of voluntary turnover Journal of Applied Psychology 2007 92 4 1031 1042 10.1037/0021-9010.92.4.1031 17638463 Eberly MB Bluhm DJ Guarana C Avolio BJ Hannah ST Staying after the storm: How transformational leadership relates to follower turnover intentions in extreme contexts Journal of Vocational Behavior 2017 102 72 85 10.1016/j.jvb.2017.07.004 Festinger L A theory of cognitive dissonance 1957 Stanford, CA Stanford University Press Fornell CR Larcker DF Structural equation models with unobserved variables and measurement error: Algebra and statistics Journal of Marketing Research 1981 18 3 382 388 10.1177/002224378101800313 Hair JF Black WC Babin BJ Anderson RE Tatham RL Multivariate data analysis 2006 Pearson Prentice Hall Harmon-Jones, E., and Mills, J. 2019. An introduction to cognitive dissonance theory and an overview of current perspectives on the theory. Henseler J Ringle CM Sarstedt M A new criterion for assessing discriminant validity in variance-based structural equation modeling Journal of the Academy of Marketing Science 2015 43 1 115 135 10.1007/s11747-014-0403-8 Herman HM Huang X Lam W Why does transformational leadership matter for employee turnover? A multi-foci social exchange perspective The Leadership Quarterly 2013 24 5 763 776 10.1016/j.leaqua.2013.07.005 Hinojosa AS Gardner WL Walker HJ Cogliser C Gullifor D A review of cognitive dissonance theory in management research: Opportunities for further development Journal of Management 2017 43 1 170 199 10.1177/0149206316668236 Iacobucci D Structural equations modeling: Fit indices, sample size, and advanced topics Journal of Consumer Psychology 2010 20 1 90 98 10.1016/j.jcps.2009.09.003 Jaiswal NK Dhar RL Transformational leadership, innovation climate, creative self-efficacy and employee creativity: A multilevel study International Journal of Hospitality Management 2015 51 30 41 10.1016/j.ijhm.2015.07.002 Karatepe OM Perceived organizational support, career satisfaction, and performance outcomes: A study of hotel employees in Cameroon International Journal of Contemporary Hospitality Management 2012 24 5 735 752 10.1108/09596111211237273 Katz, E., and Paul, F. 1955. Lazarsfeld. 1955. Personal Influence: The part played by people in the Flow of Mass communications. Glencoe, Illinois: The Free Press. KatzPersonal Influence: The Part Played by People in the Flow of Mass Communication. King C Grace D Exploring managers’ perspectives of the impact of brandmanagement strategies on employee roles within a service firm Journal of Services Marketing 2006 20 6 369 380 10.1108/08876040610691266 King C Grace D Employee based brand equity: A third perspective Services Marketing Quarterly 2009 30 122 147 10.1080/15332960802619082 Leonhardt, M. 2021. The Great Resignation is Hitting These Industries Hardest. https://fortune.com/2021/11/16/great-resignation-hitting-these-industries-hardest/. Liaw YJ Chi NW Chuang A Examining the mechanisms linking transformational leadership, employee customer orientation, and service performance: The mediating roles of perceived supervisor and coworker support Journal of Business and Psychology 2010 25 3 477 492 10.1007/s10869-009-9145-x Lievens F Highhouse S The relation of instrumental and symbolic attributes to a company's attractiveness as an employer Personnel Psychology 2003 56 1 75 102 10.1111/j.1744-6570.2003.tb00144.x Lindell MK Whitney DJ Accounting for common method variance in cross-sectional research designs Journal of Applied Psychology 2001 86 1 114 10.1037/0021-9010.86.1.114 11302223 Liu, J., and Cho, S. 2018. Interaction effect of display rules and emotional intelligence on hotel managers’ and non-managers’ work engagement. International Journal of Contemporary Hospitality Management. MacKenzie SB Podsakoff PM Common method bias in marketing: Causes, mechanisms, and procedural remedies Journal of Retailing 2012 88 4 542 555 10.1016/j.jretai.2012.08.001 MacKinnon DP Lockwood CM Williams J Confidence limits for the indirect effect: Distribution of the product and resampling methods Multivariate Behavioral Research 2004 39 1 99 128 10.1207/s15327906mbr3901_4 20157642 McMillan DW Chavis DM Sense of community: A definition and theory Journal of Community Psychology 1986 14 1 6 23 10.1002/1520-6629(198601)14:1<6::AID-JCOP2290140103>3.0.CO;2-I Miles SJ Mangold G A conceptualization of the employee branding process Journal of Relationship Marketing 2004 3 2–3 65 87 10.1300/J366v03n02_05 Mitchell TR Holtom BC Lee TW How to keep your best employees: Developing an effective retention policy Academy of Management Perspectives 2001 15 4 96 108 10.5465/ame.2001.5897929 Moreland, R.L., J.M. Levine, and J.G. McMinn. 2001. Self-categorization and work group socialization. Social Identity Processes in Organizational Contexts, 87–100. Morhart FM Herzog W Tomczak T Brand-specific leadership: Turning employees into brand champions Journal of Marketing 2009 73 122 142 10.1509/jmkg.73.5.122 Murillo E King C Why do employees respond to hospitality talent management International Journal of Contemporary Hospitality Management. 2019 31 10 4021 4042 10.1108/IJCHM-10-2018-0871 Park TY Shaw JD Turnover rates and organizational performance: A meta-analysis Journal of Applied Psychology 2013 98 2 268 10.1037/a0030723 23244224 Pearlman DM Schaffer JD Labor issues within the hospitality and tourism industry: A study of Louisiana's attempted solutions Journal of Human Resources in Hospitality and Tourism 2013 12 3 217 242 10.1080/15332845.2013.769131 Piehler R Schade M Burmann C Employees as a second audience: The effect of external communication on internal brand management outcomes Journal of Brand Management 2019 26 4 445 460 10.1057/s41262-018-0135-z Pierce JL Kostova T Dirks KT Toward a theory of psychological ownership in organizations Academy of Management Review 2001 26 2 298 310 10.2307/259124 Pierce JL Kostova T Dirks KT The state of psychological ownership: Integrating and extending a century of research Review of General Psychology 2003 7 1 84 107 10.1037/1089-2680.7.1.84 Pieterse AN Van Knippenberg D Schippers M Stam D Transformational and transactional leadership and innovative behavior: The moderating role of psychological empowerment Journal of Organizational Behavior 2010 31 4 609 623 10.1002/job.650 Podsakoff PM MacKenzie SB Lee JY Podsakoff NP Common method biases in behavioral research: A critical review of the literature and recommended remedies Journal of Applied Psychology 2003 88 5 879 903 10.1037/0021-9010.88.5.879 14516251 Powell SM Journal of Brand Management: Year end review 2020 Journal of Brand Management 2020 27 6 623 628 10.1057/s41262-020-00209-3 Reynolds KE Arnold MJ Customer loyalty to the salesperson and the store: Examining relationship customers in an upscale retail context Journal of Personal Selling and Sales Management 2000 20 2 89 98 Rogelberg SG Stanton JM Introduction: Understanding and dealing with organizational survey nonresponse Organizational Research Methods 2007 10 2 195 209 10.1177/1094428106294693 Ronda L Valor C Abril C Are they willing to work for you? An employee-centric view to employer brand attractiveness Journal of Product and Brand Management. 2018 27 5 573 596 10.1108/JPBM-07-2017-1522 Rosenbaum MS Ramirez GC Reconsidering services marketing as a discipline Journal of Global Hospitality and Tourism 2022 1 1 85 87 10.5038/2771-5957.1.1.1005 Sampson, Hannah. “Southwest’s plan to conquer the airline industry, one joke at a time.” Washingtonpost.com, 16 October 2019. https://www.washingtonpost.com/travel/2019/10/16/southwests-plan-conquer-airline-industry-one-joke-time/. Accessed 1 Mar 2021. Seriki OK Evans KR Jeon HJJ Dant RP Helm A Unintended effects of marketing messages on salespeople’s cynicism European Journal of Marketing 2016 50 5/6 1047-1-72 10.1108/EJM-07-2014-0440 De Smet, A., B. Dowling, M. Mugayar-Baldocchi, and B. Schaninger (2021). ‘Great Attrition’ or ‘Great Attraction’? The choice is yours. McKinsey Quarterly. https://www.mckinsey.com/business-functions/people-and-organizational-performance/our-insights/great-attrition-or-great-attraction-the-choice-is-yours. Tse HHM Huang X Lam W Why does transformational leadership matter for employee turnover? A multi-foci social exchange perspective The Leadership Quarterly 2013 24 5 763 776 10.1016/j.leaqua.2013.07.005 U.S. Bureau of Labor Statistics. 2021. Economic News Release. https://www.bls.gov/news.release/jolts.t04.htm#jolts_table4.f.p. Uen JF Wu T Teng HC Liu YS Transformational leadership and branding behavior in Taiwanese hotels International Journal of Contemporary Hospitality Management. 2012 24 1 26 43 10.1108/09596111211197782 Watts DJ Dodds PS Influentials, networks, and public opinion formation Journal of Consumer Research 2007 34 4 441 458 10.1086/518527 Wenger, E. 2011. Communities of practice: A brief introduction. https://scholarsbank.uoregon.edu/xmlui/bitstream/handle/1794/11736/A%20brief%20introduction%20to%20CoP.pdf?sequence=1andisAllowed=y. Wenger EC Snyder WM Communities of practice: The organizational frontier Harvard Business Review 2000 78 1 139 146 11184968 Xiong L King C Motivational drivers that fuel employees to champion the hospitality brand International Journal of Hospitality Management 2015 44 58 69 10.1016/j.ijhm.2014.10.009 Xiong L King C Too much of a good thing? Examining how proactive personality affects employee brand performance under formal and informal organizational support International Journal of Hospitality Management 2018 68 12 22 10.1016/j.ijhm.2017.09.007 Xiong L King C Aligning employees’ attitudes and behavior with hospitality brands: The role of employee brand internalization Journal of Hospitality and Tourism Management 2019 40 67 76 10.1016/j.jhtm.2019.06.006 Xiong L King C Exploring how employee sense of brand community affects their attitudes and behavior Journal of Hospitality and Tourism Research 2020 44 4 567 596 10.1177/1096348020905360 Xiong L King C Piehler R “That's not my job”: Exploring the employee perspective in the development of brand ambassadors International Journal of Hospitality Management 2013 35 348 359 10.1016/j.ijhm.2013.07.009 Xiong L So KKF Wu L King C Speaking up because it’s my brand: Examining employee brand psychological ownership and voice behavior in hospitality organizations International Journal of Hospitality Management 2019 83 274 282 10.1016/j.ijhm.2018.11.006 Zhao X Lynch JG Jr Chen Q Reconsidering Baron and Kenny: Myths and truths about mediation analysis Journal of Consumer Research 2010 37 2 197 206 10.1086/651257
PMC009xxxxxx/PMC9824953.txt	==== Front Environ Int Environ Int Environment International 0160-4120 1873-6750 The Authors. Published by Elsevier Ltd. S0160-4120(23)00016-8 10.1016/j.envint.2023.107743 107743 Full Length Article Wastewater-based prediction of COVID-19 cases using a highly sensitive SARS-CoV-2 RNA detection method combined with mathematical modeling Ando Hiroki a Murakami Michio b Ahmed Warish c Iwamoto Ryo de Okabe Satoshi a Kitajima Masaaki a⁎ a Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan b Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan c CSIRO Environment, Ecosciences Precinct, 41 Boggo Road, QLD 4102, Australia d Shionogi & Co. Ltd, 1-8, Doshomachi 3-Chome, Chuo-ku, Osaka, Osaka 541-0045, Japan e AdvanSentinel Inc, 1-8 Doshomachi 3-Chome, Chuo-ku, Osaka, Osaka 541-0045, Japan ⁎ Corresponding author. 7 1 2023 3 2023 7 1 2023 173 107743107743 2 11 2022 6 1 2023 6 1 2023 © 2023 The Authors 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Graphical abstract Wastewater-based epidemiology (WBE) has the potential to predict COVID-19 cases; however, reliable methods for tracking SARS-CoV-2 RNA concentrations (CRNA) in wastewater are lacking. In the present study, we developed a highly sensitive method (EPISENS-M) employing adsorption-extraction, followed by one-step RT-Preamp and qPCR. The EPISENS-M allowed SARS-CoV-2 RNA detection from wastewater at 50 % detection rate when newly reported COVID-19 cases exceed 0.69/100,000 inhabitants in a sewer catchment. Using the EPISENS-M, a longitudinal WBE study was conducted between 28 May 2020 and 16 June 2022 in Sapporo City, Japan, revealing a strong correlation (Pearson’s r = 0.94) between CRNA and the newly COVID-19 cases reported by intensive clinical surveillance. Based on this dataset, a mathematical model was developed based on viral shedding dynamics to estimate the newly reported cases using CRNA data and recent clinical data prior to sampling day. This developed model succeeded in predicting the cumulative number of newly reported cases after 5 days of sampling day within a factor of √2 and 2 with a precision of 36 % (16/44) and 64 % (28/44), respectively. By applying this model framework, another estimation mode was developed without the recent clinical data, which successfully predicted the number of COVID-19 cases for the succeeding 5 days within a factor of √2 and 2 with a precision of 39 % (17/44) and 66 % (29/44), respectively. These results demonstrated that the EPISENS-M method combined with the mathematical model can be a powerful tool for predicting COVID-19 cases, especially in the absence of intensive clinical surveillance. Keywords Wastewater-based epidemiology SARS-CoV-2 COVID-19 Quantification method EPISENS-M Mathematical model Handling Editor: Thanh Nguyen ==== Body pmc1 Introduction COVID-19 has been monitored for tailoring infection control policy based on the severity of its prevalence. Clinical surveillance of coronavirus disease (COVID-19) tends to overlook asymptomatic and mildly symptomatic individuals who do not seek medical care, whereas environmental surveillance is a cost-effective approach for obtaining population-level and near real-time epidemiological information. Recently, wastewater-based epidemiology (WBE) has garnered attention as a powerful tool to predict the prevalence of COVID-19 in a sewer catchment (Kitajima et al., 2020), as infected individuals, including those who are asymptomatic, shed the viruses into the sewer system via human excreta (Lavania, 2022, Park, 2021) and bodily fluids (e.g., saliva, nasal secretions) before developing symptoms (Gudbjartsson, 2020, Gandhi et al., 2020). Prediction of the prevalence through WBE is pivotal for decision-makers to prepare for imminent epidemics, especially in the absence of fully notifiable clinical surveillance. Numerous studies have attempted to estimate the COVID-19 prevalence or predict the subsequent outbreaks in a catchment via WBE using multiple regression models (Tiwari, 2022, Zulli, 2022), infectious mathematical models (Nourbakhsh et al., 2022), or artificial intelligence (Jiang et al., 2022). Although previous studies have reported the potential of WBE as a 1- to 10-day leading indicator of clinically reported cases (Peccia, 2020, Wu, 2022), the validated framework remains untested to estimate the number of infected individuals from SARS-CoV-2 RNA concentrations (C RNA) in wastewater. This is mainly because most of the previously reported models did not consider the viral shedding dynamics of COVID-19 patients (Jiang, 2022, Saththasivam, 2021) who excrete SARS-CoV-2 for over 20 days at fluctuating concentrations, even after negative respiratory tract sample (Miura et al., 2021). Furthermore, the performance of the proposed predictive models has not been thoroughly validated (Deaver, 2021, Nourbakhsh, 2022). Although the relationship between C RNA and clinically reported cases might vary between infection surges due to vaccination intake proportion and/or emerging variants that change asymptomatic ratio and the amount of viral shedding, only single infection surge data was used for model testing (Deaver, 2021, Nourbakhsh, 2022). Hence, it is important to develop a mathematical model that considers viral shedding dynamics and is validated with longitudinal data, including several infection surges, for predicting COVID-19 cases in communities. Longitudinal tracking of C RNA requires a highly sensitive method that allows for the quantification of viral RNA in wastewater collected even in low-prevalence settings. Recently, we developed a highly sensitive method for SARS-CoV-2 RNA detection in wastewater called the EPISENS-S method, which consists of pelleting wastewater samples with low-speed centrifugation, followed by RNA extraction from the pellet, RT-preamplification, and qPCR analysis (Ando et al., 2022). However, pelleting of samples was not always effective, especially for diluted wastewater. An adsorption-extraction method using an electronegative membrane has been shown to capture SARS-CoV-2 in wastewater with high efficiency (Ahmed, 2020a, Barua, 2022, Haramoto et al., 2020). Therefore, we postulated that electronegative membrane filtration might be a superior alternative to pelleting in the EPISENS-S method for concentrating SARS-CoV-2 from wastewater samples containing small amount of solid. In the present study, we aimed to establish a framework for predicting the number of cases from C RNA. To accomplish this, we first developed a highly sensitive method for longitudinal tracking of C RNA. This method employed a simple protocol consisting of electronegative membrane filtration, direct RNA extraction from the membrane, and one-step RT-preamplification prior to qPCR, named the Efficient and Practical Virus Identification System with Enhanced Sensitivity for Membrane (hereafter referred to as EPISENS-M). This method allowed for the efficient recovery and quantification of pepper mild mottle virus (PMMoV), which is used to as a fecal strength indicator (Kitajima et al., 2018) and normalizer of the C RNA (Kim et al., 2022). Subsequently, we developed a mathematical model based on viral shedding dynamics using longitudinal WBE data, allowing for the prediction of COVID-19 cases solely from C RNA, which was successfully validated against 2-year new COVID-19 cases reported by fully notifiable clinical surveillance. 2 Materials and methods 2.1 Wastewater sampling Between May 28, 2020 and June 16, 2022, a total of 207 untreated grab wastewater samples were collected at around 10 am weekly from two WWTPs (104 samples from WWTP A and 103 samples from WWTP B) serving roughly 20 % of the population in Sapporo City (1.96 million inhabitants), Japan, whose age distributions are shown in Fig. S1 in the supplementary material. The catchments of the two WWTPs utilize combined sewer systems. The wastewater samples were collected in sterile plastic bottles and immediately transported to the laboratory on ice. The samples were processed within 24 h after collection. The minimum recommended meta-information on wastewater samples is summarized in Table S1. 2.2 The EPISENS-M method 2.2.1 Method description The EPISENS-M method was developed by modifying the EPISENS-S method (Ando et al., 2022). The method is characterized by electronegative membrane filtration capturing viruses in solid and liquid fractions of influent wastewater and direct RNA extraction from the membrane (adsorption-extraction), instead of low-speed centrifugation pelleting, followed by direct RNA extraction from pellets used in the EPISENS-S method (Fig. 1 A). The EPISENS-M method consists of adsorption-extraction, followed by one-step RT-Preamp and qPCR. The theoretical limit of detection (LOD) of the EPISENS-M method is 49.3 copies/L under the assumption that the recovery efficiency of viral RNA for the whole process is 100 %.Fig. 1 (A) Detection flow of the EPISENS-M method and the EPISENS-S method. (B) Comparison of the EPISENS-M and EPISENS-S methods. Red circles and blue triangles denote observed SARS-CoV-2 RNA and PMMoV RNA concentrations in influent wastewater, respectively (n = 37). The EPISENS-M method exhibits higher recovery of PMMoV RNA (p < 1.0 × 10-9, Cohen’s d = 1.56, paired t-test; n = 37), but comparable recovery of SARS-CoV-2 RNA (p = 0.98, Cohen’s d = 0.004, paired t-test; n = 34, quantified samples used) as compared to the EPISENS-S method. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) 2.2.2 Filtration and RNA extraction Wastewater samples were subjected to adsorption-extraction methods (Ahmed, 2020a, Ahmed, 2020b) with slight modifications of buffer composition in the bead beating process. Briefly, 300 mL of untreated wastewater was supplemented with a final concentration of 25 mM MgCl2, which was then filtrated through an electronegative mixed cellulose-ester membrane (AAWP09000; pore size, 0.8 μm; diameter, 90 mm; Merck Millipore, Burlington, MA, USA). A quarter of the membrane was inserted into a 5-mL PowerWater bead tube of the RNeasy PowerWater Kit (Qiagen, Hilden, Germany) containing 850 μL of PM1, 150 μL of TRIzol Reagent (Life Technologies, Carlsbad, CA, USA), and 10 μL of β-Mercaptoethanol (Wako, Osaka, Japan). Addition of TRIzol Reagent to the PM1 buffer could improve SARS-CoV-2 recovery efficiency from wastewater samples (Table S2). The bead beating was conducted using a Precellys 24 tissue homogenizer (Bertin Technologies, Montigny-le-Bretonneux, France) under the following conditions: 3 × 20 s at 10,000 rpm and at 15 s intervals. 450 μL of the sample lysate from the bead beating tube was transferred to a rotor adapter (Qiagen) using a QIAcube Connect platform and the RNeasy PowerMicrobiome Kit (Qiagen) to obtain 50 μL of RNA extract. 2.2.3 One-step RT-Preamp and qPCR One-step reverse transcription (RT)-preamplification and qPCR were performed according to a previous study (Ando et al., 2022). Briefly, 13.5 μL of the RNA extract was subjected to the RT-Preamp step using the iScriptTM Explore One-step PreAmp Kit (Bio-Rad Laboratories, Hercules, CA, USA) to obtain 30 μL of RT-preamp product. A tenfold serial dilution of plasmid DNA containing the amplification region sequence of the qPCR assay (CDC N1, Integrated DNA Technologies, Coralville, IA, USA) was included to generate a standard curve at concentrations ranging from 105 to 100 copies/ RT-Preamp reaction. Nuclease-free water was used as a negative control in the RT-Preamp reaction. qPCR for SARS-CoV-2 and PMMoV was performed in a total reaction volume of 25 μL containing 2.5 μL of the RT-Preamp product, using each primer/probe set (Table S3). Tenfold serial dilutions of gBlocks for PMMoV (101 to 105 copies/reaction) suspended in molecular-grade water were used for the quantification of viral copy numbers in the PCR tubes. The slope and Y-intercept of the preamp–qPCR standard curve for SARS-CoV-2 were -3.23 and 32.4, respectively. The slope and Y-intercept of the qPCR standard curve for PMMoV were -3.38 and 40.2, respectively. The MIQE (Minimum Information for Publication of Quantitative Real-Time PCR Experiments) checklist was provided as supplementary material (Table S4). 2.3 The EPISENS-S method The EPISENS-S method was conducted according to our recent report (Ando et al., 2022) (Fig. 1 A). Briefly, 40 mL of influent wastewater was centrifuged at 10,000 g for 10 min to collect wastewater solids as pellets. The supernatant was removed completely by decanting, and the resultant pellet was subjected to RNA extraction. Total RNA in the pellet was extracted using the RNeasy PowerMicrobiome Kit (Qiagen, Hilden, Germany) to obtain a final RNA extract of 50 μL, according to the manufacturer’s instructions. One-step RT-preamplification and qPCR for SARS-CoV-2 and PMMoV were performed as described above. 2.4 Examination of the capture efficiency of membrane filtration A 300 mL of influent wastewater sample collected on May 24, 2022 from WWTP B. A 500 mL of MilliQ water was seeded with heat-inactivated SARS-CoV-2 (ATCC VR-1986HK) and murine hepatitis virus (MHV) as a whole process control (WPC) to obtain the final concentration of 1.12 × 105 copies/L and 4.34 × 105copies/L, respectively. The seeded wastewater samples were supplemented with MgCl2 to obtain a final concentration of 25 mM and filtered through the electronegative membrane. Thereafter, the filtered wastewater samples supplemented with 25 mM MgCl2 and 4.34 × 105 copies of MHV were passed through a second electronegative membrane. Both membranes inoculated with murine norovirus (MNV) as a molecular process control (MPC) were subjected to the detection of SARS-CoV-2 RNA with EPISENS-M, as mentioned above. The primer mixture in RT-Preamp and primer/probe sets for MHV and MNV are shown in Tables S3 and S5. The RT-Preamp reaction for MHV and MNV is the same as that for CDC N1. The qPCR reaction for MHV and MNV was performed under the following conditions: 50 °C for 2 min and initial denaturation at 95 °C for 10 min to activate the DNA polymerase, followed by 45 cycles of denaturation at 95 °C for 15 s and annealing and extension at 60 °C for 60 s. The SARS-CoV-2 capture efficiency of membrane filtration was calculated based on the copy numbers quantified by RT-qPCR as follows:CaptureEfficiency%=(1-RNAcopiesrecoveredfromsecondmembraneRNAcopiesrecoveredfromfirstmembrane)×100 2.5 Logistic regression model A logistic regression model was used to estimate the detection probability of the EPISENS-M method for SARS-CoV-2 RNA from wastewater when a certain number of newly reported COVID-19 cases/ 100,000 people in Sapporo are reported. The logistic regression model is expressed as the following equation:LogP1-P=β1+β2×A where P represents the detection probability, A represents the 7-day central moving average of daily clinical confirmed cases in Sapporo City, and β1andβ2 are parameters. To estimate the parameters in the model, the detection results of SARS-CoV-2 RNA from wastewater were transformed into binary data (positive or negative). In this study, P = 1.0 was assumed to be only the case when SARS-CoV-2 RNA was detected from wastewater collected at two WWTPs in the same week. All statistical analyses were performed in R Statistical Computing Software version 4.1.2 (R) and the code is shown in the Supplementary material. 2.6 Development of mathematical model for reported case prediction A mathematical model, named "PRedictive Estimation of cases with Sewage-based ENhanced Surveillance (PRESENS) model", was developed based on the mass balance between SARS-CoV-2 RNA shed from infected individuals that enters WWTPs in a city. The PRESENS model consists of viral shedding dynamics of the infected, newly reported COVID-19 cases, and several constant values, described in Equation (1):(1) Lt0=F×fQ×(1-AS)∑t=X-24XI(t0+t)×C-t+X where t0 is a day in which wastewater sampling is conducted, L(t0) is SARS-CoV-2 RNA concentration in influent wastewater (C RNA, copies/L,), F is the daily amount of feces of an individual in developed countries (128 g-feces/person/day) (Rose et al., 2015); Q is the flow rate in Sapporo (109 L/day), f is the proportion of infected persons who shed SARS-CoV-2 RNA in their feces (0.5) (Lavania, 2022, Mauro, 2022, Twigg and Wenk, 2022, Zhang, 2021, Parasa, et al., 2019), and AS is the proportion of asymptomatic infections (0.35) (Ma, 2021, Oran and Topol, 2020, Alene, et al., 2021). The values of f and AS were referred to in previous reports summarized in Table S6. In the sigma function, X is the time lag (day) between onset of shedding viruses into WWTP considering transportation time in sewage pipeline and being reported by clinical surveillance. I(t0 + t) refers to newly reported cases (persons) t days after sampling day, as obtained from the website of the Sapporo City Health Center (https://ckan.pf-sapporo.jp/dataset/covid_19_patients). C(t) is the concentration of SARS-CoV-2 RNA in feces (copies/g-feces) on t day of virus shedding. The virus shedding dynamics C(t) is referred to in previous studies ((Miura et al., 2021, Teunis, 2015)), following Equation (2):(2) Ctα,β,C0=C0e-αt1-e-β-αtα<β C0 = Aα/(β-α), Where A is the initial concentration of viruses and α and β are transport rates of viruses. At the onset of shedding (t = 0), the virus concentration is 0. The infected ones shed viruses into their feces for over 20 days even after respiratory tracts test negative (Miura et al., 2021, Wu, et al., 2020). In the present study, it was assumed that viral excretion continues until the 24th day of viral shedding. 2.7 Estimation of parameters in the model The four parameters (A, α, β, X) in the model were determined by assuming maximum likelihood under the assumption that error follows normal distribution, i.e., the least-squares method (Wu et al., 2022). A total of 38 datasets concerning the geometric concentration in wastewater in two WWTPs in the same week and newly reported COVID-19 cases in Sapporo from 16 October 2020 to 16 June 2021 were provided for parameter estimation. These datasets were obtained when two infectious surges occurred in Sapporo. Before 15 October 2020, SARS-CoV-2 RNA was not detected at the two WWTPs in the same week; thus, the wastewater-based data was not used for parameter estimation. It was assumed that the observed C RNA in two WWTPs can be subjected to direct calculation of geometric means, for the catchment population and geometric PMMoV (i.e., fecal strength indicator) concentrations in each WWTP are almost the same. In the case of C RNA normalized by PMMoV, the C RNA was divided by the PMMoV concentration in the same sample and multiplied by the geometric mean PMMoV concentrations in each WTTP. The observed concentrations (L1.i) and estimated concentrations (L2.i) based on the model and reported cases were converted to logarithms (log10 copies/L) followed by parameter determination to minimize the sum of squared errors (SSE) (Equation (3)), as follows:(3) SSE=∑i=138(L1.i-L2.i)2 The parameter fitting was conducted in the Monte Carlo simulation under the conditions that simulation consists of 5,000 iterations and the ranges of A, α, B, X are [107, 1011], [0.01, 5], [3, 20]( [0, 10], respectively. Initial parameter sets (A, α, B, X: (1) [107, 0.01, 3, 0], (2) [1011, 5, 20, 10], and (3) [109, 0.9, 4.5, 6]) were used to create a variety of starting shapes for the shedding function. The parameter determination was performed using the Oracle Crystal Ball software (Oracle, California, USA) combined with Microsoft Excel. The Excel file for the parameter estimation was provided as Supplementary material. 2.8 Estimation of the newly reported case in Sapporo City A total of 44 wastewaterand clinical datasets between 24 July 2021, and 16 June 2022 were used for the validation of estimating the newly reported cases in Sapporo via WBE. These datasets include infectious surges from 24 July to October 2021 and from January to June 2022 in Sapporo City. When SARS-CoV-2 RNA was not detected, C RNA was assumed to be the square root of the LOD of the EPISENS-M method (7.03 copies/L). The total of reported cases in Sapporo one day after sampling to X-1 (delay in clinical reporting) days after sampling day (s) (IE(s)) was estimated, following the two equations (Equations (4), (5)) that are based on the back calculation of Equation (1) and a proximity formula (Supplemental Materials). Equation (4) employs observed C RNA (L(t)) and newly reported COVID-19 cases reported by clinical surveillance (I(t)), while Equation (5) uses the number of newly reported COVID-19 cases estimated from observed C RNA so far (Ie(t)), instead of recent clinical data. Thus, equation (5) allows for estimating the number of newly reported cases without the recent results of clinical surveillance. In the present study, the number of COVID-19 cases on X days after the sampling day cannot be calculated because the concentration in feces C(0) is 0:(4) IE(t0)=∑t=1X-1Iet0+t≅1A×(Lt0K-∑t=X-240It0+t×C-t+X) (5) IE(tint+n)=∑t=1X-1Ie((tint+n)+t)≅1A×(L(tint+n)K-∑t=X-240Ie((tint+n)+t)×C(-t+X))Ie((tint+n)+1)=1X-1IE(tint+n)(n=0,1,2,..N(studyduration)) A=1X-1∑t=1X-1CX,K=F×fQ×1-AS where tint is defined as the start date of wastewater sampling (28 May 2020) in this study. Ie (tint + n) is the estimated number of newly reported COVID-19 cases n days after tint from the measured C RNA. The estimated cases before wastewater sampling began (Ie (X-24) to Ie (0)) were assumed to be the same as the newly confirmed cases reported by clinical surveillance. The C RNA on days (L (tint + n)) for which there were no data were regarded as the same as the C RNA measured on the preceding closest day. The confidence intervals were not defined because the proximity formula was used in the estimation of future reported cases, and the appropriate distribution of errors of estimating cases cannot be found. Instead, the range of estimation based on the distance from the median was provided for evaluating the accuracy of the developed model. We proposed ranges within as a factor √2 and 2 estimated values, since the number of infected individuals with SARS-CoV-2 is expected to fluctuate exponentially. 3 Results 3.1 Development of the EPISENS-M method The development of the EPISENS-M method began with the confirmation that SARS-CoV-2 could be adsorbed to electronegative membrane with adequately high efficiencies (>95 %) for both influent wastewater and MilliQ water (i.e., ultrapure water) in the presence of MgCl2 (Table S7). To validate the newly developed EPISENS-M method to detect viral RNA from influent wastewater in comparison with the previously developed EPISENS-S method, we determined C RNA and PMMoV RNA concentrations in 37 influent wastewater samples collected at two WWTPs between 3 March 2021 and 2 June 2021 using both methods (Fig. 1 A, B). PMMoV RNA was detected in all samples at concentrations of 1.25 × 108 (range: 5.43 × 107 to 2.94 × 108; n = 37) and 5.05 ×107 (range: 2.60 × 106 to 1.90 × 108; n = 37) copies/L determined by the EPISENS-M method and EPISENS-S method, respectively (Fig. 1 B). The concentrations of PMMoV RNA determined by the EPISENS-M method were significantly greater than those determined by the EPISENS-S method (p < 1.0 × 10-9, Cohen’s d = 1.56, paired t-test; n = 37). The positive ratios for SARS-CoV-2 with the EPISENS-M method and the EPISENS-S method were 100 % (37/37) and 91.9 % (34/37), respectively. The observed C RNA determined by the EPISENS-M method and EPISENS-S method were 1.98 × 103 (range, 1.13 × 102 to 4.10 × 104; n = 37) and 2.39 × 103 (range, 1.31 × 102 to 3.85 × 104; n = 34), respectively, showing no significant difference between the two methods for the same sample set (p = 0.98, Cohen’s d = 0.004, paired t-test; 34 positive samples for the analysis). 3.2 Longitudinal monitoring of SARS-CoV-2 RNA in wastewater using the EPISENS-M method To track the dynamics of C RNA in response to COVID-19 incidence, we collected influent wastewater from two wastewater treatment plants (WWTPs) (WWTP A and B) weekly from 28 May 2020 to 16 June 2022. We then processed the samples (n = 207) with the EPISENS-M method. The service population of the two WWTPs, both of which are connected to combined sewer systems, is approximately 10 % each of the total population of Sapporo, a city with a population of 1.96 million. PMMoV was also quantified for all wastewater samples as a fecal strength indicator to normalize C RNA. PMMoV RNA was detected in all wastewater samples from WWTP A and B with mean concentrations of 8.12 × 107 (range, 1.77 × 107 to 3.68 × 108; n = 104) and 8.21 × 107 (range, 1.61 × 107 to 3.17 × 108; n = 103) copies/L, respectively (Fig. 2 A). The PMMoV RNA concentrations were relatively stable regardless of season ( Fig. 2 A, S2A).Fig. 2 (A) The dynamics of viral RNA concentrations in influent wastewater and newly reported COVID-19 cases/100,000 inhabitants in Sapporo between May 28, 2020 and June 16, 2022. The circle plots denote SARS-CoV-2 RNA concentrations in wastewater (CRNA) and the triangle plots denote PMMoV RNA concentrations in wastewater collected at two WWTPs. The red and blue lines denote geometric means of CRNA and PMMoV RNA concentrations, respectively. In Sapporo, less stringent countermeasures, such as declaration of a state of emergency and pre-emergency measures, were practiced three times during the study period (i.e., April 14 to May 31, 2020; May 9 to June 11, 2021; August 2 to September 30, 2021) (B) Comparison of Pearson’s r values with and without normalization by PMMoV. The blue vertical bars denote the correlation coefficients between the 7-day moving average of newly reported cases and CRNA without normalization, while the gray vertical bars represent the concentration with normalization by PMMoV. Time lag refers to the difference between the sampling day and the day set as the center date of the 7-day moving average. PMMoV normalization did not improve the value of Pearson’s r. The CRNA without normalization showed the highest value of Pearson’s r with the 7-day moving average centered four days after the sampling day. (C) Correlation of the CRNA and newly reported COVID-19 cases/ 100,000 inhabitants in Sapporo. SARS-CoV-2 RNA concentration in the Y-axis refers to the geometric CRNA at two WWTPs in the same week. Newly reported COVID-19 cases on the X-axis are made up of the 7-day moving average centered on the 4-day after sampling day (Pearson’s r = 0.94, p < 1.0 × 10-10, quantified sample used n = 76). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) SARS-CoV-2 RNA was detected in 163 (83.6 %) out of 195 influent wastewater samples, and 76 pairs of samples collected from two WWTPs in the same week tested positive for SARS-CoV-2. Non-detects were observed from 28 May 2020 to 14 October 2020, and from 27 September 2021 to 4 January 2022, when the daily clinical confirmed cases numbered<1.7/100,000 inhabitants in Sapporo City (Fig. 2 A). Non detections were not always observed when less stringent countermeasures, such as declaration of a state of emergency and pre-emergency measures, were practiced three times during the study period (i.e., April 14 to May 31, 2020; May 9 to June 11, 2021; August 2 to September 30, 2021) in the city. The C RNA showed the highest correlation efficiency with the 7-day moving average centered 4 days after the sampling days of newly reported cases in the city (Pearson’s r = 0.94, p < 1.0 × 10-10, only quantifiable samples used) (Fig. 2 B, 2C). We also observed that normalization with PMMoV did not improve the correlation efficiency (Pearson’s r = 0.93, p < 1.0 × 10-10, only quantifiable samples used) (Fig. 2 C, S2B). 3.3 Sensitivity of the EPISENS-M method To estimate the COVID-19 incidence levels required for the EPISENS-M method to detect SARS-CoV-2 RNA from influent wastewater, the longitudinal wastewater data described above were analyzed using a logistic regression model. As shown in Fig. 3 A, the parameters of β1 and β2 in the logistic model were estimated to be − 2.75 (95 % CI: −4.52 to − 1.41, p < 0.0005) and 4.01 (95 % CI: 2.09 to 6.83, p < 0.001), respectively. These estimated parameters indicated that the EPISENS-M method could detect SARS-CoV-2 RNA in wastewater with > 50 % accuracy when newly reported cases exceeded 0.69 (95 % CI: 0.39 to 0.81)/100,000 residents in Sapporo. The COVID-19 incidence levels required for the EPISENS-M method at a certain detection probability were generally an order of magnitude lower than that of the methods used in the previous community- (catchment size: 0.12 million inhabitants) (Hewitt et al., 2022) and national-level (catchment size: 3.3–5.3 million inhabitants) (Tiwari, 2022, Wu, 2021) WBE studies (Table 1 ).Fig. 3 (A) Estimation of the detection probability of the EPISENS-M method with the logistic regression model. The circle plots denote the empirical data. The blue line denotes the logistic regression model with a 95 % confidential interval (gray shadow). From the result of Fig. 2B, a 7-day moving average centered four days after sampling day was used for the analysis. The EPISENS-M method exhibited a detection probability of > 50 % when the number of newly reported cases/ 100,000 inhabitants in Sapporo exceeded 0.69 (95 % CI: 0.39 to 0.81). (B) The fecal shedding dynamics of COVID-19 patients estimated using wastewater-based data and clinical surveillance data. The SARS-CoV-2 RNA concentrations in feces are abundant in the early stage of infection, peaking of 2.44 × 108 copies/g-feces on 0.46 days post-symptom onset. (C) The estimation of newly reported cases for 5 days (1–5 days after sampling day) with the use of two mathematical models and measured SARS-CoV-2 RNA concentration in wastewater (CRNA). The red circle plots denote the newly confirmed cases reported by clinical surveillance. The blue line denotes the estimation values based on the developed models and the geometric CRNA at two WWTPs in the same week. When SARS-CoV-2 RNA was not detected (from September 30, 2021 to December 9, 2021), the CRNA was assumed to be 7.03 copies/L, which corresponds to the square root of the LOD of the EPISENS-M method. The blue and gray shadows denote ranges within a factor of √2 and 2 estimated, respectively. (C.1) The yellow shadow represents the data area used for parameter estimation. The test result of estimation from the developed model and the data on CRNA and recent results of clinical surveillance showed that 39 % (17/44) and 68 % (30/44) of tested samples between 23 July 2021, and 16 June 2022 (n = 44) were within the blue area and the gray area, respectively. (C.2) The test result of estimation from the developed model and CRNA data showed that 41 % (18/44) and 75 % (33/44) of the tested samples between 23 July 2021 and 16 June 2022 (n = 44) were within the blue area and the gray area, respectively. SARS-CoV-2 RNA was not detected from September 19 to December 9, 2021, which could have led to the underestimation of predicted cases. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) Table 1 Comparison of detection probability for SARS-CoV-2 RNA from untreated municipal wastewater. Country Catchment Concentration PCR Regression model Infected persons per 100,0001 Reference Size (million) Detection probability 41 % 50 % 80 % Japan 0.4 Electronegative membrane Preamp –qPCR Logistic 0.59 0.69 1.03 This study Finland 3.3 Ultrafiltration qPCR Logistic 7 (Tiwari et al., 2022) New Zealand 0.12 PEG qPCR Logistic 10 (Hewitt et al., 2022) USA 5.3 PEG qPCR Kernel density 13 (Wu et al., 2021) 1 The clinical surveillance systems conducted in the corresponding regions in studies are considered to be notifiable disease surveillance. 3.4 Development of a mass balance model for predicting COVID-19 cases via WBE To estimate the newly reported COVID-19 cases from C RNA, a mathematical model was developed based on the mass balance between the total amounts of SARS-CoV-2 RNA shed from the infected individuals and that enters WWTPs in the corresponding area. The model contains a total of 4 parameters, three of which (α, β, A) are associated with the fecal shedding dynamics model, with the remaining parameter (X) representing lag time from the onset of viral shedding into WWTP to being reported as a newly infected individual by clinical surveillance. To estimate these four parameters in the model, the maximum likelihood estimation method, assuming the normal distribution of errors, or the least-squares method, was applied to the datasets consisting of newly reported COVID-19 cases and the geometric mean C RNA of the two WWTPs from 28 October 2020 to 16 July 2021 (n = 38). C RNA with or without normalization with PMMoV concentrations was used as wastewater data. The results showed that normalization of C RNA with PMMoV increased the sum of errors squared from 2.56 to 2.97, rather than improving model fitting. Based on this result, we used C RNA without PMMoV normalization for the estimation of parameters in the following analyses. The normality of the error was confirmed by a Shapiro − Wilk test (p = 0.91) and a Q-Q plot (Fig. S3). The parameters of α, β, A, and X were estimated to be 0.939, 4.22, 1.68 × 109, and 6, respectively. The estimated three parameters (α, β, A) described an average population-level viral shedding kinetics that peaked at 2.44 × 108 copies/g-feces at 0.46 days post shedding onset (DPSO) and rapidly decreased from 1.81 × 108 copies/g-feces at 1 DPSO to 9.41 × 102 copies/g-feces at 14 DPSO (Fig. 3 B). The cumulative viral shedding in feces by 5 DPSO accounted for approximately 99 % of the total cumulative viral load shed from one infection event (Fig. 3 B). The determined parameter X revealed that the infected individuals start shedding the virus into the sewer on average 6 days before being reported by clinical surveillance. 3.5 Prediction of the newly reported COVID-19 cases via WBE To demonstrate the potential of WBE to understand imminent COVID-19 cases, we estimated the total number of newly reported COVID-19 cases over the succeeding 5 days (i.e., from 1 to 5 days after the sampling day) from the developed model, viral RNA concentrations in wastewater, and recent results of clinical surveillance. The COVID-19 cases reported 6 days after sampling day were excluded for the estimation because infected individuals who would be reported 6 days after sampling day are assumed to just start shedding the virus with a concentration of 0 copies/g-feces (C(0) = 0). The geometric mean C RNA in a week and newly reported COVID-19 cases between 23 July 2021 and 16 June 2022 (n = 44) were used as the test dataset. The test results showed that 36 % (16/44) and 64 % (28/44) of tested samples were within a factor of √ 2 and 2 estimated values, respectively, demonstrating the well precision of the model prediction (Fig. 3 C(1)). We also developed a model for estimating the total number of newly reported cases without using recent data on clinical surveillance by applying the framework of the estimation model and estimated parameters above. The test results showed that 38 % (17/44) and 66 % (29/44) of tested samples were within a factor of √ 2 and 2 estimated values, respectively (Fig. 3 C(2)). As an alternative approach to supplement C RNA on non-sampling days, we estimated the newly reported cases based on linear extrapolation from the slope between the C RNA on the preceding second closest day and the preceding closest day. The result of this model (Fig. S4 in the Supplementary material) was comparable to that of the model above (Fig. 3 C(2)). 4 Discussion We present here a framework to estimate the incidence of COVID-19 in a community using C RNA and mathematical models. This population-level epidemiological information is valuable, especially in the absence of fully notifiable clinical surveillance, for public health authorities to make appropriate decisions to prevent viral spread of COVID-19. Previous studies developed models for estimating the COVID-19 incidence via WBE; however, most of them are based on simple correlation analysis and/or not subject to the validation of their estimation proficiency with long-term C RNA data including several infectious surges (Jiang, 2022, Nourbakhsh, 2022, Wu, 2022). Our prediction model is advantageous over these previously developed models as it takes into account mass balance of viral load between WWTPs and infected individuals according to the viral shedding mechanisms, which was then tested for the prediction performance with a year-long dataset of C RNA. To track C RNA for multiple years including low-prevalence periods, we developed the EPISENS-M method by modifying the EPISENS-S method (Ando et al., 2022). The EPISENS-S method has been previously proven to be more sensitive than the conventional PEG-qPCR method in detecting SARS-CoV-2 RNA in wastewater (Ando et al., 2022), but its performance can be impaired by the number of suspended solids in wastewater that are pelleted with low-speed centrifugation in the initial step of the process. To overcome this drawback, we employed electronegative membrane (pore size of 0.8 μm) filtration instead of the low-speed centrifugation used in the EPISENS-S method, because previous studies have suggested that electronegative membranes efficiently capture viruses in water with a small number of solids (e.g., treated wastewater, environmental water) (Ahmed, 2020a, Haramoto et al., 2009, Haramoto et al., 2020). It has also been reported that most SARS-CoV-2 particles in wastewater are associated with solids (Kim, 2022, Kitamura et al., 2021, Peccia, 2020) while this is true for liquids and PMMoV (Kitamura et al., 2021). In fact, the EPISENS-M method exhibited a comparable recovery yield of SARS-CoV-2 RNA but more efficiently recovered PMMoV RNA in influent wastewater as compared to the EPISENS-S method (Fig. 1 B). This result supports the robustness and high sensitivity of the EPISENS-M method for detecting SARS-CoV-2 RNA together with PMMoV RNA in influent wastewater, even with a small number of solids. We demonstrated the sensitivity of the EPISENS-M method using a logistic regression model that enables the estimation of the required number of newly reported COVID-19 cases for a method to detect SARS-CoV-2 RNA from wastewater samples. The sensitivity of detection methods is important information for understanding COVID-19 prevalence, especially in low-prevalent periods (Ahmed et al., 2022). Our result suggested that the EPISENS-M method is more sensitive than the conventional methods used in previous studies, i.e., PEG precipitation or ultrafiltration followed by ordinary RT-qPCR (Fig. 3 A, Table 1) (Haramoto et al., 2009, Tiwari, 2022, Wu, 2021). Importantly, the results also indicate that continuous non-detection of SARS-CoV-2 RNA from influent wastewater corresponds to less than one reported COVID-19 case/100,000 inhabitants in a catchment under fully notifiable clinical surveillance. Based on the longitudinal data on C RNA, we estimated four parameters (α, β, A, X) in the mass balance model that describe an average population-level fecal shedding dynamics of infected individuals (Fig. 3 B). SARS-CoV-2 RNA load in feces in the early stage of infection agreed with previous studies; however, its rate of decrease in the latter stage of infection was inconsistent with previously reported data, (Miura et al., 2021, Wu, 2022). It should be noted that population-level fecal shedding dynamics estimated with our model can be affected by inherent community characteristics (e.g., ethnicity, age, clinical surveillance system) (Prasek et al., 2022) and analytical approach (e.g., sample types, detection methods, fecal shedding models). Furthermore, the determined parameter showed that infected individuals start shedding the detectable amount of virus into the sewer for an average of 6 days before being reported by clinical surveillance, which is probably due to both the incubation time (estimated to be 4–7 days (Ejima, 2021, Zhao, 2021, Cheng, et al., 2021)) and the reporting delay associated with the time required for clinical testing and reporting. This notion is also supported by the fact that viruses shed from infected individuals before developing symptoms enter the WWTP in the corresponding area via sewer pipes, which can be immediately detected from wastewater samples. Our model succeeded in the early estimation (by 5 days) of newly reported COVID-19 cases in several infection surges from C RNA and recent results of clinical surveillance with reasonable accuracy, which demonstrates the validity of the mass-balance model framework and estimated parameters (Fig. 3 C (1)). By applying the model framework and estimated parameters, we also successfully developed the model using C RNA and estimated newly reported cases from C RNA, instead of recent clinical data (Fig. 3 C (2)). To the best of our knowledge, this is the first report to provide a validated framework to estimate the number of newly reported COVID-19 cases in a catchment solely from C RNA data in several infection surges. WBE complements clinical surveillance in terms of providing an overview of the COVID-19 pandemic status, which could be useful for public health authorities for making decisions regarding the testing strategy and movement restriction, especially when new variants are emerging in a community (Karthikeyan et al., 2022). However, it is noteworthy that the model presented in this study may underestimate the actual number of infected individuals because it was calibrated and validated with the data on the confirmed COVID-19 cases that could be largely underestimated due to limited clinical testing and the presence of undiagnosed/unreported cases. If viral shedding dynamics of infected individuals vary in response to variant prevalence and vaccination rate that might affect the asymptomatic ratio, the model calibrated with data on a certain period would show poor performance in estimating the clinically confirmed cases in the subsequent infectious surge. Interestingly, the relationship between C RNA and clinically confirmed cases seemed to be maintained during the study period, even when Sapporo faced multiple SARS-CoV-2 variants and the prevalence of vaccination intake. One of the reasons of this consistency could be the fact that Sapporo City secured sufficient clinical testing capacity by introducing the notifiable surveillance system including self-diagnosis with antigen kits, even in several infectious surges presumably caused by α, β, δ, ο variants. Conversely, the consistency suggested that variants had little impact on the viral shedding of the infected individuals, which is supported by a previous study reporting that viral loads in patients’ feces are consistent between SARS-CoV-2 variants at the logarithmic level (Prasek et al., 2023). However, further research is required for a better understanding of the impact of vaccination intake as well as prevalent variants and testing capacity on the relationship between C RNA and the newly reported cases. Importantly, our mass balance model can consider the impact of variants by adjusting the dynamics of viral shedding (C(t) copies/person/day) that may be specific to each variant. There are challenges associated with thesocial implementation of the framework proposed in the present study. First, the EPISENS-M method requires special and expensive equipment (i.e., a Precellys 24 tissue homogenizer, which costs approximately $12,000) for the bead beating step required for efficient RNA extraction from membranes (Fig. 1 A, Table S7). Further research is needed to investigate efficient RNA extraction from membranes at low initial investment. Second, we used C RNA data from two WWTPs as representative data on C RNA for the entire Sapparo City, because these sewer catchments do not correspond to the administrative wards (i.e., clinical data aggregation units) of the city. Ideally, the analysis with logistic regression model and the mathematic estimation models should be performed based on the results of the relationship between C RNA and newly reported COVID-19 cases in each sewer catchment. Next, this study used PMMoV as a normalizer of C RNA as suggested in the previous studies (Graham, 2021, Kim, 2022); however, normalization did not always improve correlation efficiency and model fitting. Previous studies have also reported that PMMoV normalization did not improve correlation efficiency at population level (Ai, 2021, Duvallet, 2021, Zheng, 2022). These results might be due to the difference between SARS-CoV-2 and PMMoV viral shedding, fate, and transport in sewer as well as viral RNA recovery and detection efficiencies. Finally, we successfully tracked the prevalence of COVID-19 via WBE by using grab sampling, which might be less representative than composite sampling (Ahmed et al., 2022). This is probably because we collected samples at a fixed time of the day (i.e., around 10AM) and SARS-CoV-2 RNA concentrations could be averaged to some extent during the transportation process in sewer and the retention process in the grit chamber of WWTPs. Grab sampling can be an inexpensive alternative to composite sampling in a relatively large sewershed under resource-limiting circumstances owing to its simplicity without requiring expensive equipment (i.e., autosampler). Additional research should examine the potential of grab sampling to gain wastewater data reflecting the COVID-19 prevalence in a community. In conclusion, we successfully developed a highly sensitive method for SARS-CoV-2 RNA detection in wastewater (EPISENS-M method) and demonstrated a high correlation between C RNA and the newly reported cases in Sapporo City, Japan based on longitudinal surveillance over two years. We also developed a mathematical model integrating viral shedding dynamics to estimate the newly reported COVID-19 cases over the succeeding 5 days solely from C RNA data. Collectively, our results highlighted the potential of WBE to predict the number of COVID-19 cases in a community when fully notifiable clinical surveillance is not practiced. The framework proposed in the present study is extremely useful, especially for regions with limited access to medical systems or clinical surveillance systems transitioning from notifiable clinical surveillance to sentinel surveillance. CRediT authorship contribution statement Hiroki Ando: Formal analysis, Investigation, Methodology, Validation, Writing – original draft. Michio Murakami: Conceptualization, Methodology, Writing – review & editing. Warish Ahmed: Methodology, Writing – review & editing. Ryo Iwamoto: Methodology, Writing – review & editing. Satoshi Okabe: Supervision, Writing – review & editing. Masaaki Kitajima: Supervision, Conceptualization, Investigation, Methodology, Funding acquisition, Writing – review & editing. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Appendix A Supplementary data The following are the Supplementary data to this article:Supplementary figure 1 Supplementary figure 2 Supplementary figure 3 Supplementary figure 4 Supplementary data 5 Supplementary data 6 Supplementary data 7 Data availability The data that has been used is confidential. Acknowledgements This study was partly funded by the JST-Mirai Program Grant Number JPMJMI22D1, Shionogi & Co., Ltd., and AdvanSentinel Inc. Appendix A Supplementary data to this article can be found online at https://doi.org/10.1016/j.envint.2023.107743. ==== Refs References Ahmed W. Comparison of virus concentration methods for the RT-qPCR-based recovery of murine hepatitis virus, a surrogate for SARS-CoV-2 from untreated wastewater Sci. Total Environ. 739 2020 Ahmed W. First confirmed detection of SARS-CoV-2 in untreated wastewater in Australia: A proof of concept for the wastewater surveillance of COVID-19 in the community Sci. Total Environ. 728 2020 Ahmed W. Evaluation of process limit of detection and quantification variation of SARS-CoV-2 RT-qPCR and RT-dPCR assays for wastewater surveillance Water Res. 213 2022 Ahmed, W. et al. Minimizing errors in RT-PCR detection and quantification of SARS-CoV-2 RNA for wastewater surveillance. Science of the Total Environment vol. 805 Preprint at https://doi.org/10.1016/j.scitotenv.2021.149877 (2022). Ai Y. Wastewater SARS-CoV-2 monitoring as a community-level COVID-19 trend tracker and variants in Ohio, United States Sci. Total Environ. 801 2021 Alene, M. et al. Magnitude of asymptomatic COVID-19 cases throughout the course of infection: A systematic review and meta-analysis. PLoS ONE vol. 16 Preprint at https://doi.org/10.1371/journal.pone.0249090 (2021). Ando H. Iwamoto R. Kobayashi H. Okabe S. Kitajima M. The Efficient and Practical virus Identification System with ENhanced Sensitivity for Solids (EPISENS-S): A rapid and cost-effective SARS-CoV-2 RNA detection method for routine wastewater surveillance Sci. Total Environ. 157101 2022 10.1016/j.scitotenv.2022.157101 Barua V.B. Tracking the temporal variation of COVID-19 surges through wastewater-based epidemiology during the peak of the pandemic: A six-month long study in Charlotte, North Carolina Sci. Total Environ. 814 2022 Cheng, C. et al. The incubation period of COVID-19: a global meta-analysis of 53 studies and a Chinese observation study of 11 545 patients. Infectious Diseases of Poverty vol. 10 Preprint at https://doi.org/10.1186/s40249-021-00901-9 (2021). Deaver J.A. COVID-19 wastewater epidemiology: a model to estimate infected populations Articles Lancet Planet Health www.thelancet.com/ 2021 Duvallet C. Nationwide Trends in COVID-19 Cases and SARS-CoV-2 RNA Wastewater Concentrations in the United States ACS Environmental Science and Technology Water 2021 10.1021/acsestwater.1c00434 Ejima K. Estimation of the incubation period of COVID-19 using viral load data Epidemics 35 2021 Gandhi, M., Yokoe, D. S. & Havlir, D. v. Asymptomatic Transmission, the Achilles’ Heel of Current Strategies to Control Covid-19. (2020) doi:10.1056/NEJMe2009758. Graham K.E. SARS-CoV-2 RNA in Wastewater Settled Solids Is Associated with COVID-19 Cases in a Large Urban Sewershed Environ. Sci. Tech. 55 2021 488 498 Gudbjartsson D.F. Spread of SARS-CoV-2 in the Icelandic Population N. Engl. J. Med. 382 2020 2302 2315 32289214 Haramoto E. Kitajima M. Katayama H. Ito T. Ohgaki S. Development of virus concentration methods for detection of koi herpesvirus in water J. Fish Dis. 32 2009 297 300 19226420 Haramoto E. Malla B. Thakali O. Kitajima M. First environmental surveillance for the presence of SARS-CoV-2 RNA in wastewater and river water in Japan Sci. Total Environ. 737 2020 Hewitt J. Sensitivity of wastewater-based epidemiology for detection of SARS-CoV-2 RNA in a low prevalence setting Water Res. 211 2022 118032 Jiang G. Artificial neural network-based estimation of COVID-19 case numbers and effective reproduction rate using wastewater-based epidemiology Water Res. 218 2022 Karthikeyan S. Wastewater sequencing reveals early cryptic SARS-CoV-2 variant transmission Nature 609 2022 101 108 35798029 Kim S. SARS-CoV-2 RNA is enriched by orders of magnitude in primary settled solids relative to liquid wastewater at publicly owned treatment works Environ Sci (Camb) 2022 10.1039/d1ew00826a Kitajima, M., Sassi, H. P. & Torrey, J. R. Pepper mild mottle virus as a water quality indicator. npj Clean Water vol. 1 Preprint at https://doi.org/10.1038/s41545-018-0019-5 (2018). Kitajima, M. et al. SARS-CoV-2 in wastewater: State of the knowledge and research needs. Science of the Total Environment vol. 739 Preprint at https://doi.org/10.1016/j.scitotenv.2020.139076 (2020). Kitamura K. Sadamasu K. Muramatsu M. Yoshida H. Efficient detection of SARS-CoV-2 RNA in the solid fraction of wastewater Sci. Total Environ. 763 2021 Lavania M. Prolonged Shedding of SARS-CoV-2 in Feces of COVID-19 Positive Patients: Trends in Genomic Variation in First and Second Wave Front Med (Lausanne) 9 2022 Ma Q. Global Percentage of Asymptomatic SARS-CoV-2 Infections among the Tested Population and Individuals with Confirmed COVID-19 Diagnosis: A Systematic Review and Meta-analysis JAMA Netw. Open Preprint at 2021 10.1001/jamanetworkopen.2021.37257 Mauro M. Persistence Viral Shedding of SARS-CoV-2 in Feces and Potential Transmission Journal of Infectious Diseases and Epidemiology 8 2022 Miura F. Kitajima M. Omori R. Duration of SARS-CoV-2 viral shedding in faeces as a parameter for wastewater-based epidemiology: Re-analysis of patient data using a shedding dynamics model Sci. Total Environ. 769 2021 Nourbakhsh S. A wastewater-based epidemic model for SARS-CoV-2 with application to three Canadian cities Epidemics 39 2022 Oran D.P. Topol E.J. Prevalence of asymptomatic SARS-CoV-2 infection A narrative review. Ann Intern Med 173 2020 362 368 32491919 Parasa, S. et al. Prevalence of Gastrointestinal Symptoms and Fecal Viral Shedding in Patients with Coronavirus Disease 2019: A Systematic Review and Meta-analysis. JAMA Network Open vol. 3 Preprint at https://doi.org/10.1001/jamanetworkopen.2020.11335 (2020). Peccia J. Measurement of SARS-CoV-2 RNA in wastewater tracks community infection dynamics Nat. Biotechnol. 38 2020 1164 1167 32948856 Prasek S.M. Population level SARS-CoV-2 fecal shedding rates determined via wastewater-based epidemiology Sci. Total Environ. 838 2022 156535 Prasek S.M. Variant-specific SARS-CoV-2 shedding rates in wastewater Sci. Total Environ. 857 2023 Rose C. Parker A. Jefferson B. Cartmell E. The characterization of feces and urine: A review of the literature to inform advanced treatment technology Crit. Rev. Environ. Sci. Technol. 45 2015 1827 1879 26246784 Park, S. kyung et al. Detection of SARS-CoV-2 in Fecal samples from patients with asymptomatic and mild COVID-19 in Korea. Clin. Gastroenterol. Hepatol. 19, 1387-1394.e2 (2021). Saththasivam J. COVID-19 (SARS-CoV-2) outbreak monitoring using wastewater-based epidemiology in Qatar Sci. Total Environ. 774 2021 Teunis P.F.M. Shedding of norovirus in symptomatic and asymptomatic infections Epidemiol. Infect. 143 2015 1710 1717 25336060 Tiwari A. Detection and quantification of SARS-CoV-2 RNA in wastewater influent in relation to reported COVID-19 incidence in Finland Water Res. 215 2022 118220 Twigg C. Wenk J. Review and Meta-Analysis: SARS-CoV-2 and Enveloped Virus Detection in Feces and Wastewater ChemBioEng Rev. 9 2022 129 145 Wu F. Wastewater surveillance of SARS-CoV-2 across 40 U.S States From February to June 2020. Water Res202 2021 Wu F. SARS-CoV-2 RNA concentrations in wastewater foreshadow dynamics and clinical presentation of new COVID-19 cases Sci. Total Environ. 805 2022 Wu, Y. et al. Prolonged presence of SARS-CoV-2 viral RNA in faecal samples. The Lancet Gastroenterology and Hepatology vol. 5 434–435 Preprint at https://doi.org/10.1016/S2468-1253(20)30083-2 (2020). Zhang Y. Prevalence and Persistent Shedding of Fecal SARS-CoV-2 RNA in Patients with COVID-19 Infection: A Systematic Review and Meta-analysis. Clinical and Translational E00343 Preprint at Gastroenterology 12 2021 10.14309/ctg.0000000000000343 Zhao S. Estimating the generation interval and inferring the latent period of COVID-19 from the contact tracing data Epidemics 36 2021 Zheng X. Quantification of SARS-CoV-2 RNA in wastewater treatment plants mirrors the pandemic trend in Hong Kong Sci. Total Environ. 844 2022 157121 Zulli A. Predicting daily COVID-19 case rates from SARS-CoV-2 RNA concentrations across a diversity of wastewater catchments FEMS Microbes 2 2022 Further reading Bi Q. Epidemiology and transmission of COVID-19 in 391 cases and 1286 of their close contacts in Shenzhen, China: a retrospective cohort study Lancet Infect. Dis. 20 2020 911 919 32353347 Sah, P. et al. Asymptomatic SARS-CoV-2 infection: A systematic review and meta-analysis. doi:10.1073/pnas.2109229118/-/DCSupplemental.
PMC009xxxxxx/PMC9833851.txt	==== Front Chest Chest Chest 0012-3692 1931-3543 American College of Chest Physicians. Published by Elsevier Inc. S0012-3692(23)00042-9 10.1016/j.chest.2023.01.008 Thoracic Oncology: Original Research The Impact of COVID-19 on Lung Cancer Incidence in England Analysis of the National Lung Cancer Audit 2019 and 2020 Rapid Cancer Registration Datasets Gysling Savannah BMBS a∗ Morgan Helen BMBS a Ifesemen Onosi Sylvia MBBS, MPH a West Douglas MBChB b Conibear John MD(Res) c Navani Neal PhD de O’Dowd Emma Louise PhD f Baldwin David R. MD f Humes David PhD g Hubbard Richard PhD af a Lifespan and Population Health, University of Nottingham, Nottingham, England b Department of Thoracic Surgery, University Hospitals Bristol and Weston NHS Trust, Bristol, England c Department of Clinical Oncology, Barts Health NHS Trust, London, England d Lungs for Living Research Centre, UCL Respiratory, University College London, London, England e Department of Thoracic Medicine, University College London Hospitals NHS Trust, London, England f Department of Respiratory Medicine, Nottingham University Hospitals NHS Trust, City Hospital, Nottingham, England g Gastrointestinal Surgery, Gastrointestinal and Liver Theme, National Institute for Health Research Nottingham Biomedical Research Centre, Nottingham University Hospitals NHS Trust and the University of Nottingham School of Medicine, Queen’s Medical Centre, Nottingham, England ∗ CORRESPONDENCE TO: Savannah Gysling, BMBS 12 1 2023 6 2023 12 1 2023 163 6 15991607 © 2023 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved. 2023 American College of Chest Physicians Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Background The COVID-19 pandemic has caused significant disruption to health-care services and delivery worldwide. The impact of the pandemic and associated national lockdowns on lung cancer incidence in England have yet to be assessed. Research Question What was the impact of the first year of the COVID-19 pandemic on the incidence and presentation of lung cancer in England? Study Design and Methods In this retrospective observational study, incidence rates for lung cancer were calculated from The National Lung Cancer Audit Rapid Cancer Registration Datasets for 2019 and 2020, using midyear population estimates from the Office of National Statistics as the denominators. Rates were compared using Poisson regression according to time points related to national lockdowns in 2020. Results Sixty-four thousand four hundred fifty-seven patients received a diagnosis of lung cancer across 2019 (n = 33,088) and 2020 (n = 31,369). During the first national lockdown, a 26% reduction in lung cancer incidence was observed compared with the equivalent calendar period of 2019 (adjusted incidence rate ratio [IRR], 0.74; 95% CI, 0.71-0.78). This included a 23% reduction in non-small cell lung cancer (adjusted IRR, 0.77; 95% CI, 0.74-0.81) and a 45% reduction in small cell lung cancer (adjusted IRR, 0.55; 95% CI, 0.46-0.65) incidence. Thereafter, incidence rates almost recovered to baseline, without overcompensation (adjusted IRR, 0.96; 95% CI, 0.94-0.98). Interpretation The incidence rates of lung cancer in England fell significantly by 26% during the first national lockdown in 2020 and did not compensate later in the year. Key Words COVID-19 incidence lung cancer NSCLC SCLC Abbreviations CCI Charlson comorbidity index IRR incidence rate ratio MD mean difference NSCLC non-small cell lung cancer RCRD Rapid Cancer Registration Dataset SCLC small cell lung cancer ==== Body pmc Take-home Points Study Question: What impact did the first year of the COVID-19 pandemic have on the incidence and presentation of lung cancer in England? Results: During the first national lockdown, a 26% (adjusted incidence rate ratio [IRR], 0.74; 95% CI, 0.71-0.78) reduction in lung cancer incidence was observed compared with the equivalent period in 2019, encompassing a 23% reduction (adjusted IRR, 0.77; 95% CI, 0.74-0.81) in non-small cell lung cancer and a 45% reduction (adjusted IRR, 0.55; 95% CI, 0.46-0.65) in small cell lung cancer incidence. Interpretation: The incidence rates of lung cancer in England fell significantly by 26% during the first national lockdown in 2020 and did not compensate later in the year. The COVID-19 pandemic has caused significant disruption to health-care services globally, with the full impact of this yet to be realized. More specifically, the effect on patients with lung cancer—the most common cause of cancer death in the United Kingdom1—has yet to be described fully. A report published by the United Kingdom Lung Cancer Coalition quotes an estimated 4.8% to 5.3% increase in 5-year mortality for patients with lung cancer as a consequence of the pandemic.2 A key determinant of lung cancer outcomes is timely diagnosis, allowing the opportunity for rapid assessment and potential initiation of treatment for this aggressively progressive disease.3 Similarly, a delay in the diagnosis of lung cancer can result in upstaging, fewer potential treatment options, and presumed worse survival outcome greater than that lost by the lead time.4 , 5 Currently, no national population-based lung cancer screening program exists to support early diagnosis in the United Kingdom, and lung cancer diagnosis commonly relies on the self-presentation of the patient or an incidental finding.6 The COVID-19 pandemic represented a unique barrier regarding patient access to lung cancer services and early diagnosis. Throughout several national lockdowns in England, the population was asked to remain at home and to self-isolate when new respiratory symptoms suggestive of viral infection emerged.7 , 8 Simultaneously, health-care resources were adapted, redeployed, and focussed on managing the COVID-19 pandemic. These factors are presumed to have affected patient access to health care, including diagnostic services. The extent of the impact of these measures and limitations on the access to health-care and diagnostic services is unclear. We sought to evaluate the impact of the COVID-19 pandemic on the incidence of lung cancer in England by analyzing the National Lung Cancer Audit 2019 and 2020 Rapid Cancer Registration Datasets. Study Design and Methods Data and Patient Population The National Cancer Registration and Analysis Service maintains the Cancer Analysis System, consisting of the Cancer Outcomes and Services Dataset, with linked data from the Hospital Episode Statistics dataset, Office for National Statistics, National Radiotherapy Dataset, and Systemic Anti-Cancer Dataset. This information is collated to produce annual Cancer Registration Datasets. For the years 2019 and 2020, these have been released in the form of Rapid Cancer Registration Datasets (RCRDs), with reduced sources (eg, lung cancers identified by death certificate registration alone), validation, and completeness compared with the usual finalized annual registrations for the sake of timely analysis and evaluation of the impact of COVID-19 on lung cancer in England. Data pertaining to all patients with a diagnosis of lung cancer in England were retrieved for audit within the framework of the nationally registered National Lung Cancer Audit. All adult patients with a diagnosis of incident primary lung cancer (as classified by code C34 of the World Health Organization’s International Classification of Diseases, Tenth Revision) in England between January 1, 2019, and December 31, 2020, were included. Patients with a diagnosis of sarcoma or mesothelioma were excluded. Patients were followed up from point of diagnosis to death or censoring. Midyear population estimates in England for 2019 and 2020 were derived from the Office for National Statistics9 for use as baseline population count. Any incidence rates per population are referring to these estimates, which also were used to calculate crude incidence per 100,000 person-years. Deprivation status was defined according to the Index of Multiple Deprivation 2019,10 scaled from least deprived (score of 1) to most deprived (score of 5). The Charlson comorbidity index (CCI)11 was used to stratify the comorbidity burden of patients, with further categorization into subgroups zero (CCI 0), one (CCI 1), two (CC 2-3), and three (CCI 4 or more). Performance status was classified according to the World Health Organization Performance Status12 (scale of 0-4, best to worst). The eighth edition of the TNM Classification of Malignant Tumours was used in the staging of all patients’I diseases. Two ranges of TNM stages were used (IA-4B vs I-IV). The former demonstrates additional detail as to the patients’ staging, and the latter was used for comparison between time periods and includes patients for whom sublevel staging was not available. Timeline of COVID-19 Pandemic The year 2020 was divided into three periods (before lockdown, first lockdown, and after lockdown), based on instrumental political and governmental decisions.13 The prelockdown period (T1) encompasses the time between January 1, 2020, and March 25, 2020. On March 26, 2020, the first and most stringent lockdown in England began. The period between this date and May 10, 2020 (lifting of the first lockdown restrictions), is defined as the first lockdown period (T2). Any time thereafter until the end of 2020 (December 31, 2020) is classified as the postlockdown period (T3). The first national lockdown was chosen as the focus of this study because the restrictions implemented during this lockdown period were the most stringent of those imposed throughout the year and public motivation for compliance was high. Statistical Analysis A descriptive summary of the baseline patient characteristics was conducted using mean ± SD for parametric data, median (interquartile range) for nonparametric data, and proportions for categorical variables. Because of the varying length of the COVID-19 periods within years, proportions and absolute number of patients were used for summative descriptions. Missing data were presented separately within summative tables. Continuous variables were evaluated using Student t test for parametric data and the Mann-Whitney U test for nonparametric data. Categorical patient variables (deprivation, comorbidity, performance status, and TNM stage) were assessed using the χ 2 or Fisher exact test, with comparison made across periods. Logistic regression models were used to evaluate overall change in the use of each referral pathway between years (using 2019 as the reference group), adjusted for sex and age. The 2-week wait pathway refers to the urgent referral pathway through which patients with suspected cancer are referred to secondary care in the United Kingdom. Results were summarized in the form of adjusted ORs as appropriate, with 95% CIs. Midyear population estimates in England were used for baseline population count in the calculation of crude incidence rates per 100,000 person-years. Monthly incidence rates were calculated using this baseline and were adjusted for person-time. Poisson regression was used to model the incidence rates in adjusted models, with results reported as adjusted incidence rate ratios (IRRs) per person-time. Results were stratified by the COVID-19 periods, with comparison of the three defined periods (T1, T2, and T3) in 2020 with the equivalent periods in 2019. Monthly incidence rates were analyzed, with each month in 2020 compared with the same period in 2019. For between-year (2019 vs 2020) comparisons, the 2019 cohort was used as a baseline. Subgroup analysis of patients with non-small cell lung cancer (NSCLC) and with small cell lung cancer (SCLC) was performed because of the clinical impact of these differential diagnoses. A P value of < .05 was considered statistically significant. All analyses were performed using Stata Statistical Software release 17 (StataCorp LLC). Results Patient Demographics Sixty-four thousand four hundred fifty-seven patients (men, n = 33,349 [51.7%]) received a diagnosis of lung cancer across 2019 (n = 33,088) and 2020 (n = 31,369) was found. No difference was found in median age of those with a diagnosis of lung cancer between 2019 and 2020 (Table 1 ). In 2020, more data for smoking status were missing compared with 2019 (Table 1). No differences were observed in the age or sex of those with a diagnosis of either NSCLC or SCLC across the 2 years.Table 1 Characteristics for All Patients With Lung Cancer in 2019 and 2020 Variable 2019 2020 Total All lung cancer No. of patients 33,088 31,369 64,457 Age, y 73 (66-80) 73 (66-80) 73 (66-80) Male sex 17,184 (51.9) 16,165 (51.5) 33,349 (51.7) Smoking status Smoker 6,785 (20.5) 5,497 (17.5) 12,282 (19.1) Former smoker 11,551 (34.9) 8,901 (28.4) 20,452 (31.7) Nonsmoker 351 (1.1) 184 (0.6) 535 (0.8) Never smoker 1,552 (4.7) 1,338 (4.3) 2,890 (4.5) Declined 20 (0.1) 2 (0.0) 22 (0.0) Missing 12,829 (38.8) 15,447 (49.2) 28,276 (43.9) NSCLC No. of patients 29,480 28,338 57,818 Age, y 73 (66-80) 74 (66-80) 73 (66-80) Male sex 15,469 (52.5) 14,751 (52.1) 30,220 (52.3) SCLC No. of patients 2,996 2,555 5,551 Age, y 70 (76-97) 70 (76-97) 70 (76-97) Male sex 1,508 (50.3) 1,245 (48.7) 2,753 (49.6) Data are presented as No. (%) or median (interquartile range), unless otherwise indicated. NSCLC = non-small cell lung cancer; SCLC = small cell lung cancer. Pathway to Diagnosis A change in the use of referral pathways that lead to lung cancer diagnosis occurred in 2020. Adjusting for patient age and sex, emergency presentations (OR, 1.21; 95% CI, 1.18-1.26; P < .001) and other outpatient referrals (OR, 1.08; 95% CI, 1.04-1.13; P < .001) increased, whereas general practitioner referrals (OR, 0.89; 95% CI, 0.86-0.93; P < .001) and 2-week wait referrals (OR, 0.82; 95% CI, 0.79-0.85; P < .001) were reduced compared with 2019. No significant difference in inpatient elective referrals was observed (OR, 0.96; 95% CI, 0.85-1.09; P = .571) (Fig 1 ).Figure 1 Bar graph showing a comparison of the use of referral pathways for all patients with lung cancer in 2019 and 2020. Statistically significant differences: aP < .05, bP < .01, and cP < .001. GP = general practitioner; TWW = 2-wk wait. Incidence of Lung Cancer The crude incidence rate of lung cancer diagnosis fell from 58.5 to 55.4 per 100,000 person-years in England in 2020 compared with 2019 (adjusted IRR, 0.95; 95% CI, 0.94-0.97). The distribution of lung cancers diagnosed in 2019 and 2020 across age groups is displayed in Figure 2 . In the context of the pandemic and adjusting for age and sex, the incidence of lung cancer diagnosis during the prelockdown period was 4% higher (adjusted IRR, 1.04; 95% CI, 1.01-1.08) compared with the equivalent time period in 2019. During the first national lockdown in 2020, a 26% reduction in lung cancer incidence rates was observed compared with the equivalent period of the previous year (adjusted IRR, 0.74; 95% CI, 0.71-0.78). During the postlockdown period, incidence rates were only slightly lower than in the same period in 2019 (adjusted IRR, 0.96; 95% CI, 0.94-0.98) (Table 2 ). The monthly unadjusted incidence of lung cancer (per 100,000 person-years) and monthly adjusted (for age and sex) IRR for both years is displayed in Figure 3 . The largest relative reduction in lung cancer incidence occurred during May 2020, representing a 32% reduction in incidence rates compared with the same month in 2019 (adjusted IRR, 0.68; 95% CI, 0.64-0.72).Figure 2 Bar graph showing the number and IR of patients with lung cancer across age groups in 2019 and 2020. IR = incidence rate (unadjusted). Table 2 Incidence of Lung Cancer Across COVID-19 Periods Variable IR/100,000 Person-Y Adjusted IRRa 95% CI 2019 2020 All lung cancer T1 58.53 60.50 1.04 1.01-1.08 T2 59.39 43.67 0.74 0.71-0.78 T3 58.58 55.78 0.96 0.94-0.98 NSCLC T1 52.38 54.57 1.05 1.02-1.09 T2 52.56 39.94 0.77 0.74-0.81 T3 52.16 50.31 0.98 0.96-1.00 SCLC T1 5.20 4.86 0.93 0.84-1.04 T2 5.48 3.02 0.55 0.46-0.65 T3 5.33 4.68 0.87 0.82-0.93 NSCLC = non-small cell lung cancer; SCLC = small cell lung cancer; T1 = January 1-March 25 (prelockdown period in 2020); T2 = March 26-May 10 (first national lockdown period in 2020); T3 = May 11-December 31 (postlockdown period in 2020). a Adjusted for sex and age. Figure 3 Bar graph showing the monthly IRs for all lung cancer cases in 2019 and 2020. The section highlighted in light pink represents the period of the first national lockdown. IR = incidence rate (unadjusted); Adjusted IRR = incidence rate ratio (adjusted for age and sex). Non-Small Cell and Small Cell Lung Cancer Incidence The crude incidence rate of NSCLC fell from 52.37 per 100,000 person-years in 2019 to 50.11 per 100,000 person-years in 2020 (adjusted IRR, 0.97; 95% CI, 0.95-0.98). In patients with SCLC, the incidence rate fell from 5.32 per 100,000 person-years in 2019 to 4.52 per 100,000 person-years in 2020 (adjusted IRR, 0.85; 95% CI, 0.80-0.89). The incidence rates remained stable in the prelockdown period of 2020 compared with 2019 for both patients with NSCLC and those with SCLC (Table 2). During the first national lockdown, a 23% reduction in NSCLC incidence rates was observed compared with the equivalent period in 2019 (adjusted IRR, 0.77; 95% CI, 0.74-0.81). During the same period, a 45% reduction in SCLC incidence rates was observed (adjusted IRR, 0.55; 95% CI, 0.46-0.65) (Table 2). In the postlockdown period of 2020, incidence rates of NSCLC recovered (adjusted IRR, 0.98; 95% CI, 0.96-1.00) compared with the equivalent period in 2019, without compensation for the reduction observed during the first lockdown period. In the SCLC group, incidence remained substantially lower than baseline (adjusted IRR, 0.87; 95% CI, 0.82-0.93) (Table 2). The largest reduction in the monthly incidence rates occurred during April 2020 for patients with NSCLC (adjusted IRR, 0.68; 95% CI, 0.64-0.72) compared with April 2019 (e-Fig 1). For patients with SCLC, the greatest reduction occurred during April 2020 (adjusted IRR, 0.57; 95% CI, 0.46-0.70) (e-Fig 2). Patient Characteristics Patient demographic and performance characteristics across periods in 2019 and 2020 can be seen in Table 3 (all lung cancer) and in e-Table 1 (NSCLC) and e-Table 2 (SCLC). A difference in the performance status of patients with lung cancer was found during the first lockdown (P = .002) compared with the equivalent periods in 2019; however, this effect was negated on exclusion of patients with missing data, and the absolute differences between proportions across periods were small (Table 3). During the postlockdown period, a significant shift occurred in the performance status of lung cancer patients toward worsening (P < .001), which could not be accounted for by missing data alone, with fewer patients with a performance status of zero at presentation (Table 3).Table 3 Characteristics of Patient With Lung Cancer Across COVID-19 Periods in 2019 and 2020 Variable T1 T2 T3 Deprivation (IMD 2019) 2019 2020 2019 2020 2019 2020 1 14.2 (1,089) 14.1 (1,122) 15.3 (644) 13.8 (430) 14.1 (3,000) 14.8 (3,002) 2 18.6 (1,424) 19.3 (1,534) 18.7 (788) 18.7 (581) 18.4 (3,910) 18.6 (3,778) 3 19.8 (1,516) 19.9 (1,586) 18.7 (788) 20.2 (629) 20.1 (4,270) 19.7 (3,999) 4 21.4 (1,641) 21.3 (1,692) 22.0 (928) 21.3 (663) 21.7 (4,595) 21.5 (4,371) 5 26.0 (1,994) 25.5 (2,028) 25.2 (1,063) 26.0 (809) 25.6 (5,438) 25.4 (5,145) Total 100 (7,664) 100 (7,962) 100 (4,211) 100 (3,112) 100 (21,213) 100 (20,295) Comorbidity 2019 2020 2019 2020 2019 2020a 0 65.3 (5,006) 64.8 (5,161) 65.5 (2,756) 66.4 (2065) 65.2 (13,821) 65.7 (13,342) 1 13.8 (1,054) 14.7 (1,167) 13.5 (567) 14.3 (444) 13.9 (2,957) 14.6 (2,970) 2 14.8 (1,132) 14.6 (1,165) 15.3 (643) 13.2 (411) 15.0 (3,188) 13.9 (2,819) 3 6.2 (472) 5.9 (469) 5.8 (245) 6.2 (192) 6.0 (1,247) 5.7 (1,164) Total 100 (7,664) 100 (7,962) 100 (4,211) 100 (3,112) 100 (21213) 100 (20,295) Performance status 2019 2020b 2019 2020a 2019 2020c 0 19.6 (1,504) 20.4 (1,627) 20.8 (877) 18.9 (587) 20.3 (4,299) 16.7 (3,391) 1 32.0 (2,545) 30.4 (2,419) 32.2 (1,354) 30.3 (943) 31.3 (6,635) 28.2 (5,718) 2 16.5 (1,264) 16.6 (1,322) 15.8 (666) 16.2 (504) 16.7 (3,536) 16.9 (3,433) 3 16.5 (1,261) 16.6 (1,323) 16.6 (700) 17.8 (553) 16.3 (3,448) 17.8 (3,613) 4 5.7 (436) 5.0 (399) 5.3 (225) 5.1 (158) 4.8 (1,023) 5.8 (1,181) Missing 9.7 (745) 11.0 (872) 9.2 (389) 11.8 (367) 10.7 (2,272) 14.6 (2,959) Total 100 (7,664) 100 (7,962) 100 (4,211) 100 (3,112) 100 (21,213) 100 (20,295) TNM stage 2019 2020a 2019 2020 2019 2020c I 19.0 (1,458) 21.7 (1,731) 19.5 (822) 19.6 (611) 20.2 (4,285) 19.1 (3,882) II 8.2 (626) 8.2 (654) 8.1 (340) 8.1 (252) 8.1 (1,709) 6.2 (1,266) III 21.7 (1,663) 20.6 (1,642) 21.4 (903) 19.1 (593) 21.3 (4,517) 18.5 (3,763) IV 43.4 (3,324) 41.5 (3,303) 44.0 (1,853) 45.4 (1,413) 42.9 (9,106) 45.2 (9,163) Missing 7.7 (593) 7.9 (632) 7.0 (293) 7.8 (243) 7.5 (1,596) 10.9 (2,221) Total 100 (7,664) 100 (7,962) 100 (4,211) 100 (3,112) 100 (21,213) 100 (20,295) Data are presented as % (No.). IMD = Index of Multiple Deprivation; T1 = January 1-March 25 (prelockdown period in 2020); T2 = March 26-May 10 (first national lockdown period in 2020); T3 = May 11-December 31 (postlockdown period in 2020). a Statistically significant for P < .01, 2020 vs 2019. b Statistically significant for P < .05, 2020 vs 2019. c Statistically significant for P < .001, 2020 vs 2019. Stage During the first national lockdown, no change in TNM stage distribution was observed compared with that in 2019 (P = .109) (Table 3). After the first lockdown was lifted, a stage shift was observed (P < .001) compared with the equivalent period in 2019, with reduced stage I (mean difference [MD], –1.1%), stage II (MD, –1.8%), and stage III (MD, –2.8%) presentations and increased stage IV (MD, 2.2%) presentations in the context of increased missing data in 2020 (MD, 3.4%) (Table 3). Further description of the TNM stage distribution across patients with NSCLC and SCLC can be found in e-Tables 3 and 4. Discussion Our analysis of the 2019 and 2020 RCRDs shows a 26% reduction in lung cancer incidence during the first national lockdown in 2020, with a 23% decrease in NSCLC and 45% decrease in SCLC incidence rates during this period. Given the relatively stable incidence rate of lung cancer in the United Kingdom in the preceding decade,14 this represents a novel and unprecedented change. Evidence was found of stage migration and worsening performance status of patients with lung cancer after the first lockdown period. Although ambulatory services for patients with lung cancer remained largely unchanged and available throughout the pandemic, multiple factors may have impeded access to these, particularly for patients with lung cancer who tend to seek treatment at an older age with multiple comorbidities, such as fear of contracting COVID-19, lockdown regulations restricting movement, and limitations in transport availability. Decreased routine care for these comorbidities and therefore increased overall morbidity, as reflected in the decrease in performance status observed, may have contributed to the reduced lung cancer incidence. Given the lack of compensation of the incidence rates after lockdown, as well as the stage shift observed, these so-called missing cases also may be attributable in part to patients who died without receiving a diagnosis. This is supported by our findings that the fall in incidence was greater for SCLC, a more aggressive cancer, in which patients have less time to seek treatment before they die. Relevant Literature An Italian multicenter study15 assessed the incidence of lung cancer in 2020 compared with the previous year. They reported a 6.9% reduction in lung cancer diagnosis in 2020 compared with 2019, with the maximum reduction occurring during May 2020. In a two-center study from Spain, Reyes et al16 found a 38% reduction in lung cancer cases diagnosed during the defined COVID-19 period compared with baseline. Kasymjanova et al17 report a 21% reduction in lung cancer diagnosis in 2020 compared with 2019 at a single Canadian institution. These collective reports of reduced lung cancer diagnoses resulting from the pandemic are limited in part by the variation in the periods analyzed, the inability to adjust for potential confounding by sex and age, and the small sample sizes. Furthermore, the management and adaptation of health-care services during the pandemic has varied widely across regions and nations, as has the timeline of COVID-19 peaks and national lockdowns, which undoubtably have impacted lung cancer diagnosis differentially. To our knowledge, our study represents the first national description of the impact of lockdowns on the incidence of lung cancer. Importantly, the overall lung cancer diagnostic services were able to recover after the first national lockdown and throughout the subsequent second lockdown in England. The latter were less stringent in their restrictions and allowed for tiered, regional variation, dependant on COVID-19 case numbers. It is possible that these factors, as well as growing experience with the novel virus, allowed the diagnostic services to adapt and more patients to seek treatment. As the pandemic continues, it is important that these services be preserved, with both patients and health-care services continuing to prioritize the early diagnosis and screening for lung cancer. Few reports exist on the impact of the pandemic on the TNM stage of patients with lung cancer at diagnosis. Our study found a significant shift toward patients seeking treatment with stage IV lung cancer after the first national lockdown. Cantini et al15 observed a similar increase in the proportion of patients with lung cancer seeking treatment with stage IV lung cancer in 2020 compared with 2019 (2019, 67% vs 2020, 72%; P < .01). Similarly, Carroll et al18 reported a shift toward stage IV disease in patients with NSCLC during the pandemic (34.4% vs 46.3%; P = .01), whereas Reyes et al16 found more advanced NSCLC disease at presentation during the COVID-19 period. It is known that lung cancer may progress rapidly, with a median volume doubling time of approximately 104 days4 (average of 70 days in SCLC),19 depending on cell type, disease stage, and patient factors. Any delay in diagnosis therefore is assumed to have critical effects on tumor upstaging, as well as in the determination of subsequent treatment options and outcomes.2 Lockdowns may have led to reduced physical activity, particularly in the elderly, and resultant physical and mental deconditioning.20 This could explain the shift toward worse performance status at presentation observed in our analysis. Carroll et al18 did not find any significant shift in the performance status of 491 patients with lung cancer seeking treatment over a 12-month period (December 2019-November 2020), although the potential shift may have been too small to detect in this population. The performance status is vital in determining both available management options for patients with lung cancer, as well as outcome with treatment. This may present an area for targeted intervention to improve outcomes for patients with lung cancer. Study Strengths The RCRDs provide an overview of patients who receive a diagnosis of lung cancer in England, capturing changes affecting these patients at a national level. The strength of this work lies not only in the population size encompassed, but also in the range of patient and health-care factors yielded by the combined use of several linked datasets. Through the release of these newly developed RCRDs, we were able to perform a timely analysis of the evolving impact of the COVID-19 pandemic, which may inform the ongoing response to the pandemic. Study Limitations The newly developed RCRDs allow for timely analysis of the changes in lung cancer diagnosis brought on by the pandemic, albeit at the cost of reduced validation and follow-up time. For example, the large proportion of missing values for smoking status precluded further analysis of this factor beyond a yearly analysis. Furthermore, lung cancers identified by death certificate registration alone were not included in the RCRDs and may account selectively for some of the missing cases. Because these datasets are a preliminary component of the eventual gold standard registration data, our results may not match subsequent National Statistics publications. They also represent a retrospective viewpoint on a rapidly evolving situation with a limited follow-up period, potentially leading to underestimation of the true impact of the pandemic on patients with lung cancer. Full details regarding the quality of these datasets are available at www.ncin.org.uk/collecting_and_using_data/rcrd. We acknowledge that dividing the years into COVID-19 periods results in an unequal distribution of the absolute number of patients per period and relatively small group numbers in the SCLC cohort. This may be reflected in less precise crude incidence rates and wider CIs surrounding the adjusted IRRs pertaining to this group. The interpretation of the comparative patient characteristics therefore was focussed on proportions rather than absolute numbers. Interpretation The incidence of lung cancer has been affected significantly by the COVID-19 pandemic and associated societal and health-care changes, with those with SCLC most disadvantaged. The pandemic has illustrated what happens when access to prompt diagnosis is severely limited. As the pandemic continues, it is vital that awareness campaigns are enhanced and linked to prompt access to clinical triage, early diagnosis, and appropriate treatment to mitigate excess mortality from a cancer that causes almost one-fifth of cancer deaths. Funding/Support N. N. is supported by a 10.13039/501100000265 Medical Research Council Clinical Academic Research Partnership [Grant MR/T02481X/1]. Work relating to the National Lung Cancer Audit was undertaken partly at the 10.13039/501100000765 University College London Hospitals/University College London and received a proportion of funding from the Department of Health’s 10.13039/501100000272 National Institute for Health Research Biomedical Research Centre’s funding scheme. Financial/Nonfinancial Disclosures None declared. Supplementary Data e-Online Data Audio Acknowledgments Author contributions: S. G. contributed to conceptualization, methodology, formal analysis, investigation, writing the original draft, and visualization. H. M. contributed to resources, data analysis, and reviewing and editing the draft. O. I. contributed to data analysis. D. W., J. C., and N. N. contributed to reviewing and editing the draft. E. O. and D. B. contributed to conceptualization and reviewing and editing the draft. D. H. contributed to conceptualization, resources, methodology, reviewing and editing the draft, supervision, and project administration. R. H. contributed to conceptualization, resources, methodology, reviewing and editing the draft, supervision, and project administration. Role of sponsors: The sponsor had no role in the design of the study, the collection and analysis of the data, or the preparation of the manuscript. Additional information: The e-Figures and e-Tables are available online under “Supplementary Data.” ==== Refs References 1 Cancer mortality for common cancers. Cancer Research UK. Accessed December 20, 2022. https://www.cancerresearchuk.org/health-professional/cancer-statistics/mortality/common-cancers-compared#heading-Zero 2 Maringe C. Spicer J. Morris M. The impact of the COVID-19 pandemic on cancer deaths due to delays in diagnosis in England, UK: a national, population-based, modelling study Lancet Oncol 21 8 2020 1023 1034 32702310 3 Tsai C.H. Kung P.T. Kuo W.Y. Tsai W.C. Effect of time interval from diagnosis to treatment for non-small cell lung cancer on survival: a national cohort study in Taiwan BMJ Open 10 4 2020 e034351 4 Kanashiki M. Tomizawa T. Yamaguchi I. Volume doubling time of lung cancers detected in a chest radiograph mass screening program: comparison with CT screening Oncol Lett 4 3 2012 513 516 22970048 5 Pujol J.L. Quantin X. Time to diagnosis of lung cancer: technical and pyschological factors that slow down diagnostic and treatment timelines J Thorac Oncol 4 10 2009 1192 1194 20197732 6 Adult screening programme lung cancer. UK National Screening Committee. Accessed December 20, 2022. https://view-health-screening-recommendations.service.gov.uk/lung-cancer/. 7 Stay at home: guidance for households with possible or confirmed coronavirus (COVID-19) infection. United Kingdom Health Security Agency. Accessed December 20, 2022. https://www.gov.uk/government/publications/covid-19-stay-at-home-guidance/stay-at-home-guidance-for-households-with-possible-coronavirus-covid-19-infection. 8 Round T. L’Esperance V. Bayly J. COVID-19 and the multidisciplinary care of patients with lung cancer: an evidence-based review and commentary Brit J Cancer 125 5 2021 629 640 33972746 9 Population estimates for the UK, England and Wales, Scotland and Northern Ireland: mid-2020. UK Office for National Statistics. Accessed December 20, 2022. https://www.ons.gov.uk/peoplepopulationandcommunity/populationandmigration/populationestimates/bulletins/annualmidyearpopulationestimates/mid2020. 10 UK Ministry of Housing The English Indices of Deprivation 2019 Research Report 2019 UK Ministry of Housing 11 Charlson M.E. Pompei P. Ales K.L. MacKenzie C.R. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation J Chron Dis 40 5 1987 373 383 3558716 12 Oken M.M. Creech R.H. Tormey D.C. Toxicity and response criteria of the Eastern Cooperative Oncology Group Am J Clin Oncol 6 5 1982 649 655 13 Timeline of UK coronavirus lockdowns, March 2020 to March 2021. Institute for Government. Accessed December 20, 2022. https://www.instituteforgovernment.org.uk/charts/uk-government-coronavirus-lockdowns. 14 Lung cancer incidence statistics. Cancer Research UK. Accessed December 20, 2022. https://www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/lung-cancer/incidence#heading-Two. 15 Cantini L, Mentrasti G, Siena S. Impact of COVID19 outbreak on lung cancer diagnosis and continuum of care: data from an Italian multicenter study. Paper presented at: IASLC 2021 World Conference on Lung Cancer Hosted by the International Association for the Study of Lung Cancer; August 9, 2021. 16 Reyes R. López-Castro R. Auclin E. MA03.08 Impact of COVID-19 pandemic in the diagnosis and prognosis of lung cancer J Thorac Oncol 16 3 2021 S141-S141 17 Kasymjanova G. Anwar A. Cohen V. The impact of COVID-19 on the diagnosis and treatment of lung cancer at a Canadian academic center: a retrospective chart review Curr Oncol 28 6 2021 4247 4255 34898542 18 Carroll H. Doyle M. Eaton D. FP06.02 the impact of the COVID-19 pandemic on new diagnoses of lung cancer: a 3-year review of an Irish cancer centre J Thorac Oncol 16 10 2021 S954-S954 19 Sharial M.S.N.M. Teo M. Doherty M. McDermott R.S. Walshe J.M. Modern imaging technique assessment of small cell lung cancer doubling time J Clin Oncol 30 15 suppl 2012 e17561-e17561 20 Public Health England Wider Impacts of COVID-19 on Physical Activity, Deconditioning and Falls in Older Adults 2021 Public Health England
PMC009xxxxxx/PMC9839959.txt	==== Front Food Environ Virol Food Environ Virol Food and Environmental Virology 1867-0334 1867-0342 Springer US New York 36640204 9548 10.1007/s12560-022-09548-7 Original Paper Rapid Detection of Hepatitis A Virus in Foods Using a Bioluminescent Assay in Real-Time (BART) and Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP) Technology http://orcid.org/0000-0003-3078-7636 Wu Ruiqin [email protected] 12 Meng Baozhong 3 Corredig Milena 1 Griffiths Mansel W. 12 1 grid.34429.38 0000 0004 1936 8198 Department of Food Science, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1 Canada 2 Canadian Research Institute for Food Safety, 43 McGilvray Street, Guelph, ON N1G 2W1 Canada 3 grid.34429.38 0000 0004 1936 8198 Department of Molecular and Cellular Biology, University of Guelph, 50 Stone Road East, Guelph, ON N1G 2W1 Canada 14 1 2023 2023 15 2 144157 31 5 2022 30 12 2022 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Foodborne hepatitis A infections have been considered as a major threat for public health worldwide. Increased incidences of hepatitis A virus (HAV) infection has been associated with growing global trade of food products. Rapid and sensitive detection of HAV in foods is very essential for investigating the outbreaks. Real-time RT-PCR has been most widely used for the detection of HAV by far. However, the technology relies on fluorescence determination of the amplicon and requires sophisticated, high-cost instruments and trained personnel, limiting its use in low resource settings. In this study, a robust, affordable, and simple assay, reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay in combination with a bioluminescence-based determination of amplification in real-time (BART), was developed for the detection of HAV in different food matrices, including green onion, strawberry, mussel, and milk. The efficiencies of a one-step RT-LAMP-BART and a two-step RT-LAMP-BART were investigated for the detection of HAV in different food matrices and was compared with that of real-time RT-PCR. The sensitivity of the RT-LAMP-BART assay was significantly affected by Mg2+ concentration (P < 0.05), in addition to primer quality. The optimal Mg2+ concentration was 2 mM for one-step RT-LAMP-BART and 4 mM for two-step RT-LAMP-BART. Compared with cartridge-purified primers, HPLC-purified primers could greatly improve the sensitivity of the RT-LAMP-BART assay (P < 0.05). For detecting HAV in different food matrices, the performance of two-step RT-LAMP-BART was comparable with that of real-time RT-PCR and was better than that of one-step RT-LAMP-BART. The detection limit of the two-step RT-LAMP-BART for HAV in green onion, strawberry, mussel, and milk was 8.3 × 100 PFU/15 g, 8.3 × 101 PFU/50 g, 8.3 × 100 PFU/5 g, and 8.3 × 100 PFU/40 mL, respectively. The developed RT-LAMP-BART was an effective, simple, sensitive, and robust method for foodborne HAV detection. Keywords Hepatitis A virus Detection RT-LAMP-BART Food http://dx.doi.org/10.13039/501100000094 Ontario Ministry of Agriculture, Food and Rural Affairs FS080739 Griffiths Mansel W. issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction Foodborne illnesses are usually caused by consumption of food or water contaminated with harmful bacteria, viruses, parasites or chemical substances (WHO, 2020). Human pathogenic viruses are the most frequent causative agents and hepatitis A virus (HAV) is one of the greatest concerns which has caused numerous foodborne disease outbreaks in the world (Di Cola et al., 2021). HAV causes hepatitis A disease that is an inflammation of liver. The symptoms can range from mild to severe, including fever, malaise, loss of appetite, diarrhea, nausea, abdominal discomfort, dark-colored urine and jaundice (EFSA, 2014; Fleet et al., 2000; Sánchez et al., 2002). It was estimated that 7134 people died from hepatitis A worldwide in 2016 alone (WHO, 2021). Foodborne outbreaks of hepatitis A have been on the rise in recent years because of increasing numbers of international travelers, mass global migration, and the fast growth of global food trade (Bhaskar, 2017; Bosch et al., 2018; Cheftel, 2011; Hu et al., 2020; Kannan et al., 2020). The worldwide increase in the occurrence of foodborne HAV outbreaks has necessitated the development of novel approaches for rapid identification of foods contaminated with HAV, which is essential for implementing intervention strategies to prevent and reduce illnesses caused by the virus. Real-time RT-PCR was used in the ISO 15216–2:2019 as a standard method for the detection of HAV in different food matrices, such as food surface (bell pepper pieces), raspberries, lettuce, green onion, oysters (Crassostrea gigas), mussels (Mytilus edulis), and bottled water (ISO, 2019). Although the method is reliable and accurate, it requires trained personnel and sophisticated equipment which can regulate temperature cycling and detect fluorescent signals emitted from the excited fluorophore (Li et al., 2017). These drawbacks restrict its widespread application in resource-limited settings. It is hard to detect HAV in foods because the viral contamination level may be low and significant inhibitors in food can prevent real-time PCR assay from working properly (Sánchez et al., 2007). Therefore, there is a growing demand for devising a novel strategy for rapid, robust, sensitive, and cost-effective detection of HAV in food items using simple equipment. The recent development of isothermal amplification techniques for nucleic acid provides a variety of alternatives of PCR-based methods (Zhou et al., 2014). Among the methods, loop-mediated isothermal amplification (LAMP) has shown to be the most promising due to its rapidity, simplicity, high efficiency and specificity (Niessen et al., 2013). LAMP assay was first described for the detection of nucleic acids of hepatitis B virus (HBV) in 2000 (Notomi et al., 2000). This method employs Bst DNA polymerase, an enzyme derived from Geobacilus stearothermophilus (formally Bacillus stearothermophilus), with strand displacement activity (Nagamine et al., 2002; Notomi et al., 2000). The amplification is conducted at a constant temperature between 60 and 65 °C and does not need an expensive thermal cycler. Aside from its isothermal character, LAMP has several important features: (1) LAMP shows exquisite specificity because of the involvement of four primers: two inner primers (FIP and BIP) and two outer primers (F3 and B3), which can specifically recognize six regions of the target. Additional primers, Loop primers (Nagamine et al., 2002), and/or STEM primers (Gandelman et al., 2011), can be used to accelerate the LAMP reaction; (2) the product of LAMP consists of a mixture of stem-loop DNAs with various sizes, giving rise to distinct ladder-like banding patterns on an agarose gel (Notomi et al., 2000); (3) the LAMP reaction can be easily detected by visual endpoint observation of a white precipitate of magnesium pyrophosphate (Mori & Notomi, 2009), or of the color change of calcein (Tomita et al., 2008), SYBR Green I (Njiru et al., 2012; Tao et al., 2011), hydroxynaphthol blue (Goto et al., 2009; Vu et al., 2016), or phenol red (Amaral et al., 2021) involved in the reaction; (4) LAMP product can be monitored by a real-time measurement of the turbidity of magnesium pyrophosphate, a byproduct of DNA amplification (Mori et al., 2004); (5) the LAMP reaction is more tolerant to substances that typically inhibit PCR (Francois et al., 2011; Kaneko et al., 2007; Ou et al., 2012); and (6) portable devices, such as coin-size microfluidic chips or smartphone-based mobile detection platform, can be designed to fulfill the need for on-site detection using the LAMP technique in remote areas where resources are limited (Ahmad et al., 2011; Hsieh et al., 2012; Liu et al., 2011; Lucchi et al., 2010; Song et al., 2018; Wang et al., 2020; Wu et al., 2011; Yi et al., 2014). Due to these features, LAMP assay has stimulated extensive research interest and has been applied for food analysis, such as for the detection of allergens (Mao et al., 2020; Sheu et al., 2018; Yuan et al., 2018), genetically modified crops (Li et al., 2013; Zhou et al., 2014), and for meat species identification (Aartse et al., 2017; Abdulmawjood et al., 2014; Girish et al., 2020; Kumari et al., 2020; Wang et al., 2019; Xiong et al., 2020; Zahradnik et al., 2015). In addition, LAMP assay has been widely used for the detection of viral, bacterial, fungal, and parasitic pathogens (Cao et al., 2019; Ferrara et al., 2015; Frisch & Niessen, 2019; Li et al., 2017; Mei et al., 2019; Niessen et al., 2013). In LAMP assay, the large amounts of DNA produced during amplification lead to liberation of enormous concentration of a side product, inorganic pyrophosphate ions (PPi). Each time a nucleotide base is added during the polymerization reaction, a molecule of PPi is released. The amount of PPi produced is proportional to the amount of polynucleotide synthesized, and hence the concentration of the target template in the test material. The synthesized PPi can be converted to ATP by ATP sulfurylase using adenosine 5’-phosphosulfate (APS) as the substrate. The ATP generated is simultaneously used by firefly luciferase to oxidize its substrate luciferin to emit light. Based on this mechanism as shown in Fig. 1, the dynamic changes of PPi, and hence, the DNA amplification can be monitored by testing the light output in a real-time mode. During DNA amplification, with the increase of PPi liberated, the light signal increases rapidly firstly, and later the PPi molecules accumulated in the reaction inhibit luciferase. Together with the depletion of the substrate adenosine 5′phosphosulphate (APS) in the reaction, the light output decreases. The time at which the peak is detected (time-to-peak) is inversely proportional to the concentration of the initial template (Gandelman et al., 2010; Hardinge et al., 2020; Kiddle et al., 2012). The combination of LAMP reaction and bioluminescence assay in real-time is described as LAMP-BART technique for the detection of DNA template; when RNA is the detection target, the method is named RT-LAMP-BART (Gandelman et al., 2010). This luminescence-based assay is more cost-effective than a fluorescence-based assay such as real-time PCR, and it is more tolerant to substances that typically inhibit PCR (Kiddle et al., 2012). The LAMP-BART assay has been used in the detection of genetically modified maize (Hardinge et al., 2018; Kiddle et al., 2012), human parvovirus B19 (Mirasoli et al., 2018), and SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) during the COVID-19 pandemic (Fei et al., 2021).Fig. 1 Chemical mechanism of LAMP-BART assay (Gandelman et al., 2010) (Color figure online) In this study, we for the first time developed a RT-LAMP-BART assay for rapid detection of HAV in different food matrices including green onion, strawberry, mussel, and milk, which have been associated with foodborne HAV outbreaks (Wu et al., 2019, 2022). Materials and Methods Virus Propagation and Cell Line The cytopathogenic HM175/24A strain of HAV was propagated in fetal rhesus monkey kidney cells (FRhk-4), and the virus was enumerated by a plaque assay as described in our previous report (Wu et al., 2019). The viral titer was expressed as plaque forming unit (PFU) per mL. The viral stock was stored at − 80 °C until further analysis. Food Sample Contamination HAV was inoculated onto solid foods including green onion (15 g), strawberry (50 g), mussel (5 g), and into liquid food (40 mL of cow milk) according to our previous report (Wu et al., 2019, 2022). Briefly, HAV suspension (100 μL) prepared in PBS (pH 7.4) containing 8.3 × 105, 8.3 × 103, 8.3 × 101, or 8.3 × 100 PFU of viral particles were pipetted evenly onto the surface of each solid food sample in a Petri dish with 3 μL inoculated at each spot. The inoculum was dried onto the surface of each solid food by leaving at room temperature for 1 h. As to liquid food matrix (milk), 40 mL of the milk in 50 mL centrifuge tube was inoculated with 100 μL of HAV dilutions (8.3 × 105, 8.3 × 103, 8.3 × 101, or 8.3 × 100 PFU) prepared in PBS (pH 7.4). The artificially contaminated milk was mixed well and then left at room temperature for 1 h. For all foods, each HAV dilution was inoculated onto three independent samples, and one uninoculated sample was used as a negative control. HAV Concentration and RNA Extraction Viral particles on surface of each of the solid foods were eluted using 50 mL of glycine buffer (0.05 M glycine, 0.14 M NaCl, 0.2% (v/v) Tween 20, pH 9.0) according to our previous report (Wu et al., 2022). HAV particles in the liquid milk samples and in the glycine buffer (collected from the solid foods) were captured and concentrated by protamine-coated magnetic nanoparticles (PMNPs) as described previously (Wu et al., 2019, 2022). Viral RNA was extracted from the concentrated samples using the QIAamp MinElute Virus Spin Kit (Cat. No. 57704, Qiagen, Toronto, ON, Canada) according to the manufacturer's instructions. RNA was eluted in 40 μL of RNase-free water (Cat. No. AM9937, Applied Biosystems) and quantified using real-time RT-PCR, RT-LAMP assay, and RT-LAMP-BART assay as described in the sections below. HAV RNA was also extracted from 200 μL of the virus stock containing 8.3 × 106 PFU/mL of virus strain HM175/24A. The RNA was serially diluted in tenfold increments and each dilution was subjected to real-time RT-PCR, RT-LAMP assay, and RT-LAMP-BART assay. Real-Time RT-PCR HAV RNA was reverse transcribed to cDNA using the High-capacity cDNA Reverse Transcription Kit (Cat. No. 4374966, Applied Biosystems) in accordance with the manufacturer’s instructions. The cDNA was quantified by real-time PCR using a ViiA 7 Real-Time PCR system (Applied Biosystems) as described by Wu et al. (2019). The sequence of primer pairs and TaqMan probe are shown in Table 1. A tenfold dilution series of cNDA corresponding to a virus titer ranging from 8.3 × 105 PFU/mL to 8.3 × 100 PFU/mL was used for generation of the standard curve.Table 1 Details of primers used for HAV assays by real-time RT-PCR and RT-LAMP-BART Assay Primer name Primer sequence (5′-3′) Primer position Polarity References Real-time RT-PCR Forward ATAGGGTAACAGCGGCGGATAT 448–469 + Gardner et al. (2003) Reverse CTCAATGCATCCACTGGATGAG 516–537 - Probe FAM-CCATTCAACGCCGGAGG-MGB 492–508 + This study RT-LAMP-BART F3 GCATGGAGCTGTAGGAGTCT 293–312 + Yoneyama et al. (2007) B3 CACTCAATGCATCCACTGGA 520–539 - FIP F1C: ACCCGTAGCCTACCTCTTGTGG F2: TGTTGGGAACGTCACCTTG 385–406 329–347 - + FIP031 F1C: ACCCGTAGCCTACCCCTTGTGG F2: TGTTTGGGACGTCGCCTTG 385–406 329–347 - + BIP B1C: TTGGATAGGGTAACAGCGGCG B2: CTCCGGCGTTGAATG 444–464 493–507 + - FLOOP TGAAAGCCAAGTTAACACTG 348–367 - BLOOP GATATTGGTGAGTTGTTAAGAC 465–486 + FIP and FIP031 primers consisted of F1C plus F2 and BIP primer consisted of B1C plus B2. The different bases between primer FIP and FIP031 are highlighted and underlined. The positions of primers are in accordance with wild-type strain of HAV (GenBank accession number: M14707.1) RT-LAMP Assay The primers used for the RT-LAMP assay of HAV are shown in Table 1. The RT-LAMP assay was performed using the Loopamp RNA Amplification Kit (Cat. No. LMP244, Eiken Chemical Co. Ltd., Tokyo, Japan) according to the manufacturer’s instructions. Briefly, a 25 μL-reaction was composed of 12.5 μL of 2 × reaction mixture, 1 μL of enzyme mixture containing 16 U Bst DNA polymerase and 2 U avian myeloblastosis virus (AMV) reverse transcriptase, 0.8 μM of each of the FIP031 and FIP primer, 1.6 μM of BIP primer, 0.8 μM of each of the FLOOP and BLOOP primer, 0.2 μM of each of the F3 and B3 primer, and 5 μL of extracted RNA. The reaction mixture was incubated using a GeneAmp PCR system 9700 (Applied Biosystems) at 62.5 °C for 60 min, 80 °C for 5 min, and then at 4 °C until further analysis (Yoneyama et al., 2007). One reaction without RNA template was used as a negative control. The RT-LAMP products (3 μL) were resolved on 1% TAE (Cat. No. 161-0743, Bio-Rad Laboratories Ltd.) agarose gel containing 0.1 μg/mL of ethidium bromide (Cat. No. E1510, Sigma-Aldrich) by electrophoresis at 75 V for 50 min, and visualized and photographed over UV light, using an UV transilluminator (Bio-Rad Laboratories Ltd.). One-Step RT-LAMP-BART Assay The RT-LAMP-BART master mix was prepared by adding 187.5 μL of 2 × Lumopol buffer (Lumora Ltd., Ely, Cambridgeshire, UK) to the lyophilized RT-LAMP-BART-master tube (Lumora Ltd., Ely, Cambridgeshire, UK). Each reagent was kept on ice during the operation. Primer mix was prepared using nuclease-free water (Cat. No. AM9937, Life Technologies). The concentration of primers in the primer mix was: 2.1 μM of each of FIP031 and FIP primer, 4.3 μM of BIP primer, 2.1 μM of each of FLOOP and BLOOP primer, and 0.5 μM of each of F3 and B3 primer. Then, equal volumes of the RT-LAMP-BART master mix and primer mix were mixed together. The remaining RT-LAMP-BART master mix was aliquoted and stored at − 150 °C for later use. RT-LAMP-BART reactions were run at 55 °C in 20 μL total volume containing 15 μL of the reagent mix and 5 μL of RNA template. Each sample was run in duplicate. The reactions were performed in a 96-well plate (Cat. No. 14-230-232, Thermo Fisher Scientific). Each reaction was covered with 20 μL of molecular grade mineral oil (Lumora Ltd., Ely, Camridgeshire, UK) to prevent evaporation. The final concentration of primers in each reaction was: 0.8 μM of each of FIP031 and FIP primer, 1.6 μM of BIP primer, 0.8 μM of each of FLOOP and BLOOP primer, and 0.2 μM of each of F3 and B3 primer. The luminescence was tested at 1 min intervals using a Bison system (Lumora Ltd., Cambridgeshire, UK). A standard curve was constructed by analyzing the time-to-peak of the tenfold serial dilutions of the viral RNA. The effect of different concentrations (2 mM, 3 mM, and 4 mM) of MgSO4 on the one-step RT-LAMP-BART reaction efficiency was tested. The effect was tested using two RNA dilutions corresponding to the viral titers of 8.3 × 105 PFU/mL and 8.3 × 103 PFU/mL. Each test was done in three replicates. The efficiency of the reaction using primers purified with high-performance liquid chromatography (HPLC) and cartridge technique was compared. HPLC-purified primers were synthesized by Life Technologies Corporation (Burlington, ON, Canada) and cartridge-purified primers were obtained from Laboratory Services at the University of Guelph (Guelph, ON, Canada). For testing HAV in food samples, the cartridge-purified primers were used for green onions and strawberries, while HPLC-purified primers were used for mussels and milk. Two-Step RT-LAMP-BART Assay The LAMP-BART master mix was prepared by adding 187.5 μL of 2 × Lumopol buffer (Lumora Ltd., Ely, Cambridgeshire, United Kingdom) to the lyophilized LAMP-BART-master tube (Lumora Ltd., Ely, Cambridgeshire, UK) in a similar way as for preparing the RT-LAMP-BART master mix. Then, equal volumes of the LAMP-BART master mix and primer mix were mixed together. LAMP-BART reactions were run at 62 °C in 20 μL total volume containing 15 μL of the reagent mix, 1 μL of nuclease-free water, and 4 μL of cDNA template. Each sample was run in duplicate. Each reaction was covered with 20 μL of molecular grade mineral oil (Lumora Ltd., Ely, Camridgeshire, UK) to prevent evaporation. The final concentration of primers in each reaction was the same as that used for one-step RT-LAMP-BART. The luminescence was tested at 1 min intervals using a Bison system (Lumora Ltd., Cambridgeshire, UK). A standard curve was constructed by analyzing the time-to-peak of the tenfold serial dilutions of HAV cDNA. The effect of different concentrations (0 mM, 2 mM, 3 mM, and 4 mM) of MgSO4 on the two-step RT-LAMP-BART reaction was tested. The effect was tested using two cDNA dilutions corresponding to an initial viral titer of 8.3 × 105 PFU/mL and 8.3 × 103 PFU/mL. Each test was done in three replicates. Statistical Analysis Statistical analysis was performed using one-way analysis of variance (ANOVA) with IBM SPSS Statistics (version 21; IBM Corporation, New York, USA). In all cases, differences were considered significant when the P-value was less than 0.05. Results Real-Time RT-PCR of HAV A real-time RT-PCR was used to amplify tenfold serial dilutions of HAV cDNA. The fluorescence intensity of 6-carboxyfluorescein (FAM) was recorded over time during the amplification of cDNA templates (Fig. 2). The shape of the amplification curve monitored by fluorescence in real-time RT-PCR is different from the amplification curve measured by luminescence in RT-LAMP-BART assay (Figs. 4, 5, 6). The amplification curve for real-time RT-PCR is sigmoidal whereas the curve for BART assay is with an identifiable peak.Fig. 2 Amplification of HAV cDNA in real-time RT-PCR monitored by the measurement of fluorescence (Color figure online) One-Step RT-LAMP Assay of HAV As observed through agarose gel electrophoresis, amplification product of RT-LAMP was with a ladder-like pattern (Fig. 3). This is due to the formation of a mixture of stem-loop DNAs with various stem lengths (Notomi et al., 2000). The detection limit of RT-LAMP assay was 8.3 × 101 PFU/mL, which was higher than that of real-time RT-PCR (8.3 × 100 PFU/mL).Fig. 3 Analysis of RT-LAMP amplicon of HAV RNA by 1% agarose gel electrophoresis. Lane M, 2-log DNA ladder (Cat. No. N0469L, New England Biolab); Lane 1, no template control; Lane 2–7, HAV RNA dilutions corresponding to 8.3 × 105, 8.3 × 104, 8.3 × 103, 8.3 × 102, 8.3 × 101, and 8.3 × 100 PFU/mL of the initial virus titer, respectively Optimization of Mg2+ Concentration in One-Step and Two-Step RT-LAMP-BART Assay The enzymatic reactions of RT-LAMP-BART assay were complicated, as shown in Fig. 1. Optimization of the reaction system is necessary to obtain higher sensitivity. For the tested both RNA dilutions (Fig. 4A, B), the MgSO4 concentration at 2 mM demonstrated the optimal amplification effect on one-step RT-LAMP-BART. It was apparent that the time-to-peak of RT-LAMP-BART reaction performed in the presence of 2 mM MgSO4 was detected earlier than those of the reaction performed with 3 mM or 4 mM MgSO4, indicating that with the increase of Mg2+ concentration, the reaction sensitivity decreased significantly (P < 0.05).Fig. 4 Effect of MgSO4 concentrations on one-step RT-LAMP-BART reaction of HAV. Each curve represents one of three replicates. A RNA was from 8.3 × 105 PFU/mL of HAV; B RNA was from 8.3 × 103 PFU/mL of HAV (Color figure online) As shown in Fig. 5A, B, for both cDNA dilutions, the MgSO4 concentration at 4 mM showed the optimal amplification effect on two-step RT-LAMP-BART. The reaction sensitivity increased significantly (P < 0.05) with the increase of MgSO4 concentration. Within the test time, the MgSO4 concentration of 0 mM failed to produce an amplification signal for the cDNA dilution corresponding to a viral titer of 8.3 × 103 PFU/mL (Fig. 5).Fig. 5 Effect of MgSO4 concentrations on two-step RT-LAMP-BART reaction of HAV. Each curve represents one of three replicates. A cDNA was from 8.3 × 105 PFU/mL of HAV; B cDNA was from 8.3 × 103 PFU/mL of HAV (Color figure online) Comparison of HPLC-Purified and Cartridge-Purified Primers in One-Step RT-LAMP-BART Assay The effect of primers purified with HPLC and cartridge technology on the efficiency of one-step RT-LAMP-BART assay was investigated. It was found that HPLC-purified primers produced more sensitive results than cartridge-purified primers (Fig. 6). As shown in Fig. 6, for each RNA dilution, the time-to-peak of the reaction using HPLC-purified primers was earlier than that of the counterpart reaction using cartridge-purified primers and the difference is statistically significant (P < 0.05).Fig. 6 Comparison of HPLC-purified and cartridge-purified primers in RT-LAMP-BART assay. Four HAV RNA dilutions corresponding to 8.3 × 105, 8.3 × 104, 8.3 × 103, and 8.3 × 102 PFU/mL of the initial virus titer were tested. The orange lines indicate the reactions using HPLC-purified primers. The blue lines indicate the reactions using cartridge-purified primers. Each curve represents one of three replicates (Color figure online) Sensitivity Analysis of One-Step and Two-Step RT-LAMP-BART Assay For one-step RT-LAMP-BART assay, a standard curve constructed by plotting the time-to-peak of the luminescence signal against the logarithm of the concentration of tenfold serial dilutions of virus titer is shown in Fig. 7. The results showed that HAV RNA was detected to at least 10–5 dilution corresponding to 2.1 PFU/reaction of the virus. The values indicated that the concentration of HAV with the titer of 8.3 × 101 PFU/mL could be detected by the one-step RT-LAMP-BART. This limit of detection was the same as that for one-step RT-LAMP and was one log higher than that obtained using real-time RT-PCR (Fig. 2).Fig. 7 Standard curve of one-step RT-LAMP-BART assay generated by testing the time-to-peak of tenfold serial dilutions of HAV RNA. Each value is the mean of three independent replicates. Bars show standard deviation. The assay was performed at 55 °C for 100 min A standard curve for two-step RT-LAMP-BART assay was constructed by plotting the time-to-peak of the luminescence signal against the logarithm of the concentration of the virus titer and is shown in Fig. 8. The results indicated that the virus with a titer as low as 8.3 × 100 PFU/mL, corresponding to 0.083 PFU/reaction, could be detected by the two-step RT-LAMP-BART assay. This limit of detection was the same as that obtained using real-time RT-PCR and was one log lower than that of one-step RT-LAMP-BART assay.Fig. 8 Standard curve of two-step RT-LAMP-BART assay made by testing the time-to-peak of tenfold serial dilutions of HAV cDNA. Each value is the mean of three independent replicates. Bars show standard deviation. The assay was performed at 62 °C for 100 min Comparison of Real-Time RT-PCR, One-Step RT-LAMP-BART, and Two-Step RT-LAMP-BART Assay for the Detection of HAV from Different Foods HAV separated and concentrated from green onions, strawberries, mussels, and milk artificially contaminated with different levels of the viral particles was analyzed using real-time RT-PCR, one-step RT-LAMP-BART, and two-step RT-LAMP-BART assay. The detection limit of the three methods varies according to food type (Table 2). Any food sample uncontaminated with the virus did not give an amplification signal for any of the three detection methods. For green onions, real-time RT-PCR, two-step RT-LAMP-BART, and one-step RT-LAMP-BART assay demonstrated a detection limit of 8.3 × 100 PFU/15 g, 8.3 × 100 PFU/15 g, and 8.3 × 101 PFU/15 g, respectively. For strawberries, both real-time RT-PCR and two-step RT-LAMP-BART were able to detect HAV level as low as 8.3 × 101 PFU/50 g. The one-step RT-LAMP-BART was apparently inferior to the other two methods in terms of detection limit, with virus at the inoculum level of 8.3 × 101 PFU/50 g or 8.3 × 100 PFU/50 g not detectable. As for mussels and milk, all three methods showed a detection limit of 8.3 × 100 PFU/sample.Table 2 Comparison of real-time RT-PCR, one-step RT-LAMP-BART, and two-step RT-LAMP-BART assays in detecting HAV in green onions, strawberries, mussels, and milk Food sample Method No. of positive samples / No. of tested samples at inoculation level (PFU) of 8.3 × 105 8.3 × 103 8.3 × 101 8.3 × 100 Green onion Real-time RT-PCR 6/6 6/6 6/6 4/6 One-step RT-LAMP-BART 6/6 6/6 2/6 0/6 Two-step-RT LAMP-BART 6/6 6/6 2/6 2/6 Strawberry Real-time RT-PCR 6/6 6/6 6/6 0/6 One-step RT-LAMP-BART 6/6 4/6 0/6 0/6 Two-step-RT LAMP-BART 6/6 6/6 4/6 0/6 Mussel Real-time RT-PCR 6/6 6/6 4/6 2/6 One-step RT-LAMP-BART 6/6 6/6 4/6 4/6 Two-step-RT LAMP-BART 6/6 6/6 2/6 2/6 Milk Real-time RT-PCR 6/6 6/6 4/6 2/6 One-step RT-LAMP-BART 6/6 6/6 6/6 6/6 Two-step-RT LAMP-BART 6/6 6/6 6/6 2/6 For each food, virus was recovered on three distinct occasions and detection of viral RNA by real-time RT-PCR, one-step RT-LAMP-BART, and two-step RT-LAMP-BART was performed in duplicate resulting in six determinations for each load of virus. Virus inoculum level per food sample was 8.3 × 105 PFU, 8.3 × 103 PFU, 8.3 × 101 PFU, or 8.3 × 100 PFU. The RT-LAMP-BART assay was performed for 130 min Discussion Molecular techniques based on the amplification of genomic DNA/RNA of microorganisms have been used for the specific and sensitive detection of pathogens in foods. The most widely used detection method is real-time PCR, a technique developed in the early 1990s (VanGuilder et al., 2008). Since its invention, this technique has been improved dramatically. For example, different real-time chemistries have been used (e.g., SYBR green-based and TaqMan-based detection), different formats of the instrument have been developed (e.g., ABI 7900HT, ViiA 7, and QuantStudio real-time PCR system), and the master mix used in the technique has been optimized to minimize the amplification time and enhance tolerance to inhibitors. In spite of so much improvement, this technique requires sophisticated equipment and is expensive, making it impractical to be applied in resource-limited settings. Therefore, there is a rapidly increasing demand for more affordable alternatives providing speed, simplicity, accuracy, and robustness in both molecular assay and the equipment for detecting foodborne pathogens (e.g., HAV). As an alternative to PCR technology strictly requiring a sophisticated thermal cycler and fluorescence excitation and emission measurement equipment, LAMP reaction is conducted at a constant temperature, negating the need for a thermocycler. Because of its simplicity, this technique has provided a very convenient way for the detection of organisms including bacteria, viruses, fungi, parasites, animals, and plants (Aartse et al., 2017; Focke et al., 2013; Lalle et al., 2018; Li et al., 2017; Niessen et al., 2013; Parida et al., 2004; Sheu et al., 2018). Since its invention in 2000 (Notomi et al., 2000), this technique has also been improved dramatically. For example, conventional LAMP assay that was based on gel electrophoresis of the amplification products has been upgraded to real-time detection of the turbidity of magnesium pyrophosphate (Mori et al., 2004), of the fluorescence of chelating reagents (Tomita et al., 2008), or of the bioluminescence generated from PPi (Gandelman et al., 2010). The LAMP assay coupled with the detection of bioluminescence was named LAMP-BART in 2010 (Gandelman et al., 2010) and has shown great performance in detecting Chlamydia trachomatis (Gandelman et al., 2010), classical swine fever virus (Gandelman et al., 2010), genetically modified maize (Kiddle et al., 2012), human parvovirus B19 (Mirasoli et al., 2018), and SARS-CoV-2 (Fei et al., 2021). The optimization of reaction system is essential in achieving detection sensitivity. We optimized Mg2+ concentration in the current study to improve the sensitivity of RT-LAMP-BART assay. The concentration of Mg2+ has also been optimized in previous studies. Liu et al. (2013) found that 5.75 mM of Mg2+ was optimal in detection of Leifsonia xyli subsp. xyli in sugarcane using LAMP. Liu et al. (2011) reported that the optimal concentration of Mg2+ in using LAMP to detect Bacillus cereus in milk was 2 mM. Nie (2005) reported that 6–8 mM of Mg2+ were optimal in detecting Potato virus Y using LAMP. Aside from Mg2+ concentration, other factors influencing the sensitivity of LAMP reaction, such as primer concentration, dNTP (deoxyribonucleotide triphosphate) concentration, enzyme concentration, reaction temperature, and reaction time, were also optimized in these studies. However, Mg2+ concentration was found to be the most critical factor when optimizing LAMP reaction (Liu et al., 2011, 2013). The concentration of Mg2+ is important to the RT-LAMP-BART reaction because Mg2+ serves the cofactor of the enzymes used in the RT-LAMP-BART assay, such as reverse transcriptase, Bst polymerase, ATP sulfurylase, and luciferase (Cowan, 2002). ATP can only become active upon binding with Mg2+ (Cowan, 2002; Nakatsu et al., 2006), increasing the production of luminescence. Thus, inadequate Mg2+ in the reaction could lead to inactive enzymes and ATP and hence slow down chemical reaction rates. On the other hand, too much Mg2+ can bring many drawbacks to chemical reactions in RT-LAMP-BART, such as decreasing fidelity and specificity of DNA polymerase, interfering with complete denaturation of DNA strands during amplification, leading to primers annealing to incorrect sites of DNA template and causing nonspecific amplified products, as well as inhibiting DNA amplification through chelation by dNTPs (Goto et al., 2009; Kuffel et al., 2021). In this study, 2 mM Mg2+ and 4 mM Mg2+ was the optimal concentration for one-step RT-LAMP-BART and two-step RT-LAMP-BART, respectively. In the current study, the primers used in RT-LAMP-BART and real-time RT-PCR for the detection of HAV were selected from the same conserved region (5’-UTR) of HAV genome. The specificity of primers used in LAMP for HAV detection has been examined by testing several genotypes of HAV and other enteric viruses, and they only amplify HAV target sequences (Yoneyama et al., 2007). For LAMP primers, the inner primers generate hairpin loops, and the outer primers displace the DNA strands. Aside from inner and outer primers, the use of loop primers (Nagamine et al., 2002) or stem primers (Gandelman et al., 2011) could accelerate the speed of amplification, and improve sensitivity of the reaction. We found that the sensitivity of the assay could also be improved by primer quality. HPLC-purified primers were used in some reports (Luo et al., 2011; Yang et al., 2011), and there were others using cartridge-purified primers (Yoda et al., 2007) in the LAMP assay. By comparing the results from HPLC-purified and cartridge-purified primers, we found that HPLC-purified primers demonstrated improved sensitivity of RT-LAMP-BART reaction. For primer synthesis, the longer the sequence, the higher the error rate and a larger number of failed truncated sequences are produced. HPLC can not only remove impurities such as salt and organic solvent, but also eliminate truncated sequences to a greater extent than cartridge purification technique, producing primers with higher yield and purity (Biolegio, https://www.biolegio.com/products-services/purification/). The inner primers (~ 40 bases) used in LAMP reaction are at least twice as long as the primers (~ 20 bases) used in PCR. HPLC technique could guarantee the lower error rate in inner primer sequences. Hardinge et al. (2018) reported that primer quality significantly affected the amplification performance of LAMP-BART assay in detection of DNA from genetically modified maize. They concluded that using HPLC-purified primers was very important because they could especially give reliable amplification of low copy number of DNA in a reaction. The sensitivity of one-step and two-step RT-LAMP-BART assay were measured by testing tenfold serial dilutions of RNA obtained from a viral stock or cDNA. It was found that the limit of detection of two-step RT-LAMP-BART and one-step RT-LAMP-BART was 0.083 PFU/reaction and 2.1 PFU/reaction of HAV, respectively. The two-step RT-LAMP-BART showed higher sensitivity than one-step RT-LAMP-BART. The amplification temperature for LAMP assay is usually between 60 and 65 °C (Kokkinos et al., 2014). In the current study, the amplification temperature for two-step RT-LAMP-BART was 62 °C, but for one-step RT-LAMP-BART, the amplification temperature was 55 °C. This is because the reverse transcriptase in the RT-LAMP-BART-master developed by Lumora Ltd. was not stable above 60 °C. This lower amplification temperature might contribute to the lower sensitivity of the one-step RT-LAMP-BART in our experiment. The sensitivity of two-step RT-LAMP-BART and real-time RT-PCR used in our study were the same: 0.083 PFU/reaction, corresponding to the virus titer of 8.3 × 100 PFU/mL. Compared with the limited published data, the value was lower than the 0.5 PFU/reaction reported by Jothikumar et al. (2005) who used TaqMan real-time PCR, lower than 1 PFU/reaction reported by El Galil et al. (2004) for using molecular-beacon real-time RT-PCR, lower than 2 PFU/reaction reported by Jean et al. (2002) for using nucleic acid sequence-based amplification (NASBA) method, and lower than 0.1 PFU/reaction reported by Hu and Arsov (2014) for using nested real-time PCR for the detection of HAV RNA. HAV seeded on green onions, strawberries, mussels, or in milk, was detected using real-time RT-PCR, one-step RT-LAMP-BART and two-step RT-LAMP-BART. The sensitivities of two-step RT-LAMP-BART and real-time RT-PCR were comparable in testing HAV in each food (Table 2). One-step RT-LAMP-BART assay showed better performance in testing HAV in mussels and milk than in green onions and strawberries, which might be due to the fact that primers purified with different methods were used when detecting HAV in different foods. The cartridge-purified primers were used for testing HAV in green onions and strawberries, while HPLC-purified primers were used for testing the virus in mussels and milk. For strawberries, HAV at an inoculum level of 8.3 × 100 PFU/50 g was not detectable by any of the three methods, which might be due to the low efficiency of the virus separation and concentration step or the strong inhibition of the reactions from strawberry compounds. The detection limit of RT-LAMP-BART assay developed in the current study may be able to satisfy the need for diagnostic purpose, because HAV infectious dose is presumably between 10 and 100 viral particles and the contamination level of virus is low in food (Sánchez et al., 2007; Yezli & Otter, 2011). The detection limit of HAV in different foods obtained in our study using PMNP separation and concentration method coupled with RT-LAMP-BART is comparable with or better than that reported by other research groups using different virus detection methods (Table 3).Table 3 Detection limit of HAV in different foods using different detection methods Food Detection method Detection limit Reference Green onion Real-time RT-PCR 102 PFU/25 g Zheng and Hu (2017) Green onion RT-PCR 1 TCID50 (approximately 1.4 PFU)/25 g Guevremont et al. (2006) Green onion Nested real-time PCR 1 PFU/25 g Hu and Arsov (2014) Green onion Real-time RT-PCR Not determined Lowther et al. (2019) Green onion RT-LAMP-BART 8.3 × 100 PFU/15 g This study Strawberry RT-PCR 104 RT-PCR unit/90 g Rzezutka et al. (2006) Strawberry Real-time RT-PCR 1.2 TCID50 (approximately 1.7 PFU)/15 g Butot et al. (2007) Strawberry RT-LAMP-BART 8.3 × 101 PFU/50 g (10 RT-PCR unit/50 g) This study Shellfish Real-time RT-PCR 100 TCID50 (approximately 1.4 PFU)/1.5 g Ko et al. (2018) Shellfish RT-PCR 100 TCID50 (approximately 1.4 PFU)/1 g Ko et al. (2015) Shellfish RT-PCR 1.5 PFU/3.75 g Kingsley and Richards (2001) Shellfish Real-time RT-PCR 25 TCID50 (approximately 35 PFU)/25 g Casas et al. (2007) Shellfish Real-time RT-PCR Not determined Lowther et al. (2019) Shellfish RT-LAMP-BART 8.3 × 100 PFU/5 g This study Milk RT-LAMP-BART 8.3 × 100 PFU/40 mL This study The amplification time of the RT-LAMP-BART (130 min) was longer than that of real-time RT-PCR (40 min) used in the current study. The reaction system for PCR, including reagents and instrument, has been improved considerably since the method was invented. For example, in our previous study, we used ABI 7900HT Fast Real-Time PCR System coupled with Absolute QPCR ROX mix to detect HAV (Wu et al., 2022). The amplification time was 100 min with the use of this system, while the amplification time was reduced to 40 min with the application of ViiA 7 system and TaqMan Fast Advanced Master Mix (Wu et al., 2022). RT-LAMP-BART assay is a relatively novel technology and the amplification time can also be reduced through optimizing the reaction conditions, such as the master mix and equipment. It was reported that the LAMP amplification time could be reduced by about 50% when the new Bst 2.0 or Bst 2.0 WarmStart DNA polymerase was used (Tanner et al., 2012) compared to the use of the wild-type Bst DNA polymerase. In future, the components of the master mix used for the RT-LAMP-BART reaction may be optimized to further improve the sensitivity, speed, and robustness of the method. The RT-LAMP-BART assay has several advantages over real-time RT-PCR. The instrument used for RT-LAMP-BART and the software used for data interpretation are simple, because RT-LAMP-BART relies on the time-to-peak of light output not the absolute light intensity (Gandelman et al., 2010). An instrument containing a heating block capable of controlling temperature and a photodiode or a charge-coupled device (CCD) camera for detecting light can satisfy the requirements of the method (Gandelman et al., 2010). Real-time PCR is based on the detection of absolute fluorescence intensity during a thermal cycling reaction and requires an instrument consisting of a light-emitting diode (LED) for emitting a broad spectrum of light, filters for selecting the excitation and emission wavelength of specific fluorophores, mirrors for reflecting light, a photodiode, CCD or photomultiplier tube for detecting emitted light, and a device for heating and cooling the reaction plate. The instrument can only be operated by trained personnel and needs to be calibrated frequently to guarantee accurate experimental results. Instead, any person can operate the Bison system (Lumora Ltd.) used for RT-LAMP-BART assay after a short training session and the maintenance of the instrument is simple and easy. The instrument software used for real-time PCR protocol setup, data collection, and data analysis are much more complicated than that for RT-LAMP-BART. Moreover, due to the isothermal characteristic of the reaction, the RT-LAMP-BART instrument has the potential to be miniaturized to become a portable device that is suited for field applications. But PCR can only be applied in the laboratory and not on-site. Various formats of portable devices have been designed to perform the LAMP reaction in remote areas where resources are limited. A portable ESE Quant tube scanner has been used for detection of fluorescence signal of SYBR Green I in the amplification of the genome of Vibrio parahaemolyticus and malaria using LAMP (Lucchi et al., 2010; Surabattula et al., 2013; Yi et al., 2014). It was also reported that the LAMP reaction could be performed on a silicon chip for the detection of virulence genes of Listeria monocytogenes, Escherichia coli, and Salmonella (Duarte et al., 2013). Microfludic devices have also been developed for the detection of foodborne pathogens such as Campylobacter jejuni, Shigella, Salmonella Typhimurium, and Vibrio cholerae using the LAMP technique (Hsieh et al., 2012; Tourlousse et al., 2012). All these portable devices are based on fluorescence detection. The portable device for RT-LAMP-BART will be easier to design because luminescence detection is much simpler than fluorescence. Lumora Ltd. has manufactured a portable instrument capable of testing eight samples at one time to enable the RT-LAMP-BART technique to be performed in the field (Kiddle et al., 2012). Song et al. (2018) designed a smartphone-based mobile detection platform for rapid detection of Zika virus in urine and saliva and HIV in blood using BART-LAMP technology. The platform is suitable for use at home and in the field. With the great potential of pathogen specific and ready-to-use reagent (e.g., detection kit) to be developed and the applicability of less expensive and easy-to-use portable devices, the RT-LAMP-BART technique is a promising new tool in detection of foodborne pathogens (e.g., HAV) in future. In conclusion, RT-LAMP-BART showed good performance in the detection of HAV concentrated from different foods including green onions, strawberries, mussels, and milk in the current study. The developed methods need to be compared with the procedures in ISO 15216 for foodborne HAV detection in future. RT-LAMP-BART showed comparable sensitivity with real-time RT-PCR for detecting HAV in different foods. The reaction time of the RT-LAMP-BART may be dramatically reduced through optimizing the master mix in the future. The short testing time in combination with the miniaturized simple instruments may make this technique very powerful in detection of foodborne pathogens. Acknowledgements The authors gratefully acknowledge the research funding provided by Ontario Ministry of Agriculture, Food & Rural Affairs (OMAFRA). The authors wish to thank Prof. Eva Nagy and Dr. Li Deng at Department of Pathobiology, University of Guelph, for their technical assistance in HAV plaque assay, Dr. Rocio Morales-Rayas at Canadian Research Institute for Food Safety (CRIFS) for her assistance in real-time PCR, and Dr. Hany Anany and Dr. Lubov Brovko at CRIFS for their assistance in BART-LAMP. The authors also extend our appreciation to Lumora Ltd. for scientific equipment. Funding Funding was provided by Ontario Ministry of Agriculture, Food and Rural Affairs (Grant Number FS080739). Data Availability The data used to support the findings of this study are provided in full in the results section of this paper. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Aartse A Scholtens IMJ Boersma-Greve, M. M., Prins, T. W., van Ginkel, L. A., Kok, E. J., & Bovee, T. F. H. Evaluation of a loop-mediated isothermal amplification (LAMP) method for rapid on-site detection of horse meat Food Control 2017 81 9 15 10.1016/j.foodcont.2017.05.025 Abdulmawjood A Grabowski N Fohler S Kittler S Nagengast H Klein G Development of loop-mediated isothermal amplification (LAMP) assay for rapid and sensitive identification of ostrich meat PLoS ONE 2014 9 6 e100717 10.1371/journal.pone.0100717 24963709 Ahmad F Seyrig G Tourlousse DM Stedtfeld RD Tiedje JM Hashsham SA A CCD-based fluorescence imaging system for real-time loop-mediated isothermal amplification-based rapid and sensitive detection of waterborne pathogens on microchips Biomedical Microdevices 2011 13 5 929 937 10.1007/s10544-011-9562-2 21720851 Amaral, C., Antunes, W., Moe, E., Duarte, A. G., Lima, L. M., Santos, C., Gomes, I. L., Afonso, G. S., Vieira, R., & Teles, H. S. S. J. S. R. (2021). A molecular test based on RT-LAMP for rapid, sensitive and inexpensive colorimetric detection of SARS-CoV-2 in clinical samples. Scientific Reports, 11(1), 1–12. Bhaskar, S. V. (2017). Foodborne diseases—Disease burden. In R. K. Gupta, Dudeja, & M. Singh (Eds.), Food Safety in the 21st Century (pp. 1–10). San Diego. Biolegio. Oligo purification. https://www.biolegio.com/products-services/purification/ . Bosch A Gkogka E Le Guyader FS Loisy-Hamon F Lee A van Lieshout L Marthi B Myrmel M Sansom A Schultz AC Winkler A Zuber S Phister T Foodborne viruses: Detection, risk assessment, and control options in food processing International Journal of Food Microbiology 2018 285 110 128 10.1016/j.ijfoodmicro.2018.06.001 30075465 Butot S Putallaz T Sanchez G Procedure for rapid concentration and detection of enteric viruses from berries and vegetables Applied and Environmental Microbiology 2007 73 1 186 192 10.1128/AEM.01248-06 17085706 Cao X Zhao L Zhang J Chen X Shi L Fang X Xie H Chang Y Wang L Detection of viable but nonculturable Vibrio parahaemolyticus in shrimp samples using improved real-time PCR and real-time LAMP methods Food Control 2019 103 145 152 10.1016/j.foodcont.2019.04.003 Casas N Amarita F de Maranon IM Evaluation of an extracting method for the detection of hepatitis A virus in shellfish by SYBR-Green real-time RT-PCR International Journal of Food Microbiology 2007 120 1–2 179 185 10.1016/j.ijfoodmicro.2007.01.017 17900731 Cheftel JC Hefnawy M Emerging risks related to food technology Advances in food protection 2011 Dordrecht 223 254 Cowan JA Structural and catalytic chemistry of magnesium-dependent enzymes BioMetals 2002 15 3 225 235 10.1023/A:1016022730880 12206389 Di Cola G Fantilli AC Pisano MB Ré VE Foodborne transmission of hepatitis A and hepatitis E viruses: A literature review International Journal of Food Microbiology 2021 338 108986 10.1016/j.ijfoodmicro.2020.108986 33257099 Duarte C Salm E Dorvel B Reddy B Bashir R On-chip parallel detection of foodborne pathogens using loop-mediated isothermal amplification Biomedical Microdevices 2013 15 5 821 830 10.1007/s10544-013-9769-5 23620454 EFSA Tracing of food items is connection to the multinational hepatitis A virus outbreak in Europe EFSA Journal 2014 12 9 3821 El Galil KHA El Sokkary MA Kheira SM Salazar AM Yates MV Chen W Mulchandani A Combined immunomagnetic separation-molecular beacon-reverse transcription-PCR assay for detection of hepatitis A virus from environmental samples Applied and Environmental Microbiology 2004 70 7 4371 4374 10.1128/AEM.70.7.4371-4374.2004 15240322 Fei Z Wei R Cheng C Xiao P A novel approach to the bioluminescent detection of the SARS-CoV-2 ORF1ab gene by coupling isothermal RNA reverse transcription amplification with a digital PCR approach International Journal of Molecular Sciences 2021 22 3 1017 10.3390/ijms22031017 33498408 Ferrara M Perrone G Gallo A Epifani F Visconti A Susca A Development of loop-mediated isothermal amplification (LAMP) assay for the rapid detection of Penicillium nordicum in dry-cured meat products International Journal of Food Microbiology 2015 202 42 47 10.1016/j.ijfoodmicro.2015.02.021 25771218 Fleet GH Heiskanen P Reid I Buckle KA Foodborne viral illness—Status in Australia International Journal of Food Microbiology 2000 59 1 127 136 10.1016/S0168-1605(00)00249-X 10946844 Focke F Haase I Fischer M Loop-mediated isothermal amplification (LAMP): Methods for plant species identification in food Journal of Agricultural and Food Chemistry 2013 61 12 2943 2949 10.1021/jf304295b 23432417 Francois P Tangomo M Hibbs J Bonetti EJ Boehme CC Notomi T Perkins MD Schrenzel J Robustness of a loop-mediated isothermal amplification reaction for diagnostic applications Fems Immunology and Medical Microbiology 2011 62 1 41 48 10.1111/j.1574-695X.2011.00785.x 21276085 Frisch LM Niessen L Development and optimization of a group-specific loop-mediated isothermal amplification (LAMP) assay for the detection of patulin-producing Penicillium species International Journal of Food Microbiology 2019 298 20 30 10.1016/j.ijfoodmicro.2019.03.010 30903915 Gandelman OA Church VL Moore CA Kiddle G Carne CA Parmar S Jalal H Tisi LC Murray JAH Novel bioluminescent quantitative detection of nucleic acid amplification in real-time PLoS ONE 2010 5 11 e14155 10.1371/journal.pone.0014155 21152399 Gandelman O Jackson R Kiddle G Tisi L Loop-mediated amplification accelerated by stem primers International Journal of Molecular Sciences 2011 12 12 9108 9124 10.3390/ijms12129108 22272122 Gardner SN Kuczmarski TA Vitalis EA Slezak TR Limitations of TaqMan PCR for detecting divergent viral pathogens illustrated by hepatitis A, B, C, and E viruses and human immunodeficiency virus Journal of Clinical Microbiology 2003 41 6 2417 2427 10.1128/JCM.41.6.2417-2427.2003 12791858 Girish PS Barbuddhe SB Kumari A Rawool DB Karabasanavar S Muthukumar M Vaithiyanathan S Rapid detection of pork using alkaline lysis- Loop Mediated Isothermal Amplification (AL-LAMP) technique Food Control 2020 110 107015 10.1016/j.foodcont.2019.107015 Goto M Honda E Ogura A Nomoto A Hanaki KI Colorimetric detection of loop-mediated isothermal amplification reaction by using hydroxy naphthol blue BioTechniques 2009 46 3 167 172 10.2144/000113072 19317660 Guevremont E Brassard J Houde A Simard C Trottier YL Development of an extraction and concentration procedure and comparison of RT-PCR primer systems for the detection of hepatitis A virus and norovirus GII in green onions Journal of Virological Methods 2006 134 1–2 130 135 10.1016/j.jviromet.2005.12.009 16423413 Hardinge P Baxani DK McCloy T Murray JA Castell OK Bioluminescent detection of isothermal DNA amplification in microfluidic generated droplets and artificial cells Scientific Reports 2020 10 1 1 14 10.1038/s41598-020-78996-7 31913322 Hardinge P Kiddle G Tisi L Murray JA Optimised LAMP allows single copy detection of 35Sp and NOSt in transgenic maize using Bioluminescent Assay in Real Time (BART) Scientific Reports 2018 8 1 1 17 10.1038/s41598-018-36207-4 29311619 Hsieh KW Patterson AS Ferguson BS Plaxco KW Soh HT Rapid, sensitive, and quantitative detection of pathogenic DNA at the point of care through microfluidic electrochemical quantitative loop-mediated isothermal amplification Angewandte Chemie-International Edition 2012 51 20 4896 4900 10.1002/anie.201109115 22488842 Hu X Collier MG Xu F Hepatitis A outbreaks in developed countries: Detection, control, and prevention Foodborne Pathogens and Disease 2020 17 3 166 171 10.1089/fpd.2019.2648 31829731 Hu Y Arsov I A rapid single-tube protocol for HAV detection by nested real-time PCR Food and Environmental Virology 2014 6 3 189 195 10.1007/s12560-014-9152-6 24902810 ISO. (2019). Microbiology of the food chain—Horizontal method for determination of hepatitis A virus and norovirus using real-time RT-PCR - Part 2: Method for detection. ISO 15216–2:2019. International Organization for Standardization, Geneva. Jean J Blais B Darveau A Fliss I Simultaneous detection and identification of hepatitis A virus and rotavirus by multiplex nucleic acid sequence-based amplification (NASBA) and microtiter plate hybridization system Journal of Virological Methods 2002 105 1 123 132 10.1016/S0166-0934(02)00096-4 12176149 Jothikumar N Cromeans TL Sobsey MD Robertson BH Development and evaluation of a broadly reactive TaqMan assay for rapid detection of hepatitis A virus Applied and Environmental Microbiology 2005 71 6 3359 3363 10.1128/AEM.71.6.3359-3363.2005 15933042 Kaneko H Kawana T Fukushima E Suzutani T Tolerance of loop-mediated isothermal amplification to a culture medium and biological substances Journal of Biochemical and Biophysical Methods 2007 70 3 499 501 10.1016/j.jbbm.2006.08.008 17011631 Kannan, P., Ruban, W., & Quintoil, M. (2020). Foodborne pathogens and nanoparticles as a tool for quality assurance and intervention of foodborne pathogens. In M. N. Khalaf, M. O. Smirnov, P. K., & A. K. Haghi (Eds.), Environmental technology and engineering techniques basic concepts and health interventions (1st ed., pp. 133–153). New York. Kiddle G Hardinge P Buttigieg N Gandelman O Pereira C McElgunn CJ Rizzoli M Jackson R Appleton N Moore C Tisi LC Murray JAH GMO detection using a bioluminescent real time reporter (BART) of loop mediated isothermal amplification (LAMP) suitable for field use BMC Biotechnology 2012 12 15 10.1186/1472-6750-12-15 22546148 Kingsley DH Richards GP Rapid and efficient extraction method for reverse transcript ion-PCR detection of hepatitis A and norwalk-like viruses in shellfish Applied and Environmental Microbiology 2001 67 9 4152 4157 10.1128/AEM.67.9.4152-4157.2001 11526018 Ko SM Cho SY Oh MJ Kwon J Vaidya B Kim D Application of concanavalin A-linked magnetic beads for the detection of hepatitis A virus Journal of Food Protection 2018 81 12 1997 2002 10.4315/0362-028X.JFP-18-218 30476442 Ko SM Vaidya B Kwon J Lee HM Oh MJ Shin TS Cho SY Kim D Detection of hepatitis A virus in seeded oyster digestive tissue by ricin A-linked magnetic separation combined with reverse transcription PCR Journal of Food Protection 2015 78 5 1046 1051 10.4315/0362-028X.JFP-14-540 25951406 Kokkinos PA Ziros PG Bellou M Vantarakis A Loop-mediated isothermal amplification (LAMP) for the detection of Salmonella in food Food Analytical Methods 2014 7 2 512 526 10.1007/s12161-013-9748-8 Kuffel A Gray A Daeid NN Impact of metal ions on PCR inhibition and RT-PCR efficiency International Journal of Legal Medicine 2021 135 1 63 72 10.1007/s00414-020-02363-4 32621147 Kumari S Kumar RR Mendiratta SK Kumar D Kumar A Kumar D Rana P Jawla J On-site detection of tissues of buffalo origin by loop-mediated isothermal amplification (LAMP) assay targeting mitochondrial gene sequences Food Analytical Methods 2020 13 5 1060 1068 10.1007/s12161-020-01718-2 Lalle M Possenti A Dubey JP Pozio E Loop-mediated isothermal amplification-lateral-flow dipstick (LAMP-LFD) to detect Toxoplasma gondii oocyst in ready-to-eat salad Food Microbiology 2018 70 137 142 10.1016/j.fm.2017.10.001 29173620 Li, Q. C., Fang, J. H., Liu, X., Xi, X., Li, M. J., Gong, Y. F., & Zhang, M. Z. (2013). Loop-mediated isothermal amplification (LAMP) method for rapid detection of cry1Ab gene in transgenic rice (Oryza sativa L.). European Food Research and Technology, 236(4), 589–598. Li YM Fan PH Zhou SS Zhang L Loop-mediated isothermal amplification (LAMP): A novel rapid detection platform for pathogens Microbial Pathogenesis 2017 107 54 61 10.1016/j.micpath.2017.03.016 28323152 Liu, J., Xu, L. P., Guo, J. L., Chen, R. K., Grisham, M. P., & Que, Y. X. (2013). Development of loop-mediated isothermal amplification for detection of Leifsonia xyli subsp xyli in sugarcane. Biomed Research International, 357692. Liu ZG Fang GL Li Q Zhou GP Li R Fu YJ Li H Qu S Detection of Bacillus cereus containing voitoxin in food by loop-mediated isothermal amplification method Journal of Food Safety 2011 31 3 313 319 10.1111/j.1745-4565.2011.00302.x Lowther JA Bosch A Butot S Ollivier J Mäde D Rutjes SA Hardouin G Lombard B in't Veld, P., & Leclercq, A. Validation of EN ISO method 15216 - Part 1—Quantification of hepatitis A virus and norovirus in food matrices International Journal of Food Microbiology 2019 288 82 90 10.1016/j.ijfoodmicro.2017.11.014 29229293 Lucchi NW Demas A Narayanan J Sumari D Kabanywanyi A Kachur SP Barnwell JW Udhayakumar V Real-time fluorescence loop mediated isothermal amplification for the diagnosis of malaria PLoS ONE 2010 5 10 e13733 10.1371/journal.pone.0013733 21060829 Luo L Nie K Yang MJ Wang M Li J Zhang C Liu HT Ma XJ Visual detection of high-risk human Papillomavirus genotypes 16, 18, 45, 52, and 58 by loop-mediated isothermal amplification with hydroxynaphthol blue dye Journal of Clinical Microbiology 2011 49 10 3545 3550 10.1128/JCM.00930-11 21865423 Mao R Xie K Zhao M Li MJ Lu L Liu Y Wu Q Chen Y Zhang T Diao E Development and evaluation of a loop-mediated isothermal amplification (LAMP) assay for rapid detection of pistachio (Pistacia vera) in food samples Food Analytical Methods 2020 13 3 658 666 10.1007/s12161-019-01684-4 Mei X Zhai X Lei C Ye X Kang Z Wu X Xiang R Wang Y Wang H Development and application of a visual loop-mediated isothermal amplification combined with lateral flow dipstick (LAMP-LFD) method for rapid detection of Salmonella strains in food samples Food Control 2019 104 9 19 10.1016/j.foodcont.2019.04.014 Mirasoli M Bonvicini F Lovecchio N Petrucci G Zangheri M Calabria D Costantini F Roda A Gallinella G Caputo D de Cesare G Nascetti A On-chip LAMP-BART reaction for viral DNA real-time bioluminescence detection Sensors and Actuators b: Chemical 2018 262 1024 1033 10.1016/j.snb.2018.02.086 Mori Y Kitao M Tomita N Notomi T Real-time turbidimetry of LAMP reaction for quantifying template DNA Journal of Biochemical and Biophysical Methods 2004 59 2 145 157 10.1016/j.jbbm.2003.12.005 15163526 Mori Y Notomi T Loop-mediated isothermal amplification (LAMP): A rapid, accurate, and cost-effective diagnostic method for infectious diseases Journal of Infection and Chemotherapy 2009 15 2 62 69 10.1007/s10156-009-0669-9 19396514 Nagamine K Hase T Notomi T Accelerated reaction by loop-mediated isothermal amplification using loop primers Molecular and Cellular Probes 2002 16 3 223 229 10.1006/mcpr.2002.0415 12144774 Nakatsu T Ichiyama S Hiratake J Saldanha A Kobashi N Sakata K Kato H Structural basis for the spectral difference in luciferase bioluminescence Nature 2006 440 7082 372 376 10.1038/nature04542 16541080 Nie XZ Reverse transcription loop-mediated isothermal amplification of DNA for detection of Potato virus Y Plant Disease 2005 89 6 605 610 10.1094/PD-89-0605 30795385 Niessen L Luo J Denschlag C Vogel RF The application of loop-mediated isothermal amplification (LAMP) in food testing for bacterial pathogens and fungal contaminants Food Microbiology 2013 36 2 191 206 10.1016/j.fm.2013.04.017 24010598 Njiru ZK Yeboah-Manu D Stinear TP Fyfe JAM Rapid and sensitive detection of Mycobacterium ulcerans by use of a loop-mediated isothermal amplification test Journal of Clinical Microbiology 2012 50 5 1737 1741 10.1128/JCM.06460-11 22357495 Notomi T Okayama H Masubuchi H Yonekawa T Watanabe K Amino N Hase T Loop-mediated isothermal amplification of DNA Nucleic Acids Research 2000 28 12 e63 10.1093/nar/28.12.e63 10871386 Ou SC Giambrone JJ Macklin KS Comparison of a TaqMan real-time polymerase chain reaction assay with a loop-mediated isothermal amplification assay for detection of Gallid herpesvirus 1 Journal of Veterinary Diagnostic Investigation 2012 24 1 138 141 10.1177/1040638711427578 22362944 Parida M Posadas G Inoue S Hasebe F Morita K Real-time reverse transcription loop-mediated isothermal amplification for rapid detection of West Nile virus Journal of Clinical Microbiology 2004 42 1 257 263 10.1128/JCM.42.1.257-263.2004 14715762 Rzezutka A D'Agostino M Cook N An ultracentrifugation-based approach to the detection of hepatitis A virus in soft fruits International Journal of Food Microbiology 2006 108 3 315 320 16497401 Sánchez G Bosch A Pintó RM Hepatitis A virus detection in food: Current and future prospects Letters in Applied Microbiology 2007 45 1 1 5 10.1111/j.1472-765X.2007.02140.x 17594452 Sánchez G Pintó RM Vanaclocha H Bosch A Molecular characterization of hepatitis A virus isolates from a transcontinental shellfish-borne outbreak Journal of Clinical Microbiology 2002 40 11 4148 4155 10.1128/JCM.40.11.4148-4155.2002 12409389 Sheu SC Tsou PC Lien YY Lee MS Development of loop-mediated isothermal amplification (LAMP) assays for the rapid detection of allergic peanut in processed food Food Chemistry 2018 257 67 74 10.1016/j.foodchem.2018.02.124 29622231 Song J Pandian V Mauk MG Bau HH Cherry S Tisi LC Liu C Smartphone-based mobile detection platform for molecular diagnostics and spatiotemporal disease mapping Analytical Chemistry 2018 90 7 4823 4831 10.1021/acs.analchem.8b00283 29542319 Surabattula R Vejandla MP Mallepaddi PC Faulstich K Polavarapu R Simple, rapid, inexpensive platform for the diagnosis of malaria by loop mediated isothermal amplification (LAMP) Experimental Parasitology 2013 134 3 333 340 10.1016/j.exppara.2013.03.031 23562879 Tanner NA Zhang YH Evans TC Simultaneous multiple target detection in real-time loop-mediated isothermal amplification BioTechniques 2012 53 2 81 89 10.2144/0000113902 23030060 Tao ZY Zhou HY Xia H Xu S Zhu HW Culleton RL Han ET Lu F Fang Q Gu YP Liu YB Zhu GD Wang WM Li JL Cao J Gao Q Adaptation of a visualized loop-mediated isothermal amplification technique for field detection of Plasmodium vivax infection Parasites & Vectors 2011 4 115 10.1186/1756-3305-4-115 21693031 Tomita N Mori Y Kanda H Notomi T Loop-mediated isothermal amplification (LAMP) of gene sequences and simple visual detection of products Nature Protocols 2008 3 5 877 882 10.1038/nprot.2008.57 18451795 Tourlousse DM Ahmad F Stedtfeld RD Seyrig G Tiedje JM Hashsham SA A polymer microfluidic chip for quantitative detection of multiple water- and foodborne pathogens using real-time fluorogenic loop-mediated isothermal amplification Biomedical Microdevices 2012 14 4 769 778 10.1007/s10544-012-9658-3 22566273 VanGuilder HD Vrana KE Freeman WM Twenty-five years of quantitative PCR for gene expression analysis BioTechniques 2008 44 5 619 626 10.2144/000112776 18474036 Vu NT Pardo JM Alvarez E Le HH Wyckhuys K Nguyen KL Le DT Establishment of a loop-mediated isothermal amplification (LAMP) assay for the detection of phytoplasma-associated cassava witches' broom disease Applied Biological Chemistry 2016 59 2 151 156 10.1007/s13765-015-0134-7 Wang J Wan Y Chen G Liang H Ding S Shang K Li M Dong J Du F Cui X Colorimetric detection of horse meat based on loop-mediated isothermal amplification (LAMP) Food Analytical Methods 2019 12 11 2535 2541 10.1007/s12161-019-01590-9 Wang L Fu J Zhou Y Chen G Fang C Lu Z Yu L On-chip RT-LAMP and colorimetric detection of the prostate cancer 3 biomarker with an integrated thermal and imaging box Talanta 2020 208 120407 10.1016/j.talanta.2019.120407 31816706 WHO. (2020). Food safety. Retrieved April 30, 2020, from https://www.who.int/NEWS-ROOM/FACT-SHEETS/DETAIL/FOOD-SAFETY . WHO. (2021). Hepatitis A. Retrieved July 27, 2021 from https://www.who.int/news-room/fact-sheets/detail/hepatitis-a. Wu QQ Jin W Zhou C Han SH Yang WX Zhu QY Jin QH Mu Y Integrated glass microdevice for nucleic acid purification, loop-mediated isothermal amplification, and online detection Analytical Chemistry 2011 83 9 3336 3342 10.1021/ac103129e 21456520 Wu R Meng B Corredig M Griffiths MW Efficient capturing and sensitive detection of hepatitis A virus from solid foods (green onion, strawberry, and mussel) using protamine-coated iron oxide (Fe3O4) magnetic nanoparticles and real-time RT-PCR Food Microbiology 2022 102 103921 10.1016/j.fm.2021.103921 34809947 Wu R Xing X Corredig M Meng B Griffiths MW Concentration of hepatitis A virus in milk using protamine-coated iron oxide (Fe3O4) magnetic nanoparticles Food Microbiology 2019 84 103236 10.1016/j.fm.2019.05.020 31421754 Xiong X Huang M Xu W Cao M Li Y Xiong X Tracing Atlantic Salmon (Salmo salar) in processed fish products using the novel loop-mediated isothermal amplification (LAMP) and PCR assays Food Analytical Methods 2020 13 6 1235 1245 10.1007/s12161-020-01738-y Yang B Wang X Li H Li G Cao Z Cheng X Comparison of loop-mediated isothermal amplification and real-time PCR for the diagnosis of tuberculous pleurisy Letters in Applied Microbiology 2011 53 5 525 531 10.1111/j.1472-765X.2011.03141.x 21883320 Yezli S Otter JA Minimum infective dose of the major human respiratory and enteric viruses transmitted through food and the environment Food and Environmental Virology 2011 3 1 1 30 10.1007/s12560-011-9056-7 35255645 Yi MY Ling L Neogi SB Fan YS Tang DY Yamasaki SJ Shi L Ye L Real time loop-mediated isothermal amplification using a portable fluorescence scanner for rapid and simple detection of Vibrio parahaemolyticus Food Control 2014 41 91 95 10.1016/j.foodcont.2014.01.005 Yoda T Suzuki Y Yamazaki K Sakon N Kanki M Aoyama I Tsukamoto T Evaluation and application of reverse transcription loop-mediated isothermal amplification for detection of noroviruses Journal of Medical Virology 2007 79 3 326 334 10.1002/jmv.20802 17245722 Yoneyama T Kiyohara T Shimasaki N Kobayashi G Ota Y Notomi T Totsuka A Wakita T Rapid and real-time detection of hepatitis A virus by reverse transcription loop-mediated isothermal amplification assay Journal of Virological Methods 2007 145 2 162 168 10.1016/j.jviromet.2007.05.023 17604128 Yuan D Kong J Li X Fang X Chen Q Colorimetric LAMP microfluidic chip for detecting three allergens: Peanut, sesame and soybean Scientific Reports 2018 8 1 1 8 10.1038/s41598-018-26982-5 29311619 Zahradnik C Martzy R Mach RL Krska R Farnleitner AH Brunner K Loop-mediated isothermal amplification (LAMP) for the detection of horse meat in meat and processed meat products Food Analytical Methods 2015 8 6 1576 1581 10.1007/s12161-014-0072-8 Zheng Y Hu Y Development of a fast and efficient method for hepatitis A virus concentration from green onion Journal of Virological Methods 2017 249 161 164 10.1016/j.jviromet.2017.09.013 28919035 Zhou, D. G., Guo, J. L., Xu, L. P., Gao, S. W., Lin, Q. L., Wu, Q. B., Wu, L. G., & Que, Y. X. (2014). Establishment and application of a loop-mediated isothermal amplification (LAMP) system for detection of cry1Ac transgenic sugarcane. Scientific Reports, 4.
PMC009xxxxxx/PMC9852258.txt	==== Front J Microbiol Immunol Infect J Microbiol Immunol Infect Journal of Microbiology, Immunology, and Infection 1684-1182 1995-9133 Taiwan Society of Microbiology. Published by Elsevier Taiwan LLC. S1684-1182(23)00011-7 10.1016/j.jmii.2023.01.011 Original Article Risk categorization and outcomes among healthcare workers exposed to COVID-19: A cohort study from a Thai tertiary-care center Pienthong Thanus a Chancharoenrat Watcharee b Sajak Sirinporn b Phetsaen Suphannee b Hanchai Padcharadda b Thongphubeth Kanokporn b Khawcharoenporn Thana a∗ a Division of Infectious Diseases, Department of Internal Medicine, Faculty of Medicine, Thammasat University, Pathumthani, Thailand b Infection Control Department, Thammasat University Hospital, Pathumthani, Thailand ∗ Corresponding author. Division of Infectious Diseases, Faculty of Medicine, Thammasat University, Pathumthani, 12120, Thailand. 20 1 2023 6 2023 20 1 2023 56 3 537546 30 5 2022 29 12 2022 10 1 2023 © 2023 Taiwan Society of Microbiology. Published by Elsevier Taiwan LLC. 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Background A risk categorization tool for healthcare workers (HCWs) exposed to COVID-19 is crucial for preventing COVID-19 transmission and requires validation and modification according to local context. Methods From January to December 2021, a prospective cohort study was conducted among Thai HCWs to evaluate the performance of the specifically-created risk categorization tool, which classified HCWs into low-risk (LR), intermediate-risk (IR), and high-risk (HR) groups based on types of activities, duration of exposure, and protective methods used during exposure. Subsequent measures were determined for the HCWs based on the risk categories. Results 1891 HCWs were included; 52%, 25% and 23% were LR, IR, and HR, respectively. COVID-19 was diagnosed in 1.3%, 5.1% and 27.3% of LR, IR and HR HCWs, respectively (P <0.001). Independent factors associated with COVID-19 were household or community exposure [adjusted odds ratio (aOR), 1588.68; P <0.001), being HR (aOR, 11.94; P <0.001), working at outpatient departments (aOR, 2.54; P <0.001), and no history of COVID-19 vaccination (aOR, 2.05; P = 0.01). The monthly rates of COVID-19 among LR, IR, and HR HCWs significantly decreased after the incremental rate of full vaccination. In-hospital transmission between HCWs occurred in 8% and was mainly due to eating at the same table. Conclusion The study risk categorization tool can differentiate risks of COVID-19 among the HCWs. Prevention of COVID-19 should be focused on HCWs with the identified risk factors and behaviors associated with COVID-19 development and encouraging receipt of full vaccination. Keywords Risk categorization Exposure COVID-19 Healthcare worker Thailand ==== Body pmcIntroduction Healthcare workers (HCWs) are front-line workers in the coronavirus disease 2019 (COVID-19) pandemic and are at higher risk of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) acquisition than general population. A systematic review and meta-analysis study has reported the global prevalence of COVID-19 among HCWs to be 11%,1 while the prevalence among world population has been approximately 5%.2 In Thailand, the alpha and delta variants of SARS-CoV-2 were the major causes of COVID-19 epidemics and affected more than 2 million people in 2021. The prevalence of COVID-19 among Thai HCWs was 7.75% which was higher than the prevalence of the country's general population (4.49%).2 During the epidemics, COVID-19 had significant impacts not only on HCWs' health but also their work in regards to sick leave, being isolated if they get infected, being quarantined if they have high-risk contacts and increased workload to substitute other infected or quarantined HCWs. Generally, HCWs can acquire COVID-19 from contact with SARS-CoV-2 infected individuals including household members, patients and other HCWs. Previous studies have identified risk factors for in-hospital transmission of COVID-19 among HCWs, which include prolonged periods of patient care, performing aerosol generating procedures, lack of adequate personal protective equipment (PPE) and inadequate compliance to infection prevention and control (IPC) policies.3, 4, 5 To prevent in-hospital transmission of COVID-19, the United States Centers for Disease Control and Prevention (CDC) has published the guidance for risk assessment and public health management of HCWs with potential exposure to patients with COVID-19 in a healthcare setting and recommended appropriate monitoring and work restriction for HCWs based on duration of close contact, presence of source control, and PPE use.6 The CDC's 3- level risk classification has been shown to differentiate COVID-19 risks among HCWs in the previous study.7 However, outcomes in regards to in-hospital COVID-19 transmission after implementation of the risk classification and management have not been evaluated. During the alpha and delta variant-dominant epidemics in Thailand, investigations and risk assessment have been conducted for a number of HCWs contacted with COVID-19 cases by our IPC nurses and physicians. Challenges included difficulties in categorizing HCWs to the different risk levels because the exposed HCWs reported characteristics and types of at-risk activities and behaviors different and more in detailed than those described and defined in the CDC's risk classification. Therefore, the IPC team had created a new COVID-19 risk categorization tool incorporating all relevant and detailed risk characteristics consistent with the hospital local context. This study aimed at evaluating the performance of the specifically-created risk categorization tool, determining factors associated with SARS-CoV-2 acquisition and assessing related outcomes and in-hospital transmission among HCWs. Methods Study design and setting A prospective cohort study was conducted among all HCWs who exposed to persons with confirmed COVID-19 during the period from January 1st to December 31st, 2021, at Thammasat University Hospital in Pathumthani, Thailand. The hospital is a 734-bed tertiary-care medical center in central Thailand and employed a total of 5996 HCWs in 2021. This study was approved by the Human Research Ethics Committee of Thammasat University (Medicine). Consent was obtained from all participating HCWs. Study protocol According to our hospital IPC protocols during the COVID-19 epidemic, HCWs were required to report all of their COVID-19 exposures to the IPC department regardless of whether they had or did not have symptoms consistent with COVID-19. The exposures were subsequently investigated by trained infection control nurses and infectious disease specialists to categorize the HCWs into three-level risk groups; low-risk exposure (LR), intermediate-risk exposure (IR), and high-risk exposure (HR) based on the study risk categorization tool. The tool was created by the IPC team and modified from the CDC recommendations.6 Additional risk characteristics and behaviors had been added to the tool as they were described in details by the HCWs during the investigations (Supplementary Table 1 and Supplementary Fig. 1). A HCW with any exposure characteristics with the high risk level will be regarded as being in the high-risk group. In case a HCW had exposure characteristics with more than one risk levels, he or she will be categorized to the highest risk level. All HCWs exposed to COVID-19 were required to follow the hospital IPC measures for monitoring and follow-up (Supplementary Fig. 2). These measures indicate the need for serial SARS-CoV-2 real-time polymerase chain reaction (RT-PCR) testing, quarantine, appropriate mask wearing, maintaining physical distancing (≥2 m) while dining and when attending hospital activities, and performing hand hygiene according to the World Health Organization's 5 moments.8 In addition, use of an N95 respirator, face shield/googles, gloves and gown were required when performing aerosol generating procedures. All of the HCWs with COVID-19 exposure were followed-up for COVID-19 development during the 14-day observation period, clinical characteristics and outcomes of COVID-19, and subsequent in-hospital transmission. Data collection and outcome measurement The collected data included demographics, comorbidities, occupation, source of risk exposure, type of exposure, the use of PPE during exposure, COVID-19 vaccination history, subsequent RT-PCR test results, symptoms and clinical outcomes of COVID-19. The severity of COVID-19 was classified based on the World Health Organization's criteria.9 The primary outcome was the difference in rates of COVID-19 development in the LR, IR and HR HCWs. The secondary outcomes included the factors associated with COVID-19 among HCWs, the rate of and factors associated with in-hospital COVID-19 transmission, and clinical manifestations and outcomes among HCWs. Statistical analysis All analyses were performed using IBM SSPS Statistics version 26 software (IBM Corp., Armonk, NY, USA). Descriptive data were described in numbers, percentages and a median with interquartile range (IQR). Categorical data were compared using a chi-square test or Fisher's exact test as appropriate while continuous data were compared using Mann Whiney U test. All P values were 2- tailed, and P <0.05 was considered statistically significant. Variables that were significantly associated with COVID-19 development at a significance level of P less than 0.20 in univariable analyses or had been previously reported to be significant factors were entered into backward stepwise logistic regression models. Adjusted odd ratios (aORs) and 95% confidence interval (CI) were calculated in multivariable logistic regression analysis to determine factors associated with COVID-19 development among the HCWs. Results Characteristics of the study HCWs (Table 1) During the study period, there were 1891 HCWs exposed to persons with confirmed COVID-19. Of these HCWs, 984 (52%), 467 (25%) and 440 (23%) were categorized into LR, IR, and HR groups, respectively. The median age of HCWs was 30 years (IQR, 26–36 years), female sex predominated (1485/1891; 79%), and the median body mass index was 22.8 kg/m2 (IQR, 20.3–25.8 kg/m2). Most of HCWs had no comorbidities (1455/1891; 77%), while 6% (107/1891) had hypertension, and 4% (78/1891) had diabetes mellitus. The majority of HCWs were nurses (625/1891; 33%), assistant nurses (438/1891; 23%), and physicians (347/1891; 18%) and worked in non-COVID-19 inpatient departments (912/1891; 48%). The most common source of risk exposure were HCWs (59%), and the three most common risk activities were being in the same room with closed space without wearing a mask (75%), sleeping in the same on-duty rooms without wearing a mask (29%) and poor adherence to hand hygiene (24%). Comparing between HR and LR HCWs, HR HCWs were younger (29 vs. 30 years) and had a higher proportion of HCWs who were physician (21% vs. 16%), worked in non-COVID-19 inpatient departments (50% vs. 42%) or outpatient departments (15% vs. 9%) and exposed COVID-19 in household (7% vs. 0%) or community sources (9% vs. 0%).Table 1 Characteristics and SAR-CoV-2 positivity rate of healthcare workers (HCWs) who exposed to persons with confirmed coronavirus diseases 2019 (COVID-19) stratified by risk category. Table 1 Characteristics Total (n = 1891) Risk categorizationa P valueb LR (n = 984) IR (n = 467) HR (n = 440) Age, years, median (IQR) 30 (26–36) 30 (26–37) 29 (26–34) 29 (26–35) 0.003 Female, 1485 (78.5) 762 (77.4) 367 (78.6) 356 (80.9) 0.337 Comorbidities Previously healthy 1455 (76.9) 776 (78.9) 335 (71.7) 344 (78.2) 0.008 Diabetes Mellitus 78 (4.1) 35 (3.6) 26 (5.6) 17 (3.9) 0.189 Hypertension 107 (5.7) 41 (4.2) 40 (8.6) 26 (5.9) 0.003 Dyslipidemia 73 (3.9) 36 (3.7) 23 (4.9) 14 (3.2) 0.353 Pulmonary disease 29 (1.5) 9 (0.9) 10 (2.1) 10 (2.3) 0.073 Othersc 267 (14.1) 142 (14.4) 74 (15.8) 51 (11.6) 0.170 Body Mass Index, kg/m2, median (IQR) 22.8 (20.3–25.8) 22.7 (20.4–26.0) 22.4 (20.0–25.4) 23.1 (20.3–25.6) 0.425 Occupation <0.001 Physician 347 (18.4) 154 (15.7) 100 (21.4) 93 (21.1) Nurse 625 (33.1) 352 (35.8) 160 (34.3) 113 (25.7) Assistant nurse 438 (23.2) 223 (22.7) 102 (21.8) 113 (25.7) Pharmacist or assistant pharmacist 56 (3) 39 (4) 5 (1.1) 12 (2.7) Laboratory technician 14 (0.7) 1 (0.1) 1 (0.2) 12(2.7) Medical or nursing student 78 (4.1) 45 (4.6) 21 (4.5) 12 (2.7) Other HCWs with patient contactd 126 (6.7) 53 (5.4) 37 (7.9) 36 (8.2) Other HCWs without patient contacte 206 (10.9) 117 (11.9) 41 (8.8) 48 (10.9) Working place <0.001 COVID-19 inpatient department 57 (3) 18 (1.8) 8 (1.7) 31 (7) Non COVID-19 inpatient department 912 (48.2) 416 (42.3) 275 (58.9) 221 (50.2) Outpatient department 210 (11.1) 90 (9.1) 53 (11.3) 67 (15.2) Emergency department 217 (11.5) 180 (18.3) 26 (5.6) 11 (2.5) Laboratory department 14 (0.7) 1 (0.1) 1 (0.2) 12(2.7) Radiology department 63 (3.3) 28 (2.8) 27 (5.8) 8 (1.8) Operation room 135 (7.1) 74 (7.5) 22 (4.7) 39 (8.9) Othersf 283 (15) 178 (18) 56 (12) 49 (11.1) Source of risk exposureg <0.001 Patient 697(36.9) 346 (35.2) 229 (49) 122 (27.7) Healthcare worker 1119 (59.2) 638 (64.8) 232 (49.7) 249 (56.6) Household 35 (1.9) 0 (0) 4 (0.9) 31 (7) Community 40 (2.1) 0 (0) 2 (0.4) 38 (8.6) Risk exposure activities Eating at the same non-partitioned table 140 (7.4) 15 (1.5) 9 (1.9) 116 (26.4) <0.001 Eating at the same partitioned table 135 (7.1) 9 (0.9) 21 (4.5) 105 (23.9) <0.001 Sleeping in the same room (both did not wear a mask) 55 (29) 0 (0) 1 (0.1) 54 (12.3) <0.001 Being in the same room (both did not wear a mask) Closed space (≤15 m2) 658 (34.8) 130 (13.2) 264 (56.5) 264 (60) <0.001 Closed space (>15 m2) 768 (40.6) 575 (58.4) 131 (28.1) 62 (14.1) <0.001 Open space 395 (20.9) 276 (28) 69 (14.8) 50 (11.4) <0.001 Face-to-face contact within distance of <2 m (wearing mask) 1667 (88.2) 962 (97.8) 334 (71.5) 371 (84.3) <0.001 Poor adherence to hand washing 459 (24.3) 180 (18.3) 161 (34.5) 118 (26.8) <0.001 Performing aerosol generating procedures without wearing N95 mask 103 (5.4) 10 (1) 20 (4.3) 73 (16.6) <0.001 Duration of risk exposure activities, minutes, median (IQR) 5 (5–10) 5 (3–5) 10 (10–10) 15 (15–30) <0.001 Protective method during exposure to COVID-19 N95 mask with a covering surgical mask 70 (3.7) 67 (6.8) 0 (0) 3 (0.7) <0.001 N95 mask only 64 (3.4) 45 (4.6) 19 (4.1) 0 (0) <0.001 Surgical mask with a covering cloth mask 974 (51.5) 552 (56.1) 310 (66.4) 112 (25.5) <0.001 Surgical mask only 343 (18.1) 296 (30.1) 41 (8.8) 6 (1.4) <0.001 Face shield or goggles with a mask or two masks 576 (30.5) 523 (53.2) 50 (10.7) 3 (0.7) <0.001 Gloves 422 (22.3) 229 (23.3) 120 (25.7) 73 (16.6) 0.003 Gown 177 (9.4) 93 (9.5) 80 (17.1) 4 (0.9) <0.001 Medical hair cover 52 (2.7) 32 (3.3) 20 (4.3) 0 (0) <0.001 RT-PCR for SAR-CoV-2 positivity 157 (8.3) 13 (1.3) 24 (5.1) 120 (27.3) <0.001 NOTE. IQR = interquartile range; RT-PCR = real-time polymerase chain reaction; SARS-CoV-2 = severe acute respiratory syndrome coronavirus-2. Data are in numbers (%), unless indicated otherwise. a Based on Thammasat University Hospital Infection Prevention and Control protocol for risk assessment and measures for HCWs with risk exposure to SARS-CoV-2. b Comparison between HCWs who had low, intermediate, and high-risk exposure to persons with confirmed COVID-19. c Included thyroid diseases, allergic rhinitis, chronic hepatitis B, gastroesophageal reflux disease, benign prostatic hyperplasia, obstructive sleep apnea, and systemic lupus erythematosus. d Included physical therapists, radiologic technicians, maids, and patient transporters. e Include clerks, security guards, and gardeners. f Included nursing department, physical therapy department, planning and finance department, medical supplies department. g Household acquired COVID-19 is defined as symptoms' onset or positive SAR-CoV-2 RT-PCR within 14 days after last contact with persons in the same household with COVID-19. Community acquired COVID-19 is defined as symptoms' onset or positive SAR-CoV-2 RT-PCR within 2 days after admission (or within 7 days with a strong suspicion of community transmission). COVID-19 development among the study HCWs During the 14-day observation period, 157 HCWs (8%) developed COVID-19. The rates of COVID-19 development were significantly different between each risk group (P < 0.001). The highest rate was in HR group (27.3%), followed by IR group (5.1%) and LR group (1.3%). Comparing characteristics between the HCWs with and without subsequent COVID-19 development (Table 2 ), those with COVID-19 were more-likely to be male (19% vs. 14%) and assistant nurse (30% vs. 23%), worked at outpatient departments (24% vs. 10%), had household exposure (22% vs. 0%) and community exposure (26% vs. 0%), and had no history of COVID-19 vaccination (15% vs. 4%). By multivariable logistic regression analysis, factors associated with COVID-19 among the HCWs included household or community exposure (aOR, 1588.68; P <0.001), being HR (aOR, 11.94; P <0.001), working at outpatient departments (aOR, 2.54; P <0.001), and no history of COVID-19 vaccination (aOR, 2.05; P = 0.01) (Table 3 ). The aORs of low-, intermediate-, and high-risk groups for development of COVID-19 after adjusting for community/household exposure were 0.15 (95% CI 0.08–0.27; P < 0.001), 0.83 (95% CI 0.49–1.40; P = 0.45), and 7.12 (95% CI 4.50–11.27; P < 0.001), respectively. Among the high-risk HCWs, the rates of COVID-19 development among those who worked in COVID-19 inpatients departments (19.3%) and outpatient departments (13.8%) were significantly higher than the rates among those working in non-COVID-19 inpatient department (3.6%) and the emergency department (4.1%). The rates of COVID-19 development were also significantly higher among HCWs working in COVID-19 inpatients departments than those working in non-COVID-19 inpatient department for intermediate-risk groups (5.3% vs. 0.9%; P = 0.02) and high-risk groups (19.2% vs. 3.6%; P < 0.001), while the rates were comparable for low-risk groups (0% vs. 1.1%).Table 2 Comparison of characteristics between exposing healthcare workers (HCWs) with and without subsequent coronavirus disease 2019 (COVID-19) development. Table 2Characteristics COVID-19 (n = 157) No COVID-19 (n = 1734) P valuea Age, years, median (IQR) 31 (26–40) 29 (26–36) 0.133 Female 135 (86) 1350 (90.9) 0.017 Occupation <0.001 Physician 16 (10.2) 331 (19.1) Nurse 34 (21.7) 592 (34.1) Assistant nurse 47 (29.9) 391 (22.5) Pharmacist or assistant pharmacist 3 (1.9) 53 (3.1) Laboratory technician 4 (2.5) 10 (0.6) Medical or nursing practitioner 0 (0) 78 (4.5) Other HCWs with patient contactb 25 (15.9) 101 (5.8) Other HCWs without patient contactc 28 (17.8) 178 (10.3) Working place <0.001 COVID-19 inpatient department 14 (8.9) 43 (2.5) Non COIVD-19 inpatient department 51 (32.5) 861 (49.7) Outpatient department 37 (23.6) 173 (10) Emergency department 10 (6.4) 207 (11.9) Laboratory department 4 (2.5) 10 (0.6) Radiology department 4 (2.5) 59 (3.4) Operation room 12 (7.6) 123 (7.1) Othersd 25 (15.9) 258 (14.9) Source of risk exposuree <0.001 Patient 70 (44.6) 627 (36.2) Healthcare worker 12 (7.6) 1107 (63.8) Household 35 (22.3) 0 (0) Community 40 (25.5) 0 (0) History of COVID-19 vaccination <0.001 None 23 (14.6) 70 (4) At least one dose 15 (9.6) 82 (4.7) Two doses 101 (64.3) 1184 (68.3) Three doses 18 (11.5) 398 (23) One dose of vaccination CoronaVac 9 (5.7) 24 (1.4) <0.001 ChAdOx1 6 (3.8) 58 (3.3) 0.752 Two doses of vaccination CoronaVac + CoronaVac 92 (58.6) 1091 (62.9) 0.284 ChAdOx1 + ChAdOx1 9 (5.7) 89 (5.1) 0.745 CoronaVac + ChAdOx1 0 (0) 2 (0.1) 0.670 CoronaVac + BNT162b2 0 (0) 1 (0.1) 0.763 ChAdOx1 + BNT162b2 0 (0) 1 (0.1) 0.763 Three doses of vaccination CoronaVac + CoronaVac + ChAdOx1 15 (9.6) 288 (16.6) 0.021 CoronaVac + CoronaVac + BNT162b2 3 (1.9) 110 (6.3) 0.025 Duration from the last dose of COVID vaccine and the time of risk exposure, days, median (IQR) 63 (35–90) 63 (26–36) 0.363 Duration of risk exposure activities, minutes, median (IQR) 15 (10–20) 5 (5–10) <0.001 Risk categorization <0.001 Low risk 13 (8.3) 971 (56) Intermediate risk 24 (15.3) 443 (25.5) High risk 120 (76.4) 320 (18.5) NOTE. Data are in numbers (%), unless indicated otherwise. a Comparison between at-risk HCWs with and without subsequent COVID-19 development. b Included physical therapists, radiologic technicians, maids, and patient transporters. c Include clerks, security guards, and gardeners. d Included nursing department, physical therapy department, planning and finance department, medical supplies department. e Household acquired COVID-19 is defined as symptoms' onset or positive SAR-CoV-2 RT-PCR within 14 days after last contact with persons in the same household with COVID-19. Community acquired COVID-19 is defined as symptoms' onset or positive SAR-CoV-2 RT-PCR within 2 days after admission (or within 7 days with a strong suspicion of community transmission). Table 3 Multivariable logistic regression analysis for factors associated with coronavirus disease 2019 (COVID-19) development in the healthcare workers (HCWs). Table 3Factors Adjusted OR (95% CI) P value Household or community exposure 1588.68 (218.24–11564.84) <0.001 High risk exposure 11.94 (7.69–18.53) <0.001 Working at outpatient departments 2.54 (1.61–4.00) <0.001 No history of COVID-19 vaccination 2.05 (1.17–3.61) 0.012 Assistant nurse 1.23 (0.82–1.85) 0.325 Duration of exposure 1.00 (0.99–1.03) 0.394 Male sex 0.60 (0.36–1.00) 0.053 NOTE: CI = confidence interval; OR = odds ratio. Of the 157 HCWs who developed COVID-19, 19 (12%) were asymptomatic, 126 (80%) had mild disease, and 12 (8%) had moderate disease. Among those with symptomatic COVID-19, common symptoms were fever (81%), cough (69%), sore throat (51%) and nasal congestion or rhinorrhea (44%). The median cycle threshold for RT-PCR test was significantly lower in symptomatic compared to asymptomatic HCWs with COVID-19 (18.8 vs. 22.6; P = 0.007). All of the HCWs with COVID-19 completely recovered by day 14 after the diagnosis. When analyzing the monthly data, the rate of COVID-19 among LR, IR, and HR HCWs significantly decreased after the incremental rate of full vaccination (at least 2 doses of viral vector or mRNA COVID-19 vaccines or 2 doses of inactivated vaccine with one booster dose of viral vector or mRNA vaccine) among the HCWs (Fig. 1 ). There were no cases of COVID-19 in any risk groups in the last trimester of 2021 as the rate of full vaccination went up to 27.17%.Figure 1 Monthly rates of full vaccination and COVID-19 development among healthcare workers (HCWs) with high-risk (HR), intermediate-risk (IR) and low-risk (LR) exposure. NOTE: Full vaccination was defined as HCW who received at least 2 doses of viral vector or mRNA COVID-19 vaccines or 2 doses of inactivated vaccine with one booster dose of viral vector or mRNA vaccine. Fig. 1 In-hospital COVID-19 transmission Among the 157 HCWs with COVID-19, 12 (8%) developed COVID-19 after in-hospital HCW to HCW transmission. The transmission between HCWs mainly occurred when the HCWs ate together at the same tables (7/12; 58%) (Table 4 ). Mostly, each one of the index HCWs transmitted SARS-CoV-2 to only one of these 12 HCWs. However, there was one index HCW transmitted the virus to the other 2 HCWs of the 12 HCWs as he had worked in three different areas including an operating room, an intensive care unit, and an outpatient department.Table 4 Summary of the 12 healthcare workers (HCWs) who developed coronavirus disease 2019 (COVID-19) due to in-hospital transmission. Table 4No. Age Sex Occupation Characteristics of risk exposure with another HCW with COVID-19 Duration of exposure (minute) Location of exposure PPE wearing Risk level Vaccination history Severity of disease 1 37 Male Physician Eating at the same non-partitioned table 30 Common room None HR CoronaVac, CoronaVac Mild 2 37 Female Assistant Nurse Eating at the same non-partitioned table 30 Dining room None HR CoronaVac, CoronaVac Mild 3 42 Female Assistant Nurse Eating at the same non-partitioned table 30 Dining room None HR CoronaVac, CoronaVac Mild 4 24 Female Assistant Nurse Face-to-face contact within distance of <2 m 15 Ward Surgical mask IR CoronaVac, CoronaVac Mild 5 29 Female Assistant Nurse Being in the same room Closed space ≤15 m2 30 Ward Surgical mask HR CoronaVac, CoronaVac Mild 6 42 Female Assistant Pharmacist Eating at the same non-partitioned table 30 Dining room None HR CoronaVac, CoronaVac Mild 7 28 Female Assistant Nurse Face-to-face contact within distance of <2 m 60 Ward Double mask IR None Mild 8 27 Female Nurse Eating at the same non-partitioned table 30 Dining room None HR CoronaVac, CoronaVac Mild 9 43 Female Laboratory technician Being in the same room Closed space ≤15 m2 60 Laboratory Surgical mask HR None Mild 10 34 Female Assistant Nurse Eating at the same non-partitioned table 30 Dining room None HR CoronaVac, CoronaVac Mild 11 22 Female Nurse Eating at the same non-partitioned table 30 Dining room None HR ChAdOx1 None 12 32 Female Assistant Nurse Being in the same room Closed space ≤15 m2 30 Ward Surgical mask IR CoronaVac, CoronaVac None Discussion This study evaluates the performance of a specifically-created risk categorization tool for HCWs exposed to COVID-19 during the alpha and delta variant-dominant epidemics in Thailand. The main findings suggest that the study risk categorization tool can differentiate risks of COVID-19 among the HCWs with a clear dose–response relationship between exposure intensity and infection rates. These findings are consistent with those reported from a previous study which evaluated the performance of the Centers for Disease Control and Prevention (CDC)'s 3-level risk classification in the real-world setting.7 However, in our risk categorization tool, several detailed risk characteristics and activities had been added to the tool to better categorize the risks and provide appropriate measures for the HCWs base on their risk levels. The modification included adding detailed risk characteristics, such as duration of exposure to, space of a room staying together with, distance and duration of taking with, use of partition when having food with, and use of double masking when contacting persons with COVID-19 to the tool. Among the high-risk group, the risk of developing COVID-19 is higher for high-risk HCWs working in COVID-19 inpatient departments and outpatient departments than those working in other departments. These indicate that the application of our risk categorization tool should be especially considered in these high-risk departments. We have identified a number of factors associated with COVID-19 among the exposing HCWs. These included household or community exposure, being categorized in the HR group, working at outpatient departments, and no history of COVID-19 vaccination. The rate of household transmission among our HCWs was 22.3% in this study which was higher than the rate reported in a Turkish study of 5.9%.10 This finding was likely due to the fact that most of Thai families are large (average of 3.5 people per household)11 which increases the risk of SARS-CoV-2 transmission12 and once one of the family members is infected, it is difficult for him or her to self-isolate at home. Household or community was the more common source of COVID-19 exposure than a healthcare setting for our HCWs, consistent with reports from other studies.13, 14, 15 This was likely due to the more compliance to infection control measures for COVID-19 while the HCWs worked in healthcare settings than when they were at home or a community. Working at outpatient departments was at increased risk for acquiring SARS-CoV-2 than working in other departments in our study. This may be due to the higher number of patients whom the HCWs had to encounter and the difficulties to have all of these patients compliant with the hospital COVID-19 preventive measures in outpatient settings. Lastly, the HCWs who did not receive COVID-19 vaccination were at higher risk for COVID-19 development after exposure. This finding was consistent with those reported form other studies16 and confirmed the effectiveness of COVID-19 vaccines.17 In addition, our study also demonstrates that the rate of COVID-19 significantly decreased to 0% among LR, IR, and HR HCWs in the last trimester of 2021. This may be due to the fact that the rate of complete vaccination had increased among our HCWs during that period as well as the decrease in overall incidence of COVID-19 in the general Thai population. Our study reveals that HCWs who developed COVID-19 received 3-dose COVID-19 regimens (2 doses of CoronaVac + one dose of either ChAdOx1 or BNT162b2) in a significantly less proportion compared to those who did not develop COVID-19. These might indicate the requirement of at least 3 doses of vaccines (2 inactivated + 1 booster dose of viral vector or mRNA vaccine) to be effective in preventing COVID-19 as demonstrated in another study.18 Altogether, these results suggest that prevention of COVID-19 among HCWs should focus on reducing risk behaviors, improving infection control compliance in household or community settings,19, 20 and while working at the high-risk areas such as outpatient departments. In addition, all HCWs are required to receive complete COVID-19 vaccination with at least one booster dose of viral vector or mRNA vaccine. Given the additional independent risk factors associated with COVID-19 identified in this study, further studies are needed to incorporate these factors into our original risk categorization tool and evaluate the performance of the revised tool in predicting COVID-19 and managing HCWs according to the risk level. In this study, the rate of in-hospital HCW-to-HCW transmission was 7.6% which was lower than the reported rate from a systematic review and meta-analysis (51.7%).21 The difference in the rates of transmission may be due to better compliance with the IPC measures after COVID-19 exposure of our HCWs than the other study's HCWs. We believe that the proposed infection control measures (shown in Supplementary Fig. 2) which include frequency of follow-up RT-PCR testing, duration of quarantine and duration of symptom observation for the different risk categories are appropriate since these measures were implemented based on the incubation period and natural history of COVID-19 caused by the current variants of SARS-CoV-2 at that time and were according to the national and international guidelines.6 The activities mostly reported to be associated with the transmission in our study were eating at the same table and prolonged period of exposure in poorly ventilated rooms. These findings were similar to those reported in the previous study22 and suggest that HCWs should have their meals at the different times, or keep distance for at least 2 m or use partitions if they need to have meals together, and avoid staying in the same room with poor ventilation (<1 L/s per person) for long period of time,23 especially if a mask cannot be worn. There are some recognizable limitations in this study. First, we used self-report and interviews to collect information in regards to at-risk activities and behaviors of the HCWs, which might lead to recall bias. However, the investigations that were conducted by a trained and experienced IPC team and used appropriate contact tracing questions and data collection technique should minimize this bias. Second, this was a single center study. The findings may not be generalizable to other settings with differences in infection control measures and associated resources. Lastly, we did not assess SARS-CoV-2 variants, antibody levels against SARS-CoV-2 and other immunological responses after COVID-19 vaccination, which might impact the transmission and infection rates among the HCWs. In conclusion, the study risk categorization tool, after modified according to the local context, has a good performance in differentiating risks of COVID-19 among the HCWs. The HCWs who are categorized as HR, expose COVID-19 in household or community settings, work in outpatient departments, and have not received or received incomplete vaccination should be monitored for compliance to infection control measures as they are at higher risk for COVID-19 development. The in-hospital HCW-to-HCW transmission can be prevented by avoidance of having meals at the same table and staying in the same room with poor ventilation for long period of time without wearing masks, in additional to the standard infection control measures. Funding None declared. Declaration of competing interest None declared. Appendix A Supplementary data The following are the Supplementary data to this article.Multimedia component 1 Multimedia component 1 Multimedia component 2 Multimedia component 2 figs1 figs2 Acknowledgement We thank the personnel of Screening & Admissions unit, Infectious Control unit and Laboratory Department of Thammasat University Hospital for their contribution in data of this study. Appendix A Supplementary data to this article can be found online at https://doi.org/10.1016/j.jmii.2023.01.011. ==== Refs References 1 Dzinamarira T. Murewanhema G. Mhango M. Iradukunda P.G. Chitungo I. Mashora M. COVID-19 prevalence among healthcare workers. A systematic review and meta-analysis Int J Environ Res Public Health 19 1 2021 146 35010412 2 Worldometer. Report coronavirus cases 2022 Available at: https://www.worldometers.info/coronavirus/ 3 Kishk R.M. Nemr N. Aly H.M. Soliman N.H. Hagras A.M. Ahmed A.A. Assessment of potential risk factors for coronavirus disease-19 (COVID-19) among health care workers J Infect Public Health 14 10 2021 1313 1319 34281792 4 Jain U. Risk of COVID-19 due to Shortage of personal protective equipment Cureus 12 6 2020 8837 5 Tran K. Cimon K. Severn M. Pessoa-Silva C.L. Conly J. Aerosol generating procedures and risk of transmission of acute respiratory infections to healthcare workers: a systematic review PLoS One 7 4 2012 e35797 6 Centers for Disease Control and Prevention Interim guidance for managing healthcare personnel with SARS-CoV-2 infection or exposure to SARS-CoV-2 2022 Accessed January 01, 2021 https://www.cdc.gov/coronavirus/2019-ncov/hcp/guidance-risk-assesment-hcp.html 7 Gragnani C.M. Fernandes P. Waxman D.A. Validation of Centers for Disease Control and Prevention level 3 risk classification for healthcare workers exposed to severe acute respiratory coronavirus virus 2 (SARS-CoV-2) Infect Control Hosp Epidemiol 42 4 2021 483 485 33280637 8 World Health Organization Clean your hands in the context of COVID-19 2020 Accessed April 05, 2020 https://www.who.int/publications/m/item/save-lives-clean-your-hands-in-the-context-of-covid-19 9 World Health Organization Living guidance for clinical management of COVID-19 2021 Accessed January 01, 2021 10 Çelebi G. Pişkin N. Bekleviç A.Ç. Altunay Y. Keleş A.S. Tüz M.A. Specific risk factors for SARS-CoV-2 transmission among health care workers in a university hospital Am J Infect Control 48 10 2020 1225 1230 32771498 11 Global Data Lab area database 4.0. Average household size in Thailand 2020 Accessed January 01, 2021 https://globaldatalab.org/areadata/hhsize/THA/ 12 Gillies C.L. Rowlands A.V. Razieh C. Nafilyan V. Chudasama Y. Islam N. Association between household size and COVID-19: a UK Biobank observational study J R Soc Med 115 4 2022 138 144 35118908 13 Al Maskari Z. Al Blushi A. Khamis F. Al Tai A. Al Salmi I. Al Harthi H. Characteristics of healthcare workers infected with COVID-19: a cross-sectional observational study Int J Infect Dis 102 2021 32 36 33039607 14 World Health Organization Report of the WHO–China Joint Mission on coronavirus disease 2019 (COVID-19) Feb 28, 2020 Available at: https://www.who.int/publications/i/item/report-of-the-who-china-joint-mission-oncoronavirus-disease-2019-(covid-19) 15 Schwartz K.L. Achonu C. Buchan S.A. Brown K.A. Lee B. Whelan M. Epidemiology, clinical characteristics, household transmission, and lethality of severe acute respiratory syndrome coronavirus-2 infection among healthcare workers in Ontario, Canada PLoS One 15 12 2020 e0244477 16 Naleway A.L. Grant L. Caban-Martinez A.J. Wesley M.G. Burgess J.L. Groover K. Incidence of SARS-CoV-2 infection among COVID-19 vaccinated and unvaccinated healthcare personnel, first responders, and other essential and frontline workers: Eight US locations, January–September 2021 Influenza Other Respi Viruses 16 2022 585 593 17 Bedston S. Akbari A. Jarvis C.I. Lowthian E. Torabi F. North L. COVID-19 vaccine uptake, effectiveness, and waning in 82,959 health care workers: a national prospective cohort study in Wales Vaccine 40 2022 1180 1189 35042645 18 Sritipsukho P. Khawcharoenporn T. Siribumrungwong B. Damronglerd P. Suwantarat N. Satdhabudha A. Comparing real-life effectiveness of various COVID-19 vaccine regimens during the delta variant-dominant pandemic: a test-negative case-control study Emerg Microbes Infect 11 1 2022 Dec 585 592 35114893 19 Denford S. Morton K. Horwood J. de Garang R. Yardley L. Preventing within household transmission of Covid-19: is the provision of accommodation to support self-isolation feasible and acceptable BMC Publ Health 21 1 2021 1 13 20 Wang Y. Tian H. Zhang L. Zhang M. Guo D. Wu W. Reduction of secondary transmission of SARS-CoV-2 in households by face mask use, disinfection and social distancing: a cohort study in Beijing, China BMJ Glob Health 5 5 2020 e002794 21 Gholami M. Fawad I. Shadan S. Rowaiee R. Ghanem H. Khamis A.H. COVID-19 and healthcare workers: a systematic review and meta-analysis Int J Infect Dis 104 2021 335 346 33444754 22 Gordon C.L. Trubiano J.A. Holmes N.E. Chua K.Y. Feldman J. Young G. Staff to staff transmission as a driver of healthcare worker infections with COVID-19 Infect Dis Health 26 4 2021 276 283 34344634 23 Li Y. Qian H. Hang J. Chen X. Cheng P. Ling H. Probable airborne transmission of SARS-CoV-2 in a poorly ventilated restaurant Build Environ 196 2021 1077 1088
PMC009xxxxxx/PMC9862229.txt	==== Front Food Environ Virol Food Environ Virol Food and Environmental Virology 1867-0334 1867-0342 Springer US New York 36680664 9549 10.1007/s12560-023-09549-0 Research Surface Inactivation of a SARS-CoV-2 Surrogate with Hypochlorous Acid is Impacted by Surface Type, Contact Time, Inoculum Matrix, and Concentration Hamilton Allyson N. 1 Chandran Sahaana 1 Baker Christopher A. 12 Gibson Kristen E. [email protected] 1 1 grid.411017.2 0000 0001 2151 0999 Department of Food Science, Center for Food Safety, University of Arkansas System Division of Agriculture, 1371 West Altheimer Dr., Fayetteville, AR 72704 USA 2 grid.483501.b 0000 0001 2106 4511 Present Address: U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, 5001 Campus Drive, College Park, MD 20740 USA 21 1 2023 2023 15 2 116122 2 12 2022 13 1 2023 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Indirect contact with contaminated surfaces is a potential transmission route for COVID-19. Therefore, it is necessary to investigate convenient and inexpensive surface sanitization methods, such as HOCl, against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 surrogate, Phi6 (~ 7 log PFU/mL), was prepared in artificial saliva and tripartite matrices, spot inoculated on coupons of either stainless steel or vinyl, and allowed to dry. The coupons were sprayed with either 500 ppm or 1000 ppm HOCl, and remained on the surface for 0 s (control), 5 s, 30 s, or 60 s. Samples were enumerated via the double agar overlay assay. Statistical analysis was completed in R using a generalized linear model with Quasipoisson error approximations. Time, concentration, surface type, and inoculum matrix were all significant contributors to log reduction at P = 0.05. Significant three-way interactions were observed for 1000 ppm, vinyl, and 60 s (P = 0.03) and 1000 ppm, tripartite, and 60 s (P = 0.0121). A significant two-way interaction between vinyl and 60 s was also observed (P = 0.0168). Overall, increased HOCl concentration and exposure time led to increased Phi6 reduction. Notably, the highest estimated mean log reduction was 3.31 (95% CI 3.14, 3.49) for stainless steel at 60 s and 1000 ppm HOCl in artificial saliva, indicating that this method of sanitization may not adequately reduce enveloped viruses to below infective thresholds. Keywords Fomite Phi6 Hypochlorous acid Vinyl Stainless steel http://dx.doi.org/10.13039/100005825 National Institute of Food and Agriculture 2020-67017-32427 2020-67017-32427 Baker Christopher A. Gibson Kristen E. issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic continues to cause illness and death throughout the world, with nearly 6.5 billion illnesses and more than 6.6 million deaths attributed thus far (Schiffman & Conlon, 2019). Patel and others note that there are six known ways in which SARS-CoV-2 can be spread (respiratory/droplet, indirect, fecal–oral, vertical, sexual, and ocular) (Patel et al., 2020). Even with widespread illness and death, one-in-five U.S. adults are unwilling to be vaccinated against SARS-CoV-2 (Allen et al., 2021). Therefore, additional preventative measures must be implemented in order to reduce the transmission of SARS-CoV-2 and subsequent burden on healthcare systems. Since BSL-3 environments are needed to work with live samples of SARS-CoV-2, surrogates have been widely employed. Phi6 is a member of the Cystoviridae family and is among the few bacteriophages to have a lipid envelope (Vidaver et al., 1973). The bacteriophage has a double-stranded 13.4 kbp RNA genome and is similar in size to SARS-CoV-2 at approximately 75 nm in diameter (Fedorenko et al., 2020; Frilander et al., 1995; Gonzalez et al., 1977). Phi6 has been investigated as a surrogate for both Ebola viruses and SARS-CoV-2 (Baker et al., 2022a; Bangiyev et al., 2021, Fedorenko et al., 2020; Gallandat et al., 2017; Whitworth et al., 2020; Wood et al., 2020;). The persistence and transfer of Phi6 on fomites has also been widely explored (Anderson & Boehm, 2021; Baker et al., 2022a, 2022b; Bangiyev et al., 2021; Fedorenko et al., 2020; Gallandat et al., 2017; Whitworth et al., 2020; Wood et al., 2020). The host of Phi6 is Pseudomonas syringae pathovar phaseolicola (Pph), making both Phi6 and its host BSL-1 microorganisms simple to cultivate and use as a surrogate for highly pathogenic enveloped viruses (Aquino de Carvalho et al, 2017). Hypochlorous acid (HOCl) is naturally produced by immune cells in mammals in response to injury or infection (Kettle & Winterboum, 1997), and is capable of viral inactivation by forming chloramines and nitrogen-centered radicals. These reactive compounds result in strand breaks of genetic material and destruction of the nucleic acids that form the virus (Block & Rowan, 2020; Winter et al., 2008). In situ production of HOCl can also be achieved by combining non-iodinated salt, water, acetic acid (e.g., vinegar), and electrolysis (Block & Rowan, 2020; Chlorking, 2021). More specifically, non-iodinated salt is mixed with water to produce a salt solution followed by the addition of vinegar (Farah & Al-Haj Ali, 2021). This solution is then subjected to electrolysis for production of HOCl, or electrolyzed water which can be acidic or neutral depending on the process. The hypochlorite ion (OCl−) has been tested against different viruses including three strains of murine hepatitis virus, canine coronavirus, human norovirus, murine norovirus, and MS2 bacteriophage (Dellano et al., 2009; Park et al., 2007; Saknimit et al, 1988). The typical use of sodium hypochlorite is 500 ppm, but the summarized data by Kampf et al. (2020) suggest exposure to 1000 ppm for 1 min is required for complete inactivation of SARS-CoV-2 and note that 2100 ppm for 30 s was effective as a disinfectant against murine hepatitis virus. This study aimed to determine the efficacy of aqueous HOCl in inactivating Phi6, a surrogate for SARS-CoV-2, on surfaces frequently encountered in consumer-facing environments such as food service dining areas, waiting rooms, hospital triage areas, and in-patient rooms. Tested parameters included inoculum matrix (ASTM formulated artificial saliva and tripartite load), surface type (stainless steel and vinyl), HOCl concentration (500 ppm and 1000 ppm), and exposure time (5 s, 30 s, and 60 s). Materials and Methods Phi6 Production Phi6 bacteriophage (HER102) production and Pseudomonas syringae pathovar phaseolicola (Pph) (HER1102) growth were performed in lysogeny (LC) broth [10 g/L NaCl (VWR, Radnor, PA), 10 g/L tryptone (VWR), 5 g/L yeast extract (VWR) ultrapure water, pH adjusted to 7.5] as previously described (Baker et al., 2022b). Briefly, one Pph colony was selected from an LC plate and grown overnight in 25 mL of LC broth with constant agitation. The following day, Phi6 was propagated by adding 200 µL Pph overnight stock and 100 µL of Phi6 stock (~ 10 log plaque forming units (PFU)/mL) to 5 mL of LC soft agar. The resulting mixture was poured onto an LC agar plate and distributed. This double agar overlay assay (DAL) is based on Kropinski et al. (2009). Once solidified (~ 15 min) the plates were inverted and incubated at 25 °C until a lacy appearance was present (~ 24 h). The soft agar layer was collected into 4 mL of LC broth with a 25 cm cell scraper (VWR) before vortexing and centrifuging for 10 min at 3000×g and 4 °C. The supernatant was filtered using a 0.45 µm sterile polyethersulfone syringe filter (Whatman, Buckinghamshire, United Kingdom) and stored at 4 °C. Phi6 stock was titered using the DAL assay. Inoculum Preparation—Artificial Saliva and Tripartite The artificial saliva matrix was chosen to mimic cough or sneeze ejecta and prepared according to ASTM E2721-16. In brief, the artificial saliva matrix consisted of 0.21 g/L KH2PO4 (Sigma-Aldrich, St. Louis, MO), 0.43 g/L K2HPO4 (Fisher Scientific, Loughborough, UK), 0.04 mg/L MgCl2·7H2O (Alfa Aesar, Ward Hill, MA), 0.11 g/L NH4Cl (VWR), 0.12 g/L (NH2)2CO (VWR), 0.13 g/L CaCl2 (VWR), 0.19 g/L KSCN (Acros Organics, Carlsbad, CA), 0.42 g/L NaHCO3 (Fisher Scientific), 0.88 g/L NaCl (VWR), 1.04 g/L KCl (VWR), and 3 g/L mucin (Sigma-Aldrich) at pH 7 (ASTM International, 2016; Owen et al., 2021). The tripartite matrix was chosen to mimic fecal material shed by infected individuals and prepared as per international standard ASTM E2197-17 (ASTM International, 2017). In brief, the tripartite matrix consisted of 0.8 g/L bovine mucin (Sigma-Aldrich), 2.5 g/L bovine serum albumin (VWR), and 3.5 g/L tryptone (VWR) (ASTM International, 2017; Kasloff et al., 2021; Riddell et al., 2020; Sattar et al., 2003). Phi6 stock was added to each matrix to obtain inoculum levels of approximately 7 log PFU/mL. Surface Preparation and Inoculation Coupons (5 cm × 5 cm, 25 cm2) made of stainless steel and vinyl were prepared as previously described (Baker et al., 2022b). Briefly, the stainless steel coupons were wrapped in aluminum foil and steam-sterilized at 121 °C, 15 psi for 30 min. Vinyl coupons could not be treated in this manner due to their physical composition. Prior to transfer trials, both surface types were exposed to UV light in a biosafety cabinet (30 min). After UV treatment, 100 µL of 7 log PFU/mL Phi6 inoculum in either artificial saliva or tripartite matrix was applied to the coupons in 8 to 12 spots to simulate droplets of bodily fluids. The droplets were allowed to dry for 45 min (i.e., the time at which the inoculum was visibly dry) in a biosafety cabinet under ambient conditions. HOCl Preparation HOCl was generated using the ChlorKing® HYPOGEN 5.0 at a pH of 6 and HOCl concentration of either 500 ppm or 1000 ppm (Chlorking, 2021). Briefly, the HYPOGEN 5.0 applies electrochemical activation of water and salt brine to produce slightly acidic or neutral electrolyzed water. The free chlorine concentration and pH of the HOCl solution was verified via the N,N-diethyl-p-phenylenediamine (DPD) method using a free chlorine kit (Hanna Instruments, Woonsocket, RI) and pH meter (Fisher Scientific), respectively. Surface Treatment and Elution After drying for 45 min in a biosafety cabinet, the coupons were sprayed with HOCl three times from a 30 cm distance to emulate spray bottle application of the HOCl solution. The approximate volume per spray was 1 mL. The HOCl remained on the coupons for 5 s, 30 s, or 60 s prior to elution with 2 mL of Dey-Engley neutralizing broth by repeated pipetting (five times), after which samples were diluted and plated via the DAL assay as described for Phi6 propagation. Statistical Analysis All experiments were performed in technical duplicates with two experimental trials. Log reductions were calculated as -log10FinalPFUInitialPFU, and data were analyzed in R Studio using a generalized linear model (GLM) with Quasipoisson error distributions due to heteroscedasticity, non-normality, and overdispersion (R Studio Team, 2020). More specifically, the Q–Q plot indicated non-normality of the data based on deviation of the tails from the reference line. Regarding heteroscedasticity, the ratio between the largest and smallest fitted residual is 2748.83 indicating significant deviation from the threshold (1.50) for homoscedasticity. To quantify overdispersion, the residual deviance was divided by the residual degrees of freedom to yield a value of 53.26. Since this value is much greater than one, a Quasipoisson distribution was applied in place of a Poisson distribution. The treatment means and their associated standard errors were calculated using estimated marginal means. Statistical differences between treatments were determined using multiple pairwise comparisons and visualized using compact letter display. The data were analyzed in R (R Core Team, 2021) using the base, base, ggplot2 (Wickham, 2016), emmeans (Length et al., 2021), tidyverse (Wickham et al., 2019), ggpubr (Kassambara, 2020), gdata (Warnes et al., 2022), rstatix (Kassambara, 2021), lme4 (Bates et al., 2015), lmertest (Kuznetsova et al., 2017), multcomp (Hothorn et al., 2008), and multcompView (Graves et al., 2019) packages. Results All raw data are plotted in Fig. 1, which gives the measured log reductions of Phi6 against the time in seconds for which HOCl was applied to the surface at either 500 or 1000 ppm. Figure 1 is faceted to show differences between surface type and inoculum matrix. Significant three-way interactions were observed for 1000 ppm, vinyl, and 60 s (P = 0.03) and 1000 ppm, tripartite, and 60 s (P = 0.0121). A significant two-way interaction between vinyl and 60 s was also observed (P = 0.0168). Due to the presence of significant interaction effects, conclusions about main effects cannot be made.Fig. 1 Raw data of log reductions based on HOCl concentration (shape), exposure time, surface material, and inoculum matrix The estimated mean log reductions with their 95% confidence intervals and the statistical groupings from the post-hoc analysis are shown in Fig. 2, where it can be observed that 1000 ppm HOCl resulted in significantly more (or equal) Phi6 reduction than 500 ppm HOCl. Additionally, at constant concentration, 60 s exposure times consistently led to more Phi6 reduction than 5 s exposure times. Significant differences between stainless steel and vinyl surface types were observed for concentration, exposure time, and inoculum matrix. Notably, the highest and lowest estimated mean log reductions were 3.31 (95% CI 3.14, 3.49) for stainless steel at 60 s and 1000 ppm HOCl in artificial saliva and 0.135 (95% CI 0.11, 0.17) for vinyl at 5 s and 1000 ppm HOCl in artificial saliva.Fig. 2 Generalized Linear Model with Quasipoisson Errors for HOCl inactivation of Phi6 virus. Compact letter format is used to designate statistical differences between treatments at P = 0.05 Discussion Past studies have explored the efficacy of OCl− inactivation of viruses. Saknimit et al. (1988) measured log reductions of canine coronavirus and two strains of murine hepatitis virus after 10 min exposure times at both 10 ppm and 100 ppm of sodium hypochlorite (NaOCl). In agreement with the present study, higher concentrations of the hypochlorite ion led to increased reduction of all viruses, with canine coronavirus undergoing 0.9 log and 1.05 log reductions at 10 ppm and 100 ppm NaOCl, respectively. A more marked difference between concentrations was observed for the murine hepatitis virus strains: 0.41 log reductions at 10 ppm HOCl and 2.54 log reductions at 100 ppm HOCl, on average (Saknimit et al., 1988). The present study reports estimated mean log reductions of 3.04 (95% CI 2.21, 4.17) for 1000 ppm HOCl and 1.32 (95% CI 0.81, 2.13) for 500 ppm HOCl at 60 s. At 5 s, estimated mean log reductions were 0.77(95% CI 0.41, 1.44) for 1,000 ppm HOCl and 0.17 (95% CI 0.04, 0.65) for 500 ppm HOCl. Park et al. (2007) investigated liquid- and fog-based HOCl inactivation of human norovirus and its surrogates (MS2 bacteriophage and murine norovirus) on stainless steel and ceramic coupons at three HOCl concentrations (18.8 ppm, 38 ppm, and 188 ppm) in a 1% human stool matrix. Others have also used MS2 bacteriophage as a surrogate for SARS-CoV-2 (Cadnum et al, 2020; Rockey et al., 2020). The required time for a 3 log reduction of MS2 was 5 min for stainless steel and unglazed ceramic at both 18.8 and 38 ppm HOCl. At 188 ppm HOCl, only 1 min of contact time was required to obtain a 3 log reduction of MS2 (Park et al., 2007). This reported log reduction of MS2 at 188 ppm HOCl and 60 s is similar to values observed in the present study for 1000 ppm HOCl at 60 s in tripartite [2.62 (95% CI 1.69, 4.06)] indicating that Phi6 may be a more conservative surrogate for SARS-CoV-2 than MS2 when evaluating virus inactivation by HOCl. It is worth noting that Park et al. (2007) used a 1% stool matrix while the present study used tripartite (and artificial saliva), so it is possible that the matrix composition also played a role in HOCl efficacy (Baker et al., 2022a; Bangiyev et al., 2021; Park et al., 2007). Hatanaka et al. (2021) tested SARS-CoV-2 inactivation with HOCl in suspension tests. The authors reported that incubation with a 125 ppm HOCl solution for 10 min or a 250 ppm HOCl solution for 5 min inactivated SARS-CoV-2 by more than 4 log tissue culture infectious dose (TCID50) per ml (Hatanaka et al., 2021). Unfortunately, the authors did not test sanitization of surfaces or within complex soils that SARS-CoV-2 would be realistically associated with. It is well-established that inactivation in suspension is often not equivalent to inactivation on a surface, especially in the presence of organic material (Lin et al., 2020). For instance, Kindermann et al. (2020) compared the efficacy of sodium hypochlorite in suspension and on carrier surfaces for inactivation of a lipid enveloped virus, bovine viral diarrhea virus (BVDV), among other viruses. The authors reported faster times to complete reduction in suspension tests (3 min) than on a stainless steel surface (5 min) for BVDV and 4500–6500 ppm free chlorine (Kindermann et al., 2020). Between 100 and 2000 infectious viral particles of SARS-CoV-2 is adequate to cause infection, and the viral load in sputum has been measured at a maximum of 2.35 × 109 copies per mL (Karimzadeh et al., 2021; Prentiss et al., 2022). Riddell et al. (2020) demonstrated that SARS-CoV-2 remains viable for 28 days when dried onto non-porous surfaces at loads and in matrices equivalent to those excreted by humans under ambient conditions (20 °C and 50% relative humidity), but not all studies agree (Baker & Gibson, 2022; Wölfel et al., 2020). Characterization of SARS-CoV-2 persistence on surfaces is critical to understanding transfer potential and subsequent disease risk as well as developing evidence-based cleaning and disinfection practices. Recently, Baker et al. (2022b) demonstrated bidirectional transfer of Phi6 suspended in artificial saliva and tripartite load between human skin and fomite surfaces such as touchscreen, vinyl, stainless steel, aluminum, wood, and plastic. The highest observed transfer rate from skin to surface was 22.0% (95% CI 12.8, 35.0) for touchscreen, and the highest observed transfer rate from surface to skin was 6.83% (95% CI 4.77, 9.69) for aluminum. Skin to surface transfer rates for vinyl and stainless steel were 10.9%, (95% CI 5.29, 21.3) and 2.5%, (95% CI 0.68, 9.03), respectively. Surface to skin transfer rates for vinyl and stainless steel were 4.69% (95% CI 3.03, 7.19) and 6.03% (95% CI 4.11, 8.76), respectively (Baker et al., 2022b). The low infective dose, high concentration in bodily fluids, and transferability between skin and surfaces emphasizes the importance of characterizing disinfectant efficacy and establishing proper instructions for use. Some limitations of the present study include the use of Phi6 as a surrogate for SARS-CoV-2, utilizing HOCl at a single pH value, and testing only two surfaces. Other surfaces that could be examined in future studies include touchscreen, laminate flooring, and painted cinderblock, as these surfaces are prevalent in both healthcare and other consumer-facing environments. Additional HOCl concentrations could be evaluated, but those used in the present study were chosen based on the hypochlorous generator’s manufacturer settings, as these concentrations would mimic the most likely implementation based on user feasibility. Exposure times investigated in the present study were chosen based on realistic expectations of sanitizer use. In practice, most sanitizers and disinfectants are sprayed on and immediately wiped off, and the study authors aimed to model the implications of that behavior. In the future, the impact of wiping the surface on pathogen removal should also be tested (Gibson et al., 2012). Additionally, evaluating longer contact times in the future could be useful to characterize tradeoffs between contact time and HOCl concentration. The level of virus reduction observed in the present study indicates that HOCl—at either 500 ppm or 1000 ppm—would be unlikely to inactivate SARS-CoV-2 to a degree which would prevent human illness given the known persistence and transfer properties of the virus. Extended contact times and sanitization with wiping should be tested. Other sanitization and disinfection methods may be explored in order to protect consumers from infection. Acknowledgements The authors would like to thank ChlorKing for providing the ChlorKing® HYPOGEN 5.0 system. We would also like to thank Dr. Aurelie Poncet for her guidance on appropriate statistical analysis. Disclaimer This document has not been formally reviewed by the U.S. Food and Drug Administration and should not be construed to represent Agency determination or policy. Author Contributions Conceptualization, CAB and KEG; Data Curation, ANH and CAB; Methodology, CAB; Formal Analysis, ANH; Investigation, ANH, SC, and CAB; Resources, KEG; Writing—Original Draft, ANH and CAB; Writing—Reviewing and Editing, ANH, SC, CAB, and KEG; Validation, CAB; Visualization, ANH; Project Administration, CAB; Supervision, CAB and KEG; Funding Acquisition, KEG. Funding This work was supported by Agriculture and Food Research Initiative Competitive Grant no. 2020-67017-32427 from the USDA National Institute of Food and Agriculture. Declarations Competing interests The authors have no competing interests to declare that are relevant to the content of this article. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Allen JD Feng W Corlin L Porteny T Acevedo A Schildkraut D Why are some people reluctant to be vaccinated for COVID-19? A cross-sectional survey among U.S. adults in May-June 2020 Preventive Medicine Reports 2021 24 101494 10.1016/j.pmedr.2021.101494 34277329 Anderson CE Boehm AB Transfer rate of enveloped and non-enveloped viruses between fingerpads and surfaces Applied and Environmental Microbiology 2021 10.1101/2021.06.22.449538 34469200 Aquino de Carvalho N Stachler EN Cimabue N Bibby K Evaluation of Phi6 persistence and suitability as an enveloped virus surrogate Environmental Science & Technology 2017 51 15 8692 8700 10.1021/acs.est.7b01296 28657725 ASTM International ASTM E2721–16, Standard practice for evaluation of effectiveness of decontamination procedures for surfaces when challenged with droplets containing human pathogenic viruses 2016 ASTM International ASTM International ASTM E2197–17, Standard quantitative disk carrier test method for determining bactericidal, virucidal, fungicidal, mycobactericidal, and sporicidal activities of chemicals 2017 ASTM International Baker CA Gibson KE Persistence of SARS-COV-2 on surfaces and relevance to the food industry Current Opinion in Food Science 2022 47 100875 10.1016/j.cofs.2022.100875 35784376 Baker CA Gutierrez A Gibson KE Factors impacting persistence of Phi6 bacteriophage, an enveloped virus surrogate, on fomite surfaces Applied and Environmental Microbiology 2022 10.1128/aem.02552-21 36165644 Baker CA Hamilton AN Chandran S Poncet AM Gibson KE Transfer of Phi6 bacteriophage between human skin and surfaces common to consumer-facing environments Journal of Applied Microbiology 2022 10.1111/jam.1580915 36083101 Bangiyev R Chudaev M Schaffner DW Goldman E Higher concentrations of bacterial enveloped virus Phi6 can protect the virus from environmental decay Applied and Environmental Microbiology 2021 10.1128/aem.01371-21 34406830 Bates D Mächler M Bolker B Walker S Fitting linear mixed-effects models usinglme4 Journal of Statistical Software 2015 10.18637/jss.v067.i01 Block MS Rowan BG Hypochlorous acid: A Review Journal of Oral and Maxillofacial Surgery 2020 78 9 1461 1466 10.1016/j.joms.2020.06.029 32653307 Cadnum J Li DF Jones LD Redmond SN Pearlmutter B Wilson B Donskey CJ Evaluation of ultraviolet-C light for rapid decontamination of airport security bins in the era of SARS-COV-2 Pathogens and Immunity 2020 5 1 133 10.20411/pai.v5i1.373 32582873 ChlorKing, Inc. (2021). Neutral Electrolyzed Water - ChlorKing. ChlorKing, Inc. Retrieved September 22, 2022 from https://tinyurl.com/neutralelectrolyzedwater〹 Dellanno C Vega Q Boesenberg D The antiviral action of common household disinfectants and antiseptics against murine hepatitis virus, a potential surrogate for SARS coronavirus American Journal of Infection Control 2009 37 8 649 652 10.1016/j.ajic.2009.03.012 19692148 Farah RFI Al-Haj Ali SN Electrolyzed water generated on-site as a promising disinfectant in the dental office during the COVID-19 pandemic Frontiers in Public Health 2021 9 629142 10.3389/fpubh.2021.629142 33996714 Fedorenko A Grinberg M Orevi T Kashtan N Survival of the enveloped bacteriophage Phi6 (a surrogate for SARS-COV-2) in evaporated saliva microdroplets deposited on glass surfaces Scientific Reports 2020 10.1038/s41598-020-79625-z 33376251 Frilander M Poranen M Bamford DH The large genome segment of dsRNA bacteriophage Phi6 is the key regulator in the in vitro minus and plus strand synthesis RNA 1995 1 510 518 7489512 Gallandat K Lantagne D Selection of a biosafety level 1 (BSL-1) surrogate to evaluate surface disinfection efficacy in ebola outbreaks: Comparison of four bacteriophages PLoS ONE 2017 12 5 e0177943 10.1371/journal.pone.0177943 28531182 Gibson KE Crandall PG Ricke SC Removal and transfer of viruses on food contact surfaces by cleaning cloths Applied and Environmental Microbiology 2012 78 9 3037 3044 10.1128/AEM.00027-12 22327573 Gonzalez CF Langenberg WG Van Etten JL Vidaver AK Ultrastructure of bacteriophage 6: Arrangement of the double-stranded RNA and envelope Journal of General Virology 1977 35 2 353 359 10.1099/0022-1317-35-2-353 874459 Graves, S., Piepho, H. P., Selzer, L. (2019). multcompView: Visualizations of Paired Comparisons. R package version 0.1–8. Retrieved from https://CRAN.R-project.org/package=multcompView Hatanaka N Yasugi M Sato T Mukamoto M Yamasaki S Hypochlorous acid solution is a potent antiviral agent against SARS-CoV-2 Journal of Applied Microbiology 2021 132 2 1496 1502 10.1111/jam.15284 34480823 Hothorn T Bretz F Westfall P Simultaneous inference in general parametric models Biometrical Journal 2008 50 3 346 363 10.1002/bimj.200810425 18481363 Kampf G Todt D Pfaender S Steinmann E Persistence of coronaviruses on inanimate surfaces and their inactivation with biocidal agents Journal of Hospital Infection 2020 104 3 246 251 10.1016/j.jhin.2020.01.022 32035997 Karimzadeh S Bhopal R Nguyen Tien H Review of infective dose, routes of transmission and outcome of covid-19 caused by the SARS-COV-2: Comparison with other respiratory viruses Epidemiology and Infection 2021 10.1017/s0950268821000790 33985614 Kasloff SB Leung A Strong JE Funk D Cutts T Stability of SARS-COV-2 on critical personal protective equipment Scientific Reports 2021 11 1 984 10.1038/s41598-020-80098-3 33441775 Kassambara, A. (2020). ggpubr: 'ggplot2' Based Publication Ready Plots. R package version 0.4.0. Retrieved from https://CRAN.R-project.org/package=ggpubr Kassambara, A. (2021). rstatix: Pipe-Friendly Framework for Basic Statistical Tests. R package version 0.7.0. Retrieved from https://CRAN.R-project.org/package=rstatix Kettle AJ Winterbourn CC Myeloperoxidase: A key regulator of neutrophil oxidant production Redox Report 1997 3 1 3 15 10.1080/13510002.1997.11747085 27414766 Kindermann J Karbiener M Leydold SM Knotzer S Modrof J Kreil TR Virus disinfection for biotechnology applications: Different effectiveness on surface versus in suspension Biologicals 2020 64 1 9 10.1016/j.biologicals.2020.02.002 32057565 Kropinski AM Mazzocco A Waddell TE Lingohr E Johnson RP Enumeration of bacteriophages by double agar overlay plaque assay Methods in Molecular Biology 2009 501 69 76 10.1007/978-1-60327-164-6_7 19066811 Kuznetsova A Brockhoff PB Christensen RH lmertest package: Tests in linear mixed effects models Journal of Statistical Software 2017 82 13 1 26 10.18637/jss.v082.i13 Length, R. V., Buerkner, P., Herve, M., Love, J., Miguez, F., Riebl, H., & Singmann, H. (2021). emmeans: Estimated Marginal Means, aka Least-Squares Means. R package version 1.7.5. Retrieved from https://CRAN.R-project.org/package=emmeans Lin Q Lim JY Xue K Yew PY Owh C Chee PL Loh XJ Sanitizing agents for virus inactivation and disinfection View 2020 1 2 e16 10.1002/viw2.16 34766164 Owen L Shivkumar M Laird K The stability of model human coronaviruses on textiles in the environment and during health care laundering mSphere 2021 6 2 e00316 10.1128/msphere.00316-21 33910996 Park GW Boston DM Kase JA Sampson MN Sobsey MD Evaluation of liquid- and fog-based application of Sterilox hypochlorous acid solution for surface inactivation of human norovirus Applied and Environmental Microbiology 2007 73 14 4463 4468 10.1128/aem.02839-06 17483283 Patel KP Vunnam SR Patel PA Krill KL Korbitz PM Gallagher JP Transmission of SARS-COV-2: An update of current literature European Journal of Clinical Microbiology & Infectious Diseases 2020 39 11 2005 2011 10.1007/s10096-020-03961-1 32638221 Prentiss M Chu A Berggren KK Finding the infectious dose for covid-19 by applying an airborne-transmission model to superspreader events PLoS ONE 2022 10.1371/journal.pone.0265816 35679278 R Core Team. (2021). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Retrieved from https://www.R-project.org/ Riddell S Goldie S Hill A Eagles D Drew TW The effect of temperature on persistence of SARS-COV-2 on common surfaces Virology Journal 2020 10.1186/s12985-020-01418-7 33028356 Rockey N Arts PJ Li L Harrison KR Langenfeld K Fitzsimmons WJ Humidity and deposition solution play a critical role in virus inactivation by heat treatment of N95 respirators mSphere 2020 10.1128/msphere.00588-20 33087516 RStudio Team. (2020). RStudio: Integrated Development for R. RStudio, PBC, Boston, MA. Retrieved from http://www.rstudio.com/ Saknimit M Inatsuki I Sugiyama Y Yagami K Virucidal efficacy of physico-chemical treatments against coronaviruses and parvoviruses of Laboratory Animals Experimental Animals 1988 37 3 341 345 10.1538/expanim1978.37.3_341 3416941 Sattar SA Springthorpe VS Adegbunrin O Zafer AA Busa M A disc-based Quantitative Carrier Test Method to assess the virucidal activity of chemical germicides Journal of Virological Methods 2003 112 1–2 3 12 10.1016/s0166-0934(03)00192-7 12951207 Schiffmann, A., & Conlon, D. (2019). Coronavirus Dashboard. Retrieved September 22, 2022from https://ncov2019.live/data Vidaver AK Koski RK Van Etten JL Bacteriophage Φ6: A lipid-containing virus of Pseudomonas phaseolicola Journal of Virology 1973 11 5 799 805 10.1128/jvi.11.5.799-805.1973 16789137 Warnes, G. R., Bolker, B., Gorjanc, G., Grothendieck, G., Korosec, A., Lumley, T., MacQueen, D., Magnusson, A., & Rogers, J. (2022). gdata: Various R Programming Tools for Data Manipulation. R package version 2.18.0.1. Retrieved from https://CRAN.R-project.org/package=gdata Whitworth C Mu Y Houston H Martinez-Smith M Noble-Wang J Coulliette-Salmond A Rose L Persistence of bacteriophage Phi 6 on porous and nonporous surfaces and the potential for its use as an Ebola virus or coronavirus surrogate Applied and Environmental Microbiology 2020 10.1128/aem.01482-20 32591388 Wickham H ggplot2: Elegant graphics for data analysis 2016 Springer-Verlag Wickham H Averick M Bryan J Chang W McGowan L François R Welcome to the Tidyverse Journal of Open Source Software 2019 4 43 1686 10.21105/joss.01686 Winter J Ilbert M Graf PCF Özcelik D Jakob U Bleach activates a redox-regulated chaperone by oxidative protein unfolding Cell 2008 135 4 691 701 10.1016/j.cell.2008.09.024 19013278 Wölfel R Corman VM Guggemos W Seilmaier M Zange S Müller MA Virological assessment of hospitalized patients with Covid-2019 Nature 2020 581 7809 465 469 10.1038/s41586-020-2196-x 32235945 Wood JP Richter W Sunderman M Calfee MW Serre S Mickelsen L Evaluating the environmental persistence and inactivation of MS2 bacteriophage and the presumed Ebola virus surrogate Phi6 using low concentration hydrogen peroxide vapor Environmental Science & Technology 2020 54 6 3581 3590 10.1021/acs.est.9b06034 32073830
PMC009xxxxxx/PMC9875168.txt	==== Front Soc Psychiatry Psychiatr Epidemiol Soc Psychiatry Psychiatr Epidemiol Social Psychiatry and Psychiatric Epidemiology 0933-7954 1433-9285 Springer Berlin Heidelberg Berlin/Heidelberg 36695916 2430 10.1007/s00127-023-02430-2 Original Paper Canadian news media coverage of suicide during the COVID-19 pandemic http://orcid.org/0000-0001-5376-9241 Whitley Rob [email protected] 12 http://orcid.org/0000-0003-2715-4475 Antebi Lara 1 1 grid.14709.3b 0000 0004 1936 8649 Douglas Research Centre, McGill University, 6875 LaSalle Boulevard, Montreal, QC H4H 1R3 Canada 2 grid.14709.3b 0000 0004 1936 8649 McGill University, Montreal, QC Canada 25 1 2023 2023 58 7 10871098 1 6 2022 12 1 2023 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Purpose The COVID-19 pandemic led to concerns about increases in suicidal behaviour. Research indicates that certain types of media coverage of suicide may help reduce suicidality (the Papageno effect), while other types may increase suicidality (the Werther effect). This study aimed to examine the tone and content of Canadian news articles about suicide during the first year of the pandemic. Methods Articles about suicide from Canadian news sources were collected and coded for adherence to responsible reporting of suicide guidelines. Articles which directly discussed suicidal behaviour in the COVID-19 context were identified and compared to other suicide articles in the same period. Lastly, a thematic analysis was conducted on the sub-sample of articles discussing suicide in the COVID-19 context. Results The sub-set of articles about suicide in the COVID-19 context (n = 103) contained significantly more putatively helpful content compared to non-COVID-19 articles (n = 457), such as including help information (56.3% Vs 23.6%), quoting an expert (68.0% Vs 16.8%) and educating about suicide (73.8% Vs 24.9%). This lower adherence among non-COVID-19 articles is concerning as they comprised over 80% of the sample. On the plus side, fewer than 10% of all articles provided monocausal, glamourized or sensational accounts of suicide. Qualitative analysis revealed the following three themes: (i) describing the epidemiology of suicidal behaviour; (ii) discussing self and communal care; and (iii) bringing attention to gaps in mental health care. Conclusion Media articles about suicide during the first year of the pandemic showed partial adherence to responsible reporting of suicide guidelines, with room for improvement. Keywords Suicide COVID-19 Media Newspaper Canada Mixed-methods MHCCissue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction Research suggests that certain types of media coverage of suicide can influence suicidal behaviour in the population [1, 2]. On the one hand, the Werther effect is a well-documented phenomenon describing a rise in suicides following extensive, repeated, and sensational news media coverage of suicide, particularly when reports focus on celebrity suicides, describe any suicide method in detail and present expert opinion and/or epidemiological facts in an alarming manner, devoid of discussion about suicide prevention [3–6]. It is hypothesized that this rise in suicides is facilitated through modelling and social learning, whereby vulnerable people learn to identify with the deceased by exposure to media coverage that implies that suicide is a common and acceptable solution to ongoing struggles, or even a heroic act worthy of emulation [4]. On the other hand, the media can be a vehicle for increased education, for example raising awareness that suicide is preventable, pointing to available suicide prevention and mental health care resources; as well as highlighting stories of hope and recovery through presentation of individual stories, or marshalling statistics and expert opinion focused on suicide prevention [3, 7–10]. Consumers of such media pieces may learn that helpful service-utilization, mental health recovery progress and mastery of crises are common processes among suicidal individuals, thus modelling such beneficial phenomena [3]. Indeed, such types of coverage can lead to a reduction in suicides, and is known as the Papageno effect. Rates of suicide are influenced by a multiplicity of complex factors [11]. The coronavirus (COVID-19) pandemic represents a period of potential concern for suicidal behaviour given reported increases in isolation, unemployment, domestic violence and other risk factors for suicide and adverse mental health [12]. As such, the importance of renewed suicide prevention efforts and other protective measures was emphasized at the start of the COVID-19 pandemic [12, 13]. Responsible reporting on suicide is one such protective measure that has been emphasized in Canada and beyond throughout the months of the pandemic [13–15]. Of note, various national and international organizations have developed responsible reporting of suicide recommendations which aim to diminish content associated with the Werther effect, while sometimes promoting the inclusion of putatively helpful content to foster help-seeking, suicide prevention and the Papageno effect [16–20]. These have been complemented by new specific recommendations from suicide experts related to reporting suicide during the COVID-19 pandemic, such as avoiding broad claims about the inevitability of suicide, as well as pointing to available resources and self-care strategies appropriate to the COVID-19 context [15]. A few studies have sought to assess news media coverage of suicide during the pandemic, but these have some limitations. For example, one UK study focused exclusively on reports of suicide deaths and attempts in the first four months of the pandemic [21], while another US study focused on a specific high-profile death of a New York physician [22]. To our knowledge, there has been a lack of research taking a broad-brush approach to suicide coverage over a longer period during the pandemic. As such, this study aims to fill this gap by examining the tone and content of suicide reporting in Canada over the first year of the COVID-19 pandemic. The primary objective was to assess articles’ adherence to responsible reporting of suicide guidelines, especially content putatively associated with a Werther effect. A secondary objective was to compare guideline adherence between articles directly focused on COVID-19 with articles not focused on COVID-19. A third objectivewa to identify prominent themes and narratives occurring in the subsample of articles focused on COVID-19 and suicide. Methods News media articles published over a 1-year period (1 March 2020–28 February 2021) were collected on a monthly basis using Factiva, an online database containing media articles from a wide variety of Canadian news sources. This 1-year period was chosen as lockdowns, social distancing and other public health measures were implemented across Canada in March 2020. Articles containing the keyword “suicide” were searched in over 40 top news sources, including three national newspapers (e.g. National Post), six online-only news websites (e.g. CBC News), and 38 high-circulation metropolitan or regional newspapers (e.g. Toronto Star). Those which mentioned suicide in passing or as a metaphor (e.g., “political suicide”) were excluded, as well as those which focused on suicide-bombing or assisted suicide/euthanasia. Duplicate articles (e.g., identical articles in the same news source) were omitted, however re-published articles (e.g., identical articles published across multiple different news sources) were included, given the relevance of considering frequency of coverage in studies of contagion [1, 3]. This study builds upon an ongoing media monitoring study of suicide in the Canadian news media, for which a more detailed description of the methods is published elsewhere [23]. In sum, articles were coded for adherence to suicide reporting recommendations, primarily examining putatively harmful content that has been associated with a Werther effect, while secondarily examining putatively helpful content that could be associated with a Papageno effect. These recommendations were selected based on the existing literature about the Werther effect and the Papageno effect [1, 3, 5, 10] and drew from existing guidelines relevant to the Canadian context [16, 18, 19], but were mainly based on Mindset guidelines [19], which have been used in several previous studies [8, 9, 23]. The Mindset guidelines were sponsored by the Mental Health Commission of Canada to encourage the responsible reporting of mental health and suicide and are available on a devoted website and as a short booklet, with over 5,000 distributed to journalists across Canada [23]. Mindset includes a series of bullet points related to writing about suicide that predominantly attempt to guide the journalist to avoid coverage that could lead to a Werther effect, for example “do not go into details about the method used” and “don’t romanticize the act…”. A few bullet points focus on content that might putatively foster a Papageno effect, for example, “do tell others considering suicide how they can get help”. However the Mindset guidelines do not include explicit bullet-points advising journalists to cover hopeful narratives of resilience, survival stories and mastery of crises, which are arguably the most important stories for suicide prevention and are instrumental in fostering a Papageno effect [3, 5–7]. We selected 11 variables based on these guidelines that have been used in previous studies, thus providing a basis for temporal comparison [8, 9, 23]. These consist of the following:The headline includes the word “suicide” or a synonym, for example, “shot himself” (yes/no). The article mentions the suicide method used (yes- alludes to method, e.g., asphyxiation; yes: a passing mention, e.g., hanging; yes- detailed description; no). The article mentions the suicide location (yes/no). The article gives a monocausal explanation of suicide (yes/no). The article glamourizes/romanticizes the death, e.g., describing it as “heroic” (yes/no). The article includes sensational language, for example, “suicide hotspot” (yes/no). The article uses discouraged words/phrases, for example, “committed” suicide (yes/no). The article provides help-seeking information, for example, a helpline number (yes/no). The article includes a quote by a suicide expert (yes/no). The article includes a quote by the suicide bereaved (yes/no). The article tries to educate the public about suicide (yes/no). Variables 1–7 aim to reduce putatively harmful content associated with a Werther effect, whereas variables 8, 9 and 11 have the potential to encourage putatively protective content, especially when focused on suicide prevention and treatments. Some guidelines suggest caution in presenting quotes by the bereaved, making this a more ambiguous variable [17, 18]. Each article was coded for further content characteristics, such as (i) the focus of the piece (e.g., suicide death/attempt, event/policy/research related to suicide); (ii) the suicide discussed (e.g., local individual/community member, high-profile person); (iii) demographic information (e.g., age/gender if applicable); and (iv) other general article characteristics (e.g., word count, date of publication). An additional binary code was added to bifurcate articles into those either (i) directly focused on suicide in the context of the COVID-19 pandemic; or (ii) focused/ discussed suicide independent of the COVID-19 pandemic. To achieve this bifurcation, all suicide articles were searched for the following key words: pandemic, coronavirus, COVID, COVID-19, virus and/or lockdown for further screening. Articles which directly discussed COVID-19 in relation to suicidal behaviour were put into category one, whereas those which were not related to COVID-19 or mentioned COVID-19 in passing (e.g., suicide inquest delayed due to COVID) were put into category two. All articles were retrieved and coded by the second author, with ongoing training and regular supervision by the first author, who is the principal investigator of an ongoing media monitoring study of suicide [8, 9, 23] As part of this ongoing media monitoring study, the authors have been involved in several double-coding exercises of sub-sets of news media articles about suicide using the questions listed above. These inter-rater reliability exercises led to an average k score of 0.83 (range 0.55–1.0) with perfect agreement on 6 variables, in a test of 20 different articles [23] Codes for each article were stored in Excel, then imported into R statistical software [24] at the end of the study period to calculate frequency counts, proportions, and statistical comparisons. Finally, an inductive thematic content analysis was conducted by the second author, again with supervision and training by the first author, to identify common themes, narratives and content in the sub-sample of articles about COVID-19 and suicide. Including an inductive sub-analysis is recommended practice in order to complement the rigid framework of using pre-defined quantitative codes [25]. The analysis followed standard procedure [26, 27], namely the following: (i) immersion in the dataset through reading and re-reading the sub-sample of articles; (ii) creating a list of specific themes or ‘open codes’ which appear across articles; (iii) comparing and collapsing of overlapping codes; and (iv) a final round of focused coding where finalized codes are applied and enumerated across the sub-sample. Results A total of 4,461 articles were retrieved over the 1-year period. 3,901 were excluded because they (i) mentioned suicide only in passing; (ii) used suicide metaphorically, for example, “political suicide,”; (iii) focused upon suicide-bombing; (iv) focused on euthanasia; or (v) were exact duplicates of a previous version in the same news source. This resulted in a final sample of 560 articles. Among these, 103 articles (18%) focused on COVID-19 and suicide, while 457 articles (82%) reported suicide independent of the COVID-19 situation. Quantitative results General article characteristics are presented in Table 1. In terms of article focus, 74.8% (n = 77) of COVID articles reported on events, policy or research related to suicide, with less than a quarter (n = 25, 24.3%) reporting on a suicide death/attempt. In contrast, non-COVID articles reported on a death/attempt in nearly 60% of cases (n = 272, 59.5%), with only a third focusing on events, policy or research (n = 151, 33.0%). In other words, COVID articles were over twice as likely to focus on events, policy and research than non-COVID articles.Table 1 Suicide article characteristics by COVID focus Variable Total (n = 560) n (%) COVID article (n = 103) Non-COVID article (n = 457) Scope National 33 (5.9%) 23 (5.0%) 10 (9.7%) Regional, large 339 (60.5%) 272 (59.5%) 67 (65.0%) Regional, small 46 (8.2%) 37 (8.1%) 9 (8.7%) Online only 142 (25.4%) 125 (27.4%) 17 (16.5%) Focus Death 241 (43.0%) 220 (48.1%) 21 (20.4%) Attempt 56 (10.0%) 52 (11.4%) 4 (3.9%) Event/policy/research 228 (40.7%) 151 (33.0%) 77 (74.8%) Other 35 (6.2%) 34 (7.4%) 1 (1.0%) Suicide Local person 181 (32.3%) 156 (34.1%) 25 (24.3%) High-profile person 39 (7.0%) 39 (8.5%) 0 (0.0%) Murder-suicide 82 (14.6%) 82 (17.9%) 0 (0.0%) Group of individuals 18 (3.2%) 14 (3.1%) 4 (3.9%) Fictional 2 (0.4%) 2 (0.4%) 0 (0.0%) Indigenous 85 (15.2%) 73 (16.0%) 12 (11.7%) Not focused on individuals 153 (27.3%) 91 (19.9%) 62 (60.2%) Age N/A 241 (43.0%) 176 (38.5%) 65 (63.1%) Child 28 (5.0%) 27 (5.9%) 1 (1.0%) Youth 108 (19.3%) 85 (18.6%) 23 (22.3%) Adult 175 (31.2%) 161 (35.2%) 14 (13.6%) Senior 8 (1.4%) 8 (1.8%) 0 (0.0%) Gender N/A 226 (40.4%) 156 (34.1%) 70 (68.0%) Male 263 (47.0%) 237 (51.9%) 26 (25.2%) Female 70 (12.5%) 64 (14.0%) 6 (5.8%) Other 1 (0.2%) 0 (0.0%) 1 (1.0%) Placement N/A (On-line) 234 (41.8%) 193 (42.2%) 41 (39.8%) Front 45 (8.0%) 37 (8.1%) 8 (7.8%) Inner 281 (50.2%) 227 (49.7%) 54 (52.4%) Variables related to suicide reporting recommendations are presented in Table 2. Overall, articles showed high adherence to certain guidelines, and low adherence to other guidelines. For instance, fewer than 10% of articles provided a monocausal (n = 39, 7.0%), glamourized (n = 31, 5.5%), or sensational (n = 47, 8.4%) account of suicide, however only around 1 in 3 articles attempted to educate about suicide (n = 190, 33.9%) or provide help-seeking information (n = 166, 29.6%). Only partial adherence was observed in other key variables, for example the suicide location was mentioned in 27% of articles (n = 151) and the method in 31.8% (n = 178). Comparing COVID and non-COVID articles, the chi-squared calculations showed significant differences for 4 of the 11 variables, with COVID related articles showing greater adherence on all 4 significant variables. For one, the COVID articles rarely included details about any method (n = 5, 4.9%), in contrast to the non-COVID articles which included details in over 10% of cases (n = 57, 12.5%). Interestingly, the COVID subsample showed significantly higher adherence to the guidelines related to putatively helpful content. Of note, over half included help information (n = 58, 56.3%), in contrast to 23.6% (n = 108) for general suicide articles. Further, nearly 70% of COVID articles quoted an expert (n = 70, 68.0%) and attempted to educate about suicide (n = 76, 73.8%), in contrast to 16.8% (n = 77) and 24.9% (n = 114), respectively, for non-COVID articles.Table 2 Adherence to suicide reporting recommendations by COVID focus Variable Total (n = 560) n (% Yes) COVID article (n = 103) X2* P value Non-COVID article (n = 457) Headline includes “suicide” or a synonym 297 (53.0%) 241 (52.7%) 56 (54.4%) 0.03642 0.8487 Mentions the suicide method 23.001* 4.04E-05 No 382 (68.2%) 292 (63.9%) 90 (87.4%) Yes, alludes to method 37 (6.6%) 32 (7.0%) 5 (4.9%) Yes, passing direct mention 79 (14.1%) 76 (16.6%) 3 (2.9%) Yes, in detail 62 (11.1%) 57 (12.5%) 5 (4.9%) Mentions the suicide location 151 (27.0%) 130 (28.4%) 21 (20.4%) 2.3773 0.1231 Gives a monocausal explanation of suicide 39 (7.0%) 33 (7.2%) 6 (5.8%) 0.083218 0.773 Glamourizes/romanticizes the death 31 (5.5%) 24 (5.3%) 7 (6.8%) 1.85E-28 0.7034 Includes sensational language 47 (8.4%) 40 (8.8%) 7 (6.8%) 0.20274 0.6525 Uses discouraged words 80 (14.3%) 69 (15.1%) 11 (10.7%) 1.0038 0.3164 Includes help information 166 (29.6%) 108 (23.6%) 58 (56.3%) 41.486* 1.19E-10 Quote by expert 147 (26.2%) 77 (16.8%) 70 (68.0%) 110.8* < 2.2e-16 Quote by bereaved 187 (33.4%) 160 (35.0%) 27 (26.2%) 2.5426 0.1108 Attempts to educate about suicide 190 (33.9%) 114 (24.9%) 76 (73.8%) 87.28* < 2.2e-16 Indicates significance (adjusted p-value cutoff with Bonferroni correction: 0.05/11 = 0.0045) Prior research on media reporting of suicide and mental illness indicates that articles about events, policy and research, as well as articles not focused on individuals, tend to be reported more positively [23, 28]. Given the high proportion of these articles in the COVID subsample, a stratified analysis within the COVID-19 sub-sample was conducted to compare guideline adherence between the following two types of articles (i) those focused on suicide incidents (deaths and attempts combined); and (ii) those focused on events, policy and /or research articles. As seen in Table 3, adherence to guidelines was generally higher for event, policy and research articles than for suicide incident reports, both for avoiding potentially harmful elements and actively including helpful content. Interestingly, the stratified analysis revealed that the event, policy and research articles related to suicide and COVID-19 had significantly higher proportions of positive elements, such as helpline information (n = 47, 61.0%), expert quotes (n = 67, 87.0%), and educative content (n = 68, 88.3%) about suicide, compared to the non-COVID reports. Likewise, for suicide incidents, COVID articles contained significantly higher proportions of educative content (n = 8, 32.0%) compared to non-COVID articles (n = 29, 10.7%).Table 3 Adherence to suicide reporting recommendations by COVID focus, for suicide incidents and event/policy/research articles Variable Suicide incident, n (% Yes) Non-COVID article (n = 272) COVID article (n = 25) X2 P value Headline 119 (43.8%) 10 (40.0%) 0.022859 0.8798 Method described 5.3713 0.1465 No 133 (48.9%) 15 (60.0%) Yes, alludes to method 28 (10.3%) 5 (20.0%) Yes, passing direct 64 (23.5%) 2 (8.0%) Yes, in detail 47 (17.3%) 3 (12.0%) Location 115 (42.3%) 18 (72.0%) 7.0209* 0.008056 Monocausal 27 (9.9%) 6 (24.0%) 3.2771 0.07025 Glamourize 24 (8.8%) 5 (20.0%) 2.1014 0.1472 Sensational 31 (11.4%) 3 (12.0%) 8.16E-32 1 Discouraged 47 (17.3%) 2 (8.0%) 0.83675 0.3603 Helpline 64 (23.5%) 11 (44.0%) 4.0563 0.04401 Expert 26 (9.6%) 3 (12.0%) 0.001721 0.9669 Bereaved 110 (40.4%) 16 (64.0%) 4.2826 0.0385 Educate 29 (10.7%) 8 (32.0%) 7.7024* 5.52E-03 Event/policy/research, n (% Yes) Variable Non-COVID article (n = 151) COVID article (n = 77) X2* P value Headline 96 (63.6%) 46 (59.7%) 0.17699 0.674 Method described 5.3978 0.1449 No 133 (88.1%) 74 (96.1%) Yes, alludes to method 4 (2.6%) 0 (0.0%) Yes, passing direct 10 (6.6%) 1 (1.3%) Yes, in detail 4 (2.6%) 2 (2.6%) Location 12 (7.9%) 3 (3.9%) 0.78223 0.3765 Monocausal 4 (2.6%) 0 (0.0%) 0.82369 0.3641 Glamourize 0 (0.0%) 1 (1.3%) 0.11826 0.7309 Sensational 6 (4.0%) 4 (5.2%) 0.0070522 0.9331 Discouraged 16 (10.6%) 9 (11.7%) 0.00065301 0.9796 Helpline 42 (27.8%) 47 (61.0%) 22.279* 2.36E-06 Expert 51 (33.8%) 67 (87.0%) 55.774 8.13E-14 Bereaved 41 (27.2%) 11 (14.3%) 4.0923* 0.043 Educate 85 (56.3%) 68 (88.3%) 22.258* 2.38E-06 *Indicates significance (adjusted p-value cutoff with Bonferroni correction: 0.05/11 = 0.0045) Qualitative results The qualitative analysis focused on the 103 COVID-related articles. Thirty-three of these were re-published content (identical articles appearing in more than one different news source). Since there was no added benefit to analysing multiple copies of these articles, each article was included only once, resulting in a total of 70 unique articles (listed in Appendix 1). The qualitative analysis revealed the following three key themes in the articles reporting suicide in the context of COVID-19: (i) describing the epidemiology of suicidal behaviour; (ii) discussing self-care and communal care; and (iii) bringing attention to gaps in mental health care (see Table 4).Table 4 Themes extracted from qualitative analysis Theme Number of articles Percent (N = 70) Describing the epidemiology of suicidal behaviour 45 64% Discussing self-care and communal care 45 64% Bringing attention to gaps in mental health care 35 50% Epidemiology of suicidal behaviour First, one of the most prominent themes across the articles was an epidemiological discussion of suicidal behaviour during the pandemic, appearing in 64% (n = 45) of articles. Articles reported on the prevalence of suicidal ideation, deaths, and attempts during the pandemic, citing survey results, ongoing research findings, as well as data from crisis centres. For instance, one article from December 2020 reported that “one in 10 Canadians have been experiencing recent thoughts or feelings of suicide up from 6% in the spring and 2.5% throughout pre-pandemic 2016” (A48). Others focused on data from distress lines, such as reporting on an increase in the number and intensity of suicide-related calls. Articles also speculated on the longer-term impacts of the pandemic on suicides, generally taking a cautious and balanced approach to reporting. For instance, articles typically included expert consultation to interpret research results, and made careful counterpoints about the certainty of these trends. For instance, one article reported rising suicidal thinking with key caveats: "It can take years for Canada to collect and release suicide statistics, making it impossible to know whether the pandemic is associated already with an increase in fatal self-harm. Juveria Zaheer, a psychiatrist and suicide researcher at the Centre for Addiction and Mental Health, said this was a key question, but that the answer is likely to be complicated. She noted the many factors that can influence a suicide trend, and warned of the harm that could be created by telling the public that a rise is to be expected. "If we're telling a story that there's an inevitability to an increased rate of suicide, that could send the message that there isn't hope or that there aren't services available," (A46) However, even when reporting on epidemiological research, around 20% of articles engaged in speculation which took a more sensational and scaremongering tone. For example, one article, which was re-published across nine major metropolitan newspapers, predicted that “Unemployment brought on by the COVID-19 lockdown could trigger as many as 2100 extra suicides this year and next… based on historic evidence that each one per cent rise in joblessness is associated with a similar one per cent hike in the number of people who die by suicide” (A20). Indeed, several headlines use language such as the pandemic ‘fuelling’ suicide rates (A6), causing a ‘spike’ in suicides or suicide-related calls (A13, A21, A24), or ‘triggering’ extra suicides (A20). Interestingly, such headlines were typically more sensational than the body of the article, which included a more in-depth and nuanced exploration of suicide trends. Self-care and communal care Another major theme appearing in 64% (n = 45) of the articles was self-care and communal care. Articles often emphasized that “help is available” (A32, A52, A55, A62) and to “reach out” if you or someone you know is struggling (A8, A29, A30, A34, A35, A43, A49). This often took the form of a list of resources at the end of the article, such as help-line numbers and websites. However, many articles also went into further detail about what individuals can do in terms of self-care, often soliciting the advice of experts in the fields of mental health and suicide. For example, one article states that it is “all of our responsibility to look out for one another”, quoting a branch representative from the Canadian Mental Health Association: “If you know someone that struggles, just check in with them. If you have a feeling in your gut about someone or see them express hopelessness, just have an honest conversation with them … People sometimes wonder if asking someone if they’ve contemplated suicide will put the idea in their head. That’s not true–it will actually provide relief”. (A31) Articles also emphasized the importance of maintaining general mental well-being during the pandemic, for example, by advising readers to stay connected with one another (A5, A46), to spend time outdoors (A15, A31), and to engage in meaningful activities (A8). Indeed, one article notes, “there are also protective factors that reduce the risk of mental anguish and suicide–meaning, purpose, hope and belonging – and people can work to increase those’. (A43). Bringing attention to gaps in mental health system Finally, another theme present in 50% (n = 35) of articles was bringing attention to gaps in the mental health system, with suicide often related to such gaps. For example, several articles described how the pandemic heightened the demand for mental health support, while also shutting down many services due to public health restrictions. However, these articles described this as an ongoing phenomenon because of an “ill-prepared” and “under-resourced” system (A14), which was already “not meeting people’s needs due to long waitlists, access issues, inequity and underfunding” (A48). This theme is especially salient in certain articles reporting on suicide deaths. For example, one article highlights the gaps faced by people with mental illness: “For him, the COVID-19 pandemic—with its broad shutdowns and cancellations of crucial counselling services—didn't cause his wife's death, but it exposed long-standing weaknesses in a system that failed her” (A36). Likewise, another report following a suicide cluster in an Indigenous community states that “the challenges faced by northern communities in accessing mental health services are not new, but leaders say that the pandemic has brought them back to the surface” (A18). Overall, many articles call for longer-term planning for suicide prevention, citing the pandemic as an important warning sign to increase resources and funding for mental health services. For example, one article about rising suicidal ideation concludes that “more needs to be done to overhaul the Canadian mental health system in the long run”—one that draws from data in the pandemic to be “more effective and more aligned with what people need" (A50). Discussion The results from this study indicate partial adherence to responsible reporting of suicide guidelines, with room for improvement in many key areas such as the following:(i) including more putatively helpful content such as help seeking information, which was only present in around 1 in 3 articles; (ii) focusing discussion on prevention and treatments, rather than decontextualized presentation of survey results and speculative projection of future trends; and (iii) omitting information related to method and location, which was present in a substantial minority of articles. Of note, articles about COVID-19 included significantly more putatively helpful elements, such as educating about suicide and help resources compared to non-COVID-19 articles. However, these COVID-19 articles comprised less than 20% of the media articles in the sample, meaning routine everyday reporting of suicide remained suboptimal during the pandemic. The qualitative analysis indicates that articles about COVID-19 and suicide often attempted to discuss epidemiological trends in a balanced manner, but sometimes discussed rising suicidality and speculated about future trends in an alarming fashion, without any content related to prevention or treatments. This has been linked to a Werther effect in previous studies [3]. That said, many articles included helpful information such as self-care advice or a list of suicide prevention resources, using the pandemic situation as a platform to discuss broader issues related to suicide, such as issues in mental health care. These elements align with specific COVID-19 responsible reporting of suicide recommendations written at the start of the pandemic, such as avoiding broad claims about the inevitability of suicide, pointing to available resources and promoting self-care [12–15]. Of note, a similar study using the same research design examined media coverage of suicide in Canada in the 12 months (2019–2020) before the pandemic [23] allowing for comparison of trends. Adherence to most guidelines remained stable, with some showing improvement in the pandemic year. For instance, articles including sensational language and those describing the location showed large decreases. There was also an increase in the proportion of articles which included help information, expert quotes, and educating about suicide, which is likely attributable to the COVID-19 articles. In terms of the suicide discussed, most categories appeared in similar proportions (e.g., local person, Indigenous); however, there were notably fewer articles about high-profile suicides and murder-suicides in the current study period. There are several possible interpretations to the improved coverage, especially among articles related to COVID-19. For one, the COVID-19 situation may have increased awareness of suicide as an issue among Canadian journalists, leading them to better utilize responsible reporting of suicide recommendations [11, 15]. Another explanation is that this continues a long-term trend of improved reporting of suicide and mental health issues in recent years [29, 30]. All this raises the following question: could the observed coverage contribute to any effect on actual suicide rates in Canada during the pandemic? One study found that suicides in Canada decreased from 10.1 deaths per 100,000 in the year before the pandemic (March 2019—February 2020) to 7.3 per 100,000 in the first year of the pandemic (March 2020—February 2021: the exact same time period of the present study), meaning an absolute difference of 1300 deaths [31].These findings converge with a cross-national interrupted time-series analysis, indicating a similar decrease in suicide rates during the first year of the pandemic in the vast majority of Western countries studied, including the USA, England, Australia, and New Zealand [32, 33]. These studies also indicated declining rates in several Canadian provinces included in the analysis, such as British Columbia, Manitoba and Alberta. Such a decrease was likely caused by a variety of intersecting factors including (i) governmental financial support to citizens negatively affected by COVID-19; (ii) the widespread provision of free or low-cost mental health supports and resources such as crises lines and therapeutic counselling; (iii) concerted action to raise awareness about effective self-care and mental health resilience strategies by community mental health organizations; (iv) heightened social capital and community spirit in the face of a common threat; and (v) the psychosocial benefits of working from home; including more time with family, less time commuting and fewer work-related stressors [31–33]. It is possible that the improved media coverage and partial adherence to responsible reporting of suicide guidelines observed in the present study may have interacted with the above-described factors to contribute in some manner to the observed decrease in Canadian suicides. However, the data (and study design) used in the present study do not allow for any such causal claims, and further experimental and epidemiological research is necessary to examine the relationship between media coverage and any possible Papageno effect. This study has some limitations. First, we only searched articles for the keyword “suicide”, meaning that we may have missed articles using other terms such as “took their own life”. Second, our focus on high-circulation Canadian newspapers left out other mainstream media such as television and radio, which may have shown other patterns of reporting. Third, there was a large difference in the number of articles about COVID, (n = 103) compared to non-COVID articles (n = 457). Such a magnitude of difference in cell sizes can contribute to a lower statistical power to detect true differences for some variables in Table 2. Fourth, we did not consider “new media” content such as social or alternative media, which would be needed for a more complete picture of suicide reporting [2, 10]. Fifth, the qualitative analysis was only applied to the COVID related articles, which the quantitative analysis had already identified as more adherent to guidelines; qualitative analysis of the non-COVID articles may have revealed more harmful content; however, this was not possible due to time and resource limitations. Perhaps the most important limitation relates to the coding schema used in this study, which was mainly inspired by the aforementioned Mindset guidelines. These may be weaker than other similar guidelines inasmuch as they do not include explicit bullet-points advising journalists to cover hopeful stories of resilience and mastery of crises, which are arguably the most important stories for suicide prevention and are instrumental in fostering a Papageno effect [3, 5, 10]. Future research should explicitly measure content related to these variables, which were omitted from the present study due to its reliance on Mindset. Conclusion The results from the present study indicate that the Canadian media showed partial adherence to responsible reporting of suicide recommendations, with the most adherent articles focused on suicide in the context of COVID-19. On the plus side, this adherence was higher than the year before the pandemic; however, there was still substantial room for improvement, especially in everyday routine articles about suicide and suicide deaths. Such improvement can be fostered by a multi-pronged approach including (i) educational outreach to practicing journalists, including organized presentations by suicide experts to newsrooms, journalism unions and media organizations; (ii) seminars, workshops and trainings about responsible reporting of suicide targeted at Canadian journalism schools and journalism students to ensure that the next generation of journalists responsibly reports suicide; and (iii) further distribution and promotion of responsible reporting of suicide guidelines produced by International and Canadian organizations (16–19) to newsrooms, journalism schools and media organizations. Of note, some of these guidelines may need to be revised to ensure that they explicitly recommend content associated with a Papageno effect, such as narratives of resilience, survival stories and mastery of crisis; which also should be communicated in the above-described educational efforts. All this may foster further improvements in suicide reporting in Canada. Appendix 1: Articles about COVID-19 and suicide for qualitative analysis (n = 70) Toronto Sun, “‘Everybody loved’ him; Anti-establishment activist’s life ends in tragic suicide”, 19 March 2020 Toronto Star, “Friends identify activist Derek Soberal as man who reportedly set himself on fire at Toronto gas station”, 19 March 2020 Winnipeg Free Press, “Man avoids jail due to COVID-19”, 31 March 2020 Toronto Star, “SIU clears police in activist’s death”, 15 April 2020 Globe and Mail, “Caring contacts: Reaching out to the vulnerable in a pandemic”, 16 April 2020 Calgary Sun, “Virus breeds despair; Pandemic fuelling suicide rate”, 17 April 2020 CBC News, “Crisis lines face volunteer, cash crunch even as COVID-10 drives surge in calls", 27 April 2020 Calgary Herald, “Suicide rates expected to rise as pandemic grinds on”, 27 April 2020 Niagara Falls Review, “Crisis lines see surge in demand, fewer staff”, 28 April 2020 Toronto Star, “What do we really know about suicide risk in the pandemic?”, 2 May 2020 Global News, “Saskatchewan chief concerned about mental health impacts of COVID-19 in First Nations", 3 May 2020 Calgary Herald, “Chiefs worry about effect of COVID-19 on mental health; First Nations struggling with stress, suicides”, 4 May 2020 Calgary Sun, “Calls to Calgary Distress Centre spike over COVID-19 stress and anxiety", 7 May 2020 The Guardian, “Suicide rates climb for young Nova Scotia men”, 8 May 2020 Regina Leader-Post, “Mental health calls on rise as new supports announced; Suicide prevention plan”, 9 May 2020 Globe and Mail, “Even when COVID-19 is beaten, the stress and depression of the pandemic will still be with us. How do we recover?”, 11 May 2020 Toronto Star, “Fear, isolation, depression: Many across the U.S. feel the mental health fallout of a pandemic", 13 May 2020 Saskatoon Star Phoenix, “COVID-19 compounds mental health fears in north”, 15 May 2020 Saskatoon Star Phoenix, “Mental-health related calls to police on rise over prior two weeks”, 21 May 2020 Regina Leader-Post, “Job loss may trigger 2,100 extra suicides; But link not direct; Get unemployed Canadians back to work, author says”, 4 June 2020 CTV News, “As COVID-19 stress builds, study warns of potential spike in suicides”, 4 June 2020 Calgary Sun, “‘What happened in the hospital’?; Family of B.C. man, who died in Regina, wants answers”, 8 June 2020 Calgary Herald, “Man found dead after visit to Regina hospital; Family says new protocols may have saved him”, 8 June 2020 Toronto Star, “Suicides could rise amid virus, study says; Research on pandemics finds link between unemployment, deaths”, 10 June 2020 Toronto Star, “Despite far fewer riders, suicide attempts remain significant problem on TTC network amid COVID-19, new records show”, 5 August 2020 CBC News, “25,000 Canadians hospitalized or killed by self-harm last year, research says”, 6 August 2020 CBC News, “Mental health experts in Thunder Bay Ont. say the community 'needs more' when it comes to suicide prevention”, 14 August 2020 CBC News, “National study says 'our children are not alright' under mounting stress of pandemic”, 1 September 2020 Kelowna Capital News, “Increase in calls due to pandemic: Interior Crisis Line Network”, 9 September 2020 CBC News, “You are never alone, Crisis Centre reminds everyone on World Suicide Prevention Day”, 10 September 2020 Kelowna Capital News, “Concerns over mental health loom as B.C. enters fall during COVID-19”, 10 September 2020 Calgary Sun, “Suicides not 'inevitable'; Open conversation one way to help: group”, 11 September 2020 Edmonton Sun, “Suicide is not 'inevitable'; More people turning to crisis centres since pandemic began, 83.8% increase in calls”, 11 September 2020 Saskatoon Star Phoenix, “Mother bares her grief on suicide prevention day; COVID-19 has exacerbated gaps in mental health care, advocate says”, 11 September 2020 CTV News, “Feds to invest $11.5 million in suicide prevention for marginalized communities”, 11 September 2020 Toronto Star, “He lost his wife. Now this man is fighting for supports during the pandemic that she did not receive”, 9 October 2020 Toronto Star, “Pandemic's effect on mental health must not be overlooked”, 10 October 2020 Globe and Mail, “Family demands B.C. inquiry after First Nations boy found dead in group home; The body of Driftpile Cree Nation teenager Traevon Desjarlais-Chalifoux, who was under the supervision of agency Xyolhemeylh, was undiscovered for four days”, 15 October 2020 Prince George Citizen, “Pandemic mental health crisis calls up, suicides down”, 11 November 2020 Calgary Herald, “Distress Centre seeks donations as COVID-19 increases demand”, 18 November 2020 Toronto Star, “The kids are in crisis—and COVID-19 is making it worse. In Canada, deteriorating youth mental health is leaving a generation in distress”, 23 November 2020 Toronto Star, “Seek help if you need it, Metrolinx says following string of suicide attempts on GO system”, 23 November 2020 Waterloo Region Record, “People urged to 'put in work' to build resiliency during pandemic”, 25 November 2020 Toronto Sun, “Help 'always' available; Metrolinx prioritizing suicide prevention”, 25 November 2020 Toronto Star, “'A pain to be understood'”, 28 November 2020 Globe and Mail, “Study finds jump in suicidal thoughts amid pandemic”, 3 December 2020 Victoria Times Colonist, “B.C. funds suicide-prevention programs for Indigenous youth, post-secondary students”, 4 December 2020 Prince George Citizen, “COVID’s second wave intensifying stress, anxiety”, 4 December 2020 Calgary Herald, “Beginning a new life; Addiction almost destroyed Rene Desjardins”, 5 December 2020 Toronto Star, “One in 10 Canadians say they've contemplated suicide since the pandemic began”, 5 December 2020 Toronto Star, “Suicide crisis calls mount during COVID-19 pandemic”, 7 December 2020 Globe and Mail, “Suicides up sharply on Toronto subway during pandemic”, 7 December 2020 Prince George Citizen, “Nurses deal with COVID ‘terror’ as stress, burnout, suicidal thinking rise”, 10 December 2020 CBC News, “Experts warn of pandemic's deepening impact on mental health as caseloads rise”, 17 December 2020 Toronto Star, “More young men in Western Canada died than expected last year—and not just because of COVID-19”, 4 January 2021 CBC News, “National organization urges N.S. to beef up mental health supports”, 5 January 2021 Toronto Sun, “When does it stop?; Man cuffed for lockdown violation takes own life”, 6 January 2021 CBC News, “Psychologist says 'come together effect' may have helped reduce suicides in Sask. in 2020”, 8 January 2021 CTV News, “Que. doctor's death by suicide raises alarms over COVID-19 stress”, 10 January 2021 Montreal Gazette, “Doctor's suicide a tragic wake-up call; Health workers need more than platitudes to combat the immense strain they're under”, 12 January 2021 Victoria Times Colonist, “In wake of suicide, focus turns to Goldstream Trestle safety”, 20 January 2021 Toronto Sun, “Driven to distress; Overcrowded buses and harried TTC drivers a sad reality”, 26 January 2021 Victoria Times Colonist, “Family of teen who died by suicide says psychiatrist appointment came too late”, 28 January 2021 Winnipeg Free Press, “Cascading crises leave Island Lake nations desperate for help”, 1 February 2021 CTV News, “Mental health help needed for post pandemic recovery: advocates”, 1 February 2021 Edmonton Sun, “A COVID-19 casualty we can't allow to happen", 4 February 2021 National Post, “Guilty plea by man who rammed Rideau Hall; Reservist; Seven weapons charges, one of causing mischief”, 6 February 2021 Global News, “‘Anxiety and depression are increasing’: Alberta doctor sees spike in mental health visits”, 6 February 2021 CBC News, “Many assumed suicides would spike in 2020. So far, the data tells a different story”, 8 February 2021 CBC News, “Parents of teen who took her own life say Fredericton ER failed her just days earlier”, 26 February 2021 Acknowledgements We would like to thank Anne-Marie Saucier and Sonora Grimsted for help in managing the data during the study, as well as assisting in locating relevant statistics and background articles. We would also like to thank the Mental Health Commission of Canada for funding the study. Author contributions All authors contributed to the study conception and design. RW oversaw data collection and analysis, and co-wrote the original manuscript, while taking a lead on the revision.. LA collected, analyzed and interpreted the data, and co-wrote the original manuscript. All authors read and approved the final revised manuscript. Funding The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was funded by the Mental Health Commission of Canada. Data availability The raw data for this study consists of newspaper articles. Many of these articles are behind a paywall on the news media websites listed in the paper, or only available via paid subscription to a database. Hence, we do not have the right to make these newspaper articles publicly available, as they were obtained through paid subscription to Factiva software in the current study. However, a list of the coded articles is available from the authors on reasonable request, which can be used to obtain the raw data behind the paywalls. Declarations Conflict of interest The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Ethical approval Not applicable as no human subjects. Data access The data for this study consists of news media articles published in Canadian news media that were obtained via paid subscription to the Factiva software. Due to reasons of copyright and proprietary, we cannot make this data publicly available in a supplemental file. ==== Refs References 1. Gould MS Suicide and the media Ann N Y Acad Sci 2001 932 1 200 224 10.1111/j.1749-6632.2001.tb05807.x 11411187 2. Sisask M Värnik A Media roles in suicide prevention: a systematic review Int J Environ Res Public Health 2012 9 1 123 138 10.3390/ijerph9010123 22470283 3. Niederkrotenthaler T Voracek M Herberth A Till B Strauss M Etzersdorfer E Eisenwort B Sonneck G Role of media reports in completed and prevented suicide: Werther v Papageno effects Br J Psychiatry 2010 197 3 234 243 10.1192/bjp.bp.109.074633 20807970 4. Whitley R Fink DS Santaella-Tenorio J Keyes KM Suicide mortality in Canada after the death of Robin Williams, in the context of high-fidelity to suicide reporting guidelines in the Canadian media Can J Psychiatry 2019 64 11 805 812 10.1177/0706743719854073 31181955 5. Niederkrotenthaler T Braun M Pirkis J Till B Stack S Sinyor M Tran US Voracek M Cheng Q Arendt F Scherr S Yip PSF Spittal MJ Association between suicide reporting in the media and suicide: systematic review and meta-analysis BMJ 2020 10.1136/bmj.m575 32188637 6. Yang AC Tsai SJ Yang CH Shia BC Fun JL Wang SJ Peng CK Huang NE Suicide and media reporting: a longitudinal and spatial analysis Soc Psychiatry Psychiatr Epidemiol 2013 48 427 435 10.1007/s00127-012-0562-1 22878833 7. Niederkrotenthaler T Reidenberg DJ Till B Gould MS Increasing help-seeking and referrals for individuals at risk for suicide by decreasing stigma: the role of mass media Am J Prev Med 2014 47 3 S235 S243 10.1016/j.amepre.2014.06.010 25145745 8. Creed M Whitley R Assessing fidelity to suicide reporting guidelines in Canadian news media: the death of Robin Williams Can J Psychiatry 2017 62 5 313 317 10.1177/0706743715621255 27600531 9. Carmichael V Whitley R Suicide portrayal in the Canadian media: examining newspaper coverage of the popular Netflix series ‘13 Reasons Why’ BMC Public Health 2018 18 1086 10.1186/s12889-018-5987-3 30170588 10. Sinyor M Schaffer A Nishikawa Y Redelmeier DA Niederkrotenthaler T Sareen J Levitt AJ Kiss A Pirkis J The association between suicide deaths and putatively harmful and protective factors in media reports CMAJ 2018 190 30 E900 907 10.1503/cmaj.170698 30061324 11. Mental Health Commission of Canada (2020) COVID-19 and suicide: Potential implications and opportunities to influence trends in Canada. Mental Health Commission of Canada. https://www.mentalhealthcommission.ca/wp-content/uploads/drupal/2020-11/covid19_and_suicide_policy_brief_eng.pdf. Accessed 3 August 2021. 12. Reger MA Stanley IH Joiner TE Suicide mortality and Coronavirus disease 2019—a perfect storm? JAMA Psychiat 2020 77 11 1093 1094 10.1001/jamapsychiatry.2020.1060 13. Gunnell D Appleby L Arensman E Hawton K John A Kapur N Khan M O’Connor RC Pirkis J Caine ED Chan LF Suicide risk and prevention during the COVID-19 pandemic Lancet Psychiatry 2020 7 6 468 471 10.1016/S2215-0366(20)30171-1 32330430 14. Public Health Agency of Canada (2020) The federal framework for suicide prevention – progress report 2020. Catalogue no. HP32–10e-E-PDF. Government of Canada. https://www.canada.ca/content/dam/hc-sc/documents/services/publications/healthy-living/2020-progress-report-federal-framework-suicide-prevention/2020-progress-report-federal-framework-suicide-prevention-eng.pdf. Accessed 3 August 2021. 15. Hawton K Marzano L Fraser L Hawley M Harris-Skillman E Lainez YX Reporting on suicidal behaviour and COVID-19—need for caution Lancet Psychiatry 2021 8 1 15 17 10.1016/S2215-0366(20)30484-3 33160581 16. World Health Organization Preventing suicide: a resource for media professionals 2008 Geneva World Health Organization 17. AFSP (n.d.) Recommendations for reporting on suicide. American Foundation for Suicide Prevention. https://afsp.org/for-journalists#resources-for-reporting-on-suicide. Accessed 3 August 2021. 18. Sinyor M Schaffer A Heisel MJ Picard A Adamson G Cheung CP Katz LY Jetly R Sareen J Media recommendations for reporting on suicide: 2017 update of the Canadian psychiatric association policy paper Can J Psychiatry 2017 63 3 182 196 10.1177/0706743717753147 19. Canadian Journalism Forum on Violence and Trauma Mindset: Reporting on mental health 2020 3 London Canadian Journalism Forum on Violence and Trauma 20. Samaritans (2013) Media guidelines for reporting suicide. Samaritans. https://www.samaritans.org/about-samaritans/media-recommendations/best-practice-suicide-reporting-tips/. Accessed 3 August 2021. 21. Marzano L Hawley M Fraser L Harris-Skillman E Lainez Y Hawton K Have news reports on suicide and attempted suicide during the COVID-19 pandemic adhered to guidance on safer reporting? A UK wide content analysis study Crisis 2022 10.1027/0227-5910/a000856 35383470 22. Lynn-Green EE Jaźwińska K Beckman AL Latham SR Violations of suicide-prevention guidelines in US media coverage of physician's suicide death during the COVID-19 pandemic Crisis 2021 10.1027/0227-5910/a000778 33944606 23. Antebi L Carmichael V Whitley R Assessing adherence to responsible reporting of suicide guidelines in the Canadian news media: a 1-year examination of day-to-day suicide coverage Can J Psychiatry 2020 65 9 621 629 10.1177/0706743720936462 32588647 24. Core R Team (2013) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna. https://www.R-project.org/. Accessed 3 August 2021. 25. Creswell JW Research design, qualitative and quantitative approaches 1996 New York SAGE 26. Braun V Clarke V Using thematic analysis in psychology Qual Res Psychol 2006 3 2 77 101 10.1191/1478088706qp063oa 27. Miles MB Huberman AM Qualitative data analysis: An expanded sourcebook 1994 New York SAGE 28. Whitley R Adeponle A Miller AR Comparing gendered and generic representations of mental illness in Canadian newspapers: an exploration of the chivalry hypothesis Soc Psychiatry Psychiatr Epidemiol 2015 50 325 333 10.1007/s00127-014-0902-4 24923412 29. Sinyor M Kiss A Williams M Zaheer R Pirkis J Heisel MJ Schaffer A Redelmeier DA Cheung AH Niederkrotenthaler T Changes in suicide reporting quality and deaths in Ontario following publication of national media guidelines Crisis 2021 42 5 378 385 10.1027/0227-5910/a000737 33241743 30. Whitley R Wang J Good news? A longitudinal analysis of newspaper portrayals of mental illness in Canada 2005 to 2015 Can J Psyc 2017 62 4 278 285 10.1177/0706743716675856 31. McIntyre RS Lui LM Rosenblat JD Ho R Gill H Mansur RB Teopiz K Liao Y Lu C Subramaniapillai M Nasri F Lee Y Suicide reduction in Canada during the COVID-19 pandemic: lessons informing national prevention strategies for suicide reduction JRSM 2021 114 10 473 479 10.1177/01410768211043186 34551280 32. Pirkis J Gunnell D Shin S Del Pozo-Banos M Arya V Aguilar PA Spittal MJ Suicide numbers during the first 9–15 months of the COVID-19 pandemic compared with pre-existing trends: An interrupted time series analysis in 33 countries E Clin Med 2022 51 101573 10.1016/j.eclinm.2022.101573 33. Pirkis J John A Shin S DelPozo-Banos M Arya V Analuisa-Aguilar P Spittal MJ Suicide trends in the early months of the COVID-19 pandemic: an interrupted time-series analysis of preliminary data from 21 countries The Lancet Psychiatry 2021 8 7 579 588 10.1016/S2215-0366(21)00091-2 33862016
PMC009xxxxxx/PMC9876760.txt	==== Front Silicon Silicon 1876-990X 1876-9918 Springer Netherlands Dordrecht 2302 10.1007/s12633-023-02302-z Review Paper Impact of Silicon on Plant Nutrition and Significance of Silicon Mobilizing Bacteria in Agronomic Practices http://orcid.org/0000-0002-2668-6165 Raza Taqi [email protected] [email protected] 1 Abbas Mazahir 2 Amna 3 Imran Shakeel 4 Khan Muhammad Yahya 4 Rebi Ansa 5 Rafie-Rad Zeinab 6 Eash Neal S. 1 1 grid.411461.7 0000 0001 2315 1184 Department of Biosystems Engineering & Soil Science, University of Tennessee, Knoxville, USA 2 grid.442867.b 0000 0004 0401 3861 University of Wah, Wah, Pakistan 3 grid.412621.2 0000 0001 2215 1297 Department of Plant Sciences, Quaid-I-Azam University Islamabad, Islamabad, Pakistan 4 grid.413016.1 0000 0004 0607 1563 UAF Sub Campus Burewala, University of Agriculture Faisalabad, Faisalabad, Pakistan 5 grid.66741.32 0000 0001 1456 856X Jianshui Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing, 100083 China 6 grid.412673.5 0000 0004 0382 4160 Department of Soil Science, Faculty of Agriculture, University of Zanjan, Zanjan, Iran 26 1 2023 2023 15 9 37973817 18 6 2022 13 1 2023 © The Author(s), under exclusive licence to Springer Nature B.V. 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Globally, rejuvenation of soil health is a major concern due to the continuous loss of soil fertility and productivity. Soil degradation decreases crop yields and threatens global food security. Improper use of chemical fertilizers coupled with intensive cultivation further reduces both soil health and crop yields. Plants require several nutrients in varying ratios that are essential for the plant to complete a healthy growth and development cycle. Soil, water, and air are the sources of these essential macro- and micro-nutrients needed to complete plant vegetative and reproductive cycles. Among the essential macro-nutrients, nitrogen (N) plays a significant in non-legume species and without sufficient plant access to N lower yields result. While silicon (Si) is the 2nd most abundant element in the Earth’s crust and is the backbone of soil silicate minerals, it is an essential micro-nutrient for some plants. Silicon is just beginning to be recognized as an important micronutrient to some plant species and, while it is quite abundant, Si is often not readily available for plant uptake. The manufacturing cost of synthetic silica-based fertilizers is high, while absorption of silica is quite slow in soil for many plants. Rhizosphere biological weathering processes includes microbial solubilization processes that increase the dissolution of minerals and increases Si availability for plant uptake. Therefore, an important strategy to improve plant silicon uptake could be field application of Si-solubilizing bacteria. In this review, we evaluate the role of Si in seed germination, growth, and morphological development and crop yield under various biotic and abiotic stresses, different pools and fluxes of silicon (Si) in soil, and the bacterial genera of the silicon solubilizing microorganisms. We also elaborate on the detailed mechanisms of Si-solubilizing/mobilizing bacteria involved in silicate dissolution and uptake by a plant in soil. Last, we discuss the potential of silicon and silicon solubilizing/mobilizing to achieve environmentally friendly and sustainable crop production. Keywords Silicon (Si) Silicon mobilizing bacteria Biotic and abiotic stress Crop production issue-copyright-statement© Springer Nature B.V. 2023 ==== Body pmcAuthor Contributions All authors contributed equally to design and conceptualize this study. Data collection and write-up were performed by [Taqi Raza, Mazahir Abbas, and Amna. The idea and concept of this review were given by Muhammad Yahya Khan. Reviewing, Editing and Improving (grammar and quality) of the manuscript were conducted by Neal Samuel Eash and Shakeel Imran. Literature search, citation, and formatting were carried out by Ansa Rabi and Zeinab Rafie-Rad. The first draft of the manuscript was written by [Taqi Raza] and all authors commented on previous versions of the manuscript. Funding The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Data Availability Not applicable. Declarations All authors read and approved the final manuscript. Ethics Approval All authors ethically approved the submission. Consent to Participate Yes. All permission granted. Consent for Publication Yes. All permission granted. Competing Interests/Conflict of Interest There is no conflict of interest between authors. Abbreviations Si Silicon AAPFCO Association of American plant food control officials AE Agricultural efficiency PE Physiological efficiency NUE Nitrogen use efficiency PGPR Plant growth promoting rhizobacteria RP Rocks phosphate YIB Yield increasing bacteria AMF Arbuscular mycorrhizal fungi SSB Silicone solubilizing bacteria PSB Phosphate solubilizing bacteria PSB Potassium solubilizing bacteria OM Organic matter TOC Total organic carbon RP Rock phosphate Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Liang Y Nikolic M Bélanger R Gong H Song A Silicon in Agriculture 2015 Dordrecht Springer 2. Haynes RJ A contemporary overview of silicon availability in agricultural soils J Plant Nutri Soil Sci 2014 177 831 844 10.1002/jpln.201400202 3. Heckman J Silicon and soil fertility The soil profile 2012 20 1 12 4. Heckman J Silicon: a beneficial substance Better Crops 2013 97 14 16 5. Viciedo DO de Mello PR Toledo RL dos Santos LCN Hurtado AC Nedd LLT Gonzalez LC Silicon supplementation alleviates ammonium toxicity in sugar beet (Beta vulgaris L.) J Soil Sci Plant Nutri 2019 19 413 419 10.1007/s42729-019-00043-w 6. Golubkina N Zayachkovsky V Sheshnitsan S Skrypnik L Antoshkina M Smirnova A Fedotov M Caruso G Prospects of the application of garlic extracts and selenium and silicon compounds for plant protection against herbivorous pests: a review Agriculture 2022 12 64 10.3390/agriculture12010064 7. Mostofa MG Rahman MM Ansary MMU Keya SS Abdelrahman M Miah MG Phan Tran LS Silicon in mitigation of abiotic stress-induced oxidative damage in plants Crit Rev Biotechnol 2021 41 918 934 10.1080/07388551.2021.1892582 33784900 8. Vasanthi N Saleena LM Raj SA Silicon in crop production and crop protection-A review Agri Rev 2014 35 14 23 10.5958/j.0976-0741.35.1.002 9. Frew A Weston LA Reynolds OL Gurr GM The role of silicon in plant biology: a paradigm shift in research approach Ann Bot 2018 121 1265 1273 10.1093/aob/mcy009 29438453 10. Zhang W Xie Z Lang D Cui J Zhang X Beneficial effects of silicon on abiotic stress tolerance in legumes J Plant Nutri 2017 40 2224 2236 10.1080/01904167.2017.1346127 11. Javaid T Farooq MA Akhtar J Saqib ZA Anwar-ul-Haq M Silicon nutrition improves growth of salt-stressed wheat by modulating flows and partitioning of Na+, Cl− and mineral ions J Plant Physiol Biochem 2019 141 291 299 10.1016/j.plaphy.2019.06.010 12. Yan G-C Nikolic M Ye M-J Xiao Z-X Liang Y-C Silicon acquisition and accumulation in plant and its significance for agriculture J Integr Agric 2018 17 2138 2150 10.1016/S2095-3119(18)62037-4 13. Abdel Latef AA Tran L-SP Impacts of priming with silicon on the growth and tolerance of maize plants to alkaline stress Front Plant Sci 2016 7 243 10.3389/fpls.2016.00243 27014283 14. Debona D Rodrigues FA Datnoff LE Silicon's role in abiotic and biotic plant stresses Annu Rev Phytopathol 2017 55 85 107 10.1146/annurev-phyto-080516-035312 28504920 15. Hussain I Parveen A Rasheed R Ashraf MA Ibrahim M Riaz S Afzaal Z Iqbal M Exogenous silicon modulates growth, physio-chemicals and antioxidants in barley (Hordeum vulgare L.) exposed to different temperature regimes SILICON 2019 11 2753 2762 10.1007/s12633-019-0067-6 16. Epstein E Silicon: its manifold roles in plants Ann Appl Biol 2009 155 155 160 10.1111/j.1744-7348.2009.00343.x 17. Ali S Rizwan M Ullah N Bharwana SA Waseem M Farooq MA Abbasi GH Farid M Physiological and biochemical mechanisms of silicon-induced copper stress tolerance in cotton (Gossypium hirsutum L.) Acta Physiol Plant 2016 38 1 11 10.1007/s11738-016-2279-3 18. Chaiwong N Prom-u-Thai C Bouain N Lacombe B Rouached H Individual versus combinatorial effects of silicon, phosphate, and iron deficiency on the growth of lowland and upland rice varieties Int J Mol Sci 2018 19 899 10.3390/ijms19030899 29562647 19. Tuna AL Kaya C Higgs D Murillo-Amador B Aydemir S Girgin AR Silicon improves salinity tolerance in wheat plants Environ Exp Bot 2008 62 10 16 10.1016/j.envexpbot.2007.06.006 20. Epstein E The anomaly of silicon in plant biology Proc Natl Acad Sci 1994 91 11 17 10.1073/pnas.91.1.11 11607449 21. Datnoff L (2002) in Abstract of second silicon in agriculture conference, 2002 22. Miyake Y Takahashi E Effect of silicon on the growth of solution-cultured cucumber plant Soil Sci Plant Nutr 1983 29 71 83 10.1080/00380768.1983.10432407 23. Onodera I Chemical studies on rice blast (1) J Sci Agric Soc 1917 180 606 617 24. Chen J Caldwell RD Robinson CA Steinkamp R Silicon: The estranged medium element Bull 2000 341 1 5 25. Elsokkary I Silicon as a beneficial element and as an essential plant nutrient: an outlook Alex Sci Exch 2018 39 534 550 26. Fox RL Silva JA Symptoms of Plant Malnutrition-Silicon, an Agronomically Essential Nutrient for Sugarcane 1978 Honolulu (HI) University of Hawaii 27. Pereira HS Korndörfer GH Vidal AdA Camargo MSd Silicon sources for rice crop Sci Agrí 2004 61 522 528 10.1590/S0103-90162004000500010 28. Richmond KE Sussman M Got silicon? The non-essential beneficial plant nutrient Curr Opin Plant Biol 2003 6 268 272 10.1016/S1369-5266(03)00041-4 12753977 29. Choy J-H Choi S-J Oh J-M Park T Clay minerals and layered double hydroxides for novel biological applications Appl Clay Sci 2007 36 122 132 10.1016/j.clay.2006.07.007 30. White AF Blum AE Schulz MS Bullen TD Harden JW Peterson ML Chemical weathering rates of a soil chronosequence on granitic alluvium: I. Quantification of mineralogical and surface area changes and calculation of primary silicate reaction rates Geochim Cosmochim Ac 1996 60 2533 2550 10.1016/0016-7037(96)00106-8 31. Gadd GM Metals, minerals and microbes: geomicrobiology and bioremediation Microbiol 2010 56 609 643 10.1099/mic.0.037143-0 32. Webley D Henderson ME Taylor IF The microbilogy of rocks and weathered stones J Soil Sci 1963 14 102 112 10.1111/j.1365-2389.1963.tb00935.x 33. Minden V Schaller J Venterink HO Plants increase silicon content as a response to nitrogen or phosphorus limitation: a case study with Holcus lanatus Plant Soil 2021 462 95 108 10.1007/s11104-020-04667-1 34. Chandrakala C Voleti S Bandeppa S Kumar NS Latha P Silicate solubilization and plant growth promoting potential of Rhizobium sp. isolated from rice rhizosphere SILICON 2019 11 2895 2906 10.1007/s12633-019-0079-2 35. Klotzbücher T Plant-available silicon in paddy soils as a key factor for sustainable rice production in Southeast Asia Basic Appl Ecol 2015 16 665 673 10.1016/j.baae.2014.08.002 36. Cornelis J-T Delvaux B Georg R Lucas Y Ranger J Opfergelt S Tracing the origin of dissolved silicon transferred from various soil-plant systems towards rivers: a review Biogeosci 2011 8 89 112 10.5194/bg-8-89-2011 37. Lavoie K Northup D Geomicrobiology of caves: a review Geomicrobiol J 2001 18 199 222 10.1080/01490450152467750 38. Sauro F Microbial diversity and biosignatures of amorphous silica deposits in orthoquartzite caves Sci Rep 2018 8 1 14 10.1038/s41598-018-35532-y 29311619 39. Vasanthi N Saleena L Raj SA Silica solubilization potential of certain bacterial species in the presence of different silicate minerals SILICON 2018 10 267 275 10.1007/s12633-016-9438-4 40. Zijlstra HJ Early diagenetic silica precipitation, in relation to redox boundaries and bacterial metabolism, in Late Cretaceous chalk of the Maastrichtian type locality Geol Mijnb 1987 66 343 355 41. Artyszak A Effect of silicon fertilization on crop yield quantity and quality—A literature review in Europe Plants 2018 7 54 10.3390/plants7030054 29986422 42. Mo Z Lei S Ashraf U Khan I Li Y Pan S Duan M Tian H Tang X Silicon fertilization modulates 2-acetyl-1-pyrroline content, yield formation and grain quality of aromatic rice J Cereal Sci 2017 75 17 24 10.1016/j.jcs.2017.03.014 43. Solanki P, Bhargava A, Chhipa H, Jain N, Panwar J (2015) In: Mahendra R, Caue R, Luiz M (eds) Nano-fertilizers and their smart delivery system, Springer International Publishing Switzerland 44. Meena V Dotaniya M Coumar V Rajendiran S Kundu S Rao AS A case for silicon fertilization to improve crop yields in tropical soils Proceedings of the National Academy of Sciences, India Section B: Biol Sci 2014 84 505 518 10.1007/s40011-013-0270-y 45. Etesami H, Jeong BR, Rizwan M (2020) In: Rupesh D, Durgesh K. Tripathi, Gea G (eds), Metalloids in Plants: Advances and Future Prospects, John Wiley & Sons Ltd. 46. Yeshe A, Gourkhede P, Vaidya P (2022) Chapter-5 Role and Application of Silicon in Agriculture. Current Res Soil Fert: 63 47. Sheng XF Zhao F He LY Qiu G Chen L Isolation and characterization of silicate mineral-solubilizing Bacillus globisporus Q12 from the surfaces of weathered feldspar Canad J Microbiol 2008 54 1064 1068 10.1139/W08-089 19096461 48. Puppe D Höhn A Kaczorek D Wanner M Wehrhan M Sommer M How big is the influence of biogenic silicon pools on short-term changes in water-soluble silicon in soils? Implications from a study of a 10-year-old soil–plant system Biogeosci 2017 14 5239 5252 10.5194/bg-14-5239-2017 49. Puppe D Review on protozoic silica and its role in silicon cycling Geoderma 2020 365 114224 10.1016/j.geoderma.2020.114224 50. Wu C Zhang L Mao L Zhu L Zhang Y Jiang H Zheng Y Liu X Efficiency of four extraction methods to assess the bioavailability of oxyfluorfen to earthworms in soil amended with fresh and aged biochar Agriculture 2022 12 765 10.3390/agriculture12060765 51. Farmer V Lumsdon D An assessment of complex formation between aluminium and silicic acid in acidic solutions Geochim Cosmochim 1994 58 3331 3334 10.1016/0016-7037(94)90088-4 52. Jurkić LM Cepanec I Pavelić SK Pavelić K Biological and therapeutic effects of ortho-silicic acid and some ortho-silicic acid-releasing compounds: New perspectives for therapy Nutr Metab 2013 10 1 12 10.1186/1743-7075-10-2 53. Bechtold MF Vest RD Plambeck L Jr Silicic acid from tetraethyl silicate hydrolysis. Polymerization and properties J Ameri Chemi Soci 1968 90 4590 4598 10.1021/ja01019a015 54. Swedlund PJ Miskelly GM McQuillan AJ Silicic acid adsorption and oligomerization at the ferrihydrite− water interface: Interpretation of ATR-IR spectra based on a model surface structure Langmuir 2010 26 3394 3401 10.1021/la903160q 20104911 55. Coradin T Lopez PJ Biogenic silica patterning: simple chemistry or subtle biology? Chem Bio Chem 2003 4 251 259 10.1002/cbic.200390044 12672103 56. Ke Y, Stroeve P (2005) Polymer-layered silicate and silica nanocomposites. (Elsevier). 57. Cornelis JT Delvaux B Soil processes drive the biological silicon feedback loop Funct Ecol 2016 30 1298 1310 10.1111/1365-2435.12704 58. Vandevenne F Barão L Ronchi B Govers G Meire P Kelly E Struyf E Silicon pools in human impacted soils of temperate zones Global Biogeochem Cycles 2015 29 1439 1450 10.1002/2014GB005049 59. Haynes RJ What effect does liming have on silicon availability in agricultural soils? Geoderma 2019 337 375 383 10.1016/j.geoderma.2018.09.026 60. Sommer M Kaczorek D Kuzyakov Y Breuer J Silicon pools and fluxes in soils and landscapes—a review J Plant Nutri Soil Sci 2006 169 310 329 10.1002/jpln.200521981 61. White AF Vivit DV Schulz MS Bullen TD Evett RR Aagarwal J Biogenic and pedogenic controls on Si distributions and cycling in grasslands of the Santa Cruz soil chronosequence, California Geochim Cosmochim 2012 94 72 94 10.1016/j.gca.2012.06.009 62. Creevy KE Austad SN Hoffman JM O’Neill DG Promislow DE The companion dog as a model for the longevity dividend Cold Spring Harb Perspect Med 2016 6 a026633 10.1101/cshperspect.a026633 26729759 63. Tubaña BS, Heckman JR (2015) In: Fabrício AR, Lawrence ED (eds) Silicon in soils and plants, Springer International Publishing Switzerland 64. Laruelle GG et al. (2009) Anthropogenic perturbations of the silicon cycle at the global scale: Key role of the land‐ocean transition. Global Biogeochem Cycles 23 65. Brindavathy R (2022) In: Aydin B, Mostafa S (eds) Mineral Formation by Microorganisms, Springer, Cham 66. Fomina M Skorochod I Microbial interaction with clay minerals and its environmental and biotechnological implications Minerals 2020 10 861 10.3390/min10100861 67. Li GL Zhou CH Fiore S Yu WH Interactions between microorganisms and clay minerals: New insights and broader applications Appl Clay Sci 2019 177 91 113 10.1016/j.clay.2019.04.025 68. Etesami H Jeong BR Contribution of arbuscular mycorrhizal fungi, phosphate–solubilizing bacteria, and silicon to P uptake by plant: a review Front Plant Sci 2021 12 1355 10.3389/fpls.2021.699618 69. Thies JE Grossman JM In: Norman UF, Andrew SB Erick F Hans H Olivier H Mark L Cheryl P Jules P Pedro S Nteranya S Janice T(eds) Biological approaches to sustainable soil systems 2006 Boca Raton CRC Press 70. Patrick S Holding A The effect of bacteria on the solubilization of silica in diatom frustules J Appl Bacteriol 1985 59 7 16 10.1111/j.1365-2672.1985.tb01768.x 71. Sheng M Tang M Chen H Yang B Zhang F Huang Y Influence of arbuscular mycorrhizae on photosynthesis and water status of maize plants under salt stress Mycorrhiza 2008 18 287 296 10.1007/s00572-008-0180-7 18584217 72. Bist V Niranjan A Ranjan M Lehri A Seem K Srivastava S Silicon-solubilizing media and its implication for characterization of bacteria to mitigate biotic stress Front plant sci 2020 11 28 10.3389/fpls.2020.00028 32194577 73. Driks A Maximum shields: the assembly and function of the bacterial spore coat Trends Microb 2002 10 251 254 10.1016/S0966-842X(02)02373-9 74. Liu W Xu X Wu X Yang Q Luo Y Christie P Decomposition of silicate minerals by Bacillus mucilaginosus in liquid culture Environ Geochem Health 2006 28 133 140 10.1007/s10653-005-9022-0 16528584 75. Sumitha S Phyto-mediated photo catalysed green synthesis of silver nanoparticles using Durio zibethinus seed extract: antimicrobial and cytotoxic activity and photocatalytic applications Molecules 2018 23 3311 10.3390/molecules23123311 30551671 76. Shahbazi Y Moosavy M-H Physico-mechanical and antimicrobial properties of quince seed mucilage supplemented with titanium dioxide and silicon oxide nanoparticles J Nanomed Res 2019 4 157 163 77. Whitehead KA Colligon J Verran J Retention of microbial cells in substratum surface features of micrometer and sub-micrometer dimensions Colloids Surf, B 2005 41 129 138 10.1016/j.colsurfb.2004.11.010 78. Dasgupta N Arora SK Ramphal R fleN, a gene that regulates flagellar number in Pseudomonas aeruginosa J Bacteriol 2000 182 357 364 10.1128/JB.182.2.357-364.2000 10629180 79. Ghorbani-Choghamarani A Azadi G Tahmasbi B Hadizadeh-Hafshejani M Abdi Z Phosphorus Sulfur Silicon Relat Elem 2014 189 433 439 10.1080/10426507.2013.844140 80. Yin L Wang S Tanaka K Fujihara S Itai A Den X Zhang S Silicon-mediated changes in polyamines participate in silicon-induced salt tolerance in S orghum bicolor L Plant Cell Environ 2016 39 245 258 10.1111/pce.12521 25753986 81. Zellner W Datnoff L (2020) In: Youssef R, Patrick du J Patrick B Stefania De P Giuseppe C (eds) Silicon as a biostimulant in agriculture, 1st edn. Burleigh Dodds Science Publishing 82. Bist N Sircar A Yadav K Holistic review of hybrid renewable energy in circular economy for valorization and management Environ Techn Innov 2020 20 101054 10.1016/j.eti.2020.101054 83. Dhiman P Fascinating role of silicon to combat salinity stress in plants: An updated overview Plant Physiol Biochem 2021 162 110 123 10.1016/j.plaphy.2021.02.023 33667964 84. Armbruster CE Hodges SA Smith SN Alteri CJ Mobley HL Arginine promotes Proteus mirabilis motility and fitness by contributing to conservation of the proton gradient and proton motive force Microbiologyopen 2014 3 630 641 10.1002/mbo3.194 25100003 85. Shivaraj S Mandlik R Bhat JA Raturi G Elbaum R Alexander L Tripathi DK Deshmukh R Sonah H Outstanding questions on the beneficial role of silicon in crop plants Plant Cell Physiol 2022 63 4 18 10.1093/pcp/pcab145 34558628 86. Currie HA Perry CC Silica in plants: biological, biochemical and chemical studies Annals Bot 2007 100 1383 1389 10.1093/aob/mcm247 87. Neethirajan S Gordon R Wang L Potential of silica bodies (phytoliths) for nanotechnology Tren Biotechnol 2009 27 461 467 10.1016/j.tibtech.2009.05.002 88. Dhiman G Kumar V Seagull optimization algorithm: Theory and its applications for large-scale industrial engineering problems Knowl Based Syst 2019 165 169 196 10.1016/j.knosys.2018.11.024 89. Jensen DM Morgan TR Marcellin P Pockros PJ Reddy KR Hadziyannis SJ Ferenci P Ackrill AM Willems B Early identification of HCV genotype 1 patients responding to 24 weeks peginterferon α-2a (40 kd)/ribavirin therapy Hepatology 2006 43 954 960 10.1002/hep.21159 16628671 90. Al-Karaki GN Nursery inoculation of tomato with arbuscular mycorrhizal fungi and subsequent performance under irrigation with saline water Sci Hortic 2006 109 1 7 10.1016/j.scienta.2006.02.019 91. Li H Zhu Y Hu Y Han W Gong H Beneficial effects of silicon in alleviating salinity stress of tomato seedlings grown under sand culture Acta Physiol Plant 2015 37 1 9 10.1007/s11738-015-1818-7 92. Hafez EM, Osman HS, El-Razek UAA, Elbagory M, Omara AE-D, Eid MA, Gowayed SM (2021) Foliar-applied potassium silicate coupled with plant growth-promoting rhizobacteria improves growth, physiology, nutrient uptake and productivity of faba bean (Vicia faba L.) irrigated with saline water in salt-affected soil. Plants 10: 894 93. Ribeiro IDA Volpiano CG Vargas LK Granada CE Lisboa BB Passaglia LMP Use of mineral weathering bacteria to enhance nutrient availability in crops: a review Front Plant Sci 2020 11 590774 10.3389/fpls.2020.590774 33362817 94. Saad M Abo-Koura HA Improvement of sorghum (Sorghum bicolor l. Moench) growth and yield under drought stress by inoculation with Bacillus cereus and foliar application of potassium silicate Environ Biodiv Soil Sec 2018 2 205 221 95. Tubana BS Babu T Datnoff LE A review of silicon in soils and plants and its role in US agriculture: history and future perspectives Soil Sci 2016 181 393 411 10.1097/SS.0000000000000179 96. Barker W Welch S Chu S Banfield J Experimental observations of the effects of bacteria on aluminosilicate weathering Am Min 1998 83 1551 1563 10.2138/am-1998-11-1243 97. Raturi G Sharma Y Rana V Thakral V Myaka B Salvi P Singh M Dhar H Deshmukh R Exploration of silicate solubilizing bacteria for sustainable agriculture and silicon biogeochemical cycle Plant Physiol Biochem 2021 166 827 838 10.1016/j.plaphy.2021.06.039 34225007 98. Drever JI The effect of land plants on weathering rates of silicate minerals Geochim Cosmochim 1994 58 2325 2332 10.1016/0016-7037(94)90013-2 99. Lambers H Mougel C Jaillard B Hinsinger P Plant-microbe-soil interactions in the rhizosphere: an evolutionary perspective Plant Soil 2009 321 83 115 10.1007/s11104-009-0042-x 100. Chen W Luo L He L-Y Wang Q Sheng X-F Distinct mineral weathering behaviors of the novel mineral-weathering strains Rhizobium yantingense H66 and Rhizobium etli CFN42 Appl Environ Microbiol 2016 82 4090 4099 10.1128/AEM.00918-16 27129959 101. Wang RR Wang Q He LY Qiu G Sheng XF Isolation and the interaction between a mineral-weathering Rhizobium tropici Q34 and silicate minerals World J Microbiol Biotechnol 2015 31 747 753 10.1007/s11274-015-1827-0 25716616 102. Yanni YG, Rizk RY, Corich V, Squartini A, Ninke K, Philip-Hollingsworth S, Orgambide G, Bruijn FD, Stoltzfus J, Buckley D, Schmidt TM (1997) in Opportunities for biological nitrogen fixation in rice and other non-legumes. Natural endophytic association between Rhizobium leguminosarum bv. trifolii and rice roots and assessment of its potential to promote rice growth. (Springer) pp. 99–114. 103. Banfield JF Hamers RJ Processes at minerals and surfaces with relevance to microorganisms and prebiotic synthesis Rev Mineral Geochem 1997 35 81 122 104. Dove MT Keen DA Hannon AC Swainson IP Direct measurement of the Si–O bond length and orientational disorder in the high-temperature phase of cristobalite Phys Chem Miner 1997 24 311 317 10.1007/s002690050043 105. Zhu Y Gong H Beneficial effects of silicon on salt and drought tolerance in plants Agron Sustain Dev 2014 34 455 472 10.1007/s13593-013-0194-1 106. Vayssiere J-L Petit PX Risler Y Mignotte B Commitment to apoptosis is associated with changes in mitochondrial biogenesis and activity in cell lines conditionally immortalized with simian virus 40 Proc Natl Acad Sci 1994 91 11752 11756 10.1073/pnas.91.24.11752 7972136 107. Yue H Mo W Li C Zheng Y Li H The salt stress relief and growth promotion effect of Rs-5 on cotton Plant Soil 2007 297 139 145 10.1007/s11104-007-9327-0 108. Etesami H Can interaction between silicon and plant growth promoting rhizobacteria benefit in alleviating abiotic and biotic stresses in crop plants? Agri Ecosys Environ 2018 253 98 112 10.1016/j.agee.2017.11.007 109. Raza T, Villalobos SdLS, Shehzad M, Imran S, da Silva DJH (2020) PGP Characterization of rhizobacteria associated with apple gourd (Praecitrullus fistulosus L.). Pak J Agri Res 33: 926 110. Torbeck RL Saedi N Optimization of laser tattoo removal: optical clearing agents and multiple same-day treatments via the R0 and R20 methods Curr Dermatol Reps 2016 5 136 141 10.1007/s13671-016-0139-4 111. Meena V Dotaniya M Coumar V Rajendiran S Kundu S Subba Rao A A case for silicon fertilization to improve crop yields in tropical soils Proceedings of the National Academy of Sciences, India Section B: Biol Sci 2014 84 505 518 10.1007/s40011-013-0270-y 112. Singh T Singh P Singh A Silicon significance in crop production: Special consideration to rice: An overview J Pharm Innov 2021 10 223 229 10.22271/tpi.2021.v10.i3d.5776 113. Shin J Bioresorbable pressure sensors protected with thermally grown silicon dioxide for the monitoring of chronic diseases and healing processes Nat Biomed Eng 2019 3 37 46 10.1038/s41551-018-0300-4 30932064 114. Gondil VS Asif M Bhalla TC Optimization of physicochemical parameters influencing the production of prodigiosin from Serratia nematodiphila RL2 and exploring its antibacterial activity Biotech 2017 7 1 8 115. Al-Kumaim NH Alhazmi AK Mohammed F Gazem NA Shabbir MS Fazea Y Exploring the impact of the COVID-19 pandemic on university students’ learning life: An integrated conceptual motivational model for sustainable and healthy online learning Sustain 2021 13 2546 10.3390/su13052546 116. Lee K-E Adhikari A Kang S-M You Y-H Joo G-J Kim J-H Kim S-J Lee I-J Isolation and characterization of the high silicate and phosphate solubilizing novel strain Enterobacter ludwigii GAK2 that promotes growth in rice plants Agron 2019 9 144 10.3390/agronomy9030144 117. Adhikari A, Lee K-E, Khan MA, Kang S-M, Adhikari B, Imran M, Jan R, Kim K-M, Lee I-J (2020) Effect of silicate and phosphate solubilizing Rhizobacterium Enterobacter ludwigii GAK2 on Oryza sativa L. under cadmium stress. J Microbiol Biotechnol 30(1): 118–126 118. Mendoza-Arroyo GE, Chan-Bacab MJ, Aguila-Ramírez RN, Ortega-Morales BO, Canché Solís RE, Chab-Ruiz AO, Cob-Rivera KI, Dzib-Castillo B, Tun-Che RE, Camacho-Chab JC (2020) Inorganic phosphate solubilization by a novel isolated bacterial strain Enterobacter sp. ITCB-09 and its application potential as biofertilizer. Agri 10: 383 119. Liang Y Wong J Wei L Silicon-mediated enhancement of cadmium tolerance in maize (Zea mays L.) grown in cadmium contaminated soil Chemo 2005 58 475 483 10.1016/j.chemosphere.2004.09.034 120. Li Z Delvaux B Yans J Dufour N Houben D Cornelis JT Phytolith-rich biochar increases cotton biomass and silicon-mineralomass in a highly weathered soil J Plant Nutri Soil Sci 2018 181 537 546 10.1002/jpln.201800031 121. Mehrabanjoubani P Abdolzadeh A Sadeghipour HR Aghdasi M Silicon affects transcellular and apoplastic uptake of some nutrients in plants Pedosphere 2015 25 192 201 10.1016/S1002-0160(15)60004-2 122. Sakurai G Satake A Yamaji N Mitani-Ueno N Yokozawa M Feugier FG Ma JF In silico simulation modeling reveals the importance of the Casparian strip for efficient silicon uptake in rice roots Plant Cell Physiol 2015 56 631 639 10.1093/pcp/pcv017 25673476 123. Liang Y Shen Q Shen Z Ma T Effects of silicon on salinity tolerance of two barley cultivars J Plant Nutri 1996 19 173 183 10.1080/01904169609365115 124. Jarvis S The uptake and transport of silicon by perennial ryegrass and wheat Plant Soil 1987 97 429 437 10.1007/BF02383233 125. Savant NK Korndörfer GH Datnoff LE Snyder GH Silicon nutrition and sugarcane production: a review J Plant Nutri 1999 22 1853 1903 10.1080/01904169909365761 126. Deshmukh R Bélanger RR Molecular evolution of aquaporins and silicon influx in plants Funct Ecol 2016 30 1277 1285 10.1111/1365-2435.12570 127. Guntzer F Keller C Meunier J-D Benefits of plant silicon for crops: a review Agron Sustain Dev 2012 32 201 213 10.1007/s13593-011-0039-8 128. Shen D Microbial diversity and application of microbial products for agricultural purposes in China Agric Ecosyst Environ 1997 62 237 245 10.1016/S0167-8809(96)01132-2 129. Kang S-M Isolation and characterization of a novel silicate-solubilizing bacterial strain Burkholderia eburnea CS4-2 that promotes growth of japonica rice (Oryza sativa L. cv. Dongjin) Soil Sci Plant Nutri 2017 63 233 241 130. Batista BD Singh BK Realities and hopes in the application of microbial tools in agriculture Microb Biotechnol 2021 14 1258 1268 10.1111/1751-7915.13866 34156754 131. Garg KK, Jain D, Rajpurohit D, Kushwaha HS, Daima HK, Stephen BJ, Singh A, Mohanty SR (2021) Agricultural significance of silica nanoparticles synthesized from a silica solubilizing bacteria. Comments Inorg Chem 1–17 132. Hendry KR Marron AO Vincent F Conley DJ Gehlen M Ibarbalz FM Quéguiner B Bowler C Competition between silicifiers and non-silicifiers in the past and present ocean and its evolutionary impacts Front Mar Sci 2018 5 22 10.3389/fmars.2018.00022 133. Rezakhani L Motesharezadeh B Tehrani MM Etesami H Mirseyed Hosseini H Effect of silicon and phosphate-solubilizing bacteria on improved phosphorus (P) uptake is not specific to insoluble P-fertilized sorghum (Sorghum bicolor L.) plants J Plant Growth Regul 2020 39 239 253 10.1007/s00344-019-09978-x 134. Bharti V, Dotaniya M, Shukla S, Yadav V (2017) In: Jay SS, Gamini S (eds) Agro-environmental sustainability, 1st edn. Springer, Cham 135. Sindhu V Chatterjee R Santhoshkumar G Sinha T Enrichment of Organic Manures and Their Utilization in Vegetable Crops Curr J App Sci Technol 2020 39 10 24 10.9734/cjast/2020/v39i3230998 136. Pratheesh P, Lal S, Tuvikene R, Manickam S, Sudheer S (2020) In: Ali AR, Ajar NY, Neelam Y (eds) New and future developments in microbial biotechnology and bioengineering. 1st edn. Elsevier, Amsterdam, Netherlands 137. Raza T Khan MY Nadeem SM Imran S Qureshi KN Mushtaq MN Sohaib M Schmalenberger A Eash NS Biological management of selected weeds of wheat through co-application of allelopathic rhizobacteria and sorghum extract Biol Cont 2021 164 104775 10.1016/j.biocontrol.2021.104775 138. Rajput VD Effects of silicon and silicon-based nanoparticles on rhizosphere microbiome, plant stress and growth Biology 2021 10 791 10.3390/biology10080791 34440021 139. Raza T Qureshi KN Imran S Eash NS Bortone I Associated health risks from heavy metal-laden effluent into point drainage channels in Faisalabad Pakistan Pak J Agri Res 2021 34 3 487 494 140. Verma KK Interactive role of silicon and plant–rhizobacteria mitigating abiotic stresses: A new approach for sustainable agriculture and climate change Plants 2020 9 1055 10.3390/plants9091055 32824916 141. Kumar A, Patel JS, Bahadur I, and Meena VS (2016) In: Vijay SM, Bihari RM, Jay PV, Ram SM (eds). Potassium solubilizing microorganisms for sustainable agriculture. 1st edn. Springer, India 142. Kumawat N, Kumar R, Khandkar U, Yadav R, Saurabh K, Mishra J, Dotaniya M, and Hans H (2019) In: Bhoopander G, Ram P, Qiang-Sheng W, Ajit V (eds) Biofertilizers for sustainable agriculture and environment. 1st edn. Springer, Cham 143. Shah AA Yasin NA Akram K Ahmad A Khan WU Akram W Akbar M Ameliorative role of Bacillus subtilis FBL-10 and silicon against lead induced stress in Solanum melongena Plant Physiol Biochem 2021 158 486 496 10.1016/j.plaphy.2020.11.037 33298367 144. Paulraj P Balakrishnan K Rajendran RRMV Alagappan B Investigation on recent research of mechanical properties of natural fiber reinforced polymer (NFRP) materials Mater Plast 2021 58 100 118 10.37358/MP.21.2.5482 145. Dollinger J Schacht VJ Gaus C Grant S Effect of surfactant application practices on the vertical transport potential of hydrophobic pesticides in agrosystems Chemosphere 2018 209 78 87 10.1016/j.chemosphere.2018.06.078 29913402 146. Zhou J Sun Y Xiao H Ma Q Si L Ni L Wu L Silicon uptake and translocation in low-silica rice mutants investigated by isotope fractionation Agron J 2021 113 2732 2741 10.1002/agj2.20597 147. Brindavathy R Dhara N Rajasundari K Biodissolution of silica by silicon bacteria in sugarcane rhizosphere Res J Agr Sci 2012 3 1042 1044 148. Chaiwong N Rerkasem B Pusadee T Prom-u-thai C Silicon application improves caryopsis development and yield in rice J Sci Food Agric 2021 101 220 228 10.1002/jsfa.10634 32627188 149. Bocharnikova E Loginov S Matychenkov V Storozhenko P Silicon fertilizer efficiency Russ Agric Sci 2010 36 446 448 10.3103/S1068367410060157 150. Shamim M, Kumar M, Pal AK, Kumar RR, and Jha V (2019) In: Shamim M, Kumar M, Pal AK, Kumar RR, Jha V (eds) Biofertilizers and biopesticides in sustainable agricultur, 1st edn. Apple Academic Press 151. Van der Weijden CH, Middelburg JJ, Van Ganns P (1989) Early diagenetic silica precipitation, in relation to redox boundaries and bacterial metabolism, in late Cretaceous Chalk of the Maastrichtian type locality. Geol Mijnb 68: 263-270 152. Mattey M The production of organic acids Crit Rev Biotechnol 1992 12 87 132 10.3109/07388559209069189 1733523 153. Vandevivere P Welch S Ullman W Kirchman DL Enhanced dissolution of silicate minerals by bacteria at near-neutral pH Microb Ecol 1994 27 241 251 10.1007/BF00182408 24190338 154. Machado RMA, Serralheiro RP (2017) Soil salinity: effect on vegetable crop growth. Management practices to prevent and mitigate soil salinization. Sci Hortic 3: 30 155. Nanayakkara U Uddin W Datnoff L Application of silicon sources increases silicon accumulation in perennial ryegrass turf on two soil types Plant Soil 2008 303 83 94 10.1007/s11104-007-9488-x 156. Kalia A and Kaur H in Nanoscience for sustainable agriculture (2019). In: Ramesh N P, Nidhi C, Chittaranjan K (eds) Nano-biofertilizers, 1st edn. Springer, Chem 157. Kannan N Raj SA Occurrence of silicate solubilizing bacteria in rice ecosystem Madras Agri J 1998 85 47 49 158. Shivaraj S Mandlik R Bhat JA Raturi G Elbaum R Alexander L Tripathi DK Deshmukh R Sonah H Outstanding questions on the beneficial role of silicon in crop plants Plant Cell Physiol 2021 63 1 4 18 10.1093/pcp/pcab145 159. Schwab F Zhai G Kern M Turner A Schnoor JL Wiesner MR Barriers, pathways and processes for uptake, translocation and accumulation of nanomaterials in plants–Critical review Nanotoxicology 2016 10 257 278 10.3109/17435390.2015.1048326 26067571 160. Li L Luo Y Li R Zhou Q Peijnenburg WJ Yin N Yang J Tu C Zhang Y Effective uptake of submicrometre plastics by crop plants via a crack-entry mode Nat Sustain 2020 3 929 937 10.1038/s41893-020-0567-9 161. Limmer MA Wise P Dykes GE Seyfferth AL Silicon decreases dimethylarsinic acid concentration in rice grain and mitigates straighthead disorder Environ Sci Techn 2018 52 4809 4816 10.1021/acs.est.8b00300 162. Lovisolo C Hartung W Schubert A Whole-plant hydraulic conductance and root-to-shoot flow of abscisic acid are independently affected by water stress in grapevines Funct Plant Biol 2002 29 1349 1356 10.1071/FP02079 32688733 163. Marafon AC, Endres L (2013) Silicon: fertilization and nutrition in higher plants. Embrapa Tabuleiros Costeiros-Artigo em periódico indexado (ALICE). Rev Cienc Agrar 56(4): 380–388 164. Mandlik R Thakral V Raturi G Shinde S Nikolić M Tripathi DK Sonah H Deshmukh R Significance of silicon uptake, transport, and deposition in plants J Exp Bot 2020 71 6703 6718 10.1093/jxb/eraa301 32592476 165. Motomura H Fujii T Suzuki M Silica deposition in abaxial epidermis before the opening of leaf blades of Pleioblastus chino (Poaceae, Bambusoideae) Ann Bot 2006 97 513 519 10.1093/aob/mcl014 16464877 166. Kumar S Elbaum R Interplay between silica deposition and viability during the life span of sorghum silica cells New Phyto 2018 217 1137 1145 10.1111/nph.14867 167. Nassif N Livage J From diatoms to silica-based biohybrids Chem Soci Rev 2011 40 849 859 10.1039/C0CS00122H 168. Zhou K-G Electrically controlled water permeation through graphene oxide membranes Nature 2018 559 236 240 10.1038/s41586-018-0292-y 29995867 169. Harley A Gilkes R Factors influencing the release of plant nutrient elements from silicate rock powders: a geochemical overview Nutr Cycl Agroecosystems 2000 56 11 36 10.1023/A:1009859309453 170. Manning DA Mineral sources of potassium for plant nutrition A review Agron Sustain Dev 2010 30 281 294 10.1051/agro/2009023 171. Anda M Shamshuddin J Fauziah C Improving chemical properties of a highly weathered soil using finely ground basalt rocks CATENA 2015 124 147 161 10.1016/j.catena.2014.09.012 172. Ryan PR Delhaize E Jones DL Function and mechanism of organic anion exudation from plant roots Ann Rev Plant Biol 2001 52 527 10.1146/annurev.arplant.52.1.527 173. Aoki M Fujii K Kitayama K Environmental control of root exudation of low-molecular weight organic acids in tropical rainforests Ecosyst 2012 15 1194 1203 10.1007/s10021-012-9575-6 174. Vives-Peris V de Ollas C Gómez-Cadenas A Pérez-Clemente RMJPcr. Root exudates: from plant to rhizosphere and beyond Plant Cell Reprt 2020 39 3 17 10.1007/s00299-019-02447-5 175. Richter DdB, Oh N-H, Fimmen R, and Jackson J (2007) In: Zoe GC, Julie LW (eds) The rhizosphere, Elsevier, Academic Press 176. Bennett P Rogers J Choi W Hiebert F Silicates, silicate weathering, and microbial ecology Geomicrobiol J 2001 18 3 19 10.1080/01490450151079734 177. Samuels T, Bryce C, Landenmark H, Marie‐Loudon C, Nicholson N, Stevens AH, Cockell C (2020) Microbial weathering of minerals and rocks in natural environments. Biogeochemical cycles: Environ Ecol Stat 59–79 178. Ranalli G, Zanardini E, and Sorlini C (2009) Biodeterioration–including cultural heritage. 179. Zhu Y Duan G Chen B Peng X Chen Z Sun G Mineral weathering and element cycling in soil-microorganism-plant system Sci China Earth Sci 2014 57 888 896 10.1007/s11430-014-4861-0 180. Smith KS Ferry JG Prokaryotic carbonic anhydrases FEMS Microbiol Rev 2000 24 335 366 10.1111/j.1574-6976.2000.tb00546.x 10978542 181. Xiao L Hao J Wang W Lian B Shang G Yang Y Liu C Wang S The up-regulation of carbonic anhydrase genes of Bacillus mucilaginosus under soluble Ca2+ deficiency and the heterologously expressed enzyme promotes calcite dissolution Geomicrobiol J 2014 31 632 641 10.1080/01490451.2014.884195 182. Adeleke R Nwangburuka C Oboirien B Origins, roles and fate of organic acids in soils: A review S Afr J Bot 2017 108 393 406 10.1016/j.sajb.2016.09.002 183. Torres MA West AJ Nealson K Microbial acceleration of olivine dissolution via siderophore production Procedia Environ Sci 2014 10 118 122 184. Uroz S Calvaruso C Turpault M-P Frey-Klett P Mineral weathering by bacteria: ecology, actors and mechanisms Trends Microbiol 2009 17 378 387 10.1016/j.tim.2009.05.004 19660952 185. Zavarzina DG Oxidative biotransformation of biotite and glauconite by alkaliphilic anaerobes: the effect of Fe oxidation on the weathering of phyllosilicates Chem Geol 2016 439 98 109 10.1016/j.chemgeo.2016.06.015 186. Chandrakala C Voleti S Bandeppa S Sunil Kumar N Latha P Silicate solubilization and plant growth promoting potential of Rhizobium sp. isolated from rice rhizosphere SILICON 2019 11 2895 2906 10.1007/s12633-019-0079-2 187. Hu L Xia M Lin X Xu C Li W Wang J Zeng R Song Y Earthworm gut bacteria increase silicon bioavailability and acquisition by maize Soil Biol Biochem 2018 125 215 221 10.1016/j.soilbio.2018.07.015 188. Sauer D Saccone L Conley DJ Herrmann L Sommer M Review of methodologies for extracting plant-available and amorphous Si from soils and aquatic sediments Biogeochem 2006 80 89 108 10.1007/s10533-005-5879-3 189. Belton DJ Deschaume O Perry CC An overview of the fundamentals of the chemistry of silica with relevance to biosilicification and technological advances The FEBS J 2012 279 1710 1720 10.1111/j.1742-4658.2012.08531.x 22333209 190. Perry CC Keeling-Tucker T Aspects of the bioinorganic chemistry of silicon in conjunction with the biometals calcium, iron and aluminium J Inorg Biochem 1998 69 181 191 10.1016/S0162-0134(97)10017-4 9629678 191. Wonisch H Gérard F Dietzel M Jaffrain J Nestroy O Boudot J-P Occurrence of polymerized silicic acid and aluminum species in two forest soil solutions with different acidity Geoderma 2008 144 435 445 10.1016/j.geoderma.2007.11.022 192. Cornelis J-T Delvaux B Cardinal D André L Ranger J Opfergelt S Tracing mechanisms controlling the release of dissolved silicon in forest soil solutions using Si isotopes and Ge/Si ratios Geochim Cosmochim Acta 2010 74 3913 3924 10.1016/j.gca.2010.04.056 193. Matichenkov V and Bocharnikova E in Studies in plant science (2001). The relationship between silicon and soil physical and chemical properties. (Elsevier) pp. 209–219. 194. Lucas Y and Chauvel A (1992) Soil formation in tropically weathered terrains. Regolith exploration geochemistry in tropical and subtropical terrains.. 57–77 195. Savant NK Datnoff LE Snyder GH Depletion of plant-available silicon in soils: A possible cause of declining rice yields Commun Soil Sci Plant Anal 1997 28 1245 1252 10.1080/00103629709369870 196. El-Tayeb M Response of barley grains to the interactive e. ect of salinity and salicylic acid Plant Growth Regu 2005 45 215 224 10.1007/s10725-005-4928-1 197. Gunes A Inal A Bagci E Coban S Sahin O Silicon increases boron tolerance and reduces oxidative damage of wheat grown in soil with excess boron Biol Plant 2007 51 571 574 10.1007/s10535-007-0125-6 198. Roboredo MC Pessoa AA A branch-and-cut algorithm for the discrete (r∣ p)-centroid problem Eur J Oper Res 2013 224 101 109 10.1016/j.ejor.2012.07.042 199. Rains D Epstein E Zasoski R Aslam M Active silicon uptake by wheat Plant Soil 2006 280 223 228 10.1007/s11104-005-3082-x 200. Meena H Meena RS Assessment of sowing environments and bio-regulators as adaptation choice for clusterbean productivity in response to current climatic scenario Bangladesh J Bot 2017 46 241 244 201. Mali M Aery CN Silicon effects on nodule growth, dry-matter production, and mineral nutrition of cowpea (Vigna unguiculata) J Plant Nutrit Soil Sci 2008 171 835 840 10.1002/jpln.200700362 202. Desplanques V Cary L Mouret J-C Trolard F Bourrie G Grauby O Meunier J-D Silicon transfers in a rice field in Camargue (France) J Geochem Explor 2006 88 190 193 10.1016/j.gexplo.2005.08.036 203. Pei Z Ming D Liu D Wan G Geng X Gong H Zhou W Silicon improves the tolerance to water-deficit stress induced by polyethylene glycol in wheat (Triticum aestivum L.) seedlings J Plant Growth Reg 2010 29 106 115 10.1007/s00344-009-9120-9 204. Ma J Takahashi E Effect of silicon on the growth and phosphorus uptake of rice Plant soil 1990 126 115 119 10.1007/BF00041376 205. Alzahrani Y Kuşvuran A Alharby HF Kuşvuran S Rady MM The defensive role of silicon in wheat against stress conditions induced by drought, salinity or cadmium Ecotoxicol Environ Saf 2018 154 187 196 10.1016/j.ecoenv.2018.02.057 29475124 206. Schaller J Brackhage C Bäucker E Dudel EG UV-screening of grasses by plant silica layer? J Biosci 2013 38 413 416 10.1007/s12038-013-9303-1 23660676 207. Rizwan M Ali S Ibrahim M Farid M Adrees M Bharwana SA Zia-ur-Rehman M Qayyum MF Abbas F Mechanisms of silicon-mediated alleviation of drought and salt stress in plants: a review Environ Sci Pollu Res 2015 22 15416 15431 10.1007/s11356-015-5305-x 208. Zhu Z Wei G Li J Qian Q Yu J Silicon alleviates salt stress and increases antioxidant enzymes activity in leaves of salt-stressed cucumber (Cucumis sativus L.) Plant Sci 2004 167 527 533 10.1016/j.plantsci.2004.04.020 209. Massey FP Smith MJ Lambin X Hartley SE Are silica defences in grasses driving vole population cycles? Bioly Lett 2008 4 419 422 10.1098/rsbl.2008.0106 210. Massey FP Hartley SE Physical defences wear you down: progressive and irreversible impacts of silica on insect herbivores J Animal Ecol 2009 78 281 291 10.1111/j.1365-2656.2008.01472.x 211. Ning D Song A Fan F Li Z Liang Y Effects of slag-based silicon fertilizer on rice growth and brown-spot resistance Plosone 2014 9 e102681 10.1371/journal.pone.0102681 212. Schaller J Puppe D Kaczorek D Ellerbrock R Sommer M Silicon Cycling in Soils Revisited Plants 2021 10 2 295 33557192 213. Katz O Puppe D Kaczorek D Prakash NB Schaller J Silicon in the soil-plant continuum: intricate feedback mechanisms within ecosystems Plants 2021 10 4 652 10.3390/plants10040652 33808069 214. Pico LBO Zhang C Vyn TJ The central role of ear nitrogen uptake in maize endosperm cell and kernel weight determination during the lag period Field Crops Res 2021 273 108285 10.1016/j.fcr.2021.108285 215. Cassman KG Dobermann A Nitrogen and the future of agriculture: 20 years on Ambio 2022 51 17 24 10.1007/s13280-021-01526-w 33715091 216. Li C Wang X Guo Z Huang N Hou S He G Batchelor WD Siddique KH Wang Z Zhang D Optimizing nitrogen fertilizer inputs and plant populations for greener wheat production with high yields and high efficiency in dryland areas Field Crops Res 2022 276 108374 10.1016/j.fcr.2021.108374 217. Nayak HS Rice yield gaps and nitrogen-use efficiency in the Northwestern Indo-Gangetic Plains of India: Evidence based insights from heterogeneous farmers’ practices Field Crops Res 2022 275 108328 10.1016/j.fcr.2021.108328 218. Burke WJ Jayne TS Snapp SS Nitrogen efficiency by soil quality and management regimes on Malawi farms: Can fertilizer use remain profitable? World Develop 2022 152 105792 10.1016/j.worlddev.2021.105792 219. Min J Sun H Kronzucker HJ Wang Y Shi W Comprehensive assessment of the effects of nitrification inhibitor application on reactive nitrogen loss in intensive vegetable production systems Agri Ecosys Environ 2021 307 107227 10.1016/j.agee.2020.107227 220. Gou T Yang L Hu W Chen X Zhu Y Guo J Gong H Silicon improves the growth of cucumber under excess nitrate stress by enhancing nitrogen assimilation and chlorophyll synthesis Plant Physiol Bioch 2020 152 53 61 10.1016/j.plaphy.2020.04.031 221. Schaller J Brackhage C Gessner M Bäuker E Gert Dudel E Silicon supply modifies C: N: P stoichiometry and growth of Phragmites australis Plant Biol 2012 14 392 396 10.1111/j.1438-8677.2011.00537.x 22136652 222. Barreto RF Júnior AAS Maggio MA de Mello PR Silicon alleviates ammonium toxicity in cauliflower and in broccoli Scient Hort 2017 225 743 750 10.1016/j.scienta.2017.08.014 223. Cooke J Leishman MR Consistent alleviation of abiotic stress with silicon addition: a meta-analysis Func Ecol 2016 30 1340 1357 10.1111/1365-2435.12713 224. Pascual MB Echevarria V Gonzalo MJ Hernández-Apaolaza L Silicon addition to soybean (Glycine max L.) plants alleviate zinc deficiency Plant Physiol Biochem 2016 108 132 138 10.1016/j.plaphy.2016.07.008 27428367 225. Deus ACF de Mello PR de Cássia Félix Alvarez R, de Oliveira RLL, Felisberto G, Role of silicon and salicylic acid in the mitigation of nitrogen deficiency stress in rice plants SILICON 2020 12 997 1005 10.1007/s12633-019-00195-5 226. Mabagala F Geng Y Cao G Wang L Wang M Zhang M Effect of silicon on crop yield, and nitrogen use efficiency applied under straw return treatments Appl Ecol Environ Res 2020 18 5577 5590 10.15666/aeer/1804_55775590 227. Laîné P Haddad C Arkoun M Yvin J-C Etienne P Silicon promotes agronomic performance in Brassica napus cultivated under field conditions with two nitrogen fertilizer inputs Plants 2019 8 137 10.3390/plants8050137 31121992 228. Neu S Schaller J Dudel EG Silicon availability modifies nutrient use efficiency and content, C: N: P stoichiometry, and productivity of winter wheat (Triticum aestivum L.) Sci Rep 2017 7 1 8 10.1038/srep40829 28127051 229. Pál M Kovács V Szalai G Soós V Ma X Liu H Mei H Janda T Salicylic acid and abiotic stress responses in rice J Agron Crop Sci 2014 200 1 11 10.1111/jac.12037 230. Detmann KC Araújo WL Martins SC Sanglard LM Reis JV Detmann E Rodrigues FÁ Nunes-Nesi A Fernie AR DaMatta FM Silicon nutrition increases grain yield, which, in turn, exerts a feed-forward stimulation of photosynthetic rates via enhanced mesophyll conductance and alters primary metabolism in rice New Phytol 2012 196 752 762 10.1111/j.1469-8137.2012.04299.x 22994889 231. Soratto RP Fernandes AM Pilon C Souza MR Phosphorus and silicon effects on growth, yield, and phosphorus forms in potato plants J Plant Nutr 2019 42 218 233 10.1080/01904167.2018.1554072 232. Owino-Gerroh C Gascho G Effect of silicon on low pH soil phosphorus sorption and on uptake and growth of maize Commun Soil Sci Plant Anal 2005 35 2369 2378 10.1081/LCSS-200030686 233. Zhang Y Liang Y Zhao X Jin X Hou L Shi Y Ahammed GJ Silicon compensates phosphorus deficit-induced growth inhibition by improving photosynthetic capacity, antioxidant potential, and nutrient homeostasis in tomato Agron 2019 9 733 10.3390/agronomy9110733 234. Hu AY Xu SN Qin DN Li W Zhao XQ Role of silicon in mediating phosphorus imbalance in plants Plants 2020 10 51 10.3390/plants10010051 33383611 235. Schaller J, Puppe D, Kaczorek D, Ellerbrock R, Sommer M (2021) Silicon cycling in soils revisited. Plants 10: 295 236. Dunne EJ and Reddy K (2005) Phosphorus biogeochemistry of wetlands in agricultural watersheds. Nutrient management in agricultural watersheds: a wetland solution. Wageningen, The Netherlands: Wageningen Academic Publishers: 105–119 237. Xia Z He Y Yu L Lv R Korpelainen H Li C Sex-specific strategies of phosphorus (P) acquisition in Populus cathayana as affected by soil P availability and distribution New Phytol 2020 225 782 792 10.1111/nph.16170 31487045 238. Pavlovic J Kostic L Bosnic P Kirkby EA Nikolic M Interactions of silicon with essential and beneficial elements in plants Front Plant Sci 2021 12 1224 10.3389/fpls.2021.697592 239. Rajan S Phosphate adsorption and the displacement of structural silicon in an allophane clay J Soil Sci 1975 26 250 256 10.1111/j.1365-2389.1975.tb01949.x 240. Knorr K-H Lischeid G Blodau C Dynamics of redox processes in a minerotrophic fen exposed to a water table manipulation Geoderma 2009 153 379 392 10.1016/j.geoderma.2009.08.023 241. Schaller J Faucherre S Joss H Obst M Goeckede M Planer-Friedrich B Peiffer S Gilfedder B Elberling B Silicon increases the phosphorus availability of Arctic soils Sci Rep 2019 9 1 11 10.1038/s41598-018-37104-6 30626917 242. Sigg L Stumm W The interaction of anions and weak acids with the hydrous goethite (α-FeOOH) surface Colloids Surf 1981 2 101 117 10.1016/0166-6622(81)80001-7 243. Reithmaier G-MS Knorr K-H Arnhold S Planer-Friedrich B Schaller J Enhanced silicon availability leads to increased methane production, nutrient and toxicant mobility in peatlands Sci Rep 2017 7 1 8 10.1038/s41598-017-09130-3 28127051 244. Yang X Post WM Thornton PE Jain A The distribution of soil phosphorus for global biogeochemical modeling Biogeosci 2013 10 2525 2537 10.5194/bg-10-2525-2013 245. Dong Q Fang J Huang F Cai K Silicon amendment reduces soil Cd availability and Cd uptake of two Pennisetum species Int J Environ Res Public Health 2019 16 1624 10.3390/ijerph16091624 31075897 246. o Di Nasso NN, Angelini L, Bonari E, Influence of fertilisation and harvest time on fuel quality of giant reed (Arundo donax L.) in central Italy Eur J Agron 2010 32 219 227 10.1016/j.eja.2009.12.001 247. Hu AY Che J Shao JF Yokosho K Zhao XQ Shen RF Ma JF Silicon accumulated in the shoots results in down-regulation of phosphorus transporter gene expression and decrease of phosphorus uptake in rice Plant Soil 2018 423 317 325 10.1007/s11104-017-3512-6 248. Guo W Hou Y-L Wang S-G Zhu Y-G Effect of silicate on the growth and arsenate uptake by rice (Oryza sativa L.) seedlings in solution culture Plant Soil 2005 272 173 181 10.1007/s11104-004-4732-0 249. Kostic L Nikolic N Bosnic D Samardzic J Nikolic M Silicon increases phosphorus (P) uptake by wheat under low P acid soil conditions Plant Soil 2017 419 447 455 10.1007/s11104-017-3364-0 250. Chen J Zhang N-N Pan Q Lin X-Y Shangguan Z Zhang J-H Wei G-H Hydrogen sulphide alleviates iron deficiency by promoting iron availability and plant hormone levels in Glycine max seedlings BMC Plant Bol 2020 20 1 22 251. Dhankhar R, Gupta S, Gulati P (2022) Insights on plant–microbe interactions in soil in relation to iron dynamics. Vegetos: 1–18 252. Xing Y (2020), Universitäts-und Landesbibliothek Bonn. 253. Chowdhury NR Das R Joardar M Ghosh S Bhowmick S Roychowdhury T Arsenic accumulation in paddy plants at different phases of pre-monsoon cultivation Chemosphere 2018 210 987 997 10.1016/j.chemosphere.2018.07.041 30208559 254. Carrasco-Gil S Rodríguez-Menéndez S Fernández B Pereiro R de la Fuente V Hernandez-Apaolaza L Silicon induced Fe deficiency affects Fe, Mn, Cu and Zn distribution in rice (Oryza sativa L.) growth in calcareous conditions Plant Physiol Biochem 2018 125 153 163 10.1016/j.plaphy.2018.01.033 29453092 255. Martín-Esquinas A Hernández-Apaolaza L Rice responses to silicon addition at different Fe status and growth pH. Evaluation of ploidy changes Plant Physiol Biochem 2021 163 296 307 10.1016/j.plaphy.2021.04.012 33892228 256. Dauqan EM Abdullah A Medicinal and functional values of thyme (Thymus vulgaris L.) herb J Applied Biol Biotech 2017 5 017 022 257. Yang Z-X Yu S-Z Lin Y-C Zhang W-J Wang Y Wang R-G Xu S-X Yang T-Z Xue G Activation of potassium released from soil by root-secreted organic acids in different varieties of tobacco (Nicotiana tabacum) Funct Plant Biol 2020 47 318 326 10.1071/FP19137 32054564 258. Ahanger MA Tomar NS Tittal M Argal S Agarwal R Plant growth under water/salt stress: ROS production; antioxidants and significance of added potassium under such conditions Physiold Molecul Biol Plants 2017 23 731 744 10.1007/s12298-017-0462-7 259. Manishankar P Wang N Köster P Alatar AA Kudla J Calcium signaling during salt stress and in the regulation of ion homeostasis J Exp Bot 2018 69 4215 4226 10.1093/jxb/ery201 260. Garg N Bhandari P Silicon nutrition and mycorrhizal inoculations improve growth, nutrient status, K+/Na+ ratio and yield of Cicer arietinum L. genotypes under salinity stress Plant Growth Reg 2016 78 371 387 10.1007/s10725-015-0099-x 261. Thorne SJ Hartley SE Maathuis FJ Is silicon a panacea for alleviating drought and salt stress in crops? Front Plant Sci 2020 11 1221 10.3389/fpls.2020.01221 32973824 262. Yan G, Fan X, Zheng W, Gao Z, Yin C, Li T, Liang Y (2021) Silicon alleviates salt stress-induced potassium deficiency by promoting potassium uptake and translocation in rice (Oryza sativa L.). J Plant Physiol 258: 153379 263. Hajiboland R, Cherghvareh L, Dashtebani F (2017) Effect of silicon supplementation on wheat plants under salt stress. J Plant Process Fun 5 264. Adams WW, Stewart JJ, Polutchko SK, Demmig-Adams B (2018). In The Leaf: A Platform for Performing Photosynthesis. Leaf vasculature and the upper limit of photosynthesis. (Springer) pp. 27–54. 265. Daras G Rigas S Tsitsekian D Iacovides TA Hatzopoulos P Potassium transporter TRH1 subunits assemble regulating root-hair elongation autonomously from the cell fate determination pathway Plant Sci 2015 231 131 137 10.1016/j.plantsci.2014.11.017 25575998 266. Véry A-A Nieves-Cordones M Daly M Khan I Fizames C Sentenac H Molecular biology of K+ transport across the plant cell membrane: what do we learn from comparison between plant species? J Plant Physiol 2014 171 748 769 10.1016/j.jplph.2014.01.011 24666983 267. Barreto RF Maier BR de Mello PR de Morais TCB Felisberto G Silicon attenuates potassium and sulfur deficiency by increasing nutrient use efficiency in basil plants Sci Hortic 2022 291 110616 10.1016/j.scienta.2021.110616 268. Araújo WBS Teixeira GCM de Mello PR Rocha AMS Silicon mitigates nutritional stress of nitrogen, phosphorus, and calcium deficiency in two forages plants Sci Rep 2022 12 1 11 10.1038/s41598-022-10615-z 34992227 269. dos Santos Sarah MM de Mello PR de Souza Júnior JP Teixeira GCM dos Santos Duarte JC de Medeiros RLS Silicon supplied via foliar application and root to attenuate potassium deficiency in common bean plants Sci Rep 2021 11 1 13 33414495 270. Silva JLFd and Prado RdM (2021) Elucidating the action mechanisms of silicon in the mitigation of phosphorus deficiency and enhancement of its response in sorghum plants. J Plant Nut 44: 2572-2582 271. Sales AC Campos CNS de Souza Junior JP da Silva DL Oliveira KS de Mello PR Teodoro LPR Teodoro PE Silicon mitigates nutritional stress in quinoa (Chenopodium quinoa Willd.) Sci Rep 2021 11 1 16 10.1038/s41598-021-94287-1 33414495 272. Syed A Raza T Bhatti TT Eash NS Climate Impacts on the agricultural sector of Pakistan: Risks and solutions Environ Challenges 2022 6 100433 10.1016/j.envc.2021.100433 273. Khan KS. Qadir MF, Ahmad A, Naveed M, Raza T, Ditta A (2022). Efficacy of Different Endophytic Bacterial Strains in Enhancing Growth, Yield, and Physiological and Biochemical Attributes of Linum usitatissimum L. J Soil Sci Plant Nutr 1–12 274. Kim YH, Khan AL, Kim DH. Lee SY, Kim KM, Waqas, M, Jung HY, Shin JH, Kim JG, Lee, IJ (2014). Silicon mitigates heavy metal stress by regulating P-type heavy metal ATPases, Oryza sativa low silicon genes, and endogenous phytohormones. BMC Plant Biol 14: 1–13. 275. Schaller J Puppe D Heat improves silicon availability in mineral soils Geoderma 2021 386 114909 10.1016/j.geoderma.2020.114909 276. Guntzer F Keller C Poulton PR McGrath SP Meunier JD Long-Term removal of wheat straw decreases soil amorphous silica at Broadbalk, Rothamsted Plant Soil 2012 352 173 184 10.1007/s11104-011-0987-4 277. Klotzbüche T Treptow C Kaiser K Klotzbücher A Mikutta R Sorption competition with natural organic matter as mechanism controlling silicon mobility in soil Sci Rep 2020 10 11225 10.1038/s41598-020-68042-x 32641745
PMC009xxxxxx/PMC9885399.txt	==== Front J Math Teacher Educ Journal of Mathematics Teacher Education 1386-4416 1573-1820 Springer Netherlands Dordrecht 9569 10.1007/s10857-023-09569-4 Book Review Review of the book “Inquiry in university mathematics teaching and learning: the PLATINIUM project” http://orcid.org/0000-0002-6023-6029 Dorier Jean-Luc [email protected] grid.8591.5 0000 0001 2322 4988 Université de Genève, Geneva, Switzerland 30 1 2023 2023 26 4 567572 16 1 2023 © The Author(s), under exclusive licence to Springer Nature B.V. 2023 This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. issue-copyright-statement© Springer Nature B.V. 2023 ==== Body pmcThis book (Gómez-Chacón et al., 2022) is the result of the EU Erasmus + PLATINIUM project “Partnership for Learning And Teaching IN University Mathematics” for the development of Inquiry-Based Mathematics Education (IBME) in university education. It involved eight universities from seven European countries: the University of Agder in Kristiansand, Norway—the coordinator of the project—the University of Amsterdam in The Netherlands, Masaryk University and Brno University of Technology in the Czech Republic, Leibniz University Hannover in Germany, the Complutense University of Madrid in Spain, Loughborough University in the UK, and Borys Grinchenko Kyiv University in Ukraine. In over 300 very dense pages, it gives a precise idea of the very rich work achieved during the project. At the origin of this work is the observation that most sophomore students consider university courses very difficult, and several give up after a few weeks. Moreover, even those who pass the examinations successfully do not always achieve the teaching goals, in the sense that their comprehension is weak and their capacity to reinvest their learning very limited. Indeed, rote learning often dominates and little meaning is given to the concepts, which are only technically mastered. Usually, teachers blame students’ lack of investment or deficit in the prerequisites. In this book, the authors put aside such arguments and rather question the dominant teaching and evaluating practices to improve the situation. Their claim is that inquiry-based mathematics education (IBME) is a way to do this. Although this book is a major contribution to this issue, this state of the art dates back from at least the 1990s when, in most countries, many more students were able to enter university. For instance, in my own research on the teaching of linear algebra in the first year of university dating from the late 1980s (Dorier, 2000), I already pointed out:“However, the teaching of linear algebra is universally recognised as difficult. Students usually feel that they land on another planet; they are overwhelmed by the number of new definitions and the lack of connection with previous knowledge. On the other hand, teachers often feel frustrated and disarmed when faced with the inability of their students to cope with ideas that they consider so simple. Usually, they incriminate the lack of practice in basic logic and set theory or the impossibility for the students to use geometrical intuition. These complaints have a certain validity, but the few attempts at remedying this state of affairs—with the teaching of Cartesian geometry or/and logic and set theory prior to the linear algebra course—did not seem to improve the situation substantially.” (Dorier, 2002, p. 876) To overcome these difficulties, I developed a new type of teaching putting the question of meaning at the root of the problem. At this time, the term IBME was not used and such research works were not broadly known. Thanks to a general movement in different parts of the world, but especially in Europe with the Rocard report (Rocard et al., 2007), IBME has now become a very popular alternative to traditional teaching. Several projects and books have been devoted to IBME at the primary and secondary levels. One original feature of the PLATINIUM project is to investigate this issue at the tertiary level, including teachers’ education. Furthermore, this project makes some original contributions to the reflection on IBME, valid at all school levels, such as the original collaboration between mathematicians and mathematics educators and the number of examples provided. Based originally on John Dewey’s writings, the main idea behind IBME is to provide students with access to mathematical knowledge nearer to the way mathematicians and scientists work. This involves a less transmissive paradigm and more challenging tasks for students, but also more complex regulation by teachers. In principle, mathematicians teaching at university should be convinced of such ideas. However, we know that they usually claim that this takes too much time and is difficult to implement in day-to-day teaching. To tackle this issue, one of the originalities of PLATINIUM project is getting mathematicians and researchers in mathematics education work together in a very specific manner, as a community of inquiry as described by Jaworski (2019), according to the three-level model described in detail in Chap. 2. The authors are also keen to show practical outcomes from their theoretical assumptions.“Summarising, actions linked to teaching goals aim at learning goals, but these just cannot be ensured. Nevertheless, we believe that there are good reasons for teaching in terms of IBME. Diverse reasons and corresponding suggestions for the design of such teaching can be found in many places in this volume.” (Gómez-Chacón et al., 2022, p. 3) This quotation shows the great sense of honesty of the authors, characterizing an epistemological posture based on a good balance between theory and experimentation. The book starts with a chapter of introduction and is then divided in three parts of respectively three, five and nine chapters; it closes with a fourth part comprising the final chapter of conclusions and perspectives entitled “Lessons learned”. Part 1 presents the theoretical background and gives some essential clues on how the project has been conceived. Its three chapters are very interesting and full of essential keys to understanding the theoretical background and context of the entire research. Moreover, it is a great source of excellent documentation. Its title, “Inquiries communities in mathematics teaching and learning”, gives a good idea of the essential aspects of how the work was set up (Chap. 2). What is discussed in this chapter echoes several other European projects, in particular PRIMAS (https://primas-project.eu/), from which Katja Maass (the coordinator from the School of Education in Freiburg, Germany) and myself draw the entry on IBME in the Encyclopedia of Mathematics Education (Dorier and Maas, 2000). Moreover, several chapters in the book refer to some articles from the special issue of ZDM related to PRIMAS in particular, the contribution by Artigue and Blomhøj (2013). However, in PRIMAS the second Working Package (WP2) was devoted to the analysis of the national contexts of the 12 countries. The Geneva team had the reponsibility for WP2 in PRIMAS in close collaboration with the team in Spain, in charge of a connected WP. To account for the conditions and constraints favouring or hindering the implementation of IBME, we used the theoretical framework of Chevallard’s Anthropological Theory of Didactics. More precisely, we created a methodological tool based on the scale of levels of didactical co-determination (Bosch & Gascón, 2006, pp. 60–61) to analyse the various data found in official documents, curricula, textbooks, reports on classroom observations, and so on. The text we published in the special ZDM issue (Dorier & Garcia, 2013) presents this methodological tool in detail. In the PLATINIUM project of course the context is different since the countries are not quite the same and tertiary education is involved, while PRIMAS focused on primary and secondary. Yet, the tool could have been used to enrich the short analysis of the situation regarding IBME in the different countries of PLATINIUM presented in this book. Chapter 3 gives the presentation and reflection of an IBME-orientated tool developed in the project, the so-called “spidercharts”. This is a very interesting and original achievement by PLATINIUM. The conceptual model is made up of three nested levels or layers. The first two concern, on one hand, mathematics at play in the classroom (lectures, tutorials or other devices) and, on the other hand, the teaching processes, pedagogical and didactical choices and their effects. The third level regroups the entire developmental process in which participants reflect on practices in the other two layers and gather analysis and feedback data to inform practice and develop knowledge in practice. This tool supported the work of the communities of inquiry in both the production of resources and their analyses and in the professional development of their members. This is one of the most essential original aspects of this project and is extremely convincing and efficient. Chapter 4 presents a general model with identified needs in IBME-oriented teaching for students to consider. This is a very interesting approach and truly original, a very inspiring idea to show the importance of IBME for that kind of student, which makes it a good vector for inclusiveness! Indeed, the fact that in IBME the teacher and all students embark on an unknown trip enhances the initial conditions even more for everyone. The authors used the methodological framework of universal design to analyse how students with specific needs could be involved in all the pedagogical processes at stake in IBME. From these analyses, they developed a list of recommendations for a teacher to implement to guarantee equal participation of all students during inquiry activities. Even if these were initially intended for students with specific needs, they were also a great help for all. Part 2 focuses more concretely on the project as a whole. Chapter 5 gives many details about the origin of the project and building of the consortium. It also explains how the work was organised and the very original collaboration method in communities of inquiry. It is particularly interesting to see how it was adapted in the time of COVID-19, with all the necessary adjustments due to the pandemic and use of information and communications technology (ICT). Chapter 6 is devoted to the description of how the teaching units for student inquiry were created. It gives precious elements that can be used by any teacher interested in developing IBME in her or his class. This chapter starts with a discussion of the general frameworks used in PLATINIUM to design IBME activities, and then it gives the guiding design principles, documentation used, some examples, the way ICT was used and some specific information on the accessibility of teaching units for students with identified needs. Chapter 7 is devoted to the issue of professional development of lecturers when implementing IBME in teaching. This is a very interesting chapter based on the various experiences developed in the project on how workshops can be organised to help teachers (here lecturers) in developing their professional skills in IBME. It gives methods and materials as well as overall reflections that could inspire any group of teachers who want to improve collectively in IBME. Chapter 8 offers an interesting and useful reflection on the link between mathematical modelling and IBME. The fact that mathematicians with specific knowledge in other disciplines were associated with the project greatly supported the collaboration. Three examples of modelling tasks developed in the project are presented. Through one of the examples, the authors make a connection with the Realistic Mathematics Education (RME) developed by Freudenthal (1991) and quote Artigue and Blomhøj (2013): “in RME, modelling, and especially mathematisation, plays an essential role as a vehicle for the conceptual knowledge aimed at with no clear distinction being made between mathematisation of extra-mathematical situations and mathematisation within mathematics” (p. 805). With the other two examples they link mathematical modelling and IBME through the concept of active learning. They conclude on the three examples with another quotation from Artigue and Blomhøj (2013): “working with modelling in mathematics and in other subjects can thereby lead to valuable understanding of inquiry as a more general process with different particular realisations in different disciplines and contexts” (p. 805). Finally, Chap. 9 tackles the issue of evaluation of IBME and is related to one of the main intellectual outputs of the project entitled: “Guidelines and recommendations for quality assessment in inquiry-based learning environment” (IO6). The authors first present their theoretical background and research methodology, using the three-layer model of inquiry at the heart of the project. Then, they present four very different cases. The chapter includes the presentation of a cross-cases study aiming at finding some similar processes and outcomes in the IBME PLATINIUM approach. Part 3 is devoted to the presentation of the case studies developed at the eight universities involved in the project. Chapter 10 is an introduction to the eight following examples. It recalls the common theoretical and methodological grounds for all: the reference to didactics and pedagogies, the three-layer model, the community of inquiry, the work with students with identified needs and the use of ICT. In every case study, references to parts 1 and 2 are provided as a common framework. However, each gives specific examples of material for IBME tasks, and the whole is a huge resource for the reader. I cannot go into the details of the eight cases and will only give the headlines here, but all are worth reading in detail. Chapter 11 is an example of teaching differential equations for engineers developed at the University of Agder (Norway). Chapter 12 presents an experiment carried out at the University of Amsterdam (The Netherlands) to improve the mathematic literacy of biomedical students. Chapter 13 presents three different experiments made at the Masaryk University of Brno (Czech Republic). Chapter 14 is a study conducted by a group of mathematics educators involved in teacher education at the Hamburg and Hannover-Leibniz Universities (Germany). It is an interesting study on the professional growth of the group using the theoretical tools of PLATINIUM. Chapter 15 refers to several experiments at the Mathematics Education Centre at Loughborough University (UK) over the past 15 years in teaching both mathematics and mathematics education. Chapter 16 presents an experiment using IBME as a support to novice lecturers at the Complutense University of Madrid (Spain). Chapter 17 gives a report on the development of a local community of inquiry at the Brno University of Technology (Czech Republic). Finally, Chap. 18 presents an experience in implementing IBME at the Borys Grinchenko Kyiv University (Ukraine). In the introduction, the authors presenting part 3 claim:“Part 3 consists of eight case studies, each one presenting key elements of the activity and development of one partner group. Here we see diversity, both in terms of the starting points for each group, and also the developmental directions their activity and learning have taken.” “As you read this book, we hope you will enter into our activity, its modes of inquiry, and the issues we have addressed. For us, the new insights we have gained provide a rich basis for further activity in applying and understanding elements of inquiry-based progress in learning and teaching to provide, we hope, better learning experiences of mathematics for our students.” (Gómez-Chacón et al., 2022, p. 25) Indeed, the great variety of case studies supported by a common methodological and theoretical background is an incredible strength of this project. The short final Chap. 29, entitled “Epilogue”, forms part 4 of the book. In it, the authors compare the production of the book to a journey:“The journey has been a recurring metaphor in an attempt to illustrate the meaning of life. We find the term in the displacement from one territory to another, the walk that separates a departure from an arrival, as a space to give meaning to what has been lived. The metaphor of the journey thus becomes a commonplace worth analysing and so we wish to use it to synthesise the lessons learned from the production of this book. In the following paragraphs we will take a brief tour, like someone moving her finger to find herself on a map, to analyse this commonplace that we recognise as valuable for the university community in mathematics.” (Gómez-Chacón et al., 2022, p.351) The metaphor is nice and my journey as a reader of the book to write this report has been indeed very rich, inspiring and fruitful. Therefore, I can now recommend this book to everyone, whether researcher, math educator, mathematician or mathematics teacher. It will certainly become a reference not only for those interested in university teaching and IBME, but also more generally as a model of a very inspiring investigation for the whole mathematics education community. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Artigue M Blomhøj M Conceptualizing inquiry-based education in mathematics ZDM the International Journal on Mathematics Education 2013 45 6 797 810 10.1007/s11858-013-0506-6 Bosch M Gascón J Twenty-five years of the didactic transposition ICMI Bulletin 2006 58 51 63 Dorier, J. -L. (2002). Teaching linear algebra at university. In L. Tatsien (ed.), Proceedings of the international congress of mathematicians, Beijing 2002, August 20–28, (Vol. III-Invited Lectures, pp. 875–884). Beijing: Higher Education Press. https://www.mathunion.org/icm/proceedings. Dorier J-L On the teaching of linear algebra 2000 Kluwer Academic Publisher Dorier J-L Garcia FJ Challenges and opportunities for the implementation of inquiry-based learning in day-to-day teaching ZDM the International Journal on Mathematics Education 2013 45 6 837 849 10.1007/s11858-013-0512-8 Dorier J-L Maass K Lerman S Inquiry based mathematics education Encyclopedia of mathematics education 2020 Springer 384 388 Freudenthal H Revisiting mathematics education 1991 Kluwer Academic Publishers Gómez-Chacón I Hochmuth R Jaworski B Rebenda J Ruge J Thomas S Inquiry in university mathematics teaching and learning—the PLATINUM project 2022 Masaryk University Press Jaworski B Potari D Chapman O Inquiry-based practice in university mathematics teaching development International handbook of mathematics teacher education: Vol. 1. Knowledge, beliefs, and identity in mathematics teaching and teaching development 2019 Koninklijke Brill/Sense Publishers 275 302 Rocard, M., Cesrmley, P., Jorde, D., Lenzen, D., Walberg-Herniksson, H., & Hemmo, V. (2007). Science education. NOW: a new pedagogy for the future of Europe. Brussels, Belgium: Office for Official Publications of the European Communities. www.eesc.europa.eu/en/documents/rocard-report-science-education-now-new-pedagogy-future-europe.
PMC009xxxxxx/PMC9898691.txt	==== Front Sci China Life Sci Sci China Life Sci Science China. Life Sciences 1674-7305 1869-1889 Science China Press Beijing 36738432 2225 10.1007/s11427-022-2225-3 Research Paper Herbal small RNAs in patients with COVID-19 linked to reduced DEG expression Qiao Xiangyu 1 Huang Fengming 1 Shi Xiaohu 2 Deng Xingyu 1 Zhang Cong 13 Mei Song 1 Wang Zhiqing 1 Zhou Congzhao 3 Jiang Chengyu [email protected] 1 Tan Xinghua [email protected] 4 1 grid.506261.6 0000 0001 0706 7839 State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Department of Biochemistry, School of Basic Medicine Peking Union Medical College, Beijing, 100005 China 2 grid.506261.6 0000 0001 0706 7839 Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730 China 3 grid.59053.3a 0000000121679639 Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, 230027 China 4 grid.410737.6 0000 0000 8653 1072 Guangzhou Eighth People’s Hospital, Guangzhou Medical University, Guangzhou, 510440 China 3 2 2023 2023 66 6 12801289 27 7 2022 16 10 2022 © Science China Press 2023 This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. In China, more than 80% of patients with coronavirus disease 2019 (COVID-19) received traditional Chinese medicine (TCM) as a treatment and their clinical efficacy have been reported. However, the underlying molecular mechanism remains unclear. Previous studies have identified herbal small RNAs (sRNAs) as novel functional components. In this study, a cohort of 22 patients with COVID-19 treated with Toujie Quwen (TQ) granules was analyzed. We observed thousands of herbal small RNAs that entered the blood cells of patients after the consumption of TQ granules. In response to this treatment, the reduced differentially expressed genes (DEGs) were highly correlated with the predicted target genes of the most prevalent herbal sRNAs detected in the blood. Moreover, the predicted target genes of the top 30 sRNAs from each of the 245 TCMs in the Bencao sRNA Atlas overlapped with 337 upregulated DEGs in patients with mild COVID-19, and 33 TCMs, with more than 50% overlapping genes were identified as effective TCMs. These predicted target genes of top 30 sRNAs from Juhong, Gualoupi and Foshou were confirmed experimentally. Our results not only elucidated a novel molecular mechanism of TCM potential clinical efficacy for COVID-19 patients, but also provided 33 effective COVID-19 TCMs for prescription optimization. Supporting Information The supporting information is available online at 10.1007/s11427-022-2225-3. The supporting materials are published as submitted, without typesetting or editing. The responsibility for scientific accuracy and content remains entirely with the authors. traditional Chinese medicine Toujie Quwen granules COVID-19 transcriptome issue-copyright-statement© Science China Press 2023 ==== Body pmcElectronic Supplementary Material Herbal small RNAs in patients with COVID-19 linked to reduced DEG expression Acknowledgements This work was supported by the National Natural Science Foundation of China (81788101, 32100104), the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (2021-I2M-1-022), the CAMS Endowment Fund (2021-CAMS-JZ001) and the Overseas Expertise Introduction Center for Discipline Innovation (“111 Center”) (BP0820029) and the National Science and Technology Major Project (2018ZX10102-001-005-002). Compliance and ethics The author(s) declare that they have no conflict of interest. Contributed equally to this work ==== Refs References Cao, Y., Lin, Y., Sun, N., Du, X., Dong, Y., Mei, S., Deng, X., Li, X., Guo, S., Tang, K., et al. (2022). A comprehensive analysis of the Bencao (herbal) small RNA Atlas reveals novel RNA therapeutics for treating human diseases. Sci China Life Sci. Accepted. Chinese, Pharmacopoeia. Commission Pharmacopoeia of the People’s Republic of China 2015 Beijing China Medical Science Press Du J Liang Z Xu J Zhao Y Li X Zhang Y Zhao D Chen R Liu Y Joshi T Plant-derived phosphocholine facilitates cellular uptake of anti-pulmonary fibrotic HJT-sRNA-m7 Sci China Life Sci 2019 62 309 320 10.1007/s11427-017-9026-7 28378154 Fu, X., Lin, L., Tan, X. (2020). Clinical study on treatment of cases of COVID-19 with Toujie Quwen Granules. Chinese J Exp Trad Med Formul, 10.13422/j.cnki.syfjx.20201314. Furtado RHM Berwanger O Fonseca HA Corrêa TD Ferraz LR Lapa MG Zampieri FG Veiga VC Azevedo LCP Rosa RG Azithromycin in addition to standard of care versus standard of care alone in the treatment of patients admitted to the hospital with severe COVID-19 in Brazil (COALITION II): a randomised clinical trial Lancet 2020 396 959 967 10.1016/S0140-6736(20)31862-6 32896292 Horby P Mafham M Linsell L Bell JL Staplin N Emberson JR Wiselka M Ustianowski A Elmahi E Prudon B Effect of hydroxychloroquine in hospitalized patients with COVID-19 N Engl J Med 2020 383 2030 2040 10.1056/NEJMoa2022926 33031652 Houston BL Lawler PR Goligher EC Farkouh ME Bradbury C Carrier M Dzavik V Fergusson DA Fowler RA Galanaud JP Anti-thrombotic therapy to ameliorate complications of COVID-19 (ATTACC): study design and methodology for an international, adaptive Bayesian randomized controlled trial Clin Trials 2020 17 491 500 10.1177/1740774520943846 32815416 Hu B Guo H Zhou P Shi ZL Characteristics of SARS-CoV-2 and COVID-19 Nat Rev Microbiol 2021 19 141 154 10.1038/s41579-020-00459-7 33024307 Huang F Du J Liang Z Xu Z Xu J Zhao Y Lin Y Mei S He Q Zhu J Large-scale analysis of small RNAs derived from traditional Chinese herbs in human tissues Sci China Life Sci 2019 62 321 332 10.1007/s11427-018-9323-5 30238279 Ji C Kriaucionis S Kessler BM Jiang C From herbal small RNAs to one medicine Sci China Life Sci 2019 62 285 287 10.1007/s11427-019-9513-y 30863963 Lee DYW Li QY Liu J Efferth T Traditional Chinese herbal medicine at the forefront battle against COVID-19: clinical experience and scientific basis Phytomedicine 2021 80 153337 10.1016/j.phymed.2020.153337 33221457 Li X Liang Z Du J Wang Z Mei S Li Z Zhao Y Zhao D Ma Y Ye J Herbal decoctosome is a novel form of medicine Sci China Life Sci 2019 62 333 348 10.1007/s11427-018-9508-0 30900166 Liang J Mei S Qiao X Pan W Zhao Y Shi S Zhai Y Wen H Wu G Jiang C A botanical medicine dragon’s blood exhibited clinical antithrombosis efficacy similar to low molecular weight heparin Sci China Life Sci 2021 64 1691 1701 10.1007/s11427-020-1848-8 33521854 Luo H Yang M Tang QL Hu XY Willcox ML Liu JP Characteristics of registered clinical trials on Traditional Chinese Medicine for coronavirus disease 2019 (COVID-19): A scoping review Eur J Integrative Med 2021 41 101251 10.1016/j.eujim.2020.101251 Nojomi M Yassin Z Keyvani H Makiani MJ Roham M Laali A Dehghan N Navaei M Ranjbar M Effect of Arbidol (Umifenovir) on COVID-19: a randomized controlled trial BMC Infect Dis 2020 20 954 10.1186/s12879-020-05698-w 33317461 Sun CY Sun YL Li XM The role of Chinese medicine in COVID-19 pneumonia: a systematic review and meta-analysis Am J Emergency Med 2020 38 2153 2159 10.1016/j.ajem.2020.06.069 Wang WY Xie Y Zhou H Liu L Contribution of Traditional Chinese Medicine to the treatment of COVID-19 Phytomedicine 2021 85 153279 10.1016/j.phymed.2020.153279 32675044 Wang Y Zhang D Du G Du R Zhao J Jin Y Fu S Gao L Cheng Z Lu Q Remdesivir in adults with severe COVID-19: a randomised, double-blind, placebo-controlled, multicentre trial Lancet 2020 395 1569 1578 10.1016/S0140-6736(20)31022-9 32423584 Yang Y Islam MS Wang J Li Y Chen X Traditional Chinese Medicine in the treatment of patients infected with 2019-new coronavirus (SARS-CoV-2): a review and perspective Int J Biol Sci 2020 16 1708 1717 10.7150/ijbs.45538 32226288 Zhang C Zhang B RNA therapeutics: updates and future potential Sci China Life Sci 2023 66 12 30 10.1007/s11427-022-2171-2 36100838 Zhang L Hou D Chen X Li D Zhu L Zhang Y Li J Bian Z Liang X Cai X Exogenous plant MIR168a specifically targets mammalian LDLRAP1: evidence of cross-kingdom regulation by microRNA Cell Res 2012 22 107 126 10.1038/cr.2011.158 21931358 Zhao Z Li Y Zhou L Zhou X Xie B Zhang W Sun J Prevention and treatment of COVID-19 using Traditional Chinese Medicine: A review Phytomedicine 2021 85 153308 10.1016/j.phymed.2020.153308 32843234 Zhou LK Zhou Z Jiang XM Zheng Y Chen X Fu Z Xiao G Zhang CY Zhang LK Yi Y Absorbed plant MIR2911 in honeysuckle decoction inhibits SARS-CoV-2 replication and accelerates the negative conversion of infected patients Cell Discov 2020 6 54 10.1038/s41421-020-00197-3 32802404 Zhou Z Zhou Y Jiang XM Wang Y Chen X Xiao G Zhang CY Yi Y Zhang LK Li L Decreased HD-MIR2911 absorption in human subjects with the SIDT1 polymorphism fails to inhibit SARS-CoV-2 replication Cell Discov 2020 6 63 10.1038/s41421-020-00206-5 32934821 Zhu N Zhang D Wang W Li X Yang B Song J Zhao X Huang B Shi W Lu R A novel coronavirus from patients with pneumonia in China, 2019 N Engl J Med 2020 382 727 733 10.1056/NEJMoa2001017 31978945
PMC009xxxxxx/PMC9901385.txt	==== Front Inf Syst E-Bus Manage Information Systems and e-Business Management 1617-9846 1617-9854 Springer Berlin Heidelberg Berlin/Heidelberg 615 10.1007/s10257-022-00615-x Original Article A new method for solving the mobile payment scheduling problem using harris hawks optimization algorithm during the COVID-19 pandemic Sun Wen 1 She Chen 2 Khalilzadeh Mohammad [email protected] 34 Mao Hui-Zhen 5 Xu Yi-Peng [email protected] [email protected] 6 1 grid.12981.33 0000 0001 2360 039X School of Business, Sun Yat-Sen University, No135 Xingangxi Road, Guangzhou, CN510275 People’s Republic of China 2 grid.410561.7 0000 0001 0169 5113 School of Economics and Management, Tiangong University, Tianjin, 300387 People’s Republic of China 3 grid.440592.e 0000 0001 2288 3308 CENTRUM Católica Graduate Business School, Lima, 15023 Peru 4 grid.440592.e 0000 0001 2288 3308 Pontificia Universidad Católica del Perú, Lima, 15023 Peru 5 grid.443347.3 0000 0004 1761 2353 School of Accounting, Southwestern University of Finance and Economics, Sichuan, 610000 People’s Republic of China 6 grid.410561.7 0000 0001 0169 5113 School of Mathematical Sciences, Tiangong University, Tianjin, 300387 People’s Republic of China 6 2 2023 121 4 11 2021 7 4 2022 6 5 2022 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023, corrected publication 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. The Coronavirus Disease 2019 (COVID-19) epidemic is causing once-in-a-century upheavals in global civilization. Payment systems have advanced lately, from simple cash or credit card transactions to various forms of mobile payment systems. This transformation is occurred due to COVID 19 and shifts in the economy, the growth of social networks, technical advancements on the Internet, and the increased usage of mobile devices. Throughout COVID19, this article offers a unique approach to the payment scheduling issue, which seeks out a timetable that enhances the project's stakeholders' benefit. Both the sponsor and the contractor in a project want to have a strong payment plan on their own. To create an equal schedule between the sponsor and the development team, the timing of payments and the completion periods of project activities are decided concurrently. The Harris hawks optimization method is designed to tackle the problem because of its high NP-hardness. Harris hawks optimization is a novel meta-heuristic nature-inspired optimizer inspired by how Harris hawks hunt food in nature. By comparing the suggested Harris hawks optimization optimizer to existing nature-inspired methods, the efficacy of the suggested Harris hawks optimization optimizer is determined. The Harris hawks optimization algorithm appears to be highly promising based on the statistical findings and comparisons. The MATLAB simulator's simulation findings confirm the algorithm's superiority over earlier efforts regarding energy, cost, delay time, and net value. Keywords Mobile Payment Scheduling Harris Hawks Optimization Algorithm COVID-19 Pandemic ==== Body pmcIntroduction Every day, more electronic gadgets are developed in response to the rising community and ever-expanding technology (Shokouhyar et al. 2021). Any financial transaction via the Internet is referred to as e-commerce (Zhao et al. 2021a). The payer utilizes his credit card to complete the transaction in most cases. For safe transaction completion, an e-commerce transaction requires the buyer or cardholder, the buyer's credit card issuer (bank), the merchant, the certifying authority, and the merchant's acquirer (bank). For creating a secure link among the engaged parties, the majority of these protocols use a key agreement mechanism (Vahidalizadehdizaj and Leider 2017). Mobile smart devices (like laptops or smartphones) are commonly utilized in routine life due to the advancement and pervasiveness of mobile communication technology (Afroz et al. 2020). As a result, there is a growing need for diverse Internet services (Chen et al. 2019). Currently, mobile payment is an extensively employed technique for businesses and financial institutions to deliver payment services through mobile devices like smartphones and iPads (Liao et al. 2018). Any transaction carried out through mobile devices, including the direct or indirect exchange of financial values among parties, is called mobile payment. The fact that a mobile phone may be utilized as a payment device in diverse scenarios is an intriguing element of mobile payment. Optimists predict that mobile devices will shift from a basic communication device to a payment techniques in the future world economy (Dizaj et al. 2011). Due to a considerable drop in the physical use of credit cards, cash, and debit cards throughout the COVID-19 epidemic, an increasing percentage of mobile payments are used (Cao 2021; Vahdat 2021). According to a recent study, privacy, security, and ease of use are the three criteria for mobile payment subscribers, making mobile payment security an inescapable challenge in the growth of mobile payment businesses (Zhang et al. 2016). The Project Payment Scheduling Problem (PPSP), which is a novel branch of the Max-net Present Value (NPV) project scheduling issue, is concerned with how to plan progress payments to increase the contractor's or client's NPV (He et al. 2014). A schedule is a plan for conducting a method or operation that includes a list of the activities and times. Scheduling problems in project management, which is considered one of the most important and challenging aspects, have caught much of the attention of theoreticians and practitioners in the research community. It is a generic name given to a whole class of issues. The allocation of the project resources, optimizing the project duration, and estimated costs are necessary (Trinh et al. 2019). Because of the restrictions inherent in the project, project scheduling entails establishing the start time of each project activity and developing a timing sequence to conduct a set of relevant tasks in order of their priority (He, Liu et al. 2009). Hence, there is a balance between project completion time and overall cost, and one or more aims are met. The alternatives are evaluated in order to fulfill these goals, and then the best option is chosen (Hegazy and Petzold 2003). There are priority restrictions among tasks in all projects, but additional limitations, such as resource restrictions, exist. Resources are allocated according to the requirements of the operations, the time it takes to complete them, and the financial flows employed in the building process (Seyfi Sariqaya et al. 2019; Zhao et al. 2021a, b). COVID-19's outbreak and subsequent management measures have resulted in a worldwide medical disaster that has impacted all facets of life. Policymakers and directors of companies or organizations that employ mobile payments should begin strategizing to resolve the COVID-19 epidemic's future challenges. Because the mobile payment-scheduling issue is NP-hard, numerous meta-heuristic and heuristic processes have been constructed to tackle it throughout the COVID-19 epidemic. Earlier research has employed Harris' Hawks Optimization (HHO) approach to handle various issues and demonstrated that it outperforms other newly invented and popular optimization techniques (Elgamal et al. 2020). We were inspired to use HHO to solve challenges with mobile payment scheduling. As far as we know, investigating the HHO for solving this issue was not done, especially in COVID 19 era; therefore, this is the main innovation of the article. HHO is based on the coordinated behavior and chase method of Harris' hawks in nature, known as surprise pounce. Multiple hawks work together to attack a victim from various directions to catch it off guard. According to the dynamic nature of circumstances and the prey's fleeing tactics, Harris hawks can exhibit diverse pursuing patterns (Heidari et al. 2019). This investigation statistically models such dynamic behaviors and patterns to develop an optimization strategy. We are trying to solve the related problems as follows:RQ1: Has the HHO algorithm minimized delay time in mobile payment scheduling during the COVID-19 epidemic? RQ2: Has the HHO algorithm minimized energy utilization in mobile payment scheduling during the COVID-19 epidemic? RQ3: Has the HHO algorithm minimized the cost of mobile payment scheduling during the COVID-19 epidemic? RQ4: Has the HHO algorithm maximized the NPV of the mobile payment schedule during the COVID-19 epidemic? There are five sections to this study. The first section introduces mobile payment and its issues. A variety of strategies are explored and contrasted in Sect. 2. The approach proposed in this study is then explained in Sect. 3. Section 4 contains information on the recommended technique's simulation, data sets, and assessment criteria, among other things. Section 5 describes the limitation, implications, and future work. The paper's accomplishments and potential study topics are presented in Sect. 6. Finally, Appendix A contains a list of notations utilized in this study (Table). Related work Because of improvements in digital technology, m-payment mechanisms have gotten a lot of focus in the last ten years. These procedures can greatly enhance the quality of online services if they are used in the internet industry (Thammarat and Techapanupreeda 2021). A summary of some optimization algorithms employed in mobile payment problems is presented below. Mukhopadhyay and Upadhyay (2022) examined how organizational involvement and platform competition affected platform-based payment service uptake and retention intentions. The study was backed by a small number of conversations and is dependent on archive data. The findings revealed that organizational interventions (in various ways) boosted people's willingness to adopt m-payment. Furthermore, competition among numerous payment systems had a beneficial influence on customers' intentions to continue using m-payments. Dhamija and Dhamija (2022) proposed architecture and presented a security approach for mobile payments systems. The proposed architecture defined the role and responsibilities of each participating entity and took care of all the concerning issues in the mobile payment system. A multi-factor authorization security approach based on hashing and cryptography had been adopted, adding an extra security layer before the transaction got executed, generating a unique OTP. The results showed that the proposed approach is implemented as a Web application and validated through experimentation. Chen et al. (2021) suggested an antagonistic network for bias correction. They employed a limited collection of unbiased data collected by a full-randomized assignment approach to developing an unbiased framework, which they then utilized to remove bias using adversarial learning. According to the findings, their solution beats state-of-the-art alternatives and increases the performance of the resultant allotment policy in a real-time marketing campaign. Zhang et al. (2020) looked at the Payment Scheduling Negotiation Problem (PSNP), which is a realistic expansion of the Resource-Constrained Project Scheduling Problem (RCPSP). It takes into account both the contractor's and the customer's needs. These two parties negotiated to develop an activity schedule and a payment project plan to enhance NPVs on both sides and create a win–win outcome. They presented a strategy that included the following aspects. First, the issue was recast as a preference-based bi-objective optimization issue. Second, a multilayer area interest method was given to handle the customer and contractor's differing priorities. Third, to address the PSNP effectively, this method was integrated into the Nondominated Sorting Genetic Algorithm II (NSGA-II). According to the observations, the suggested approach could search the Region of Interest (ROI) and provide more pleasing results. Also, Vahdani and Shams (2020) looked at a multi-mode capital-restricted PPSP with a bonus-penalty structure applied at the project's deadline. They created a mathematical model of the issue based on the project's event-based description. They ran a computing trial to see how well our technique fared against the Simulated Annealing (SA) algorithm and two heuristic methods, Random Sampling (RS) and Multi-Start Iterative Improvement (MSII). The findings revealed that Tabu Search (TS) is a significantly more powerful solution approach, particularly for big issue cases. They also looked at the impact of important issue factors on the contractor's NPV. They discovered that the number of payments, the contractor's initial capital liquidity, and the awarding ratio of the bonus-penalty construction are positively related to the NPV. Furthermore, Gholizadeh (2018) studied the multi-mode project scheduling issue aiming to plan payments considering limited resources. This model tried to propose a possibly close to reality schedule by taking realistic assumptions into account. Renewable resources (such as machinery, workforce, and equipment) and non-renewable ones (such as money and consumption) were considered in this model. Then, the issues of scheduling and planning the project payment were examined using the objectives of increasing the NPV of the project and decreasing the project's completion time. They subsequently recommended the NSGA-II method to deal with the issue in huge dimensions. The observations demonstrated that the recommended technique outperformed other approaches. Moreover, Li et al. (2017) used the NPV of discounted cash flows to assess the potential value of multi-mode and resource constraints (MRCPSNP). They used a co-evolution method to mimic the negotiation procedure, in which the two sides negotiate to maximize their respective NPV. A Multi-swarm Particle Swarm Optimization (MPSO) technique combines the co-evolution approach and the multi-level region of interest methodology into a PSO algorithm. The recommended technique was extremely successful and promising compared to the outcomes of 30 project examples. Finally, Mortazavi Nejad et al. (2017) tackled a project payment schedule where a project deadline was set and operations were permitted to be compressed to maximize the contractor's NPV. The volume of work completed at so-called review points was determined using two distinct techniques in this article. Only completed actions were evaluated in the first method. In the second method, any parts of the actions carried out were taken into account. The contractor might opt to crash some operations to maximize the volume of work completed at the review points, potentially increasing his NPV. A solution must have been reached because crashing action costs the contractor money. Two mathematical models were created to investigate each technique, assisting the contractor in making the best option possible. These models provided a method of determining if it is appropriate to halt particular activities and were useful. Even when the contractor paid for the activity crashing expenses, the contractor's NPV might be increased. Table 1 examines and contrasts the available approaches for the issue of m-payment scheduling and the benefits and drawbacks of each solution. To solve these problems, the mobile payment scheduling problem using Harris hawks optimization algorithm during the COVID-19 is proposed, followed by the decreased cost, energy, delay time, and improved net present value.Table 1 Comparison of available methods Article Purpose Method Outputs Weaknesses Mukhopadhyay and Upadhyay (2022) Examining the impact of institutional intervention and platform competition on the initial adoption and continuance intention of platform-based payment services Drawing insights from the institutional theory and theories on the multisided platform Using archival data and a limited number of interviews Understanding of the technology adoption challenges Highlighting the relative success of technology adoption Improving the continuance intention of users to use mobile payments Using the limited data Dhamija and Dhamija (2022) Defining the role and responsibilities of each participating entity and taking care of all the concerning issues in the mobile payment system Preparing architecture and presenting a security approach for mobile payments systems Increasing security Improving network availability and bandwidth Not considering cost Chen et al. (2021) Introducing the mechanism of adversarial learning to build an unbiased response model Presenting an adversarial learning method for incentive optimization in mobile payment marketing Improving allocation Reducing accuracy Not considering energy consumption Zhang et al. (2020) Looking at the PSNP, which is a realistic expansion of the RCPSP Proposing a multi-level ROI strategy to deal with the complicated preferences in the PSNP Controlling the tolerance degree of the preferences Improving NPVs Not considering user preferences Gholizadeh and AFSHAR (2018) Studying the multi-mode project scheduling issue aiming to plan payments Proposing the NSGA-II algorithm Increasing the NPV of the project Decreasing the completion time of the project Considering limited resources Li et al. (2017) Providing MRCPSNP for the practical extension to the RCPSP Forming an MPSO approach Increasing the NPV of the project Not considering delay time Mortazavi Nejad et al. (2017) Payment scheduling under project crashing based on project progress Using two different approaches to determine the volume of work performed (review points) Developing two mathematical models Increasing the NPV Improving activity crashing costs Not considering energy consumption Increasing complexity Harris Hawks meta-heuristic optimization algorithm The HHO algorithm is a population-based meta-heuristic method. It is inspired by the life of hawks in nature and the way they hunt (Kolli and Tatavarthi 2020). This algorithm was introduced by Heidari et al. (2019) Harris hawks seek prey by working together in the wild. Their predation is mostly based on unexpected attacks. In addition, the hawks can employ diverse pursuing techniques in response to the changing features of the environment and prey escape tendencies. Exploitation, exploration, and the change of those two states will be used to define the algorithm in HHO. Figure 1 illustrates the fundamental logic of HHO.Fig. 1 The logic of HHO (Jiao et al. 2020) Three stages make up the HHO algorithm: 1. Exploration phase, 2.1 The transition from exploration to exploitation (extraction), 3. Exploitation phase (extraction): soft siege and hard siege. Exploration phase Hawks can detect prey with their keen eyes without being seen by prey. For successful hunting, they spend several hours monitoring their prey and attacking at the right time. In this algorithm, the answer candidates are hawks, and the best hawk (answer) is introduced as a hunting candidate (leader); it may be the main optimal answer in its neighborhood. The placement of the hawks in the exploration phase is done in two strategies. Strategy 1: They choose their posture depending on the positions of other individuals of their family and prey (q < 0.5). Strategy 2: Hawks are randomly scattered in random positions within the search space (q ≤ 0.5). In the following stage, the hawks' position vector will be computed as follows:1 Xt+1=Xrandt-r1Xrandt-2r2Xtq≥0.5Xrabitt-Xmt-r3LB+r4VB-LBq<0.5 where, Xrand(t), Xrabit(t), Xm(t), LB, and VB indicate the random selection of hawks in the community, the mean location of the present community of hawks, the hunting location (rabbit), the vector position of the current position of hawks, the lower limit, and the upper limit, respectively. Parameters r1, r2, r3, r4, and q are randomly selected numbers between (0, 1) intervals, updated at each step. The preceding formula is used to calculate the estimates of the mean location of the present group of hawks in this formula:2 Xmt=1N∑i=1NXit In this regard, N and Xi(t) represent the population of hawks and the position of each hawk in stage t. Transitioning from the exploration stage to the extraction stage: This algorithm is capable of transitioning from exploring to extracting. It may adjust its behavior depending on how much energy the victim has left. Throughout the run, the energy of the prey is depleted. Equation 3 is used to calculate the energy of the prey:3 E=2E01-tT where, E0 and T represent the initial energy and the highest number of steps, two states can occur here:E≥1: In this case, the hawks are looking for different areas to find the hunting place, so the exploration phase must be updated and re-executed. E<1: In this case, the algorithm tries to find the best answer to check in its neighborhood so that the algorithm will move to the extraction phase. Extraction phase Here, the hawks should perform the sudden attack stage by the candidate prey appointed in the previous stage. As stated, this phase has two modes of soft and hard siege. Parameter E, or hunting escape energy, determines which state we are in.A. Soft siege: When the prey has enough energy to escape, the hawks gently surround it to deplete its energy (E≥0.5). The accompanying formula can be used to update the hawks' location at this point:4 Xt+1=ΔXt-EJXrabitt-Xt where,5 ΔXt=Xrabitt-Xt 6 J=21-r5 Here, the variation across the position vector of food and the present location is represented by ∆X(t), J, r5, a random value between 1 and 0, imitating the hunting motion. When the rabbit has sufficient strength to flee throughout the soft siege, the hawks make multiple fast team dives around the victim. They attempt to slowly alter their position and course in response to the prey's deceptive moves. The accompanying formula can be used to provide an update on the location of the hawks:7 Xt+1=YifFY<FXtZifFZ<FXt where8 Y=Xrabbitt-EXrabbitt-Xt 9 Z=Y+S∗LFD 10 LFD=0.01∗u∗σϑ1β 11 σ=r1+β∗sinπβ2r1+β2∗β∗2β-121β where, u, S, D, ϑ, and β represent the random value between 1 and 1, the random vector with 1*D size, the dimensions of the problem, the random value between 1 and 0, and the constant parameter with the value of 1.5, respectively. LF(D) is defined to simulate the deceptive movements of prey during the escape phase. Hawks are constantly changing positions to deal with all kinds of deceptive movements of prey. Therefore, according to these behaviors, they can choose the best way to reach the prey.B. Hard siege: When the prey loses its energy, the hawks tighten the siege. The hawks' new location is calculated using the corresponding formula:12 Xt+1=Xrabbitt-EΔXt When the siege is challenging and the victim lacks the strength to run, the hawks strive to shorten the gap between themselves and the running prey. The accompanying formula is used to compute the new location of the hawks in this scenario (Wang et al. 2021):13 Xt+1=YifFY<FXtZifFZ<FXt 14 Y=Xrabbitt-EJXrabitt-Xmt 15 Z=Y+S∗LFD The flowchart of HHO is displayed in Fig. 2.Fig. 2 HHO algorithm flowchart The pseudo-code for the algorithm is given below (Milenković 2021): Results Math Works, Inc. of Natick, Massachusetts, is very economical and designed, which also provides support. MATLAB is an efficient programming platform for meta-heuristic algorithms like HHO, and it offers several benefits over other platforms, including:Its major data component is the matrix; It has a strong capacity to study the impact of various physical layer factors on the device; It enables graphical outputting for generating data with a variety of techniques and capabilities; It has node creation freedom. Investigators may do sophisticated calculations and simulations with the help of MATLAB, and formerly accessible methods can be utilized as a novel toolbox (Sadrishojaei et al. 2021). MATLAB allows investigators to concentrate on their inventions instead of seeking the necessary computational resources. Thus, MATLAB is used to analyze the suggested approach. The suggested aggregation approach was simulated and evaluated using MATLAB software. A computer with Windows 7, an Intel Core i5 − 2.5 GHz processor, and 4 GB RAM is used for all the tests. Table 2 also includes the values of the technique's crucial parameters.Table 2 Values of parameters in HHO q, r1, r2, r3, r4, r5 U (0, 1) μ N (0, 1) v N (0, 1) β 1.5 F 6 Q 5 The objective function is displayed in the studied iterations to investigate the suggested algorithm's convergence. The outcomes reveal that the recommended method outperforms the GA (Seyfi Sariqaya et al. 2019) and Ant Colony Optimization (ACO) algorithm in terms of fitness. In 100 replications, the suggested strategy is compared against the GA and ACO to evaluate its convergence (Fig. 3).The delay time of mobile payment scheduling problem Fig. 3 Convergence diagram of three strategies in 100 iteration One direction to reduce delay time is to use new methods such as deep algorithms (Lv et al. 2021, Zhong et al. 2021) and unsupervised domain adaptation (Fang et al. 2020). This paper proposed an HHO algorithm to minimize the delay time in the mobile payment schedule. In Fig. 4, the suggested approaches' delay times are compared to ACO and GA. The suggested technique's latency reduced as the number of tasks increased, demonstrating that the recommended approach outperformed the other two techniques.The energy utilization of mobile payment scheduling problem Fig. 4 Comparison of the delay time of the proposed method to GA and ACO algorithms: (a) with ten tasks and (b) with 100 tasks Energy management is frequently considered a crucial aspect of developing nations' efforts to enhance their economic outlook (Ebrahimian et al. 2018). Numerous architectures and approaches for energy management systems are developed utilizing several optimization algorithms like the multi-objective PSO algorithm (Aghajani and Ghadimi 2018), Sine–Cosine Algorithm (SCA), and Crow Search Algorithm (CSA) (Yang et al. 2021). In order to reduce power usage in m-payment schedules, this article presented an HHO algorithm. Compared to ACO and GA, Fig. 5 demonstrates how much energy the suggested technique uses. As the tasks grow, the recommended technique's energy usage decreases compared to the other two, demonstrating that it performs well.The cost of the mobile payment scheduling problem Fig. 5 Comparison of energy utilization of the proposed method to the GA and ACO algorithms: (a) with ten tasks and (b) with 100 tasks Comparing the suggested method to ACO and GA, Fig. 6 displays the costs. Compared to the other two algorithms, the suggested technique's costs have dropped as the tasks have risen, indicating the recommended method's superior performance.Maximizing NPV Fig. 6 Comparing the costs of the recommended technique to the GA and ACO algorithms: (a) with ten tasks and (b) with 100 tasks When the financial analyst does not have total assurance in the values of cash flow characteristics, the choice will result in risk and uncertainty. In this scenario, the financial analysis must be based on the idea of "anticipated value". Rather than using an absolute number for the cash flow parameter, this approach uses a range of values depending on the pattern of previous data or potential volatility. Estimating the probability distribution of parameters and NPV and calculating the mean and variance of that distribution are effective in economic analysis. Risk is the result of variance in the value of variables that can be used to predict the behavior of changes in values using random numbers. The expected value (estimated) in year K (Fk) has the mathematical expectation of E (Fk) and variance of Var (Fk). Therefore, the mathematical expectation of the E (NPV) and its variance (Var (NPV)) is calculated as follows:16 ENPV=∑K=0KPF,i%,K.EFk 17 VarNPV=∑K=0KPF,i%,K2.VarFk Volatility and uncertainty about the future cause the NPV or rate of return of a project to fluctuate widely. In such instances, the best socioeconomic choice is to approve a project with an average net present value (NPV) or a project with an average present value larger than 0 and above the average present value of other incompatible projects. Figure 7 shows the percentage change in NPV over time.Statistical analysis Fig. 7 Percentage of NPV changes over time Compared to the GA and ACO algorithms, an analytical method has been used to analyze the proposed method based on nonparametric statistical measures. Friedman is also utilized in several comparative investigations as a result of this characteristic. To conduct a quantitative analysis of the algorithms used to assess the investigation classifications, get the necessary post-hoc techniques, and calculate the regulated p values. For the randomly generalized implementation graphs, algorithms were statistically assessed.H1: The efficiency of the proposed method appears to be distinct from the other algorithms. H0: The efficiency of the proposed method does not appear to vary from the other algorithms. In terms of average ranks achieved by complete algorithms for 150 tasks, Tables 3 and 4 reflect Friedman's outcomes. We require to utilize the outcomes of Table 3 (Test statistics) to interpret the Friedman test outcomes to figure out if the discrepancy in the average success algorithms is important. According to the chi-square test (40.263), meaningful at an error rate of less than 0.01, the proposed method's result is analytically corrected with a 0.99 confidence level, as shown in this table. This result indicates that H0 is ruled out, and H1 is verified.Table 3 Test statistics Parameter Value N 200 Chi-square 40.263 df 2 Asymp. sig 0.000 a. Friedman Test Table 4 Friedman test (Ranks) Mean rank ACO 1.88 GA 1.96 Proposed method 2.04 We must now use the findings of Table 4 to determine which algorithm has the lowest and which method has the highest performance. According to this table, the average rankings of GA and ACO were 1.96 and 1.88, respectively. Nevertheless, the recommended technique's mean value is 2.04, indicating improved effectiveness. Limitation, implications, and future work The suggested approach, like other optimization methods, has some drawbacks. The main disadvantage is that it takes a long time to run compared to other algorithms. The mathematical complexity of the traditional HHO, not the recommended changes, explains the wasted time. Moreover, one of this method's limitations is considering four parameters in the mobile payment scheduling problem. In addition, HHO suffers from drawbacks of local optima and population diversity, so this method is other limitations. Utilizing the suggested strategy, the conclusions in this research will assist m-payment service suppliers in improving m-payment scheduling. Additionally, the outcomes of this article assist these suppliers in effectively globalizing by focusing on those precursors. We plan to verify the feasibility of the suggested solution to be actually tested as upcoming work. We suggest expanding the current multi-mode capital restricted project payment scheduling problem with the bonus-penalty construction to include resource restrictions in the decision model as a future research path. In addition, integrating the provided method with other techniques which were utilized to tackle several issues, like Convolutional Neural Networks (CNNs) (Dong et al. 2021) and clustered lifelong learning (BN 2021). Conclusion The outbreak of COVID-19 has caused many alternations in the societies (Vahdat et al. 2021a; Vahdat et al. 2021b). It is likely to have a substantial impact on the payment card industry. Contactless payment is touted as a more sanitary and secure method of payment. This problem encourages people to use their phones to pay for things. The COVID-19 encourages individuals to explore alternative payment methods when shopping to prevent touching cash and other items. Nevertheless, while the COVID-19 improves mobile payments, it is critical to keep digital and online transactions safe. Mobile payment service is also a key enabler for mobile commerce. It is a technology that enables the user to use the mobile phone and its applications to make requests to purchase a product, pay bills, bank bills, etc. In order for electronic payment systems to meet the user's needs properly, it is necessary to obtain user's satisfaction. Hence, reducing costs, time, and energy and improving NPV can be considered essential criteria for evaluating the success of mobile payment services. As a result, throughout the COVID-19 pandemic, a new approach is used to tackle mobile payment scheduling utilizing the HHO optimization algorithm. In this algorithm, some hawks attack a hunt to startle it (exploration phase). When escaping and fleeing the hunt, the hawks may conduct a series of rapid dives near the target to startle it and wear it out (exploitation phase). Depending on the fleeing potential of the victim, the algorithm may transition from exploring to exploiting and subsequently move among several exploitative modes. The simulation outcomes indicated that the proposed method could efficiently improve time, cost energy, and current net worth. Its performance is better than GA and outperforms ACO well. Appendix See Table 5Table 5 List of notations Project payment scheduling problem PPSP Max-net present value NPV Harris' hawks optimization HHO Payment scheduling negotiation problem PSNP Resource-constrained project scheduling problem RCPSP Nondominated sorting genetic algorithm II NSGA-II Region of interest ROI Simulated annealing SA Random sampling RS Multi-start iterative improvement MSII Tabu search TS Multi-swarm particle swarm optimization MPSO Ant colony optimization ACO The original online version of this article was revised: The fourth affiliation that belongs to the author “Mohammad Khalilzadeh” was incorrect. It has been corrected in this version. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Wen Sun, Yi-Peng Xu and Chen She have contributed equal to their work. ==== Refs References Afroz R Muhibbullah M Farhana P Morshed MN Analyzing the intention of the households to drop off mobile phones to the collection boxes: empirical study in Malaysia Ecofeminism Clim Change 2020 1 3 20 10.1108/EFCC-03-2020-0004 Aghajani G Ghadimi N Multi-objective energy management in a micro-grid Energy Rep 2018 4 218 225 10.1016/j.egyr.2017.10.002 Bn Z Representative task self-selection for flexible clustered lifelong learning 2021 New York IEEE Cao T The study of factors on the small and medium enterprises' adoption of mobile payment: implications for the COVID-19 era Front Public Health 2021 9 122 10.3389/fpubh.2021.646592 Chen Y Xu W Peng L Zhang H Light-weight and privacy-preserving authentication protocol for mobile payments in the context of IoT IEEE Access 2019 7 15210 15221 10.1109/ACCESS.2019.2894062 Chen X, Liu Z, Yu L, Li S, Gu L, Zeng X, Tan Y, Gu J (2021) Adversarial learning for incentive optimization in mobile payment marketing. Proceedings of the 30th ACM international conference on information & knowledge management. Dhamija D, Dhamija A (2022) A secure and reliable architecture for user authentication through OTP in mobile payment system. Proceedings of the international conference on paradigms of communication, computing and data sciences, Springer, Singapore Dizaj MVA, Moghaddam RA, Momenebellah S (2011) New mobile payment protocol: mobile pay center protocol (MPCP). 2011 3rd international conference on electronics computer technology, IEEE. Dong J Cong Y Sun G Fang Z Ding Z Where and how to transfer: knowledge aggregation-induced transferability perception for unsupervised domain adaptation IEEE Transact Pattern Anal Mach Intell 2021 10.1109/TPAMI.2021.3128560 Ebrahimian H Barmayoon S Mohammadi M Ghadimi N The price prediction for the energy market based on a new method Econ Research Ekon Istraž 2018 31 1 313 337 Elgamal ZM Yasin NBM Tubishat M Alswaitti M Mirjalili S An improved harris hawks optimization algorithm with simulated annealing for feature selection in the medical field IEEE Access 2020 8 186638 186652 10.1109/ACCESS.2020.3029728 Fang Z Lu J Liu F Xuan J Zhang G Open set domain adaptation: theoretical bound and algorithm IEEE Transact Neural Netw Learn Syst 2020 32 10 4309 4322 10.1109/TNNLS.2020.3017213 Gholizadeh E Afshar NB Solving a bi-objective resource constrained multi-mode project scheduling problem with regard to payment planning using the NSGA-II algorithm Inf J Paper 2018 8 165 187 He Z-W Liu R-J Hu X-B Yu X Client perspective based multimode project payment scheduling problem and its heuristic algorithm Syst Eng Theory Pract 2009 29 2 70 77 10.1016/S1874-8651(10)60038-5 He Z Wang N Li P Simulated annealing for financing cost distribution based project payment scheduling from a joint perspective Ann Oper Res 2014 213 1 203 220 10.1007/s10479-012-1155-9 Hegazy T Petzold K Genetic optimization for dynamic project control J Constr Eng Manag 2003 129 4 396 404 10.1061/(ASCE)0733-9364(2003)129:4(396) Heidari AA Mirjalili S Faris H Aljarah I Mafarja M Chen H Harris hawks optimization: algorithm and applications Futur Gener Comput Syst 2019 97 849 872 10.1016/j.future.2019.02.028 Jiao S Chong G Huang C Hu H Wang M Heidari AA Chen H Zhao X Orthogonally adapted Harris hawks optimization for parameter estimation of photovoltaic models Energy 2020 203 117804 10.1016/j.energy.2020.117804 Kolli CS Tatavarthi UD Fraud detection in bank transaction with wrapper model and Harris water optimization-based deep recurrent neural network 2020 Kybernetes Bingley Li X-M, Sun YL, Chen W-N, Zhang J (2017) Multi-swarm particle swarm optimization for payment scheduling. 2017 seventh international conference on information science and technology (ICIST), IEEE. Liao Y He Y Li F Zhou S Analysis of a mobile payment protocol with outsourced verification in cloud server and the improvement Comput Standards Interfaces 2018 56 101 106 10.1016/j.csi.2017.09.008 Lv Z Chen D Feng H Zhu H Lv H Digital twins in unmanned aerial vehicles for rapid medical resource delivery in epidemics IEEE Transact Intell Transp Syst 2021 10.1109/TITS.2021.3113787 Milenković BN Implementation of Harris Hawks Optimization (HHO) algorithm to solve engineering problems Tehnika 2021 76 4 439 446 10.5937/tehnika2104439M MortazaviNejad M Tareghian HR Sari Z Payment scheduling under project crashing based on project progress Iran J Numer Anal Optim 2017 7 2 39 56 Mukhopadhyay S Upadhyay P Institutional intervention in technology innovation: the struggle to increase mobile payment adoption 2022 Bingley Emerald Publishing Limited Sadrishojaei M Navimipour NJ Reshadi M Hosseinzadeh M A new preventive routing method based on clustering and location prediction in the mobile internet of things IEEE Internet Things J 2021 8 13 10652 10664 10.1109/JIOT.2021.3049631 SeyfiSariqaya M Chaharsooghi SK HusseinzadehKashan A Rahimnezhad F Multi-mode capital-constrained project payment scheduling problem with discounted cash flows Int J Indust Eng Manag Sci 2019 6 2 17 36 Shokouhyar S Dehkhodaei A Amiri B Toward customer-centric mobile phone reverse logistics: using the DEMATEL approach and social media data 2021 Kybernetes Bingley Thammarat C, Techapanupreeda C (2021). A secure mobile payment protocol for handling accountability with formal verification. 2021 international conference on information networking (ICOIN), IEEE Trinh BN Thang HQ Nguyen XT Luong PC Ho NK Applying a unified game-based model in a payment scheduling problem and design of experiments using MOEA framework 2019 SoMeT Hanoi University, Vietnam Vahdani H Shams A Multi-mode capital-constrained project payment scheduling model considering bonus-penalty structure Int J Manag Sci Eng Manag 2020 15 1 17 25 Vahdat S The role of IT-based technologies on the management of human resources in the COVID-19 era 2021 Kybernetes Bingley Vahdat S Samanian S Shahidi S Atapour A POS-497 characteristics and outcome of COVID-19 in patients on chronic hemodialysis in a dialysis center specific for COVID-19 Kidney Int Rep 2021 6 4 S215 10.1016/j.ekir.2021.03.524 Vahdat S Shahidi S Atapour A Reisizadeh S Soltaninejad F Maghami-Mehr A POS-214 The outcome of COVID-19 patients with acute kidney injury and the factors affecting mortality Kidney Int Rep 2021 6 4 S90 10.1016/j.ekir.2021.03.227 Vahidalizadehdizaj M, Leider A (2017) Mobile payment protocol 3d by using cloud messaging. Proceedings of student-faculty research day, CSIS, Pace university. Wang S Jia H Liu Q Zheng R An improved hybrid Aquila optimizer and Harris Hawks optimization for global optimization Math Biosci Eng 2021 18 7076 7109 10.3934/mbe.2021352 34814241 Yang Z Ghadamyari M Khorramdel H Alizadeh SMS Pirouzi S Milani M Banihashemi F Ghadimi N Robust multi-objective optimal design of islanded hybrid system with renewable and diesel sources/stationary and mobile energy storage systems Renew Sustain Energy Rev 2021 148 111295 10.1016/j.rser.2021.111295 Zhang ZX Chen WN Jin H Zhang J A preference biobjective evolutionary algorithm for the payment scheduling negotiation problem IEEE Transact Cybern 2020 51 12 6105 6118 10.1109/TCYB.2020.2966492 Zhang Z Wang X Sun L Mobile payment anomaly detection mechanism based on information entropy IET Netw 2016 5 1 1 7 10.1049/iet-net.2014.0101 Zhao C Liu X Zhong S Shi K Liao D Zhong Q Secure consensus of multi-agent systems with redundant signal and communication interference via distributed dynamic event-triggered control ISA Trans 2021 112 89 98 10.1016/j.isatra.2020.11.030 33309158 Zhao Y, Yu Y, Shakeel PM, Montenegro-Marin CE (2021b) Research on operational research-based financial model based on e-commerce platform. Inform Syst e-Bus Manag 1–17. Zhong L Fang Z Liu F Yuan B Zhang G Lu J Bridging the theoretical bound and deep algorithms for open set domain adaptation IEEE Transact Neural Netw Learn Syst 2021 10.1109/TNNLS.2021.3119965
PMC009xxxxxx/PMC9905755.txt	==== Front Neurol Sci Neurol Sci Neurological Sciences 1590-1874 1590-3478 Springer International Publishing Cham 36753010 6662 10.1007/s10072-023-06662-7 Original Article Current territorial organization for access to revascularization therapies for acute ischemic stroke in the Veneto region (Italy) from 2017 to 2021 http://orcid.org/0000-0002-3534-3201 Cappellari Manuel [email protected] 1 Bonetti Bruno 1 Baracchini Claudio 2 Corbetta Maurizio 2 De Boni Antonella 3 Critelli Adriana 4 Tonello Simone 5 Codemo Valentina 6 Marcon Michela 7 Turinese Emanuele 8 Bombardi Roberto 9 Basile Anna Maria 10 Ruzza Giampietro 11 Cadaldini Morena 12 Mampreso Edoardo 13 Marsala Sandro Zambito 14 Padoan Roberta 15 Marini Bruno 16 Gaudenzi Anna 17 Tonon Agnese 18 Masato Maela 19 Baldi Antonio 20 Turazzini Michelangelo 21 Zanette Giampietro 22 Adami Alessandro 23 Saia Mario 24 Bovi Paolo 25 1 grid.411475.2 0000 0004 1756 948X Stroke Unit, DAI Di Neuroscienze, Azienda Ospedaliera Universitaria Integrata, Piazzale A. Stefani 1, 37126 Verona, Italy 2 grid.411474.3 0000 0004 1760 2630 Stroke Unit, Azienda Ospedaliera Università Di Padova, Padova, Italy 3 grid.416303.3 0000 0004 1758 2035 Stroke Unit, Ospedale San Bortolo, Vicenza, Italy 4 grid.459845.1 0000 0004 1757 5003 Stroke Unit, Ospedale Dell’Angelo, Mestre, Italy 5 grid.413196.8 Stroke Unit, Ospedale Ca’ Foncello, Treviso, Italy 6 grid.415200.2 0000 0004 1760 6068 Stroke Unit, Ospedale Santa Maria Della Misericordia, Rovigo, Italy 7 Stroke Unit, Ospedale Cazzavillan, Arzignano, Italy 8 grid.416724.2 0000 0004 1759 6760 Stroke Unit, Ospedale San Bassiano, Bassano del Grappa, Italy 9 Stroke Unit, Ospedale Alto Vicentino, Santorso, Italy 10 grid.452765.7 0000 0004 0485 6404 Stroke Unit, Ospedale Sant’Antonio, Padova, Italy 11 Stroke Unit, Ospedale Di Cittadella, Cittadella, Italy 12 Stroke Unit, Ospedali Riuniti Padova Sud, Este, Schiavonia Italy 13 Stroke Unit, Ospedale Di Piove Di Sacco, Piove Di Sacco, Italy 14 Stroke Unit, Ospedale San Martino, Belluno, Italy 15 Stroke Unit, Ospedale Santa Maria del Prato, Feltre, Italy 16 grid.416363.5 0000 0004 1759 7835 Stroke Unit, Ospedale San Giacomo Apostolo, Castelfranco Veneto, Italy 17 grid.415855.8 Stroke Unit, Ospedale Santa Maria Dei Battuti, Conegliano Veneto, Italy 18 Stroke Unit, Ospedale Santi Giovanni E Paolo, Venezia, Italy 19 grid.417127.6 0000 0004 0484 5107 Stroke Unit, Ospedale Di Mirano, Mirano, Italy 20 Stroke Unit, Ospedale Di Portogruaro, Portogruaro, Italy 21 Stroke Unit, Ospedale Mater Salutis, Legnago, Italy 22 Stroke Unit, Ospedale Pederzoli, Peschiera del Garda, Italy 23 grid.416422.7 0000 0004 1760 2489 IRCCS Ospedale Sacro Cuore Don Calabria, Negrar, Italy 24 grid.466998.c 0000 0001 2369 6475 UOC Governo Clinico Assistenziale, Regione Veneto, Azienda Zero, Padova, Italy 25 Italian Stroke Association, Italy Verona, 8 2 2023 2023 44 6 20332039 24 12 2022 3 2 2023 © Fondazione Società Italiana di Neurologia 2023, corrected publication 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Introduction To evaluate the access to treatments with intravenous thrombolysis (IVT) and/or mechanical thrombectomy (MT) in acute ischemic stroke patients admitted to stroke units (SUs) of Veneto region (Italy) according to current “hub-and-spoke” model from 2017 to 2021. Patients and methods We retrospectively analyzed data on treatments with IVT and/or MT for stroke patients admitted to the 23 SUs (6 Hubs and 17 Spokes) of the 6 macro-areas including 9 local sanitary units (LSUs) and 2 hospitals. Results We reported 6093 treatments with IVT alone, 1114 with IVT plus MT, and 921 with MT alone. Number of stroke unit (SU) beds/100,000 inhabitants ranges from 2.3 to 2.8, and no difference was found among different macro-areas. Number of treatments/100,000 inhabitants/year ranges from 19 to 34 for IVT alone, from 2 to 7 for IVT plus MT, and from 2 to 5 for MT alone. Number of IVT alone/SU bed/year ranges from 9 to 21 in the Hub and from 6 to 12 in the Spokes. Rate of IVT plus MT in patients directly arrived in the same LSU’s Hub ranges from 50 to 81%, likewise the one of MT alone ranges from 49 to 84%. Conclusions Treatment target rates of IVT and MT set by Action Plan for Stroke in Europe 2018–2030 has been globally exceeded in the Veneto region. However, the target rate of MT and access revascularization treatments is heterogeneous among different macro-areas. Further efforts should be made to homogenize the current territorial organization. Supplementary Information The online version contains supplementary material available at 10.1007/s10072-023-06662-7. Keywords Thrombolysis Thrombectomy Stroke Hub-and-spoke model issue-copyright-statement© Fondazione Società Italiana di Neurologia 2023 ==== Body pmcIntroduction A survey conducted by Aguiar de Sousa et al. on intravenous thrombolysis (IVT) and endovascular treatment (EVT) in 44 European countries has observed major inequalities in acute stroke treatment between and within countries [1]. The survey has involved 1.5 stroke units (SUs) per 1000 annual incident ischemic strokes, nevertheless individual country-level data indicate that access to acute stroke care are insufficient, and differences inter/intra-country are considerable. Less than 20% of patients with acute ischemic stroke had access to IVT treatment, while the IVT overall treatment rate in incident ischemic stroke was 7.3%. EVT was performed in only 0.4 centers per 1000 annual incident ischemic strokes, whereas only 1.9% of all acute ischemic stroke patients have received the treatment. Based on previous data revealing that the access to revascularization therapies for acute ischemic stroke was restricted in several macro-areas, the European Stroke Organization (ESO) prepared a European Stroke Action Plan for the years 2018 to 2030 and set treatment target rates for all European countries [2]. We aimed to evaluate the access to treatments with IVT and/or mechanical thrombectomy (MT) in acute ischemic stroke patients admitted to the SUs of Veneto region (Italy) according to current “hub-and-spoke” model during a period of 5 years. Methods Study design, participants, and procedures We retrospectively analyzed prospectively collected data on acute revascularization treatments in ischemic stroke patients admitted at the SUs of Veneto region in Italy during a period of 5 years from January 1, 2017 to December 31, 2021. After defining the criteria for identifying the centers suitable for practicing IVT and the identification of specialized hospital centers authorized to use Alteplase for the treatment of acute ischemic stroke in the context of the SIST-MOST study (Veneto region deliberation DGR 1363 dated 07/mag/2004), stroke network has been established in the Veneto region at the end of 2008 according to a “hub-and-spoke” model (Veneto region deliberation DGR 4198 dated 30/dic/2008). The “hub-and-spoke” model included 6 Hubs (Mestre, Padova, Rovigo, Treviso, Verona, and Vicenza) and 17 Spokes (Arzignano, Bassano del Grappa, Belluno, Castelfranco Veneto, Cittadella, Feltre, Conegliano Veneto, Legnago, Mirano, Negrar, Padova Sant’Antonio, Peschiera del Garda, Piove di Sacco, Portogruaro, Santorso, Schiavonia/Monselice, and Venezia) (Supplemental Fig. 1). Spokes can perform IVT, while Hubs can perform both IVT and MT. According to the “hub-and-spoke stroke network”, patients admitted to a Spoke received IVT and were transferred to reference Hub to receive MT when they were eligible. From January 1, 2017, the geographical area of the Veneto region — a geographical area of 4,915,751 inhabitants — is divided into the following 9 local sanitary units (LSUs, public authorities of the Italian public administration, responsible for the provision of health services in a specific territory): LSU-1 “Dolomiti” (206,795 inhabitants), LSU-2 “Marca Trevigiana” (885,349 inhabitants), LSU-3 “Serenissima” (640,399 inhabitants), LSU-4 “Veneto Orientale” (215,391 inhabitants), LSU-5 “Polesana” (243,212 inhabitants), LSU-6 “Euganea” (934,659 inhabitants), LSU-7 “Pedemontana” (367,961 inhabitants), LSU-8 “Berica” (499,430 inhabitants), and LSU-9 “Scaligera” (922,555 inhabitants) (Veneto region law n. 19 dated 25/ott/2016) (Supplemental Fig. 2). The geographical area of the Veneto region includes also the Azienda Ospedaliera Padova (AO-PD) and the Azienda Ospedaliera Universitaria Integrata Verona (AOUI-VR). According to the “hub-and-spoke” model for stroke on the mapping of LSUs, six macro-areas are identified as follows: LSU-1 combined with LSU-2 (Treviso SU as Hub), LSU-3 combined with LSU-4 (Mestre SU as Hub), LSU-6 combined with AO-PD (Hub), LSU-7 combined with LSU-8 (Vicenza SU as Hub), and LSU-9 combined with AOUI-VR (Hub). LSU-5 is not combined (Rovigo SU as Hub). Stroke patients arrived at Rovigo (Hub) received MT during the daytime hours on weekdays and were referred to AO-PD (Hub) to perform MT during the night hours on weekdays and on holidays. CT angiography (CTA) was performed systematically at admission in stroke patients arrived at AOUI VR (Hub), Peschiera del Garda, Legnago, Arzignano, Bassano del Grappa, Belluno, and Mirano, whereas CTA was performed at admission in patients arrived at other Hubs and Spokes who had NIHSS score ≥ 6, ASPECT score ≥ 6, and pre-stroke mRS < 2 or < 3. CTA was performed at admission in stroke patients arrived at Feltre and Mirano during the daytime hours. LSU-7 and LSU-8 and have been equipped with automated computed tomography image (CTI) analysis software in the last year of study (2021). Data collection Data on number of IVT alone, IVT plus MT, and MT alone per year for each SU were collected by annual report of the regional coordinator of the Italian Stroke Association (ISA). Number of SU beds for each SU and criteria for CTA use and availability were recorded by the regional coordinator of the ISA. From 2009 to 2016, only data on the total number of IVTs per year in Hubs and Spokes were recorded. Total number of ischemic strokes among residents of Veneto region from 2017 to 2020 was collected according to administrative flows (DRG system, ICD code: (433.01, 433.11, 433.21, 433.31, 433.81, 433.91, 434.01, 434.11, 434.91, and 436). Data on total number of ischemic strokes among residents of Veneto region in 2021 were not available. Outcome measures For each macro-area, we calculated the following outcome measures for IVT alone and total IVT: (1) number of treatments/100,000 inhabitants/year; (2) number of treatments in the Hub/SU bed/year; (3) number of treatments in the Spoke/SU bed/year. In addition, we calculated the following outcomes for IVT plus MT, MT alone, and total MT: (1) number of treatments in patients of the same macro-area/100,000 inhabitants/ year; (2) number (%) of treatments in patients directly arrived at Hub of the same macro-area/total number of treatments in patients of the same macro-area; (3) number (%) of treatments in patients referred to another macro-area/total number of treatments; and (4) number (%) of treatments in patients arrived from another macro-area/total number of treatments. Statistical analysis We performed statistical analyses using SPSS 22.0 statistical package and STATA-16 software. Proportions were calculated for categorical variables, dividing the number of events by the total number. Categorical variables were expressed as frequency and percentage. The best macro-area was identified as reference for each outcome measure. Each macro-area was compared with the reference using χ2 test. Results During a period of 5 years (2017–2021), we reported 6093 treatments with IVT alone, 1114 treatments with IVT plus MT, and 921 treatments with MT alone for ischemic stroke in the six macro-areas of Veneto region. The number of treatments per year in LSU-1 and LSU-2 (Supplemental Table 1), LSU-3, and LSU-4 (Supplemental Table 2), LSU-5 (Supplemental Table 3), LSU-6 and AO-PD (Supplemental Table 4), LSU-7 and LSU-8 (Supplemental Table 5), LSU-9 and AOUI-VR (Supplemental Table 6) are provided in the online-only Data Supplement. Comparison of outcome measures among different macro-areas in IVT plus MT, and MT alone are reported in Table 1. No difference was found between LSU-5 (Reference: 2.8 SU beds) and other macro-areas on number of SU beds/100.000 inhabitants.Table 1 Comparison of outcome measures among different macro-areas in IVT plus MT, and MT alone LSU-1 Dolomiti, LSU.2 Marca Trevigiana LSU-3 Serenissima, LSU-4 Veneto Orientale LSU-5 Polesana LSU-6 Euganea, AO-PD LSU-7 Pedemontana, LSU-8 Berica LSU-9 Scaligera AOUI-VR Treviso—Hub Mestre—Hub Rovigo—Hub AO-PD—Hub Vicenza—Hub AOUI-VR—HUB P value P value P value P value P value P value SU beds/100,000 inhabitants/year 2.5 1.000 2.3 1.000 2.8 Reference 2.4 1.000 2.5 1.000 2.4 1.000 IVT alone Treatments/100,000 inhabitants/year 21 0.080 19 0.039* 27 0.370 23 0.145 26 0.302 34 Reference Treatments in the Hub/SU bed/year 10 0.048* 18 0.631 9 0.028* 20 0.876 10 0.048* 21 Reference Treatments in the Spoke/SU bed/year 12 Reference 6 0.157 0 NA** 8 0.371 10 0.670 10 0.670 IVT plus MT Treatments in patients of the same macro-area/100,000 inhabitants/year 2 0.096 4 0.366 7 Reference 5 0.564 5 0.564 6 0.782 Treatments in patients directly arrived at Hub of the same macro-area/Total treatments in patients of the same macro-area (%) 70 (52%) < 0.001* 86 (50%) < 0.001* 54 (100%) NA** 112 (52%) < 0.001* 119 (59%) < 0.001* 220 (81%) Reference Treatments in patients referred to another macro-area/total treatments (%) 3 (2%) < 0.001* 1 (< 1%) < 0.001* 34 (39%) Reference 1 (< 1%) < 0.001* 5 (2%) < 0.001* 0 < 0.001* Treatments in patients arrived from another macro-area/total treatments (%) 1 (< 1%) < 0.001* 2 (1%) < 0.001* 0 < 0.001* 36 (14%) Reference 2 (1%) < 0.001* 1 (< 1%) < 0.001* MT alone Treatments in patients of the same macro-area/100,000 inhabitants/year 2 0.257 4 0.739 4 0.739 5 Reference 4 0.739 3 0.480 Treatments in patients directly arrived at Hub of the same macro-area/total treatments in patients of the same macro-area (%) 74 (78%) 0.201 120 (66%) < 0.001* 33 (100%) NA** 158 (62%) < 0.001* 86 (49%) < 0.001* 134 (84%) Reference Treatments in patients referred to another macro-area/total treatments (%) 0 < 0.001* 1 (< 1%) < 0.001* 20 (38%) Reference 0 < 0.001* 0 < 0.001* 0 < 0.001* Treatments in patients arrived from another macro-area/total treatments (%) 1 (1%) 0.028* 0 < 0.001* 0 < 0.001* 19 (7%) Reference 1 (< 1%) 0.001* 0 < 0.001* * Significance, ** LSU 5 Polesana includes only Rovigo SU as Hub Regarding IVT alone, the number of treatments/100,000 inhabitants/year was lower in LSU-3/LSU-4 (n = 19), compared with those carried out by LSU-9/AOUI-VR (n = 34). The number of treatments in the Hub/SU bed/year was lower in LSU-1/LSU-2 (n = 10; p = 0.048), in LSU-5 (n = 9; p = 0.028), and in LSU-7/ LSU-8 (n = 10; p = 0.048), compared with the one processed by LSU-9/AOUI-VR (n = 21; reference). No difference was found for number of treatments in the Spoke/SU bed/year between LSU-1 and LSU-2 (n = 12 treatments; reference) and other macro-areas. About IVT plus MT, no difference was found for number of treatments in patients of the same macro-area/100,000 inhabitants/year between LSU-5 (n = 7; reference) and other macro-areas. The number (%) of treatments in patients directly arrived in the Hub of the same macro-area/total number of treatments in patients of the same macro-area was lower in LSU-1/LSU-2 (n = 70, 52%; p < 0.001), in LSU-3/LSU-4 (n = 86, 50%; p < 0.001), in LSU-6/AO-PD (n = 112, 52%; p < 0.001), and in LSU-7/LSU-8 (n = 119, 59%; p < 0.001), compared with LSU-9/AOUI-VR (n = 220 treatments, 81%; reference). Regarding MT alone, no difference was found for number of treatments in patients of the same macro-area/100,000 inhabitants/year between LSU-6/AO-PD (n = 7) and other macro-areas. number (%) of treatments in patients directly arrived at the Hub of the same macro-area was lower in LSU-3/LSU-4 (n = 120, 66%; p < 0.001), in LSU-6/AO-PD (n = 158, 62%, p < 0.001), in LSU-7/LSU-8 (n = 86, 49%, p < 0.001), compared with LSU-9/AOUI-VR (n = 134 treatments, 84%; reference). Comparison of outcome measures among different macro-areas in total IVT and total MT (Supplemental Table 7) are provided in the online-only Data Supplement. Total number of IVT per year in Hubs vs Spokes from 2009 to 2016 were the following: 192 vs 77 in 2009, 211 vs 146 in 2010, 266 vs 235 in 2011, 344 vs 231 in 2012, 407 vs 274 in 2013, 484 vs 465 in 2014, 564 vs 502 in 2015, and 667 vs 617 in 2016. Total number of ischemic strokes among residents of Veneto region from 2017 to 2020 was 6975 (142 per 100,000 inhabitants), in 2017, 6870 (140 per 100,000 inhabitants) in 2018, 6842 (139 per 100,000 inhabitants) in 2019, and 6344 (129 per 100,000 inhabitants) in 2020. Total number (%) of IVT alone on total number of ischemic strokes among residents of Veneto region was 1228 (17.6%) in 2017, 1281 (18.6%) in 2018, 1302 (19%) in 2019, 1143 (18%) in 2020, 1139 in 2021. Total number (%) of IVT plus MT on total number of ischemic strokes among residents of Veneto region was 170 (2.4%) in 2017, 212 (3.1%) in 2018, 241 (3.5%) in 2019, 241 (3.8%) in 2020, and 250 in 2021. Total number (%) of MT alone on total number of ischemic strokes among residents of Veneto region was 96 (1.4%) in 2017, 145 (2.1%) in 2018, 177 (2.6%) in 2019, 202 (3.2%) in 2020, and 301 in 2021. Discussion This study reports the number of treatments per 100,000 inhabitants annually performed in Veneto region (Italy) between 2017 and 2021, which ranged from 19 to 34 for IVT alone, from 2 to 7 for IVT plus MT and from 2 to 5 for MT alone in the different macro-areas. The global rate of IVT on total number of ischemic strokes among residents of Veneto region between 2017 and 2020 was more than 20%, while the global rate of MT exceeded 5% in 2018, reaching 7% in 2020. Our data shows that the number of treatments has grown progressively over the years and the treatment target rate of IVT and MT (i.e., the total number of treatments divided by the total number of patients with ischemic stroke and multiplied by 100) set by Action Plan for Stroke in Europe 2018–2030 [2], respectively at 15 and 5%, has been globally exceeded in Veneto region. However, our data show that the access to revascularization therapies is heterogeneous among different macro-areas, as reported by previous survey in 44 European countries [1]. Our study reports that the annual number of treatments per SU bed performed in the Hub ranges from 9 to 21 for IVT alone, while the one carried out for IVT alone per SU bed annually in the Spokes ranges from 6 to 12. These results have detected despite the number of SU beds per 100,000 inhabitants — from 2.3 to 2.8 SU beds per 100,000 inhabitants — is similar among different macro-areas. Only in one macro-area, the number of treatments per SU bed annually was lower in the Hub than in the Spokes (10 versus 12). The disparity of IVT use related to different geographic areas, volume centers, and levels of health care has already been reported [3]. Our study reports that rate of treatments with IVT plus MT ranges from 50 to 81% in patients directly arrived at the Hub of the same macro-area; similarly, rate of treatments with MT alone ranges from 49 to 84% in patients directly arrived at the Hub of the same macro-area. The transfer of patients from one macro-area to another to perform MT has almost never occurred, and was made only by Rovigo Hub of the LSU-5 that has benefited from the major capacity of AO-PD Hub of the LSU-6 for MT during the 12-night hours of weekdays and holidays. Our data confirm a previous our study enrolling 512 consecutive ischemic stroke patients who received IVT and/or MT, from September 17 to December 9, 2018, in 25 SUs in Triveneto, a geographical macro-area in Northeast of Italy. Previous study shows a net reduction of patients transferred from a Spoke to a Hub to receive MT, compared with those patients who are directly admitted to a Hub [4]. In line with the previous observations on “drip-and-ship” model [5], our study has also reported how onset-to-door time was shorter in the Spokes, while door-to-needle time and needle-to-groin puncture time were shorter in the Hubs. Our data are also consistent with a comprehensive population-wide data from 11 US states with 80 million residents showing that less than 50% of patients with ischemic stroke initially received care at facilities capable of MT [6]. Non-urban patients were less likely to initially receive care at the Hubs than residents of urban cores, and rural patients were particularly likely to present to thrombectomy gaps that did not offer transfer to a thrombectomy-capable hospital. Our study has some limitations. First, data on the number of ischemic stroke patients admitted to each SU per year was not available. Second, we are unable to exclude if the number of SU beds was reduced sometime during the observation period, especially in the Spokes. Third, we are unable to identify possible differences and changes during the observation period regarding health personnel for stroke patients among macro-areas, especially in the Spokes. These limitations mainly concern the period of the COVID-19 pandemic, especially the first wave of the pandemic. However, the observation period of the study is long and also includes the previous non-COVID-19 phase. Finally, we are unable to quantify how geographical differences of the local territory can affect the access to revascularization therapies for ischemic stroke among macro-areas, especially in the rural area. Despite these limitations, the present study is the first report to assess the efficiency of the “hub-and-spoke” model in stroke patients who received IVT and/or MT in the real life setting of an Italian region during a period of 5 years. Acute stroke care in hospitals is best performed in SUs, which are the essential part of the chain of recovery and form the backbone of pre-hospital, in-hospital, and post-hospital care. Nevertheless, the number of all stroke patients who are not treated in an SU as the first level remains in some regions of Europe still well below the target set by Action Plan for Stroke in Europe 2018–2030 (i.e., ≥ 90%). Future studies will be needed to verify if the target is achieved in the Veneto region. However, based on similar number of SU beds per inhabitants among different macro-areas, the Veneto region formally guarantees uniform access to care in the SU. Instead, access to IVT and/or MT for ischemic stroke is heterogeneous among different macro-areas. Since 2016, a new era has begun for the treatment of LVO-related stroke after five trials showed the effectiveness of EVT within 6 h from symptoms onset [7–12] and, since 2018, after two trials showed the effectiveness of EVT up to 16 and 24 h using advanced imaging [13, 14] . However, since its establishment in 2008, the stroke network of the Veneto region has not undergone changes. Because all patients should have uniform access to revascularization therapies for acute stroke, the regional system of care is called to reorganize himself. Equipping automated CTI analysis software should be mandatory for all Hubs and Spokes; it would be the fastest solution for the centralization of patients from Spokes to Hubs. Transferring interventional neuroradiologists to primary stroke centers to perform mechanical thrombectomy (“drip-and drive”) could be feasible. In order to guarantee a 24 h/7 d coverage, the strengthening of all Spokes and some Hubs should be the ideal solution. Alternatively, the regional health system should envisage a new “hub-and-spoke” model providing the centralization of all stroke patients eligible to revascularization treatments in the Hubs and a new role of Spokes in the immediate post-acute management of ischemic stroke. Finally, an update of the Action Plan for Stroke in Europe by 2030 should be required to redefine new more ambitious treatment target rates of IVT and MT based on current access in the most virtuous macro-areas. This is also because the number of ischemic stroke patients eligible to revascularization treatments is destined to increase with extending time window for treatment IVT and MT using advanced imaging according to new guidelines [15, 16] . Conclusions Treatment target rates of IVT and MT set by Action Plan for Stroke in Europe 2018–2030 have been globally exceeded in the Veneto region. However, access to revascularization treatments for ischemic stroke is heterogeneous among different macro-areas. Further efforts should be made to homogenize the current territorial organization. Supplementary Information Below is the link to the electronic supplementary material.Supplementary file1 (DOCX 217 KB) Data Availability Anonymized data will be shared by request from any qualified investigator. Declarations Ethical approval The present study was in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments. Informed consent Informed consent to use anonymized and aggregated data for participation in the studies including stroke patients treated with acute revascularization treatments was obtained from all the patients of each center. Competing interests The authors declare no competing interests. The original online version of this article was revised: The original article contains an error, a typo in the surname of a co-author. Author asked to change Maela Masa to Maela Masato. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Change history 6/9/2023 A Correction to this paper has been published: 10.1007/s10072-023-06890-x ==== Refs References 1. Aguiar de Sousa D von Martial R Abilleira S Access to and delivery of acute ischaemic stroke treatments: a survey of national scientific societies and stroke experts in 44 European countries Eur Stroke J. 2019 4 13 28 10.1177/2396987318786023 31165091 2. Norrving B Barrick J Davalos A Action plan for stroke in Europe 2018–2030 Eur Stroke J 2018 3 309 336 10.1177/2396987318808719 31236480 3. Seabury S Bognar K Xu Y Regional disparities in the quality of stroke care Am J Emerg Med 2017 35 1234 1239 10.1016/j.ajem.2017.03.046 28431874 4. Cappellari M Bonetti B Forlivesi S Acute revascularization treatments for ischemic stroke in the stroke units of Triveneto, northeast Italy: time to treatment and functional outcomes J Thromb Thrombolysis 2021 51 159 167 10.1007/s11239-020-02142-3 32424778 5. Saver JL Goyal M van der Lugt A Time to treatment with endovascular thrombectomy and outcomes from ischemic stroke: a meta-analysis JAMA 2016 316 1279 1288 10.1001/jama.2016.13647 27673305 6. Kamel H Parikh NS Chatterjee A Access to mechanical thrombectomy for ischemic stroke in the United States Stroke 2021 52 2554 2561 10.1161/STROKEAHA.120.033485 33980045 7. Goyal M Menon BK van Zwam WH Endovascular thrombectomy after large-vessel ischaemic stroke: a meta-analysis of individual patient data from five randomised trials Lancet 2016 387 1723 1731 10.1016/S0140-6736(16)00163-X 26898852 8. Berkhemer OA Fransen PS Beumer D A randomized trial of intraarterial treatment for acute ischemic stroke N Engl J Med 2015 372 11 20 10.1056/NEJMoa1411587 25517348 9. Goyal M Demchuk AM Menon BK Randomized assessment of rapid endovascular treatment of ischemic stroke N Engl J Med 2015 372 1019 1030 10.1056/NEJMoa1414905 25671798 10. Saver JL Goyal M Bonafe A Stent-retriever thrombectomy after intravenous t-PA vs. t-PA alone in stroke N Engl J Med. 2015 372 2285 2295 10.1056/NEJMoa1415061 25882376 11. Campbell BC Mitchell PJ Kleinig TJ Endovascular therapy for ischemic stroke with perfusion-imaging selection N Engl J Med 2015 372 1009 1018 10.1056/NEJMoa1414792 25671797 12. Jovin TG Chamorro A Cobo E Thrombectomy within 8 hours after symptom onset in ischemic stroke N Engl J Med 2015 372 2296 2306 10.1056/NEJMoa1503780 25882510 13. Nogueira RG Jadhav AP Haussen DC Thrombectomy 6 to 24 hours after stroke with a mismatch between deficit and infarct N Engl J Med 2018 378 11 21 10.1056/NEJMoa1706442 29129157 14. Albers GW Marks MP Kemp S Thrombectomy for stroke at 6 to 16 hours with selection by perfusion imaging N Engl J Med 2018 378 708 771 10.1056/NEJMoa1713973 29364767 15. Berge E Whiteley W Audebert H European Stroke Organisation (ESO) guidelines on intravenous thrombolysis for acute ischaemic stroke Eur Stroke J 2021 6 I LXII 10.1177/2396987321989865 33817340 16. Turc G Bhogal P Fischer U European Stroke Organisation (ESO)- European Society for Minimally Invasive Neurological Therapy (ESMINT) guidelines on mechanical thrombectomy in acute ischemic stroke J Neurointerv Surg 2019 11 535 538 10.1136/neurintsurg-2018-014568 31152058
PMC009xxxxxx/PMC9909660.txt	==== Front Silicon Silicon 1876-990X 1876-9918 Springer Netherlands Dordrecht 2332 10.1007/s12633-023-02332-7 Original Paper Effect of green synthesis bimetallic Ag@SiO2 core–shell nanoparticles on absorption behavior and electrical properties of PVA-PEO nanocomposites for optoelectronic applications Al-Bermany Ehssan [email protected] 1 Mekhalif Ali Tao’mah 2 Banimuslem Hikmat A. 2 Abdali Karar 3 Sabri Mohammed M. 4 1 grid.427646.5 0000 0004 0417 7786 Physics Department College of Education for Pure Sciences, University of Babylon, Babylon, Iraq 2 grid.427646.5 0000 0004 0417 7786 Physics Department College of Science, University of Babylon, Babylon, Iraq 3 Iraq Ministry of Education, Baghdad, Iraq 4 grid.440835.e 0000 0004 0417 848X Department of Physics Faculty of Science and Health, Koya University, Koya KOY45 Kurdistan Region F. R, Erbil, Iraq 9 2 2023 2023 15 9 40954107 15 9 2022 3 2 2023 © The Author(s), under exclusive licence to Springer Nature B.V. 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. A green and easy technique was used to synthesize silver and silica (Ag@SiO2) core–shell nanoparticles (NPs) in the matrix blend polymers matrix. Core–shell nanoparticles were loaded into polyvinyl alcohol (PVA) and ultrahigh molecular weight polyethylene oxide (UHMW-PEO) blended polymer to fabricate new nanocomposite films (NCFs) using the developed solution-sonication-casting technique. The spectroscopic properties of the resultant films were investigated using x-ray diffraction (XRD), Fourier transforms infrared (FTIR), visible light microscope (OLM), field emission scanning electron microscope (FESEM), FESEM-energy dispersive spectroscope (FESM-EDX), UV/visible spectrometer, and LCR meter to investigate the structural, morphological, optical, and electrical characteristics. XRD revealed the presence of the semi-crystalline nature of PVA-UHMWPEO/ Ag@SiO2 NCFs. The degree of crystallinity increased after embedding. The NPs were well distributed within the NCFs according to OLM and SEM, and FESM-EDX confirmed the presence of C, O, Si, and Ag elements. FTIR spectrum observed strong bonding after the loading of NPs, and other peaks were hidden. The UV/visible spectrums suggested an absorption at ~ 210 nm. Based on the Tauc plot model, the optical bandgap (Eg) values decreased from 5.52 eV to 4.57 eV. The electrical conductivity values were significantly increased with the increasing frequency and (Ag@SiO2) core–shell nanoparticles (NPs) loading ratio. The PVA-UHMWPEO/Ag@SiO2 NCFs explained enhanced lattice strain. The obtained NCFs are suitable for use in various optoelectronic and nanodevice applications. Keywords PVA/UHMWPEO Ag@SiO2 Core–shell nanoparticles Nanocomposites issue-copyright-statement© Springer Nature B.V. 2023 ==== Body pmcAcknowledgements The authors would like to thank the department of physics, university of Babylon, Iraq, for their support. Authors' Contributions Ehssan Al-Bermany designed, wrote, and analyzed the FTIR, XRD, SEM, and OML and improved and reviewed the paper. Ali Tao'mah Mekhalif performed all the experiments, and Hikmat A Banimuslem performed and wrote the experiments and contributed to the introduction section. Karar Abdali contributed to the optical properties and data examination, and Mohammed M. Sabri analyzed the electrical properties of the research and data examination. All authors read and approved the final manuscript. Funding No funding applied. Data Availability The data are available in the manuscript. Declarations Competing interests The authors declare no competing interests. Ethics Approval Not applicable. Consent to Participate Not applicable. Consent for Publication Not applicable. Conflict of Interest The authors declare that they have no conflict of interest. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Smith RC Liang C Landry M The mechanisms leading to the useful electrical properties of polymer nanodielectrics IEEE Trans Dielectr Electr Insul 2008 15 187 196 10.1109/T-DEI.2008.4446750 2. Tanaka T, Vaughan AS (2022) Tailoring of nanocomposite dielectrics : from fundamentals to devices and applications. 441. 10.1201/9781315201535 3. Abdali K Structural, Morphological, and Gamma Ray Shielding (GRS) Characterization of HVCMC/PVP/PEG Polymer Blend Encapsulated with Silicon Dioxide Nanoparticles. Silicon 1–6 (2022). 10.1007/s12633-022-01678-8 4. Abdelamir AI, Al-Bermany E, Hashim FS Important factors affecting the microstructure and mechanical properties of PEG/GO-based nanographene composites fabricated applying assembly-acoustic method. In: AIP Conference Proceedings. p 020110 (2020) 5. Aldulaimi NR Al-Bermany E Tuning the bandgap and absorption behaviour of the newly-fabricated Ultrahigh Molecular weight Polyethylene Oxide- Polyvinyl Alcohol/ Graphene Oxide hybrid nanocomposites Polym Polym Compos 2022 30 096739112211121 10.1177/09673911221112196 6. Chaudhary P Fatima F Kumar A Relevance of Nanomaterials in Food Packaging and its Advanced Future Prospects J Inorg Organomet Polym Mater 2020 30 5180 5192 10.1007/s10904-020-01674-8 32837459 7. Menazea AA Ismail AM Awwad NS Ibrahium HA Physical characterization and antibacterial activity of PVA/Chitosan matrix doped by selenium nanoparticles prepared via one-pot laser ablation route J Market Res 2020 9 9598 9606 10.1016/j.jmrt.2020.06.077 8. Abd El-Kader MFH Elabbasy MT Ahmed MK Menazea AA Structural, morphological features, and antibacterial behavior of PVA/PVP polymeric blends doped with silver nanoparticles via pulsed laser ablation J Market Res 2021 13 291 300 10.1016/j.jmrt.2021.04.055 9. El-Kader MFHA, Elabbasy MT, Adeboye AA, Menazea AA Nanocomposite of PVA/PVP blend incorporated by copper oxide nanoparticles via nanosecond laser ablation for antibacterial activity enhancement. Polymer Bulletin 1–18 (2021). 10.1007/s00289-021-03975-5 10. Kadhim MA Al-Bermany E New fabricated PMMA-PVA/graphene oxide nanocomposites: Structure, optical properties and application J Compos Mater 2021 55 2793 2806 10.1177/0021998321995912 11. Menazea AA One-Pot Pulsed Laser Ablation route assisted copper oxide nanoparticles doped in PEO/PVP blend for the electrical conductivity enhancement J Market Res 2020 9 2412 2422 10.1016/j.jmrt.2019.12.073 12. Ghazi RA Al-Mayalee KH Al-Bermany E Impact of polymer molecular weights and graphene nanosheets on fabricated PVA-PEG/GO nanocomposites: Morphology, sorption behavior and shielding application AIMS Materials Science 2022 9 584 603 10.3934/matersci.2022035 13. Abdali K Synthesis, characterization and USW sensor of PEO/PMMA/PVP doped with zirconium dioxide nanoparticles Trans Electr Electron Mater 2022 10.1007/s42341-022-00388-7 14. Cao G Brinker CF Annual Review of Nano Res 2008 1 645 15. Bigg DM Mechanical, thermal, and electrical properties of metal fiber-filled polymer composites Polym Eng Sci 1979 19 1188 1192 10.1002/pen.760191610 16. Szabo A Theory of fluorescence depolarization in macromolecules and membranes J Chem Phys 1984 81 150 167 10.1063/1.447378 17. Hamida RS Abdelmeguid NE Ali MA Synthesis of Silver Nanoparticles Using a Novel Cyanobacteria Desertifilum sp. extract: Their Antibacterial and Cytotoxicity Effects Int J Nanomed 2020 15 49 63 10.2147/IJN.S238575 18. Assis M Simoes LGP Tremiliosi GC Sio2-ag composite as a highly virucidal material: A roadmap that rapidly eliminates sars-cov-2 Nanomaterials 2021 11 1 19 10.3390/nano11030638 19. Sakthisabarimoorthi A Martin Britto Dhas SA Jose M Nonlinear optical properties of Ag@SiO2 core-shell nanoparticles investigated by continuous wave He-Ne laser Mater Chem Phys 2018 212 224 229 10.1016/j.matchemphys.2018.03.047 20. Asselin J Legros P Grégoire A Boudreau D Correlating Metal-Enhanced Fluorescence and Structural Properties in Ag@SiO2 Core-Shell Nanoparticles Plasmonics 2016 11 1369 1376 10.1007/s11468-016-0186-5 21. Wang J White WB Adair JH Optical properties of core–shell structured Ag/SiO2 nanocomposites Mater Sci Eng, B 2010 166 235 238 10.1016/j.mseb.2009.11.026 22. Liang Y Ouyang J Wang H Synthesis and characterization of core-shell structured SiO 2 @YVO 4: Yb 3+, Er 3+ microspheres Appl Surf Sci 2012 258 3689 3694 10.1016/j.apsusc.2011.12.006 23. Das MR Sarma RK Saikia R Synthesis of silver nanoparticles in an aqueous suspension of graphene oxide sheets and its antimicrobial activity Colloids Surf, B 2011 83 16 22 10.1016/j.colsurfb.2010.10.033 24. Gün Gök Z Synthesis and characterization of polyvinyl alcohol–silk sericin nanofibers containing gelatin-capped silver nanoparticles for antibacterial applications Polym Bull 2022 166 235 238 10.1007/s00289-022-04455-0 25. Sakthisabarimoorthi A Jose M Martin Britto Dhas SA Jerome Das S Fabrication of Cu@Ag core–shell nanoparticles for nonlinear optical applications J Mater Sci: Mater Electron 2017 28 4545 4552 10.1007/s10854-016-6090-0 26. Al-shammari AK Al-Bermany E Polymer functional group impact on the thermo-mechanical properties of polyacrylic acid, polyacrylic amide- poly (vinyl alcohol) nanocomposites reinforced by graphene oxide nanosheets J Polym Res 2022 29 351 10.1007/s10965-022-03210-3 27. Kandulna R Choudhary RB Concentration-dependent behaviors of ZnO-reinforced PVA–ZnO nanocomposites as electron transport materials for OLED application Polym Bull 2018 75 3089 3107 10.1007/s00289-017-2186-9 28. Yang Z Zhang Y Wen B Enhanced electromagnetic interference shielding capability in bamboo fiber@polyaniline composites through microwave reflection cavity design Compos Sci Technol 2019 178 41 49 10.1016/j.compscitech.2019.04.023 29. Qiu M Zhang Y Wen B Facile synthesis of polyaniline nanostructures with effective electromagnetic interference shielding performance J Mater Sci: Mater Electron 2018 29 10437 10444 10.1007/s10854-018-9100-6 30. Cao Y-C Xu C Wu X A poly (ethylene oxide)/graphene oxide electrolyte membrane for low temperature polymer fuel cells J Power Sources 2011 196 8377 8382 10.1016/j.jpowsour.2011.06.074 31. Ramalla I Gupta RK Bansal K Effect on superhydrophobic surfaces on electrical porcelain insulator, improved technique at polluted areas for longer life and reliability Inter J. of Eng & Techol 2015 4 509 10.14419/ijet.v4i4.5405 32. Oje AI Ogwu AA Mirzaeian M Tsendzughul N Electrochemical energy storage of silver and silver oxide thin films in an aqueous NaCl electrolyte J Electroanal Chem 2018 829 59 68 10.1016/j.jelechem.2018.10.001 33. Gaabour LH Influence of silica nanoparticles incorporated with chitosan/polyacrylamide polymer nanocomposites J Market Res 2019 8 2157 2163 10.1016/j.jmrt.2019.02.003 34. Pankove JI Kiewit DA Optical Processes in Semiconductors J Electrochem Soc 1972 119 156C 10.1149/1.2404256 35. Hussein AM Dannoun EMA Aziz SB Steps toward the band gap identification in polystyrene based solid polymer nanocomposites integrated with tin titanate nanoparticles Polymers 2020 12 1 21 10.3390/polym12102320 36. Ji KA Design M Chemistry A Electrical properties of poly ( n-butylamino ) J Mater Sci 1998 3 2955 2959 37. Shekhar S Prasad V Subramanyam SV Structural and electrical properties of composites of polymer-iron carbide nanoparticles embedded in carbon Mater Sci and Eng B: Solid-State Mater for Adv Technol 2006 133 108 112 10.1016/j.mseb.2006.06.010 38. Hayany AT (1970) Solid dielectric waveguide filters 39. Hu H Zhang F Luo S Recent advances in rational design of polymer nanocomposite dielectrics for energy storage Nano Energy 2020 74 104844 10.1016/j.nanoen.2020.104844 40. Tareev BM Tareev BM Physics of Dielectric Materials 1979 Moscow Mir Publ 90 41. Al-Abbas SS Ghazi RA Al-shammari AK Influence of the polymer molecular weights on the electrical properties of Poly(vinyl alcohol) – Poly(ethylene glycols)/Graphene oxide nanocomposites Mater Today Proc 2021 42 2469 2474 10.1016/j.matpr.2020.12.565 42. Coetzee D, Venkataraman M, Militky J, Petru M (2020) Influence of nanoparticles on thermal and electrical conductivity of composites. Polymers 12, 10.3390/POLYM12040742 43. Abdali K Structural, optical, electrical properties, and relative humidity sensor application of PVA/Dextrin polymeric blend loaded with silicon dioxide nanoparticles J Mater Sci: Mater Electron 2022 33 18199 18208 10.1007/s10854-022-08676-x 44. Hezma AM Elashmawi IS Rajeh A Kamal M Change Spectroscopic, thermal and mechanical studies of PU/PVC blends Physica B 2016 495 4 10 10.1016/j.physb.2016.04.043 45. Patla SK Mukhopadhyay M Ray R Ion specificity towards structure-property correlation of poly (ethylene oxide) [PEO]-NH 4 I and PEO-KBr composite solid polymer electrolyte Ionics 2019 25 627 639 10.1007/s11581-018-2711-3 46. Buraidah MH Teo LP Majid SR Arof AK Ionic conductivity by correlated barrier hopping in NH4I doped chitosan solid electrolyte Physica B 2009 404 1373 1379 10.1016/j.physb.2008.12.027 47. Prajapati GK Roshan R Gupta PN Effect of plasticizer on ionic transport and dielectric properties of PVAH3PO4 proton conducting polymeric electrolytes J Phys Chem Solids 2010 71 1717 1723 10.1016/j.jpcs.2010.08.023 48. Weng L Wang X Zhang X The effect of Ag@SiO2 core-shell nanoparticles on the dielectric properties of PVDF based nanocomposites Polym Compos 2020 41 2245 2253 10.1002/pc.25535
PMC009xxxxxx/PMC9912810.txt	==== Front J Am Acad Dermatol J Am Acad Dermatol Journal of the American Academy of Dermatology 0190-9622 1097-6787 by the American Academy of Dermatology, Inc. S0190-9622(23)00175-5 10.1016/j.jaad.2023.02.002 Research Letter Tumor necrosis factor inhibitors and methotrexate are associated with decreased COVID-19-related hospitalization: Follow up of “Clinical outcomes of COVID-19 in patients taking tumor necrosis factor inhibitors and methotrexate” Cahn Rachel Tallman MD ∗ Zinn Zachary MD Kolodney Michael S. MD, PhD ∗∗ Department of Dermatology, West Virginia University, Morgantown, West Virginia ∗ Correspondence to: Rachel Tallman Cahn, MD, Department of Dermatology, West Virginia University, 1 Medical Center Dr, HSC PO Box 9158, Morgantown, WV 26506-9158 ∗∗ Reprint requests: Michael S. Kolodney, MD, PhD, Department of Dermatology, West Virginia University, 1 Medical Center Dr, HSC PO Box 9158, Morgantown, WV 26506-9158 10 2 2023 6 2023 10 2 2023 88 6 13851386 © 2023 by the American Academy of Dermatology, Inc. 2023 American Academy of Dermatology, Inc. Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Key words coronavirus COVID-19 methotrexate SARS-CoV-2 TNF-alpha tumor necrosis factor-alpha inhibitor ==== Body pmcTo the Editor: Earlier in the COVID-19 pandemic, we studied the effects of tumor necrosis factor inhibitors (TNFis) and methotrexate (MTX) on disease severity following COVID-19. There were fewer patients on these therapies who required hospitalization or died compared to controls; however, this association was insignificant.1 A study conducted during this period by Veenstra and coworkers also examined the relationship between TNFi and COVID-19, and found these medications to be associated with less severe disease.2 Another study found MTX was associated with reduced mortality.3 Since a much greater number of COVID-19 cases are now available for analysis, we re-examined the TriNetX database to clarify the relationship between COVID-19 severity and MTX or TNFi exposure. TriNetX is a global federated research network that provides access to statistics on electronic medical records across 66 health care organizations, as described previously.1 Since our prior study, the TriNetX COVID-19 research network has almost doubled in size from over 53 million to over 95 million patients. Those with a COVID-19-related diagnosis since January 20, 2020 also increased from 32,076 to over 1.7 million. Among adults with documented COVID-19, 24,068 were exposed to a TNFi or MTX within 1 year before diagnosis compared with our previous cohort of 214 patients. We queried the TriNetX COVID-19 research network on June 14, 2022 for adult patients with documented exposure to a TNFi (adalimumab, infliximab, etanercept, certolizumab, or golimumab) or MTX within 1 year of COVID-19 diagnosis. Outcomes examined were hospitalization or death within 45 days of COVID-19 diagnosis. Cohorts included TNFi and MTX as well as patients on both medications. 1:1 propensity score matching was performed for comorbidities associated with poor COVID-19-related outcomes (Supplementary Tables I and II, available via Mendeley at https://doi.org/10.17632/tvvwmbry4h.2).4 Analyses were assembled using the International Classification of Diseases, 10 th Revision, Clinical Modification diagnoses and terminology recommended by the World Health Organization and Centers for Disease Control and Prevention (Supplementary Appendix, available via Mendeley at https://doi.org/10.17632/tvvwmbry4h.2). For each matched group, the likelihood of hospitalization was significantly decreased. Risk differences were 2.786% in the combined TNFi/MTX group (risk ratio [RR] = 0.860 [95% CI 0.828, 0.893]), 2.933% in the TNFi group (RR = 0.841 [95% CI 0.781, 0.907]), and 2.952% in the MTX group (RR = 0.863 [95% CI 0.821, 0.908]) for hospitalization (Fig 1 ). Mortality for matched groups did not reach significance with risk differences of 0.087% for TNFi/MTX, 0.385% for TNFi, and 0.016% for MTX (RR = 0.961 [95% CI 0.854, 1.083], RR = 0.776 [95% CI 0.59, 1.02], RR = 1.006 [95% CI 0.866, 1.168], respectively) (Fig 2 ).Fig 1 Risk of hospitalization within 45 days of COVID-19. Risk ratios and 95% CIs were calculated to assess the likelihood of hospitalization within 45 days of receiving a diagnosis associated with COVID-19 in patients on methotrexate or tumor necrosis factor inhibitor after 1:1 propensity matching. MTX, Methotrexate; TNFi, tumor necrosis factor inhibitor. ∗P < .05 was considered significant. Fig 2 Risk of mortality within 45 days of COVID-19. Risk ratios and 95% CIs were calculated to assess the likelihood of mortality within 45 days of receiving a diagnosis associated with COVID-19 in patients on methotrexate or tumor necrosis factor inhibitor after 1:1 propensity matching. MTX, Methotrexate; TNFi, tumor necrosis factor inhibitor. ∗P < .05 was considered significant. Consistent with the study by Veenstra and coworkers, our results suggest that patients on MTX and TNFi are not at increased risk of more severe COVID-19-related sequelae and that TNFi may be associated with less severe disease.2 Ours are among the first to suggest MTX may also be associated with milder COVID-19. These findings continue to support ongoing use of TNFi and MTX without interruption due to fear of worse COVID-19 outcomes and also support the rationale for ongoing randomized trials testing TNFi and MTX as therapy for COVID-19.5 Conflicts of interest None disclosed. Funding sources: None. IRB approval status: Not applicable. ==== Refs References 1 Yousaf A. Gayam S. Feldman S. Zinn Z. Kolodney M. Clinical outcomes of COVID-19 in patients taking tumor necrosis factor inhibitors or methotrexate: a multicenter research network study J Am Acad Dermatol 84 1 2021 70 75 10.1016/j.jaad.2020.09.009 32926977 2 Veenstra J. Buechler C.R. Robinson G. Antecedent immunosuppressive therapy for immune-mediated inflammatory diseases in the setting of a COVID-19 outbreak J Am Acad Dermatol 83 6 2020 1696 1703 10.1016/j.jaad.2020.07.089 32735965 3 FAI2R /SFR/SNFMI/SOFREMIP/CRI/IMIDIATE consortium and contributors Severity of COVID-19 and survival in patients with rheumatic and inflammatory diseases: data from the French RMD COVID-19 cohort of 694 patients Ann Rheum Dis 80 4 2021 527 538 10.1136/annrheumdis-2020-218310 33268442 4 Jordan R.E. Adab P. Cheng K.K. Covid-19: risk factors for severe disease and death BMJ 368 2020 m1198 32217618 5 Hachem H. Godara A. Schroeder C. Rapid and sustained decline in CXCL-10 (IP-10) annotates clinical outcomes following TNFα-antagonist therapy in hospitalized patients with severe and critical COVID-19 respiratory failure J Clin Transl Sci 5 1 2021 e146 10.1017/cts.2021.805 34457357
PMC009xxxxxx/PMC9918433.txt	==== Front Can J Cardiol Can J Cardiol The Canadian Journal of Cardiology 0828-282X 1916-7075 Canadian Cardiovascular Society. Published by Elsevier Inc. S0828-282X(23)00130-7 10.1016/j.cjca.2023.02.005 Research Letters The COVID-19 Pandemic Did Not Adversely Affect Follow-up Patterns for Patients With Heart Failure Discharged From Emergency Departments McAlister Finlay A. MD, MSc Dong Yuan MMath University of Alberta and Alberta Strategy for Patient Oriented Research Support Unit, Edmonton, Alberta, Canada 11 2 2023 6 2023 11 2 2023 39 6 824825 © 2023 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved. 2023 Canadian Cardiovascular Society Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcIn patients with heart failure (HF) released from an emergency department (ED), timely follow-up care (within 7 days ideally, but even up to 30 days) is associated with lower rates of hospitalization or death.1 , 2 Because it is unknown whether the COVID-19 pandemic adversely affected prompt follow-up after ED visits for patients with HF, we conducted a retrospective cohort study using linked administrative health care databases for the entire Canadian province of Alberta and compared outpatient care for patients seen and discharged from an ED between March 1, 2019, to February 29, 2020 (“prepandemic”) vs March 1, 2020, to February 28, 2021 (“pandemic”). This was a substudy from a larger study of all health care encounters for 3.1 million Albertan adults prepandemic vs pandemic and full details on methodology and case definitions have been previously published.3 In this substudy, we examined rates of follow-up with any physician (primary care physician or specialist) for patients who were treated and released from an ED in Alberta with a primary diagnosis of HF in the year prepandemic (n = 5015) and during the first year of the pandemic (n = 3693). Of note, we only included the first ED visit for HF for each patient in this substudy. Demographic characteristics and comorbidity burdens of the patients were similar in both years. There were no appreciable differences in the frequency of outpatient follow-up within 7 days, 14 days, or 30 days of an ED visit for HF in Albertan adults in the 12 months pre- and postpandemic onset (Table 1 ), although approximately one-third of outpatient encounters were virtual in the first year of the pandemic (compared with none prepandemic). However, the proportion who were seen by a specialist within each of the time frames after ED discharge was lower during the pandemic than prepandemic (all P < 0.01; Table 1), which is not surprising because many specialists are based in acute care facilities where outpatient in-person visits were most stringently restricted. There was also no statistically significant difference in short-term outcomes after ED discharge during the pandemic vs the previous year (Table 1), even after adjustment for age, sex, Charlson Comorbidity Index score, urban residence, and Pampalon Deprivation Index: adjusted odds ratio (aOR), 1.12 (95% confidence interval [CI], 0.95-1.32) at 7 days; aOR, 1.05 (95% CI, 0.92-1.20) at 14 days; and aOR, 1.06 (95% CI, 0.95-1.18) at 30 days.Table 1 Baseline characteristics and frequency of outpatient follow-up after being discharged from an emergency department for a primary diagnosis of HF Prepandemic (March 1, 2019 to February 28, 2020; n = 5015) Pandemic (March 1, 2020 to February 28, 2021; n = 3693) P value pandemic vs prepandemic time frames Median age (IQR), years 75.0 (64.0-83.0) 74.0 (64.0-83.0) 0.79 Female sex 2025 (40.4) 1518 (41.1) 0.50 Charlson Comorbidity Index score, excluding HF Mean (SD) 2.56 (2.23) 2.49 (2.27) 0.16 Median (IQR) 2.00 (1.00, 4.00) 2.00 (1.00, 4.00) 0.06 Urban residence 3922 (78.2) 2866 (77.6) 0.51 Pampalon Deprivation Index 1 (least deprived) 707 (14.1) 497 (13.5) 0.79 2 785 (15.7) 584 (15.8) 3 825 (16.5) 598 (16.2) 4 1049 (20.9) 817 (22.1) 5 (most deprived) 1196 (23.8) 874 (23.7) Missing 453 (9.0) 323 (8.7) Outpatient physician follow-up within 7 days∗ 3526 (70.3); all in-person 2620 (70.9); 893 virtual and 1727 in-person 0.52 Outpatient follow-up with a specialist within 7 days∗,† 2065 (41.2% of all patients and 58.6% of outpatient visits in that time frame) 1302 (35.3% of all patients and 49.7% of outpatient visits in that time frame); 403 virtual and 899 in-person < 0.01 Outpatient physician follow-up within 14 days∗,† 3904 (83.4); all in-person 2860 (83.6); 981 virtual and 1879 in-person 0.80 Outpatient follow-up with a specialist within 14 days∗,† 2388 (47.6% of all patients and 61.2% of outpatient visits in that time frame) 1584 (42.9% of all patients and 55.4% of outpatient visits in that time frame); 505 virtual and 1079 in-person < 0.01 Outpatient physician follow-up within 30 days 4103 (92.8); all in-person 3011 (92.6); 1055 virtual and 1956 in-person 0.81 Outpatient follow-up with a specialist within 30 days∗,† 2886 (57.5% of all patients and 70.3% of outpatient visits in that time frame) 2015 (54.6% of all patients and 66.9% of outpatient visits in that timeframe) 671 virtual and 1344 in-person 0.06 Hospitalized or died within 7 days 335 (6.7) 273 (7.4) 0.20 Hospitalized or died within 14 days 578 (11.5) 442 (12.0) 0.53 Hospitalized or died within 30 days 953 (19.0) 731 (19.8) 0.36 Data are presented as n (%) except where otherwise noted. HF, heart failure; IQR, interquartile range. ∗ Patients who died/were hospitalized before that time were excluded. † With or without primary care follow-up as well. Our findings provide reassurance that at least in Alberta, a jurisdiction where the health ministry modified billing codes on March 17, 2020, to reimburse virtual outpatient encounters (via telephone or video) at the same amount as in-person visits, there was no negative effect of the COVID-19 pandemic on promptness of follow-up for adults treated and discharged from an ED with a primary diagnosis of HF. Whether virtual outpatient encounters confer the same benefits as in-person encounters is an area of active research, with 23 , 4 of 35 studies published thus far suggesting that they do, although all 3 of these studies were of short duration and observational and thus are subject to the usual limitations of nonexperimental investigations. It should be recognized that, because our study used administrative data, we were unable to adjust for clinical confounders such as severity of HF. As such, we do not know whether patients with HF discharged from EDs during the pandemic were healthier than those discharged prepandemic: this could have happened if pandemic-era patients with advanced HF were either more likely to avoid the ED and/or more likely to contract COVID-19 and be admitted or die. Indeed, we have previously reported that during the first year of the pandemic the proportion of community dwelling Albertan adults who presented to an ED declined (from 40.1% to 34.3% for those with any ambulatory care-sensitive condition, and from 75.2% to 69.9% in those with HF).3 Moreover, although the follow-up patterns we observed were similar throughout the first year of the pandemic, whether this was maintained in the second and third years of the pandemic remains to be investigated. Whether our findings are generalizable to health systems that are less integrated (Alberta has a single government-funded health authority) or do not reimburse virtual outpatient encounters at the same rate as in-person encounters is another open research question. A third limitation is that because we only had access to data after March 2018 for this project we were unable to use the standard 5-year washout definition to designate which patients had incident vs prevalent HF. As we work to address the care deficits induced by the COVID-19 pandemic and shore up the health care deficiencies exposed by the pandemic, we need to embrace those innovations used during the pandemic that appear to have improved at least some aspects of the quality of care. To that end, we should prioritize research to investigate the efficacy and cost effectiveness of outpatient care models that balance virtual and in-person assessments. Data Sharing Statement This study was approved by the University of Alberta Health Ethics Review Board (Pro00101096), with waiver of individual patient signed consent because we analyzed deidentified health care administrative data. The data set used for this study is held securely in coded form within the Alberta Strategy for Patient Oriented Research Support Unit (AbSPORU) Data and Research Services Platform. Although legal data sharing agreements between the investigators, AbSPORU, and Alberta Health Services/Alberta Health prohibit us from making the data set publicly available, access may be granted to those who meet prespecified criteria for confidential access, available at www.absporu.ca, and sign the required Data Disclosure Agreements. Funding Sources None. Disclosures The authors have no conflicts of interest to disclose. ==== Refs References 1 Atzema C.L. Austin P.C. Yu B. Effect of early physician follow-up on mortality and subsequent hospital admissions after emergency care for heart failure: a retrospective cohort study CMAJ 190 2018 E1468 E1477 30559279 2 Hernandez A.F. Greiner M.A. Fonarow G.C. Relationship between early physician follow-up and 30-day readmission among Medicare beneficiaries hospitalized for heart failure JAMA 303 2010 1716 1722 20442387 3 McAlister F.A. Hsu Z. Dong Y. Tsuyuki R.T. van Walraven C. Bakal J. The frequency and type of outpatient visits for patients with cardiovascular ambulatory care sensitive conditions during the COVID19 pandemic and subsequent outcomes: a retrospective cohort study J Am Heart Assoc 12 2023 e027922 4 Wosik J. Clowse M.E.B. Overton R. Impact of the COVID-19 pandemic on patterns of outpatient cardiovascular care Am Heart J 231 2021 1 5 33137309 5 Yuan N. Botting P.G. Elad Y. Miller S.J. Cheng S. Ebinger J.E. Kittleson M.M. Practice patterns and patient outcomes after widespread adoption of remote heart failure care Circ Heart Fail 14 2021 e008573
PMC009xxxxxx/PMC9918809.txt	==== Front Spine Deform Spine Deform Spine Deformity 2212-134X 2212-1358 Springer International Publishing Cham 36773216 658 10.1007/s43390-023-00658-1 Case Series Incidence, etiology and time course of delays to adult spinal deformity surgery: a single-center experience DePledge Lisa 12 http://orcid.org/0000-0002-4787-1538 Louie Philip K. [email protected] 1 Drolet Cari E. 1 Shen Jesse 1 Nemani Venu M. 1 Leveque Jean-Christophe A. 1 Sethi Rajiv K. 12 1 Center for Neurosciences and Spine, Department of Neurosurgery, Virginia Mason Franciscan Health, Seattle, WA USA 2 grid.34477.33 0000000122986657 School of Medicine, University of Washington, Seattle, WA USA 11 2 2023 2023 11 4 10191026 30 8 2022 28 1 2023 © The Author(s), under exclusive licence to Scoliosis Research Society 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Purpose We sought to determine the incidence, origin, and timeframe of delays to adult spinal deformity surgery so that institutions using preoperative multidisciplinary patient assessment teams might better anticipate and address these potential delays. Methods Complex spine procedures for treatment of adult spinal deformity from 1/1/18 to 8/31/21 were identified. Procedures for infection, tumor, and urgent/emergent cases were excluded. Operations delayed due to COVID or those that were performed outside of our established perioperative care pathway were also excluded. The electronic health record was used to identify the etiology and timeline of all pre- and peri-operative delays. Results Of 235 patients scheduled for complex spine surgery, 193 met criteria for inclusion. Of these patients, 35 patients experienced a surgical delay (18.1%) with a total of 41 delays recorded. Reasons for delay include medically unoptimized (25.6%), intraoperative complication (17.9%), patient directed delay (17.9%), patient illness/injury (15.4%), scheduling complication (10.3%), insurance delay/denial (5.1%), and unknown (2.6%). Twenty-four delays experienced by 22 individuals occurred within 7 days of their scheduled surgery date. Conclusion At a single multidisciplinary center, most delays to adult spinal deformity surgery occur before a patient is admitted to the hospital, and for recommendations of additional medical workup/clearance. We suspect that the preoperative protocol might increase pre-admission delays for unoptimized patients, as the protocol is intended to ensure patients receive surgery only when they are medically ready. Further research is needed to determine the economic and system impact of delays related to a preoperative optimization protocol weighed against the reduction in adverse events these protocols can provide. Keywords Adult spinal deformity Delays Cancellations Multidisciplinary conference issue-copyright-statement© Scoliosis Research Society 2023 ==== Body pmcIntroduction Adult spinal deformity (ASD) encompasses a broad range of conditions including scoliosis, kyphosis, flatback, and other conditions that result in spinal malalignment and disability. The prevalence of ASD and the rate of complex reconstructive surgery have steadily increased in recent decades in part due to an increasing population over the age of 65 [1–3]. These complex reconstructive procedures are associated with high rates of perioperative adverse events. Subsequently, there has been a growing body of literature describing methods to mitigate these risks [4–6]. One method adopted by many healthcare systems to reduce risk and increase value is the creation of multidisciplinary teams to help manage these complex patients [7]. In 2010, the Seattle Spine Team at Virginia Mason developed a systems-based approach to minimize complication rates in surgery for ASD [8]. This three-pronged approach includes a live multidisciplinary screening conference, the use of two attending surgeons for complex cases and an intra-operative protocol for the management of coagulopathy. The live preoperative conference aim to address particular presurgical checklist items (appointments, testing, evaluation, imaging, procedures) have been completed as well as to identify modifiable comorbid medical conditions that can be optimized prior to surgery with the goal of improving overall surgical outcomes. In 2017, an analysis of this approach demonstrated a significant reduction in postoperative complications including cardiovascular events, wound infections, perioperative infections and implant failures [9]. While complication rates have decreased with this systems-based approach, surgical delays have been noted to persist by our team. Surgical delays which occur, after admission for non-elective surgical care have been shown to be negatively associated with surgical outcomes, complications, and mortality [5]. While less studied, surgical delays that occur in the days leading up to elective surgery may also have a negative effect on outcomes and can lead to inefficient use of surgeons, hospital space, and surgical staff. Elucidating the etiology of such delays provides the opportunity to anticipate and minimize these delays. This is a descriptive study investigating all delays patients experienced between the date of initial scheduling for surgery to the actual date of surgery with an emphasis on delays that occurred within 7 days of the originally scheduled surgical date. The aim of this study was to determine the etiology, incidence, and time course of all delays to adult spinal deformity surgery. To our knowledge, the incidence and etiology of delays that occur prior to complex spinal reconstructive surgery have not yet been reported in the literature. Methods Study design This study is a retrospective case series. A comprehensive list of complex spine procedures (defined as instrumentation on six or more vertebral levels) from January 2018 to August 2021 was obtained from a prospectively maintained database at a single institution. The electronic health record (EHR) was used to gather demographic information (including age, gender, ASA classification), surgical information (date of surgery (DOS), date/time of admission and discharge, operation(s) performed), medical/surgical history including any history of prior spine operations, readmissions, complications, return to the operating room (OR), use of intensive care unit (ICU), pre-operative visit history (including the number of total pre-operative encounters), and the number of times each patient was discussed at the multidisciplinary conference. Inclusion/exclusion criteria Complex spinal surgery was defined as an operation that required either 6 or more levels of vertebral fusion or more than 3 levels of vertebral fusion in a patient with multiple comorbidities [10]. All urgent/emergent cases were excluded. Elective cases were excluded if the primary diagnosis was infection or tumor/metastasis, if the procedure was delayed due to COVID, or if the procedure was performed outside of our established care pathway [8]. All patients who had documentation describing presentation at the multidisciplinary spine conference or who had preoperative workup consistent with our standard preoperative protocol were deemed to have followed the established care pathway. If there was insufficient evidence of full standard preoperative workup and/or presentation at conference, the patient was excluded from analysis (Fig. 1).Fig. 1 Flowchart demonstrating patients included in the study, divided into groups based on the category of surgical delay/cancellation Identifying delays, their etiologies, and timeframes The primary researcher identified delays by reading through all documents, notes, and messages listed in the EHR between the first encounter discussing surgery and the day surgery was performed. Confirmed surgical dates listed in the EHR were noted. Documents that most reliably listed the planned surgical date were the pre-operative clinic visit notes, anesthesia assessments, transfusion reports, PCP H&Ps, PM&R consultation documents, and most commonly, phone messages between patients, schedulers, medical assistants, advanced practice providers, and surgeons. If no conflicting dates were found, the patient was designated as proceeding without a delay. If multiple proposed surgical dates were listed, the researcher investigated reasons for the inconsistency. Any tentative date changes were not considered delays; rather, only changes to officially scheduled surgical dates were considered true surgical delays. A surgery date was considered confirmed when the surgery scheduler or a member of the preoperative surgical team (surgeons, anesthesia), documented the official surgical date. When a delay to a confirmed surgical date was identified, the researcher would determine the etiology of delay. All equivocal delays and etiologies were discussed with the surgical team to confirm or clarify the data. All reasons for delay were identified and subsequently aggregated into the following categories: additional medical workup/clearance required, intraoperative complications, patient directed delays, patient illness/injury, scheduling complications, and insurance denial/delay [9, 11, 12]. The day each delay occurred was determined by timestamps of the first relevant documentation detailing the reason for surgical delay. If no specific day could be identified, the date of delay was listed as unknown. The number of days between the date of delay and the initially scheduled date of surgery was calculated as the timeframe between delay and surgery (Table 1). The number of days between the date of delay and the date surgery was performed was also calculated (Table 2).Table 1 Timeframe between delay and initially scheduled date of surgery Reason for delay f f with unknown date of delay Mean # days between delay and DOS STDEV (days) f delays within 7 days of DOS Medically unoptimized 11 0 13.0 12.8 3 Intraoperative complication 8 0 0.0 0.0 7 Patient directed delay 7 1 21.2 27.6 3 Patient illness/injury 7 0 3.4 3.4 7 Scheduling complication 5 2 13.3 12.9 1 Insurance delay/denial 2 0 16.5 21.9 1 Unknown 1 0 7.0 N/A 1 All intraoperative delays occurred on the day of surgery, so the mean # of days between delay and DOS are 0 f frequency of delay Table 2 Turnaround time; time from date of delay to the date surgery was performed Reason Average (days) Range (days) STDEV (days) f f unknowna Medically unoptimized 118.4 4, 325 95.4 11 0 Intraoperative complication 43.8 4, 105 35.9 8 2 Patient directed delay 105.8 5, 185 70.8 7 1 Patient illness/injury 118.3 7, 386 130.1 7 0 Scheduling complication 29.7 14, 45 15.5 5 2 Insurance delay/denial 161.5 19, 304 201.5 2 0 Unknown 36.0 36, 36 0.0 1 0 af unknown = frequency of delays in which the turnaround time could not be calculated; may have been caused by an unknown date of delay or an unknown eventual date of surrey (if the even) Statistical analysis The total number, etiology, and timeframe of delays were counted and tallied manually. We used a logistic regression to examine whether the following factors significantly predicted whether a patient experienced a delay: patient sex, psychiatric history, diabetes diagnosis, age, distance from the hospital, BMI, and time measured in days (i.e., whether patient delays became more or less likely over the study time frame). This regression may represent model overfitting, and is not intended to draw definitive conclusions, but instead has been used in an attempt to describe the data. We used Fisher's exact test to examine whether experiencing one or more delays was related to ASA score. Results In total, 235 patients receiving complex spine surgery for adult spinal deformity were identified between 1/1/2018 and 8/31/2021 and 193 met our criteria. Patients were 20–84 years old (M = 64.35, SD = 21.21), over half were female (n = 116, 60.1%), the majority identified as White (n = 178, 92.2%), 84 (43.52%) had a history of psychiatric disorder, and 22 (11.4%) had been diagnosed with diabetes. Patients lived 0.3–2521.8 miles (M = 150.6, SD = 147.7) from the hospital. Surgery occurred between 19 and 1260 days from the initial consult (M = 150.6, SD = 147.7) and patients had between 1 and 56 encounters between their initial consult and surgery (M = 9.2, SD = 6.5). Most patients had an ASA score of 3 (n = 106, 54.9%), followed by 2 (n = 83, 43.0%), and 4 (n = 2, 1.0%). Out of the sample of 193 patients, 35 had a surgical delay (18.1%). The etiologies of delay, from most to least prevalent, included a need for further medical workup/clearance, intraoperative complication, patient illness/injury, patient directed delay, scheduling complication, insurance delay/denial, and unknown. The unknown reasons were those not clearly explained in the electronic medical record. Four of the 35 patients experienced multiple types of delays, so the total number of delays experienced was 41. Tables 3 and 4 demonstrates the number and frequency of patients who experienced each type of delay. The specific descriptions aggregated into each category is listed in Tables 5 and 6.Table 3 Delay incidence by category; prior to stage 1 Category n (%) % of cohort with delays Medically unoptimized 10 25.6 Intraoperative complication 7 17.9 Patient directed delay 7 17.9 Patient illness/injury 6 15.4 Scheduling complication 4 10.3 Insurance 2 5.1 Unknown 1 2.6 Percentages based on cohort of patients experiencing any delay (n = 35). Because some individuals experienced more than 1 delay, the sum of n in this table is > the total number of individuals who experienced a delay n number of patients experiencing category of delay Table 4 Delay incidence by category; between stage 1 and stage 2 Category n (%) % of cohort with delays Medically unoptimized 1 2.6 Patient illness/injury 1 2.6 Percentages based on cohort of patients experiencing any delay (n = 35) n number of patients experiencing category of delay Table 5 Specific reasons for delays by category; medically unoptimized Delay category Delay descriptions n Between stages? Medically unoptimized Nicotine use 2 No Alcohol use 1 No Opioid use 1 No Blood thinner use 1 No High BMI 1 No Low Hct 1 Yes Newfound anemia 1 No Elevated BP and A1c 1 No Another medical condition 1 No Need for further workup 1 No n number of individuals experiencing delay Table 6 Specific reasons for delays by category; logistical issues Delay category Delay descriptions f Between stages? Intraoperative complication Loss of neuromonitoring 4 No Inability to obtain LE potentials 1 No Positioning difficulties 1 No Concern for generalized tonic–clonic seizure 1 No Profound hypotension 1 No Patient directed delay Pt life circumstance 2 No Medically cleared but denied surgery due to another medical condition 2 No Denied component of preoperative pathway—psychiatric workup 1 No Desire to change surgical approach 1 No Discomfort with COVID visitor policy 1 No Patient illness/injury ED visit close to surgical date 1 No TIA 1 No Rib & pelvic fractures 1 No Cold w/ productive cough 1 No Need for cardiac workup 1 Yes DVT 1 No IVC filter placement complication 1 No Scheduling complication Surgeon availability 2 No Coordination of postoperative healthcare needs 1 No Unknown reason 2 No Insurance Delay 1 No Denial 1 No Other Other 1 No Frequency, f, is used instead of number of individuals, n, due to four individuals experiencing more than one type of delay. Thus, the frequency of delays > number of individuals experiencing a delay Of 41 total delays, there were 24 delays experienced by 22 individuals (9.8% of the patient population) within 7 days of their scheduled surgery date. Two individuals experienced two delays within 7 days of surgery (one individual experienced two delays of the same etiology, and the other had two causes for delay). Nine patients (4.7% of the patient population) experienced a surgical delay after admission to the hospital for surgery. The reasons for delay after admission include intraoperative complications (f = 8) patient illness/injury (f = 1), and medical optimization (f = 1). The timeframe by which three unique delays occurred could not be determined from the EHR. The number of days between date of delay and DOS are reported in aggregate in Tables 3 and 4. We used a logistic regression to examine whether experiencing at least one delay was predicted by any of our demographic variables (sex, psychiatric history, diabetes, age, distance from the hospital, BMI, and time), and none were found to be statistically significant. A Fisher’s exact test indicated that ASA was not significantly related to experiencing one or more surgical delays, p = 0.25. This test was run to serve as a proxy for medical complexity, as has been used in previous studies [5, 13, 14]. Discussion Our institutional preoperative workflow with a multidisciplinary patient assessment team has been shown to improve outcomes for patients undergoing surgery for adult spinal deformity [8, 9]. However, surgical delays remain a roadblock to optimal surgical outcomes and potentially hospital resource utilization [14]. In this study, we meticulously investigated the preoperative workup of 235 patients and detailed exactly why surgical delays occurred in our institution. Incidence and etiology Our incidence of delay to surgery was 18.1%. This included delays occurring prior to hospital admission (13.4%) as well as those occurring after admission for surgery (4.7%). One multi-center study investigating the incidence of surgical delays for adult spinal deformity and reported an incidence of delay to surgery of 15.6%, although this study only assessed delays that occurred after admission to the hospital for surgery and used the ACS-NSQIP database which limited the ability to identify the etiology of the delay. Our post-admission delays affected a much lower percentage (4.7%) of our surgical population, which may represent one advantage of the extensive pre-surgical evaluation our patients undergo, but direct comparison of the cause of delays in our population and those within the Wade et al. study is not possible [5]. Given that those authors reported worse outcomes associated with delays after hospital admission, we propose that shifting any delay from a post-admission one to a pre-admission one may be a worthy price to pay in the pursuit of reduced delays after hospital admission and their worsened surgical outcomes [8, 9]. Recent literature that similarly investigates the incidence of surgical delays generally focuses on the risk factors and outcomes of surgical delays without detailing the cause for such delays [5, 13, 14]. In our study, we found that the most common etiology of a delay was a need for further medical workup and/or clearance. Because our multidisciplinary optimization pathway is designed to only allow surgery once a thorough medical evaluation has been completed, it was not surprising that the most common etiology of delay was need for additional medical workup, typically entailing cardiac workup via stress test or pulmonary evaluation via pulmonary function tests. Because these delays presumably prevent operations from occurring before patients are medically ready, it may not be necessary to minimize this etiology of delay, but to acknowledge that they may increase the amount of time that should be allotted between an initial surgical evaluation and a proposed surgical date. However, of 11 delays that occurred due to need for further medical workup, 3 occurred within 7 days of the scheduled surgery date. These specific instances include: continued use of nicotine, use of a blood thinner, and newfound anemia. Delays this close to the surgical date are more likely to lead to underutilized OR time and staff that could have otherwise been dedicated to another patient. Given this drawback, situations resulting in delay close to the surgical data should be avoided if possible. Describing delays: avoidable or inevitable? To improve the preoperative workflow, we thought it important to identify avoidable delays. In an effort to categorize, we deemed that delays may be avoidable, inevitable, or those that could be either depending on the circumstance. Delays that are inevitable are the most intuitive to identify. There will always be a baseline rate of events that occur outside a patient or hospital’s control, such as motor vehicle accidents or family emergencies. Delays that are avoidable are generally secondary to factors within patients’ or the surgical team’s control, such as scheduling complications, communications with insurance companies, and timely assessment and treatment of medical conditions. While the EHR was vague in terms of the details of insurance delay or denial, in our experience, these occur due to lack of clarity in clinical documentation, paperwork processing delays in the setting of short staffing, description of radiographic results, and communication barriers between clinical team and insurance company. We deem that this category of delay has the potential to be avoided. Delays secondary to modifiable factors discussed in preoperative appointments are not as straightforward (Table 2). Within this category, specific to instances where additional medical workup/clearance was recommended, we have identified two reasons why delays might occur: (1) the need for a change (lowering BMI, cessation of tobacco/alcohol/opioids, etc.) was not appropriately emphasized in preoperative discussions, or (2) the required medical change was unrealistic for the patient to achieve within the available time frame (i.e. inability to wean opiates/tobacco/alcohol, weight loss, etc.). Because it is common practice to discuss all additional medical workup/clearance needs with multiple providers, we suspect that reason 2 is a more likely culprit for delays due to need for additional medical workup/clearance particularly for those that occur within 7 days of scheduled surgery. In light of this, we recommend that providers spend time discussing what changes are realistic for patients, and if a necessary change is deemed difficult, to have frequent follow up to assess for progress well in advance of the scheduled surgical date. Finally, there is a category of delay that may or may not be avoidable, such as due to new, concerning lab values (additional medical workup/clearance recommended) or intraoperative positioning difficulties (intraoperative delay). Using newfound anemia as an example; it is the case that this finding may not have been detected early enough to have made the necessary change to make the patient medically ready for surgery. Alternatively, it could be the case that this anemia was not present until soon before surgery, and thus would be an inevitable delay. Similarly, positioning difficulties may have been detectable in the office through discussing the patient’s position during surgery, or it may have been unrealistic to practice such positioning in the clinic. While many delays will fall within this gray zone of having the potential to be either avoidable or inevitable, we believe that awareness of etiologies of delays will allow ours and similar systems to better anticipate and mitigate the impact of such delays. Based on our surgical team’s observations, we hypothesize that delays that occur within 7 days of the scheduled surgical date commonly result in open schedules for ORs and underutilized surgical staff. Intraoperative delays and patient illness/injury were most commonly responsible for delays to surgery within 1 week of scheduled surgery date (Table 1). We suspect that these delays were unpredictable and could not have been avoided with additional medical workup/clearance. Further research is needed to determine how these delays impact complications and costs for both the patient and the hospital. Should these delays prove a significant impact on outcomes and hospital costs, methods to mitigate the impact of these delays should be investigated. Limitations Although the COVID-19 pandemic did not change the preoperative workflow for patients with adult spinal deformity, it may have impacted which surgical cases were attempted. On one hand, surgeons may have preferentially attempted cases that were less likely to experience complications, delays, and need postoperative intensive care. On the other hand, it is possible that only the most severe cases that could not wait until after the pandemic were prioritized. COVID-19 protocol went into effect on March 14, 2020, but surgical delays were no more likely to occur earlier compared to later in the study time period. Lastly, this was a single-center review of a standardized multidisciplinary team and may not be representative of all spine centers. Conclusions In a multidisciplinary spine care system, preoperative medical evaluation reduces the incidence of delays to surgery after hospital admission compared to prior reports. The most common etiology of delay was the recommendation of additional medical workup/clearance and peri-operative medical complications. Delays for additional medical workup may not need to be avoided, and inevitable delays should be expected at tertiary or quaternary centers that employ multidisciplinary processes to optimize patients. However, from the patient perspective, these delays result in prolonged disability from their spinal deformity and can be an inconvenience to the patient and their caregivers. Because neither delays due to intraoperative complications nor illness/injury can be predicted, we suspect that these delays are inevitable, and any system employing a multidisciplinary protocol for adult spinal deformity surgery should anticipate a baseline incidence of inevitable delays. A subset of seemingly inevitable delays occurs within 7 days of surgery date, and additional research is needed to determine the medical and financial impact of such delays. Finally, many delays have the capacity to be either avoidable or inevitable, and by being aware of the etiologies of delays, multidisciplinary teams may hone their focus in the attempt to minimize the incidence of delays, particularly within 7 days of surgery. Surgical teams should rigorously build teams that support and standardize the preoperative medical optimization of patients undergoing spinal reconstruction for ASD. To the authors’ knowledge, this is the first study to outline the incidence, etiologies, and time course of surgical delays in spinal deformity surgery. Author contributions Data collection: Depledge, Louie, Drolet, Shen, Nemani, Leveque, Sethi. Writing–original draft preparation: Depledge, Louie, Drolet, Shen. Approval of final version of manuscript: Depledge, Louie, Drolet, Shen, Nemani, Leveque, Sethi. Agree to be accountable for the work: Depledge, Louie, Drolet, Shen, Nemani, Leveque, Sethi. Funding No funding was obtained for this study. Data availability All data is available upon request. Declarations Conflict of interest The authors have no conflicts of interest to disclose directly related to the content of this manuscript. Ethical approval IRB 21-004. Informed consent Per our IRB office, informed consent was not applicable for this study. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Diebo BG Shah NV Boachie-Adjei O Zhu F Rothenfluh DA Paulino CB Schwab FJ Lafage V Adult spinal deformity Lancet 2019 10.1016/S0140-6736(19)31125-0 31305254 2. Lutz W Sanderson W Scherbov S The coming acceleration of global population ageing Nature 2008 10.1038/nature06516 18362917 3. Fehlings MG Tetreault L Nater A Choma T Harrop J Mroz T Santaguida C Smith JS The aging of the global population Neurosurgery 2015 10.1227/NEU.0000000000000953 26378361 4. Friedman GN Benton JA Echt M De la Garza RR Shin JH Coumans J-VCE Gitkind AI Yassari R Leveque J-C Sethi RK Yanamadala V Multidisciplinary approaches to complication reduction in complex spine surgery: a systematic review Spine J 2020 10.1016/j.spinee.2020.04.008 32325247 5. Wade SM Fredericks DR Elsenbeck MJ Morrissey PB Sebastian AS Kaye ID Butler JS Wagner SC The incidence, risk factors, and complications associated with surgical delay in multilevel fusion for adult spinal deformity Glob Spine J 2022 10.1177/2192568220954395 6. Shuman WH Neifert SN Gal JS Martini ML Schupper AJ Steinberger JM Maron SZ Lamb CD Rothrock RJ McNeill IT Cho SK Caridi JM Adult spinal deformity surgery: the effect of surgical start time on patient outcomes and cost of care Spine Deform 2020 10.1007/s43390-020-00129-x 33006745 7. Frimpong JA, Myers CG, Sutcliffe KM, Lu-myers Y (2017) When health care providers look at problems from multiple perspectives, patients benefit. Harv Bus Rev 8. Sethi RK Pong RP Leveque J-C Dean TC Olivar SJ Rupp SM The Seattle spine team approach to adult deformity surgery: a systems-based approach to perioperative care and subsequent reduction in perioperative complication rates Spine Deform 2014 10.1016/j.jspd.2013.12.002 27927385 9. Sethi R Buchlak QD Yanamadala V Anderson ML Baldwin EA Mecklenburg RS Leveque JC Edwards AM Shea M Ross L Wernli KJ A systematic multidisciplinary initiative for reducing the risk of complications in adult scoliosis surgery J Neurosurg Spine 2017 10.3171/2016.11.SPINE16537 28362214 10. Halpin RJ Sugrue PA Gould RW Kallas PG Schafer MF Ondra SL Koski TR Standardizing care for high-risk patients in spine surgery: the Northwestern high-risk spine protocol Spine (Phila Pa 1976) 2010 10.1097/BRS.0b013e3181e8abb0 21102298 11. Sethi RK Burton DC Wright AK Lenke LG Cerpa M Kelly MP Daniels AH Ames CP Klineberg EO Mundis GM Bess S Hart RA The role of potentially modifiable factors in a standard work protocol to decrease complications in adult spinal deformity surgery: a systematic review, part 2 Spine Deform 2019 10.1016/j.jspd.2019.03.001 31495467 12. Sethi RK Yanamadala V Shah SA Fletcher ND Flynn J Lafage V Schwab F Heffernan M DeKleuver M Mcleod L Leveque JC Vitale M Improving complex pediatric and adult spine care while embracing the value equation Spine Deform 2019 10.1016/j.jspd.2018.08.006 31495467 13. Renfree SP Makovicka JL Chung AS Risk factors for delay in surgery for patients undergoing elective anterior cervical discectomy and fusion J Spine Surg 2019 10.21037/jss.2019.10.09 32042998 14. Wagner SC Butler JS Kaye ID Sebastian AS Morrissey PB Kepler CK Risk factors for and complications after surgical delay in elective single-level lumbar fusion Spine (Phila Pa 1976) 2018 10.1097/BRS.0000000000002282 28604494
PMC009xxxxxx/PMC9919740.txt	==== Front Crime Law Soc Change Crime Law Soc Change Crime, Law, and Social Change 0925-4994 1573-0751 Springer Netherlands Dordrecht 36815947 10080 10.1007/s10611-023-10080-3 Article “This is where I belong:” a narrative study of professional commitment to a new criminal justice agency http://orcid.org/0000-0002-2736-0829 Arriagada Isabel [email protected] grid.17635.36 0000000419368657 Department of Sociology, University of Minnesota, Minneapolis, MN USA 11 2 2023 2023 79 5 505530 18 1 2023 © The Author(s), under exclusive licence to Springer Nature B.V. 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Scholars of penal change have established a rich theoretical understanding of the macro- and meso- level processes that explain the emergence, diffusion, and success of penal developments. Similarly enthusiastic examinations of the agentic aspects of professional commitment to criminal justice institutions are necessary to better understand the relationship between micro-level individual processes and the endurance and success of penal projects. The present study builds on existing analyses of cause lawyering and indigent criminal defense to examine the personal narratives of penitentiary defenders, lawyers working for the Unit of Penitentiary Defense, a novel Chilean public agency that offers legal assistance and enables convicted prisoners to file grievances and report rights violations before criminal courts. By drawing on 45 in-depth semi-structured interviews, I analyze the ways in which these attorneys incorporate biographical experiences and life events into coherent stories that both support and construct their professional identity as legal aid lawyers despite adverse working conditions. Four narratives are prevalent in their accounts: identification, privilege, calling, and admiration. These narratives demonstrate that criminal justice professionals engage in meaning-making processes through the creation of biographical accounts that tie personal and professional self-understandings together. The contribution of the article is thus twofold: it situates the role of individual agency in the development of penal projects and provides a novel explanation as to how legal aid lawyers become personally and professionally invested in indigent defense. Keywords Work motivation Professional identity Narrative criminology Public Defense Latin America Criminal Justice issue-copyright-statement© Springer Nature B.V. 2023 ==== Body pmcIntroduction Over the past decade, several Latin American countries have reformed their criminal justice systems. These reforms have entailed vast institutional changes including the installation of new public agencies, such as the National Public Defender’s and the National Prosecutor’s Offices. Reforms of this type represent the most profound transformation that Latin American criminal justice systems have undergone in nearly two centuries (Hilbink, 2007; Langer, 2007). Significantly, these agencies require a critical mass of criminal justice professionals who are committed to ensuring these new criminal justice institutions endure and succeed over time. Scholars of penal change have established a rich theoretical understanding of the social, political, and historical forces that explain the advancement of penal projects – such as legal reforms and the establishment of new institutional capacities (Garland, 2013). Comparative empirical studies address how nation-specific arrangements – such as electoral and party systems, bureaucratic structures, and mechanisms of knowledge production – explain the configuration of penal systems across societies (Lacey, 2008; Lappi-Seppälä, 2011; Savelsberg, 1994; Tonry, 2009). Sociolegal studies have also begun to explore the contingent political struggles that take place in local policy sites to explain the shape and scope of penal institutions in specific times and places (Goodman et al., 2017; Loader & Sparks, 2004: 16; Page, 2012; Rubin, 2015). While these macro- and meso- approaches have proven fundamental for understanding the emergence, diffusion, and success of penal projects, similarly enthusiastic examinations of the agentic aspects of professional commitment to criminal justice institutions are necessary to better understand the relationship between individual agency and the success and endurance of penal change. Large-scale social phenomena matter in the configuration and development of penal systems; however, “people make them matter in particular ways” (Goodman et al., 2017: 123 − 24). Penal scholars have used different micro-level individual approaches to explore the ways in which criminal justice professionals and penal practitioners – lawyers, social workers, judges, educators, parole agents, correctional officers – join, remain committed, or abandon penal projects. Sociolegal studies in cause lawyering and indigent criminal defense have been particularly prolific in this regard. Research on law students and lawyers provide different co-occurring individual-level explanations of attorneys’ preferences to work as criminal defense lawyers, including altruistic personality traits, the allure of the material benefits involved in legal practice, and the individual’s position in the social structure (Baćak et al., 2020; Curran & Noone, 2007: 78, Emmelman, 1993; Etienne, 2004; McIntyre, 1987, Menkel-Meadow, 1998). Whereas traditional approaches rely on personal qualities, rational calculations, and structural explanations of professional commitment, alternative theories suggest paying attention to the complex agentic aspects of professional identity construction. Researchers in adjacent fields of study –such as social psychology, administrative sciences, organizational studies, and narrative criminology– have begun to pay attention to the ways in which individuals themselves engage in self-defining processes of professional identity construction. The narrative study of lives has contributed greatly to the understanding of how professionals find sense and meaning from interpreting life events in their biographies as the basis for their professional engagement to organizations and institutions (McAdams et al., 1997; Bloom et al., 2021; Bunderson & Thompson, 2009). The present study builds on existing analyses of criminal defense lawyers’ professional commitment by applying a narrative framework to the case study of penitentiary defenders (hereinafter, defensores1), Chilean lawyers who work for the Unit of Penitentiary Defense (hereinafter, the UPD), a relatively new agency that provides legal assistance and enables convicted prisoners to file grievances and report rights violations before criminal courts. Drawing on 45 interviews with 37 defensores, I examine the ways in which public attorneys in the Chilean criminal justice system incorporate biographical experiences and life events into coherent narratives that support and justify their professional roles. Findings reveal that defensores use four main narratives as explanations for their professional commitment to criminal defense. One narrative type addresses defensores’ first-hand interactions with the justice system in the past. Since some have experienced the vicissitudes of the justice system from a very young age ––usually because of relatives’ involvement in criminal activities –– a group of defensores rely on narratives in which they identify themselves with the population they serve (narratives of identification). A second narrative type refers to childhood experiences of social privilege and economic wellbeing as foundations for defensores’ need to give back to society. This narrative type reveals that some defensores understand their past as a source of social indebtedness to marginalized populations (narratives of privilege). A third narrative type, narratives of calling, occurs when defensores refer to different life scenarios ––beginning in childhood and adolescence–– where they demonstrate having the abilities to engage in advocacy and social justice endeavors. These narratives are presented as cohesive life stories that attest that defensores have always had the skills and motivation needed to be a good defensor. The fourth and final narrative type takes place when defensores revere the meaningful relationships they had with mentors in the past –such as primary teachers, grandparents, or law school professors– and present their current professional practice as a way of honoring the values, principles, and ideals put forward by these early role models (narratives of admiration). Furthermore, these narratives do not occur in a vacuum: they are produced under broader large-scale historical trends that have taken place in Chile over the past decades. The contribution of the article is thus twofold. First, it contributes to the broader literature of punishment and society studies by situating the role of individual agency in the configuration, development, and success of penal projects. Second, the article contributes to the criminal indigent defense literature –and the literature of professional narratives more broadly– by explaining how legal aid lawyers become personally and professionally invested in agencies within the criminal justice system. It shows how professionals in a criminal justice agency engage in meaning-making processes through the creation of biographical narratives that tie personal and professional self-understandings together. In sum, this study incorporates a narrative perspective of personal commitment to professional work in criminal justice institutions and thus contributes to new understandings about the ways in which individuals become involved in penal projects. It shows how penal practitioners undertake a narrative reconstruction of their biographical experiences that allows them to make sense of their professional commitment to the provision of legal aid within the criminal justice system. In doing so, it takes a deeper look at the institutional development of the criminal justice system from the perspective of individuals who inhabit it. Examining how individuals interpret their pasts ––the memories they recall, the life scenes they recount, the milestones they celebrate, and the plot lines they put together –– is important for identifying how and why some pathways lead to personal and professional stories of commitment (McAdams et al., 1997). The personal biographies and life narratives of actors in criminal justice agencies such as the UPD can strengthen current understandings of penal change. In terms of structure, the next section of the article describes the legal practice of indigent criminal defense, discusses the strengths and weaknesses of dominant theories of criminal defense attorneys’ professional commitment, and outlines key features of narrative theory. The subsequent section presents the case of the Unit of Penitentiary Defense (UPD), its origins, background, and the current challenges that defensores encounter in their daily practice. I then describe the data and methods. The findings section describes the four types of narratives that defensores resort to in order to make sense of their personal commitment to their professional identities. The final section discusses the theoretical contribution and the value of exploring professional commitment from a narrative perspective in criminal justice research. Indigent criminal defense: dominant explanations and narrative theory A fundamental component of modern criminal justice systems is the provision of indigent defense, i.e., the protection of the legal rights of those accused of breaking the law who cannot afford their own attorney (Baćak et al., 2020). Both Anglo-Saxon and Latin American scholarship reveal that, while a necessary part of functional legal systems, public defenders encounter numerous challenges. Client turnover, engagement in multiple cases, and the lack of attention from judges and courts causes the routinization of lawyers’ tasks and undermines their ability to adequately perform their duties (Emmelman, 1993; Etienne, 2004: 1244; Libedinsky, 2015; Norton et al., 2015; Stippel et al., 2020; Venegas, 2018; Zaloznaya & Nielsen, 2011: 920). Adverse working conditions can undermine lawyers’ commitment to the profession and render the provision of legal services for vulnerable populations a dull, frustrating, and exhausting experience. However, despite these multiple challenges, many attorneys decide to accept these conditions and work as legal aid professionals (Baćak et al., 2020; Curran & Noone, 2007: 78, Emmelman, 1993; Etienne, 2004; McIntyre, 1987). Studies of criminal and indigent defense lawyers provide different explanations of this professional commitment. First, some attribute cause lawyers and criminal defenders’ commitment to legal aid to a “social justice personality” and psychological dispositions to caring labor that prompts them to engage in self-sacrificing behaviors for the benefit of others. Second, rational choice theorists explain engagement in public defense as the result of a cognitive assessment of the benefits and costs involved in the practice, including monetary rewards and other tangible benefits. Lawyers assess the “market-value” of their capacities and aptitudes to maximize the profit out of the possible opportunities within their reach. Finally, structural explanations ascribe personal commitment to individual positions within the social structure in terms of class, race, and gender. They usually point to the capacity of lawyers that come from underprivileged backgrounds to develop more empathetic dispositions towards marginalized populations (Baćak et al., 2020; Etienne, 2004; Menkel-Meadow, 1998). These traditional explanations provide valuable knowledge about the possible factors that sustain legal aid lawyers’ commitment to indigent defense, but some important elements are missing. First, explanations based on personality traits often overlook the power of social forces in shaping and changing individual’s social lives (Dannefer et al., 2016: 88–89; Thorne, 2004: 365). Second, the cognitive perspective of decision-making assumes that individuals are rational calculators who are free to choose their professional careers. They also present us with a false dichotomy between material and ideal modes of action and overlook the fact that individuals can be driven by both tangible and intangible rewards (Somers, 1994). Finally, structural explanations derive the meaning of action from “totalizing fictions” in which fixed categories of experience (such as race, class, and gender) over-determine actors’ decisions (Somers, 1994: 610 − 11). A universalistic framework like this reifies essentialist categories (like being Black or female) and would not explain other (more profitable) career choices of non-privileged non-white female lawyers that are not motivated by engagement to a social cause. To further understand how individuals participate in the advancement and development of penal projects, it is crucial to examine how they themselves construct their personal biographies around their professional roles. To date, these processes of professional identity construction as explanations of commitment to criminal justice defense are absent from the majority of these accounts. Narrative theory has become a crucial methodology in the exploration of processes of professional commitment. One of the core issues of the modern idea of personal identity is based upon on the notion that individuals are active participants of their own self-construction; they revise their personal past, examine the present, and foresee the future in terms of an integrative narrative of self that gives unity and purpose to their lives (Bruner, 1991; Giddens, 1991; Mead, 1934). Narrativists have coined the terms “Homo Narrans” and “Homo Fabulans” to highlight the readiness of the human species for the narrative organization of experience (Czarniawska, 2004; Fischer, 1987). Narratives — in the form of legends, history, fables, or conversation — are the medium through which humans construct, recall, and organize their experiences and memories of reality (Bruner, 1991). Narratives can reveal both the socio-structural components that condition material existence —such as historical, cultural, and economic forces — but also the biographical, full-fledged, reflective, plastic, and creative nature of the human mind (Mead, 1934). In the modern world, professional identity has become a defining trait of the self and its everyday action (Ashforth & Schinoff, 2016; Bunderson & Thompson, 2009; Fine, 1996). Professions and professional organizations, such as the workplace, offer a structure by which individuals define their work and identity in order to address a central question: ‘What kind of person am I?’ (Ashforth & Schinoff, 2016; Fine, 1996; Ibarra, 1999; Ibarra & Barbulescu, 2010; van Hulst & Ybema, 2020). Narrative studies examine the ways in which professionals incorporate biographical experiences and life events into coherent narratives that support and justify their professional roles (Bloom et al., 2021; Bunderson & Thompson, 2009; Christiansen, 1999; McAdams et al., 1997). These studies describe the different type of stories professionals tell about themselves. For instance, expert narrativist and social psychologist Dan McAdams coined the term “generative stories” to describe personal accounts in which narrators enjoy an early family blessing, are sensitive to the suffering of others at an early age, and set personal goals for the future to benefit society (McAdams et al., 1997; McAdams, 2001; McAdams & Bauer, 2004). Generativity can be found in a vast array of life pursuits, including professional activities and volunteer endeavors (McAdams & de St. Aubin, 1992: 1003). Similarly, Bloom et al. discovered that many “called” professionals, such as social aid workers, pastors, physicians, and teachers engage in processes of self-discovery to create a “narrative of discernment” where they realize that their unique talents and aptitudes preceded and somehow anticipated their destiny of dedicating themselves to caregiving professions (Bloom et al., 2021: 312, similarly, Swen, 2020). The stories professionals build to tie their personal biographies to their professional roles help narrators not only generate consistency and stability in their sense of self but also help them explain their competence for their professional practice (McAdams & Guo, 2015). Yet to date, few studies on professional commitment to criminal justice institutions have applied a narrative framework to personal processes of professional identity construction. The unit of penitentiary defense: origins, background, and challenges This research examines the Chilean Unit of Penitentiary Defense, a relatively new institution in the Chilean criminal justice system (established in 2009), as a case study for the exploration of professional narratives in criminal indigent defense. Outraged by the precarious conditions of Chilean prisons, a group of penal experts, public defenders and a specialized team of social workers developed an interdisciplinary project to assist convicted prisoners make legal claims and report situations of abuse against prison authorities (Libedinsky, 2015). At the time, the living conditions of the more than 46,000 prisoners in Chile were (and continue to be) precarious and inhumane. In 2008, a report described the existence of torture, cruel treatment, and degrading conditions along with inadequate access to drinking water, food, education, and medical services in Chilean prison facilities (Universidad Diego Portales, 2008: 77). Allied with the Spanish Agency for International Development Cooperation, a team of professionals created the Unit of Penitentiary Defense (UPD) and instituted the role of the penitentiary defender (defensor). Unlike regular public defenders —lawyers who protect the rights of individuals accused of crimes during a criminal investigation — penitentiary defenders provide indigent defense and initiate administrative and judicial action to protect convicted prisoners’ constitutional rights while serving their sentences (Libedinsky, 2015; Stippel et al., 2020; Venegas, 2018).2 Institutional equivalents of the UPD can be found in Australia (Prison Advice Center from the Legal Services Commission), Argentina (Defensoría General de la Nación), and Ecuador (Defensoría Pública).3 With the new UPD and its contingent of defensores, convicted prisoners gained, for the first time, post-sentencing access to public legal assistance (Libedinsky, 2015). The program currently has 54 defensores working across the country’s entire 16 regions (Stippel et al., 2020). Important sociopolitical factors gave way to the institutionalization of the UPD. In the year 2000, the Chilean government implemented a criminal justice reform, widely known as the “Reforma Procesal Penal.” The Reforma was the result of two large-scale phenomena; first, a political movement aimed at strengthening the rule of law and human rights protections after the legacy of Pinochet’s authoritarian regime, and second, increased demands for effective criminal prosecution (Hathazy, 2016; Wilenmann, 2020). The Reforma entailed vast public investments in new infrastructure and employment opportunities and thus gave way to a massive new state bureaucracy (Wilenmann, 2020, in Argentina similarly: Bergoglio, 2009), which recruited a new emergent class of criminal justice professionals. Another important factor is the Supreme Decree of 1981 which allowed for the creation of private universities. This in turn gave middle-class and first-generation students greater access to higher education (Chacón, 2015; Villalonga, 2021). Between 1982 and 1993, 25 new law schools were established in both public and private universities. By 2014, there were 49 law schools in Chile (Villalonga, 2021). The expansion of higher education enrollment, the proliferation of private law schools, and the growing participation of groups traditionally excluded from liberal professions contributed to the diversification of the social origins and demographics of law students (Villalonga, 2021: 414) as well as the expansion of an available workforce for civil service (similarly, Bergoglio, 2009). A final factor is linked to far-reaching restructuring attempts of the Chilean public sector which took place in the wake of Pinochet’s dictatorship. This restructuring primarily sought to outsource a wide range of tasks and services and establish the adoption of market-type employment mechanisms (Herrera et al., 2020; Mori, 2020), which has given way to a so-called mixed defense system, where the state employs different forms of public tenders in which private practitioners (in this case, defensores) bid to offer legal aid at the lowest cost (Stippel et al., 2020; Villalonga, 2021). This public-private system offers defensores a middle-range competitive salary for the Chilean job market (± U$2,000 monthly), not comparable with high wages from top law firms, but analogous to the remuneration from other similar white-collar jobs in the public system. Reformist projects, the expansion of job opportunities, access to higher education, and flexible government contracts have given way to greater access to legal services to marginalized populations (Bergoglio, 2009: 22–23) and also provide emergent legal professionals with ample work opportunities. As state officials, the work of defensores presents many challenges. They are exposed to the traditional restrictions of public bureaucracies and must fight against the precarity of the Chilean prison system. They work with limited resources, staff shortages, as well as emotionally exhausting encounters with state clients. Note that there is only one defensor per 1,000 prisoners (Stippel et al., 2020). Moreover, correctional authorities have resisted the presence of defensores in prison facilities (Libedinsky, 2015: 237) and a predominant sector in the Chilean judiciary has proven to be skeptical of legal claims regarding prisoners’ constitutional rights (Libedinsky, 2015; Venegas, 2018). High caseloads, institutional resistance, and adverse work conditions threatens defensores’ motivation to remain on the job. Therefore, the puzzle remains: Why do defensores decide to commit themselves to work in indigent defense? Data and methods Data in this study come from in-depth interviews with 37 defensores undertaken between December 2019 and November 2021. Interviews lasted on average 60–70 min and were audio recorded (with participants’ permission) and transcribed. Only the quotes used in this paper were translated into English.4 I refer to participants by pseudonyms and have removed or slightly changed identifying information. During the period from December 2019- February 2020 I conducted seven in-person interviews and managed to establish good rapport with my interviewees. However, due to the COVID-19 pandemic, my in-person fieldwork was brought to a halt in March of 2020. I adjusted my methodological approach and begun to conduct interviews via telephone and video communication (through Zoom, a video communication platform). I also began to sustain constant communication with many of my interviewees through a free instant messaging application (WhatsApp). The use of the video platforms and text messages reconfigured my fieldwork and increased my research access instead of decreasing it (see also: Ndhlovu, 2021). For instance, before COVID-19, clarifying or expanding on some points of the interviews was unlikely or unrealistic once they had been conducted. Unless I scheduled a new interview, interviewees would consider their interaction with me to be restricted to the specific time and place where the interview was carried out. After the COVID-19 pandemic began, I was able to request clarifications via email or WhatsApp messages. Defensores themselves would text me or send audio messages to clarify their points, send me new information, or expand on subjects of their interest. The interviews were semi-structured and organized as life-story interviews, covering participants’ lives from childhood to the present. By November 2021, I had interviewed 28 current defensores, 9 former defensores (Interviewees = 37), and conducted 8 follow-up interviews with defensores with whom I established good rapport (Interviews = 45).5 The majority of the interviews took place during the pandemic, which makes it difficult to capture any substantive difference in professional narratives pre- and post-COVID. The sample of defensores consists of 21 women and 16 men, with a mean age of 36 years old. Many of these defensores are first-generation college students (N = 17) or middle-class (N = 20) students that come from second or third tier law schools (N = 32). All 9 of the former defensores in the sample had secured jobs in private or public legal practice after leaving the Unit. In the interviews, I aimed to elicit detailed life stories and inquire into defensores’ personal and professional lives. I included questions focused on personal and family backgrounds, education, law school training and graduate studies, and their understandings of professionalism. Questions about their current routine as defensores revolved around their everyday work duties and workload, their perceived skills, milestones or significant career experiences, and relationships with colleagues and clients. I did not begin the interview processes with a focus on the connection between personal stories and professional narratives. Initial comments indicating a sense of connection between defensores’ personal pasts and professional presents shifted the focus of the ensuing interviews. It became apparent that if I sought to fully grasp defensores’ understanding of their profession, the interview questionnaire needed to delve deeper into their view of themselves, their pasts, their families, their values, and other moments of introspection. Most of the interviewees were eager to discuss their personal and professional lives and I was thus able to obtain large amounts of data on both their personal experiences as well as their general ideas of penitentiary defense. As a Chilean lawyer myself, I have the advantage of understanding the inner workings and decision-making practices of the prison field, cultural expectations about the legal profession, and knowledge of juridical jargon. I used an open and axial coding scheme with NVivo 12 to identify emergent categories from the interviews. In examining these data, I took a grounded theory approach (Glaser & Strauss, 2017), which allows the researcher to inductively develop theory from fieldwork in a flexible, yet systematic way, which is especially useful in social justice inquiry (Charmaz, 1999). The interviews were analyzed as storied psychosocial constructions rather than as veridical reports of the past (McAdams et al., 1997). I first read through all the interviews and sorted comments into an emergent set of topical categories. Those comments reflecting a belief that being a defensor was “something that one was meant to be or part of who one has always been” emerged as the most frequently coded category in the data, in 29 out of 37 interviewees (close to 80%). Sample comments included “I knew this is what I was meant to do,” “I see prisoners and I see my family,” “This is where I belong,” and “I can’t see myself working anywhere else.” After several iterations through the entire set of interviews, I reached a point of saturation at which I developed autonomous categories for relevant excerpts. The second round of coding and in-depth analysis focused on how defensores narrate their past and connect it to their present. As common themes began to emerge, I resorted to studies on public defense, cause lawyering, public administration, and narrative analysis. Narrative theory offered a powerful toolkit to analyze life scenes, plots, characters, and linguistic resources (Bruner, 1991; McAdams et al., 1997; McAdams, 2001; McAdams & Guo, 2015; McLean et al., 2007; Somers, 1994; Thorne, 2004). Studies on narrative criminology (Fleetwood et al., 2019; Presser, 2016; Ugelvik, 2016; van Hulst, 2013) and work as a calling in administrative sciences also offered a strong theoretical precedent to explain preliminary findings (Bunderson & Thompson, 2009; Bloom et al., 2021). The end result was an articulation of the different life scenes, inner dialogues, and reflections presented by defensores of the ways in which the criminal justice system is narrativized and becomes embedded in their personal accounts. As I coded the interviews, four themes emerged as crucial elements of interpretation: identification, privilege, calling, and admiration. A summary of these categories is presented in Table 1. Table 1 Narrative categories and sample quotes Type of narrative Content Sample quote Identification Mentions first-hand experiences with the Chilean criminal justice system prior to becoming a defensor. Includes references to pasts of precarity and marginalization. I think that that [my parents’ imprisonment] has helped me to develop a skill, a particular sensitivity in my job that is different than [others]. Privilege Associates pasts of affluence/wellbeing with contemporary commitment to public service. Includes references to a sense of responsibility, desire to give back to society, and sensitivity to the suffering of others. I always say to my dad that we have had many privileges in life; even up until today. […] From that position of privilege, we can do great things too. Calling Defensores highlight their personal aptitudes to fulfill their professional roles. Narratives explain how distinctive characteristics preceded and somehow predicted the decision to join the profession. Includes references to processes of self-discovery as well as notions of duty, fate, and destiny. My dad would always say to me ‘Hey, you’re going to be a lawyer’. Maybe that stuck with me since I was little and over time it increased. […] At the time I had to choose a career I said ’Ok. I’ll go to law school’. That was kind of a surprise for everyone, except for my parents. They said that they knew I was going to enter law school. Admiration References to role models in early childhood, adolescence, and young adulthood connected to empathy with marginalized populations and the exercise of criminal defense. Rodrigo was key. Key. Key. Key. […] He taught us the core values of law. Today I feel that being a defensor is letting me do something with the core principles that I learned in those years. I coded as “Identification” those comments highlighting the importance of interviewees’ first-hand experiences with the Chilean criminal justice system prior to becoming a defensor, including testimonies of marginalization, crime involvement, and visits to criminal justice agencies such as criminal courts and penal facilities. This code also comprises references to how these past experiences of institutional contact shaped defensores’ current sense of aptitude and professionalism. I used the label “Privilege” to code excerpts where defensores mention their privileges and past affluence of both themselves and of their families manifested in accessing exclusive services activities (such as attending a private school or traveling) and purchasing upscale goods. Under this category defensores compare their past and prosperous living situation in the present with that of convicted prisoners and the moral duty that emerges consequently. I coded as “Calling” defensores’ interpretations of past events that demonstrate early personality traits and dispositions towards justice that make these defensores particularly suitable for their job. It also refers to premonitions that indicated a future in lawyering. Finally, I coded as “Admiration” narratives of role models who defensores’ report to have had an impact on their lives. It includes references to family members, significant adults, mentors, or university professors that provide an image of kindness, knowledge, enthusiasm, or aptitude for public service. This coding scheme is not mutually exclusive. Comments could be attached to one or several mother codes. Findings Throughout the interviews, defensores shared a narrative interpretation of experiences prior to the acquisition of their professional roles, which I argue helps them establish a connection between their personal lives –including their childhoods, family backgrounds, events in adolescence, and college experiences– and their commitment to penitentiary defense. A considerable number of defensores use some of the four narrative tropes discussed here, although in different shapes and scopes. The narrative construction of personal experiences indicates that defensores find sense and meaning from interpreting life events in their biographies as the basis for their professional engagement to the provision of legal aid. Narratives of identification For some defensores there is a clear connection between their pasts of precarity and marginalization and prisoners’ lives. In their testimonies, defensores draw equivalences between their lives and the lives of their clients and embrace the stigma of working with prisoners by creating rhetorical constructs that bridge the notion of “us” versus “them.” They knew about the vicissitudes and hardships of the prison world from a very young age. For them, their decision to be defensores is due to past experiences with the prison system. The parents of defensores Sonia and Tito went to prison when they were adolescents. Tito explains: “I went to law school because of the experience we had as a family. That led me to aspire to be a lawyer. I wanted to study, study law, and be a defensor.” Tito referred to his experience of having both father and mother in prison.I think that [his parents’ imprisonment] has helped me develop a skill, a particular sensitivity in my job that is different than [others]. [...] It is something that engenders a vision [about the prison system]. For instance, I don’t need someone to explain to me that women are subject to cavity searches. I saw it. But my colleagues have no idea how the prison world works. I believe that I am even thankful for what happened. So yes. I studied law partly because of that. Tito also asserts that he has developed a particular sensitivity and understanding of the prison world based on events in his adolescence. Professionals who have had similar personal experiences to those of the communities they serve are able to identify and situate the decisions and contexts that gave way to the current situation (Clair et al., 2016). By putting prisoners’ lives in perspective, defensores like Tito are able to understand and empathize with their current conditions. When asked how his family tried to understand and make sense of what happened, Tito responded:There is one reason only. This is rational. That’s the explanation behind crime. I can’t criticize someone who grew up in extreme poverty, like my parents did and the majority of prisoners do nowadays. You get it? I can’t ask them to behave like me. […] Their lives have been harsh. Very very harsh. That’s why they made that choice. [...] I see prisoners and I see my family. There has not been any social progress for them. [...] My father started pick-pocketing when he was 12 years old. He only reached 2nd grade. He finished high school while in prison. Note that Tito conveys “I see prisoners and I see my family” explicitly. He advances a less stigmatizing understanding of criminality by contextualizing the choices his parents made under strenuous circumstances. Moreover, Tito also believes that his unwavering commitment to indigent defense is essential to professional practice. For him, legal knowledge and technical skills are less important than the emotional commitment of lawyering for a cause. Later in the interview he demands the UPD embrace an institutional policy that commits to recruiting defensores who are personally empathetic to the hardships of the prison population and emotionally committed to indigent defense.The biggest problem that the Unit has stems from the fact that they only focus on technical aspects and leave aside the social [component][...] You have to make sure that applicants for this job are not only interested in the money. You get it? You have to make sure that they are passionate about this job. Sonia’s narrative also reflects an experiential past and provides a justification of her professional commitment based on personal events. She opened the interview with a strong statement.I have always been interested in criminal law. After obtaining my J.D. I tried to figure out how I could enter the Defensoría [Public Defender’s Office]. I never thought about being a fiscal [prosecuting attorney]. I have no interest in being a prosecutor, because they have a different agenda. Whereas I have always been interested in working as a defensora. To be honest, when I was a child my father went to jail. That’s why I am familiar with prisons. That helped me to decide what I wanted to do in life. […] Imagine me and my sister during prison visits. It was humiliating. I know how prison visits work. I know how humiliating the system is. I know how it is to leave the prison, go into your home and have yourself a cup of tea, knowing that your loved one remains locked up in prison. Stories of negative childhood experiences (violence, poverty, problematic situations in the family like criminal behavior, and encounters with law enforcement) assist defensores like Tito and Sonia in the creation of their professional selves. These defensores’ social origins and experiences allow them to be more attuned to the experiences of the imprisoned and to obtain positive meaning from their traumatic pasts. To some extent, they are “experts by experience,” for they have witnessed their relatives become involved in criminal activities and have had institutional contacts with the criminal justice system as users (similarly, Anderson et al., 2008). These experiences also provide them with the knowledge and perspective to authoritatively contest mainstream descriptions that demonize prisoners and to create counter-narratives about both offending and punishment (Uggen et al., 2017). They also feel encouraged to investigate problems or complications that prisoners endure that may never occur to other defensores who lack such experiences. The pasts of these defensores morph into an emotional and intellectual resource that is used as a way to understand and navigate the criminal justice system. By having experienced the prison system firsthand, these defensores aspire to dismantle common misconceptions about prisoners and look beyond the formal legal categories imposed by the criminal justice system. Their experience has helped them develop a sense of empathy that empowers them to fight for prisoners’ rights as if they were advocating for themselves and for their families in the past. These narratives of identification are inescapably connected to large-scale historical phenomena that have taken place in the Chilean higher education system. Since the 1980s, the proliferation of law schools in Chile gave high school students from marginalized backgrounds –like Tito and Sonia – the opportunity to study law and obtain a law degree. This is actually a very new development in the history of Chilean legal education: only the massive access to higher education of the past 30 years could have provided access to the children of prison inmates to studying law.6 Thus, defensores like Tito and Sonia are able to fulfill what they see as their purpose in life thanks to the possibilities that became available in the Chilean higher education market during the 80s. Tito and Sonia come from families that experienced the prison system first-hand and have been direct witnesses of the destructive operations of the Chilean criminal justice system. As structural explanations of professional commitment would suggest, their place in the social structure may have influenced their decision to become penitentiary defenders. Sustaining a structural approach, sociolegal scholar Margaret Etienne has hypothesized that US attorneys’ racial and ethnic backgrounds may explain engagement in a cause due to the ‘obligation thesis:’ because “they view the protection of the rights of the underprivileged as being in their self-interest” (2004: 1218). However, the findings of this study suggest that these defensores’ social origins and their tough life experiences do not automatically translate into their commitment to penitentiary defense. Defensores like Tito and Sonia engage in creative narrative processes in which they establish a connection between their personal biographies and their involvement in criminal indigent defense. Thus, it is possible to suggest that individual processes of narrative self-construction complement structural explanations of professional commitment. Narratives of privilege While some defensores build a direct connection between their lives and the prison system, others associate their pasts of affluence and wellbeing to their current moral values and commitment to public service. To do this, they embrace a narrative scheme of privilege. They describe childhoods of family affluence and economic wellbeing and arrange the plot points of their lives to envision their professional selves as morally responsible for the battle against human misery. For many defensores the idea of giving back to society emerges along with a sense of responsibility that logically leads to being a defensor. These defensores build their identity narratives based on —in their words —their families’ privileged pasts. They see themselves as enjoying a special advantage that most do not enjoy — let alone the prison population. Many of them depict their past selves as privileged children who lacked nothing. Today their gratitude for this privilege serves a resource to explain their desire to help the disadvantaged and work towards social justice. The stories of defensoras Eleanor and Sandra bring together disparate features in their lives to assemble a narrative that unifies and gives purpose to their profession. Eleanor, for instance, presents herself as a “privileged rebel:”When I started to work in prisons, my parents were in shock. My mom was like ‘I have taken care of you. I have always protected you and now you do this?’ They couldn’t make sense of it at that time, but I know that they have my back now. They have always supported me. Always. Always. Always. And I have always been kind of a rebel. In life in general. With injustice. This has increased over time. I always say to my dad that we have had many privileges in life; even up until today. The fact that I am working from home, in my apartment. All very nice. All very quiet. The fact that I go to the grocery store and can spend 100,000 Chilean pesos [close to $120 dollars] to buy three random things. That’s privilege there. From that position of privilege, we can do great things too. We have two paths to take. One is to take shelter in our privilege, or we can try to do our part. As simple as that. I, from my privilege – because I am privileged–I am contributing to society. I haven’t taken a vow of poverty, though. Far from that. But I am contributing to society. And I am helping many people. I am not saying that prisoners are all innocent. I have never said something like that. I have never said ‘free them all’. However, if you are in a prison you have the right to live in humane conditions. Period. That’s what I am fighting for. That’s my contribution to society. Eleanor revisits her past experiences and conveys the need she feels to give back to society as due to the blessings she received early in life. Eleanor’s narrative identity is a subjective construction that assists her in making sense of past experiences (her family affluence) in light of present events (her work as a defensora). The prosperity of her family has impacted her life: she can’t escape the inherent and long-term privilege that has benefited her and her family since childhood. Eleanor’s narrative construction of gratitude and indebtedness also helps her explain how she became the person that she is today: she has always been a “kind of a rebel” whose “rebellion” has increased over time. Her reconstruction of the past also provides her with a moral compass for her daily life, making it clear that her ethical values and beliefs compel her to contribute to society and help prisoners live in humane conditions through the institutional capacities of the UPD. This narrative of privilege provides coherence and temporal continuity between Eleanor’s past and present. It is worth noting that Eleanor also makes clear that she hasn’t taken “a vow of poverty.” Indeed, the Unit of Penitentiary Defense offers decent material conditions, including mid-level salaries and flexible working time arrangements. In Eleanor’s narrative of privilege, personal and material motivations simultaneously come together (see: Somers, 1994). As a side note, consider the testimony of Vicente, another defensor, who mockingly encapsulates this circumstance: “When someone starts teasing me for being a defensor I tell them: ‘I am a defensor. I defend criminals. I like it. I make money from it. And I am fucking good at it.’” Rational and emotional motivations converge in defensores’ narratives. They harmonize their perceptions of themselves and their desire for tangible rewards to coalesce in a meaningful narrative of commitment to the profession. Sandra also describes a background of family affluence. She explains that both of her parents went to college, with her father as a successful engineer and her mother having studied art theory. When explaining her motivation to work as a defensora she asserts that she sees it as a moral obligation.From my point of view, I see this as an obligation. Not as an obligation that someone imposed on me, but as an obligation that I personally assume– freely and happily. I have been extremely privileged. Note that my parents paid my tuition in college. I had to work to pay for books and transportation, but my father paid my college tuition. So, I have always felt that I am in debt to society. In my life I have always been so privileged, and I feel that I have to give it back to people who haven’t had any opportunities in life, who haven’t had access to the things I have had in life. Eleanor and Sandra provide their lives with a semblance of unity and purpose by connecting their internalized life stories of privilege and the moral duties that stem from that privilege to the professional space they inhabit –– the criminal justice system. The stories these defensoras tell about themselves require them to analyze their distant pasts, when they enjoyed advantages and economic wellbeing. These stories are accompanied by their sensitivity to the suffering of others. Similar to McAdams’ description of “generative narratives” (2001), these defensoras see their class privilege as the source of their duty to share their advantage and put their talents at the service of prisoners and their families. This is not trivial: this type of defensor interprets their life story in such a way that considers their professional selves as morally responsible for the battle against human misery in the prison system. For them, “giving back to society” emerges alongside a sense of responsibility that logically leads to their professional commitment to criminal indigent defense. Narratives of calling Defensores also use a narrative strategy that consists of examining their deep-rooted individual capabilities, personalities, and core convictions as manifested through different life scenes. Similar to previous studies on called professionals (Bloom et al., 2021), many defensores build cohesive life stories that demonstrate that they have always had the skills and motivation needed to be a good defensor. Their path of discernment entails a process of self-discovery, where preliminary life choices and career decisions may have proven wrong. However, once lifelong skills are recognized, the decision to become a defensor seems rather obvious. The notions of duty, fate, and destiny play an important role in explaining how life —the universe even — wanted these individuals to become advocates of social justice. The case of Valeska sheds light onto how some defensores build a definition of their past and present selves that naturally lead them to becoming a defensor. Even though she prepared for and aspired to go to medical school while in high school, she was not admitted. However, for her, the decision to study law is due to her exceptional oral skills and inherent sense of social justice. Ultimately, life circumstances helped her to discover her true self.What happens is that at first, I did not want to study law. I liked it at some point, during high school, as one of many career options, but I wanted to go to medical school. I took the PSU [the Chilean version of the SAT] and I did not reach the score for studying medicine. I was put on the waiting list. But my score was good for law school. I liked that idea because I did a lot of public speaking and was part of the debate academy during high school. I participated in some inter-school debate tournaments as well. So, I applied to law school. I always think about justice; about being able to help directly and concretely. Truth is that I was also among the top 10 students out of the 180 students entering Law school that year. That was very important to me. We can see that for Valeska, having oral and debate skills played an important role in her decision to study law. In her imaginary, a good lawyer also exhibits a sense of social justice and a desire to help people. She fits into this ideal type. Throughout the interview she makes it clear that she has both the professional skills required to be a defensora and a strong level of commitment to social justice. It does not really matter that law school was not her first option. Life showed her the right path to take in spite of her previous “faulty” preferences. These defensores feel that they “have something” within them that has enlightened their path to working within the prison system. Carlos explains his life stance as a child and the enigmatic discovery his parents had in his early childhood: that he was born to be a lawyer.When I was a child, I wanted to do something totally different. I really liked driving vehicles. A taxi. A bus even. But my father used to tease me. I liked defending my mother from everything. Whatever people said to my mom, I would defend her. My dad would always say to me ‘Hey, you’re going to be a lawyer’. Maybe that stuck with me since I was little and over time it increased. […] At the time I had to choose a career I said ’Ok. I’ll go to law school’. That was kind of a surprise for everyone, except for my parents. They said that they knew I was going to enter law school. Parents seem to know what their children like and want [...] For them it was a relief to know that I was going to pursue a career that I was supposedly meant to choose as a child. […] In fact, I have always thought that we all have to be equals under the law. Everyone should have the opportunity to see their rights being protected [...]. From that point of view, I was interested in protecting the vulnerable. Think of children, or victims without economic resources, or defendants. That has always been my motivation. To level the playing field. At the center of defensores’ vocation, there is the feeling of being born with the skills and aptitudes to be a lawyer. Carlos makes a connection between his ever-present inclination for justice and his work as a lawyer. This is the connection researchers have found called professionals make between their gifts and talents and the particular domains of work for which those passions and endowments seem particularly fitting (Bunderson & Thompson, 2009). Defensores revisit and select moments and episodes of their pasts in a quest for evidence that would demonstrate how their early talents constitute the antecedents for their work today. These connections between the personal past and the professional present help narrators not only generate consistency and stability in their sense of self, but to explain and justify their competence for their professional practice (McAdams & Guo, 2015). Defensora Fabiola began our interview explaining how being a defensora has been a blessing for her.I never thought about doing this job. In fact, I didn’t even know that there was this profession of penitentiary defender. I never studied it in law school. It was not a thing to me. I wanted to be a public defender, kind of like Don Quixote. Now I see this [being a penitentiary defender] as a blessing. I decided to go to law school knowing that I wanted to help. That did not go away after I choose this path, because I still want to help. You get it? I just fell into the right place. A place where I can do things and help people who really need it and that are left unheard. These narratives involve the idea that life “drove” these prospective defensores to the right place. Similar to Bloom’s narratives of discernment (Bloom et al., 2021), Fabiola’s narrative of calling prompts her to believe that her ever-present passion for social justice inevitably propelled her to embrace her professional role as a defensora. It is almost as if she was destined to advocate for convicted prisoners and become a legal aid lawyer in the criminal justice system since the day she was born. Narratives of admiration Legal professionals often recount the importance of role models in their childhood, adolescence, and university years. Mentors can provide advice, sage counsel, and positive support as professionals envision their work. Studies have shown that the presence of models of excellence in a profession offer plausible archetypes of what a committed professional might look like and depict ideal types on to which beginners can map themselves (Bloom et al., 2021). Findings in the present study reveal that mentor relationships operate as a narrative resource for defensores to understand themselves as loyal advocates of a social cause. Defensores honor meaningful relationships they had with mentors in their pasts and therefore create a “past of loyalty,” where they see themselves as honoring the intellectual and professional tradition put forward by their mentors. Defensores as mentees see themselves as the heirs of a tradition of commitment to social justice and conceive of their professionalism as the continuation of a path that was forged by others in the field. Role models for defensores can emerge during their childhood or adolescence, but they appear more prominently during their college years. Figures of academic authority act as mentors who helped future defensores to find their true vocation and mission in life. Penal development is filled with stories of academic and professional mentorship, but very few of them explore how these relationships unfold. Defensores’ narratives of the present hinge on their view of their relationship with role models in the past. For instance, when I asked defensor Andrés about the origins of his motivation for being a defensor, he mentions his law school professor, Arturo Zebada.When I entered law school, I always thought I was going to be a fiscal [prosecutor] to catch the bad guys. Like I was going to be the city’s hero. But I had the opportunity to meet this criminal law professor, Arturo Zebada. He showed us the other side of the coin; about the ways in which public defenders provide legitimacy to the criminal justice system, this terrible monster. That was a turning point. I started changing. I always liked criminal law, but that was the point in which I decided to go down that road [public defense]. I then had this vision about me being a defensor. That became a professional goal, but also a personal goal. Tito recalls Rodrigo Cerda, a law school professor who connected with him and his fellow students at a very deep level. This type of guide instills and praises the capabilities and convictions of their pupils. Tito explains that Cerda inspired him and his classmates to be critical but also passionate regarding the legal profession. Cerda used to give books to his students and encouraged them to write essays and reflections about the uses and abuses of the law. Relying on the adamant language common in Chilean conversations Tito asserts:Rodrigo was key. Key. Key. Key. He became a leader among us. He formed this group even though he knew we were poor students. None of us was a shining star, but he saw something in us. He taught us the core values of law. Today I feel that being a defensor is letting me do something with the core principles that I learned in those years. Another defensor, Carlos, reflects on the importance of public defender Juan Ignacio Lafontaine for his decision of joining the Defensoría. I asked him what was it about Lafontaine that motivated him to be a defensor.Professor Lafontaine –I still call him Professor Lafontaine- had the courage of a defensor. That courage of knowing that you may give everything up for lost, but your client still deserves to be defended. Clients have rights that must be protected, regardless of whether they have been convicted or not. We all have the right to defense, to equality of arms. There must be a balance [in a criminal trial]. That is how Professor Lafontaine convinced me and another colleague to choose this path. He inspired us to decide: ‘I want to study this, dedicate myself to this’. We saw him as a model, so to speak, from the point of view of litigation, his performance in court, and the passion he devoted to his work. That was what motivated me to be a defensor. In professional circles, a mentor is usually somebody that also provides encouragement and intellectual stimuli (Sawicki & Siméant, 2010: 90). Individuals’ embeddedness in a network of mentorship or reciprocity heightens their sense of responsibility to their peers. Social networks support certain forms of sociability and identities that contribute to make commitment effective and permanent (Zaloznaya & Nielsen, 2011: 926). The stronger the ties to the network the higher the costs involved in relinquishing professional identities and practices, not only in terms of professional stability, but also in terms of abandoning a source of meaning and self-understanding (Sawicki & Siméant, 2010: 91). It is worth noting that a historical key component of the socialization in the legal profession in Chile is the provision of legal training to law students through the National Legal Aid Service (Corporación de Asistencia Judicial). Law students in Chile have to go through a mandatory six-month unpaid internship after finishing law school in a public legal service. This internship was established to provide free legal aid for the poor, but also to shape “the spirit of a ‘socially conscious’ legal profession” through the training of younger generations of lawyers who would be sensitive to human misery in a spirit of social solidarity (Gonzalez Le Saux, 2022: 259, 264). Moreover, human rights discourses that have accompanied the installation of the Reforma Procesal Penal are also likely to have shaped defensores’ professional ethos. Thus, the spirit of solidarity that is manifest in defensores’ personal accounts stems from broader historical trends within the socialization of the legal profession. Taken together, these examples show how role models help defensores build expectations and ideals associated with the legal profession. Andrés, Tito, and Carlos seek to honor the presence of those role models during their college years – their rhetoric, their values, their authority in the field – by putting forward the moral standards they ascribe to their professional roles. These moral standards stem from personal interactions, but also from the founding principles of the legal profession in Chile. Thus, they create a narrative of an offer, an invitation, a proposition to fight against the abuses and oppression of the criminal justice system. Andrés, Tito, and Carlos decided to honor that invitation by joining and remaining in the UPD. That also meant, for them, being a member of a communal experience that aspires to protect collective values and ideals about criminal justice. Being a defensor is thus being loyal to that invitation from a mentor in the past. Conclusion Why do some attorneys engage in the provision of criminal indigent defense despite the adverse work conditions that characterize the practice? (Ashforth & Kreiner, 1999; Baćak et al., 2020; Curran & Noone, 2007; Emmelman, 1993; Etienne, 2004: 1244; Libedinsky, 2015; McIntyre, 1987; Menkel-Meadow, 1998; Stippel et al., 2020; Venegas, 2018; Zaloznaya & Nielsen, 2011).The present study uses the case of penitentiary defenders in the Chilean Unit of Penitentiary Defense (UPD) to explore lawyers’ professional commitment to the provision of legal aid within the Chilean criminal justice system despite high caseloads, institutional resistance to the recognition of prisoners’ rights, and limited resources. Findings indicate that defensores construct biographical narratives that reflect the different ways in which professionals reinterpret their childhood, adolescence, young adulthood, and law school years in light of their present circumstances. Defensores build and find explanations for their current professional engagement in their early interactions with the criminal justice system (narratives of identification), their intention to pay back the early advantages they had in life (narratives of privilege), and their sense of having a deep-rooted lifelong moral aptitude to advocate for the weak (narratives of calling). Also, the presence of role models offers defensores an example of what advocating for justice might look like and it also encourages them to live up to what they consider to be shared expectations in the profession (narratives of admiration). On the one hand, this research complements current ideas about how penal projects endure and succeed. Scholars of penal change have explained how nation-level structures (Garland, 2001; Lacey, 2008; Lappi-Seppälä, 2011; Savelsberg, 1994; Tonry, 2009) and political struggles (Goodman et al., 2017; Loader & Sparks, 2004: 16; Page, 2012; Rubin, 2015) impact the shape and scope of penal institutions. By studying the agentic aspects of professional commitment to criminal justice institutions, this research adds a novel micro-level perspective to macro- and meso- approaches to penal change. On the other hand, it also complements existent theories about lawyers’ commitment to indigent defense. Traditional individual-level explanations of professional engagement point to personality traits associated with altruistic motivations, the rational assessment of the costs and benefits involved in the practice, and individuals’ place within the social structure (Baćak et al., 2020; Etienne, 2004; Menkel-Meadow, 1998). Studying the narrative connection defensores make between their personal biographies and current professional practice adds a new perspective to the agentic aspects of professional commitment to criminal justice institutions. It is also worth noting that the narrative categories that emerged from this study are in dialogue with analytical categories previously identified by narrative studies of professional commitment. The “narratives of privilege” resemble the idea of “generative narratives” put forward by Dan McAdams et al. (1997), in which early family blessings motivate the desire of “giving back to society”. The “narratives of calling” also resemble the narratives of discernment described by Bloom et al. (2021), where narrators describe a journey towards what they see as their destiny in life. I have adapted some of the theoretical advancements of narrative studies to create new analytical categories that may better respond to the universe of meaning of the criminal justice system. In terms of its policy implications, this study can aid public policy makers in the identification of professionals that consistently commit to their practice, provide adequate legal services, and remain in the job. First, defensores’ professional narratives can have a great influence into how the provision of indigent defense as a penal policy is implemented on the ground. Second, strong professional narratives may empower defensores to remain committed to the provision of indigent defense despite adverse working conditions. As has been stated elsewhere, a solid identity integration between self and work may influence professionals’ career success, sense of wellbeing, and occupational satisfaction (Bloom et al., 2021). Finally, defensores can mobilize penal change above and beyond the formal duties of providing legal service provision. Future studies on legal defense should explore how defensores put into practice the narratives that they have created for themselves. Certainly, a narrative approach to professional commitment has important limitations. First, interviews do not allow for statements of a causal relationship between defensores’ narratives and their ensuing behavior – such as remaining in the profession or providing quality legal services. An observational approach that captured individuals’ professional behavior could complement the narrative findings present in this study. Second, the sociopolitical context of narration is key for understanding the substance and limits of professional narratives. As Presser argues: “We do not choose just any identities we wish; we are in no position to make ourselves up from scratch” (Presser, 2016: 146). Here, I have considered the influence of large-scale transformations in Chile, such as the reform of the criminal justice system, the growth of legal education coverage, and new trends in the expansion of bureaucratic infrastructure. However, historians are likely to provide a more complete landscape of the structural changes that may influence the shape and scope of defensores’ experiences and narratives. Third, the majority of the 37 defensores interviewed for this study shared an internalized, evolving story of their professional selves through the narrative examination of their personal biographies. However, not all defensores resort to a narrative reconstruction of their personal experiences. Future studies could formally test the coexistence or divergence of different mechanisms of professional commitment. A more formal and comprehensive comparison between competing theories of career choice and engagement (such as personalistic, rational-choice, and structural approaches) could provide a clearer picture of penal practitioners’ professional engagement in the criminal justice system. Data availability The datasets generated and analyzed during the current study are not publicly available due the fact that they constitute an excerpt of research in progress but are available from the corresponding author on reasonable request. Declarations Conflict of interest The author certifies that they have no affiliations with or involvement in any organization or entity with any financial or non-financial interest in the subject matter or materials discussed in this manuscript. 1 Following the Spanish denominations throughout the text I use the terms “defensor,” which is masculine, “defensora,” which is feminine, “defensoras” which is plural for feminine, and “defensores,” which is plural for both masculine and feminine. 2 Both public and penitentiary defenders are called “defensores” in the Chilean criminal justice system. Here I will use the term defensores for penitentiary defenders exclusively unless indicated otherwise. 3 It is worth noting that national public programs that provide public legal assistance to convicted prisoners are relatively rare. The United States lacks a functioning legal services system for any group in the population (Sandefur, 2015) and publicly funded programs for condemned populations do not exist (Calavita & Jenness, 2015). Legal reforms in the U.S. have actually limited prisoners’ access to legal recourse and eliminated governmental funding for legal service programs (Zaloznaya & Nielsen, 2011). Prisoners generally have few options to file lawsuits before state or federal courts, among which are acting through pro se legal representation or jailhouse lawyers, receiving legal services from law school clinics or private organizations, or paying for post-conviction lawyers (Schlanger, 2003). 4 Ethical approval for this research was granted by the University of Minnesota’s Institutional Review Board. 5 The sampling approach relied on three main strategies: convenience, snowball, and stratified sampling. I used a convenience sampling strategy in the first stage. As a lawyer formerly involved in an NGO that provides free legal aid to convicted prisoners, I reached out to two defensores of my trust that had previously worked with the organization to provide legal training on prison issues to volunteer law students. These 2 defensores provided further information about well-regarded colleagues (n = 2). In the second stage, I used snowball sampling to interview 5 more defensores (n = 5) based on their suggestions. I also reached out via email to two executive directors from the Defensoría Nacional in charge of assessment performance to request information about defensores known for their success. I had met these two executives in 2014 because of my participation in an academic seminar organized by the Defensoría. Three more defensores were contacted using this approach (n = 3). A first round of coding from these first 10 interviews made clear that a broader approach was necessary to achieve a better understanding of defensores’ experiences overall. In the third stage, I used stratified sampling and expanded my search to defensores working throughout the country. I sent a request to Defensoría National through the Chilean Freedom of Information System to have a list of all the defensores that had worked and were currently working at the Unit of Penitentiary Defense from 2009 to 2021 indicating their regions of work and contact information. In total, the list submitted included 38 former defensores and 54 defensores working at the Defensoría at the time of the request. I stratified this list expecting to interview at least one defensor o defensora working in each of the 16 Chilean regions. Drawing on this criterion, I sent out formal invitations to 32 defensores and 11 former defensores. I had a 50% response rate and conducted 18 interviews with current defensores. The 50% of non-response corresponds to 11 defensores that didn’t reply to my requests, 4 defensores who explicitly declined to participate, 2 defensores that demonstrated initial interest to participate, but discontinued their communication in the process of scheduling a meeting, and one defensora who scheduled an interview with me but didn’t attend the meeting. Out of 11 former defensores, 9 responded to my requests. I conducted 18 interviews with defensores and 9 with former defensores using this final approach (n = 27). I succeeded in interviewing at least one defensor per Chilean region.” 6 I am thankful to one of the reviewers for highlighting this circumstance. Different versions of this paper were presented at the Law and Society Virtual Conference (2021), the LSA Graduate Student & Early Career Workshop (2021), the New Directions in Law and Society Workshop at the University of Massachusetts Amherst (2021), the American Society of Criminology (2021), and the Sociology Research Institute at the University of Minnesota (2021). The author would like to thank Javier Wilenmann and Pilar Larroulet for the organization of the presentation of this paper at Universidad Adolfo Ibañez and Universidad Católica de Chile, respectively. I thank Diego Rochow, Ashley Rubin, Larisa Zerbino, Cesar Bazan, Ana María Morales, Matt Clair, Caity Curry, Amber Powel, Victoria Piehowski, Jeanne Hersant, Ulda Figueroa, Michael Walker, Kathy Hull, Lisa Hilbink, Michael Tonry, Michelle Phelps, Katrina Heimark, and Chris Uggen for helpful comments on earlier drafts of this paper. I also gained insight from conversations and reading recommendations with narrative criminologists Lois Presser and Sveinung Sandberg. Comments by Josh Page were crucial for the development of the argument. Alicia Salinero, Rodrigo Lillo, Alejandro Gómez and Pablo Aranda provided excellent guidance into the field of penitentiary defense. I am also deeply grateful to the defensores that shared their life experiences with me. Finally, the author would like to thank the editors and the anonymous reviewers from Crime, Law, and Social Change for their very helpful feedback. Not everyone agreed with the argument, but their responses were both valuable and encouraging. Any errors remain my own. Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Anderson WG Williams JE Bost JE Barnard D Exposure to death is associated with positive attitudes and higher knowledge about end-of-life care in graduating medical students Journal of Palliative Medicine 2008 11 9 1227 1233 10.1089/jpm.2008.0058 19021486 Ashforth BE Kreiner GE How can you do it?”: dirty work and the challenge of constructing a positive identity Academy of Management Review 1999 24 3 413 434 Ashforth BE Schinoff BS Identity under construction: how individuals come to define themselves in organizations Annual Review of Organizational Psychology and Organizational Behavior 2016 3 111 137 10.1146/annurev-orgpsych-041015-062322 Baćak V Lageson SE Powell K “Fighting the good fight”: why do public defenders remain on the job? Criminal Justice Policy Review 2020 31 6 939 961 10.1177/0887403419862317 Bergoglio, M. I. (2009). Diversidad y desigualdad en la profesión jurídica: consecuencias sobre el papel del Derecho en América Latina. Revista Via Iuris (6), 12–28. https://www.redalyc.org/pdf/2739/273920944003.pdf Bloom M Colbert AE Nielsen JD Stories of calling: how called professionals construct narrative identities Administrative Science Quarterly 2021 66 2 298 338 10.1177/0001839220949502 Bruner J The narrative construction of reality Critical Inquiry 1991 18 1 1 21 10.1086/448619 Bunderson JS Thompson JA The call of the wild: zookeepers, callings, and the double-edged sword of deeply meaningful work Administrative Science Quarterly 2009 54 1 32 57 10.2189/asqu.2009.54.1.32 Calavita K Jenness V Appealing to justice: prisoner grievances, rights, and carceral logic 2015 University of California Press Chacón, R. (2015). The university as an agent of social change: The Chilean experience (Doctoral Dissertation, Auckland University of Technology). Charmaz K Stories of suffering: subjective tales and research narratives Qualitative Health Research 1999 9 3 362 382 10.1177/104973239900900306 Christiansen CH Defining lives: Occupation as identity: an essay on competence, coherence, and the creation of meaning The American Journal of Occupational Therapy 1999 53 547 558 10.5014/ajot.53.6.547 10578432 Clair M Daniel C Lamont M Destigmatization and health: Cultural constructions and the long-term reduction of stigma Social Science & Medicine 2016 165 223 232 10.1016/j.socscimed.2016.03.021 27020492 Curran L Noone MA The challenge of defining unmet legal need Journal of Law and Social Policy 2007 21 63 89 Czarniawska B Narratives in social science research 2004 Sage Dannefer D Kelley-Moore J Huang W Opening the social: sociological imagination in life course studies Handbook of the life course 2016 Springer 87 110 Emmelman DS Organizational conditions that facilitate an ethical defense posture among attorneys for the poor: observations of a private nonprofit corporation Criminal Justice Review 1993 18 2 221 235 10.1177/073401689301800205 Etienne M The ethics of cause lawyering: an empirical examination of criminal defense lawyers as cause lawyers Journal of Criminal Law & Criminology 2004 95 4 1195 1260 Fischer R On fact and fiction—the structure of stories that the brain tells to itself about itself Journal of Social and Biological Structures 1987 10 343 351 10.1016/0140-1750(87)90046-7 Fine GA Justifying work: occupational rhetorics as resources in restaurant kitchens Administrative Science Quarterly 1996 41 1 90 115 10.2307/2393987 Fleetwood, J., Presser, L., Sandberg, S., & Ugelvik, T. (2019). “Introduction”. In J. Fleetwood, L. Presser, S. Sandberg, & T. Ugelvik (Eds.), The emerald handbook of narrative criminology. Emerald Publishing Limited. Garland D The culture of control: crime and social order in contemporary society 2001 University of Chicago Press Garland D Penality and the penal state Criminology 2013 51 3 475 517 10.1111/1745-9125.12015 Giddens A Modernity and self-identity: self and society in the late modern age 1991 Polity Press Glaser, B. G., & Strauss, A. L. (2017). Discovery of grounded theory: strategies for qualitative research. Routledge. González, L., & Saux, M. (2022). Training and disciplining lawyers through legal aid: Chile, 1925-1960s. In F. Batlan, & M. Vasara-Aaltonen (Eds.), Histories of legal aid: a comparative and international perspective (pp. 253–286). Palgrave Macmillan. Goodman, P., Page, J., & Phelps, M. (2017). Breaking the pendulum: the long struggle over criminal justice. Oxford University Press. Hathazy P Remaking the prisons of the market democracies: new experts, old guards and politics in the carceral fields of Argentina and Chile Crime Law and Social Change 2016 65 3 163 193 10.1007/s10611-015-9579-1 Herrera F Torres R Nicolis O Salas R Characterization of the chilean public procurement ecosystem using Social Network Analysis IEEE Access: Practical Innovations, Open Solutions 2020 8 138846 138858 10.1109/ACCESS.2020.3011947 Hilbink, L. (2007). Judges beyond politics in democracy and dictatorship: Lessons from Chile. Camnbridge. Cambridge University Press. Ibarra H Provisional selves: experimenting with image and identity in professional adaptation Administrative Science Quarterly 1999 44 4 764 791 10.2307/2667055 Ibarra H Barbulescu R Identity as narrative: prevalence, effectiveness, and consequences of narrative identity work in macro work role transitions Academy of Management Review 2010 35 1 135 154 Lacey N The prisoners’ dilemma: political economy and punishment in contemporary democracies 2008 Cambridge University Press Langer M Revolution in latin american criminal procedure: diffusion of legal ideas from the periphery The American Journal of Comparative Law 2007 55 4 617 676 10.1093/ajcl/55.4.617 Lappi-Seppälä T Explaining imprisonment in Europe European Journal of Criminology 2011 8 4 303 328 10.1177/1477370811411459 Libedinsky S Rediseño del modelo de defensa penitenciaria para adultos privados de libertad en el nuevo sistema procesal penal Revista Estudios de Políticas Públicas 2015 1 1 226 245 Loader I Sparks R For an historical sociology of crime policy in England and Wales since 1968 Critical Review of International Social and Political Philosophy 2004 7 2 5 32 10.1080/1369823042000266495 McAdams DP The psychology of life stories Review of General Psychology 2001 5 2 100 122 10.1037/1089-2680.5.2.100 McAdams D Bauer J Emmons R McCullough M Gratitude in modern life: its manifestations and development The psychology of gratitude 2004 Oxford University Press 81 99 McAdams DP Guo J Narrating the generative life Psychological Science 2015 26 4 475 483 10.1177/0956797614568318 25749704 McAdams D Diamond A de St Aubin E Mansfield E Stories of commitment: the psychosocial construction of generative lives Journal of Personality and Social Psychology 1997 72 3 678 694 10.1037/0022-3514.72.3.678 McAdams D de St Aubin ED A theory of generativity and its assessment through self-report, behavioral acts, and narrative themes in autobiography Journal of Personality and Social Psychology 1992 62 6 1003 1015 10.1037/0022-3514.62.6.1003 McIntyre LJ The public defender: the practice of law in the shadows of repute 1987 University of Chicago Press McLean K Pasupathi M Pals JL Selves creating stories creating selves: a process model of self-development Personality and Social Psychology Review 2007 11 3 262 278 10.1177/1088868307301034 18453464 Mead GH Mind, self and society 1934 Chicago University of Chicago Press Menkel-Meadow C Sarat A “The causes of cause lawyering: toward an understanding of the motivation and commitment of social justice lawyers.” Cause lawyering: political commitments and professional responsibilities 1998 Oxford Oxford University Press 31 68 Mori, A. (2020). Employment relations in outsourced public services: working between market and state. Employment relations in outsourced public services (pp. 1–29). Palgrave Macmillan. Ndhlovu, E. (2021). Qualitative data collection under the ‘New Normal’ in Zimbabwe. In H. Kara & S.-M. Khoo (Eds) Researching in the age of COVID-19 Vol 1: Volume I: Response and reassessment (9–62). Policy Press. Norton L Johnson J Woods G Burnout and compassion fatigue: what lawyers need to know University of Missoury-Kansas City Law Review 2015 84 987 1002 Page J Simon J Sparks R Punishment and the penal field The SAGE handbook of punishment and society 2012 Sage 152 166 Presser L Criminology and the narrative turn Crime Media Culture 2016 12 2 137 151 10.1177/1741659015626203 Rubin A A neo-institutional account of prison diffusion Law & Society Review 2015 49 2 365 400 10.1111/lasr.12136 Sandefur RL What we know and need to know about the legal needs of the public South Carolina Law Review 2015 67 2 443 459 Savelsberg JJ Knowledge, domination, and criminal punishment American Journal of Sociology 1994 99 4 911 943 10.1086/230367 Sawicki F Siméant J Decompartmentalizing the sociology of activist commitment. A critical survey of some recent trends in french research Sociologie du Travail 2010 52 e83 e109 10.1016/j.soctra.2010.06.005 Somers MR The narrative constitution of identity: a relational and network approach Theory and Society 1994 23 605 649 10.1007/BF00992905 Schlanger M Inmate litigation Harvard Law Review 2003 116 6 1555 1706 10.2307/1342709 Stippel J Medina P Lillo R Obstáculos en la activación de derechos en el marco de la defensa penitenciaria chilena Revista Brasileira de Direito Processual Penal 2020 6 3 1735 1775 10.22197/rbdpp.v6i3.356 Swen CP Talk of calling: novice school principals narrating destiny, duty, and fulfillment in work Educational Administration Quarterly 2020 56 2 177 219 10.1177/0013161X19840387 Tonry M Explanations of american punishment policies: a national history Punishment & Society 2009 11 3 377 394 10.1177/1462474509334609 Thorne A Putting the person into social identity Human Development 2004 47 6 361 365 10.1159/000081038 Ugelvik T Techniques of legitimation: the narrative construction of legitimacy among immigration detention officers Crime Media Culture 2016 12 2 215 232 10.1177/1741659016648180 Uggen C Horowitz V Stewart R Public criminology and criminologists with records The Criminologist 2017 42 1 3 7 Universidad Diego Portales. (2008). Informe Anual de Derechos Humanos: Condiciones Carcelarias (pp. 77–133). Ediciones Universidad Diego Portales. van Hulst M Storytelling at the police station: the canteen culture revisited British Journal of Criminology 2013 53 4 624 642 10.1093/bjc/azt014 van Hulst M Ybema S From what to where: a setting-sensitive approach to organizational storytelling Organization Studies 2020 41 3 365 391 10.1177/0170840618815523 Venegas J El defensor penitenciario como fiscalizador de la actividad penitenciaria en el proceso sancionatorio administrativo Revista de la Justicia Penal 2018 12 229 309 Wilenmann J Neoliberal politics and state modernization in chilean penal evolution Punishment & Society 2020 22 3 259 280 10.1177/1462474519882974 Villalonga, C. (2021). Market, specialization, and rights: lawyers go behind social modernization in chile. Lawyers in Society 20 years later. Hart Publishing. Zaloznaya M Nielsen LB Mechanisms and consequences of professional marginality: the case of poverty lawyers revisited Law & Social Inquiry 2011 36 4 919 944 10.1111/j.1747-4469.2011.01256.x
PMC009xxxxxx/PMC9922645.txt	==== Front Psychol Learn Teach Psychol Learn Teach PLJ spplj Psychology Learning and Teaching 1475-7257 2057-3022 SAGE Publications Sage UK: London, England 10.1177/14757257231155250 10.1177_14757257231155250 Articles I Believe I Can Try: Self-Efficacy, Pandemic Behaviors, Coping, and Learning https://orcid.org/0000-0002-3542-4378 Gurung Regan A. R. Byers Stephanie Grapentine Jor Stone Arianna 2694 Oregon State University , United States of America Regan A. R. Gurung, Oregon State University, United States of America. Email: [email protected] 9 2 2023 7 2023 9 2 2023 22 2 124136 © The Author(s) 2023 2023 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. While colleges and universities grapple with delivering instruction face-to-face during the pandemic, there is still a lot to learn from remote teaching experiences. The present study aimed to predict self-reported learning during the first year of the pandemic. Building on previous scholarship on the topic, we focus on the moderating effects of self-efficacy, and the mediating effects of coping styles on the relationship between stress and self-reported learning experiences. We also included self-perceptions of class effort, the instructor, and changes in class, personal, professor, and health behaviors. Students (N = 272) in Introductory Psychology classes participated in an online survey as part of a class research requirement. Analyses demonstrated that self-efficacy predicted differences in many measures associated with learning and predicted learning over and above all other variables entered in a hierarchical regression. The relationship between stress and learning was mediated by coping, but not moderated by self-efficacy. These results suggest student beliefs about their ability to perform online are important to learning outcomes, but coping mechanisms mediate the relationship of stress and learning. Especially while teaching during pandemic times using different modalities, instructors will do well to directly address students’ perceptions of their own ability and build self-efficacy. Self-efficacy pandemic learning introductory psychology typesetterts19 ==== Body pmcIntroduction Teaching and learning have changed significantly since the onset of the COVID-19 pandemic (Gurung & Plaza, 2023). The wear and tear of the last few years continues to add up with expected consequences. Faculty report students struggle to engage with material (Fox et al., 2020) and students report difficulty staying motivated (Means et al., 2020). While many higher education institutions returned to in-person instruction in Fall 2021, some colleges and universities continued using remote learning. The emergence of highly infectious strains of COVID-19 (e.g., Delta, Omicron) required many institutions to utilize remote learning for short periods throughout 2022. It is clear that higher education will utilize remote learning again in the future (Daniela & Visvizi, 2022). Our experiences have taught us much that may help shape our future efforts to provide modified modalities in the event of emergency or otherwise. Indeed, a growing body of scholarship on the subject provides significant insight on this matter (Daniela & Visvizi, 2022; Gurung & Plaza, 2023). There are a number of investigations into key elements of the teaching-learning equation. Studies assessed different approaches to asynchronous learning, student study habits, objective and subjective learning, satisfaction with education, and barriers to learning (Gonzalez-Ramirez et al., 2021; Gurung et al., 2022; Keržič et al., 2021; Kim et al., 2021a; Schreiber, 2021), all of which were impacted by the transition to emergency remote teaching modalities during the COVID-19 lockdowns. In this study, we build on previous work to take a more nuanced look at pandemic learning. Inspired by calls to take a holistic approach to examining learning (e.g., pedagogical ecology; Daniel & Poole, 2009), utilize a systemic approach (e.g., Learning Sciences; Sawyer & Dunlosky, 2019), and investigate moderators and mediators of learning (Gurung & Hackathorn, 2018), especially in the unique learning context of pandemic learning, we selected a diverse set of behaviors and attitudes suggested to be important in past research. In light of the increased stress experienced during the COVID-19 lockdowns and the proven role of coping in reducing stress (Gruenewald & Wang, 2019; Nuere et al., 2022), we were especially interested in the roles of both stress and coping on student learning outcomes. Thus, we focused both on student stress and their subjective reports of learning, and measured student study behaviors and student perceptions of their courses and their instructors. We tested potential moderators (e.g., self-efficacy) and mediators (e.g., coping) of the stress and perceived learning relationship. The Role of Self-Efficacy Self-efficacy, the personal belief that one can accomplish a task, has long been a significant variable in psychological research, particularly concerning learning (Bandura, 2013; Kim et al., 2021b). As suggested by expectancy value theory, believing one can succeed has a significant effect on motivation, in that students will focus more on activities that they expect to succeed in (e.g., Wigfield & Eccles, 2000). Self-efficacy's role in motivation is especially evident in students’ willingness to accept technology enhanced learning (Gurung & Stone, 2020; Rosli & Saleh, 2022). Remote learning was a new modality for most students and faculty, but self-efficacy remains a key variable in predicting learning outcomes. Recent research indicates the self-efficacious beliefs of students based on educational delivery method (e.g., remote vs. face-to-face), predicts final exam scores. A study conducted with 649 students in April 2020 examined live, synchronous classes (Gurung & Stone, 2020). Researchers measured learning objectively using class exam scores and factored in key contextual features such as class behaviors, attitudes towards the class, and perceptions of the instructor. Students who believed they would do well online achieved higher exam scores and reported greater skill development than students who believed they would only do well in face-to-face classes. This specific self-efficacy, termed Modality-Based Self-Efficacy (MBSE; Gurung & Stone, 2020), also predicted the degree of changes in learning behaviors during the pandemic. The present study extends this work. A key goal of the present study was to again focus on the effects of self-efficacy while also factoring in key personal factors, including those mental health factors most likely to be exacerbated by conditions of the pandemic. Based on the aforementioned research, we expected the belief of success in online classes to moderate the relationship between pandemic stress and perceived learning in remote courses. Additionally, in order to better ascertain the ways in which personal behaviors around mental health factors would impact perceptions of learning, we also chose to focus on coping. Stress, Coping, and Learning The relationship between college students’ coping strategies and learning outcomes has been especially strained during the COVID-19 pandemic (Bathallath & Brahimi, 2022). In numerous studies, college students reported that the abrupt transition to online learning, prolonged time spent in an online learning environment, and technological concerns have led to increased frustration, anxiety, and stress about school (e.g., Browning et al., 2021; Lederer et al., 2021). As effective coping strategies provide students with a buffer against major stressful events (Gori et al., 2020), the ramifications of having poor/underdeveloped coping strategies can result in increased levels of psychological stress (Yang et al., 2020, 2021); arguably this may be the case for individuals who employ maladaptive or negative coping techniques. Given the natural relevance of coping behaviors and facing stress in the context of pandemic education, it is important to include both these variables in studying learning (Bamber & Schneider, 2022). Experimental designs show acute stress increases cognitive-effort avoidance (Bogdanov et al., 2021), findings mirrored in classroom studies. For example, students reported significant health disruptions, and increases in anxiety and mindless tech use while reporting significant decreases in motivation and the ability to focus (Giuntella et al., 2021; Hicks et al., 2021). In another study, students moving to remote learning decreased their social connections with peers, professors, and the college community (Gonzalez-Ramirez et al., 2021). Healthy habits connected to exercise and eating during the remote portion of the term were similarly negatively impacted. The pandemic clearly influenced how students coped, which influenced how they functioned and felt, suggesting the role of coping as a mediator. Important Correlates of Learning In addition to measures of stress, coping, and learning, we selected variables shown to relate to students’ academic performance. In particular, research has established that study behaviors, ratings of the professor, and student and instructor classroom behaviors all predict learning (Dunlosky et al., 2013; Gurung et al., 2022; Richmond et al., 2021). For example, an instructor's behaviors can also play important roles in student learning, especially in influencing student effort (Geier, 2022). In addition to student study techniques and their views of their instructor's behaviors, a holistic view of student learning must also include their health behaviors (Schmid et al., 2021). It is reasonable to suggest that such behaviors would be significantly impacted by the changes imposed on society and the learning environment by the pandemic. In addition, we also included variables such as personality (e.g., the Big Five) which are often predictive of behaviors in psychological research (Gosling et al., 2003). While the use of some of the variables we included is primarily exploratory and their predictive power during the pandemic is yet to be established, research shows they each can play important roles in learning. In pedagogical research, study designs often have to focus on a small set of variables due to the difficulties of using active classrooms versus a lab setting. This often results in only few potentially confounding variables being measured. We explicitly planned to expand our focus beyond our key research questions to allow for examinations of more relationships. Additionally, having a better picture of the associations between key factors when studying a still novel form of learning modality (remote learning) will enhance future pedagogical planning. Consequently, we included numerous measures such as personality in our design. The Present Study This study had four main research questions using key variables from previous studies of learning: What are the associations between key factors (stress, coping, personal characteristics, study behaviors, and perceptions of the class, professor, and learning) during remote learning? Does self-efficacy moderate the relationship between stress, coping, and learning? Does coping mediate the relationship between stress and learning? Does self-efficacy predict self-reported experiences of learning and class quality, beyond personal factors and class ratings? We predicted that self-efficacy would moderate the stress-perceived learning relationship and predict a unique portion of variance in perceived learning and related experiences, while coping would be a significant mediator. Method Participants Undergraduate students (N = 308) at a large west coast university started the survey, but 36 (11.7%) did not proceed past the consent page (2% progress). Of the remaining 272 students, 218 (70.8%) were female, 46 (14.9%) male, 1 reported as transgender, and 1 self-identified. All students were enrolled in Introductory Psychology classes and earned credit through their participation in this study. The majority of the students were in their first year (29%), with the rest in their second year (21%), third year (15%), fourth year (13%) and other (4%). The majority of the sample reported a cumulative college grade point average (GPA) in the range of 3.01–4.00 (67%). We did not collect age, ethnicity, or other demographic information to limit indirect identifiers as requested by the IRB. Students were compensated for participation with research credit. Materials We measured four major categories of variables: student learning experience, pandemic behavioral changes, class and instructor perceptions, and personal characteristics (stress, coping, self-efficacy, and personality). Descriptive data and internal reliability information for all measures are listed in Table 1. Table 1. Descriptive Statistics and Internal Reliability for Major Study Variables. Item α Mean SD Min Max Learning – 3.33 0.69 1.00 5.00 Enjoyment – 3.00 0.79 1.00 5.00 Course Quality .88 4.19 0.64 2.33 5.00 Class Attitude .79 2.42 0.66 1.00 4.40 Class Effort .65 2.73 0.78 1.00 5.00 Instructor Effort .84 5.93 0.92 1.00 7.00 Class Behavior Change .80 3.55 0.75 1.57 5.93 Professor Behavior Change .81 4.57 0.72 2.20 7.00 Personal Behavior Change .72 3.20 0.71 1.00 5.00 Health Behavior Change .79 3.19 0.72 1.22 4.89 Perceived Stress Scale .86 31.41 6.63 14.00 48.00 Positive Coping .73 23.43 5.17 9.00 36.00 Negative Coping .64 19.37 4.66 10.00 35.00 Conscientiousness – 5.41 1.29 1.00 7.00 Agreeable – 4.91 1.17 1.00 7.00 Neuroticism – 4.02 1.41 1.00 7.00 Openness – 4.99 1.49 1.00 7.00 Extraversion – 3.96 1.65 1.00 7.00 Note: α = internal reliability as measured by Cronbach's alpha. Sample size = 272. Learning Experience We used four measures of learning experience. We measured student perceptions of learning by having students rate how much they learned in all their classes for the current term. We provided space for five classes and a scale ranging from 1 (none at all) to 5 (a great deal). We also asked students how much they enjoyed all their classes using the same scale. Given classes vary in quality and student enjoyment, we did not expect ratings to be correlated and, consequently, did not compute internal reliability statistics for these measures. We measured Course Quality with six items (e.g., Canvas material). Students used a 5-point scale ranging from 1 (terrible) to 5 (excellent). We measured class attitudes and perceptions of classes during the term by asking students how they felt toward their classmates, instructor, and learning engagement, as well as their related experiences of happiness and optimism relating to their learning experiences, using a scale ranging from 1 (none at all) to 5 (a great deal). Pandemic Behavior Changes We used items modified from previous research to measure change in four major categories. Students indicated the extent to which each of 14 behaviors (e.g., class preparation) changed during the pandemic to create a measure of Class Behavior Change, using a scale ranging from 1 (much lower) to 7 (much higher). Seven items measured how Personal Behavior Change (e.g., television watching) occurred during the pandemic with a scale ranging from 1 (much less) to 5 (much more). Nine items measured how Health Behavior Change (e.g., biking, yoga) occurred during the pandemic with a scale ranging from 1 (much less) to 5 (much more). We measured perceptions of Professor Behavior Change using 10 items from the Teacher Behavior Checklist (Keeley et al., 2006), using a scale ranging from 1 (much lower) to 7 (much higher). Class and Instructor Perceptions Items derived from the American Psychological Association's Introductory Psychology Initiative measured student and instructor classroom behaviors (Richmond et al., 2021). We measured student class effort by asking how often they viewed slideshows, took notes, attended class prepared, interacted in small groups, asked classmates a question, and asked instructors a question. Students used a 5-point scale ranging from 1 (never) to 5 (always). To measure instructor effort, we asked students to think of their favorite class's instructor and rate them on five items: communicates the goals of the course, communicates the purpose of course activities, measures learning in different ways, respects students that have diverse backgrounds, and creates a supportive environment using a 7-point Likert-type scale from 1 (strongly disagree) to 7 (strongly agree). Personal Factors Students reported their self-efficacy for online learning by selecting where they learned best: in online classes, in-person classes, or no difference between the modalities. Students fell into two clear groups. The first group (n = 151) who reported they did not learn well in online classes were coded to have low self-efficacy for online learning. Students who reported being able to learn equally well online and in-person were coded as having high self-efficacy for online learning (n = 103). Only 13 students said they did not learn well in in-person classes and were merged into the previous category. We measured perceptions of stress using the Perceived Stress Scale (PSS; Cohen et al., 1983). This ten-item scale asked students to identify the degree to which they experienced a number of different stressful feelings (e.g., How often have you felt that things were not going your way?). Students responded using a scale ranging from 1 (never) to 5 (often). We assessed coping styles using the COPE Inventory (Carver et al., 1989). Students indicated the extent they used each of 60 different behaviors (e.g., I talk to someone about how I feel) using a scale ranging from 1 (I usually don’t do this at all) to 4 (I usually do this a lot). We created a positive coping and negative coping composite as suggested by past research (e.g., Kapsou et al., 2010) summing subscales primarily positive (e.g., seeking support) or negative (e.g., substance use) in nature. Finally, we used a short measure of personality, the Ten-Item Personality Inventory (TIPI, Gosling et al., 2003). This ten-item measure includes two items to assess each of the five major aspects of personality: conscientiousness, agreeableness, neuroticism, openness, and extraversion. Five items are reverse scored and participants used a seven-item scale ranging from 1 (disagree strongly) to 7 (agree strongly). The authors caution against calculating reliability. Procedure We posted a link and invitation to a Qualtrics survey on the department participant pool (SONA software). Students had different studies to select from to satisfy a class research requirement. Those who picked the study first read an informed consent form. The entire survey, including the order of presentation and measures not used in this report, is available on https://osf.io/zhwtf/?view_only=e66ebc5968214358adefa627cf8236e0. The study took approximately 20 minutes. Results Associations Between Factors Related to Learning We first explored the associations between variables in the study that have previously been independently associated with perceived learning. Correlations are shown in Table 2. We found evidence supporting most previously established relationships showing an important network of linkages between variables. Students with higher levels of Class Effort reported learning more, r(247) = .20, p = .002, and had more positive Class Attitudes, r(247) = .19, p = .003. We found similar positive relationships between Instructor Effort and all learning experiences including enjoyment of class. For example, the students’ rating of the instructor was significantly correlated with the students’ Class Attitudes, r(254) = .33, p < .001. Table 2. Correlations Between Key Study Variables. Measures Class Behavior Change Professor Behavior Change Personal Behavior Change Health Behavior Change Class Attitude Enjoyment Learning Course Quality Class Effort .183 -.014 -.015 -.071 .176 .190 .185 .109 Instructor Effort .184 .241 .055 -.065 .240 .328 .298 .512 Per. Stress Scale -.281 .072 .051 .173 -.371 -.231 -.288 -.041 Positive Coping .057 .239 -.025 -.171 .249 .220 .197 .226 Negative Coping -.221 .087 .135* .063 -.212 -.090 -.267 -.096 p < 0.05. p < 0.01. A multivariate analysis of variance (MANOVA) tested if students’ self-efficacy related to changes in their learning using the four learning composites. Means and standard deviations for all main variables separated by level of self-efficacy are available on the OSF page. We found significant main effects for self-efficacy on learning, Hotelling's Trace F(4,248) = 20.90 , p < .001, η2 = .25, reflecting a small effect size (Cohen, 1988). Tests of between subject effects showed a significant main effect for self-efficacy on Learning, F(1,252) = 33.74, p < .001, η2 = .12, Enjoyment, F(1,252) = 35.98, p < .001, η2 = .13, Class Quality, F(1,252) = 13.90 , p < .001, η2 = .05, and Class Attitudes, F(1,252) = 75.31 , p < .001, η2 = .23. Students who saw both modalities as equivalent for their learning did better on all counts. Does Self-Efficacy Moderate the Relationship Between Stress, Coping, and Learning? We tested moderation using a hierarchical regression model with self-efficacy as a reference variable and moderator for each independent variable of interest. We included an interaction term for self-efficacystress, self-efficacypositive coping, and self-efficacynegative coping. Self-efficacy did not show a moderating effect on the relationship between stress and coping, and learning. The first step of the model predicted 22% of the variance in learning, F(4,241) = 16.87, p < .001, with self-efficacy (b = .29, SE = 0.08, p < .001, positive coping (b = .21, SE = 0.01, p = .001) and negative coping (b = −0.28, SE = 0.01, p < .001) all significant. Self-efficacy was not significant in the second step, and neither stress nor any of the interaction terms were significant. It is possible that the single regression model does not capture the nuance of the relationship between these variables. To test if self-efficacy moderates the stress-learning relationship with coping as a significant mediator, we utilized Hayes’ PROCESS Model 5 to examine self-efficacy as a moderator while negative and positive coping were held as mediators. The conditional process overall model showed self-efficacy was not a significant moderator (b = -.55, SE = 0.67, p = .42, CI = −1.877 to 0.777), however positive coping (b = .028, SE = 0.01, p < .001, CI = 0.012–0.044) and negative coping (b = −0.043, SE = 0.01, p < .001, CI = −0.061 to −0.024) both predicted learning. Importantly, the style of coping had a commensurate impact on learning such that when negative strategies were employed, learning outcomes were more negative (and vice versa). Does Coping Mediate the Relationship Between Stress and Learning? To focus on the effects of coping exclusively, we conducted a hierarchical regression model utilizing Model 4 PROCESS macro version 3.5 (Hayes, 2018) in SPSS to test if positive and negative coping are mediators of the stress and learning relationship. The overall model showed no significant direct effect between stress and learning (b = -.000, SE = 0.12, p = .99, CI = −0.024 to 0.024), once positive coping (b = .03, SE = 0.01, p < .001, CI = 0.014–0.048) and negative coping (b = −.048, SE = 0.01, p < .001, CI = −0.07 to −0.03) were accounted for; coping predicted learning, thus mediating the relationship between stress and learning, as hypothesized. Additionally, positive coping (b = .39, SE = 0.08, p < .001, CI = 0.24–0.54) and negative coping were predicted by stress (b = 0.49, SE = 0.07, p < .001, CI = 0.35–0.62). Does Self-Efficacy Predict Unique Variance in Self-Reported Experiences of Learning? We used a hierarchical multiple regression analysis to test if self-efficacy significantly predicted self-reported learning, and if it did so more than personal characteristics and behaviors. We entered five personality variables, perceived stress, and positive and negative coping in the first block. We then entered student behaviors and ratings of the professor as a block in a second step. Finally, we entered self-efficacy in the third step. Step 1 predicted a significant portion of the variance, R2 = .16, F (8, 237) = 5.56, p < .001. Positive coping (β = .19, p = .004), negative coping (β = -.23, p = .003), and perceived stress (β = -.19, p < .019) were significant predictors of learning. Step 2 accounted for an additional 6% of the variance, F (2,235) = 9.21, p < .001, with instructor ratings significant (β = .23, p < .001). Step 3 accounted for an additional 4% of variance, F (1,234) = 13.30, p < .001, with self-efficacy a significant predictor of learning (β = .22, p < .001). Discussion This study examined changes in student learning behaviors during the first year of the COVID-19 pandemic, with a focus on a potential moderator (self-efficacy) and mediator (coping) of the stress and perceived learning relationship. We found significant positive relationships between self-efficacy, stress, coping and perceived learning, especially in attitudes toward class and ratings of instructors. Similarly to recent work (Bathallath & Brahimi, 2022; Nuere et al., 2022), this study provides further evidence that perceived stress and coping are significantly related to learning experiences, evidenced by our correlational results, and in the role of self-efficacy and coping in perceived learning (Gurung & Stone, 2020). These results provide a strong incentive for more robust examination of potential interventions related to these factors, particularly as the COVID-19 pandemic continues. As predicted, we found significant variation in our measures as a function of self-efficacy, which also predicted a unique portion of variance in learning experiences, consistent with previous pandemic studies of learning (Gurung & Stone, 2020). We found that self-efficacy predicted perceived learning, but we did not find evidence suggesting that self-efficacy moderates the relationship between stress and coping. This non-significant finding is in contrast to the strong predictive value of self-efficacy predicted by previous work (Bandura, 2013). It is possible that pandemic-related stress was strong enough to minimize the effect of student beliefs about their success in remote modalities with coping mechanisms. In fact, comparing the descriptive data on the PSS against typical scores for individuals in the same age range from before the pandemic, support this possibility. Although psychological research suggests self-efficacy, in many domains, is responsible for the type and valence of student strategies when managing highly stressful situations, it may not be able to compete with coping as a moderator between stress and learning (Bathallath & Brahimi, 2022). Coping was significantly related to perceived learning in every analysis, suggesting students could benefit from additional opportunities designed to develop positive approaches to coping. Strongly supporting recent research (Nuere et al., 2022), our results suggest useful coping strategies can influence students’ perceptions of their educational experiences. They also suggested that employing negative strategies were associated with negative outcomes, while positive strategies were associated with positive outcomes. This is another reason that we should attempt to provide students with more opportunities to learn positive coping mechanisms, particularly for populations most vulnerable to negative strategies (Siira et al., 2022). Coping was also related to a number of other student experiences and behaviors. These results imply that coping mechanisms are important for socio-emotional factors related to students’ connection with school and classes, happiness, and overall optimism about their education, while student alignment within modality is crucial to performance-based measures such as learning outcomes. More research is factoring in the role of student behaviors and experiences (Richmond et al., 2021) and it clear this approach provides greater insight into what can aid student learning. This study replicated and extended previous work to provide an understanding of the multiple changes in attitudes and behaviors in response to learning during the COVID-19 pandemic (Gonzalez-Ramirez et al., 2021; Keržič et al., 2021; Kim et al., 2021a; Schreiber, 2021). Teaching and learning has continued to change throughout the COVID-19 pandemic, and it is likely that higher education will continue to utilize remote methods of learning, both to address safety concerns in possible future global health threats, but also to provide opportunities for students who may be otherwise limited in attending regular face-to-face classes (Daniela & Visvizi, 2022). By taking into consideration the high levels of stress that students self-report regarding living and learning through a global pandemic, we are more certain that factors related to learning outcomes are correlated with coping and other understudied variables in teaching and learning research. Limitations and Future Directions There are three major limitations to this study. First, all data are cross-sectional, preventing tests of causality. While PROCESS modeling can be misinterpreted to address causality by virtue of the way models are drawn and temporal precedence, this is not the reality. Both perceived stress and self-efficacy can be strong self-fulfilling prophecies, and this cannot be captured without measurements taken at multiple points during the term. A second limitation is the lack of objective measures of learning within the study. Relying on self-reported data does not provide a full picture of learning in the COVID-19 pandemic. It might capture more subjective experiences of students’ learning outcomes, which may give greater insight into the effect of stress and self-efficacy on their experiences of learning. Our measure of self-efficacy was only one item and additional work using multi-item scales would provide a more valid measure of the concept. Finally, we did not collect demographic information regarding age, ethnicity, and other personal identity factors, which may have resulted in lack of representation across the sample. The information collected suggests the sample is somewhat lopsided, with the majority of the population being female students in their first or second year of college. These demographic data certainly impact the magnitude of the generalizability of these findings. Future research should first use more robust measures of self-efficacy. Our measure was a single item question and it is possible that students conflated online learning and remote learning. A multi-item measure will increase the construct validity of the self-efficacy measure. Research also needs to include the collection of demographic data to show differences across race, ethnicity, and other social groups, and the addition of objective measures of learning. It would be prudent to also consider using a less stressful time (i.e., just regular amounts of stress) as the pandemic caused an unusually high amount of stress, which resulted in the PSS potentially overshadowing any effect of self-efficacy. Students are no strangers to stress throughout college, with or without COVID-19. These factors have a unique relationship across modalities that future research should explore in more detail to give a clearer picture of the mechanisms that drive strategy selection. Follow-up studies can re-examine these factors outside of the context of the pandemic and provide evidence of the importance of modality to students. It is clear that students do not always get what they want with respect to modality even during times of relative normalcy, and the impact of modality in those times should continue to be examined fully. These are just a few more avenues to explore as we continue to mount evidence that success begins with believing one can even try. Author Biographies Regan A. R. Gurung, Ph.D., is an Associate Vice Provost & Executive Director for the Center for Teaching and Learning at Oregon State University, Director of the General Psychology Program, and Professor of Psychology. He is the author/co-author/editor/co-editor of 15 books, most recently Study like a Champ (with John Dunlosky) and over 125 peer reviewed articles. He is a Fellow of APA, APS, and past President of Psi Chi (International Honor Society in Psychology) and the Society for the Teaching of Psychology. He is a founding co-editor of the Scholarship of Teaching and Learning in Psychology, and winner of the APF Charles L. Brewer Award for Distinguished Teaching in Psychology. Stephanie M. Byers, M.A., is a Psychology PhD student at Oregon State University whose research bridges teaching and learning topics with social psychological topics. An enthusiastic teacher and researcher, she strives to contribute to research on topics and phenomena that can be applied to the classroom to facilitate effective teaching and learning practices. Her current work investigates academic identity, persistence in academic tasks, and the variables involved in transfer student success. Jor Grapentine, M.A., is a Psychology PhD student at Oregon State University. Their research includes trans health and wellbeing, as well as teaching and learning. Arianna Stone, M.S., is a member of the faculty in the Behavioral Sciences Department at Western Oregon University and a third year PhD student at Oregon State University currently on hiatus as she welcomes home her third child. Her research work is focused in motivation, specifically in persistence behaviors and burnout in academic contexts. The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article. ORCID iD: Regan A. R. Gurung https://orcid.org/0000-0002-3542-4378 ==== Refs References Bamber M. D. Schneider J. K. (2022). College students’ perceptions of mindfulness-based interventions: A narrative review of the qualitative research. Current Psychology: A Journal for Diverse Perspectives on Diverse Psychological Issues, 41 (2 ), 667–680. 10.1007/s12144-019-00592-4 Bandura A. (2013). The role of self-efficacy in goal-based motivation. In Locke E. A. Latham G. P. (Eds.), New developments in goal setting and task performance (pp. 147–157). Routledge/Taylor & Francis Group. Bathallath J. Brahimi T. (2022). Stress, anxiety, and depression among students and employees during the pandemic: A view from the KSA. In Daniela L. Visvizi A. (Eds.), Remote learning in times of pandemic: Issues, implications, and best practices (pp. 183–195). Routledge. Bogdanov M. Nitschke J. P. LoParco S. Bartz J. A. Otto A. R. (2021). Acute psychosocial stress increases cognitive-effort avoidance. Psychological Science, 32 (9 ), 1463–1475. 10.1177/09567976211005465 34464216 Browning M. H. E. M. Larson L. R. Sharaievska I. Rigolon A. McAnirlin O. Mullenbach L. Cloutier S. Vu T. M. Thomsen J. Reigner N. Metcalf E. C. D'Antonio A. Helbich M. Bratman G. N. Alvarez H. O. (2021). Psychological impacts from COVID-19 among university students: Risk factors across seven states in the United States. PLoS ONE, 16 (1 ). 10.1371/journal.pone.0245327 Carver C. S. Scheier M. F. Weintraub J. K. (1989). Assessing coping strategies: A theoretically based approach. Journal of Personality and Social Psychology, 56 , 267–283. 10.1037/0022-3514.56.2.267 2926629 Cohen J. (1988). Statistical power analysis for the behavioral sciences. Lawrence Erlbaum Associates. Cohen S. Kamarck T. Mermelstein R. (1983). A global measure of perceived stress. Journal of Health and Social Behavior, 24 , 386–396. 10.2307/2136404 Daniel D. B. Poole D. A. (2009). Learning for life: An ecological approach to pedagogical research. Perspectives on Psychological Science, 4 (1 ), 91–96. 10.1111/j.1745-6924.2009.01095.x 26158839 Daniela L. Visvizi A. (2022). Introduction: Remote learning as a mode of distance learning. In Daniela L. Visvizi A. (Eds.), Remote learning in times of pandemic: Issues, implications, and best practices (pp. 1–10). Routledge. Dunlosky J. Rawson K. A. Marsh E. J. Nathan M. J. Willingham D. T . (2013). Improving students’ learning with effective learning techniques: Promising directions from cognitive and educational psychology. Psychological Science in the Public Interest, 14 (1 ), 4–58. 10.1177/1529100612453266 26173288 Fox K. Bryant G. Lin N. Srinivasan N. (2020). Time for class – COVID-19 edition part 1: A national survey of faculty during COVID-19. Tyton Partners and Every Learner Everywhere. Geier M. T. (2022). The teacher behavior checklist: The mediation role of teacher behaviors in the relationship between the students’ importance of teacher behaviors and students’ effort. Teaching of Psychology, 49 (1 ), 14–20. 10.1177/0098628320979896 Giuntella O. Hyde K. Saccardo S. Sadoff S. (2021). Lifestyle and mental health disruptions during COVID-19. PNAS Proceedings of the National Academy of Sciences of the United States of America, 118 (9 ), 1–9. 10.1073/pnas.2016632118 Gonzalez-Ramirez J. Mulqueen K. Zealand R. Silverstein S. Reina C. BuShell S. Ladda S. (2021). Emergency online learning: College students’ perceptions during the COVID-19 pandemic. College Student Journal, 55 (1 ), 29–46. Gori A. Topino E. Di Fabio A. (2020). The protective role of life satisfaction, coping strategies and defense mechanisms on perceived stress due to COVID-19 emergency: A chained mediation model. PLoS ONE, 15 (11 ). 10.1371/journal.pone.0242402 Gosling S. D. Rentfrow P. J. Swann W. B. Jr. (2003). A very brief measure of the Big Five personality domains. Journal of Research in Personality, 37 , 504–528. 10.1037/t07016-000 Gruenewald T. Wang D. (2019). Stress and health. In Revenson T. A. Gurung R. A. R. (Eds.), Handbook of health psychology (pp. 234–246). Routledge. Gurung R. A. R. Hackathorn J. (2018). Ramp it up: A call for more research in introductory psychology. Teaching of Psychology, 45 (4 ), 302–311. 10.1177/0098628318796413 Gurung R. A. R. Mai T. Nelson M. Pruitt S. (2022). Predicting learning: Comparing study techniques, perseverance, and metacognitive skill. Teaching of Psychology, 49 (1 ), 71–77. 10.1177/0098628320972332 Gurung R. A. R. Plaza D. (2023). Onwards to better: The future of higher education in a post-pandemic world. Stylus. Gurung R. A. R. Stone A. M. (2020). You can’t always get what you want and it hurts: Learning during the pandemic. Scholarship of Teaching and Learning in Psychology. 10.1037/stl0000236 Hayes A. F. (2018). Partial, conditional, and moderated mediation: Quantification, inference, and interpretation. Communication Monographs, 85 (1 ), 4–40. 10.1080/03637751.2017.1352100 Hicks L. J. Caron E. E. Smilek D. (2021). SARS-CoV-2 and learning: The impact of a global pandemic on undergraduate learning experiences. Scholarship of Teaching and Learning in Psychology. 10.1037/stl0000250 Kapsou M. Panayiotou G. Kokkinos C. M. Demetriou A. G. (2010). Dimensionality of coping: An empirical contribution to the construct validation of the Brief-COPE with a Greek-speaking sample. Journal of Health Psychology, 15 (2 ), 215–229. 10.1177/1359105309346516 20207665 Keeley J. Smith D. Buskist W . (2006). The teacher behaviors checklist: Factor analysis of its utility for evaluating teaching. Teaching of Psychology, 33 (2 ), 84–91. https://doi-org/10.1207/s15328023top3302_1 Keržič D. Alex J. K. Pamela Balbontín Alvarado R. Bezerra D. D. S. Cheraghi M. Dobrowolska B. Fagbamigbe A. F. Faris M. E. França T. González-Fernández B. Gonzalez-Robledo L. M. Inasius F. Kumar Kar S. Lazányi K. Lazăr F. Machin-Mastromatteo J. D. Marôco J. Marques B. P. Mejía-Rodríguez O. , … Aristovnik A. (2021). Academic student satisfaction and perceived performance in the e-learning environment during the COVID-19 pandemic: Evidence across ten countries. PLoS ONE, 16 (10 ), e0258807. 10.1371/journal.pone.0258807 34669757 Kim A. S. N. Khan S. A. Carolli A. Park L. (2021a). Investigating teaching and learning during the coronavirus disease 2019 pandemic. Scholarship of Teaching and Learning in Psychology. 10.1037/stl0000296 Kim Y. Yu S. L. Shin J. (2021b). How temptation changes across time: Effects of self-efficacy for self-regulated learning and autonomy support. Educational Psychology. 10.1080/01443410.2021.2009774 Lederer A. M. Hoban M. T. Lipson S. K. Zhou S. Eisenberg D. (2021). More than inconvenienced: The unique needs of U.S. college students during the COVID-19 pandemic. Health Education & Behavior, 48 (1 ), 14–19. 10.1177/1090198120969372 33131325 Means B. Neisler J. , with Langer Research Associates. (2020). Suddenly online: A national survey of undergraduates during the COVID-19 pandemic. Digital Promise. Tyton Partners and Every Learner Everywhere. www.everylearnereverywhere.org/resources Nuere S. Suz A. A. Alvarez L. D. (2022). Reflections on the adaptation to the COVID-19 pandemic in higher education. In Daniela L. Visvizi A. (Eds.), Remote learning in times of pandemic: Issues, implications, and best practices (pp. 113–129). Routledge. Richmond A. S. Boysen G. A. Hudson D. L. Gurung R. A. R. Naufel K. Z. Neufeld G. Landrum R. E. Dunn D. S. Beers M . (2021). The introductory psychology census: A national study. Scholarship of Teaching and Learning in Psychology, 7 (3 ), 163–180. https://doi-org/10.1037/stl0000277 Rosli M. S. Saleh N. S. (2022). Technology enhanced learning acceptance among university students during COVID-19: Integrating the full spectrum of self-determination theory and self-efficacy into the technology acceptance model. Current Psychology: A Journal for Diverse Perspectives on Diverse Psychological Issues. 10.1007/s12144-022-02996-1 Sawyer K. Dunlosky J. (2019). How the learning sciences can inform cognitive psychology. In Dunlosky J. Rawson K. (Eds.), The Cambridge handbook of cognition and education (pp. 17–34). Cambridge University Press. 10.1017/9781108235631.002 Schmid L. Drake C. Price A. (2021). Differences in health behaviors and outcomes for emerging adults in diverse post-secondary educational institutions: Lessons for targeting campus health promotion efforts. College Student Journal, 55 (3 ), 267–280. Schreiber W. B. (2021). Teaching in a pandemic: Adapting preparations for asynchronous remote learning using three evidence-based practices. Scholarship of Teaching and Learning in Psychology, 8 (2 ), 106–112. 10.1037/stl0000208 Siira V. Petäjäniemi M. Lutovac S. Kaasila R. (2022). The role of mind-body bridging-based university psychology course for students’ well-being. Nordic Psychology. 10.1080/19012276.2022.2159867 Wigfield A. Eccles J. S. (2000). Expectancy-value theory of achievement motivation. Contemporary Educational Psychology, 25 (1 ), 68–81. 10.1006/ceps.1999.1015 10620382 Yang C. Chen A. Chen Y. (2021). College students’ stress and health in the COVID-19 pandemic: The role of academic workload, separation from school, and fears of contagion. PLoS ONE, 16 (2 ). 10.1371/journal.pone.0246676 Yang X. Xiong Z. Li Z. Li X. Xiang W. Yuan Z. L. (2020). Perceived psychological stress and associated factors in the early stages of the coronavirus disease 2019 (COVID-19) epidemic: Evidence from the general Chinese population. PLoS ONE, 15 (12 ). 10.1371/journal.pone.0243605
PMC009xxxxxx/PMC9933813.txt	==== Front Clin Oral Investig Clin Oral Investig Clinical Oral Investigations 1432-6981 1436-3771 Springer Berlin Heidelberg Berlin/Heidelberg 36795249 4900 10.1007/s00784-023-04900-y Research Possible sleep bruxism and biological rhythm in school children Marceliano Camila Rita Vicente Gavião Maria Beatriz Duarte [email protected] grid.411087.b 0000 0001 0723 2494 Department of Health Sciences and Pediatric Dentistry, Piracicaba Dental School, University of Campinas (UNICAMP), Avenida Limeira, 901, Piracicaba, SP 13414-903 Brazil 16 2 2023 2023 27 6 29792992 30 6 2022 3 2 2023 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Abstract Objective To verify whether children with possible sleep bruxism (PSB) had alterations in biological rhythm and to explore the possible factors involved, such as sleep characteristics, screen time, breathing, sugary food consumption, and clenching teeth during wakefulness reported by parents/guardians. Methodology Data were collected through online interviews with 178 parents/guardians of students aged 6 to14 years from Piracicaba, SP, BR, when the BRIAN-K scale was answered, which is composed of four domains (1) sleep; (2) daily routine activities; (3) social behavior; (4) eating; questions about predominant rhythms (willingness, concentration, and change day to night). Three groups were formed: (1) without PSB (WPSB), (2) with PSB sometimes (PSBS), and (3) with PSB frequently (PSBF). Results Sociodemographic variables were similar between groups (P > 0.05); the total value of the BRIAN-K was significantly higher for the PSBF group (P < 0.05); the first domain (sleep) presented significantly higher values for the PSB groups (P < 0.05); no significant difference for other domains and predominant rhythms occurred (P > 0.05). The involved factor that differed between groups was clenching teeth, as the number of children with PSBS was significantly higher (χ2, P = 0.005). The first domain of the BRIAN-K (P = 0.003; OR = 1.20), and clenching teeth (P = 0.048; OR = 2.04) were positively associated with PSB. Conclusion Difficulties in maintaining sleep rhythm and clenching teeth during wakefulness reported by parents/guardians may determine a greater chance to increase the frequency of PSB. Clinical relevance Good sleep seems to be important to maintain a regular biological rhythm and may reduce the frequency of PSB in the 6–14 age group. Supplementary Information The online version contains supplementary material available at 10.1007/s00784-023-04900-y. Keywords Sleep bruxism Circadian rhythm Children Bruxism Pediatric dentistry http://dx.doi.org/10.13039/501100003593 Conselho Nacional de Desenvolvimento Científico e Tecnológico Process 134016/2019-0 Marceliano Camila Rita Vicente http://dx.doi.org/10.13039/501100002322 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Finance code 001 Marceliano Camila Rita Vicente issue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction Bruxism consists of masticatory muscle activities that occur during sleep or wakefulness, qualifying it as sleep and awake bruxism, respectively, which in turn are different behaviors [1]. The muscle activity in sleep bruxism is characterized as rhythmic (phasic) or nonrhythmic (tonic) and in awake bruxism as repetitive or sustained tooth contact and/or by bracing or thrusting of the mandible); both are not a movement disorder in otherwise healthy individuals. Moreover, sleep bruxism is not considered a sleep disorder [1]. Currently, it is conceptualized that bruxism is regulated centrally, not peripherally, that is, anatomical factors, such as characteristics of occlusion and dental articulation, are not causal factors [1, 2]. Thus, the etiology is multifactorial and involves complex processes that are not necessarily related to specific sleep correlates or to teeth contact [1–3]. Awake bruxism can be associated with psychosocial factors and psychopathology symptoms [3]. As the central nervous system plays a role in the pathogenesis of sleep bruxism, a genetic contribution of brain neurotransmitters such as dopamine and serotonin has been suggested in the etiology of sleep bruxism [4]. In fact, the involvement of the serotonergic pathway in the pathogenesis of sleep bruxism was recently evidenced [5]. The prevalence of sleep bruxism in children and adolescents varies widely between 3.5% and 40.6%, as defined by different diagnostic methods (interviews, parent reports, clinical assessment, objective polysomnography, and electromyographic assessment) [6]. The prevalence of awake bruxism due to difficult diagnosis is estimated only in adults, ranging from 5.0 to 31.0% [7]. Due to the limitation of diagnostic methods, sleep bruxism and awake bruxism are classified as possible, probable and definite [2]. Possible bruxism is based on positive self-report, through a questionnaire and/or anamnesis. In the meantime, the probable bruxism should be based on a positive clinical examination (such as tooth wear, muscle pain or fatigue, indentations in the mucosa of the tongue or cheek) with or without positive self-report. For definite sleep bruxism, a positive polysomnographic record is required; definite awake bruxism should be based on the graphic record of the electromyogram, preferably combined with the so-called momentary ecological assessment methodology, which allows obtaining a true estimate, among others, of the frequency of dental contacts during wakefulness; these indicators may or may not be associated with self-report or positive clinical examination [1, 3]. In fact, self-reported of possible sleep bruxism is considered reliable, although theoretically difficult as the individual is asleep while performing the activity, but informants can be interrogated, and for children, their parents/guardians are considered eligible and confident proxies. According to Kuhn and Türp [8], behavioral problems, sleep conditions, excessive use of digital media and inappropriate eating habits can be considered risk factors for bruxism in children and adolescents. In fact, children with sleep bruxism can have poor sleep quality, sleeping less than 8 h a night [9]. Light and sound stimuli, direct and indirect, can be considered predisposing factors to bruxism in children [10]. The association of inappropriate eating habits mainly added sugar, with excessive use of media may trigger the onset of sleep bruxism [11], since they can alter dopamine neurotransmission, interfering with the rewarding effects of food [12] and videogame playing [13]. The COVID-19 pandemic, which started in 2020, determined a new factor possibly influencing sleep due to mandatory social isolation at home, as a public health measure to mitigate the population's infection [14, 15]. Such a measure could change the lifestyle of individuals [16] with possible negative consequences for well-being, therefore influencing the sleep/wake cycle and circadian rhythms [17, 18]. Furthermore, in general, the psycho-emotional state worsened with the COVID-19 pandemic, intensifying, or triggering adverse stomatognathic conditions, such as orofacial pain due to increased bruxism and TMD symptoms [19, 20]. Specifically in children, a significant increase in possible sleep bruxism and sleep disorders was observed during COVID-19 pandemic compared to time before pandemic, influenced by the mothers’ lower education, greater access to electronic devices, and the occurrence of sleep disorders [21]. In this context, biological rhythm could play a role in the etiology of bruxism [9, 22]. Biological rhythm consists of the physiological and behavioral expression that contains a regular periodicity, for example, the secretion of hormones, the sleep–wake cycles, and the regularity of feeding [23, 24]. Disruptions in the biological rhythm may cause emotional and behavioral changes and negative consequences on sleep–wake rhythm [24, 25]. Considering the central regulation of sleep bruxism [1, 2], the variables responsible for the biological rhythm disturbance in children [22, 26], the social, economic, and psycho-emotional factors affected by COVID-19 pandemic [16–18, 21], it is noteworthy to explore the multifactorial aspects involved in sleep bruxism, to provide new insights for clinical and research approaches. Based on those premises, this study aimed to verify whether children with sleep bruxism presented changes in their biological rhythm related to sleep, daily routine activities, social behavior and eating, and to explore the possible factors involved. Methodology This was a cross-sectional observational study carried out with a convenience sample composed of 178 parent/guardian-child dyads. It was conducted during the period of the COVID-19 pandemic, from October 2020 to November 2021. Ethical aspects The project was submitted to the Research Ethics Committee (CEP) of the Piracicaba Dental School, University of Campinas (FOP-UNICAMP) and approved with CAAE opinion number 3618619.6.0000.5418. The parents/guardians signed the Free and Informed Consent Term on the Google forms digital platform, as detailed below. Study design First, the São Paulo State Department of Education of Piracicaba City, SP, Brazil, was contacted to obtain authorization for access the state schools. After this step, the directors and coordinators were contacted by telephone to obtain authorization to enter the schools and send the documents related to the research. Ultimately, a total of 5 participating schools were obtained. Then, the respective directors were asked to provide the contacts of children/adolescents of both sexes, aged 6 to 14 years, and their parents/guardians; the accesses of the WhatsApp groups of the classrooms were obtained. Following, parents/guardians of children received an invitation to participate in the study and a link to access the TCLE on the Google forms digital platform, to indicate whether they agreed to participate (Fig. 1).Fig. 1 Flowchart of experimental design Those who agreed to participate signed the consent form digitally and provided personal contacts, as asked in the invitation. Thus, a 20-min online interview with parents/guardians was asked and the day and time choose by them were informed to the examiner. During this interview, the inclusion and exclusion criteria were considered, with the characteristics of the children obtained only from the parents' reports, since a medical report was not required. As inclusion criteria, children should be healthy, with normal cognitive development, as they should be enrolled at school in age-appropriate classes. Parents should be able to use computers or smartphone to participate the online interview. Exclusion criteria were children with mental retardation or psychiatric disorders, high complexity systemic problems (diabetes, hypertension, kidney problems, and/or heart problems) and parents who would not understand or could not answer the questions. The online interview was characterized as semi-structured and divided into three moments: (1) anamnesis; (2) biological rhythm assessment, and (3) food diary reminder. The interview was recorded, with the respective agreement by the parents/guardian. The answers were verbally informed, and the video was saved on Google Drive.Anamnesis Parents/guardians verbally replied to the following information: personal data of the child and legal guardian, socioeconomic information (parents' education, marital status, professional status, family income), child’s medical history, presence or absence of menarche in girls, dental history (report of dental problems, information on oral hygiene, history of dental trauma and history of early loss of a tooth; type of dentition), child's weight and height to determine body mass index (BMI = weight/height2), and frequency of physical activities. In addition, the following information was obtained:Routine: child’s activities along the day, from the moment she/he woke up until bedtime during the 5 days of the week and during the weekends. Assessment of the place where the child rests: presence or absence of lights on in the child’s room during sleep, absence or presence of noise, with whom the child slept, the distance from the parent’s room, and whether the door was open or closed during sleep. Assessment of the use of technological means: device types to which the child had access (cell phones, tablets, computers, televisions, and video games) and the frequency of use during the total day (hours) were informed. Assessment of possible sleep bruxism [1]: three questions were addressed:Does your child grind his/her teeth during sleep? Answer: Never, sometimes, or always. How many times a week in the last month? (If answer 1 was positive) Answer: 1 time a week, 2 times a week, 3 times a week, or more than 4 times a week. When waking up in the morning or at night, your son/daughter has a locked jaw and/or pain in the jaw? Answer: yes or no Assessment of clenching:Has your child been clenching his teeth while awake? Answer: yes or no Sleep bruxism was classified as “possible” when there was a positive report from parents/guardians [1]. The frequency of bruxism was considered as “sometimes” when the child clenched teeth 1–2 times a week and “frequent” when the child clenched three or more times a week.(2) Biological rhythm The scale Biological Rhythms Interview for Assessment in Neuropsychiatry for Kids (BRIAN-K), translated into Portuguese by Berny et al. [26], has been used to measure biological rhythm disruption in Brazilian children and adolescents (Annex 2). This scale consists of 20 items, which were answered verbally by the parent/guardians. Items 1 to 17 correspond to children's difficulties in maintaining the biological rhythm in the last 15 days, in four domains: sleep, routine activities, social rhythm and eating pattern. Responses were categorized on the Likert scale from 0 to 3, with 0 = no difficulty; 1 = little difficulty; 2 = quite difficult; 3 = a lot of difficulty. Items 18, 19 and 20 assess whether the child displays a predominantly diurnal or nocturnal rhythm. Items 18 and 19 report, respectively, the part of the day parents/guardians feel that the child is more willing/active and more concentrated/productive to perform daily activities: 1 = morning; 2 = afternoon; 3 = at night; 4 = no specific shift. Item 20 informs whether the child switched from daytime to nighttime and the responses were categorized on a Likert scale from 1 to 4: 1 = never; 2 = rarely; 3 = almost always; 4 = always. In all domains, higher scores indicate greater difficulty in maintaining the biological rhythm. In case of doubts from parents/guardians, the researcher helped them in a standardized way, clarifying the item. (3) Food diary reminder Parents/guardians were asked to verbally inform the food record, which included a list of all food and drinks consumed within 24 h, that is, the day before the interview, describing the times and amounts, until the moment of the interview. For the present study, the frequency of sugary foods consumed per day was considered. Statistical analysis In the statistical analysis, the categorical variables were demonstrated by absolute and relative frequencies and numerical variables by means, standard deviations and medians, and intermediate quartiles. Normality was checked by using the Shapiro–Wilk test, homoscedasticity with the Levene’s test, and quantile–quantile-plot graphs (QQ-plot). Considering the presence or absence of possible bruxism, three groups were formed: (1) group without possible sleep bruxism; (2) group sometimes possible sleep bruxism; (3) group frequent possible sleep bruxism. One way ANOVA and Tukey test (α = 0.05) were used to assess the differences between the three groups of children with and without bruxism; for data without normal distribution, the Kruskal–Wallis test was used. Moreover, the Mann–Whitney test was applied for comparisons between two variables when indicated. The scores of the 17 questions of the BRIAN-K scale were summed, as well as the items of each domain, to obtain continuous scores. To verify the association between sociodemographic factors and those related to sleep characteristics, ordinal logistic regression models were constructed, with the dependent variable being the order of sleep bruxism, without, sometimes and frequent. First, the independent categorical variables whose P values in the bivariate analysis were less than 0.25 were selected, considering the inter- and intra-group comparisons. For continuous variables, a univariate ordinal logistic regression was constructed and those with P values less than 0.25 were also selected. After, the selected independent variables were included in two models of multivariate ordinal logistic regression. The first model included the sociodemographic characteristics as the independent variables, and the second model included those related to sleep characteristics, breathing, screen time, and clenching teeth during wakefulness reported by the parents/guardians as the independent variables. For this, the assumption of proportional odds was verified using the test of parallel lines, considering P values greater than 0.05, because the null hypothesis states that the slope coefficients in the model are the same across response categories (and lines of the same slope are parallel). Moreover, the assumption of multicollinearity was also verified, considering the variance inflation factor (VIF) less than 10 and tolerance around or less than 1, meaning that the independent variables were not correlated. Independent variables with a P value < 0.05 in the final models were found to be significantly associated with the order of possible sleep bruxism. The statistical software JAMOVI (version 2.3.9, retrieved from https://www.jamovi.org) was used, considering the significance level as alpha equal to 0.05. Results Table 1 shows the descriptive statistics for the sociodemographic variables. It was observed that the number of boys and girls was similar in the total sample, but the number of girls without possible sleep bruxism was significantly higher than boys (chi-square, P = 0.154). Moreover, the number of boys and girls who presented sometimes possible sleep bruxism or frequent possible sleep bruxism was similar (chi-square, P > 0.05). Height and weight did not show significant differences between groups. Only about 7% of the sample was underweight, differing significantly from the other weight status, while half of the sample was overweight or with obesity (49.44%). However, there was no significant difference in weight status between the children with or without possible sleep bruxism (chi-square, P > 0.05). Regarding the marital status and education of the mothers, there was a great variability, but most were married and had approximately 11 years of schooling (high school).Table 1 Sociodemographic characteristics of children and mothers and respective intra- and inter-group comparison Overall (N = 178) Without possible sleep bruxism (N = 101) Sometimes possible sleep bruxism (N = 41) Frequent possible sleep bruxism (N = 36) Between groups Test; P-values Children Sex [n (%)] Girls 99 (55.62) 64 (63.37) 19 (46.34) 16 (44.44) χ2 P = 0.153 Boys 79 (44.38) 37 (36.63) 22 (53.66) 20 (55.56) χ2 P = 0.134 P = 0.007 P = 0.639 P=0.505 Age (years) Mean (SD) 10.14 (1.97) 10.24 (1.98) 10.22 (2.04) 9.78 (1.88) ANOVA one way P = 0.524 Median (25%−75) 10.21 (8.42−11.92) 10.42 (8.42−11.83) 9.83 (8.50−12.08) 9.54 (8.33−11.43) Range 6.17−14.42 6.33−14.42 7.00−13.58 6.17−13.33 Weight (kg) Mean (SD) 41.53 (14.30) 41.44 (13.54) 43.12 (16.13) 39.97 (14.39) ANOVA one way P = 0.634 Median (25−75%) 38.95 (30.00−49.00) 39.00 (30.00−50.00) 39.00 (32.00−48.40) 38.45 (30.00−46.25) Range 19.00−84.00 21.00−82.00 19.00−80.00 21.00−84.00 Height (cm) Mean (SD) 1.43 (0.16) 1.43 (0.17) 1.43 (0.15) 1.40 (0.16) ANOVA one way P = 0.656 Median (25−75%) 1.42 (1.30−154) 1.43 (1.30−1.55) 1.40 (1.30−1.54) 1.40 (1.30−1.47) Range 1.05−1.82 1.05−1.82 1.17−1.80 1.15−1.75 BMI Mean (SD) 20.11 (4.75) 19.91 (4.22) 20.71 (5.75) 19.97 (5.00) Kruskal-Wallis P = 0.920 Median (25−75%) 19.45 (16.52−22.81) 19.29 (16.85−22.23) 19.51 (15.62−24.87) 19.66 (17.19−21.38) Range 11.72−37.10 12.49−33.14 12.43−34.63 11.72−37.10 Weight Status [n (%)] Underweight 12 (6.74) 6 (5.94) 2 (4.88) 4 (11.11) Fisher’s exact test P = 0.780 Normal weight 78 (43.82) 48 (47.52) 16 (39.02) 14 (38.89) Overweight 43 (24.16) 23 (22.77) 10 (24.39) 10 (27.78) Obesity 45 (25.28) 24 (23.76) 13 (31.71) 8 (22.22) χ2 P < 0.001 P < 0.001 P = 0.014 P = 0.014 Mothers Marital Status [n (%)] Single 42 (23.60) 23 (22.77) 9 (21.95) 10 (27.78) Fisher’s exact test P = 0.594 Married 87 (48.88) 55 (54.46) 16 (39.02) 16 (44.44) Divorced 21 (11.80) 10 (9.90) 7 (17.07) 4 (11.11) Widow 5 (2.81) 3 (2.97) 1 (2.44) 1 (2.78) Others 23 (12.92) 10 (9.90) 8 (19.51) 5 (13.89) χ2 P <0.0001 P <0.001 P=0.007 P <0.001 Educational Status [n (%)] 1° Degree 38 (21.30) 23 (22.77) 9 (22.00) 6 (16.67) χ2 P = 0.937 2° Degree 102 (57.30) 57 (56.44) 24 (58.54) 21 (58.33) Graduated 38 (21.30) 21 (20.79) 8 (19.51) 9 (25.00) P <0.001 P <0.001 P = 0.003 P = 0.005 Family Income1 [n (%)] < 1 21 (11.80) 14 (13.86) 3 (7.32) 4 (11.11) Fisher’s exact test P = 0.461 Between 1 to 2 68 (38.20) 41 (40.59) 17 (41.46) 10 (27.78) Between 3 to 4 51 (28.65) 27 (26.73) 14 (34.15) 10 (27.78) > 4 38 (21.35) 19 (18.81) 7 (17.07) 12 (33.33) P <0.001 P <0.001 P = 0.003 P = 0.261 SD standard deviation 1Wage per month–one wage = R$ 1100.00, approximately US$ 220.00 (during 2021, 1 US$ was approximately R$ 5.00) χ2 chi square corresponding P values in each column mean intra-group comparisons for proportions (χ2 adherence) The values for the BRIAN-K scale are shown in Table 2. For the overall sample, the difference occurred between children with frequent possible sleep bruxism and without possible sleep bruxism, the first ones with higher values. In the first domain, children with sometimes and frequent possible sleep bruxism showed significantly higher values than children without bruxism, and those did not differ from each other. For the other domains, no significant differences were found.Table 2 Descriptive data for BRIAN-K scores for the overall sample and groups and the respective comparisons BRIAN-K Overall (N = 178) Without possible sleep bruxism (N = 101) Sometimes possible sleep bruxism (N = 41) Frequent possible sleep bruxism (N = 36) Between groups Test; P values Total scale Questions 1–17 Mean (SD) 15.46 (9.32) 13.91 (8.25) A 16.76 (10.32) AB 18.38 (10.34) B ANOVA one way P = 0.0305 Tukey test P < 0.05 Median (25–75%) 13.00 (8.00–22.75) 11.00 (8.00–20.00) 14.00 (8.00–25.00) 16.50 (10.25–28.00) Range 1.00–43.00 1.00–42.00 1.00–35.00 2.00–43.00 First domain Sleep Mean (SD) 4.44 (3.50) 3.67 (3.21) A 5.39 (3.72) B 5.53 (3.61) B ANOVA one way P = 0.0035 Tukey test P < 0.05 Median (25–75%) 4.00 (2.00–6.00) 3.00 (1.00–6.00) 5.00 (3.00–8.00) 5.50 (3.00–8.00) Range 0.00–14.00 0.00–14.00 0.00–12.00 0.00–13.00 Second domain Routine activities Mean (SD) 4.49 (3.03) 4.37 (2.78) 4.15 (3.00) 5.25 (3.63) ANOVA one way P = 0.2269 Median (25–75%) 4.00 (2.00–7.00) 4.00 (2.00–6.00) 4.00 (2.00–6.00) 4.50 (2.00–8.00) Range 0.00–12.00 0.00–11.00 0.00–11.00 0.00–12.00 Third domain Social rhythm Mean (SD) 3.07 (2.64) 2.74 (2.28) 3.61 (3.11) 3.94 (2.93) Kruskal–Wallis P = 0.3173 Median (25–75%) 3.00 (1.00–5.00) 3.00 (1.00–4.00) 3.00 (1.00–5.00) 3.50 (1.00–5.25) Range 0.00–12.00 0.00–9.00 0.00–12.00 0.00–11.00 Fourth domain Eating pattern Mean (SD) 3.44 (3.05) 3.13 (2.82) 3.61 (3.05) 4.08 (3.59) ANOVA one way P = 0.2480 Median (25–75%) 3.00 (1.00–5.00) 2.00 (1.00–4.00) 3.00 (1.00–6.00) 3.50 (1.00–6.25) Range 0.00–12.00 0.00–12.00 0.00–10.00 0.00–12.00 Different superscript capital letters in columns mean significant differences between groups (respective lines in bold font) For predominant rhythm (Table 3), it was observed that for overall children, the most willing/active period was the afternoon, like the no specific shift. Inter- and intra-groups comparisons showed no significant differences in periods in which children were more willing/active. Regarding the periods in which children were more concentrated/productive, for the overall sample and children without possible sleep bruxism, the morning and afternoon periods were the most frequent, whereas for those with possible sleep bruxism, there was no specific period. The distribution of children between the groups was similar. The intragroup comparisons showed that the proportion of children who never changed day to night was significantly higher for the overall sample and for the groups without or with frequent possible sleep bruxism, whereas for the group with sometimes bruxism, to change never or seldom were similar. The proportion of children who change day to night often or always was significantly lower than those who change never or seldom, except for children with frequent bruxism.Table 3 Sample distribution in accordance with the predominant rhythm of the BRIAN-K scale (questions 18, 19, and 20) and the respective comparisons for the overall sample and between groups BRIAN-K Overall (N = 178) Without possible sleep bruxism (N = 101) Sometimes possible sleep bruxism (N = 41) Frequent possible sleep bruxism (N = 36) Between groups Test; P values Question 18 More willing/active [n (%)] Morning 33 (18.54) 16 (15.84) 8 (19.51) 9 (25.00) χ2 P = 0.812 Afternoon 51 (28.65) 31 (30.69) 13 (31.71) 7 (19.44) Night 37 (20.79) 22 (21.78) 8 (19.51) 7 (19.44) No specific shift 57 (32.02) 32 (31.68) 12 (29.27) 13 (36.11) χ2 (P values) P = 0.0336 P > 0.05 P > 0.05 P > 0.05 Question 19 More concentrated/ productive [n (%)] Morning 62 (34.83) 37 (36.63) 12 (29.27) 13 (36.11) Fisher’s exact test P = 0.685 Afternoon 65 (36.52) 40 (39.60) 13 (31.71) 12 (33.33) Night 22 (12.36) 11 (10.89) 7 (17.07) 4 (11.11) No specific shift 29 (16.29) 13 (12.87) 9 (21.95) 7 (19.44) χ2 (P values) P < 0.0001 P < 0.0001 P > 0.05 P > 0.05 Question 20 Change day to night [n (%)] Never 122 (68.54) 75 (74.26) 23 (56.10) 24 (66,67) Fisher’s exact test P = 0.130 Seldom 39 (21.91) 18 (17.82) 15 (36.59) 6 (16.67) Often 10 (5.62) 4 (3.96) 2 (4.88) 4 (11.11) Always 7 (3.93) 4 (3.96) 1 (2.44) 2 (5.56) χ2 (P values) P < 0.0001 P < 0.0001 P < 0.0001 P < 0.001 χ2 chi square; corresponding P values in each column mean intra-group comparison for proportions (χ2 adherence) The variables related to sleep, breathing, screen time, sugary food consumption, and teeth clenching are described in Table 4. It is possible to observe that no difference between groups occurred, except for clenching teeth since the group with sometimes possible sleep bruxism presented a higher proportion of children whose parents/guardian reported clenching teeth during wakefulness. On the other hand, the intragroup comparisons showed that for overall sample and children without possible sleep bruxism, the proportion of children with nasal breathing informed by parents/guardians was higher than oral breathing. The same happened for lights on in children’s bedroom and presence of noises near the children’s house. Although the respective absolute values for children with sometimes and frequent sleep bruxism were higher, they did not reach statistical significance. Intragroup comparisons showed that the number of children with or without reported clenching during wakefulness was similar only for those with sometimes sleep bruxism.Table 4 Descriptive data for variables related to sleep, breathing, screen time, sugary food consumption, and teeth clenching for the overall sample and groups and the respective comparisons Overall (N = 178) Without possible sleep bruxism (N = 101) Sometimes possible sleep bruxism (N = 41) Frequent possible sleep bruxism (N = 36) Between groups Test; P values Breathing [n (%)] Nasal 115 (64.61) 68 (67.33) 25 (60.98) 22 (61.11) χ2 P = 0.685 Oral 62 (34.83) 32 (31.68) 16 (39.02) 14 (38.89) χ2 P < 0.001 P < 0.001 P = 0.160 P = 0.182 Children’s bedroom lights [n (%)] Lights on 108 (60.67) 64 (63.37) 25 (60.98) 19 (52.78) χ2 P = 0.535 Lights off 70 (39.33) 37 (36.63) 16 (39.02) 17 (47.22) χ2 P = 0.004 P = 0.007 P = 0.160 P = 0.739 Noisy places near the children’s house [n (%)] Yes 64 (35.96) 34 (33.66) 15 (36.59) 15 (41.67) χ2 P = 0.668 No 114 (64.04) 67 (66.34) 26 (63.41) 21 (58.33) χ2 P < 0.001 P = 0.001 P = 0.086 P = 0.317 Screen time Working days (h) Mean (SD) 26.33 (15.76) 27.53 (15.79) 24.72 (13.54) 24.76 (18.02) ANOVA one way P = 0.511 Median (25–75%) 25 (15–36.83) 26.83 (15–40) 24 (16.83–35) 20.50 (11.37–35) Range 0–60 0–55 0–80 0–80 Screen time Weekend (h) Mean (SD) 7.54 (6.82) 8.11 (7.14) 8.04 (6.20) 5.38 (6.29) ANOVA one way P = 0.101 Median (25–75%) 6.75 (0–13) 7 (1–14) 8 (2–12) 2 (0–9.38) Range 0–24 0–24 0–19 0–21 Screen time: working days × weekend P < 0.001 P < 0.001 P < 0.001 P < 0.001 Mann–Whitney Hours of sleep Mean (SD) 9.66 (1.90) 9.74 (1.89) 9.42 (2.02) 9.69 (1.83) ANOVA one way P = 0.658 Median (25–75%) 9.50 (8.50–11) 9.50 (8.50–11) 9.50 (8.00–11) 10 (8.38–11.04) Range 3.50–16 3.5–15 5.5–16 5.5–13 Sugary food consumption (times a day) [n (%)] Never 5 (2.8) 2 (2.0) 0 3 (8.3) χ2 P = 0.567 1 17 (9.6) 9 (8.9) 6 (14.6) 2 (5.6) 2 35 (19.7) 20 (19.8) 6 (14.6) 9 (25.0) 3 34 (19.1) 21 (20.8) 8 (19.5) 5 (13.9) 4 39 (21.9) 21 (20.8) 8 (19.5) 10 (27.8) 5 33 (18.5) 20 (19.8) 7 (17.1) 6 (16.7) 6 7 (3.9) 4 (4.0) 3 (7.3) 0 7 6 (3.4) 2 (2.0) 3 (7.3) 1 (2.8) 8 1 (0.6) 1 (1.0) 0 0 9 1 (0.6) 1 (1.0) 0 0 χ2 P < 0.001 P < 0.001 P = 0.994 P = 0.598 Sugary food consumption before bedtime [n (%)] Yes 106 (59.6) 61 (60.4) 24 (58.5) 21 (58.3) χ2 P = 0.966 No 72 (40.4) 40 (39.6) 17 (41.5) 15 (41.7) χ2 P = 0.001 P = 0.037 P = 0.274 P = 0.317 Clenching teeth during wakefulness Yes 43 (24.2) 16 (15.8) 17 (41.5) * 10 (27.8) χ2 * P = 0.005 No 135 (75.8) 85 (84.2) 24 (58.5) 26 (72.2) χ2 P < 0.001 P < 0.001 P = 0.274 P = 0.008 χ2 chi square corresponding P values in each column mean intra-group comparison for proportions (χ2 adherence) *Means statistical significance between groups in the respective line Interesting to note, that the screen time was similar between groups both on working days and weekends, with significantly higher values for working days. The times a day that children consumed sugary foods were similar between the groups, but the number of children who consumed 3 to 5 times a day was significantly higher than at other times. In addition, the intra- and inter-group comparisons for hours of sleep and sugary food consumption before bedtime were not significantly different. Tables 5 and 6 include the results of multivariate ordinal logistic regressions, considering the order for possible sleep bruxism as the dependent variable. Categorical variables with P values less than 0.25 for inter- and intra-groups comparisons (Tables 1, 3, and 4) were included into the final models. The same criterion was applied for continuous variables according to univariate models (Online Resource 1). The second domain and question 18 of the BRIAN-K scale were forced into the final model. In addition, variables that did not meet the assumptions of ordinal logistic regression were not included in the models, since they presented multicollinearity into the models.Table 5 Multivariate ordinal logistic regression analysis for possible sleep bruxism, as the dependent variable and sociodemographic variables, as the independent variables Model coefficients—possible sleep bruxism (order: without, sometimes, frequent) 95% confidence interval Predictor Estimate SE Z P OR Lower Upper Sex (children): Masculine–feminine 0.429 0.307 1.399 0.162 1.54 0.84 2.81 Weight status (children) Underweight–normal 0.539 0.640 0.842 0.400 1.71 0.47 5.99 Overweight–normal 0.351 0.380 0.921 0.357 1.42 0.67 2.99 Obesity–normal 0.289 0.391 0.739 0.460 1.34 0.62 2.88 Mother educational status 1 degree–2 degree − 0.088 0.389 − 0.225 0.822 0.92 0.42 1.95 Graduated–2 degree 0.029 0.408 0.072 0.943 1.03 0.46 2.28 Mother marital status: Single–married 0.608 0.427 1.422 0.155 1.84 0.79 4.27 Divorced–married 0.735 0.477 1.543 0.123 2.09 0.81 5.31 Others–married 0.459 0.440 1.042 0.297 1.58 0.66 3.75 Family income (wage per month): Less than 1–between 1 and 2 0.045 0.548 0.082 0.935 1.05 0.34 3.01 Between 3 and 4–between 1 and 2 0.513 0.396 1.295 0.195 1.67 0.77 3.66 More than 4–between 1 and 2 0.764 0.462 1.654 0.098 2.15 0.87 5.36 Nagelkerke’s (R2N) = 0.040, VIF = 1.03–1.08, Tolerance = 0.923–0.967, Proportional odds P > 0.05 Variables not included–did not meet ordinal logistic regression assumptions Table 6 Multivariate ordinal logistic regression analysis for possible sleep bruxism as the dependent variable, and variables related to sleep, screen time, sugary food consumption, and clenching teeth as the independent variables Model coefficients—possible sleep bruxism (order: without, sometimes, frequent) 95% confidence interval Predictor Estimate SE Z P OR Lower Upper First domain–sleep 0.184 0.062 2.969 0.003 1.20 1.07 1.36 Second domain–routine activities 0.024 0.060 0.404 0.686 1.03 0.91 1.15 Third domain–social rhythm − 0.035 0.081 − 0.429 0.668 0.97 0.82 1.13 Fourth domain–eating pattern − 0.005 0.067 − 0.075 0.940 1.00 0.87 1.13 Q 18: More willing/active Afternoon–morning − 0.749 0.491 − 1.527 0.127 0.47 0.18 1.24 Night–morning − 0.979 0.571 − 1.716 0.086 0.38 0.12 1.14 No specific shift–morning − 0.413 0.458 − 0.903 0.366 0.66 0.27 1.63 Q 19: More concentrated/productive Afternoon–morning − 0.375 0.422 − 0.888 0.375 0.69 0.30 1.57 Night–morning − 0.759 0.609 − 1.247 0.212 0.47 0.14 1.52 No specific shift–morning 0.375 0.470 0.798 0.425 1.46 0.58 3.67 Q 20: Change day to night Seldom–never 0.209 0.412 0.506 0.613 1.23 0.55 2.77 Often–never 0.915 0.752 1.217 0.224 2.50 0.56 11.06 Always–never 0.222 0.846 0.263 0.793 1.25 0.21 6.37 Breathing: Mouth–nose 0.122 0.332 0.366 0.714 1.13 0.59 2.16 Children’s bedroom lights: No–yes 0.340 0.343 0.990 0.322 1.41 0.72 2.76 Noisy places near the children’s house No–yes − 0.084 0.354 − 0.237 0.813 0.92 0.46 1.85 Screen time–working days (hs) − 0.007 0.011 − 0.637 0.524 0.99 0.97 1.01 Screen time–weekend (hs) − 0.036 0.026 − 1.372 0.170 0.97 0.92 1.02 Sugary food consumption before bedtime No–yes − 0135 0.342 − 0.396 0.692 0.87 0.44 1.7 Clenching teeth during wakefulness Yes–no 0.710 0.360 1.975 0.048 2.04 1.00 4.13 Nagelkerke’s (R2N) = 0.114, VIF 1.04–1.37, Tolerance 0.73–0.96, Proportional odds P > 0.05, SE standard error, OR odds ratio Significant P-values are in bold fonts. Sociodemographic variables were not associated with possible sleep bruxism, considering the P values greater than 0.05 and confidence intervals containing the value 1 in the model (Table 5). The second model of multivariate ordinal analysis (Table 6) showed that the first domain of the BRIAN-K scale, which is related to sleep difficulties, was significantly associated with possible sleep bruxism. In this context, as the values of the first domain increase, i.e., more sleep difficulties, the chance of a child having possible sleep bruxism more frequently increases (OR = 1.20). Furthermore, the chance of children to increase the frequency of possible sleep bruxism if they clench their teeth during wakefulness was about twice as high (OR = 2.04). Unexpectedly, other variables related to sleep and sugary food consumption showed no association with possible sleep bruxism. Discussion The present study aimed to verify whether children with sleep bruxism present changes in their biological rhythm, regarding sleep, daily routine activities, social behavior and feeding and the possible associated factors, such as sociodemographic variables, weight status, sleep characteristics, and clenching teeth during wakefulness reported by parents/guardians. The possible association between sleep bruxism with the variables responsible for the interruption of the biological rhythm in children could help to clarify the multifactorial picture of bruxism, in addition to being a tool for possible diagnoses [22]. It was observed that the number of boys with possible sleep bruxism was the same as that of girls, corroborating previous studies [22], and disagreeing with Restrepo et al. [11]. Nevertheless, sleep bruxism prevalence in children has presented a greater variability, with a commonly described decrease with age and no gender differences, due to different methodologies concerning the age groups studied, as well as the different frequencies of self-reported sleep bruxism [6]. Geographical variation among studies exists in the epidemiology of parental-reported sleep bruxism in children, and cultural rules and standards could explain the variability in prevalence [27]. Moreover, in a recent systematic review [28], it was also considered that the prevalence does not vary between sexes, presumably due to individual factors rather than regional or collective ones. The frequency of children with possible bruxism was almost half of the total sample, (43.26%), which can be considered high compared with other studies, as stated in the systematic review by Soares et al. [29]. This high frequency could be attributed to routine change due to the confinement determined by the COVID 19 pandemic, influencing sleep, schedules and feeding. According to Sohrab [30], the increase in cases of bruxism may be related to reduced contact with other children, increased pressure arising from the new context of online classes and the absence of team sports in this period of social confinement, which have contributed to the greater screen time and frequency during this pandemic period. In addition, uncertainty regarding factors such as the origin of SARS-COV-2, the government’s ability to prevent the spread of the disease, and the severity of the risks cause considerable family stress, with emotional and financial consequences that could influenced children behavior [31, 32]. However, we cannot yet confirm such an association, as no study with a longitudinal design has addressed aspects related to sleep in children, or the association between the period of social isolation and clinical factors related to dentistry [21]. Regarding the anthropometric assessment (weight and height), half of the sample was overweight or obese. This finding is in line with the high prevalence of overweight/obesity children in Brazil, agreeing with a projection made by the Ministry of Health in 2018 indicating that in the 2022, the number of obese children in Brazil would be around 46.5% (https://www.gov.br/saude). The COVID-19 pandemic, the period in which the present data were collected, can also aggravate the situation, and had an important impact on the diet of children and adolescents, in addition to the increase in sedentary lifestyle [33]. Considering the sleep-obesity relationship and the biopsychosocial characteristics involved [34] plus the sleep bruxism, which is an activity of the masticatory muscles that obviously occurs during sleep, the weight status could be an important factor in this context. However, no significant association was found between the children’s BMI and weight status with possible sleep bruxism, agreeing with Juliatte et al. [35] who observed no association in adults assisted by the public health system. The lack of association in the present study could be attributed to the fact that despite the high frequency of overweight and obesity in the sample, the children did not present comorbidities. In fact, sleep bruxism may be indirectly associated with obesity, as found by Holanda et al. [36] who observed in adults a significant relationship between sleep bruxism, BMI, and alcohol consumption. Moreover, obesity can increase the risk of snoring and obstructive sleep apnea in children [37, 38]. In this context, snoring has been linked to sleep bruxism [39], and an association between obstructive sleep apnea (OSA) and sleep bruxism may be possible in children, although supportive evidence is still required [40]. Thus, it is important that snoring and OSA are taken into account in studies of sleep bruxism, with accurate diagnostic methods, to increase the evidence [40]. Although the relationship between sleep bruxism and the presence of comorbidities has been emerging [41], it must be remembered that sleep bruxism is considered a sleep behavior rather than sleep disorder [1, 2]. The results showed that sociodemographic variables were not different among groups, or associated with possible sleep bruxism, probably due the homogeneity of the sample in those aspects, agreeing with Sampaio et al. [42]. The evaluation of different social strata could point out the influence of sociodemographic factors on sleep bruxism, as done by Manfredini et al. [43]. On the BRIAN-K total scale, children with sleep bruxism had higher scores on biological rhythm variables in general, meaning that they were having more difficulties in maintaining the biological rhythm than children without sleep bruxism. For identify the factors that were determining high scores for the total BRIAN-K scale, the respective domains were compared among groups, and only the first domain, sleep, showed higher significant values for children with possible sleep bruxism, as found previously [22]. Difficulty in maintaining sleep rhythm may be related, for example, to trouble waking up, feeling unrefreshed with the number of hours of sleep and having no regular bedtime, as assessed in the first domain of the BRIAN-K scale. In fact, it has been observed that sleep bruxism can determine the cited sleep problems [44] and can be associated with reduced sleep time [9]. These changes may be associated with the fact that sleep bruxism occurs in conjunction with sleep disturbances, body movements, breathing problems, increased muscle activity and heart rate disturbances, which can directly affect a child’s ability to have a good night sleep [45]. It must be considered that sleep disturbances can affect physical, behavioral, and cognitive functioning, and children are vulnerable to the effects of an inadequate amount or poor quality of sleep [46]. Although, in general, children with sleep bruxism had high scores in the other domains (activity, food and social), there were no significant differences between groups. These findings disagree with Bach et al. [22] who state that children with sleep bruxism had greater difficulty in maintaining rhythm in all domains of BRIAN-K scale. Most likely, the divergent results could be due to the pandemic period of COVID-19, since the confinement could have influenced or restricted the daily activities, socialization, and feeding, which are accessed on the BRIAN-K scale by second to fourth domains. Consequently, the predominant rhythms were similar between children with and without possible sleep bruxism. Most children were more active in the afternoon or did not have a specific shift, corroborating the findings of the first domain, related to sleep maintenance and its influence on feeling refreshed in the morning. Furthermore, most were more concentrated/productive during the day. Regarding the change day to night, most children never changed, but a higher proportion of those with sometime possible sleep bruxism who changed seldom was observed, perhaps due to poor sleep, which influenced factors must be determined [47]. The sample distribution related to sleep, such as lights on or off, sleep hours, and noises near the house did not differ between groups. These were unexpected results, first because noises, light stimulus, and sleep time less than 8 h have been considered influencing factors in children with sleep bruxism [9]; second to the fact that BRIAN-K scores for sleep domain was higher for groups with possible sleep bruxism. Nevertheless, this is still a controversial issue since environmental factors did not influence triggering sleep bruxism [48], as found in the present study. Perhaps the different designs between studies could explain the divergent results. Additionally, screen use, sugar consumption, and breathing were not different between groups. Interestingly, average screen time on weekdays was significantly higher than on weekends, which may be due to the period of the COVID-19 pandemic, when children had a break from routine and the inclusion of online classes. Additionally, screen use, sugary consumption, and breathing were not different between groups. Interestingly, the mean screen time during workdays was significantly higher that on weekends, which could be due to the online classrooms when the data were collected. High sugar consumption has been identified as an influencing factor on sleep bruxism [11], but in the present study, the general need to use technology to meet the needs during the pandemic, could justify the findings. It has also been stated that sugar consumption can be associated with sleeping and behavior disorders, which in turn can be associated with possible sleep bruxism [11] altering the circadian rhythm [49]. Dopamine is involved in the etiology of sleep bruxism and sugar and screen time can affect its neurotransmission [50]. Nevertheless, the frequency of sugar consumption and consumption before bedtime were similar, diverging from Restrepo et al. [11] who observed a positive association between possible sleep bruxism and increase-to-increase sugar-consumption. In the study by Restrepo et al. [11] the Health Behaviour in School-Aged Children Food-Frequency Questionnaire was applied, which could obtain more details about the foods consumed, whereas in the present study only the frequency was considered. In the bivariate analysis, reported clenching teeth during wakefulness by children with sometimes possible sleep bruxism was proportionally higher than the other children. This is an interesting result, as clenching teeth during wakefulness is a sign of awake bruxism, but this behavior requires a more detailed and long-term assessment for a precise diagnosis. This is in line with the present result related to the association of clenching during wakefulness with possible sleeping bruxism, since the odds ratio showed that children who presented clenching during wakefulness are 2.04 times more likely to have sleep bruxism. This result agrees with Duarte et al. [51], who found that schoolchildren with awake bruxism presented the greater chance to have possible sleep bruxism about three times. Clenching teeth is a sign of awake bruxism, but it was not considered awake bruxism per se in the present methodology, since the respective diagnosis requires a more precise assessment, as commented above, such as reports of clenching for 1–2 weeks and the frequency of the behavior [1, 3, 52]. In a systematic review, Castroflorio et al. [53] sought to identify the risk factors associated with sleep bruxism in children, concluding that sleep disorders showed stronger association with sleep bruxism, that is children with sleep disturbances were more likely to have sleep bruxism. This is in line with the present result related to the association of the first domain of the BRIAN-K scale with possible sleeping bruxism, meaning that how much difficulty is required to maintain sleep rhythm, increases the probability of triggering possible sleep bruxism with more frequency. Previous studies report that possible sleep bruxism is more common in children with sleep deprivation and microarousals [54, 55]. This can be explained by the fact that the absence of restful sleep can predispose children to increased anxiety and stress [54], consequently increasing the likelihood of sleep bruxism. In this context, it must be remembered that the period of pandemic could be contributed to sleep disturbances. The present study had limitations related to the lack of a definite sleep bruxism diagnosis by polysomnography. However, the assessment of sleep bruxism using reports by parents/guardians, including frequency, was in accordance with the latest International Consensus on Bruxism [1], thus ensuring the reasonableness of the data obtained. Although the present results on overweight and obesity were not linked to sleep bruxism, the lack of questions related to snoring and OSA can be considered as limitation and should be addressed in further studies. Moreover, the period in which the research was carried out (COVID-19 pandemic) resulted in some loss of data and participants, but the interviews with parents/guardians were carried out carefully on a digital platform, getting confident information. Another limitation was related to the fact that this is a cross-sectional study, consequently, it was not possible to establish causality. The period of the COVID-19 pandemic may have had influence on the variables studied. Therefore, post pandemic longitudinal studies are required to establish the cause-effect of factors related to sleep bruxism in children, considering the definitive diagnosis. In conclusion, children with possible sleep bruxism had greater difficulty in maintaining biological rhythm, specifically in maintaining sleep, than children without sleep bruxism. The increase in the scores of the first domain of the Brian-K scale, related to sleep characteristics, plus the report of parents/guardians that their children clenched their teeth during wakefulness increased the chances of them having a possible sleep bruxism more frequently. Supplementary Information Below is the link to the electronic supplementary material.Supplementary file1 (DOCX 15 KB) Acknowledgements The authors are grateful to Coordenação de Aperfeiçoamento de Pessoal de Nível Superior–Brasil (CAPES) and Conselho Nacional de Desenvolvimento Científico e Tecnológico, (CNPq, Brazil) for the scholarships for the first author. The authors thank the directors and teachers from the Public Schools of Piracicaba, SP, Brazil, for collaboration and participating in the study and all parents/guardians for their adherence to the online interviews. Authors’ contributions C.R.V. Marceliano contributed to the study protocol, ethics application, performed the recruitment of the participants, collected and analyzed the data, contributed to the interpretation of the reported results and the production of figures, and wrote the first draft of the manuscript. This author gave final approval for submission. M.B.D. Gavião developed the study concept, wrote the study protocol and ethics application, analyzed the data, performed statistical analysis, contributed to the interpretation of the reported results and the production of figures, and wrote the first draft of the manuscript. This author critically reviewed the manuscript, commented on the text and gave final approval for submission. All authors have read and approved the manuscript. Funding This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES)—Finance Code 001 and Conselho Nacional de Desenvolvimento Científico e Tecnológico, Process 134016/2019–0 (CNPq, Brazil). Data Availability The data that support the findings of this study are available from the corresponding author upon reasonable request. Declarations Ethics approval Approval was obtained from the ethics committee of the Piracicaba Dental School, University of Campinas (FOP-UNICAMP) and approved under CAAE opinion number 3618619.6.0000.5418. The procedures used in this study adhere to the tenets of the Declaration of Helsinki. Consent to participate All participants signed the Free and Informed Consent Term. Competing interests The authors declare that they have no competing interests. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Lobbezoo F Ahlberg J Raphael KG Wetselaar P Glaros AG Kato T Santiago V International consensus on the assessment of bruxism: report of a work in progress J Oral Rehabil 2018 45 837 844 10.1111/joor.12663 29926505 2. Lobbezoo F Ahlberg J Glaros AG Kato T Koyano K Lavigne GJ de Leeuw R Manfredini D Svensson P Winocur E Bruxism defined and graded: an international consensus J Oral Rehabil 2013 40 2 4 10.1111/joor.12011 23121262 3. Bracci A Lobbezoo F Häggman-Henrikson B Colonna A Nykänen L Pollis M Ahlberg J Manfredini D International network for orofacial pain and related disorders methodology INfORM Current Knowledge and Future Perspectives on Awake Bruxism Assessment Expert Consensus Recommendations J Clin Med 2022 11 5083 10.3390/jcm11175083 36079013 4. Wieckiewicz M Bogunia-Kubik K Mazur G Danel D Smardz J Wojakowska A Genetic basis of sleep bruxism and sleep apnea-response to a medical puzzle Sci Rep 2020 10 7497 10.1038/s41598-020-64615-y 32367059 5. Smardz J Martynowicz H Wojakowska A Wezgowiec J Danel D Mazur G Wieckiewicz M Lower serotonin levels in severe sleep bruxism and its association with sleep, heart rate, and body mass index J Oral Rehabil 2022 49 422 429 10.1111/joor.13295 34907576 6. Manfredini D Restrepo C Diaz-Serrano K Winocur E Lobbezoo F Prevalence of sleep bruxism in children: a systematic review of the literature J Oral Rehabil 2013 40 6316 6342 10.1111/joor.12069 7. Wetselaar P Vermaire EJH Lobbezoo F Schuller AA The prevalence of awake bruxism and sleep bruxism in the Dutch adult population J Oral Rehabil 2019 46 617 623 10.1111/joor.12787 30830687 8. Kuhn M Türp JC Risk factors for bruxism Swiss Dent J 2018 128 118 124 29533049 9. Serra-Negra JM Lobbezoo F Martins CC Stlinni E Manfredini D Prevalence of sleep bruxism and awake bruxism in different chronotype profiles: hypothesis of an association Medical Hypotheses 2017 101 55 58 10.1016/j.mehy.2017.01.024 28351492 10. Guo H Wang T Niu X Wang H Yang W Qiu J Yang L The risk factors related to bruxism in children: a systematic review and meta-analysis Arch Oral Biol 2018 86 18 34 10.1016/j.archoralbio.2017.11.004 29149621 11. Restrepo C Santamaría A Manrique R Sleep bruxism in children: relationship with screen-time and sugar consumption Sleep Med X 2021 3 100035 10.1016/j.sleepx.2021.100035 34169271 12. Ramos-Lopez O Panduro A Rivera-Iñiguez I Roman S Dopamine D2 receptor polymorphism (C957T) is associated with sugar consumption and triglyceride levels in West Mexicans Physiol Behav 2018 1 194 532 537 10.1016/j.physbeh.2018.07.004 13. Weinstein A Livny A Weizman A New developments in brain research of internet and gaming disorder Neurosci Biobehav Rev 2017 75 314 330 10.1016/j.neubiorev.2017.01.040 28193454 14. Blume C Schmidt MH Cajochen C Effects of the COVID-19 lockdown on human sleep and rest-activity rhythms Curr Biol 2020 20 30 R795 R797 10.1016/j.cub.2020.06.021 15. Korman M Tkachev V Reis C Komada Y Kitamura S Gubin D Kumar V Roenneberg T COVID-19-mandated social restrictions unveil the impact of social time pressure on sleep and body clock Sci Rep 2020 10 1 22225 10.1038/s41598-020-79299-7 33335241 16. Wilder-Smith A Freedman DO Isolation, quarantine, social distancing and community containment: pivotal role for old-style public health measures in the novel coronavirus (2019-nCoV) outbreak J Travel Med 2020 27 2 taaa020 10.1093/jtm/taaa020 32052841 17. Brooks SK Webster RK Smith LE Woodland L Wessely S Greenberg N Rubin GJ The psychological impact of quarantine and how to reduce it: rapid review of the evidence Lancet 2020 395 10227 912 920 10.1016/S0140-6736(20)30460-8 32112714 18. Rajkumar RP COVID-19 and mental health: A review of the existing literature Asian J Psychiatr 2020 52 102066 10.1016/j.ajp.2020.102066 32302935 19. Emodi-Perlman A Eli I Smardz J Uziel N Wieckiewicz G Gilon E Grychowska N Wieckiewicz M Temporomandibular disorders and bruxism outbreak as a possible factor of orofacial pain worsening during the COVID-19 pandemic-concomitant research in two countries J Clin Med 2020 9 10 3250 10.3390/jcm9103250 33053640 20. Winocur-Arias O Winocur E Shalev-Antsel T Reiter S Levartovsky S Emodi-Perlman A Friedman-Rubin P Painful temporomandibular disorders, bruxism and oral parafunctions before and during the COVID-19 pandemic era: a sex comparison among dental patients J Clin Med 2022 11 3 589 10.3390/jcm11030589 35160041 21. Lima LCM Leal TR Araújo LJS Sousa MLC Silva SED Serra-Negra JMC Impact of the COVID-19 pandemic on sleep quality and sleep bruxism in children eight to ten years of age Braz Oral Res 2022 36 e046 10.1590/1807-3107bor-2022.vol36.0046 35442376 22. Bach SL Moreira FP Goettems ML Brancher LC Oses JP da Silva RA Salivary cortisol levels and biological rhythm in schoolchildren with sleep bruxism Sleep Med 2019 54 48 52 10.1016/j.sleep.2018.09.031 30529777 23. Schimitt RL Zanetti T Mayer M Koplin C Guarienti F Hidalgo MP Psychometric properties of Social Rhythm Metric in regular shift employees Braz J Psychiatry 2010 32 47 55 10.1590/s1516-44462010000100010 20339734 24. Mondin TC Cardoso TA Souza LDM Jansen K Da Silva Magalhães PV Kapczinski F Mood disorders and biological rhythms in young adults: a large population-based study J Psychiatr 2017 84 98 104 10.1016/j.jpsychires.2016.09.030 25. Barnard AR Nolan PM When clocks go bad: neurobehavioural consequences of disrupted circadian timing PLoS Genet 2008 4 5 e1000040 10.1371/journal.pgen.1000040 18516223 26. Berny T Jansen K Cardoso TA Mondin TC Silva RAD Souza LDM Construction of a biological rhythm assessment scale for children Trends Psychiatry Psychother 2018 40 53 60 10.1590/2237-6089-2017-0081 29668820 27. Van Selms MKA Marpaung C Pogosian A Lobbezoo F Geographical variation of parental-reported sleep bruxism among children: comparison between the Netherlands, Armenia and Indonesia Int Dent 2019 J69 237 243 10.1111/idj.12450 28. Ferrari-Piloni C Barros LAN Evangelista K Serra-Negra JM Silva MAG Valladares-Neto J Prevalence of bruxism in Brazilian children: a systematic review and meta-analysis Pediatr Dent 2022 15 44 8 20 29. Soares JP Giacomin A Cardoso M Serra-Negra JM Bolan M Association of gender, oral habits, and poor sleep quality with possible sleep bruxism in schoolchildren Braz Oral Res 2020 34 e019 10.1590/1807-3107bor-2020.vol34.0019 32187305 30. Sohrab C Alsafi Z O’Neill N Khan M Kerwan A Al-Jabir A World Health Organization declares global emergency: a review of the 2019 novel coronavirus (COVID-19) Int J Surg 2020 76 71 76 10.1016/j.ijsu.2020.02.034 32112977 31. Ferreira VR Jardim TV Póvoa TIR Viana RB Sousa ALL Jardim PCV Physical inactivity during leisure and school time is associated with the presence of common mental disorders in adolescence Rev Saude Publica 2020 54 128 10.11606/s1518-8787.2020054001888 33295594 32. World Health Organization (2020) Coronavirus disease 2019 (COVID-19): situation report, 51. World Health Organization. https://apps.who.int/iris/handle/10665/331475 33. Zabetakis I Lordan R Norton C Tsoupras A COVID-19: The Inflammation Link and the Role of Nutrition in Potential Mitigation Nutrients 2020 12 5 146 10.3390/nu12051466 31947975 34. Barragán R Zuraikat FM Tam V Scaccia S Cochran J Li S Cheng B St-Onge M-P Actigraphy-derived sleep is associated with eating behavior characteristics Nutrients 2021 13 3 852 10.3390/nu13030852 33807690 35. Juliatte TPR Costa PD Canaan JDR Fonseca DC Serra-Negra JM Andrade EF Castelo PM Pereira LJ Circadian preference and its relationship with possible sleep and awake bruxism in adults assisted by the public health system Chronobiol Int 2022 39 68 76 10.1080/07420528.2021.1973487 34517733 36. de Holanda TA Castagno CD Barbon FJ Costa YM Goettems ML Boscato N Sleep architecture and factors associated with sleep bruxism diagnosis scored by polysomnography recordings: A case-control study Arch Oral Biol 2020 112 104685 10.1016/j.archoralbio.2020.104685 32097767 37. Jehan S Zizi F Pandi-Perumal SR Wall S Auguste E Myers AK Obstructive sleep apnea and obesity: implications for public health Sleep Med Disord 2017 1 4 00019 29517065 38. Tan YH How CH Chan YH Teoh OH Approach to the snoring child Singapore Med J. 2020 61 170 175 10.11622/smedj.2020054 32500157 39. Michalek-Zrabkowska M Wieckiewicz M Macek P Gac P Smardz J Wojakowska A Poreba R Mazur G Martynowicz H The relationship between simple snoring and sleep bruxism: a polysomnographic study Int J Environ Res Public Health 2020 17 8960 10.3390/ijerph17238960 33276496 40. Pauletto P Polmann H Conti Réus J Massignan C de Souza BDM Gozal D Sleep bruxism and obstructive sleep apnea: association, causality or spurious finding A scoping review Sleep 2022 45 zsac073 10.1093/sleep/zsac073 35443064 41. Segù M Pollis M Santagostini A Meola F Manfredini D Correlation between Parental-Reported Tooth Grinding and Sleep Disorders: Investigation in a Cohort of 741 Consecutive Children Pain Res Manag 2020 2020 3408928 10.1155/2020/3408928 32802220 42. Sampaio NM Oliveira MC Andrade AC Santos LB Sampaio M Ortega A Relationship between stress and sleep bruxism in children and their mothers: a case control study Sleep Sci 2018 11 239 244 10.5935/1984-0063.20180038 30746041 43. Manfredini D Lobbezoo F Giancristofaro RA Restrepo C Association between proxy-reported sleep bruxism and quality of life aspects in Colombian children of different social layers Clin Oral Investig 2017 21 1351 1358 10.1007/s00784-016-1901-5 27417100 44. Carra MC Rompré PH Kato T Parrino L Terzano MG Lavigne GJ Macaluso GM Sleep bruxism and sleep arousal: an experimental challenge to assess the role of cyclic alternating pattern J Oral Rehabil 2011 38 635 642 10.1111/j.1365-2842.2011.02203.x 21299589 45. Oliveira L Gomes C Bacelar Nicolau L Ferreira L Ferreira R Environment in pediatric wards: light, sound, and temperature Sleep Med 2015 16 1041 1048 10.1016/j.sleep.2015.03.015 26298777 46. Beebe DW Cognitive, behavioral, and functional consequences of inadequate sleep-in children and adolescents Pediatr Clin North Am 2011 58 649 665 10.1016/j.pcl.2011.03.002 21600347 47. Lages NC Debbeler LJ Blumenschein M Kollmann J Szymczak H Keim DA Dynamic risk perceptions in times of avian and seasonal influenza epidemics: a repeated cross-sectional design Risk Ana 2021 41 11 2016 2030 10.1111/risa.13706 48. Serra-Negra JM Ribeiro MB Prado IM Paiva SM Pordeus IA Association between possible sleep bruxism and sleep characteristics in children Cranio 2017 35 315 320 10.1080/08869634.2016.1239894 27691903 49. Becker DB Schwartz AI Let There Be Light J Mass Dent Soc 2015 64 7 26727809 50. Scariot R Brunet L Olsson B Palinkas M Regalo SCH Rebellato NLB Single nucleotide polymorphisms in dopamine receptor D2 are associated with bruxism and its circadian phenotypes in children Cranio 2022 40 152 159 10.1080/08869634.2019.1705629 31868570 51. Duarte J Souza JF Cavalcante-Leão B Todero SRB Ferreira FM Fraiz FC Association of possible sleep bruxism with daytime oral habits and sleep behavior in schoolchildren Cranio 2021 39 372 378 10.1080/08869634.2019.1661113 31483213 52. Dias R Vaz R Rodrigues MJ Serra-Negra JM Bracci A Manfredini D Utility of Smartphone-based real-time report (Ecological Momentary Assessment) in the assessment and monitoring of awake bruxism: a multiple-week interval study in a Portuguese population of university students J Oral Rehabil 2021 48 1307 1313 10.1111/joor.13259 34536309 53. Castroflorio T Bargellini A Rossini G Cugliari G Rainoldi A Deregibus A Risk factors related to sleep bruxism in children: a systematic literature review Arch Oral Biol 2015 60 11 1618 1624 10.1016/j.archoralbio.2015.08.014 26351743 54. Bortoletto CC Salgueiro MDCC Valio R Fragoso YD Motta PB Motta LJ The relationship between bruxism, sleep quality, and headaches in schoolchildren J Phys Ther Sci 2017 29 1889 1892 10.1589/jpts.29.1889 29200617 55. Guo L Luo M Wang WX Huang GL Xu Y Gao X Association between problematic Internet use, sleep disturbance, and suicidal behavior in Chinese adolescents J Behav Addict 2018 1 7 965 975 10.1556/2006.7.2018.115
PMC009xxxxxx/PMC9936128.txt	==== Front J. Comput. Educ. Journal of Computers in Education 2197-9987 2197-9995 Springer Berlin Heidelberg Berlin/Heidelberg 259 10.1007/s40692-023-00259-x Article Digital storytelling to facilitate academic public speaking skills: case study in culturally diverse multilingual classroom Roza Zhussupova 1Zhussupova Roza is an Ass.Professor in the Department of Theory and Practice of Foreign Languages, Philology at the faculty of L. N. Gumilyov Eurasian National University, Nur-Sultan city, Kazakhstan. Her research interest includes English theory and EFLT. http://orcid.org/0000-0001-5571-1158 Rustam Shadiev [email protected] 2Shadiev Rustam is professor at the College of Education, Zhejiang University, China. He received the title of distinguished professor of Jiangsu province, China in 2019. He is a Fellow of the British Computer Society and a Senior Member of the Institute of Electrical and Electronics Engineer. Rustam Shadiev was selected as the Most Cited Chinese Researchers in the field of Education by the Elsevier, Scopus and Shanghai rating in 2020 and 2021. His research interest includes advanced learning technologies to support language learning and cross-cultural education. 1 grid.55380.3b 0000 0004 0398 5415 L.N. Gumilyov Eurasian National University, Astana City, Kazakhstan 2 grid.13402.34 0000 0004 1759 700X Zhejiang University, Hangzhou City, China 17 2 2023 128 30 5 2022 28 12 2022 13 1 2023 © Beijing Normal University 2023, corrected publication 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. A small scale study is reported in the article in an effort to determine the impact of enhancing cultural diversity in teaching academic public speaking skills as a result of Digital Storytelling (DS) implementation in multilingual classrooms of 2nd year TEFL pre-service students who took training over 7 weeks to become teachers of English as a foreign language. DS represents a powerful way of making/telling short stories using animation, website, audio video, and graphics. We explored DS in the English Language Classroom for TEFL pre-service students for developing public speaking skills because DS improves vocabulary enrichment and oral skills. Teachers also access students’ English language fluency, coherence, and cohesion to identify areas of academic public speaking skills improvement for their multilingual students. The experimental teaching had several stages, namely the introductory phase when students were supposed to decide on the topic of their stories and make initial drafts. The second phase was dedicated to the verification of the final draft by a tutor. During the last phase of the project, students performed their own DS with public presentations. The study used mixed research methods, i.e. both qualitative (focus group) and quantitative (questionnaires and rubrics) methods. Students used devices with digital capabilities to record narrations so their created DS included their personally produced public speech. Our results demonstrated that DS provided an opportunity to make students’ speech more coherent and cohesive because points of descriptors such as fluency, coherence, and cohesion of academic public speaking performances significantly improved by 15%. Moreover, this technique depicted a positive outcome because of its constant reiteration of academic vocabulary and grammar in multilingual groups, and cultural diversity in different nations. Keywords Foreign language learning and teaching Digital storytelling Linguistic and cultural diversity Academic public speaking skills Pre-service teachers ==== Body pmcIntroduction Cultural diversity Nowadays, in the 21st century, we live in a world where communication has vast importance in every sphere of our lives. We use language as a means of communication. Language exists to help with interaction, and it is a crucial part of national history and culture. There is a big role in intercultural communication notions such as multilingualism and cultural diversity. Theoretically, the term cultural diversity possesses various meanings. Sociologically, it means the existence of numerous ethnic groups with different cultures coming jointly in society. Ideologically, it also refers to social analyses that affirm cultural origins at differing levels by numerous ethnic dominations (Aronin & Singleton, 2010). The correlated specific ideas are multiculturalism, ethnic diversity, and cultural pluralism (Krashen, 2010). Hence an increasingly racially and ethnically varied society is described in many ways by the phrase cultural diversity. It relates to an individual’s development of their cultural identity and interactions with others. The phrase has meaning in how cultural groups organize themselves nationally and how the governments utilize the legislation to promote or restrict variety (Capra, 2005; Cenoz, 2009; Edwards, 1994). The question of globalization and how changes in economic, political, and social activities will affect the diversity of the world are intertwined with cultural diversity on a global scale (Dewaele, 2010). To advance educational quality, it is necessary to introduce innovative progressive pedagogical digital capabilities into teaching and learning. Implementing new technologies in teaching English is due to the realities of today. The modern lesson cannot be imagined without computer-assisted tools. With modern educational gadgets, study innovation is now largely advanced by many steps and has made huge steps towards quality improvement. With the development of the Internet, there are new opportunities for teaching foreign languages (Shayakhmetova et al., 2020). The effectiveness of operating with innovative tools depends mainly on teachers’ competencies (Duduney et al., 2014). However, implementing technologies in the learning process should be carried out carefully and with all precautions (Shadiev & Liu, 2023). As it was noted digital technologies represent positive feedback in teaching pre-service teachers (Gavaldon & McGarr, 2019). To plan a good lesson, a language teacher follows certain criteria because multilingualism is not only a high goal set by Kassym-Jomart Tokayev, the President of Kazakhstan, but the concept of “multilingualism” is also filled with some aspects of the professional plan. Mostly it means the implementation of integrated subject learning in interdisciplinary connections in the classroom, broadening students’ horizons and cultural cross-fertilization through the acquisition of languages, and development of intercultural awareness, tolerance, and internationalism (Kunanbayeva, 2016). Teaching factual usage of the target language in spoken and written forms of communication promotes students to express their identities and intelligence in the language in compelling ways, consolidating their internalization of the code (Cummins, 2001). It has been proven that storytelling is used as an approach for delivering cultural issues from generation to generation. Narrating is a clear way of communication between nations and the benefits and drawbacks of short stories during learning and teaching the target language are well described in methodological works (Author, 2016). DS Nowadays DS proposes an innovative and digital mode of retelling stories with the help of computer-assisted tools and techniques, and it routes modern story narration by mixing numerous media such as websites, audio, video, animation, and graphics to design colorfully creative live sessions (Brenner, 2014; Hwang et al., 2016). DS is considered an amazing educational approach that aids learners in the comprehension of topics and specific knowledge (Shadiev et al., 2017). What is more, DS enables students to use their visual, auditory, and kinesthetic skills. DS is a great tool that enhances creativity and thinking skills in the students when they brainstorm to make a story. It also helps students to learn how to collaborate and work in a team. As Patricia Search identifies DS as a technique that contributes to combining interactive technology with the traditional art of storytelling to produce national narratives that immerse the audience in new cultural experiences (Search, 2015). DS enables ordinary people to contribute snippets of their tales in a condensed form of digital media production. The multimedia used can be the digital equivalent of film techniques (full-motion video with sound), still images, audio recordings, or any other non-physical media (material that only exists as electronic files as opposed to actual paintings or photographs on paper, sounds stored on tape or disc, movies stored on film). There are numerous meanings of DS but generally speaking they all center on the idea of fusing the craft of storytelling with a range of digital multimedia, such as images, photos, graphics, audio, and video. To provide a piece of information on a particular topic, almost all digital stories include graphics, recorded text with audio and video, and musically followed. As a co-founder of the Center for DS (CDS), a non-profit, community arts organization in Berkeley, California, Lambert helped DS get off the ground as a relatively new concept. In addition to providing training and assistance since the early 1990s, Lambert and the CDS have developed and disseminated the Seven Components of DS. While DS is defined in many different ways, they all combine traditional story telling with digital media (images, audio, video, podcasts, etc.) to retell a story. The Bologna Process is encouraging technological innovation in teaching in Europe. DS is one of the genres that seem to match these expectations, as technology is prompting academics to reconsider their educational endeavor in terms of both content and teaching. DS is a versatile and flexible tool that can be implemented in almost all the subjects we teach and fulfill most purposes. Its adaptability comes from the fact that, depending on the goal of the activity and the student’s level of computer literacy, a digital story writer can use a variety of tools, ranging from the basic (like digital images and Photo Story) to the complex (like Flash to create their animations). Point of view, emphasis on the dramatic question, emotional state, the storyteller’s voice recordings, soundtrack, economy, and tempo, were the seven primary DS components recommended by CDS. Normann (2011) defines DS as a tale that lasts little more than two to three minutes and in which the narrator utilizes his voice to embellish the tale. The emphasis is on the private aspect, which could be connected to characters, a setting, an interest, or anything else that will give the narrative a personal touch. This has evolved in numerous ways because of improvements in recording and personal computing technologies as well as its use in a wide range of academic situations. DS is outlined by the DS Association, as a contemporary manifestation of the ancient art of story telling (the DS Association). Though there is no definitive explanation for DS, the bulk emphasizes the employment of multimedia tools together with graphics, audio, video, and animation to inform a story. Benmayor suggests DS as a brief multimedia system story that combines speech, image, and music (Benmayor, 2008). According to Kajder and colleagues, DS is a set of still images followed by a recorded soundtrack and they relate to a story (Kajder, et al, 2005). Meadows assumes the technology-focused meaning where DS creates brief transmission stories using computers, nonlinear authoring tools, and inexpensive digital cameras to complete social story telling projects. It is a technological tool that helps lecturers employ technology in their classrooms by implementing user-generated content (Meadows, 2008). Constructivist learning is the focus of DS. Different learning paradigms, including behaviorism, cognitivism, and constructivism, have been applied in recent years to improve the teaching and learning process. Each of these theories has its own take on learning methodologies. For instance, Hill claims that a learning theory is an effort to describe how individuals learn as well as a paradigm for comprehending the core elements of the learning process (Hill, 2008). The Psychonomic college supported by such scholars as Thorndike, Pavlov, and Skinner, assumed that learning promotes a new type of behavior resulting in out-of-classroom acts. Behavior models embody the employment of direction signs and learning observations. A behavior is performed on corresponding changes in discernible aspects of learning and the learning method. The important components of activity models are unit motivation, prompts, and the association between them. One of the foremost vital options is the incentive gift for learning at intervals in a learning setting. Compared with experimental psychology, which explores students’ behavior, psychological feature theories touch upon the processes driving the behavior. It places larger stress on the setting to facilitate the training method. Cognitivism focuses on the development, organization, and arrangement of instructional content facilitating the optimum management of knowledge, and how to recollect, store, and retrieve info. Additionally, learning is seen as a dynamic method, which is formed by the learners themselves (Skinner, 1974). Though contemporary constructivism dominates the educational paradigm, there are huge areas where it differs from the cognitive learning theory. It is distinguished by the emphasis on learning in real-world situations and attention to the social component of learning. It is according to Wilson, “a setting where students can collaborate and support one another as they use a range of tools and information resources in their supervised pursuit of learning objectives and problem-solving tasks” (Wilson, 1996). In addition, according to Anderson, the constructivist has more than a simple perspective on learning, recognizing that people explain the learned information and the world around them, based on their vision. In accordance with Jonassen’s opinion, learning environments ought to promote constructive, purposeful, active, cooperative, complex, dialogical contextualized, and reflective learning. Additionally, constructivism’s key learning qualities are that students build on their worldviews based on experience and interaction and that they create new understandings by assembling information from a variety of sources (Jonassen, 2012). On contrary, education theories created in the twentieth century view teaching and learning as more than just the exchange of information. These theories consider instruction as a particular paradigm of adult–child interaction, where the adult is ideally seen as a collaborator and/or co-constructor. The importance of the learners’ active role is highlighted heavily because it is essential for the development of abilities for lifelong learning. Leo Vygotsky created the zone of proximal development (ZPD) which is described as a gap between what a learner can perform with and without assistance (Vygotsky, 1978). The ZPD’s main goal is to make sure that students are actively involved in their education so that they can eventually become self-directed, lifelong learners. In this way, learning and teaching are two parts that jointly produce knowledge. Additionally, it makes it easier for that knowledge to be further transformed into the knowledge of each learner. DS facilitates an artistic approach to teaching and learning. It is a useful. educational tool because it provides a vehicle for combining digital media with innovative teaching and learning practices. Aside from building on learners’ technology skills, DS encourages further educational outcomes. It enhances learners’ motivation and helps academics in building constructivist learning environments that encourage artistic downside-finding supported collaboration and peer-to-peer communication. Additionally, DS is accustomed facilitate integrated approaches to program development and interaction with learners in higher-order thinking and deep learning. Current research is focused on the implementation of Web 2.0 tools in EFLT and it needs to be grounded on empirical foundations. Besides Web 2.0 technologies require users to have multiliteracies that are necessary for traditional paper-based activities (Sylvester & Greenidge, 2009). The term multiliteracies were introduced in 1996 by the New London Group to refer to the combination of literacies used now that allow people to successfully explore and adapt to information and communication technologies and contexts (Leu et al., 2004). In 2012 Nicky Hockly defined the term digital literacies as the constantly evolving digital landscape (Hockly, 2012). Furthermore, Dudeney et al. (2014) highlighted 4 main areas of digital literacies language-based, information-based, connection-based, and redesign-based literacies. Another opinion was proposed by Belshaw (2011) who characterized digital literacies as cultural, cognitive, constructive, communicative, confident, creative, critical, and civic. Students today merge text with other media like images, gifs, audio, and video locating and synthesizing information on the Web, communicating synchronously with others, and working in a nonlinear design. So, the modern digital approach of representing computer-assisted story telling for delivering specific information and sharing cultural ideas is determined as DS. Citing K. Brenner, DS contributes to getting knowledge via using various media such as animation, audio–video, graphics, web sites, so that to read, listen, see and act (Brenner, 2012). She realized not only her idea so that to demonstrate how to include the DS technique into the teaching process, but Brenner has organized a DS lab. Most of her suggestions DS technique is a project based assignments lasting from 10 to 12 weeks that is intended to increase personal abilities including teamwork, leadership, and time management. Analyzing collective research conducted by Condy, Chigona and other scientists, DS is highlighted as a powerful tool in teaching students with different learning styles, it suits visual, auditory, and kinesthetic students. This tool strengthens learners’ creative, critical thinking and cognitive skills in designing and making DS colorful and unique while collaborating and working in a team. Description of the methodology Research context The given case study represents the strengths and weaknesses of implementing DS in University endeavors and describes the Web 2.0 tools to make and narrate own stories, and how they can be used for educational purposes. The increasing popularity of Web 2.0 tools in the pandemic COVID-19 situations around the world highlighted their huge educational capabilities. The main purpose is to investigate the benefits of using DS in distance education and its impact on teaching and learning and raise certain difficulties for pre-service teachers in designing their own DS. The main purpose of the current study is to explore the effectiveness of public speaking skills by describing methods and strategies for using digital media for storytelling in multilingual classrooms. Besides, sub-objectives were to look at whether the different scopes and areas in which academic public speaking skills with the help of the DS could be integrated as a significant source in academic speaking and to improve students’ public performances of multilingual groups which benefit them when applying their knowledge and performances in their professional endeavor. DS is a process of creating a typical story in a digital version that revolves around the narrative. Students write multiple drafts and receive peer reviews during story circles. After the narrative is completed, students develop a script, a refined version of the narrative that is recorded later. Then students put together a storyboard to align their script with visuals and videos from personal life or online resource, YouTube channels. DS creating is conventionally done using video editing software such as iMovie, and Movie Maker. Finally, students share their digital productions with peers and demonstrate them in the English classroom. In addition, DS videos were created that were accustomed to support DS’s instructional use. Also, a discussion of challenges and different vital issues that students and instructors ought to bear in mind before implementing the DS within the learning area unit is enclosed and conclude with an outline of the analysis that has been and desires to be conducted on the effectiveness of DS as an effective learning device for education. DS is a beneficial way of telling/making stories using animation, website, audio video, and graphics. Students create their own stories with images, and scripts on cultural differences/similarities in English, Russian and Kazakh communication. The effect of DS creating on the L2 comprehension ability of university participants was determined with the questionnaire. It examined the motivating impact of L2 acquisition of a given linguistic and cultural aspect. The results showed that students produced language and cultural awareness skills while communicating more significantly than before our practical approbation. What’s more, the results of the current study provide that the teaching language and culture are closely intertwined and shift teaching language into cultural interaction. Nevertheless, high schools’ graduates have usually not reached level B1 because of their lack of communicative context, shortage of learning motivation, and testing pressure (Nguyen & Huan, 2018). So, the urgency of this research is to promote teaching conditions via DS for improving academic speaking skills in public pre-service teachers. The article reports on a small-scale study that examined the impact of enhancing cultural diversity in English language learning (L2) due to DS implementation at the Eurasian National University, Nur-Sultan, Kazakhstan, for second year students on the specialty “Foreign Languages: two foreign languages” over 7 weeks. 7 weeks had been scheduled for data collection. Participants profile 60 pre-service teachers during the autumn term of 2021 were involved in the experiment. The participants were 19–20 years old learners of different nationalities: Kazakh, Russian, Tatar, Uzbek, German, Polish, Korean, Kirgiz, Ukrainian, Chinese, etc. They master their native language, the language of communication either Kazakh or Russian, and less than one foreign language. In total, 60 students took part in the experimental training. At the time of implementation, all students studied two foreign languages (English and German/French/Chinese/Spanish). “Public speaking skills” was a subject that participants went into that particular period of time according to the syllabus of the given specialty. It is obvious; that this discipline was the most pivotal one for our students. According to the requirements of national standards, the students should be prepared for four main activities listening, reading, writing, and speaking. The topics of speaking dealt with cultural problems focusing on their own experience and national events. Noteworthy the participants were divided into two groups: subgroup “CG”—a control group and subgroup “EG”- an experimental group, with 30 students in each. The academic proficiency of both groups was high enough. Subgroups CG and EG overall had the same scores in reading, listening, writing, speaking, and level of academic knowledge in specific disciplines. In the control subgroup CG, students were approximately of the same age (19–20 years old), and 16 students were bilingual, based on the responses to our survey. Sixteen of them were students of Kazakh nationality (including 6 bilinguals), and four were students of Russian nationality. Students in the control subgroup were taught according to the 10-week implication DS model. Despite nationality, only 5 bilinguals were trained in the experimental group, according to the questionnaire. Two more students studied Russian from the school bench, and the remaining six students are Russian-speaking and studied the Kazakh language at school. Nevertheless, the control group had a traditional teaching approach. The traditional teaching approach meant classical training with the help of textbooks and audio–video supplementary materials. Subgroup EG had an experimental teaching approach to implementing DS. Seventeen students of Kazakh nationality and three students of Russian nationality studied in the EG subgroup. All students spoke Kazakh in the framework of the curriculum except for bilinguals according to the questionnaire. Both groups the control and experimental subgroup consisted of 30 students who were also students at the same University. For all participants in the control and experimental training, English was the first foreign language. Learning a second foreign language starting from the third year of study. All designated students in the control and experimental groups were studying according to the educational program with the Kazakh and Russian languages of instruction. An empirical study revealed partially variable and no variable conditions for conducting experimental training. No variable conditions included: (1) the same number of studied foreign languages in CG, and EG; (2) the same number of hours allocated for teaching foreign languages in CG and EG; (3) approximately the same initial level of learning foreign languages of subjects of the experimental and control groups; (4) the equal tools and forms of assessment. We attributed to partially non-invariant conditions: (1) the same occupancy of groups (30 people); (2) the same length of the period of learning the second foreign language; (3) the equal teaching materials and work program. Variable conditions included: (1) the application in experimental groups of an author’s methodology for the formation of multilingualism skills in students when they learn several foreign languages, (2) the formation of multilingualism skills for students not only in foreign language lessons, but also through the organization of student’s independent work, and (3) using different types of work (individual, pair, group work in the EG, and individual self-work in the CG). As a result, we concluded that the students being observed in this research were fourth-year students at the University of the foreign language department. None of them are native English speakers. The racial demographics of students from the control and experimental groups largely comprised two groups—native Kazakh speakers (36%) and native Russian speakers (58%). But it is also important to point out that native Kazakh language speakers preferred to get an education in Russian language groups. Classes included 10–12 students. The English proficiency levels of the English language learners range from upper-intermediate (22) as it was determined by the proficiency exam. Additionally, we worked out the definite criteria for achieving academic public speaking skills in n culturally diverse context. Cited to M. Hogan who highlighted the most useful skills of cultural diversity competence as known as cultural awareness, successful interpersonal techniques, and tolerant behavior. An umbrella term he had defined as cultural diversity competence (Hogan, 2013). According to Hogan’s research, it was stated that because of updated challenges, higher education plays a crucial role in helping people to discover their personal identities, the historical and cultural peculiarities of their native area, and to recognize the factors that have shaped and continue to shape their lives. In a nutshell, representatives of large national groups should desire to explore the differences of other ethnic groups since it is the only way to enrich their social and enhance their understanding of the multicultural challenges facing the world today. Hence, we applied his suggested parameters of cultural diversity skills in assessing students. In our experimental teaching, we encouraged our students to become culturally competent in today’s diverse environments. Thus, the problem tackled in the given research is of huge importance. So, we put the following statements to prove during our experimental teaching. Our research questions were:Can DS be used in classrooms with diverse nationalities and languages? Is it possible for multilingual students to develop their linguistic, cultural, and organizational skills through DS learning activities? How can DS foster a collaborative environment where students can actively participate and share ideas, and carry responsibility for completing academic goals in literary public speaking? The procedure We used DS in the English Language Classroom for pre-service teachers. We tried to develop students’ academic public speaking because DS is highly beneficial in comprehending new knowledge and improving digital and grammar literacy which totally means contributing to developing the oral skills of the students. DS is a novice emerging concept that describes the new practice of everyday people who use digital tools to tell their stories. Digital stories ensure digital interactive plots with compelling and emotionally engaging formats. The DS invention consists of a huge number of Web 2.0 tools like hypertexts, narrative computer programs, interactive stories, making videos, web-based stories, voice recording, and infographics. The experimental teaching had several stages lasting 7 weeks depicted in Scheme 1 The main theoretical background in our methodological model of implementing DS in the culturally diverse multilingual classroom was based on key notions by K. Brenner (2014).Scheme 1 Methodological model of implementing DS Totally during experimental teaching, we aimed at improving cultural awareness, successful interpersonal techniques, and tolerant behavior as cultural diversity parameters and aspiring academic public speaking for TEFL Pre-Service students. Therefore, the experimental course of implementing DS for 7 weeks was organized as follows: In the first introductory phase Week 1—when students were supposed to decide on the topic of their stories and make initial drafts. Week 1 was a preparatory one that concluded with choosing a topic and purpose. In the first lesson, we created a visual problem of the story or global issue. Things like politicians speaking, televised debates, and celebrities show where there are several people around a table discussing something were useful. Here we used YouTube resources. We aimed for our students to be attentive to body language gestures, zone, and speaking manners so that to interpret the thoughts of people from native and foreign cultures. The DS was the most long-lasting and time-consuming both for the students and tutors because we need to choose video for any global issues with meeting people from the target culture and mother culture as was pointed out in the report about using Web 2.0 digital stories by Alameen (2011). In our case, students had decided in a group that stories should be about cultural differences and similarities, experiences of celebrities, events, etc. that inspired them, or about people whom they admired. Moreover, all stories should concern different cultures, traditions, beliefs, aspects of nonverbal communication, etc. Besides, we demonstrated innovative software programs, websites, web applications, etc. Whether or not there was a software demonstration, students watched DS as examples that were available on the Internet. Additionally, students were given an extensive list of web resources to assist in the experimental teaching. The most favorite was iMovie, Windows Movie Maker, Splice, Clips, Video Star, Viv video, Flip gram, and Voice Thread. TEFL Pre-service students identified the fundamental elements of a good DS and reviewed examples, by the end of week 1, they chose a topic and define the purpose of the story they want to create for a classroom. Getting students to focus on these factors helped to raise their awareness of the diverse cultural communication which was happening. What is more, in the first week before our experimental teaching we assessed skills of cultural diversity such as cultural awareness, successful interpersonal techniques, and tolerant behavior. The skills under the experiment were measured with the help of rubrics. Precisely we evaluated their initial cultural diversity due to academic public speaking focused on descriptors such as language fluency, linguacultural coherence, and cohesion, grammatical and lexical accuracy, pronunciation, willingness to communicate, communicative strategical skills, and abilities to discuss. Week 2 introduced me to the basics of DS and was devoted to writing an effective script and creating a storyboard. We focused on scriptwriting as learning the steps in writing a script for DS. TEFL Pre-service students explored the basic elements of a script, such as introduction, character development, tension, and resolution that were necessary for developing a useful script. By the end of this week, they began to understand the important steps and elements of scriptwriting. A point to note is that TEFL Pre-service students recognized the importance of selecting appropriate cultural images and the value of creating a storyboard by further acquiring new web technologies. During Week 2, they explored several useful ways to choose images for DS, including taking their photos from real life with a digital camera, using software applications to create charts, graphs, and other images, and finding and downloading images from the web-based on size, quality, type, and usage rights. The second phase was dedicated to the verification of the final draft by a tutor. During the last phase of the project, students performed their own digital story with a public presentation (See Table 1). A step-by-step approach was used to illustrate how these images support script and cultural differences between native and foreign communication and to identify their similarities and differences as a part of DS creation. By the end of this week, TEFL Pre-service students created their own story's script in a visually interesting and useful storyboard. We familiarize TEFL Pre-service students with rubrics for assessing DS which focus on linguistic abilities, and technical creativity namely narrative voiceover, images, photos, audio soundtrack, and students’ performance and public speaking skills parameters as fluency and coherence, cohesion, grammatical and lexical accuracy, pronunciation, and abilities to discuss (Table 2).Table 1 Participant’s profile № Nationality Number Native language Target language 1 Kazakh 33 Kazakh English 2 Russian 7 Russian English 3 Uzbek 5 Uzbek English 4 Ukrainian 3 Russian English 5 Chinese 2 Chinese English 6 Tatar 2 Russian English 7 Korean 2 Russian English 8 Kirgiz 2 Kirgiz English 9 German 1 Russian English 10 Polish 1 Russian English 11 Armenian 1 Armenian English 12 Vietnamese 1 Vietnamese English Total 60 Table 2 The rubric of DS Evaluation No Criteria Points 1 Structure The number of slides corresponds to the content and duration of speeches (for a 4–5-min speech, it is recommended to use no more than 8–12 slides) 20 points The presence of title slides and a slide with conclusions An overview of the content is provided Student and instructor info provided 2 Visibility Illustrations with good quality, clear images, the text is easy to read (not too much text per slide or its too small to read) 15 points Use visuals to support work and main speaking points (screenshots, screen captures, video clips, pictures of slides from presentations, etc.) Student is on screen and the camera is focused 3 Design and customization The design of the slides corresponds to the theme, and does not interfere with the perception of the content, the same design template is used for all presentation slides 15 points Creativity and originality are demonstrated 4 Content The presentation reflects using the 4-level model of reflection for the course (before, during, after, going forward) 15 points Contains complete, understandable information on the topic At least 3–4 examples demonstrated through pictures or video Student provides meaningful insight into the future practical application of content beyond just a generalized mention 5 Requirements to the speech The student is fluent in the content, and clearly and competently presents the material 20 points The student freely and correctly answers questions and comments from the audience The student fits exactly into the time limit (4–5 min) The student is expressive of personal feelings and discusses the “how” and “why” and is not overly focused on the general theory 6 Requirements to the video The video must be live, i.e., be present with the camera on 15 points At the same time, the presentation should reflect both the student's video and the presentation Excellent video recording quality Clear sound and language used Maximum points 100 points One of the groups was the most advanced so we asked them to collect visual, audio, and other sensory materials to create a story using Animoto and iMovie video creation services. Week 3 was devoted to recording audio narration. We recorded audio narration using digital devices so that students’ voices could be added to the DS they created. They gained hands-on experience using some of the most common features of audio recording software to create a high-quality audio narration. In addition, students explored ways to improve audio recording with basic editing tools. Also, they learned how to find and download appropriate music for a digital story that is in the public domain or is free of copyright restrictions. The week was the most complicated because Pre-service students recorded an infinite amount on different days and they were disappointed in their pronunciation, stress, tone, intonation even their voices. So, recording the voiceover was the most frustrating moment of our experimental teaching. In week 4, we learned how to use We Video, a free online video editing application to assemble all the elements such as text, images, narration, and music to create the full version of students’ DS. In addition, they learned to use basic editing techniques to improve their DS so that all the components of the story fit together and look and sound good. Week 5 was devoted to revising, publishing, and sharing the final DS for use in the classroom. In week 5, Pre-service students revised the final version of their DS published it online and discussed how it might be used in the classroom to support teaching and learning. Week 6 was the endpoint of our experimental teaching. The students represented their DS as an oral l public presentation consisting of an introduction, the main body, and a conclusion. Pre-service students had an opportunity to reflect on the DS process and discussed the challenges they faced, how they dealt with these challenges, the most significant things they learned during the course, and how they thought they might use DS in the classroom. The students wrote the final essays, delivered info and links with peers, evaluated themselves and the teacher, and reflected on the new approach. During speaking tasks students mastered skills of cultural diversity such as cultural awareness, successful interpersonal techniques, and tolerant behavior. The DS requirements were discussed beforehand as a well-organized storyboard and crucial topic. Pre-service students were given approximately 4 min and limited to 15 slides, 20 images, and a volume of no more than 650 words. The Soundtrack was optional. It must be mentioned that all Pre-service students did their best, and all of them tried to implement the elements they intended to. In addition, we assessed Pre-service students’ DS with an oral presentation in public according to rubrics that evaluated the following criterion: linguistic abilities, technical creativity namely narrative voiceover, images, photos, audio soundtrack, and students’ performance. Week 7 was the final summarizing week of the efficiency of implementing DS in the English lessons for multicultural students. This week as in the first week, after our experimental teaching, we checked skills of cultural diversity as cultural awareness, successful interpersonal techniques, and tolerant behavior. And we evaluated their initial public speaking skills with the help of rubrics focused on descriptors such as fluency and coherence, cohesion, grammatical and lexical accuracy, pronunciation, and abilities to discuss. The empirical classes dealt with diverse tasks and exercises aimed at improving academic speaking skills. All the activities were conducted to extend academic vocabulary and develop speech to make it precise and fluent as well as expand the knowledge of grammatical constructions. The students shared ideas, expressed their own opinions, and tried to find solutions in their small discussion groups. The students were involved in agreeing or disagreeing discussions providing their solutions. It is essential in this case that the student tried to form conversational skills. In addition, these activities fostered to development of critical thinking of students and decision-making, and students learned how to express and justify themselves in polite ways while disagreeing with others. Furthermore, the students were always encouraged to ask questions, paraphrase ideas, express support, check for clarification, and so on. It was apparent, that such activities were beneficial and efficient because everyone had the opportunity to speak and make their speeches fluent. During DS activities students dealt with the writing section. A huge amount of time was devoted to narrative writing because the multilingual groups had difficulties in the formation of written speech. The aim was to draw much attention to the accurate way of writing including coherence and cohesion. The DS pursues the continuous repetition of utterances based on paraphrases and synonymy. The tasks embraced the different statements where students had to provide their relevant variants considering linking words, expressive means, emphatic constructions, and so on. The latter constructions, elliptical constructions are those which help students make their essays authentic and relevant to the English language. Results and discussion During 7 weeks of the study, the students explored several useful ways to create a storyboard, choose images for DS with the inclusion of taking their photos from real life with a digital camera, use software applications to create charts, graphs, and other images, and finding and downloading images from the web-based on size, quality, type, and usage rights, making voiceover, recording again and again. When our experimental teaching was completed, we began to analyze the whole pre- and post-experimental results and findings. Firstly, before our experimental teaching of implementing DS in the multicultural classroom, we conducted a pre-experimental questionnaire (September 2018) to the 60 participants (Figs. 1 and 2).Fig. 1 Satisfaction of cultural diversity and oral speaking performance in syllabus Fig. 2 IT usage in foreign language learning Chart. 1 Pre-experimental testing on cultural diversity in CG and EG Chart. 2 Post-experimental testing on cultural diversity in CG and EG The questionnaire aimed to reveal students’ attitudes to academic speaking skills teaching, the completeness of the syllabus, and the level of using computer-assisted technologies in the classroom. So the information was collected in the following areas:Cultural diversity in the syllabus and oral speaking performance (Fig. 1); Students’ satisfaction in using IT technologies in learning foreign languages (Fig. 2). These dimensions were investigated using a four-level scale: + + very positive, + positive, − negative, − very negative. Analyzing Fig. 1, from 60 questionnaires the satisfaction of cultural diversity that studied according to syllabus and development of oral speaking performance Pre-service students had the very positive evaluator 21%, 34%—positive. Totally just over the middle of all students were satisfied with the existing syllabus and its presentation of public speaking and cultural diversity. It was clear that University appreciated the cultural diversity in the syllabus. The limited number of students, 13%, had very negative indicators, and 32% had—a negative attitude. Analyzing Fig. 2, from 60 questionnaires about the satisfaction of using IT in the English classroom only 10% answered they had a very positive indicator, 30%—positive, and, remarkably, the most prevailed percent was negative, 36%. 24% of Pre-service students had a very negative evaluator. It meant that IT technologies in learning foreign languages were applied a little in the classroom. The valid 60 questionnaires are represented in Figs. 1 and 2 So after having analyzed both questionnaires we proposed to organize the academic public speaking teaching with the help of DS in the lessons for multilingual Pre-service students.Moreover, during our experimental teaching on exploring DS in a multilingual classroom, we organized and prepared a variety of assessments on cultural and academic public speaking skills. Then the second assessment rubrics were fostered to evaluate the cultural diversity skills during the experimental 7 weeks of teaching. As was mentioned above, we conducted pre-experimental and post-experimental testing to check how students mastered cultural diversity skills such as cultural awareness, successful interpersonal techniques, and tolerant behavior in Chart 1 and Chart 2. This experimental teaching focused on the interrelations between learning a foreign language involving culture and technology. Chart 1 illustrated the results of pre-experimental testing on cultural diversity in two groups: CG and EG. The first one “CG” was taught according to the traditional teaching approach. The second "EG" used DS in teaching. As is shown in Chart 1, the indicator of cultural awareness group “CG” had 22%, and group “EG”—had 21%. With the mastering of interpersonal techniques in cultural communication students of both groups, “CG” and “EG” had 30%. The dimension of tolerant behavior in group “CG” was 48%, and in group “EG”—49%. Both groups had equal parameters. As the study examines the impact of enhancing cultural and linguistic diversity in English language learning due to implementing DS for second year Pre-service students over 7 weeks, we analyzed in what way DS allowed students to create their own stories with images, scripts on cultural differences, and similarities in native and foreign communication. The results were demonstrated in Chart 2. Chart 2 illustrated the results of post-experimental testing on cultural diversity in the “CG” and “EG” groups. As we saw in Chart 2, the indicator of cultural awareness group “CG” had 20% while group “EG” improved to 23%. The next parameter of interpersonal techniques in cultural communication students of group “CG” had the previous 30% but group “EG” developed as 32%. The tolerant behavior in group “CG” was 50%, and in group “EG”—45%. The purpose of implementing DS in the multilingual classroom was to create all parameters equally aligned. Comparing Chart 1 and Chart 2 we summed up that parameter of developing cultural diversity had dynamics and changed in “EG”. For example, the dimensions of cultural awareness enhanced from pre-experimental teaching 21% to post-experimental 23%, also, and interpersonal techniques improved from the initial stage 30% to final 32%. Generally, there were no significant differences in developing cultural diversity criteria in “CG” while in “EG” almost all parameters had changed. It meant that the main indicator of cultural diversity skills as cultural awareness, successful interpersonal techniques, and tolerant behavior had a perfect result. Additionally, the results showed that students in “EG” produced gestures, facial expressions, and eye contact with more consciousness while communicating and developing a conceptual framework. Cultural diversity skills were represented as cultural awareness of different nations and traditions, cultural behavior toward various beliefs and customs, and tolerance which means appreciating diversities. So, it is suggested that DS is a powerful way of telling and making stories using animation, website, audio video, and graphics. Moreover, DS enhances the second year pre-service TEFL students listening, reading, speaking, and writing skills in the target language especially it helps them understand information and develop vocabulary. Taking into consideration the speaking section, “EG” students were involved in implementing 3 main parts: the response to several questions, the response to the whole topic with the given plan, and the response to the different abstract questions. According to the DS techniques, the students were engaged in multiple reiterations of the necessary and relevant vocabulary and the variety of grammar, they were concentrating on the authentic way of speaking. Moreover, the focus of the practical training was to pay students attention to the authentic expression of ideas not the mental translation from their native languages such as Kazakh, Russian, Korean, Polish, Uzbek, etc. Huge attention in training was paid to the improvement of communicative skills. Besides we made a pre-experimental data analysis of the student’s academic public speaking skills before the experiment to check the initial data in both groups as “CG” and “EG” (Table 3).Table 3 The data of students’ academic public speaking performances before the experiment Score (points) 95–100 90–94 85–89 80–84 75–79 70–74 65–69 60–64 55–59 50–54 0–49 A A− B + B B− C + C C− D + D F Control group (%) 8 16 16 15 14 12 11 8 – – – Experimental group (%) 6 14 15 13 13 14 13 10 2 – – After 7 weeks of experimental teaching, we conducted a post-experimental data analysis of the student’s academic speaking skills to check them (Table 4).Table 4 The data of students’ academic public speaking performances after the experiment Score (points) 95–100 90–94 85–89 80–84 75–79 70–74 65–69 60–64 55–59 50–54 0–49 A A− B + B B− C + C C− D + D F Control group (%) 8 16 16 15 14 13 12 6 – – – Experimental group (%) 8 15 16 14 14 13 10 10 – – – The academic vocabulary and grammar were permanently reiterated by different speaking exercises, and it gave a golden opportunity to develop students’ skills in the experimental group. Noteworthy, students revealed the value of eye contact, facial expression, proximity, and gesture in their endeavours and foreign ones. The effect of using video context in DS on the listening and speaking comprehension ability of university pre-service students was positively influenced during experimental teaching. It examined the impact of DS production on developing cultural components via communication in native and foreign languages and the acquisition of a given video in the second language. Many students, especially when listening to a second language, focus so heavily on hearing and understanding 'the words people are saying that they suffer from a form of cognitive overload. There is just too much incoming information for them to process and they miss many of these subtler messages. When we deal with listening in class, this is mostly done with the use of recorded text on an audiotape or CD, so these more visual factors in the communication are neglected in our students' second language development. Many of these traits of communication can have different meanings or be interpreted in completely different ways in different cultures. More interestingly, however, the results of the current study if components of cultural diversity effectively supplement the information conveyed via speech but could not replace it. We chose the descriptors of evaluating academic public speaking as fluency and coherence, cohesion, grammatical and lexical accuracy, pronunciation, and abilities to discuss. These descriptors were structured in the rubric. The results of academic public speaking tests via rubric before the experiment were counted by 100 points assessment system that is used at the University as the highest score. As far as it is seen, the control group passed the tests more successfully and got higher scores than the experimental one. The evaluation of students in the experimental group showed improved skills in cultural diversity as cultural awareness, successful interpersonal techniques, and tolerant behavior. In comparison, 95–100 points were received by only 6% of students in the experimental group but in the control group—8%. 60–64 points in the experimental group were 10% compared to the control group at 8%. 55–59 points scored 2% in the experimental group. However, there are a couple of girls who eagerly arrange all class activities and keep the students united. They are the most responsible people who are ready to help with any arrangement. Overall, the students are well-mannered. They do not unitize obscene language, at least, in the teacher’s presence. At the lessons, one part of the group is active and loud, but another part is quite silent. A teacher has to make effort to arouse them from their indifference. The subject matter of texts and assignments meets the student’s needs and interests in compliance with claimed age. Many students have a B2 level of English proficiency. A step-by-step approach was used to illustrate how these images support script and cultural differences between English/Kazakh/Russian communications and to identify their similarities and differences as a part of creating a digital story. Then they recorded audio narration using digital devices so students’ voices could be added to the digital story they created. By the end, students created their own story's script in visually interesting issues from the target and mother culture and defended it in the classroom. Finally, the effect of video and audio context on the listening and speaking comprehension ability of university students was determined with the assessment rubrics. The results showed that participants mastered new technology which helped them to promote the acquisition of certain knowledge of foreign language content and require new skills in a better and more relevant way. After experimental teaching both groups, we conducted academic public speaking tests with the help of an assessment rubric and got the following results described above in Tables 3, 4. The results of the academic public speaking skills test after the experiment were counted by 100 points assessment system that is used at the University as the highest score. As far as it is seen, both the control and experimental groups passed the tests nearly equally. More successfully were the students from the experimental group because they got the same scores of 95–100 points. The experimental group received 10% of students in the experimental group in 65–69 scores just as in the control group 12%. The experimental group improved their scores, and nobody got 55–59 points. In comparison with the control group, the moderated average variance of the experimental group is higher in many scores. The results pointed out that all participants of the control group had made some improvements after the study, though, this improvement was not as huge as the one made by the experimental group learners. The average variance of the experimental group was superior to that of the control group showing that DS effectively enhanced the public speaking performances of the students at the University multilingual groups and improved their cultural skills. To sum up, we illustrated their reflection as “It was one of the most entertaining activities during the term”, “All students seemed to be actively engaged in the process, everyone did his/her best as they could”, and “Only Positive feedback”. Last but not the least, teaching language and culture are closely intertwined and shift to teaching language in cultural interaction. In fact, the Rubric of DS evaluation was constructed for marking students’ DS which helped to identify the extent of their public speaking skills progress. The findings of this study reflected that EFL pre-service students in EG had improved their public speaking skills. They had designed DS, created a plot, used vocabulary and grammar in culturally diverse practice, and summarized it. The students got the skill of paraphrasing stories and gained confidence in speaking publicly with proper pronunciation after practicing it a lot for narrating a story. Conclusion In the context of the present study, we defined DS as the learning process by which culturally diverse people shared their life stories and creative imaginations with others. This newer form of storytelling emerged with the advent of accessible media production techniques, hardware, and software, including but not limited to digital cameras, digital voice recorders, iMovie, Windows Movie Maker, and Final Cut Express software. These new technologies allow individuals to share their stories over the Internet on YouTube, Vimeo, compact discs, podcasts, and other electronic distribution systems. DS is a powerful way of telling/making stories using animation, website, audio video, and graphics. Students created their own stories with images, and scripts on cultural differences/similarities in English, Russian and Kazakh. Besides DS environment promoted lifelong learning. The effect of creating DS on the L2 comprehension ability of the participants was determined with the questionnaire. It examined the motivating impact of L2 acquisition of a given linguistic and cultural aspect. The results showed that the students produced language and developed cultural awareness skills while communicating more significantly than before our practical approbation. What’s more, the results of the current study provide that the teaching language and culture are closely intertwined and shift from teaching language into cultural interaction. Quite apart from the emphasis put on lifelong learning and the acquisition of ICT skills in all areas of education in many countries, we are teachers of the language of global communication. And that communication is increasingly digitally mediated. If learners are to be fully functional citizens in the twenty-first century, they need digital skills. We can promote these skills in parallel with teaching English. Digital skills and English help many adult learners get ahead in the workplace or prepare our younger learners for better future job opportunities. And equally important, they can make our classes a lot more relevant and interesting in the here and now. Integrating digital literacy work into our English classes can make them a little more relevant to who we are learners once they are outside the learning environment. In this article, we reviewed the DS characteristics and argued in favor of using it as an instructional tool in teaching EFL. We first provided a description of the characteristics and elements that form the structure of digital stories, and then proceeded to illustrate some of the possible uses of digital storytelling in the classroom The last part of the article included a description of a digital personal project that is currently under development and that involves the creation of personal narratives. Notwithstanding the impact of the use of digital storytelling as an instructional tool, digital storytelling is still under survey and a lot of work needs to be done until both students and teachers become familiar with the genre itself. But, although there may be some negative outcomes when using digital storytelling as an instructional tool, so far, we have seen more positive aspects and we would therefore give digital storytelling the benefit of the doubt. It’s a good way to design information and a pedagogical tool that is worth looking into. Further implications Now that we have looked at the entire data meticulously, we state Digital Storytelling is used as a teaching and learning tool in a multilingual diverse classroom. It is one of the ways teachers can understand students’ outlooks. There is no doubt that it is time-consuming, but it helps to develop skills such as Research Skills; Writing Skills; Organization Skills; Technology Skills; Presentation Skills; Interview Skills: Interpersonal Skills; Problem-Solving Skills: Assessment Skills, and literacy: Digital Literacy; Global Literacy; Technology Literacy; Visual Literacy and Information Literacy. The findings of the DS study proved that DS is a highly recommended tool for EFLT, especially when we consider academic public speaking skills in the culturally diverse multilingual classroom. Our students enjoyed the DS activity as demanded technical and artistic involvement. It is believed that there is more that needs to be learned about Digital Storytelling as a teaching and learning tool for language learning classrooms, including target languages that are different from EFL, e.g. Chinese, Russian or Spanish. More examples of providing greater insights and understanding into how Digital Storytelling can engage, inform, and enlighten new generations of students and educators will be found. Due to time constraints, the research was done from a specific level with a smaller number of students. Further research activities can be done in the future to gather more data on the same topic. DS is very useful for promoting learner autonomy strategy. Declarations Conflict of interest The authors declare that they have no conflict of interest. Ethical statement The present study was approved by the ethics committee of the Faculty of Philology, L.N. Gumilyov Eurasian National University, Astana city, Kazakhstan. The experimental process was explained to all participants by the researchers in the beginning of the study. In addition, the researchers explained that the research data will be collected, anonymized and used by the researchers in their report and research article. After that, the participants provided an informed consent to participate in the study. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Alameen G Learner digital stories in a web 2.0 Age TESOL Journal 2011 2 3 355 369 10.5054/tj.2011.259954 Aronin L Singleton D Affordances and the diversity of multilingualism International Journal of the Sociology of Language 2010 205 105 129 Belshaw D What is digital literacy? 2011 Department of Education at Durham University Benmayor R Digital storytelling as a signature pedagogy for the new humanities Arts Humanities High Education 2008 10.1177/1474022208088648 Brenner, K. (2014) Digital Stories: A 21-st Century Communication Tool for the English Language Classroom. English Teaching Forum, Number 1, USA, 22–29 https://americanenglish.state.gov/files/ae/resource_files/6dkyilyaxnygsh0lywlri3bhf.pdf Capra F Complexity and life Theory, Culture and Society 2005 22 33 44 10.1177/0263276405057046 Cenoz J Towards multilingual education: Basque educational research in international perspective 2009 Multilingual Matters Condy J Chigona A Gachago D Ivala E Pre-service students perceptions and experiences of digital storytelling in diverse classrooms Turkish Online Journal of Educational Technology-TOJET 2012 11 3 278 285 Cummins J Instructional conditions for trilingual development International Journal of Bilingual Education and Bilingualism 2001 4 1 61 75 10.1080/13670050108667719 Dewaele J-M Multilingualism and affordances: Variation in self-perceived communicative competence and communicative anxiety in French L1, L2, L3 and L4 IRAL 2010 48 105 129 10.1515/iral.2010.006 Dudeney G Hockly N Pegrum M Digital Literacies 2014 Routledge Duffy J Lowyck DH Jonassen S Designing environments for constructive learning 2012 Springer Publishing Company Edwards J Multilingualism 1994 Routledge Guillermina G Oliver McGarr Exploring pre-service teachers’ future intentions to use technology through the use of comics Teaching and Teacher Education 2019 83 99 109 10.1016/j.tate.2019.04.004 Hill WF Learning: A survey of psychological interpretation 2002 Allyn and Bacon Hockley N Digital literacies ELT Journal 2012 66 1 108 112 10.1093/elt/ccr077 Hogan M Four skills of culturally diversity competence: a process for understanding and practice 2013 Fourth Edition Brooks, Cole Cengage Learning Hwang WY Shadiev R Hsu JL Huang YM Hsu GL Lin YC Effects of storytelling to facilitate EFL speaking using Web-based multimedia system Computer Assisted Language Learning 2016 29 2 215 241 10.1080/09588221.2014.927367 Kajder, S., Bull, G., & Albaugh, S. (2005). Constructing digital stories, in learning & leading with technology. Krashen S Under Attack: The case against bilingual education 1996 Language Kunanbayeva SS The modernization of foreign language education: the linguocultural-communicative approach 2016 Almaty Lambert, J. (2009). Where it all started: The center for digital storytelling in California Leu, D., Kinzer, Ch., Coiro, J., & Cammack, D. (2004). Toward a Theory of New Literacies Emerging from the Internet and Other Information and Communication Technologies. Theoretical models and processes of reading. 5th ed. International Reading Association Meadows, A. (2008). A Guide to Digital Storytelling by members of the BBC Capture Wales Team. March 2008 Nguyen L Nguyen HB The impact of storytelling on high school resources students’ oral performance Journal on English Language Teaching 2018 3 4 76 Normann A Digital Storytelling in Second Language Learning, in Faculty of Social Sciences and Technology Management 2011 Norwegian University of Science and Technology Project. Indigenous Education Institute and UC Berkeley Space Sciences Laboratory. http://cosmicserpent.org/uploads/downloadables/DigitalStorytellingforCrossCulturalCommunication.pdf Search, P. (2015). Digital Storytelling for Cross-Cultural Communication in Global Networking. Cosmic Serpent. Available from: https://www.yumpu.com/en/document/read/49342150/digital-storytelling-for-cross-cultural-cosmic-serpent Shadiev R Huang YM Hwang WY Liu TY Cognitive diffusion model: Facilitating EFL learning in an authentic environment IEEE Transactions on Learning Technologies 2017 10 2 168 181 10.1109/TLT.2016.2574356 Shadiev R Liu JW Review of research on applications of speech recognition technology to assist language learning ReCALL 2023 35 1 74 88 10.1017/S095834402200012X Shayakhmetova L Mukharlyamova L Beisembayeva Zh Zhussupova R Developing collaborative academic writing skills in English in CALL classrooms International Journal of Higher Education 2020 9 8 13 18 10.5430/ijhe.v9n8p13 Skinner BF About behaviorism 1974 Jonathan Cape Sylvester R Greenidge W Digital storytelling: Extending the potential for struggling writers The Reading Teacher Journal 2009 63 4 284 295 10.1598/RT.63.4.3 Vygotsky LS Mind in Society: The development of higher psychological processes 1978 Harvard University Press Wilson BG Constructivist learning environments: Case studies in instructional design 1996 Educational Technology Publications Zhussupova RF Kazbekova M Metacognitive strategies as points in teaching reading comprehension procedia—social and behavioral sciences Elsevier 2016 228 593 600 10.1016/j.sbspro.2016.07.091
PMC009xxxxxx/PMC9940066.txt	==== Front Hypertens Res Hypertens Res Hypertension Research 0916-9636 1348-4214 Springer Nature Singapore Singapore 36805031 1232 10.1038/s41440-023-01232-y Article Hypertensive emergencies and urgencies: a preliminary report of the ongoing Italian multicentric study ERIDANO Vallelonga Fabrizio [email protected] 1 Cesareo Marco 1 Menon Leonardo 1 Leone Dario 1 Lupia Enrico 2 Morello Fulvio 2 Totaro Silvia 2 Aggiusti Carlo 3 Salvetti Massimo 3 Ioverno Antonella 4 Maloberti Alessandro 5 Fucile Ilaria 6 Cipollini Franco 7 Nesti Nicola 7 Mancusi Costantino 6 Pende Aldo 4 Giannattasio Cristina 5 Muiesan Maria Lorenza 3 Milan Alberto 1 1 grid.7605.4 0000 0001 2336 6580 Division of Internal Medicine, Hypertension Unit, Città della Salute e della Scienza Hospital, Department of Medical Sciences, University of Turin, Turin, Italy 2 grid.7605.4 0000 0001 2336 6580 Emergency Medicine Unit, Città della Salute e della Scienza Hospital, Department of Medical Sciences, University of Turin, Turin, Italy 3 grid.7637.5 0000000417571846 Department of Internal Medicine, ASST Spedali Civili of Brescia, University of Brescia, Brescia, Italy 4 grid.5606.5 0000 0001 2151 3065 Clinic of Emergency Medicine, Department of Internal Medicine, IRCCS Ospedale Policlinico San Martino, University of Genoa, Genoa, Italy 5 grid.7563.7 0000 0001 2174 1754 Cardiothoracovascular Department, Cardiology 4 Unit, Grande Ospedale Metropolitano Niguarda Ca Granda, University of Milan-Bicocca, Milan, Italy 6 grid.411293.c 0000 0004 1754 9702 Department of Advanced Biomedical Science, Hypertension Research Center, “Federico II” University Hospital of Naples, Naples, Italy 7 Department of Medical Specialties, AUSL Toscana Centro, Internal Medicine Unit, San Marcello e San Jacopo I Hospital, Pistoia, Italy 20 2 2023 2023 46 6 15701581 21 11 2022 10 1 2023 3 2 2023 © The Author(s), under exclusive licence to The Japanese Society of Hypertension 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Hypertensive urgencies (HU) and hypertensive emergencies (HE) are challenges for the Emergency Department (ED). A prospective multicentre study is ongoing to characterize patients with acute hypertensive disorders, prevalence of subclinical hypertension-mediated organ damage (HMOD), short- and long-term prognosis; this is a preliminary report. Patients admitted to the ED with symptomatic blood pressure (BP) ≥180/110 mmHg were enrolled. They were managed by ED personnel according to their clinical presentations. Subsequently they underwent clinical evaluation and subclinical HMOD assessment at a Hypertension Centre within 72 h from enrolment. 122 patients were included in this report. Mean age was 60.7±13.9 years, 52.5% were females. 18 (14.8%) patients were diagnosed with HE, 108 (88.5%) with HU. There were no differences in gender, BMI, and cardiovascular comorbidities between groups. At ED discharge, 66.7% and 93.6% (p = 0.003) of HE and HU patients, respectively, had BP < 180/110 mmHg. After 72 h, 34.4% of patients resulted normotensive; 35.2%, 22.1%, and 8.2% had hypertension grade 1, 2, and 3, respectively. Patients with uncontrolled BP at office evaluation had higher vascular HMOD (49.1 vs. 25.9%, p = 0.045). Cardiac (60 vs. 34%, p = 0.049), renal (27.8 vs. 9.6%, p = 0.010) and cerebral (100 vs. 21%, p < 0.001) HMOD was more frequent in HE compared to HU group. HE showed greater cardiac, renal, and cerebral subclinical HMOD, compared to HU. 72-hours BP control is not associated with different HMOD, except for vascular HMOD; therefore, proper comprehensive examination after discharge from the ED could provide added value in cardiovascular risk stratification of such patients. One third of patients with acute blood pressure rise evaluated to the ED resulted normotensive at office evaluation (<72 hours after discharge). Patients with hypertensive emergency showed greater cardiac, renal, and cerebral subclinical HMOD, compared to the patients with hypertensive urgency. BP: blood pressure; HMOD: hypertension-mediated organ damage; y.o.: years old; mo.: months. One third of patients with acute blood pressure rise evaluated to the ED resulted normotensive at office evaluation (<72 hours after discharge). Patients with hypertensive emergency showed greater cardiac, renal, and cerebral subclinical HMOD, compared to the patients with hypertensive urgency. BP: blood pressure; HMOD: hypertension-mediated organ damage; y.o.: years old; mo.: months. Keywords emergency department hypertensive emergencies hypertensive urgencies short-term blood pressure control hypertension mediated organ damage issue-copyright-statement© The Japanese Society of Hypertension 2023 ==== Body pmcIntroduction Acute blood pressure (BP) disorders are a major challenge for the Emergency Department (ED). The prevalence of acute BP disorders considerably differs among studies, even depending on the definition used, but it ranges from 0.24% to 2.4% of ED admissions for hypertensive urgencies (HU) and from 0.08% to 0.76% for hypertensive emergencies (HE) [1]. These prevalences seem comparable across continents [2], although with some differences probably due to ethnic disparities, medication adherence, and insurance status [3]. Although HU do not appear to be associated with short-term adverse outcomes [4, 5], or at least have significantly lower in-hospital mortality compared to HE [6], long-term implications, such as risk of stroke and fatal or non-fatal cardiovascular events, are relevant [7–9]. Despite the significant clinical and epidemiological impact, the management of patients with acute BP disorders is still very uneven among professionals of critical areas, as pointed out by a recent Italian surveys [10, 11]. The lack of good-quality evidence makes it difficult to propose strong recommendations for clinical practice. The therapeutic management is very uneven, especially for HU. The timing of follow-up, when present, is heterogeneous and it is not clear whether a referral to a Hypertension Centre could have a prognostic role compared to standard care. In order to obtain more and more accurate information on this category of patients, we are conducting the ERIDANO prospective multicenter cohort study on behalf of the Italian Society of Hypertension (SIIA: Società Italiana dell’Ipertensione Arteriosa). The aim of the ERIDANO study is to characterize patients with acute hypertensive disorders, their prevalence of subclinical organ damage and secondary hypertension and their short- and long-term prognosis, by providing referral to a Hypertension Centre immediately after discharge from the ED, as described below. The present study is intended to be a preliminary, mainly descriptive, report of the first hundred patients enrolled, focusing on the clinical and demographic characteristics, on the management in the ED, on BP control within 72 hours of discharge, and on the prevalence of hypertension-mediated subclinical organ damage (HMOD). Methods The current enrolment has involved 6 Italian hospitals, officially starting in Turin, the main center, in January 2020. Enrollment is not to be considered consecutive, as there were many months of interruption, caused by the closure of Hypertension Centers during the four Italian epidemic wave and the commitment of internal medicine, emergency medicine, and cardiology specialists to COVID wards; in addition, the other recruiting centers became active in the first months of the year 2021 or 2022. Consecutive patients, aged 18 years and over, admitted to the ED with a symptomatic BP rise, defined as systolic BP ≥ 180 mmHg and/or diastolic BP ≥ 110 mmHg associated to at least one symptom consistent with suspected HE as defined by latest guidelines [12], were enrolled. BP measurements were performed according to the current European Society of Hypertension/European Society of Cardiology (ESH/ESC) recommendations [13], with validated automatic sphygmomanometers (e.g., Omron, M10-IT models, Matsusaka, Kyoto, Japan), with patients in the sitting position whenever possible. Three BP measurement were performed, and the mean value was used for subsequent analysis. Patients with BP rise due to traumatic causes or known neoplastic pain, or with BP rise without any associated symptoms were excluded, as were those who withheld their informed consent. Enrolled patients were managed by the emergency physicians in the ED, according to their clinical presentations, as suggested in the current European position paper [12]. After appropriate work-up, in the presence of acute organ damage (coronary ischemia, acute cardiogenic pulmonary oedema, acute ischemic or hemorrhagic stroke, hypertensive encephalopathy, acute aortic disease, acute kidney injury, relative to known creatinine values in the previous 12 months) as defined by current guidelines [12] (HE), patients were admitted to an appropriate hospital specialist setting; in the absence of acute organ damage (HU), they were discharged after a period of observation. In any case, an evaluation at an ESH Hypertension Excellence Centre was performed within 72 hours of enrolment; this visit was carried out on an outpatient-basis for discharged patients (HU), and on an inpatient-basis for HE patients, still hospitalized in the appropriate specialist setting. Subsequent therapeutic modifications, or indications for further diagnostic investigations, related to the detection of subclinical organ damage (which may be present independently of the acute organ damage), have been left to the discretion of the hypertension specialist, always guided by current guidelines [13]. The presence of subclinical HMOD does not reclassify patients into HE or HU, the definition of which is based on acute clinical damage. Figure 1 summarizes the study protocol, although data from visit 2 and visit 3 have not yet been considered in the present report.Fig. 1 Summary of Eridano Study protocol. ED emergency department, HMOD hypertension mediated organ damage Subclinical HMOD criteria Subclinical cardiac HMOD—Echocardiography Standard two-dimensional transthoracic echocardiographic (TTE) images were acquired by expert accredited staff with commercially available ultrasound machines (e.g., IE33, Phillips Medical Systems, Andover, Massachusetts, USA). Conventional parameters were assessed according to the current guidelines [14]. Left ventricular (LV) mass was estimated. Dubois’ formula was used to calculate body surface area (BSA) and LV mass values were indexed for BSA (LVMi). LV volumes and ejection fraction, and left atrial volume were assessed using Simpson’s Biplane technique from apical two and four-chamber views. LV diastolic function was estimated through the evaluation of left atrial volume, mitral inflow peak systolic velocities of early (E) and late (A) diastolic filling on pulsed-wave Doppler, color-tissue Doppler imaging of the septal and lateral mitral annulus (E’), according to current international recommendations [15]. Alterations of LV mass and geometry, increased left atrial volume, and diastolic dysfunction were considered subclinical cardiac HMOD [13, 16]. LV hypertrophy (LVH) was defined by LVMi > 115 g/m2 in men and > 95 g/m2 in women [13, 14]. Relative wall thickness (RWT) was defined as two-times inferolateral wall thickness divided by the LV diastolic diameter and was used to classify LV remodeling as either concentric (RWT > 0.42) or eccentric (RWT ≤ 0.42). Left atrial enlargement (LAe) was considered as left atrial volume indexed to BSA (LAVi) > 34 ml/m2 [14]. Subclinical vascular HMOD Arterial stiffness was quantified using carotid-femoral pulse wave velocity (PWV). Pressure waveforms at the carotid and femoral artery were obtained non-invasively by applanation tonometry with validated instruments (e.g., Sphygmocor, AtCor Medical—Sydney, Australia) [17]. Carotid artery imaging assessment was performed by experienced staff using available ultrasound machines, equipped with 4–12 MHz linear-array ultrasound transducer. The common carotid artery (CCA) intima-media thickness (IMT) was detected by validated software (e.g., Q-lab, Philips) on longitudinal bidimensional imaging. When clinically indicated patients underwent further imaging investigation. PWV > 10 m/s and CCA IMT > 0.9 mm or the presence of carotid plaques (identified by an IMT ≥1.5 mm, or by a focal increase in thickness of 0.5 mm or 50% of the surrounding carotid IMT value) were considered subclinical vascular HMOD [13, 17]. Subclinical renal HMOD Estimated glomerular filtration rate (eGFR) was assessed with Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula based on serum creatinine measured within 3 months from ED presentation [18]. Moreover, patients underwent microalbuminuria assessment. eGFR <60 ml/min/1.73 m2, urinary albumin/creatinine ratio >30 mg/g, and albuminuria > 30 mg/24 h were considered endpoints of significant renal HMOD [13, 19]. Subclinical cerebral HMOD When clinically indicated, according to ED presentations, patients underwent brain imaging, either by computed tomography or magnetic resonance imaging. The presence of white matter lesions, microinfarcts (e.g., lacunar infarctions), microbleeds, and brain atrophy identified by experienced radiologists were considered cerebral HMOD [13, 20, 21]. Statistical analysis Statistical analysis was performed by a dedicated software (R: A Language and Environment for Statistical Computing, v4.0.0 for Mac OSX, R Core Team., Vienna, Austria). Continuous variables were expressed as mean ± standard deviation. Qualitative variables were expressed as absolute values of frequency and percentage values. Normal distribution of variables was tested using the Kolmogorov-Smirnov and residual analysis tests. Differences between independent groups were evaluated using a t-test for continuous variables with normal distribution and the Mann-Whitney or Kruskal-Wallis test for continuous variables with non-normal distribution. Categorical variables were compared using the chi-square test or Fisher’s exact test, as appropriate. Statistical significance was considered for p values < 0.05. The present study was firstly approved by the Institutional Review Committee of Turin (Comitato Etico Interaziendale A.O.U. Città della Salute e della Scienza di Torino – A.O. Ordine Mauriziano, CS2/1075), as well as by the local ethics committees of each participating center. All subjects gave their written informed consent. Results A total of 113,694 patients were registered in the ED during the months of active enrollment; 1910 (1.7%) admissions were due to acute BP elevation, but only 122 (0.1% of the total) met the inclusion/exclusion criteria. Therefore, a total of 122 patients (52.5% female) with a mean age of 60.7 ± 13.9 years were enrolled until May 2022 and thus included in the present report. A total of 18 patients (14.8%) had acute organ damage at ED presentation (HE), whereas the remaining 104 (85.2%) patients were diagnosed as HU. These data correspond to a prevalence of 0.09% (104/113,694) for HU and 0.02% (18/113,694) for HE. The acute organ damages detected were heart failure (no. 7, 39%), stroke (no. 6, 33%), acute coronary syndrome (no. 2, 11%), hypertensive encephalopathy (no. 2, 11%), aortic dissection (no. 1, 6%). An eGFR < 60 ml/min/1.73 m2 was found in 5 patients at ED evaluation, but the presence of similar creatinine values in the previous 12 months (available in the informatic system), did not make them categorize as acute kidney injury. No significant difference emerged between HE and HU groups in terms of gender, BMI, cardiovascular comorbidities (Table 1). Hypertensive therapy ongoing at ED admission is listed in Table 2.Table 1 Demographic and clinical characteristics of study population Total N = 122 HE N = 18 HU N = 104 p value Male Sex [no. (%)] 58 (47.5%) 9 (50.0%) 49 (47.1%) 0.821 Age (y) 60.7 ± 13.9 66.5 ± 15.9 60.0 ± 13.5 0.134 Height (cm) 165 ± 10 166 ± 9 165 ± 11 0.644 Weight (kg) 79.6 ± 19.4 78 ± 25 79 ± 19 0.883 BMI (kg/m2) 28.9 ± 5.78 28.6 ± 7.2 28.9 ± 5.6 0.826 ED SBP (mmHg) 201 ± 20 205 ± 18 200 ± 20 0.372 ED DBP (mmHg) 113 ± 13 110 ± 14 113 ± 13 0.357 Discharge SBP (mmHg) 152 ± 21 155 ± 25 151 ± 20 0.669 Discharge DBP (mmHg) 88 ± 12 87 ± 14 88 ± 12 0.820 ED Stay (h) [IQ range] 7.2 [4.7; 12.8] 5.6 [4.7; 18.7] 7.2 [4.7; 12.2] 0.900 BP < 180/110 at ED discharge [no. (%)] 96 (78.7%) 8 (44.4%) 88 (84.6%) 0.003 Office SBP (mmHg) 147 ± 22 149 ± 22 147 ± 23 0.680 Office DBP (mmHg) 87 ± 15 88 ± 15 87 ± 16 0.746 Difference ED-Office SBP (mmHg) 54 ± 28 56 ± 34 53 ± 27 0.770 Difference ED-Office DBP (mmHg) 26 ± 17 22 ± 19 26 ± 17 0.322 Silent medical history [no. (%)] 20 (16.4%) 1 (5.6%) 19 (18.3%) 0.179 Arterial Hypertension [no. (%)] 94 (77.0%) 17 (94.4%) 77 (74.0%) 0.057 Hypertension duration (y) [IQ range] 10.0 [5.0; 18.0] 15.5 [10.0; 28.5] 10.0 [5.0; 16.0] 0.066 Diabetes [no. (%)] 24 (19.7%) 4 (22.2%) 20 (19.2%) 0.768 Dyslipidemia [no. (%)] 36 (29.5%) 8 (44.4%) 28 (26.9%) 0.132 CAD [no. (%)] 15 (12.3%) 4 (22.2%) 11 (10.6%) 0.165 Heart failure [no. (%)] 5 (4.1%) 2 (11.1%) 3 (2.9%) 0.104 Atrial fibrillation [no. (%)] 7 (5.7%) 1 (5.6%) 6 (5.8%) 0.971 Previous stroke [no. (%)] 5 (4.1%) 2 (11.1%) 3 (2.9%) 0.104 CKD [no. (%)] 8 (6.6%) 2 (11.1%) 6 (5.8%) 0.398 BMI body mass index, BP blood pressure, CAD coronary artery disease, CKD chronic kidney disease, ED emergency department, HE hypertensive emergencies, HU hypertensive urgencies, SBP systolic blood pressure, DBP diastolic blood pressure Table 2 Ongoing hypertensive therapy and medications of study population at ED admission Previous Hypertensive Therapy Total N = 122 HE N = 18 HU N = 104 p value Previous Hyp therapy [no. (%)] 85 (69.7%) 15 (83.3%) 70 (67.3%) 0.172 Nr. Previous Hyp drugs [IQ range] 1.0 [0.0; 2.0] 1.0 [1.0; 2.0] 1.0 [0.0; 2.0] 0.471 Previous Hyp drugs ≥ 3 [no. (%)] 23 (18.9%) 2 (11.1%) 21 (20.2%) 0.363 ACE-Inhibitors [no. (%)] 33 (27.0%) 8 (44.4%) 25 (24.0%) 0.072 ARB [no. (%)] 30 (24.6%) 1 (5.6%) 29 (27.9%) 0.042 CCB [no. (%)] 27 (22.1%) 6 (33.3%) 21 (20.2%) 0.215 CCB NDH [no. (%)] 0 (0.0%) 0 (0.0%) 0 (0.0%) – Beta-blockers [no. (%)] 44 (36.1%) 7 (38.9%) 37 (35.6%) 0.787 Alfa-blockers [no. (%)] 9 (7.4%) 0 (0.0%) 9 (8.7%) 0.195 Alfa2-agonist [no. (%)] 2 (1.6%) 0 (0.0%) 2 (1.9%) 0.553 MRA [no. (%)] 1 (0.8%) 0 (0.0%) 1 (1.0%) 0.676 Thiazides [no. (%)] 14 (11.5%) 2 (11.1%) 12 (11.5%) 0.958 Loop diuretics [no. (%)] 8 (6.6%) 1 (5.6%) 7 (6.7%) 0.852 Potassium sparing [no. (%)] 1 (0.8%) 0 (0.0%) 1 (1.0%) 0.676 Nitrates [no. (%)] 3 (2.5%) 1 (5.6%) 2 (1.9%) 0.358 Others hyp drugs [no. (%)] 2 (1.6%) 1 (5.6%) 1 (1.0%) 0.156 Benzodiazepines [no. (%)] 7 (5.7%) 1 (5.6%) 6 (5.8%) 0.971 ACE-Inhibitors inhibitors of angiotensin-converting enzyme, ARB angiotensin II receptor blockers, CCB calcium channel blockers, CCB-NDH non-dihydropyridine CCB, ED emergency department, HE hypertensive emergencies, HU hypertensive urgencies, Hyp hypertension, MRA mineralocorticoid receptor antagonists At ED presentation mean systolic BP was 201 ± 20 mmHg and mean diastolic BP was 113 ± 13 mmHg, without significant difference between HE and HU patients. The most common clinical presentation was headache (46.7%), followed by chest pain (23.8%), dyspnea (14.8%), and neurological symptoms (6.6%), while other non-specific symptoms were present in 68.9% of patients. A silent medical history was present in 20 patients (16.4%). Moreover, 94 patients (77%) had previously known arterial hypertension and 85 (69.7%) were on antihypertensive medical therapy, with a median number of medications of 1.0 [IQ range 0.0;2.0]; 23 patients (18.9%) were on ≥3 hypertensive drugs. Hypertensive therapy and BP control during ED stay Among patients enrolled, 61.1% and 94.2% of HE and HU group (p < 0.001) received antihypertensive therapy during ED stay (89.3% of total population), with more drugs administered in the latter group (1.0 [0.0;2.0] vs. 2.0 [1.0;2.0] in HE and HU patients, respectively, p = 0.003). A total of 25 patients (24%) of HU group received 3 or more antihypertensive medications. Intravenous antihypertensive drugs were given to 27.8% and 15.4% of patients in HE and HU group (p = 0.198). The most used class of medication was calcium channel blockers (CCB), administered to 74 patients (60.7%) (22.2% vs. 67.3% in HE and HU group, respectively, p < 0.001), followed by benzodiazepines, administered to 57 patients (46.7%) (16.7% vs. 51.9%, in HE and HU group, respectively, p = 0.006) and ACE-Inhibitors, given to 53 patients (43.4%) (16.7% vs. 48.1%, in HE and HU group, respectively, p = 0.013). The remaining classes of drugs administered during ED stay are listed in Table 3.Table 3 Hypertensive therapy and medications administered during ED stay Hypertensive therapy administered in ED Total N = 122 HE N = 18 HU N = 104 p value Hyp therapy in ED [no. (%)] 109 (89.3%) 11 (61.1%) 98 (94.2%) <0.001 Nr. Hyp drugs in ED [IQ range] 2.0 [1.0; 2.0] 1.0 [0.0; 2.0] 2.0 [1.0; 2.0] 0.003 Hyp drugs in ED ≥3 [no. (%)] 25 (20.5%) 0 (0.0%) 25 (24.0%) 0.020 IV Hyp drugs in ED [no. (%)] 21 (17.2%) 5 (27.8%) 16 (15.4%) 0.198 ACE-Inhibitors [no. (%)] 53 (43.4%) 3 (16.7%) 50 (48.1%) 0.013 ARB [no. (%)] 13 (10.7%) 2 (11.1%) 11 (10.6%) 0.946 CCB [no. (%)] 74 (60.7%) 4 (22.2%) 70 (67.3%) <0.001 CCB NDH [no. (%)] 0 (0.0%) 0 (0.0%) 0 (0.0%) – Beta-blockers [no. (%)] 26 (21.3%) 2 (11.1%) 24 (23.1%) 0.252 Alfa-blockers [no. (%)] 14 (11.5%) 0 (0.0%) 14 (13.5%) 0.098 Alfa2-agonist [no. (%)] 11 (9.0%) 1 (5.6%) 10 (9.6%) 0.579 MRA [no. (%)] 0 (0.0%) 0 (0.0%) 0 (0.0%) – Thiazides [no. (%)] 6 (4.9%) 0 (0.0%) 6 (5.8%) 0.296 Loop diuretics [no. (%)] 11 (9.0%) 2 (11.1%) 9 (8.7%) 0.737 Potassium sparing [no. (%)] 1 (0.8%) 0 (0.0%) 1 (1.0%) 0.676 Nitrates [no. (%)] 8 (6.6%) 2 (11.1%) 6 (5.8%) 0.398 Other vasodilators [no. (%)] 1 (0.8%) 0 (0.0%) 1 (1.0%) 0.676 Others hyp drugs [no. (%)] 2 (1.6%) 1 (5.6%) 1 (1.0%) 0.156 Benzodiazepines [no. (%)] 57 (46.7%) 3 (16.7%) 54 (51.9%) 0.006 Abbreviations as in Table 2 After 1 hour from ED admission, 50.0% of HE patients and 76.7% of HU patients had BP values <180/110 mmHg. At the time of ED discharge, these percentages increased to 66.7% of and 93.6%, respectively (p = 0.003) (90.6% of total population), with a median ED stay of 7.2 hours [IQ range 4.7;12.8]. At ED discharge mean systolic BP was 152 ± 21 mmHg and diastolic BP was 88 ± 12 mmHg. No drugs were significantly associated with the achievement of BP values <180/110 mmHg during ED stay (data not shown). Office blood pressure control (72 hours after ED discharge) At 72 hours visit patients had mean systolic BP of 148 ± 22 mmHg (p = 0.037, compared to BP at ED discharge) and diastolic BP of 88 ± 16 (p = 0.944). BP values <140/90 mmHg were achieved in 42 patients (34.4%) who resulted normotensive at 72 hours visit (22.2% and 36.5% of HE and HU patients, p = 0.238). 43 patients (35.2%) had grade 1 hypertension, 27 (22.1%) had grade 2 hypertension, and 10 (8.2%) had grade 3 hypertension, with no differences between HE and HU patients (p = 0.592). Patients with uncontrolled BP were more frequently males (56.3% vs. 31.0%, p = 0.008), but there were no other significant differences in terms of age, body size, and cardiovascular comorbidities. Moreover, patients with uncontrolled BP had higher mean PWV (10.1 ± 2.3 vs. 8.9 ± 2.2 m/s, p = 0.017) and higher prevalence of PWV > 10 m/s (49.1 vs. 25.9%, p = 0.045), even after adjusting for heart rate and mean BP (data not shown). Hypertensive therapy prescribed at 72 hours visit is depicted in Table 4.Table 4 Hypertensive therapy and medications prescribed at 72 hours visit Hypertensive therapy prescribed at 72 h visit Total N = 122 HE N = 18 HU N = 104 p value Hyp therapy at 72 h [no. (%)] 105 (86.0%) 10 (55.6%) 95 (91.3%) <0.001 Hyp drugs at 72 h (no) [IQ range] 3.0 [2.0; 4.0] 2.0 [0.0; 2.75] 3.0 [2.0; 4.0] 0.023 Hyp drugs at 72 h ≥ 3 [no. (%)] 65 (53.3%) 5 (27.8%) 60 (57.7%) 0.019 ACE-Inhibitors [no. (%)] 30 (24.6%) 5 (27.8%) 25 (24.0%) 0.734 ARB [no. (%)] 56 (45.9%) 4 (22.2%) 52 (50.0%) 0.029 CCB [no. (%)] 85 (69.7%) 7 (38.9%) 78 (75%) 0.002 CCB NDH [no. (%)] 15 (12.3%) 0 (0.0%) 15 (14.4%) 0.085 Beta-blockers [no. (%)] 39 (32.0%) 6 (33.3%) 33 (31.7%) 0.893 Alfa-blockers [no. (%)] 30 (24.6%) 1 (5.6%) 29 (27.9%) 0.042 Alfa2-agonist [no. (%)] 2 (1.6%) 0 (0.0%) 2 (1.9%) 0.553 MRA [no. (%)] 8 (6.6%) 2 (11.1%) 6 (5.8%) 0.398 Thiazides [no. (%)] 25 (20.5%) 2 (11.1%) 23 (22.1%) 0.286 Loop diuretics [no. (%)] 9 (7.4%) 3 (16.7%) 6 (5.8%) 0.102 Potassium sparing [no. (%)] 2 (1.6%) 0 (0.0%) 2 (1.9%) 0.553 Nitrates [no. (%)] 10 (8.2%) 1 (5.6%) 9 (8.7%) 0.658 Others hyp drugs [no. (%)] 1 (0.8%) 1 (5.6%) 0 (0.0%) 0.016 Benzodiazepines [no. (%)] 2 (1.6%) 1 (5.6%) 1 (1.0%) 0.156 Abbreviations as in Table 2 Hypertension-mediated subclinical organ damage (HMOD) at 72 hours visit LVH was present in 41 patients (33.6% of total population; 50% and 30.8% of HE and HU patients, respectively, p = 0.0.54). HE group showed higher LVMi compared to HU group (110.9 ± 36.0 vs. 93.0 ± 26.4 g/m2, p = 0.023). LAe was detected in 26 patients (21.3%); no difference in LAe prevalence was found between HE and HU group (22.2% vs. 21.2%, p = 0.836), but the former group had significant higher LAVi (37.8 ± 17.4 vs. 28.2 ± 10.0, p = 0.014). Systolic and diastolic function was similar between the two groups. Subclinical vascular HMOD was assessed in 91 patients and was detected in 49 patients (53.9%). Of the 82 patients whose arterial stiffness was tested, 34 (41.5%) had PWV > 10 m/s, and of the 58 patients tested with carotid ultrasound, 25 (43.1%) had CCA IMT > 0.9 mm or carotid plaques. Indices of subclinical vascular HMOD were proved to be comparable between the two groups (Table 5).Table 5 Subclinical hypertension mediated organ damage characteristics of study population Total N = 122 HE N = 18 HU N = 104 p value LVMi (g/m2) 95.5 ± 28.4 110.9 ± 36.0 93.0 ± 26.4 0.023 LVH [no. (%)] 41 (33.6%) 9 (50.0%) 32 (30.8%) 0.054 EF (%) 61.3 ± 7.9 57.9 ± 5.0 61.9 ± 7.0 0.067 LAVi (ml/m2) 29.2 ± 11.2 37.8 ± 17.4 28.2 ± 10.0 0.014 LAe [no. (%)] 26 (21.3%) 4 (22.2%) 22 (21.2%) 0.836 Ascending aorta (mm) 34.4 ± 4.9 36.2 ± 5.0 34.1 ± 4.8 0.171 E/E’ ratio 9.28 ± 4.57 9.91 ± 3.34 9.21 ± 4.71 0.634 E/E’ ratio > 14 [no. (%)] 12 (9.8%) 3 (16.7%) 9 (8.7%) 0.081 TR max vel (m/s) 2.32 ± 0.43 2.51 ± 0.33 2.31 ± 0.44 0.380 PWV (m/s)a 9.71 ± 2.30 9.83 ± 1.54 9.68 ± 2.41 0.847 PWV > 10 m/s [no. (%)]a 34 (39.5%)a 4 (33.3%)a 30 (40.5%)a 0.536 Abnormal carotid US [no. (%)]b 25 (43.1%)b 4 (66.7%)b 21 (40.4%)b 0.218 Vascular HMOD [no. (%)]c 49 (53.8%)c 7 (46.7%)c 42 (55.3%)c 0.542 Renal HMOD [no. (%)] 15 (12.3%) 5 (27.8%) 10 (9.6%) 0.010 Cerebral HMOD [no. (%)]d 16 (34.8%)d 8 (100%)d 8 (21.1%)d <0.001 E/E’ ratio mean transmitral inflow early wave on pulsed-wave Doppler to mitral annulus (lateral/septal) early wave on tissue-doppler imaging ratio, EF ejection fraction, HMOD hypertension mediated organ damage, LAe left atrial enlargement, LAVi left atrial volume indexed for body surface area, LVH left ventricular hypertrophy, LVMi left ventricular mass indexed for body surface area, PWV pulse wave velocity aData available for 86 patients (12 patients among HE, 74 patients among HU) bData available for 58 patients (6 patients among HE, 52 patients among HU) cData available for 91 patients (15 patients among HE, 76 patients among HU) dData available for 46 patients (8 patients among HE, 38 patients among HU) Subclinical renal HMOD was observed in 15 patients (12.3%). HE patients had higher prevalence of renal damage than HU patients (27.8% vs. 9.6%, p = 0.010). Brain damage was detected in 16 patients (34.8% of 46 patients who underwent brain imaging during ED evaluation), and it was detected in all HE patients who underwent brain imaging (100% vs. 21.1%, p < 0.001). In summary, subclinical HMOD was detected in 82 patients (67.2% of total population), 100% of HE patients and 61.5% of HU patients (p = 0.001). Patients with detected subclinical HMOD were older than patients without HMOD (64.4 ± 13 vs. 53.3 ± 12 years, p < 0.001), and had more likely history of diabetes (p < 0.001), dyslipidemia (p = 0.042), coronary artery disease (p = 0.021), and chronic kidney disease (p = 0.041). Patients with detected subclinical HMOD were also taking higher median number of hypertensive drugs at ED admission (1.0 [0.0; 1.0] vs. 1.0 [0.0; 2.0], p = 0.004), and had higher mean systolic BP values at ED admission (204 ± 18 vs. 194 ± 20 mmHg, p = 0.007) and at 72 h visit (150 ± 23 vs. 140 ± 19 mmHg, p = 0.016). Discussion This report described around the first hundred patients with acute hypertensive disorders enrolled within the Italian multicenter prospective study called Eridano. This study has an ambitious prognostic aim, but, at present, only descriptive data from the first visits have been presented, specifically the ED enrolment and the office evaluation within 72 hours of ED discharge. Acute hypertensive disorders are serious medical conditions, with a combined prevalence of 1.2% of total admission in the ED, in the most recent meta-analysis on the topic [1]. In the present prospective study, it is difficult to estimate the true prevalence of these conditions, considering the changes in the ED admissions dictated by the COVID-19 pandemic [22, 23]. Our data correspond to a prevalence of 0.09% for HU and 0.02% for HE; much lower prevalences compared to literature data, which could partly account for the truth regarding the lower number of ED admissions during the pandemic, but could also be the result of underestimation of data due to enrollment issue for logistical difficulties that have affected all italian hospitals in recent years. In fact, the overall prevalence of admission for acute BP disorders (1.7%), not considering the inclusion/exclusion criteria of the current study, is similar to the literature data. Also, this large difference could be dictated by the high attention to the presence of symptoms at ED presentation. Most data regarding acute BP disorders consider both symptomatic and asymptomatic patients, while we focused on patients having symptoms consistent with possible acute hypertensive organ damage. This could have led to a low proportion of patients actually included in the study, among the overall patients being registered at ED presentation as having acute BP disorders. The ratio between HE and HU is similar to those of previous studies [24–30]. Some differences are at least in part explained by the different HE/HU definitions, in terms of BP cut-off or diagnostic coding; in a large retrospective study, the prevalence of HE in the United States between 2006 and 2013 was lower, probably due to the strict definition, based on acute BP elevation together with a diagnosis of acute organ damage based on the ICD-9 code [2]. In a recent review, the prevalence of HE in the Asian population ranges from 0.1 to 1.5% [31]. Our population is younger than the previous Italian multicenter study, whose enrolment was held in 2009, by about 10 years [27], but with similar age of an Asian study from the most recent recruitment [32]. Although we need to increase the sample size to confirm these data, no differences in age, sex and cardiovascular comorbidities are currently present between HE and HU. This seems to disagree with previous findings, in which HE was associated with male sex [24, 27], older age, and comorbidities [29]. Pharmacological management in ED confirms for the umpteenth time the great inconsistency among professionals concerning the treatment of acute BP disorders, as well pointed out by the GEAR project [10]. Frequently, antihypertensive drugs are used with the goal of acutely reducing BP in HU, while there is no benefits to support this practice [4, 33]. In contrast, there are data on the possible damage from rapid BP reduction in patients without organ damage [34]. Although mostly based on expert opinion, there are official recommendations on the treatment of HE [12]; moreover, a reasoned pharmacological approach has recently been proposed, starting from the pathophysiology of HE [35, 36]. Indeed, the major problem seems to be represented by patients with HU, where the greatest discrepancies in treatment approach are found, including the use of intravenous drugs, absolutely not recommended in this context. The current European position paper [12] suggests that HU should be treated in the same way as asymptomatic uncontrolled hypertension, by modifying home therapy without claiming rapid BP reduction in the emergency room. In these patients, oral administration of antihypertensive drugs, aimed at gradual BP reduction over the following days, is the best approach [37–39]. In our cohort, CCBs were the most widely used class; in particular, amlodipine, the most available drug in the class in Italian ED, was used in 99% of cases (73 out of 74 patients); nifedipine was used in only one case. These data are fortunately a marked improvement from the frequent use shown in the survey cited above [10], where 22% of participants (and 23% of those working in the ED) were inclined to use sublingual nifedipine to reduce BP, although its use has been discouraged for years because of possible deleterious effects [40]. Long-acting CCBs are also encouraged in this context because they do not interfere with diagnostics, and consequently allow the search for secondary causes of hypertension when indicated [35]. Captopril remains by far the most widely used drug within the class of ACE inhibitors (31 out of 53 patients treated with this class in our cohort). Compared to nifedipine, captopril has been shown to be equally effective in terms of BP reduction, but with fewer side effects [41]; however, considerations must be taken even with this drug due to the possible sudden hypotension [42]. A special consideration should be given to benzodiazepines, class not officially suggested but widely used in clinical practice, as evidenced by previous studies [10, 24, 29]. Administered in almost half of the cases in our cohort, benzodiazepines are definitely recommended medication in adrenergic hyperactivity BP disorders, such as cocaine abuse [38, 43], but their use outside this context would merit more in-depth studies. Patients with HU treated with benzodiazepines demonstrated greater reductions in systolic BP values, than patients not treated with anxiolytic therapy [44]. In a randomized clinical trial, diazepam demonstrated the same pressor effect as nifedipine and propranolol [45]; in another trial, the same pressor effect of captopril [46]. In the present report, 70% of prescribers considered administering benzodiazepines to reduce an obvious anxiety symptomatology associated with the BP rise, while 30% of prescribers used benzodiazepines for an expected stand-alone antihypertensive effect, independent of anxiety. The marked difference in the proportion of benzodiazepines administration between ED and ambulatory visit (52 vs. 1%) is probably due to the need to counter the anxiety effect on BP during symptomatic ED presentation, not so markedly present at the office evaluation. Likely, patients with acute BP disorders, especially those without acute clinical organ damage, suffer from an overlap of true BP elevation and anxiety effect, that leads to very high BP values. This effect is also probably enhanced by the presence of symptoms. During office evaluation, once the symptoms and the fear for life-threatening situation are over, BP values are less influenced by anxiety, and benzodiazepines prescription is not required anymore. The fact that not all patients with HE were treated in our cohort is surprising, but this data could be distorted by rapid admission to the intensive or semi-intensive units with treatment initiated outside the ED (indeed, the median ED stay of 7.2 hours is mainly due to HU, in a situation of Italian ED currently characterized by overcrowding and boarding problems). Furthermore, in ischemic strokes (no. 5 in our cohort), the cut-off for starting acute antihypertensive treatment is higher than that of HE diagnosis. To our knowledge, our study is currently the only one that prospectively and systematically assesses short-term (72 hours) BP control in office setting after ED discharge, except for a small study on 21 hypertensive patients in which 24h-ABPM immediately after discharge from the ED [47]. Approximately 90% of patients in our study were discharged from the ED with BP < 180/110 mmHg, thus no longer meeting the criteria for HU, for those without organ damage; a similar rate has been described in recent studies [48, 49]. In about one-third of the cases, normal office BP was present at 72 hours after ED discharge; similar outcome than that reported, of about 20% at 2 weeks after discharge, in a retrospective study conducted in the Thai population [49], but very different from the previously cited Israeli report in which 17 out of 21 patients remained with a SBP > 180 mmHg 24 hours after ED discharge [47]. The median number of hypertensive drugs prescribed increased from 1.0 [IQR 0.0; 2.0] before ED admission, to 2.0 [IQR 1.0; 2.0] during ED stay, and eventually to 3.0 [IQR 2.0; 4.0] at 72 h visit. These data confirm both the high BP variability in this population and the need for aggressive treatment. Finally, we presented some data on subclinical HMOD: to our knowledge this is the first study to assess subclinical HMOD in HE and HU patients immediately after ED discharge. In general, HE patients had worse subclinical HMOD profile than HU patients, particularly cardiac, renal, and cerebral HMOD, while vascular HMOD was comparable. At 72 h visit, patients with uncontrolled BP had worse PWV, suggesting a possible role of aortic stiffness in impeding proper BP control, or possibly grater vascular damage in patients with short-term uncontrolled BP. A recent study showed that HU patients had subclinical HMOD profile midway between patients with asymptomatic grade 3 hypertension and patients with various grade hypertension, matched for office BP [50]. The higher prevalence of subclinical HMOD in HE patients found in the present study underlines that HE patients have worse baseline CV risk profile than HU patients, leading to more severe manifestations of acute BP rise. Moreover, this difference in subclinical HMOD was not observed when comparing patients with controlled and uncontrolled BP at 72 h visit, somehow indicating that some patients could represent a special high-risk population, irrespectively of acute and short-term BP control. Ongoing follow-up is needed to better define this aspect. Study limitations and future perspectives It should be stressed first of all that the prevalence data are the result of an estimation calculated on the basis of the months of active enrollment in the various centers and the average visits to the EDs; therefore, these are numbers to be taken with caution because they could represent an underestimation of reality even if a reduction in prevalences could have been expected during COVID-19 pandemic. As specified, complete follow-up is needed to add prognostic value to the subclinical organ damage in this category of patients. It may be interesting to assess whether early in-depth evaluation at specialized hypertension centers could improve prognosis compared to standard management especially for the category of patients without acute clinical damage. The present study has a purely descriptive nature, impaired by the small total number and the numerical discrepancy between the two groups analyzed (HE and HU); this must make comparisons interpreted with caution. At the same time, it has the advantages of describing short-term BP control and the investigation of subclinical HMOD immediately after discharge from the ED. Ad hoc designed studies are needed to suggest appropriate management of HU in the ED, as well as targeted education to ED physicians by hypertension experts. Finally, in addition to cardiovascular drugs, benzodiazepines may be powerful weapons, already long used in clinical practice, to treat these disorders. It would be intriguing to evaluate their real hypotensive potential, perhaps considering the psychological characteristics of each patient. The use of benzodiazepines in these cases may be beneficial for both hypotensive and stress releasing effects, while significant harm is unlikely to result, being careful not to overestimate anxiety/stress effect over BP. Anyway, at present, pending stronger evidence, the results presented do not allow benzodiazepines to be recommended in acute hypertensive disorders, except in cases of associated overt anxiety, which is itself an indication for such therapy. Conclusions Acute BP disorders are a major challenge for the ED. The lack of good-quality evidence makes it difficult to propose strong recommendations for clinical practice. In this first report about the ongoing prospective Italian multicenter study ERIDANO, we showed that great inconsistency is present in acute BP disorder management. Up to one third of patients resulted normotensive after 72 h after ED discharge. HE patients showed greater cardiac, renal, and cerebral subclinical HMOD, compared to HU patients. 72 h BP control is not associated with different subclinical HMOD, except for vascular HMOD; therefore, proper comprehensive examination after discharge from the ED could provide added value in cardiovascular risk stratification of such patients. Acknowledgements We are grateful to staff physicians and fellows of the Emergency departments and Hypertensive centers for their work. We also thank Michela Algeri, Arianna Ardito, Giordano Bianchi, Carmine De Luca, Saverio Fabbri, Claudio Pascale, Alessandra Piazza, Giuliano Pinna, Giovanni Saccà, Nicole Saxinger, and Maria Tizzani for essential collaboration and useful discussion. Compliance with ethical standards Conflict of interest The authors declare no competing interests. Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. These authors contributed equally: Fabrizio Vallelonga, Marco Cesareo. ==== Refs References 1. Astarita A Covella M Vallelonga F Cesareo M Totaro S Ventre L Hypertensive emergencies and urgencies in emergency departments: a systematic review and meta-analysis J Hypertens 2020 38 1203 10 10.1097/HJH.0000000000002372 32510905 2. Janke AT, McNaughton CD, Brody AM, Welch RD, Levy PD. Trends in the incidence of hypertensive emergencies in us emergency departments from 2006 to 2013. J Am Heart Assoc. 2016;5. 10.1161/JAHA.116.004511 3. Van Den Born BJH Koopmans RP Groeneveld JO Van Montfrans GA Ethnic disparities in the incidence, presentation and complications of malignant hypertension J Hypertens 2006 24 2299 304 10.1097/01.hjh.0000249710.21146.38 17053554 4. Levy PD Mahn JJ Miller J Shelby A Brody A Davidson R Blood pressure treatment and outcomes in hypertensive patients without acute target organ damage: a retrospective cohort Am J Emerg Med 2015 33 1219 24 10.1016/j.ajem.2015.05.036 26087706 5. Patel KK Young L Howell EH Hu B Rutecki G Thomas G Characteristics and outcomes of patients presenting with hypertensive urgency in the office setting JAMA Intern Med 2016 176 981 8 10.1001/jamainternmed.2016.1509 27294333 6. Guiga H Decroux C Michelet P Loundou A Cornand D Silhol F Hospital and out-of-hospital mortality in 670 hypertensive emergencies and urgencies J Clin Hypertens 2017 19 1137 42 10.1111/jch.13083 7. Rothwell PM Howard SC Dolan E O’Brien E Dobson JE Dahlöf B Prognostic significance of visit-to-visit variability, maximum systolic blood pressure, and episodic hypertension Lancet 2010 375 895 905 10.1016/S0140-6736(10)60308-X 20226988 8. Vlcek M Bur A Woisetschläger C Herkner H Laggner AN Hirschl MM Association between hypertensive urgencies and subsequent cardiovascular events in patients with hypertension J Hypertens 2008 26 657 62 10.1097/HJH.0b013e3282f4e8b6 18327073 9. Paini A Tarozzi L Bertacchini F Aggiusti C Rosei CA De Ciuceis C Cardiovascular prognosis in patients admitted to an emergency department with hypertensive emergencies and urgencies J Hypertens 2021 39 2514 20 10.1097/HJH.0000000000002961 34420015 10. Saladini F Mancusi C Bertacchini F Spannella F Maloberti A Giavarini A Diagnosis and treatment of hypertensive emergencies and urgencies among Italian emergency and intensive care departments. Results from an Italian survey: Progetto GEAR (Gestione dell’Emergenza e urgenza in ARea critica) Eur J Intern Med 2020 71 50 56 10.1016/j.ejim.2019.10.004 31690479 11. Saladini F, Mancusi C, Bertacchini F, Spannella F, Maloberti A, Giavarini A, et al. Differences in Diagnosis and Management of Hypertensive Urgencies and Emergencies According to Italian Doctors from Different Departments Who Deal With Acute Increase in Blood Pressure-Data from Gear (Gestione Dell’emergenza e Urgenza in ARea Critica) St. J Clin Med. 2022;11. 10.3390/jcm11112986 12. Van Den Born BJH Lip GYH Brguljan-Hitij J Cremer A Segura J Morales E ESC Council on hypertension position document on the management of hypertensive emergencies Eur Hear J Cardiovasc Pharmacother 2019 5 37 46 10.1093/ehjcvp/pvy032 13. Williams B Mancia G Spiering W Rosei EA Azizi M Burnier M 2018 ESC/ESH Guidelines for themanagement of arterial hypertension Eur Heart J 2018 39 3021 104 10.1093/eurheartj/ehy339 30165516 14. Lang RM Badano LP Victor MA Afilalo J Armstrong A Ernande L Recommendations for cardiac chamber quantification by echocardiography in adults: An update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging J Am Soc Echocardiogr 2015 28 1 39.e14 10.1016/j.echo.2014.10.003 25559473 15. Nagueh SF Smiseth OA Appleton CP Byrd BF Dokainish H Edvardsen T Recommendations for the Evaluation of Left Ventricular Diastolic Function by Echocardiography: An Update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging J Am Soc Echocardiogr 2016 29 277 314 10.1016/j.echo.2016.01.011 27037982 16. Marwick TH Gillebert TC Aurigemma G Chirinos J Derumeaux G Galderisi M Recommendations on the use of echocardiography in adult hypertension: A report from the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE) Eur Heart J Cardiovasc Imaging 2015 16 577 605 10.1093/ehjci/jev076 25995329 17. Van Bortel LM Laurent S Boutouyrie P Chowienczyk P Cruickshank JK De Backer T Expert consensus document on the measurement of aortic stiffness in daily practice using carotid-femoral pulse wave velocity J Hypertens 2012 30 445 8 10.1097/HJH.0b013e32834fa8b0 22278144 18. Levey AS Stevens LA Schmid CH Zhang YL Castro AF 3rd Feldman HI A new equation to estimate glomerular filtration rate Ann Intern Med 2009 150 604 12 10.7326/0003-4819-150-9-200905050-00006 19414839 19. Cheung AK Chang TI Cushman WC Furth SL Hou FF Ix JH Executive summary of the KDIGO 2021 Clinical Practice Guideline for the Management of Blood Pressure in Chronic Kidney Disease Kidney Int 2021 99 559 69 10.1016/j.kint.2020.10.026 33637203 20. Longstreth WTJ Manolio TA Arnold A Burke GL Bryan N Jungreis CA Clinical correlates of white matter findings on cranial magnetic resonance imaging of 3301 elderly people. The Cardiovascular Health Study Stroke 1996 27 1274 82 10.1161/01.str.27.8.1274 8711786 21. Boulestreau R Lucas L Cremer A Debeugny S Rubin S Gaudissard J Neurologically asymptomatic patients frequently present cerebral injuries during malignant hypertension: a MRI study J Hypertens 2021 39 2463 9 10.1097/HJH.0000000000002950 34343146 22. Reschen ME Bowen J Novak A Giles M Singh S Lasserson D Impact of the COVID-19 pandemic on emergency department attendances and acute medical admissions BMC Emerg Med 2021 21 143 10.1186/s12873-021-00529-w 34800973 23. Leontsinis I Papademetriou V Chrysohoou C Kariori M Dalakouras I Tolis P Hypertensive urgencies during the first wave of the COVID-19 pandemic in a tertiary hospital setting: a U-shaped alarming curve Arch Med Sci 2022 18 982 90 10.5114/aoms/141243 35832718 24. Salvetti M Paini A Colonetti E Tarozzi L Bertacchini F Aggiusti C Hypertensive emergencies and urgencies: A single-centre experience in Northern Italy 2008-2015 J Hypertens 2020 38 52 58 10.1097/HJH.0000000000002213 31415308 25. Martin JFV, Higashiama E, Garcia E, Luizon MR, Cipullo JP. Hypertensive crisis profile. Prevalence and clinical presentation. Arq Bras Cardiol. 2004;83. 26. Vilela-Martin JF Vaz-De-Melo RO Kuniyoshi CH Abdo ANR Yugar-Toledo JC Hypertensive crisis: Clinical-epidemiological profile Hypertens Res 2011 34 367 71 10.1038/hr.2010.245 21160483 27. Pinna G, Pascale C, Fornengo P, Arras S, Piras C, Panzarasa P, et al. Hospital admissions for hypertensive crisis in the emergency departments: A large multicenter Italian study. PLoS One. 2014;9. 10.1371/journal.pone.0093542 28. Zampaglione B Pascale C Marchisio M Cavallo-Perin P Hypertensive urgencies and emergencies: Prevalence and clinical presentation Hypertension 1996 27 144 7 10.1161/01.HYP.27.1.144 8591878 29. Vallelonga F Carbone F Benedetto F Airale L Totaro S Leone D Accuracy of a Symptom-Based Approach to Identify Hypertensive Emergencies in the Emergency Department J Clin Med 2020 9 2201 10.3390/jcm9072201 32664670 30. Fragoulis C Dimitriadis K Siafi E Iliakis P Kasiakogias A Kalos T Profile and management of hypertensive urgencies and emergencies in the emergency cardiology department of a tertiary hospital: a 12-month registry Eur J Prev Cardiol 2022 29 194 201 10.1093/eurjpc/zwab159 34718521 31. Kotruchin P Tangpaisarn T Mitsungnern T Sukonthasarn A Hoshide S Turana Y Hypertensive emergencies in Asia: A brief review J Clin Hypertens 2022 24 1226 35 10.1111/jch.14547 32. Shin J-H, Kim BS, Lyu M, Kim H-J, Lee JH, Park J-K, et al. Clinical Characteristics and Predictors of All-Cause Mortality in Patients with Hypertensive Urgency at an Emergency Department. J Clin Med. 2021;10. 10.3390/jcm10194314 33. Jolly H, Freel EM, Isles C Management of hypertensive emergencies and urgencies: narrative review. Postgrad Med J (e-pub ahead of print October 2021. 10.1136/postgradmedj-2021-140899). 34. Yanturali S Akay S Ayrik C Cevik AA Adverse events associated with aggressive treatment of increased blood pressure Int J Clin Pr 2004 58 517 9 10.1111/j.1368-5031.2004.00171.x 35. Rossi GP Rossitto G Maifredini C Barchitta A Bettella A Cerruti L Modern Management of Hypertensive Emergencies High blood Press Cardiovasc Prev J Ital Soc Hypertens 2022 29 33 40 10.1007/s40292-021-00487-1 36. Gosse P Boulestreau R Brockers C Puel C Rubin S Cremer A The pharmacological management of malignant hypertension J Hypertens 2020 38 2325 30 10.1097/HJH.0000000000002547 32649635 37. Muiesan ML Salvetti M Amadoro V di Somma S Perlini S Semplicini A An update on hypertensive emergencies and urgencies J Cardiovasc Med 2015 16 372 82 10.2459/JCM.0000000000000223 38. Salvetti M Paini A Bertacchini F Stassaldi D Aggiusti C Agabiti Rosei C Acute blood pressure elevation: Therapeutic approach Pharm Res 2018 130 180 90 10.1016/j.phrs.2018.02.026 39. Miller J McNaughton C Joyce K Binz S Levy P Hypertension Management in Emergency Departments Am J Hypertens 2020 33 927 34 10.1093/ajh/hpaa068 32307541 40. Grossman E Messerli FH Grodzicki T Kowey P Should a moratorium be placed on sublingual nifedipine capsules given for hypertensive emergencies and pseudoemergencies? JAMA 1996 276 1328 31 10.1001/jama.1996.03540160050032 8861992 41. Kaya A Tatlisu MA Kaplan Kaya T Yildirimturk O Gungor B Karatas B Sublingual vs. Oral Captopril in Hypertensive Crisis J Emerg Med 2016 50 108 15 10.1016/j.jemermed.2015.07.017 26409670 42. Maloberti A Cassano G Capsoni N Gheda S Magni G Azin GM Therapeutic Approach to Hypertension Urgencies and Emergencies in the Emergency Room High blood Press Cardiovasc Prev J Ital Soc Hypertens 2018 25 177 89 10.1007/s40292-018-0261-4 43. Hollander JE Cocaine intoxication and hypertension Ann Emerg Med 2008 51 S18 20 10.1016/j.annemergmed.2007.11.008 18191302 44. Paštrović F Okštajner PK Vodanović M Raos D Jug J Lovrić Benčić M The Role of Anxiolytics in Hypertensive Urgency Management Psychiatr Danub 2020 32 593 6 33212468 45. Mansur A de P Ramires JA Avakian SD de Paula RS Pileggi F [Comparison of the effects of diazepam, nifedipine, propranolol and a combination of nifedipine and propranolol, by sublingual administration, in patients with hypertensive crisis] Arq Bras Cardiol 1991 57 313 7 1824527 46. Grossman E Nadler M Sharabi Y Thaler M Shachar A Shamiss A Antianxiety treatment in patients with excessive hypertension Am J Hypertens 2005 18 1174 7 10.1016/j.amjhyper.2005.03.728 16182105 47. Rock W Zbidat K Schwartz N Elias M Minuhin I Shapira R Pattern of Blood Pressure Response in Patients With Severe Asymptomatic Hypertension Treated in the Emergency Department J Clin Hypertens (Greenwich) 2016 18 796 800 10.1111/jch.12765 26719049 48. Lin Y-T Liu Y-H Hsiao Y-L Chiang H-Y Chen P-S Chang S-N Pharmacological blood pressure control and outcomes in patients with hypertensive crisis discharged from the emergency department PLoS One 2021 16 e0251311. 10.1371/journal.pone.0251311 34403407 49. Kotruchin P Mitsungnern T Ruangsaisong R Imoun S Pongchaiyakul C Hypertensive Urgency Treatment and Outcomes in a Northeast Thai Population: The Results from the Hypertension Registry Program High Blood Press Cardiovasc Prev 2018 25 309 15 10.1007/s40292-018-0272-1 30051205 50. Vallelonga F Cesareo M Menon L Airale L Leone D Astarita A Cardiovascular Hypertension-Mediated Organ Damage in Hypertensive Urgencies and Hypertensive Outpatients Front Cardiovasc Med 2022 9 889554. 10.3389/fcvm.2022.889554 35651902
PMC009xxxxxx/PMC9944799.txt	==== Front J Gen Philos Sci J Gen Philos Sci Journal for General Philosophy of Science 0925-4560 1572-8587 Springer Netherlands Dordrecht 36843654 9633 10.1007/s10838-022-09633-2 Article Science, Values, and the New Demarcation Problem http://orcid.org/0000-0002-5139-9555 Resnik David B. [email protected] 1 Elliott Kevin C. 2 1 grid.280664.e 0000 0001 2110 5790 National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC USA 2 grid.17088.36 0000 0001 2150 1785 Philosophy and Sociology of Science, Department of Fisheries and Wildlife and Department of Philosophy, Michigan State University, East Lansing, MI USA 22 2 2023 2023 54 2 259286 23 11 2022 © This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2023 This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. In recent years, many philosophers of science have rejected the “value-free ideal” for science, arguing that non-epistemic values have a legitimate role to play in scientific inquiry. However, this philosophical position raises the question of how to distinguish between legitimate and illegitimate influences of values in science. In this paper, we argue that those seeking to address this “new” demarcation problem can benefit by drawing lessons from the “old” demarcation problem, in which philosophers tried to find a way of distinguishing between science and non-science. Many of those who worked on this problem ultimately found that efforts to provide necessary and sufficient conditions for defining science failed, and most concluded that the best solution to the problem was to characterize scientific hypotheses, theories, and research programs in terms of some common norms. We suggest that those seeking to distinguish between legitimate and illegitimate value influences on science would do well to adopt a similar approach. Rather than attempting to establish necessary and sufficient conditions for identifying appropriate value influences, it will be more fruitful to evaluate scientific activities based on their adherence to a set of epistemic and ethical norms that can be implemented in scientific practice by means of rules, conventions, policies, and procedures. Keywords Science Values Demarcation Objectivity Ethics National Institute of Environmental Health Sciencesissue-copyright-statement© Springer Nature B.V. 2023 ==== Body pmcIntroduction During the twentieth century, most philosophers of science subscribed to the notion that science should be free from the influence of non-epistemic, external values, such as moral, social, economic, or political values (Douglas 2009). Proponents of this view recognized that social and economic conditions, such as the availability of research funding and ethical constraints on the conduct of research, can impact scientific practice, but they maintained that the values that create these conditions should not be allowed to influence judgments and decisions which are internal to the epistemology and methodology of science. Science itself should remain as free as is humanly possible from external values (Douglas 2009).1 Although some philosophers (e.g., Haack 2004; Betz 2013; Hudson 2016) still accept some version of the value-free ideal for science, others reject the value-free ideal and argue that scientists should incorporate external values into judgments and decisions at various stages of inquiry (Douglas 2009; Steel 2010; Kourany 2010; Elliott 2017; Brown 2020). This shift in philosophical thinking about the relationship between science and external values is due largely to penetrating critiques of the value-free ideal developed by philosophers, historians, and sociologists of science who argued that external values appropriately affect judgments and decisions related to such tasks as hypothesis and concept formation, theory construction, and hypothesis or theory acceptance.2 Rejecting the value-free ideal creates a new problem, however, namely, how can one distinguish between legitimate and illegitimate value influences (Holman and Wilholt 2022; Resnik and Elliott 2019)? Resolution of this issue has important implications for science and society, since illegitimate value influences can undermine the integrity, reliability, and trustworthiness of science (Resnik 2007; 2009; Goldenberg 2021). Well-known examples of the corrupting influence of values on science include fraudulent, biased, misleading, or irreproducible studies conducted by pharmaceutical, tobacco, food, and energy companies to promote their economic interests (Resnik 2007; 2009; Michaels 2008; McGarity and Wagner 2008; Oreskes and Conway 2010; Holman and Elliott 2018; Richie 2020). Value corruption is not limited to private industry, however, since academic researchers sometimes fabricate, falsify, or deceptively manipulate data to promote their careers or financial interests, and researchers funded by environmental, political, or consumer interest groups sometimes manipulate or distort science for the sake of “worthy” causes, such as protecting public health or the environment (Wagner and Steinzor 2006; McGarity and Wagner 2008; Resnik 2015; Ritchie 2020; Saphier 2021; Shamoo and Resnik 2022). Holman and Wilholt (2022) have called the issue of how to distinguish between legitimate and illegitimate external value influences on science the “new” demarcation problem. While this is indeed a new problem for the philosophy of science, it is not entirely clear how it relates to the original demarcation problem as initially formulated by Karl Popper. Something both problems have in common is a concern with the practical applications of theories and hypotheses that are regarded as scientific. One reason why Popper thought it was important to distinguish between science and pseudoscience was to prevent theories he regarded as pseudoscientific from having detrimental impacts on society (Popper 1959; 1963; Magee 1985). Philosophers who are working on the new demarcation problem also want to prevent research from having adverse impacts on society, but they are more concerned with the impacts of biased, misleading, or fraudulent science on society than with pseudoscience’s impacts (Douglas 2009; Resnik and Elliott 2019; Koskinen and Rolin 2022). The new demarcation problem is much more complex and multifaceted than the original problem because distinguishing between legitimate and illegitimate value influences requires one to provide an account of the difference between good and bad science, which is no simple task, since there are many ways that science can go wrong (Ritchie 2020; Boudry 2021). A study might be recognized as scientific even though it has been corrupted by external values in various ways. For example, a study sponsored by a pharmaceutical company which claims that its new hypertension drug is superior to competing medications might fail to produce good evidence for this conclusion due to insufficient sample size; lack of control groups, blinding, or randomization; poor recordkeeping; or biased data analysis or interpretation (Gallin et al. 2018). While the key question for the original demarcation problem was “Is this theory or hypothesis scientific?”, the key question for the new problem is “Has this experiment, clinical trial, survey, longitudinal study, meta-analysis, systematic review, or other research product been inappropriately influenced by external values?”. In this paper, we will defend an approach to the new demarcation problem that addresses complexities and nuances involved in distinguishing between good and bad science. Our approach describes epistemic and ethical norms that can help distinguish between science and non-science and between good and bad science, but it goes beyond this important first step and includes rules, policies, and procedures that serve to specify and implement those norms. We also provide a set of questions that can help provide practical guidance for deciding, for example, whether a research study should be admitted as evidence in a court of law or used in making decisions concerning the regulation of drugs. Our argument will proceed as follows. In Sect. 2 of this paper, we review the original demarcation problem and explain how efforts to develop necessary and sufficient conditions for distinguishing between science and non-science ran into significant difficulties because science is a highly diverse and complex activity and because these definitions were not well-suited for distinguishing among gradations of science. In Sect. 3, we review some of the key arguments for and against the value-free ideal and show how rejection of this ideal leads to the problem of how to distinguish between legitimate and illegitimate value influences. In Sect. 4 we review and critique some attempts to solve the new demarcation problem. In Sect. 5 we develop our approach to the new demarcation problem, which draws on lessons learned from failed attempts to solve the original problem. In Sect. 6, we use a case study involving regulatory decisions concerning drugs and chemicals to illustrate our approach. The Original Demarcation Problem The question of how to distinguish between science and non-science was a key epistemological issue in the philosophy of science in the twentieth century (Mahner 2007; Fasce 2017). The problem has its roots in logical positivism’s core tenet that knowledge must be verifiable.3 A belief (or statement) is verifiable if one can determine its truth or falsify by means of observations, tests, or experiments, or by logical or mathematical proofs (Carnap 1928; Reichenbach 1938; Ayer 1946). For example, the statement “Ethanol is flammable” can be verified by performing an experiment to determine whether ethanol ignites in the presence of oxygen and a flame. The statement “x + y = x − (− y)” can be proven mathematically by drawing inferences from the definitions of plus sign, the minus sign, and the equals sign. A statement like “The soul is immortal,” however, does not count as knowledge because it cannot be verified by observations, tests, experiments, or logical or mathematical or proofs. By the late 1950s, verificationist approaches to knowledge and language were falling out of favor among philosophers as result of by criticisms by Willard Quine (1951; 1953; 1955; 1960), Wittgenstein (1973 [1953]), Wilfrid Sellars (1956), Lewis Feuer (1951), and others.4 Even so, Popper proposed a highly influential solution to the demarcation problem that grew out of his critiques of verificationist ideas. Popper proposed a simple test for determining whether a theory or hypothesis is scientific: a theory is scientific if it is falsifiable; otherwise, it is not. A theory is falsifiable if an observation, test, or experiment could disprove it (Popper 1963). Pseudoscientific theories, such as theories from astrology, are not falsifiable, but scientific theories, such as theories from astronomy, are falsifiable. Popper also held that one can prove theories or hypotheses to be false, but one can never prove them to be true. Hence, the scientific method consists of proposing hypotheses and attempting to prove them false, or what Popper called conjectures and refutations (Popper 1959; 1963; Magee 1985). Popper’s motivation for solving the demarcation problem was not just intellectual; it was also practical. Popper realized that solving the problem would have important implications for practical disciplines, such as psychology and politics. Popper (1963) applied his solution to the demarcation problem to Freudian psychoanalysis and Marxism and argued that these were unscientific theories because they are not falsifiable. Since these theories are unscientific, we should be wary of using them in applied contexts, such as psychotherapy or politics, where human wellbeing is at stake (Magee 1985). Since Popper’s time, other writers have stressed the importance of being able to distinguish between science and non-science in numerous applied contexts, such as law, medicine, engineering, education, and public policy (Kitcher 1983; Resnik 2000; Haack 2014). The practical import of the demarcation problem is one reason why it remains an important issue in the philosophy of science (Pigliucci and Boudry 2013; Hansson 2017a). Popper’s formulation of the demarcation problem and his proposed solution was fairly simple. The problem is how to distinguish between science and pseudoscience and the solution is to develop a test that establishes necessary and sufficient conditions for making this determination. Subsequent philosophical inquiry has shown, however, that the demarcation problem is much more complex and subtle than it was originally conceived to be and that there is no simple test for distinguishing between science and pseudoscience (Hansson 1996; 2009; 2017b; Mahner 2007; Pigliucci and Boudry 2013; Fasce 2017; Boudry 2021). A key weakness of Popper’s solution is that it does not provide necessary conditions for regarding a theory or hypothesis as scientific because science includes foundational theories, hypotheses, concepts, and principles which are not falsifiable in any straightforward way (Resnik 2000). Important foundational principles in physics, such as the conservation of mass-energy, the law of entropy, and the uniformity of nature, cannot be falsified by individual experiments. If an experiment appeared to show that a physical process or system violates the conservation of mass-energy, for example, physicists would not reject this principle, but would question the soundness of the experiment or find a way of explaining why the principle is not being violated. Scientists accept or reject many foundational scientific ideas based on the explanatory role they play in a system of beliefs, not on the basis of particular tests or experiments (Duhem 1914; Quine 1955; Thagard 1988; Kitcher 1993). Popper’s solution also does not provide sufficient conditions for regarding a theory of hypothesis as scientific because some pseudoscientific theories and hypotheses are falsifiable. For example, we can test the astrological claim that “the planet Mars causes violent behavior” by observing rates of violence when Mars is in different positions relative to the Earth. The problem with theories from pseudoscience is not that they are unfalsifiable or that they are false, since history shows that many scientific theories and hypotheses (such as phlogiston and ether theory) turned out to be false. The problem is that proponents of these theories continue to accept them despite ample evidence that they are false (Thagard 1978). Since Popper’s time, philosophers, historians, and sociologists of science have proposed alternative solutions to the demarcation problem. Most of these solutions focus on units of analysis larger than hypotheses or theories, such as research communities, programs, disciplines, or paradigms, and some address historical, psychological, or sociological features of science (see e.g., Lakatos 1970; Merton 1973; Thagard 1978; Bunge 1982; Ruse 1996; Hansson 1996; 2009; 2017b; Mahner 2007; Pigliucci and Boudry 2013; Boudry 2021). Paul Thagard (1978), for example, asked not whether astrological theories are pseudoscientific but whether astrology, as a research discipline, is pseudoscientific. Thagard argued that astrology is a pseudoscience because astrologers cling to discredited theories and ignore disconfirming evidence (or anomalies). However, as Thomas Kuhn (1962) documented in his groundbreaking book The Structure of Scientific Revolutions, highly respected scientists, such as physicists in the early twentieth century who refused to accept quantum mechanics, also sometimes hold onto discredited theories and ignore anomalies. Imre Lakatos (1970) also focused on units of analysis larger than hypotheses or theories. Lakatos argued that we can use the notion of progressiveness to distinguish between scientific and non-scientific research programs: scientific research programs make progress over time, while unscientific programs stagnate. One problem with this view is that it is difficult to define or measure scientific progress (Laudan 1977). We will not catalog or critically examine the various approaches to the demarcation problem that have been proposed since Popper’s time.5 Instead, we will argue that attempts to solve the demarcation problem by articulating necessary and sufficient conditions for distinguishing between science and pseudoscience encounter two major and perhaps insurmountable difficulties: (1) adequately accounting for the diversity and complexity of scientific practice, and (2) distinguishing among gradations of science, from good to bad (Dupré 1993; Resnik 2000; Boudry 2021). Science is a highly diverse and complex activity with a wide variety of methodologies, procedures, datasets, inference patterns, hypotheses, models, theories, instruments, and traditions (Kuhn 1962; 1977; Hull 1990; Kitcher 1993; Ziman 2000; Boudry 2021). Science includes disciplines that are highly theoretical and mathematical, such as particle physics, cosmology, computer science, and bioinformatics, as well as disciplines that are applied and experimental, such as medicine, agronomy, pharmacology, and biochemistry. Some scientists use complex instruments, such as particle accelerators, gas chromatographs, or radio telescopes to gather data, while others collect data by interviewing people or observing human or animal behavior. Some scientists formulate specific hypotheses and test them prior to gathering data, while others use statistical algorithms to analyze large sets of preexisting data. Scientists work in every country in the world and in many different settings including academia, private industry, government, health care, law enforcement, and the military (Ziman 2000). Adequately accounting for all these different aspects of science is a monumental task for any definition of science to undertake, and this, we believe, is the main reason why definitions that use necessary and sufficient conditions to characterize science are likely to fail (Bunge 1982; Dupré 1993). Definitions that use necessary and sufficient conditions to define science also have difficulties with distinguishing among gradations of science. Although Popper originally conceived of the demarcation problem as the task of formulating a definition that would yield a “yes” or a “no” answer to the question, “is this hypothesis or theory scientific?”, philosophers now recognize that it is also essential to distinguish among gradations of science, because in practical contexts the important question is often “is this experimental finding, analysis, model, or study good enough science?” In a court of law, for example (discussed below in more detail), a judge must decide whether a research study performed by a professional scientist is good enough (e.g., unbiased, supported by data, reproducible) to admit into evidence. In drug regulation (also discussed below), a government advisory committee must decide whether a study published in a scientific journal is good enough to use in deciding whether to approve a drug for marketing. Gradation poses problems for using necessary and sufficient conditions to define science, because questions about gradation call for nuanced answers based on degrees of conformity to certain standards. For example, sanitation ratings are a type of gradation based on conformity to sanitation standards. A rating of “A” represents compliance with all the standards, “B” fewer of them, and so on. As a result of these and other problems with the original approach to solving the demarcation problem, many philosophers who are working on this topic no longer attempt to define science in terms of necessary and sufficient conditions but propose definitions that characterize science according to a list of epistemic criteria (Bunge 1982; Kitcher 1983; Dupré 1993; Ruse 1996; Resnik 2000; Hansson 2017a). While it is conceivable that definitions of science that use necessary and sufficient conditions could account for the complexity and diversity of scientific practice and its gradations, they are not as well-suited to this task as are definitions that define science by means of a list of criteria. Those who characterize science based on a list of criteria view the term ‘science’ as a Wittgensteinian family-resemblance word like art, politics, sport, and other terms that refer to complex human activities (Wittgenstein 1973; Bunge 1982; Dupré 1993).6 Using this approach, one cannot immediately dismiss a hypothesis (theory, or field of inquiry) as unscientific because it fails to conform to a particular norm; one must engage in a broader, more holistic assessment of the hypothesis. Also, under this approach, a hypothesis may be more or less scientific, depending on how many of the criteria it satisfies.7 The New Demarcation Problem In the previous section we argued that the original demarcation problem was framed as the question of how to develop a set of necessary and sufficient conditions for distinguishing between science and pseudoscience. However, what was thought to be a fairly simple and straightforward question—“is this theory or hypothesis scientific?”—turned out to be much more complex and nuanced than philosophers had realized. In Sect. 5 of our paper, we will apply insights from efforts to solve the original demarcation problem to the new one. But first, we will briefly describe the new problem and how some philosophers have attempted to solve it.8 The new demarcation problem, as mentioned earlier, emerges from rejecting the value-free ideal for science, which was part of logical positivism’s agenda for setting human knowledge on a solid foundation. Philosophers working within the positivist tradition, such as Carnap (1928), Reichenbach (1938), Nagel (1961), and Hempel (1965), developed theories of confirmation, explanation, and inductive reasoning that aimed to show how scientific knowledge is based on inferences from observations, tests, or experiments. According to this view, the decision of whether to accept or reject a hypothesis should be based on empirical evidence, not on external values. As new evidence emerges, hypotheses that were previously accepted may be rejected or revised. Science can make progress toward a more accurate and factual description of reality because its hypotheses and theories will reflect the empirical evidence that has been obtained and not personal, social, or other biases (Popper 1959). The positivists acknowledged that actual science often deviates from this ideal picture, due to human failings, such as biases and errors. Nevertheless, the positivists argued that scientists should aspire to overcome these problems so that science can be objective and truthful. For this reason, Douglas (2009) refers to this view as the value-free ideal. Philosophers, historians, and sociologists of science have developed several compelling arguments for rejecting the value-free ideal (for an overview, see Elliott 2022).9 Richard Rudner presented one of the most influential philosophical arguments against the value-free ideal in 1953, long before it became fashionable to claim that external values should influence scientific judgment and decision-making. Rudner argued that external values are essentially involved in the practice of accepting hypotheses because scientists must consider the consequences of mistakenly accepting or rejecting a hypothesis.10 For example, one should require more evidence to accept a hypothesis concerning the safety of a new drug than a hypothesis concerning the composition of Jupiter’s atmosphere because important values (e.g., human health and life) are at stake in the drug safety hypothesis, while less important values are at stake in the Jupiter hypothesis. Though Rudner’s arguments focused on the standards of evidence scientists use to accept hypotheses, Douglas (2000; 2009) extended his arguments by arguing that they apply to other contexts, such as data analysis and interpretation, and she also gave Rudner’s arguments a stronger ethical foundation (see also Elliott and Richards 2017). A second influential philosophical argument against the value-free ideal is based on the underdetermination of theory by evidence. This argument has its roots in the writings of Quine (1953; 1955; 1960) and Kuhn (1962; 1977) and has been developed at length by Helen Longino (1990; see also Anderson 2004; Biddle 2013; Brown 2020). According to this argument, empirical evidence often does not uniquely determine which theory (or model or hypothesis) one should accept, because inferences from evidence always depend on background assumptions.11 Thus, it is often the case in science that there are multiple theories that are empirically equivalent, and the decision concerning which one to accept cannot be settled by purely evidentiary considerations (Laudan and Leplin 1991). Many philosophers, including those who defend the value-free ideal, respond to the underdetermination problem by claiming that scientists can use epistemic values, such as simplicity, explanatory power, and the like, to choose between competing hypotheses that fit the evidence equally well (Quine and Ullian 1974; Laudan 1984; Thagard 1988). Critics of the value-free ideal take the appeal to values one step further and argue that scientists are sometimes justified in using external values to choose between empirically equivalent hypotheses because epistemic values may fail to settle which hypothesis is better and there are often moral or social reasons not to remain neutral in such situations (Biddle 2013; Elliott 2011; Frisch 2020). For example, the Intergovernmental Panel on Climate Change (IPCC) (2014) has been evaluating six models of global climate dynamics for the last decade or so. Critics of the value-free ideal could argue that if all of these models fit the data equally well, the IPCC could recommend that policymakers use the model that best promotes public and environmental health, provided that the IPCC clarifies the factors that shape their reasoning and the limitations of their conclusions and findings (Elliott and Resnik 2014; Intemann 2015; Frisch 2020). The IPCC could recommend, for example, that the models that provide the lowest estimates of global warming by 2100 should not be used in policymaking because these models will not convince the public that the problem of climate change is serious, but also that the models that give the highest estimates should not be used because these might be perceived as alarmist. One could argue, based on these value considerations, that the best models for communicating the risks of climate change to the public would fall somewhere between these two extremes.12 A third philosophical argument is based on the observation that many scientific terms, especially those used in the social and biomedical sciences, are not purely descriptive and have moral, social, or cultural connotations and implications (Alexandrova 2018; Dupré 2007). Some examples of value-laden scientific terms include marriage, rape, adultery, aggression, crime, alienation, race, ethnicity, gender, health, disease, disability, intelligence, depression, anxiety, sexual orientation, environment, ecosystem, invasive species, and pest (Dupré 2007; Ereshefsky 2009; Larson 2011; Rosenberg 2015). Although some philosophers (e.g., Boorse 1977; Schaffner 1993), have tried to reinterpret scientific words with normative connotations in descriptive terms, Kevin Elliott (2017) challenges this idea. Elliott argues that the terms scientists use, as well as the ways they frame information and the manner in which they categorize phenomena, all have the potential to privilege some values over others (see also Larson 2011). According to Elliott, since there are often no value-neutral ways of handling these value-laden aspects of scientific language it is better for scientists to recognize these normative aspects of scientific language and to incorporate external values in their choices about language rather than to ignore this value-laden aspect of their work. A fourth philosophical argument against the value-free ideal is based on insights from studies of how private companies and government funding agencies use money and power to shape the research agenda and, ultimately, the content of science (Holman and Bruner 2017; Resnik 2007; 2009; Michaels 2008). Private companies can shape the research agenda by funding and publishing studies that promote their economic interests and not publishing studies that undermine their interests. While the company’s interests may not affect the outcome of any particular study, they can still have a cumulative effect on the entire research field and therefore the evidence that is available for other researchers to use (Elliott and McKaughan 2009; Holman and Bruner 2017). For example, if a drug company funds ten clinical trials comparing its medication to competing products and publishes only the five studies that show that its product is superior, the research record will reflect this bias (Krimsky 2003; Resnik 2007; Michaels 2008). Although government science agencies usually require that funded investigators publish their research, they can still use their money and power to significantly influence the content of entire scientific fields (Resnik 2009). For example, research on environmental health disparities has been supported, in large part, by government funding (Schlosberg 2009). Since modern science is difficult to do without significant financial support, external values that impact funding decisions inevitably affect the content of science. As in cases where values influence scientific language, it is better to consider these influences in an intentional fashion rather than letting them play out without attending to them. We would be remiss if we did not mention that philosophers have responded to these critiques with defenses and reinterpretations of the value-free ideal (see Jeffrey 1956; Betz 2013; John 2015; Hudson 2016; Lacey 2017), and the controversy about the relationship between science and values is not entirely settled (see Douglas 2016; Elliott 2022). It is not our aim in this paper to adjudicate the dispute between proponents and critics of the value-free ideal. Rather, our purpose is to reflect on a key problem that arises from rejecting the value-free ideal and consider how to best to address it. The key problem for those who reject the value-free ideal is how to consistently and coherently distinguish between legitimate and illegitimate value influences (Douglas 2009; Hicks 2014; Resnik and Elliott 2019). This is an important issue not only for those who reject the value-free ideal but also for society, because, as we have seen, external values can have a powerful and corrupting influence that threatens the integrity, reliability, and trustworthiness of science. Science derives its trustworthiness from being regarded by the public as a reliable and impartial provider of knowledge and expertise in a pluralistic society in which people disagree about fundamental values (Jasanoff 1998; Ziman 2000; Pielke 2007; Resnik 2009; Bright 2018). When the public views science as driven by the economic, social, or political values or interests of particular organizations or groups, it may lose trust in science, which can have devastating impacts on science and society. When the public loses trust in science, policy discussions can degrade into political battles, as has occurred in the debate about climate change, and laypeople may ignore evidence-based health advice from physicians and government health agencies, as has occurred during the COVID-19 pandemic (Collins and Evans 2017; Mann 2021; Saphier 2021). Also, erosion of public trust can make people less willing to fund science, participate in clinical trials, or otherwise support the research enterprise, all of which can have negative impacts on science and society (Resnik 2011). Given the serious epistemic, social, and political risks associated with allowing external values to influence science, it is incumbent on critics of the value-free ideal to show how one can prevent illegitimate value influences while permitting legitimate ones (Resnik and Elliott 2019; Koskinen and Rolin 2022). This is not an easy problem to solve because it seems hypocritical to say that some value influences are acceptable while others are not. How can one consistently argue that it is acceptable for an academic scientist to allow a concern for public health to affect their interpretation of toxicology data while at the same time maintaining that it is not acceptable for an industry scientist to design a study in a way that it promotes the company’s profits? To deal with such questions, one must develop an approach that clearly and consistently shows why some value influences are problematic while others are not. The new demarcation problem is therefore similar to the original one in the sense that it is concerned with the practical applications of science, i.e., how science is used in law, medicine, education, public policy, and so on. If we use theories (or hypotheses, principles, models, or concepts) to make decisions with important implications for human health, the environment or other things we value, then we expect those theories to be reliable, impartial, and trustworthy (Resnik 2000; 2009). This practical concern remains one of the key motivations for drawing some boundaries between science and pseudoscience, as well as between good science and bad (i.e., biased, fraudulent, erroneous) science. However, the new problem is much more complex and multifaceted than the original one because it is explicitly concerned with answering questions about gradations of science, from good to bad, and because there are so many ways in which values can potentially influence science. Before turning to our own preferred approach to this problem, the next section considers some of the other available strategies for addressing it. Protecting the Integrity of Science Philosophers who reject the value-free ideal have explicitly or implicitly proposed various ways of distinguishing between legitimate and illegitimate values influences on science. Unfortunately, all of these efforts, as we shall argue below, have weaknesses and shortcomings. This is understandable, because the existing scholarship developed primarily in an effort to challenge the value-free ideal and has only secondarily turned to the issue of distinguishing between appropriate and inappropriate value influences (Holman and Wilholt 2022). We will not review every approach to distinguishing between legitimate and illegitimate value influences on science in this paper but will focus on several influential, representative accounts. Current approaches to the new demarcation problem can be categorized as axiological, functionalist, consequentialist, coordinative, or systemic (Holman and Wilholt 2022; for a related but slightly different categorization, see Elliott 2022). Axiological approaches claim that external value influences are appropriate when they promote the “right” values; functionalist approaches claim that external value influences are legitimate only when they play the appropriate role in scientific inquiry; consequentialist approaches claim that external value influences are appropriate when they achieve particular effects or accomplish particular aims; coordinative approaches claim that external values influences are legitimate when they involve appropriate coordination between researchers, the scientific community, and the larger public that facilitates assessment, discussion, and management of values; and systemic approaches claim that external value influences are legitimate when the community of inquirers is structured in such a way as to provide adequate critical scrutiny of those influences. Following Holman and Wilholt (2022), we begin with axiological approaches first, since they demonstrate, in stark terms, the opportunities and dangers associated with incursion of external values into science. Axiological approaches hold that moral, social, or political values should play a decisive role in guiding, structuring, and governing scientific inquiry. Several philosophers (e.g., Kitcher 2001; 2011; Kourany 2010; Brown 2020) have defended this type of view. Philip Kitcher (2001; 2011) argues that science should be guided by the values that well-informed deliberators who are considering rules for the structure of society would adopt. Kourany (2010) contends that science should reflect values arrived at through ethical reasoning. For example, she claims that scientists should not pursue avenues of inquiry that could have racist implications, such as the relationship between race, genetics, and intelligence (Kourany 2010). Alex John London (2022) develops a similar approach in the realm of clinical research. London argues that clinical research is a cooperative social activity carried out to promote and protect human rights and egalitarian ideals of social justice. Axiological approaches tend to appeal to the Baconian idea that science should improve the human condition (Bacon 2000; Kitcher 2001). For some proponents of the axiological approach, scientific research represents an opportunity to advance moral or political goals, such as democracy, social justice, or protection of human rights or the environment (Schroeder and Andrew 2017; Bright 2018). However, because axiological approaches do not place systematic constraints on the influence of external values on science, they threaten the trustworthiness of science by appealing to values that are likely to be controversial. We live in a highly polarized society in which people fundamentally disagree about moral and social issues, such as abortion, capital punishment, gun control, genetically modified crops, climate policy, immigration, and affirmative action, and the fundamental values that give rises to these disagreements (Gutmann and Thompson 1998; Resnik 2009). Given that science is typically regarded as a relatively neutral source of information, it seems problematic at best, and potentially disastrous at worst, to incorporate potentially controversial moral, social, and political assumptions into scientific reasoning. Some scholars embrace egalitarian conceptions of justice, for example, but many people accept different accounts of justice, such as libertarianism and utilitarianism. Some people might think that science should promote economic development, national security, or even religious doctrines. By wedding scientific inquiry to the advancement of particular moral, social, or political values, axiological approaches risk politicizing and polarizing science. Some axiological approaches could also threaten the integrity of science if they do not require commitment to widely accepted epistemic and ethical norms that govern scientific inquiry, such as honesty, rigor, reproducibility, openness, transparency, and freedom of inquiry.13 If one holds that science should serve the “right” social or political values, then one could potentially justify epistemically problematic actions to promote those values, such as fabrication or falsification of data or suppression of ideas, hypotheses, and theories. History provides a stark reminder of what can happen when science is subservient to politics or religion. Galileo Galilei, Giordano Bruno and Mendelian geneticists in the former Soviet Union faced significant repercussions, including imprisonment or death, for defending scientific theories that contravened political or religious values (Resnik 2009). In more recent times, politically motivated repression of scientific research and debate continues to be a major concern, as illustrated by efforts by the George W. Bush and Donald J. Trump administrations to censor climate change research conducted by US federal government scientists (Mann 2021). Functionalist approaches address these concerns by limiting the roles that external values play in science. The most influential of these approaches has been defended by Heather Douglas (2009). In her book, Science, Policy, and the Value-Free Ideal, Douglas (2009) argues that values (epistemic and external) should play only an indirect role in science.14 According to Douglas, values function in a direct role when they operate the way evidence does, by providing reasons in support of scientific statements or beliefs. Values function in an indirect role when they do not function as evidence but rather guide decisions about how much evidence is sufficient to accept a theory or hypothesis. Douglas argues that the key to maintaining appropriate roles for values in science is to ensure that they do not play a direct role when scientists assess hypotheses or theories. The fact that a theory or hypothesis promotes a particular external value, such as public health, should never be a reason for accepting that theory or hypothesis, though it might be used as a reason for setting a standard of evidence used to evaluate this hypothesis. While Douglas’ distinction between direct and indirect roles for values provides some insights into how values should function in scientific research, it does not adequately protect the integrity and trustworthiness of science because it does not clearly distinguish between illegitimate and legitimate value influences in an indirect role.15 There is ample evidence that values can significantly bias research even when they only operate in an indirect role (Michaels 2008). For example, private companies and the researchers who work for them have manipulated experimental designs and statistical models to favor their financial interests and have suppressed data and results that could undermine those interests (Resnik 2007; McGarity and Wagner 2008). Most people would regard this type of value influence as illegitimate, even though values do not appear to be functioning as evidence, since values are influencing the type of evidence that investigators obtain and how they share it with the scientific community (Steel and Whyte 2012). Another problem with Douglas’ approach is that one might argue that there are some situations in which external values legitimately play a direct role in scientific judgment and decision-making (Biddle 2013; Elliott and McKaughan 2014). In the climate change case discussed above, for example, one could argue that climatologists may use external values, such as promoting public health or protecting the environment, when choosing among competing models of global climate that fit the data equally well (Intemann 2015; Frisch 2020). Steel (2015) also develops a functionalist approach. Steel argues that epistemic and external values can both play an important role in scientific inquiry, but that external values should never override epistemic ones in the design or interpretation of research that is feasible and ethical (Steel and Whyte 2012). External values can play a role in these sorts of judgments or decisions only when competing choices are equally compatible with empirical evidence and epistemic values. For example, suppose that the data from a toxicology experiment provide equal support for two different interpretations of the safety of a chemical. A scientist could decide in this situation to opt for the interpretation that promotes external values, such as public health or corporate profits. However, if the data clearly supported a different interpretation, the scientists should choose that one. If two different research designs equally satisfy epistemic criteria, such as rigor, testability, and consistency, a scientist could choose the design with an eye toward promoting external values. However, a scientist should not allow these values to affect research design decisions when epistemic values favor one type of design over the other. Although Steel’s approach also offers some useful insights into how values function in scientific research, it also does not provide an entirely satisfactory solution to the new demarcation problem. First, it is not clear that Steel’s view is comprehensive enough, given that it focuses primarily on the role of external values in research design and data interpretation. However, as we have seen, external values could corrupt science in other stages of research, such as problem selection, data analysis, peer review, and publication (Resnik and Elliott 2019). Steel does not indicate whether external value influences should be limited in these other contexts, but one might argue that they should be to protect the integrity of scientific research. Second, external values can arguably have problematic effects on research even when they do not clearly override epistemic ones. In chemical toxicology studies, for example, scientists must make choices pertaining to many different aspects of experimental design, including the variables to be measured, dosing levels and schedules, the animals to be used, control groups, the length of time of the study, and so on. External values often guide these choices long before a potential conflict with epistemic values arises. For example, an academic scientist may decide to measure the impact of a chemical on the endocrine system because of possible implications for human health. Conversely, a scientist working for a company that manufactures this chemical might decide not to measure its impact on the endocrine system to avoid collecting data that could show that the chemical poses a risk to human health. In some cases, these influences of external values could be problematic even if they did not clearly conflict with epistemic values. Consequentialist approaches to the new demarcation problem focus instead on whether value influences enable science to achieve the right effects or aims. For example, Intemann (2015) argues that scientists should incorporate values into their work in a manner that enables them to achieve aims that are democratically endorsed. One could also use ethical analysis to identify particular effects or aims that science should achieve. Although Holman and Wilholt (2022) distinguish consequentialist approaches from axiological approaches, they are very similar and have the potential to run into the same sorts of problems. For example, Steel (2017) worries that scientists could violate important epistemic constraints in the course of trying to achieve particular aims. Thus, consequentialist approaches, like axiological and functionalist strategies, run the risk of failing to protect the integrity, reliability, and trustworthiness of science against potentially problematic value influences throughout the entire process of scientific inquiry, from problem selection and research design to data analysis and hypothesis acceptance. Coordinative approaches to the new demarcation problem focus on aligning the practices of science with the expectations of the audiences who receive scientific information. This coordination could take a variety of forms. One approach is to adopt conventional standards that establish particular ways of handling value judgments so that everyone knows what to expect (Wilholt 2009; John 2015). Another approach is to promote transparency about value influences so that those receiving scientific information can determine whether they agree with those underlying value influences (Elliott and Resnik 2014; Elliott and McKaughan 2014). Yet another approach is to foster engagement between scientists and those interested in or affected by the research so that it can be performed in a way that meets their expectations (Douglas 2005; Intemann 2015; Parker and Lusk 2019). Unfortunately, even though efforts to align the practices of science with its users make a great deal of sense, coordinative approaches also have weaknesses that prevent them from serving as comprehensive strategies for addressing the new demarcation problem. In general, these approaches tend to face a dilemma. On one hand, if they adopt fixed standards that are applicable under all circumstances (e.g., John 2015), then they are fairly unlikely to serve the interests of all audiences. On the other hand, if they allow scientific practices to vary based on the specific needs or concerns of particular users (e.g., Elliott and McKaughan 2014; Parker and Lusk 2019), then they create the potential for confusion because it is difficult to be entirely transparent about all the ways in which values influence scientific work (Elliott 2021). Moreover, coordinative approaches tend to share the epistemic weaknesses of the axiological, functionalist, and consequentialist approaches, namely, that epistemic standards could be violated in the name of achieving the goals of particular audiences (Steel 2017). Finally, systemic approaches shift the focus from the individual level to the social level and argue that value influences in science are appropriate as long as the structure of the scientific community has the appropriate characteristics to maintain the integrity of science. For example, Longino (1990) argues that the key to achieving scientific objectivity is not to banish external values from science but to structure scientific inquiry in such a way that judgments and decisions shaped by external values receive critical scrutiny in the marketplace of ideas. She defends four criteria that she claims are necessary for generating critical scrutiny: including publicly recognized venues for criticism, achieving uptake of criticism, having shared standards, and ensuring tempered equality of intellectual authority. Objectivity, according to Longino, emerges from a process of “checks and balances” on values. For example, if a chemical company publishes a study showing that its product is safe, a government-funded academic researcher may publish a study showing that it is not, and objective knowledge can emerge as the byproduct of this interplay of competing values, i.e., profit vs. public health. Despite the benefits of drawing attention to the role of the scientific community in addressing the influences of external values, systemic approaches still have weaknesses. For example, Longino’s approach raises concerns because there is no guarantee that objectivity will emerge from Longino’s procedures, especially when there are substantial differences in resources and power between opposing sides of a scientific dispute. For example, if a chemical company has enough money to sponsor ten studies showing that its product is safe, but the government only has enough money to sponsor one study showing that it is not, the chemical company may emerge victorious, because it has more money than the government. Likewise, a political group that attempts to impose a racist, sexist, or homophobic agenda on a scientific discipline will emerge victorious if it has more power than opposing groups. Moreover, it is not clear that highly problematic values should be allowed to influence science, even if steps are taken at the level of the scientific community to counteract them (Intemann 2017). Thus, even though one can attempt to mitigate these sorts of problems by adding additional restrictions on the structure of the scientific community, it seems questionable to try to manage the influences of external values on science solely by influencing the structure of the scientific community. Toward a Solution to the New Demarcation Problem Our overview of attempted solutions to the old demarcation problem in Sect. 2 and the new demarcation problem in Sect. 4 converge on the same conclusion. In both cases, efforts to develop necessary and sufficient conditions for distinguishing science from non-science or good science from bad science end up running into difficulties (see also Koskinen and Rolin 2022). Although the philosophers we discussed in Sect. 4 did not conceive of themselves, as far as we know, as providing necessary and sufficient conditions for distinguishing between legitimate and illegitimate value influences on science, it is clear that their approaches to the new problem tended to offer fairly simple criteria for determining whether external value influences are appropriate and do not adequately account for the diversity and complexity of the relationship between scientific practice and external values. Our critiques of these approaches to the new problem emphasized the variety of ways that values can impact science. Values can impact science at many different stages of inquiry, and it is doubtful that a single criterion for distinguishing between appropriate and inappropriate influences will adequately account for the diversity and complexity of all these influences. Given the complexity and diversity of value influences on science, we believe that efforts to distinguish between legitimate and illegitimate influences should focus on whether researchers are complying with epistemic and ethical norms that are constitutive of good science, rather than on some particular criteria of legitimacy. A set of norms is listed in Table 1. These norms can be used to classify science from “good” to “bad,” depending on how well it complies with the norms. On our view, a study could qualify as scientific but not be good enough to use in an applied context (such as making a legal or regulatory decision) because external values have inappropriately influenced it in some way. We do not claim originality for these norms; the list in Table 1 has much in common with norms developed by Merton (1973), Kuhn (1977), Thagard (1988), Kitcher (1993), Resnik (1998), Resnik and Elliott (2019), Elliott (2022), Koskinen and Rolin (2022), Shamoo and Resnik (2022), and others. The norms apply to all stages of the research process, from problem selection to data collection to publication and data sharing, and to a wide range of disciplines.Table 1 Scientific norms (based on Resnik and Elliott 2019) 1. Honesty (honestly communicating with other scientists and the public) 2. Rigor (subjecting research to rigorous tests; considering the limitation of one’s methods and results) 3. Objectivity (minimizing or controlling experimental, theoretical and other biases, including conflicts of interest) 4. Evidentiary support (drawing inferences based empirical evidence and/or sound logical, statistical, or mathematical arguments) 5. Carefulness (minimizing human and instrumental errors; keeping good research records) 6. Transparency (disclosing methods, materials, assumptions, values and interests) 7. Openness (sharing data, results, ideas, and materials) 8. Reproducibility (taking steps to ensure that research is reproducible, such as keeping good records, disclosing methods and assumptions, and minimizing or controlling biases) 9. Accountability (being accountable for one’s research; taking responsibility for one’s research; responding to criticisms of one’s research, including allegations of misconduct) 10. Self-Correction (carefully scrutinizing research during peer review and after publication; retracting or correcting flawed research; attempting to reproduce results) 11. Intellectual Freedom (freedom of thought, discussion, debate, publication) 12. Fair sharing of credit (giving proper credit on publications and other scientific works; acknowledging previous research; respecting others’ intellectual property) 13. Respect (treating one’s colleagues and students with respect; respecting intellectual property rights) 14. Safety (helping to ensure that the research environment is safe and taking appropriate steps to prevent, minimize, or mitigate physical, chemical, biological, and psychosocial risks, including risks related to harassment or inappropriate conduct) 15. Stewardship (making good use of research resources, including materials, facilities, and funding) 16. Social responsibility (promoting benefits and minimizing or avoiding harms from one’s research) 17. Protection of human and animal research subjects (only for research disciplines that work with animals or humans) 18. Engagement (consulting with stakeholders to identify important epistemic or ethical issues that need to be addressed) The norms can be understood within the framework of social epistemology (Longino 1990; Resnik 1996). Social epistemology characterizes knowledge production as a social activity governed by goals and norms. Knowledge production requires cooperation, collaboration, and trust among knowledge producers (i.e., members of scientific laboratories, research groups, or communities), as well as cooperation, collaboration, and trust between knowledge producers and the larger society (i.e., the public; Rolin 2015). Thus, science has norms because science itself is a society, and science is a socially sanctioned activity that exists within a larger society (Resnik 1996). Science is a socially sanctioned activity (as opposed to an illicit activity) because it produces something that the public regards as valuable: reliable, trustworthy knowledge that serves the common good. The norms of science, therefore, are based on three foundations: (1) science’s general epistemic aims (i.e., production of reliable, impartial knowledge); (2) characteristics of the research environment necessary to achieve those epistemic aims; and (3) public accountability (i.e., science’s practical aim of providing trustworthy knowledge in a manner that serves the common good).16 For example, some of science’s norms, such as honesty, rigor, objectivity, reproducibility, and carefulness, directly promote science’s epistemic aims; while others, such as openness, fair sharing of credit, respect, and safety, help to foster a research environment in which people can work together collaboratively and cooperatively to achieve common goals; and still others, such as protection of human and animal research subjects, social responsibility, and engagement, help to ensure that scientists are accountable to the public (Resnik 1996; 1998; Elliott 2011; 2017). See Fig. 1.Fig. 1 Relationship between Scientific Aims, Norms, Rules, Traditions, Policies, Procedure, and Practice (based on Resnik and Elliott 2019) Since the norms of science promote general epistemological and practical aims, our approach could be construed as axiological. However, we do not believe that our approach is susceptible to the main objection to other axiological approaches, i.e., that they run the risk of politicizing and polarizing science, because the aims we endorse, and the norms they justify, are highly generic and are therefore compatible with many different social and political values. Although the influences of specific moral, social or political values, such as protection of the environment or promotion of social justice, might ultimately be allowed to influence scientific reasoning via norms like social responsibility or engagement, the norms in Table 1 operate at a more general and less controversial level. The general aims of science, and the norms that flow from them, provide a basic framework within which deliberation about more specific research aims and values can take place (see e.g., Elliott and Resnik 2014; Hicks 2014; Intemann 2015). One of the main reasons for adopting our normative approach is that it accords well with the insight that the characteristics of good scientific research can vary depending on the context. Because these norms rest on the aims of science, the relative weight given to different norms can vary somewhat depending on the aims associated with specific research contexts (Lusk and Elliott 2022). When researchers are doing applied work for regulatory purposes, for example, norms like social responsibility and engagement take on special significance. These norms would not be absent in other contexts, but their implementation would likely take different forms. Building on this point that the norms can be implemented in different ways, it is crucial to recognize that the norms are mere platitudes with little practical value unless they are enforced, implemented, and supported by rules, conventions, policies, and procedures (Mantzavinos 2020). With this in mind, another strength of our norm-based approach to addressing the new demarcation problem is that we can draw on the array of rules, conventions, policies, and procedures that have already been developed and implemented by research institutions, funding agencies, private sponsors, professional societies, and scientific journals (Table 2). It is important to note that these rules, conventions, policies, and procedures are not always spelled out explicitly in professional codes; instead, professional communities frequently develop conventional standards or expectations regarding study design, data analysis, and interpretation. Wilholt (2009) has previously argued that these conventional standards help guide scientists in their responses to value judgments.Table 2 Rules, conventions, policies, and procedures for the conduct of science (based on Resnik and Elliott 2019) Policies that define and prohibit research misconduct, such as rules pertaining to fabrication or falsification of data or plagiarism; Procedures for reporting, investigating, and adjudicating research misconduct; Policies and procedures for keeping good research records; Policies and procedures for auditing data and other research records; Rules or conventions for designing experiments; Rules or conventions concerning standards of evidence for accepting or rejecting hypotheses; Rules or conventions concerning good statistical practice; Rules or conventions for processing digital images; Rules of deductive logic (e.g. the rule of non-contradiction, modus ponens); Policies for disclosing and describing one’s materials and methods in publications and grant proposals; Policies for sharing data, research materials (e.g. biological samples and chemical reagents), and computer codes used in statistical programs for analyzing data; Policies and procedures for registering clinical trials in publicly available databases; Policies for disclosing and managing financial and other interests related to research; Policies and procedures pertaining to the confidentiality, rigor, and fairness of peer review for scientific publications; Policies and procedures pertaining to the confidentiality, rigor, and fairness of peer review for grants or contracts; Policies for assigning authorship on publications; Policies and procedures for correcting or retracting publications; Rules and procedures for promoting the reproducibility of research, such as disclosure of materials and methods (discussed above), sharing and auditing data (discussed above), and standards for organizing and analyzing data and designing experiments; Rules pertaining to the ownership and use of intellectual property; Policies on academic freedom; Policies pertaining to hiring, tenure, and promotion; Policies pertaining to equity, diversity, and inclusion in science; Rules, policies, and procedures pertaining to research with animal or human subjects; Rules and policies related to social responsibility in research; Policies pertaining to education and training in responsible conduct of research (i.e. research ethics, good scientific practice) Thus, according to our view, distinguishing between legitimate and illegitimate value influences on scientific research is a complex, context-dependent, and holistic determination. One must examine the extent to which a variety of norms have been met and how they have been met. To do so, one must typically determine whether scientists are following the rules, conventions, policies, and procedures created by scientific societies, research institutions, funding agencies, regulatory bodies, and other stakeholders. In addition, there may be conflicts between different norms as well as questions about how best to implement them (Elliott 2022). Addressing these conflicts and questions typically requires complex, holistic, context-dependent judgments. Also, there may be gradations in the extent to which the norms are met, ranging from exemplary science, to good science, to bad science, to not science at all (e.g., pseudoscience). Thus, in some cases there may be significant philosophical work involved in assessing the extent to which values have influenced a research project, and whether this influence has been appropriate or inappropriate. To begin this analysis, one can ask some standard questions that we have listed in Table 3. Although this might seem like a somewhat long and overwhelming list, we provide a case study in Sect. 6 that illustrates how specific questions become particularly salient given the issues at stake in specific cases.Table 3 Questions a scientist or non-scientist could ask when determining whether a study complies with scientific norms Have the researchers honestly reported their data and results? Is there any reason to suspect fabrication or falsification of data or other types of deception? Have the researchers carefully and transparently described and disclosed their aims, methods, materials, and background assumptions? Is the study well-designed to achieve its aims? Are the study aims justifiable? Does the research seek to answer important scientific questions? Does the research have potentially significant impacts for public health, the environment, society, or the economy? Does the research include appropriate controls and other means of limiting bias? Is the study statistically well-designed? Is the sample size large enough to support the results of the study? Have digital images been processed appropriately? Has the hypothesis, theory, or model been subjected to rigorous tests? Have the researchers discussed limitations of their work? Does the hypothesis, theory, or model have evidentiary support? How much? Is the data analysis appropriate, given the aims, methods, and study design? Does the interpretation of the data proposed by the researchers have evidentiary support? Have the researchers overinterpreted the data? What assumptions were made in data interpretation? Have the researchers stated those assumptions? Have the researchers abided by the rules or conventions of their scholarly community when designing experiments and analyzing and interpreting results? When the researchers have diverged from rules or conventions, have they explained and justified those decisions? Have the researchers kept good records? Have members of the research team had access to the data and records throughout the process of research? Are the researchers appropriately sharing data, materials, and methods? Are there any data that are not being shared to protect privacy or proprietary interests, or for other reasons? Have the researchers audited their data and records? Have the researchers disclosed sources of funding and financial or other interests? Do the researchers have any conflicts of interest that could bias the research? Have the researchers taken appropriate steps to manage conflicts of interest? Is the research reproducible? Have outside researchers attempted to reproduce it? Has the research been peer reviewed? Has the research been published in a high-quality journal? If the research is likely to have significant impacts on particular stakeholders, have they had an opportunity to review or comment on it and, if appropriate, influence the research design? Have the researchers considered the social ramifications of their work and taken appropriate steps to address ethical or social concerns that it could raise? Do the researchers face any corporate or governmental restraints that limit their freedom to candidly discuss their research? Have the researchers provided appropriate protections for animal or human research subjects? A final strength of our proposed approach is that it accords well with steps that are already being taken to address the value-ladenness of science in applied decision-making contexts. To take one example, judges often face difficult choices about whether to admit expert testimony into the courtroom, since attorneys may call witnesses who offer testimony based on novel or controversial theories, hypotheses, concepts, or methods. For example, in the 1980s, DNA fingerprinting evidence was controversial, because it was new and had not been well-validated or tested, but today it is routinely admitted into the courtroom (Roewer 2013). In a landmark case, Daubert v. Merrell Dow Pharmaceuticals, Inc. (1993), the U.S. Supreme Court ruled that judges can admit expert scientific testimony based on whether the expert’s knowledge is reliable or based on the scientific method.17 The Court listed several factors that judges can consider when deciding whether to admit testimony based on theories, hypotheses, or concepts into the courtroom, including falsifiability, peer review and publication, error rate, and acceptance by the scientific community (Daubert v. Merrell Dow Pharmaceuticals, Inc. 1993). However, the Court noted that there could be other factors it did not describe and that none of the factors constitute necessary conditions for admitting scientific testimony into the courtroom. The Court offered the factors as guidelines rather than exhaustive and dispositive rules (Rothstein et al. 2011). Thus, judges are already using an approach that accords with our preferred solution to the new demarcation problem. To further implement our approach in the courtroom, we would recommend that judges use a list of questions like those described in Table 3 to determine whether an expert’s testimony complies with scientific norms. If the expert’s testimony significantly deviates from scientific norms, then the judge could decide not to admit their testimony. A Case Study: The Food and Drug Administration To provide further illustration of the way our approach would work in practice, we offer a brief case study involving the U.S. Food and Drug Administration (FDA)’s decision-making. The FDA regulates foods, drugs, biologics, medical devices, cosmetics, and veterinary and tobacco products marketed in the U.S. It has the authority to approve new products or new uses of approved products; to oversee marketing, labelling, and manufacturing of products; to issue warnings on products; or to require that products be removed from the market. The mission of the FDA is to promote public health and safety (Food and Drug Administration 2018a). To obtain approval for a new drug, a manufacturer must submit an application to the FDA and conduct animal experiments and human clinical trials to gather evidence concerning the drug’s safety and efficacy (Food and Drug Administration 2018b). The FDA reviews evidence submitted by the manufacturer to determine whether its drug is safe and effective enough to be approvable for marketing. The FDA uses panels of experts from the relevant scientific and medical disciplines to make recommendations concerning drug approvals. The expert panels review evidence pertaining to safety and efficacy submitted by manufacturers and considers evidence from other sources, such as independent studies published in peer-reviewed journals (Food and Drug Administration 2018b). A key question these panels face is whether a study should be included in the review of evidence. If a study does not meet appropriate scientific and ethical standards, the panel may decide not include it. While the FDA has issued some guidance to manufacturers on how to design and conduct clinical trials (Food and Drug Administration 1998), this guidance often is subject to interpretation, and panel members must often decide how to evaluate the studies when they review the evidence. Deciding which studies to include in the review of evidence can be a difficult task, because research has shown that clinical trials funded by drug companies often reflect the company’s bias (for a review of the evidence, see Krimsky 2003; Sismondo 2008; McGarity and Wagner 2008). As discussed above, companies can achieve outcomes favorable to their products by various means, such as by manipulating study designs or data analyses, or by selective publication of data and results (Holman and Elliott 2018; Resnik 2007; Lexchin 2012). To apply our approach to the new demarcation problem to the question of which studies should be included in the review of evidence for drug approval, we would recommend that FDA expert panels use a list of questions like those described in Table 3 to determine whether the studies comply with scientific norms. If a study significantly deviates from scientific norms, then the panel members could decide not to include it in their review of evidence. Medical researchers, epidemiologists, and biostatisticians (see e.g., Furberg and Furberg 2008; Straus et al. 2019) have been moving in this direction since the 1990s by developing guidelines for assessing clinical evidence. These guidelines address issues related to research design, data analysis, data reporting, and other scientific issues like those discussed in this paper and described in Tables 1, 2, and 3. The norms, rules, and questions described in those tables could strengthen and supplement the guidelines that have already been developed. Admittedly, in actual cases these deliberations about which studies to accept can become very complex. Thus, even though our approach provides a framework for distinguishing appropriate influences of values from those that are problematic, it does not provide a simple recipe for arriving at conclusions that everyone will agree on. Consider, for example, a prominent debate that has engulfed the FDA’s decision-making around the chemical bisphenol A (BPA), which is used in many products, including the lining of food cans (Resnik and Elliott 2015). Many scientists worry that BPA has endocrine-disrupting effects that can contribute to developmental disorders, obesity, diabetes, and numerous cancers (vom Saal and Frederick 2019). In 2008, the FDA concluded that BPA was safe at current levels of human exposure (Food and Drug Administration 2018c). They based this conclusion largely on two studies that were performed according to standardized protocols that are typically used for informing regulatory decision-making (Tyl 2009). This approach was very controversial, however, because it placed relatively little weight on a number of academic studies that provided evidence of potential harm from BPA at human exposure levels (Myers et al. 2009). This case illustrates the challenges of navigating the role of values in science because investigators on opposing sides of this bitter conflict worry that the opposing side is inappropriately influenced by values; for example, those who defend BPA could be influenced by financial values and the entrenched paradigms of the field of toxicology, while those who challenge its safety could be influenced by public-health-oriented and environmental values (see e.g., Elliott 2016; Vandenberg and Prins 2016). In order to approach this case using our norm-based approach, one would want to examine the quality of the studies based on the norms, rules, and questions described in the tables above. For example, to what extent were the underlying data made available from the studies under consideration? How well were the methods described, and how relevant were those methods for addressing the regulatory question at issue? Were the results reported in a manner that gives regulators the information they need to assess the studies’ relevance and reliability (Moermond et al. 2016)? Did the investigators report important conflicts of interest? Were the studies peer reviewed? How do the study results compare to the findings from other studies? Moreover, to the extent that the investigators had to make important value judgments when interpreting the studies, were they transparent about the nature of those judgments and the reasons for making them in particular ways (Elliott and Resnik 2014)? Were the judgments made in ways that meet the conventional standards of the discipline and justifiable ethical and political principles (Wilholt 2009)? Importantly, working through these questions can incorporate a great deal of scientific and philosophical analysis. The crucial sticking point in the BPA case is that there is a clash between opposing considerations. On one hand, the studies prioritized by the FDA were performed according to Good Laboratory Practice (GLP) guidelines—which establish strict requirements for record-keeping—as well as standardized methodologies established by the Organization for Economic Cooperation and Development (OECD) for the purposes of regulatory decision-making (see Elliott 2016). On the other hand, the academic studies emphasized by the FDA’s critics were published in peer-reviewed journals and incorporated cutting-edge methodologies that many regarded as better designed for uncovering the endocrine-disrupting effects of BPA (Myers et al. 2009). Critics of the FDA’s approach also worried that the investigators who performed the FDA’s preferred studies had conflicts of interest because of their connections with the chemical industry, while the FDA’s defenders claimed that academic studies often suffered from poor quality control and unvalidated methodologies. Moreover, in the background of all these debates were value judgments about how to interpret studies that appeared to show harmful effects from BPA at low doses of exposure but not at higher doses (Vandenberg et al. 2019; vom Saal and Frederick 2019); many endocrinologists regarded these studies as providing convincing evidence of harm, while many toxicologists remained unconvinced (Gore 2013). Although this might appear to be merely a methodological dispute, it is more complicated than that. Researchers and policymakers working on this case need to evaluate both the quality of the evidence and the most responsible conclusions to draw on the basis of ambiguous evidence. Ultimately, the FDA partnered with the U.S. National Toxicology Program (NTP), the US. National Institute of Environmental Health Sciences (NIEHS), and a number of academic investigators in a project called CLARITY-BPA (Consortium Linking Academic and Regulatory Insights on BPA Toxicity) that was designed to help settle some of these difficult judgments (Schug et al. 2013). They performed a large, collaborative study that followed the regulatory guidelines preferred by the FDA but that also incorporated the new methodologies preferred by a number of academic researchers. Unfortunately, even this massive effort failed to produce results that conclusively settled the issue (Vandenberg et al. 2019; vom Saal and Frederick 2019). Thus, this ongoing conflict illustrates how difficult it is in some cases to distinguish between science that is done well from science that is not. While this might seem to suggest that our norm-based approach is unhelpful, we would argue that it supports our approach. The difficulties involved in distinguishing good science from bad science in a case like this one fit well with our contention that multiple norms need to be considered and that judgment is needed when deciding how to interpret and implement those norms. This case also illustrates how the norms can be specified, debated, and gradually improved. For example, scholars have been working to develop better rules and procedures for evaluating studies in the regulatory context so that the conflicts encountered in the BPA case can be alleviated in the future and regulatory agencies can more easily distinguish studies they can properly rely on from those they cannot (Moermond et al. 2016). Finally, cases like this one illustrate the importance of ongoing philosophical reflection to evaluate the most appropriate aims for science in specific contexts and to determine how best to prioritize norms in ways that achieve those aims (Elliott 2022). Conclusion We have argued that philosophers who are working on what has been called the new demarcation problem, i.e., how to distinguish between legitimate and illegitimate value influences on science, can gain useful insights from the attempts to solve the original demarcation problem, i.e., how to distinguish between science and pseudoscience. An important lesson that philosophers have learned from attempts to solve the original demarcation problem is that it is very difficult to develop necessary and sufficient conditions for drawing a line between science and pseudoscience because science is such a complex and multi-faceted endeavor. Rather, it is more fruitful to characterize science as a family of activities that tend to be guided by a set of shared norms. Given the wide range of contexts in which science is used and the challenges that philosophers have been facing in their efforts to arrive at necessary and sufficient conditions for describing the proper role of external values in science, it seems advisable to adopt an approach to the new demarcation problem that is similar to the response that many philosophers have adopted to the old one. In order to develop an approach of this sort, we have described a set of scientific norms, based on the work of numerous philosophers, historians, sociologists, and scientists, and supplemented them with rules, conventions, policies, and procedures that implement the norms in scientific practice. Admittedly, it will still be challenging in many cases to adjudicate conflicts between the norms, but this is an accurate representation of scientific practice; it is indeed difficult in many cases to decide which value influences are legitimate and which are not. To assist in applying the norms to practical contexts, we have provided a list of questions, and we have shown how our approach can be used for addressing controversial issues in regulatory science. Exploring how to interpret and implement the norms in specific contexts and how to handle conflicts between them is an important topic for future work in the philosophy of science. Funding This research was funded, in part, by the intramural program of the National Institute of Environmental Health Sciences, National Institutes of Health. It does not represent the views of the National Institute of Environmental Health Sciences, National Institutes of Health, or US government. Declarations Conflict of interest The authors have no conflict of interest to declare. 1 We note that some philosophers challenge the distinction between epistemic and non-epistemic values (see e.g., Longino (1990) and Rooney (2017)). While we acknowledge that there is a dispute in the literature about the nature of this distinction, we think it still has considerable merit in some circumstances (see e.g., Steel 2010). There is a significant difference, philosophically, between rejecting a scientific hypothesis because it lacks rigor or empirical support and rejecting it because it conflicts with a particular social or political agenda. 2 The list of critics who convinced some philosophers to reject the value-free ideal is long. Some noteworthy names include Rudner (1953), Kuhn (1962; 1977), Rescher (1965), Barnes (1977), Harding (1986), Latour and Woolgar (1986), Longino (1990), Collins and Pinch (1993). 3 The idea that knowledge must be verifiable predates the twentieth century and is rooted in the works of Hume (1977) and Kant (1996). 4 See Misak (1995) for a review of the history of verificationism. 5 For review, see Mahner (2007), Fasce (2017), Hansson (2017a). 6 It is worth noting that some philosophers have not abandoned the attempt to identify necessary and sufficient conditions for defining science. See Hansson (1996; 2009; 2017b). 7 A key turning point in the evolution of philosophical thinking about the demarcation problem was the publication of Larry Laudan’s (1983) essay “The demise of the demarcation problem,” in which he argued that the only solution one could hope to achieve for this problem is to develop a list of epistemological criteria, such as testability, rigor, reproducibility, empirical adequacy, explanatory power, and precision, which most of the things that we call science have in common. This philosophical move amounted to a dissolution of the demarcation problem as traditionally conceived, rather than a solution (Laudan 1983). 8 For more in-depth discussion, see Douglas (2009; 2016), Steel (2010), Elliott (2017; 2022), Brown (2020). 9 We will focus on philosophical critiques of the value-free ideal in this paper. For sociological critiques, see Barnes (1977), Latour and Woolgar (1986), and Collins and Pinch (1993). For historical critiques, see Kuhn (1962; 1977). 10 In statistics, rejecting a null hypothesis that turns about to be true is known as a Type I error, whereas accepting a null hypothesis that turns out to be false is a Type II error. 11 Quine (1955, 1960) held that theories are always underdetermined by empirical evidence since it is always logically possible to construct alternative theories that account for the evidence just as well as the theories one is considering. Others, such as Laudan and Leplin (1991), acknowledge this point but interpret underdetermination as more of a methodological problem than a logical one because the theories that scientists actually choose between must meet epistemic standards that rule out most logically possible alternatives. 12 Brysse et al. (2013) argue that the IPCC has erred on the side of underestimating risk. 13 Major proponents of axiological approaches typically address this problem by calling for science to jointly satisfy both ethical and epistemic requirements for science (see e.g., Brown 2017; Kourany 2010). 14 de Winter (2016) also distinguishes between direct and indirect value influences in science (see Resnik and Elliott 2019). Since his view is similar to Douglas’, we will not examine it here. 15 In more recent work, Douglas (2021) suggests that a more multi-faceted approach to managing values in science many be needed. 16 We contrast our approach with the approach taken by Elliott and McKaughan (2014), who focus on specific epistemic and practical aims. 17 See Haack (2014) for a critique of the court’s reasoning in Daubert. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Agassi Joseph Popper’s Demarcation of Science Refuted Methodology and Science 1991 24 1 7 Alexandrova Anna Can the Science of Well-Being be Objective? British Journal for the Philosophy of Science 2018 69 421 445 10.1093/bjps/axw027 Anderson Elizabeth Uses of Value Judgments in Science: A General Argument, with Lessons from a Case Study of Feminist Research on Divorce Hypatia 2004 19 1 1 24 10.1111/j.1527-2001.2004.tb01266.x Ayer Alfred J Language, Truth, and Logic 1946 New York, NY Dover Bacon, Francis. 2000 [1620]. Novum Organon. Cambridge, UK: Cambridge University Press. Barnes, Barry. 1977. Interests and the Growth of Knowledge. London, UK: Routledge and Kegan Paul. Betz Gregor In Defence of the Value Free Ideal European Journal of Philosophy of Science 2013 3 207 220 10.1007/s13194-012-0062-x Biddle John State of the Field: Transient Underdetermination and Values in Science Studies in History and Philosophy of Science 2013 44 124 133 10.1016/j.shpsa.2012.09.003 Boorse Christopher Health as a Theoretical Concept Philosophy of Science 1977 44 542 573 10.1086/288768 Boudry Maarten Diagnosing Pseudoscience: By Getting Rid of the Demarcation Problem Journal for General Philosophy of Science 2021 10.1007/s10838-021-09572-4 Bright Liam Du Bois’ Democratic Defence of the Value Free Ideal Synthese 2018 195 2227 2245 10.1007/s11229-017-1333-z Brown Matthew Values in science Beyond Underdetermination and Inductive Risk Philosophy of Science 2013 80 829 839 10.1086/673720 Brown Matthew Elliott Kevin C Steel Daniel Values in Science: Against Epistemic Priority Current Controversies in Values and Science 2017 New York Routledge 64 78 Brown Matthew Science and Moral Imagination: A New Ideal for Values in Science 2020 Pittsburgh University of Pittsburgh Press Brysse Keynyn Oreskes Naomi O’Reilly Jessica Oppenheimer Michael Climate Change Prediction: Erring on the Side of Least Drama? Global Environmental Change 2013 23 1 327 337 10.1016/j.gloenvcha.2012.10.008 Bunge Mario Demarcating Science from Pseudoscience Fundamenta Scientiae 1982 3 369 388 Carnap Rudolph Der Logische Aufbau der Welt 1928 Berlin Welkreis Daubert v. Merrell Dow Pharmaceuticals, Inc. (1993). 509 U.S. 579. Collins Harry Evans Robert Why Democracies Need Science 2017 New York, NY Polity Collins Harry Pinch Robert The Golem: What You Should Know about Science 1993 Cambridge, UK Cambridge University Press Winter De Interests and Epistemic Integrity in Science: A New Framework to Assess Interest Influences in Scientific Research Processes 2016 London Lexington Books Douglas Heather Inductive Risk and Values in Science Philosophy of Science 2000 67 559 579 10.1086/392855 Douglas Heather Maasen Sabine Weingart Peter Inserting the Public Into Science Democratization of Expertise? Exploring Novel Forms of Scientific Advice in Political Decision-Making 2005 Cham, Switzerland Springer 153 169 Douglas Heather Science, Policy, and the Value-Free Ideal 2009 Pittsburgh, PA University of Pittsburgh Press Douglas Heather Humphreys Paul Values in science The Oxford Handbook of Philosophy of Science 2016 New York Oxford University Press 609 632 Douglas, Heather. 2021. The Rightful Place of Science: Values, Science and Democracy (The Descartes Lectures), ed. Ted Richards. Tempe, AZ: Consortium for Science, Policy & Outcomes. Duhem, Pierre. 1914 [1954]. The Aim and Structure of Physical Theory, trans. P. W. Wiener. Princeton, NJ: Princeton University Press. Dupré John The Disorder of Things: Metaphysical Foundations of the Disunity of Science 1993 Cambridge, MA Harvard University Press Dupré John Kincaid Harold Wylie Alison Dupré John Fact and Value Value-Free Science? Ideals and Illusions 2007 New York, NY Oxford University Press 27 41 Elliott Kevin Is a Little Pollution Good for You? Incorporating Societal Values in Environmental Research 2011 New York, NY Oxford University Press Elliott Kevin Standardized Study Designs, Value Judgments, and Financial Conflicts of Interest in Research Perspectives on Science 2016 24 529 551 10.1162/POSC_a_00222 Elliott Kevin A Tapestry of Values: An Introduction to Values in Science 2017 New York, NY Oxford University Press Elliott Kevin The Value-Ladenness of Transparency in Science: Lessons from Lyme Disease Studies in History and Philosophy of Science 2021 88 1 9 10.1016/j.shpsa.2021.03.008 33945897 Elliott Kevin Values in Science 2022 Cambridge Cambridge University Press Elliott Kevin McKaughan Daniel How Values in Scientific Discovery and Pursuit Alter Theory Appraisal Philosophy of Science 2009 76 598 611 10.1086/605807 Elliott Kevin McKaughan Daniel Nonepistemic Values and the Multiple Goals of Science Philosophy of Science 2014 81 1 1 21 10.1086/674345 Elliott Kevin Resnik David B Science, Policy, and the Transparency of Values Environmental Health Perspectives 2014 122 647 650 10.1289/ehp.1408107 24667564 Ereshefsky Marc Defining 'Health' and 'Disease' Studies in the History and Philosophy of Biology and Biomedical Science 2009 40 3 221 227 10.1016/j.shpsc.2009.06.005 Fasce Angelo What Do We Mean When We Speak of Pseudoscience? The Development of Ademarcation Criterion Based on the Analysis of Twenty–One Previous Attempts Disputation: Philosophical Research Bulletin 2017 6 7 459 488 Feuer Lewis S The Paradox of Verifiability Philosophy and Phenomenological Research 1951 12 1 24 41 10.2307/2103366 Food and Drug Administration. 1998. Guidance for Industry: Providing Clinical Evidence of Effectiveness for Human Drug and Biological Products. https://www.fda.gov/media/71655/download. Accessed 28 Feb 2021. Food and Drug Administration. 2018a. What We Do. Available at: https://www.fda.gov/about-fda/what-we-do. Accessed 28 Feb 2021. Food and Drug Administration. 2018b. FDA 101. Available at: https://www.fda.gov/about-fda/what-we-do/fda-101-overview-fdas-regulatory-review-and-research-activities. Accessed 24 June 2019. Food and Drug Administration. 2018c. Bisphenol A (BPA): Use in Food Contact Application. Available at: https://www.fda.gov/food/food-additives-petitions/bisphenol-bpa-use-food-contact-application. Accessed 28 Feb 2021. Frisch Mathias Uncertainties, Values, and Climate Targets Philosophy of Science 2020 87 5 979 990 10.1086/710538 Furberg Bengt D Furberg Curt D Evaluating Clinical Evidence: All that Glitters is not Gold 2008 2 Dordrecht, Netherlands Springer Gallin John Ognibene Frederick Johnson Laura Principles and Practice of Clinical Research 2018 4 London, UK Elsevier Goldenberg Maya Vaccine Hesitancy: Public Trust, Expertise, and the War on Science 2021 Pittsburgh, PA University of Pittsburgh Press Gore Andrea C Editorial: An International Riposte to Naysayers of Endocrine-Disrupting Chemicals Endocrinology 2013 154 3955 3956 10.1210/en.2013-1853 24048096 Gutmann Amy Thompson Dennis Democracy and Disagreement 1998 Cambridge, MA Harvard University Press Haack Susan Defending Science Within Reason 2004 New York, NY Prometheus Books Haack Susan Federal Philosophy of Science: A Deconstruction - and a Reconstruction New York University Journal of Law and Liberty 2014 5 2 394 435 Hansson Sven O Defining Pseudoscience Philosophia Naturalis 1996 33 169 176 Hansson Sven O Cutting the Gordian Knot of Demarcation: What Do We Mean When We Speak of Pseudoscience? International Studies in the Philosophy of Science 2009 23 3 237 243 10.1080/02698590903196007 Hansson, Sven O. 2017a. Science and Pseudoscience. Stanford Encyclopedia of Philosophy. Available at: https://plato.stanford.edu/entries/pseudo-science/. Accessed 25 February 2021. Hansson Sven O Science Denial As a Form of Pseudoscience Studies in History and Philosophy of Science Part A 2017 63 39 47 10.1016/j.shpsa.2017.05.002 Harding Sandra The Science Question in Feminism 1986 Ithaca, NY Cornell University Press Hempel Carl Aspects of Scientific Explanation 1965 New York, NY Free Press Hicks Daniel J A New Direction for Science and Values Synthese 2014 191 3271 3295 10.1007/s11229-014-0447-9 Holman Bennett Bruner Justin Experimentation by Industrial Selection Philosophy of Science 2017 84 1008 1019 10.1086/694037 Holman Bennett Elliott Kevin The Promise and Perils of Industry-Funded Science Philosophy Compass 2018 13 e12544 10.1111/phc3.12544 Holman Bennett Wilholt Torsten The New Demarcation Problem Studies in the History and Philosophy of Science 2022 91 211 220 10.1016/j.shpsa.2021.11.011 Hudson Robert Why We Should Not Reject the Value-Free Ideal for Science Perspectives on Science 2016 24 2 167 191 10.1162/POSC_a_00199 Hull David Science as a Process 1990 Chicago, IL University of Chicago Press Hume, David. 1748 [1977]. An Enquiry Concerning Human Understanding. ed. Eric Steinberg. Indianapolis, IN: Hackett. Jeffrey Richard Valuation and the Acceptance of Scientific Hypotheses Philosophy of Science 1956 23 3 237 246 10.1086/287489 John Stephen Inductive Risk and the Contexts of Communication Synthese 2015 192 79 86 10.1007/s11229-014-0554-7 Intemann Kristen Distinguishing Between Legitimate and Illegitimate Values in Climate Modeling European Journal of Philosophy of Science 2015 5 217 232 10.1007/s13194-014-0105-6 Intemann Kristen Elliot Kevin Steel Daniel Feminism, Values, and the Bias Paradox: Why Value Management is Not Sufficient Current Controversies in Values and Science 2017 New York, NY Routledge 130 144 Intergovernmental Panel on Climate Change Climate Change 2014: Mitigation of Climate Change 2014 Cambridge, UK Cambridge University Press Jasanoff Sheila The Fifth Branch: Science Advisors as Policymakers 1998 Cambridge, MA Harvard University Press Kant, Immanuel. 1781 [1996]. Critique of Pure Reason, Werner Pluhar (transl.). Indianapolis, IN: Hackett. Kitcher Philip Abusing Science 1983 Cambridge, MA MIT Press Kitcher Philip The Advancement of Science 1993 New York, NY Oxford University Press Kitcher Philip Science, Truth, and Democracy 2001 New York, NY Oxford University Press Kitcher Philip Science in a Democratic Society 2011 New York, NY Oxford University Press Koskinen Inkeri Rolin Kristina Distinguishing Between Legitimate and Illegitimate Roles for Values in Transdisciplinary Research Studies in the History and Philosophy of Science 2022 91 191 198 10.1016/j.shpsa.2021.12.001 Kourany Janet Philosophy of Science after Feminism 2010 New York, NY Oxford University Press Krimsky Sheldon Science in the Private Interest: Has the Lure of Profits Corrupted Biomedical Research? 2003 Lanham, MD Rowman and Littlefield Kuhn Thomas The Structure of Scientific Revolutions 1962 Chicago University of Chicago Press Kuhn Thomas The Essential Tension 1977 Chicago, IL University Chicago Press Lacey Hugh Is Science Value-Free? Values and Scientific Understanding 1999 New York, NY Routledge Lacey Hugh Elliott K Steel D Distinguishing Between Cognitive and Social Values Current Controversies in Values and Science 2017 New York Routledge 15 30 Lakatos Imre Lakatos Imre Musgrave Alan Falsificationism and the Methodology of Scientific Research Programmes Criticism and the Growth of Knowledge 1970 Cambridge, UK Cambridge University Press 91 196 Larson Brendon Metaphors for Environmental Sustainability: Redefining our Relationships with Nature 2011 New Haven, CT Yale University Press Latour Bruno Woolgar Steven Laboratory Life: The Social Construction of Scientific Facts 1986 Princeton, NJ Princeton University Press Laudan Larry Progress and its Problems 1977 Berkeley, CA University of California Press Laudan Larry Cohen Robert S Laudan Larry The Demise of the Demarcation Problem Physics, Philosophy, and Psychoanalysis 1983 Dordrecht, Netherlands Reidel 111 127 Laudan Larry Science and Values: The Aims of Science and Their Role in Scientific Debate 1984 Pittsburgh, PA University of Pittsburgh Press Laudan Larry Leplin Jarrett Empirical Equivalence and Underdetermination Journal of Philosophy 1991 88 449 472 10.2307/2026601 Lexchin Joel Those Who Have the Gold Make the Evidence: How the Pharmaceutical Industry Biases the Outcomes of Clinical Trials of Medications Science and Engineering Ethics 2012 18 2 247 261 10.1007/s11948-011-9265-3 21327723 London Alex John For the Common Good: Philosophical Foundations of Research Ethics 2022 Oxford, UK Oxford University Press Longino Helen Science as Social Knowledge 1990 Princeton, NJ Princeton University Press Magee Bryan Popper 1985 New York, NY Harper Collins Lusk Greg Elliott Kevin C Non-epistemic Values and Scientific Assessment: An Adequacy-for-Purpose View European Journal for Philosophy of Science 2022 12 35 10.1007/s13194-022-00458-w Mahner Martin Kuipers Theo Demarcating Science from non-Science General Philosophy of Science: Focal Issues 2007 Amsterdam Elsevier 515 575 Mann Michael E The New Climate War: The Fight to Take Back Our Planet 2021 New York, NY Hachette Book Group Mantzavinos Chrysostomos Science, Institutions, and Values European Journal of Philosophy 2020 10.1111/ejop.12579 McGarity Thomas O Wagner Wendy E Bending Science: How Special Interests Corrupt Public Health Research 2008 Cambridge, MA Harvard University Press Merton Robert The Sociology of Science 1973 Chicago, IL University of Chicago Press Michaels David Doubt is Their Product: How Industry’s Assault on Science Threatens Your Health 2008 New York, NY Oxford University Press Misak, Cheryl. 1995. Verificationism: Its History and Prospects. New York. NY: Routledge. Moermond Caroline T Kase Robert Korkaric Muris CRED: Criteria for Reporting and Evaluating Ecotoxicity Data Environmental Toxicology and Chemistry 2016 35 1297 1309 10.1002/etc.3259 26399705 Nagel Ernst The Structure of Science 1961 New York, NY Harcourt, Brace, and World Myers John P vom Saal Frederick S Akingbemi Benson T Why Public Health Agencies Cannot Depend on Good Laboratory Practices As a Criterion for Selecting Data: The Case of Bisphenol A Environmental Health Perspectives 2009 117 309 315 10.1289/ehp.0800173 19337501 Oreskes, Naomi and Erik M. Conway. 2010. Merchants of Doubt. New York: NY: Bloosmbury. Parker Wendy Lusk Greg Incorporating User Values into Climate Services Bulletin of the American Meteorological Society 2019 100 1643 1650 10.1175/BAMS-D-17-0325.1 Pielke Robert The Honest Broker: Making Sense of Science in Policy and Politics 2007 Cambridge, UK Cambridge University Press Pigliucci Massimo Boudry Maarten Philosophy of Pseudoscience: Reconsidering the Demarcation Problem 2013 Chicago, IL University of Chicago Press Popper Karl The Logic of Scientific Discovery 1959 London Hutchinson Popper Karl Conjectures and Refutations 1963 New York, NY Harper and Row Quine Willard V.O. Two Dogmas of Empiricism The Philosophical Review 1951 60 1 20 43 10.2307/2181906 Quine Willard V.O. From a Logical Point of View 1953 Cambridge, MA Harvard University Press Quine Willard V.O. The Ways of Paradox and Other Essays 1955 2 Cambridge, MA Harvard University Press Quine Willard V.O. Word and Object 1960 Cambridge, MA MIT Press Quine Willard V.O. Ullian Joseph The Web of Belief 1974 New York, NY McGraw-Hill Reichenbach Hans Experience and Prediction 1938 Chicago, IL University of Chicago Press Rescher, Nicholas. 1965. The Ethical Dimensions of Scientific Research. In: Beyond the Edge of Certainty: Essays on Contemporary Science and Philosophy, ed. Nicholas Rescher, pp. 261–276. Englewood Cliffs, NJ: Prentice-Hall, Englewood Cliffs. Resnik David B Social Epistemology and the Ethics of Research Studies in the History and Philosophy of Science 1996 27 4 566 586 10.1016/0039-3681(96)00043-X Resnik David B The Ethics of Science 1998 New York, NY Routledge Resnik David B A Pragmatic Approach to the Demarcation Problem Studies in the History and Philosophy of Science 2000 31 249 267 10.1016/S0039-3681(00)00004-2 Resnik David B The Price of Truth: How Money Affects the Norms of Science 2007 New York, NY Oxford University Press Resnik David B Playing Politics with Science: Balancing Scientific Independence and Government Oversight 2009 New York, NY Oxford University Press Resnik David B Scientific Research and the Public Trust Science and Engineering Ethics 2011 17 399 409 10.1007/s11948-010-9210-x 20803259 Resnik David B Retracting Inconclusive Research: Lessons from the Séralini GM Maize Feeding Study Journal of Agricultural and Environmental Ethics 2015 28 621 633 10.1007/s10806-015-9546-y 26251636 Resnik David B Elliott Kevin C Bisphenol A and Risk Management Ethics Bioethics 2015 29 182 189 10.1111/bioe.12079 24471646 Resnik David B Elliott Kevin C Value-Entanglement and the Integrity of Scientific Research Studies in History and Philosophy of Science 2019 75 1 11 10.1016/j.shpsa.2018.12.011 Ritchie Stuart Science Fictions: Exposing Fraud, Bias, Negligence and Hype in Science 2020 New York, NY Metropolitan Books Roewer Lutz DNA Fingerprinting in Forensics: Past, Present, Future Investigative Genetics 2013 4 22 10.1186/2041-2223-4-22 24245688 Rolin Kristina Values in Science: The Case of Scientific Collaboration Philosophy of Science 2015 82 157 177 10.1086/680522 Rooney Phyllis Elliott Kevin C Steel Daniel The Borderlands Between Epistemic and External Values Current Controversies in Values and Science 2017 New York, NY Routledge 31 45 Rosenberg Alexander Philosophy of Social Science 2015 5 New York, NY Routledge Rothstein Paul F Raeder Myrna S Crump David Evidence 2011 6 St. Paul, MN West Publishing Rudner Richard The scientist qua scientist makes value judgments Philosophy of Science 1953 20 1 1 6 10.1086/287231 Ruse Michael But is it Science? The Philosophical Question in the Creation/Evolution Controversy 1996 Amherst, NY Prometheus Books Saphier Natalie Panic Attack: Playing Politics with Science in the Fight Against COVID-19 2021 New York, NY Broadside Books Schaffner Kenneth Discovery and Explanation in Biology and Medicine 1993 Chicago, IL University of Chicago Press Schlosberg David Defining Environmental Justice: Theories, Movements, and Nature 2009 New York, NY Oxford University Press Schroeder, S. Andrew. 2017. Using Democratic Values in Science: An Objection and Partial Response. Philosophy of Science 84: 1044–1054. Schug Thaddeus T Heindel Jerrold J Camacho Luísa A New Approach to Synergize Academic and Guideline-Compliant Research: The CLARITY-BPA Research Program Reproductive Toxicology 2013 40 35 40 10.1016/j.reprotox.2013.05.010 23747832 Sellars, Wilfrid. 1956. Empiricism and the Philosophy of Mind. In: Minnesota Studies in the Philosophy of Science, Vol. 1, ed. Herbert Feigl and Michael Scriven, 253–329. Minneapolis, MN: University of Minnesota Press. Shamoo Adil E Resnik David B Responsible Conduct of Research 2022 4 New York, NY Oxford University Press Sismondo Sergio Pharmaceutical Company Funding and Its Consequences: A Qualitative Systematic Review Contemporary Clinical Trials 2008 29 2 109 113 10.1016/j.cct.2007.08.001 17919992 Steel Daniel Epistemic Values and the Argument from Inductive Risk Philosophy of Science 2010 77 1 14 34 10.1086/650206 Steel Daniel Philosophy and the Precautionary Principle: Science, Evidence, and Environmental Policy 2015 Cambridge, UK Cambridge University Press Steel Daniel Elliott Kevin C Steel Daniel Qualified Epistemic Priority: Comparing Two Approaches to Values in Science Current Controversies in Values and Science 2017 New York Routledge 49 63 Steel Daniel Whyte Kyle P Environmental Justice, Values, and Scientific Expertise Kennedy Institute of Ethics Journal 2012 22 163 182 10.1353/ken.2012.0010 23002582 Straus Sharon E Glasziou Paul Scott Richardson W Evidence-Based Medicine: How to Practice and Teach 2019 5 Amsterdam Elsevier Thagard, Paul. 1978. Why Astrology is a Pseudoscience. In: Proceedings of the Philosophy of Science Association, vol. 1., ed. Peter Asquith and Ian Hacking pp. 223–224. East Lansing, MI: Philosophy of Science Association. Thagard Paul Computational Philosophy of Science 1988 Cambridge, MA MIT Press Vandenberg Laura N Hunt Patricia A Gore Andrea C Endocrine Disruptors and the Future of Toxicology Testing—Lessons from CLARITY–BPA Nature Reviews Endocrinology 2019 15 366 374 10.1038/s41574-019-0173-y Vandenberg Laura N Prins Gail S Clarity in the Face of Confusion: New Studies Tip the Scales on Bisphenol A (BPA) Andrology 2016 4 561 10.1111/andr.12219 27189146 vom Saal Frederick S Flaws in Design, Execution and Interpretation Limit CLARITY-BPA’s Value for Risk Assessments of Bisphenol A Basic & Clinical Pharmacology & Toxicology 2019 125 32 43 10.1111/bcpt.13195 30589220 Wagner Wendy Steinzor Rita Rescuing Science from Politics 2006 Cambridge, UK Cambridge University Press Wilholt Torsten Bias and Values in Scientific Research Studies in History and Philosophy of Science 2009 40 92 101 10.1016/j.shpsa.2008.12.005 Wittgenstein, Ludwig. 1973 [1953]. Philosophical Investigations. Transl. Gertrude E.M. Anscombe. New York, NY: Pearson. Ziman John Real Science: What It is and What It Means 2000 Cambridge Cambridge University Press
PMC009xxxxxx/PMC9957686.txt	==== Front Clin Oral Investig Clin Oral Investig Clinical Oral Investigations 1432-6981 1436-3771 Springer Berlin Heidelberg Berlin/Heidelberg 36829064 4921 10.1007/s00784-023-04921-7 Research Impact of the use of dental services on dental pain according to adolescents’ skin colour: a 10-year cohort Rauber Everton Daniel [email protected] 1 Knorst Jessica Klöckner [email protected] 2 Noronha Thaís Gioda 1 Zemolin Nicole Adrielli Monteiro 1 Ardenghi Thiago Machado [email protected] 34 1 grid.411239.c 0000 0001 2284 6531 Postgraduate Program in Dental Sciences, Federal University of Santa Maria, Rua Conde de Porto Alegre, Santa Maria, RS 961 Brazil 2 grid.411239.c 0000 0001 2284 6531 Postgraduate Program in Dental Sciences, Federal University of Santa Maria, Rua Venâncio Aires, Santa Maria, RS 1434 Brazil 3 grid.411239.c 0000 0001 2284 6531 Departament of Stomatology, School of Dentistry, Federal University of Santa Maria, Santa Maria, Brazil 4 grid.411239.c 0000 0001 2284 6531 Universidade Federal de Santa Maria, Roraima nº 1000 Bairro Camobi, CEP: 97105900, Santa Maria, RS Brazil 25 2 2023 2023 27 6 31493157 3 11 2022 13 2 2023 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Objective Evaluate the association of the interaction between the use of dental services and the skin colour on the occurrence of dental pain over time. Material and methods This study is a cohort with 10 years of follow-up, started in 2010 with a sample of 639 preschool children (1–5 years old). The use of dental services, race and the presence of dental pain were self-reported by the individuals according to predefined criteria. Multilevel logistic regression analysis was performed to assess the interaction between skin colour and use of dental services in the occurrence of dental pain over time. Results About 449 and 429 were reassessed in 2017 and 2020, respectively. The occurrence of dental pain across the cohort was 60.7%. Caucasian individuals who used dental services throughout the cohort had a 51% lower chance of having a dental pain than those who used dental services but were non-white (OR 0.49; 95% IC 0.27–0.90). Conclusion There was a racial inequity in the occurrence of dental pain among individuals who managed to make use of dental services throughout the follow-ups. Clinical relevance The differences found should serve as a warning to the way how individuals with different characteristics are treated and must be used to combat this inequity. Individuals should receive resolute and personalized treatments according to their clinical condition and not according to their socioeconomic characteristics. Keywords Adolescence Longitudinal study Oral health Dental care Race factors Dental pain issue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction Oral diseases remained highly prevalent around the world and affect populations unevenly, being more concentrated in socially disadvantaged groups [1–4]. Furthermore, the global burden of oral diseases impacts high economic costs [5], especially in countries with lower socioeconomic backgrounds [6–9], as well as in the daily life and well-being of the affected individuals [10]. Thus, the effects of socioeconomic, demographic and behavioural characteristics on oral health have been previously explored [10–14]. Among these factors is the use of dental services, which have been considered an important indicator of levels of oral health in children and adults [13, 15]. In Brazil, the prevalence of use of dental services in the last year is around 40% when considering the age group of children [16]. In relation to the pattern of use, it was found that only 35% of these use dental services for routine or preventive reasons. In addition, about 50% of individuals in childhood and adolescence tend to use the public health system, especially those belonging to lower-income groups [16]. Previous studies have shown that individuals who seek the service for preventive reasons, or that lived in neighbourhoods that have dentists in public services, were more likely to present better oral health outcomes [13, 17]. Furthermore, it has been demonstrated that non-white individuals have worse oral health status and lower rates of use of dental services compared to their counterparts [18–20]. Race has been considered a structural health determinant [21] which influences psychosocial, behavioural and biological factors, leading to poorer oral health, and also has been related to work relationships, educational levels and income [22], which may impact individuals’ behaviours and knowledge in relation to their oral health [23]. Among the oral health outcomes affected by sociodemographic and behavioural conditions is the dental pain, which has been explored in studies considering different populations [23–26]. Pain can be defined as an unpleasant symptom and emotional experience caused by tissue damage [27, 28]. Dental pain has been reported as the most frequent type of orofacial pain and can affect social interaction and daily activities, and negatively impact the oral health-related quality of life (OHRQoL) [27, 29–32]. Therefore, dental pain can be considered a multifactorial health problem and an important outcome to be considered, especially during infancy and adolescence, a period of important biopsychosocial changes. Although some previous studies have evaluated the impact of the use of services and ethnicity on dental pain occurrence, the impact of the use/reason for dental service on dental pain according to the individual’s skin colour has not yet been explored [33, 34]. Studying the effect of the interaction between these variables is important when assessing inequalities in oral health outcomes and could be useful for public health planning and prevention of oral health diseases. Thus, this study aimed to evaluate the impact of the use of dental services and the reason for dental attendance in the report of dental pain according to the skin colour of the adolescents. Our conceptual hypothesis is that non-white individuals who have used the dental services over the years, and whose reason was for preventive treatments, were more likely to have dental pain than white individuals with the same pattern of use. Material and methods Study design This is a prospective cohort study with 10 years of follow-up. This project involved the baseline and 3 follow-up evaluations in the years 2012 (2 years), 2017 (7 years) and 2020 (10 years). The present study considered baseline data in 2010 (T1) and follow-up data in 2017 (T2) and 2020 (T3). This study was approved by the Research Ethics Committee of the Federal University of Santa Maria (CAAE 54257216.1.0000.5346). Data were only collected after the parents/guardians of the participants consented and signed the informed consent form. Baseline assessment The baseline evaluation was carried out in 2010, during the National Children’s Vaccination Day in the city of Santa Maria, southern Brazil. The estimated population of the city in 2010 was 263,403 inhabitants, which included 27,520 children under 6 years old. Data collection began with an epidemiological survey of oral health, where a random sample of 639 preschool children aged 1 to 5 years was evaluated. The sampling points were 15 basic health centres that contained a dental chair, well distributed in the 8 administrative regions of the city. These health centres were the largest in the city and covered around 85% of the children in the city. At the time of collection, children were systematically selected, for every 5 positions in the queue. Individuals with some cognitive impairments were not considered eligible (Fig. 1).Fig. 1 Flowchart of the three data collection periods To calculate the sample size, we considered a standard error of 5%, a confidence level of 95% and a prevalence of dental pain of 7.59% in the exposed group (individuals who did not use the dental service) and 18.05% in the unexposed group (individuals who used the dental service) [28]. The calculation considered an exposed to the non-exposed ratio of 1:1 and a statistical power of 80%. In addition, the design effect of 1.2 was considered to increase accuracy due to multistage sampling. The minimum sample size was determined at 377 children, to which 30% was added to compensate for possible losses in follow-up, resulting in an initial sample of 490 pre-schoolers aged 1 to 5 years. Follow-up assessments Data collection from 7 years of follow-up was carried out during the year 2017, and considered all children evaluated at baseline (n=639). These individuals, who at that time were aged between 8 and 12 years, were again invited to participate in the evaluations. Other details and the results of the second phase of the study have already been published [35, 36]. Posteriorly, individuals were evaluated between 2019 and 2021, totalling 10 years of follow-up. In this moment, the individuals were between 11 and 15 years old and were already considered adolescents. Due to the COVID-19 pandemic, these data collection procedures were suspended in March 2020 and recaptured in October of the same year. Other details and the results of the second phase of the study have already been published [37]. In both follow-up periods, children were sought and re-evaluated at their respective schools or during home visits. The personal data was constantly updated through phone calls or social networks, such as WhatsApp or Facebook. In the same way as in the previous stage, the children were located and invited, together with their families, to participate in the new cohort wave. Evaluated measures The outcome variable, dental pain, was subjectively collected at T2 and T3 through the following question: “Has your child ever had an episode of dental pain?” and, if the answer was positive, the time elapsed since the last occurrence was questioned from the options “less than 6 months”, “6 months to 1 year” and “more than 1 year”. This approach has already been used in previous studies [29, 30, 38]. For data analysis, it was considered whether the individual presented any dental pain episodes at T2 and/or T3 (0= not; 1= yes). The behaviour of individuals in relation to the use of dental services and the reason for the last dental appointment were investigated at T1, T2 and T3. Regarding the use of dental services, the following question was asked to those caregivers: “Has your child used any dental service during the last year?”, with the answer options “yes” or “no”. This question has already been used in previous studies [13, 35]. For data analysis, the use of dental services throughout the cohort assessment periods was considered (0= not; 1= yes). The reasons for the last dental appointment were the following: 1= restorative issues; 2= extractions (due to dental caries), 3= urgent treatments or 4= preventive treatments (hygiene guidance, diagnosis, orthodontic treatment). For analysis purposes, the reason for the last dental appointment was dichotomized into routine (4) and non-routine (1, 2 and 3). For the longitudinal data analysis, the children were classified according to the trajectory for the reason for dental appointments as the following: 0= routine use (always for routine reasons or that change from non-routine to routine throughout the cohort-improvement) and 1= non-routine use (always for non-routine/treatment reasons, or that change from routine for non-routine throughout the cohort—worsening) [13]. Skin colours were collected at baseline according to the criteria established by the Brazilian Institute of Geography and Statistics (IBGE), which is performed in population-based surveys [39] using the following question: “What race do you consider your child to be?”, with the response options: 1= “white”, 2= “brown”, 3= “black”, 4= “yellow” or 5= “indigenous”. For data analysis, skin colour was dichotomized as whites (0) or non-whites (2, 3, 4 and 5). This approach has already been used in previous studies that collected this variable [12, 17] since southern Brazil presented few inhabitants with delicate skin colours such as brown, yellow or indigenous [22], generating very low frequencies in these categories. Sex (boys and girls), age (in years), household income and dental caries were measured as possible confounders. Household income was collected as the mean monthly family income in Reais (Brazilian currency—US $1.00 is equivalent to R$5, approximately) and categorized into income quartiles. For the oral examination regarding the presence of dental caries, the International Caries Detection and Assessment System was used (ICDAS) [40]. Data regarding the children’s oral conditions were obtained through clinical examinations carried out in health centres at baseline or in the schools or homes at follow-ups. During data collection, all examiners were previously trained and calibrated (inter- and intra-examiner kappa coefficients ranged from 0.70 to 0.96), and conducted clinical examinations with the aid of gauze, CPI probe and a clinical mirror [41]. For data analysis, dental caries was considered according to the number of teeth with the presence of cavitated lesions (ICDAS code 3, 5 or 6). The ICDAS code 4 was not considered, as in previous studies with this same sample and, to maintain the consistency with these previous studies, the same approach was maintained [13, 30]. Data analysis Data were analysed using the statistical program STATA 14.0 (Stata Corporation, College Station, TX, USA). A descriptive analysis was performed to evaluate the characteristics of the sample, considering the sample weight (“svy” command). The comparison between followed and dropouts’ individuals over time, as well as those evaluated before and during the COVID-19 pandemic, was performed using the t-test (quantitative variables) and the chi-square test (qualitative variables). The study outcome was the occurrence of episodes of dental pain in 2017 and 2020. Multilevel logistic regression models were used to assess the interaction between variables regarding the use of dental services and skin colour in the report of dental pain over time. Moderation effects occur when the relationship between two variables is modified according to a third variable [42]. Our data were tested on a scale of multiplicative interactions, as in previous studies [37, 43]. The multilevel structure of analysis considered individuals (level 1) nested in the 15 neighbourhoods (level 2). A fixed-effect model with random intercept was used. Unadjusted analysis assessed the association between dental pain, skin colour and possible confounders (i.e. age, household income and dental caries). Variables that presented p<0.20 in the unadjusted analysis were included in adjusted models. Results are presented in odds ratio (OR) and 95% confidence intervals (95% CI). Results Of the 639 children assessed at baseline, 449 were followed in 2017 (70.3% response rate) and 429 were reassessed in 2020 (67.1% response rate). The dropouts were due to not locating the individuals and refusal. There was no difference in sample characteristics between individuals who were followed and dropouts, nor between those evaluated before and after the COVID-19 pandemic (p>0.05). Table 1 displays the characteristics of the sample throughout the cohort for children followed for 10 years. Of the children re-examined, 52% were girls and 51.5% were non-white. The mean age at 10-year follow-up was 12.6 years (standard error 0.1). The percentage of children with at least one cavitated caries lesion was 30.6%. Approximately 56.9% of individuals did not use dental services and 11.5% presented a poor trajectory regarding the reason for using dental services. The prevalence of dental pain during follow-ups was 60.7%.Table 1 Characteristics of the sample throughout the cohort for children followed for 10 years (n=429) Variables N (%) p-value Demographic and socioeconomic variables Sex 0.227 Boys 209 (48.0) Girls 220 (52.0) Age (mean [SE]) 12.6 (0.1) 0.05 Skin colour 0.158 White 215 (48.5) Non-white 211 (51.5) Household income quartiles in Reals (R$) 0.300 Quartile 1, lowest 110 (25.6) Quartile 2 79 (18.4) Quartile 3 108 (25.2) Quartile 4, highest 77 (17.9) Behavioural variable Use of dental services in the last year - Yes 179 (43.1) Not 250 (56.9) Reason for dental attendance - Routine 322 (88.5) Not routine 42 (11.5) Oral health variables Dental pain - Absent 162 (39.2) Present 250 (60.7) Untreated dental caries 0.774 Absent 300 (69.4) Present 129 (30.6) SE, standard error; R$, Brazilian Real (US $1.00 is equivalent to R$ 5.4 approximately) Taking into account the sampling weight; values lower than 429 are due to missing data. P-value refers to the comparison between participants in the follow-up and dropouts, and between individuals evaluated before and during the COVID-19 pandemic Descriptive analyses of the use of dental services according to skin colour are presented in Table 2. Among the individuals who used the dental service, 76.6% had white skin colour and 23.4% were non-white. Regarding the trajectory of dental attendance, 23.8% of non-white individuals had a non-routine use trajectory over time.Table 2 Descriptive analysis of the use of dental services according to skin colour Variables Skin colour N (%)* White Non-white p-value Use of dental service in the last year 0.688 Yes 305 (97.1) 93 (97.9) Not 9 (2.9) 2 (2.1) Reason for dental attendance 0.905 Routine 248 (88.5) 74 (88.1) Not routine 32 (11.5) 10 (11.9) Taking into account the sampling weight. Values lower than 429 are due to missing data Unadjusted analysis between the use of dental services, skin colour and dental pain is presented in Table 3. A significant association was found between the interaction of the variables use of services and skin colour and dental pain during the follow-ups (p < 0.05).Table 3 Unadjusted analysis of the predictor variables and interaction of skin colour and use of dental service in the last year on dental pain throughout 10 years cohort Variables Dental pain OR (95% CI) p-value Skin colour#use of dental service in the last year Non-white#yes 1 White#yes 0.51 (0.31–0.85) 0.010 White#not 1.30 (0.25–6.77) 0.754 Non-white#not 0.36 (0.20–6.13) 0.477 Skin colour#reason for dental attendance Non-white#routine 1 White#routine 0.47 (0.26–0.85) 0.014 White#not routine 0.30 (0.12–0.73) 0.008 Non-white#not routine 0.32 (0.08–1.25) 0.102 OR, odds ratio; CI, confidence interval; #, interaction among variables Table 4 shows that among those who have used the dental service over the follow-up periods, white individuals presented a 46% lower chance of experiencing dental pain (OR 0.54; 95% CI 0.32–0.93) than non-white individuals. Considering the reasons for dental attendance, white individuals who presented both routine and non-routine trajectory of use of dental service had 52% (OR 0.48; 95% CI 0.25–0.91) and 76% (OR 0.24; 95% CI 0.09–0.63) lower chances of having dental pain than non-white individuals who had a routine trajectory of using dental services.Table 4 Adjusted analysis of the predictor variables and interaction of skin colour and use of dental services on dental pain throughout the 10 years of cohort Variables Dental pain OR (95% CI) p-value Skin colour#use of dental service in the last year Non-white#yes 1 White#yes 0.54 (0.32–0.93) 0.028 White#not 1.51 (0.28–8.10) 0.627 Non-white#not 0.33 (0.01–5.84) 0.456 Skin colour#reason for dental attendance Non-white#routine 1 White#routine 0.48 (0.25–0.91) 0.026 White#not routine 0.24 (0.09–0.63) 0.004 Non-white#not routine 0.23 (0.05–1.01) 0.053 OR, odds ratio; CI, confidence interval; #, interaction among variables *Adjusted by sex, household income and untreated dental caries Discussion This study aimed to evaluate the impact of the use of dental services on dental pain according to skin colour among adolescents. Our findings confirm the conceptual hypothesis that non-white individuals who used dental services over time or that used the service for preventive reasons were more likely to present dental pain over time than white individuals with the same pattern of use. These results reinforce the idea that there are differences in dental attendance between white and non-white individuals. Our findings evidenced a disparity in the odds of occurrence of dental pain among individuals of different skin colour who have used dental services at least once during the 10-year follow-up period. Non-white individuals were more likely to have dental pain, even when compared with white individuals who used dental services at least once over time. These results agree with some published studies that report a higher prevalence of dental pain among individuals declared to be non-white, regardless of other factors [44–46]. In this sense, we observed a racial inequity in solving the occurrence of dental pain from using dental services. A possible explanation for this finding is that professionals plan, execute and indicate different treatments according to skin colour, as shown in previous studies [20, 47, 48]. This approach disfavours those belonging to the non-white portion of the population and justifies the finding that, even after undergoing a dental appointment, non-white individuals presented more dental pain than their counterparts [20, 47, 48]. Considering the reason for the last dental appointment, our results showed that non-white individuals who have used the service for routine reasons over time were more likely to present dental pain than white individuals with the same pattern of use. This finding confirms the information previously discussed regarding the inequities in dental treatment according to skin colour, which may impact oral health outcomes, such as dental pain [13, 20, 49, 50]. These results have proven important and answer the research question. In addition, when considering not only the use of dental services but also the way in which the services are used, individuals with non-white skin colour are still more likely to have dental pain over time relative to their comparators. This finding highlights the potential of the “skin colour” variable to influence the occurrence of dental pain. Comparing our findings with those found in previous studies, it is possible to observe that the prevalence of use of dental services in our sample was higher, in both whites (97.1%) and non-whites (97.9%). Some authors report a prevalence of use of 59.8% for white individuals and 44.1% for non-white individuals in similar age groups [51]. Another study, when investigating the prevalence of use among adolescents, found that 58.4% of those evaluated reported having had at least one dental appointment in the last year [52]. This high rate in our study is due to the way the variable was categorized, comprising the use of service in all cohort waves. This result is in line with data from another study that collected this variable in adolescents from the question “have you ever had a dentist appointment in your life?”, and pointed to a prevalence of positive responses in 90.9% of respondents [49]. Debating the reason for the last dental appointment, a study shows that 61.1% of adolescents sought dental services for non-preventive reasons. Other surveys in a similar age group showed that less than half of the individuals reported seeking dental care for preventive reasons, revealing the curative character that dentistry still has at national and international levels [49, 53]. In comparison, our study showed that 88.5% of the individuals always used it for a preventive reason or have gone for preventive reasons during the follow-up to do so over time. The possible explanation for this high level of individuals using the services in a preventive way is given by the way in which the variable was treated, since it always considered the last consultations prior to the data collection stages, not taking into account possible non-preventive appointments between the periods. In addition, considering the trajectory of the form of use, individuals who initially used it in a curative way and started to do so in a preventive way over time were also part of the allocated portion in the “routine” group. Regarding dental pain, our study showed a total prevalence of 60.7% in the follow-ups (T2 and T3). A previous systematic review presented occurrences of dental pain from 1.33 to 87.8% among individuals of similar age groups, reinforcing that the prevalence tends to vary according to the different methodologies used in the data gathering [54]. When comparing with another study with a similar age group and methodology developed in Brazil, our study showed a significantly higher prevalence of dental pain, and these differences can be explained due to the subjective nature of the variable and by the report by the parents or guardians [55]. It is also important to discuss the close relationship between skin colour, used as a predictor for the outcome of the study, and household income, also collected during the follow-up period. The literature has extensively shown that this relationship is consistent [22, 46, 56, 57]. Previous studies have demonstrated that white individuals, both in Brazil and in other countries, are responsible for the highest concentrations of income in their families. On the other hand, those individuals who self-declared as having black skin colour or other “non-white” categories have a greater chance of belonging to families with a lower household income [22, 56]. When evaluated as predictors for the occurrence of dental pain in studies with similar populations, both income and skin colour have been considered important predictors, with individuals with lower income and non-white skin colour being more affected by dental pain [46, 57]. These facts may potentiate the occurrence of dental pain in individuals with non-white skin colour since this class is related to lower income and both characteristics increase the chances of occurrence of the outcome. This study has some limitations: it is possible that a selection bias arouses since some individuals were evaluated at T3 before and others during the COVID-19 pandemic. It may also have introduced a response bias regarding some behavioural factors, as well as in the occurrence of dental caries since it has demonstrated the impact of the COVID-19 pandemic on oral health in this age group [58]. However, sensitivity analysis showed that this concern might not affect our findings. Furthermore, the measures regarding the use of dental services and dental pain were self-reported by participants’ parents or guardians, which may be subject to information bias. In this epidemiological study, skin colour, one of the main predictors, was broadly collected, as recommended by the Brazilian Institute of Geography and Statistics (IBGE) [39]. However, for data analysis, the variable was dichotomized into white and non-white individuals. This approach can limit the findings since it compiles individuals with different characteristics into the same group. Thus, possible differences among the categories grouped as non-whites may not have been explored deeply, since yellow, indigenous and especially brown and black people may have distinct realities, although both groups present poorer socioeconomic characteristics than white individuals [59]. Notwithstanding, despite emphasizing the importance of better differentiating groups, our categorization into whites and non-whites was due to the low frequency of individuals who self-declared as brown, yellow or indigenous. Another limitation of the study is the fact that we did not consider carious lesions with the ICDAS code 4, as performed in previous studies using the same sample [13, 30], which may decrease the detection of dental caries during clinical examinations. Among the potential of the study, this is a longitudinal study with a long follow-up period and non-significant losses over time, as well as presented good response rates through the evaluation periods. In addition, the monitoring of a sample from early childhood to adolescence is of paramount importance since that provides relevant data regarding structural, behavioural and subjective variables collected during a biopsychosocial period, which can generate impacts during adulthood and persist during the years. Thus, studying these aspects during adolescence, a transitional phase characterized by a time of intense physical, psychological, affective and behavioural changes, is essential in order to provide evidence of the factors that affect this age group in general and specific groups, as belonging to the same socioeconomic class or with similar behaviours. These data can be of great value for health planning for these populations and should guide policies aimed at reducing inequalities in oral health. Our findings concluded that among individuals who used the dental service, those who were of non-white skin colour were more likely to present dental pain, even if the reason for using the dental service was for routine preventive treatments. These findings reinforce the inequality present in the provision of dental services to individuals with different racial characteristics. Author contributions Mr. Rauber and Mrs. Knorst did the writing of the article and performed data collection and data analysis; Mrs. Noronha and Mrs. Zemolin performed data collection and revised the manuscript; Mr. Ardenghi collaborated with study conception and funding, and critically revised the text. Funding The Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq – process 161233/2021-0), Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS – process 17/2551-0001083-3) and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001. Data availability The data that support the findings of this study are available from the corresponding author upon reasonable request. Declarations Ethics approval All procedures performed in this study involving human participants were in accordance with the ethical standards of the Research Ethics Committee of the Federal University of Santa Maria (process 3.425.591). Competing interests The authors declare no competing interests. Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. WHO (2003) The World Oral Health Report 2003: continuous improvement of oral health in the 21st century - the approach of the WHO Global Oral Health Programme. Geneva; World Health Organization 2. BRASIL, Ministério da Saúde, Secretaria de Atenção à Saúde, Departamento de Atenção Básica (2011) Projeto SB Brasil 2010: condições de saúde bucal da população brasileira 2010: resultados principais. Ministério da Saúde, Secretaria de Atenção à Saúde, Departamento de Atenção Básica. – Brasília: Ministério da Saúde, 2011 3. Marcenes W Kassebaum NJ Bernabe E Flaxman A Naghavi M Lopez A Global burden of oral conditions in 1990-2010: a systematic analysis Journal of Dental Research 2013 92 7 592 7 23720570 4. Gimenez T Bispo BA Souza DP Viganó ME Wanderley MT Does the decline in caries prevalence of Latin American and Caribbean children continue in the new century? Evidence from Systematic Review with Metanalysis Plos One 2016 21 11 10 5. Listl S Galloway J Mossey PPA Marcenes W Global economic impact of dental diseases J Dent Res 2015 94 10 1355 1136 26318590 6. Petersen PE (2003) The World Oral Health Report 2003: continuous improvement of oral health in the 21st century--the approach of the WHO Global Oral Health Programme. Community Dent Oral Epidemiol 2(1):3–23 7. Freire MCM Reis SCGB Figueiredo N Peres KGP Moreira RS Antunes JLF Individual and contextual determinants of dental caries in Brazilian 12-year-olds in 2010 Rev Saúde Pública 2013 47 3 40 49 24626580 8. Schwendicke F Dorfer CE Schlattmann P Foster-Page L Thomson WM Paris S Socioeconomic inequality and caries: a systematic review and meta-analysis J Dent Res 2015 4 10 18 9. Peres MA Macpherson LMD Weyant RJ Daly B Venturelli R Mathur MR Listl S Celeste RK Guarnizo-Herreño CC Kearns C Benzian H Allison P Rg W Oral diseases: a global public health challenge Lancet 2019 394 249 260 31327369 10. Jin LJ Lamster IB Greenspan JS Pitts NB Scully C Warnakulasuriya S Global burden of oral diseases: emerging concepts, management and interplay with systemic health Oral Dis 2016 22 7 609 619 26704694 11. Guedes RS Piovesan C Antunes JL Mendes FM Ardenghi TM Assessing individual and neighborhood social factors in child oral health-related quality of life: a multilevel analysis Qual Life Res 2014 23 9 2521 2530 24740326 12. Sfreddo CS Moreira CHC Celeste RK Nicolau B Ardenghi TM Pathways of socioeconomic inequalities in gingival bleeding among adolescents Community Dent Oral Epidemiol 2019 47 2 177 184 10.1111/cdoe.12441 30569569 13. Menegazzo GR Knorst JK Emmanuelli B Mendes FM Ardenghi DM Ardenghi TM Effect of routine dental attendance on child oral health-related quality of life: a cohort study Int J Paediatr Dent 2020 30 4 459 467 32031276 14. Lopes RT Neves ÉTB Gomes MC Paiva SM Ferreira FM Granville-Garcia AF Family structure, sociodemographic factors and type of dental service associated with oral health literacy in the early adolescence Cien Saude Colet 2021 26 3 5241 5250 34787215 15. Silveira ER, Cademartori MG, Schuch HS, Corrêa MB, Ardenghi TM, Armfield J, Horta BL, Demarco FF (2021) The vicious cycle of dental fear at age 31 in a birth cohort in Southern Brazil. Community Dent Oral Epidemiol 49(4):354–361 16. Oliveira RF Haikal DS Carreiro DL Silveira MF Lima Martins AMEB Equidade no uso de serviços odontológicos entre adolescentes brasileiros: uma análise multinível Revista Brasileira de Geografia Médica e da Saúde 2018 14 27 14 29 17. Moraes RB, Menegazzo GR, Knorst JK, Ardenghi TM (2020) Availability of public dental care service and dental caries increment in children: a cohort study. J Public Health Dent:1–8 18. Boing AF Bastos JL Peres KG Antunes JL Peres MA Social determinants of health and dental caries in Brazil: a systematic review of the literature between 1999 and 2010 Rev Bras Epidemiol 2014 17 102 115 25409641 19. Souza JG Costa Oliveira BE Martins AM Contextual and individual determinants of oral health-related quality of life in older Brazilians Qual Life Res 2017 26 5 1295 1302 27822609 20. Chisini LA Noronha TG Ramos EC Dos Santos-Junior RB Sampaio KH Faria-E-Silva AL Corrêa MB Does the skin colour of patients influence the treatment decision-making of dentists? A randomized questionnaire-based study Clin Oral Investig 2019 23 3 1023 1030 29934799 21. Solar O, Irwin A (2010) A conceptual framework for action on the social determinants of health. Social Determinants of Health Discussion Paper 2 (Policy and Practice). Geneva; World Health Organization 22. IBGE (2019) Desigualdades Sociais por Cor ou Raça no Brasil. Rio de Janeiro; IBGE 23. Vilella KD Alves SGA De Souza JF Fraiz FC Assunção LRS The association of oral health literacy and oral health knowledge with social determinants in pregnant Brazilian women J Community Health 2016 41 5 1027 1032 27013224 24. Mathias FB Cademartori MG Goettems ML Factors associated with children’s perception of pain following dental treatment Eur Arch Paediatr Dent 2020 21 1 137 143 31236833 25. Johal A Ashari AB Alamiri N Fleming PS Qureshi U Cox S Pandis N Pain experience in adults undergoing treatment: a longitudinal evaluation Angle Orthod 2018 88 3 292 298 29509026 26. Wan S Tao L Liu M Liu J Prevalence of toothache in Chinese adults aged 65 years and above Community Dent Oral Epidemiol 2021 49 6 522 532 33829523 27. Locker D Grushka M The impact of dental and facial pain J Dent Res 1987 66 9 1414 1417 3476612 28. Breivik H Bond MJ Why pain control matters in a world full of killer diseases Pain Clinical Updates 2004 12 4 1 4 29. Ortiz FR Tomazoni F Oliveira MDM Piovesan C Mendes FM Ardenghi TM Toothache, associated factors, and its impact on oral health-related quality of life (OHRQoL) in Preschool Children Braz Dent J 2014 25 6 546 553 25590204 30. Rauber ED, Menegazzo GR, Knorst JK, Bolsson GB, Ardenghi TM. (2021) Pathways between toothache and children's oral health-related quality of life. Int J Paediatr Dent 31(5):558–564 31. Krisdapong S Prasertsom P Rattanarangsima K Sheiham A School absence due to toothache associated with sociodemographic factors, dental caries status, and oral health-related quality of life in 12- and 15-year-old Thai children J Public Health Dent 2013 73 4 321 328 24032357 32. Freire MCM Corrêa-Faria P Costa LR Effect of dental pain and caries on the quality of life of Brazilian preschool children Rev Saude Publica 2018 52 30 29641655 33. Darley RM Karam SA Costa FDS Correa MB Demarco FF Association between dental pain, use of dental services and school absenteeism: 2015 National School Health Survey, Brazil Epidemiol Serv Saude 2021 30 1 e2020108 33729375 34. Boeira GF Correa MB Peres KG Peres MA Santos IS Matijasevich A Barros AJ Demarco FF Caries is the main cause for dental pain in childhood: findings from a birth cohort Caries Res 2012 46 5 488 495 22813889 35. Knorst JK Menegazzo GR Emmanuelli B Effect of neighborhood and individual social capital in early childhood on oral health-related quality of life: a 7-year cohort study Qual Life Res 2019 28 1773 1782 30963360 36. Tondolo Junior J Knorst JK Menegazzo GR Emmanuelli B Ardenghi TM Influence of malocclusion on oral health-related quality of life in children: a seven-year cohort study Dent Press J Orthod 2021 26 2 1 23 37. Knorst JK Vettore MV Brondani B Emmanuelli B Tomazoni F Ardenghi TM Sense of coherence moderates the relationship between social capital and oral health-related quality of life in schoolchildren: a 10-year cohort study Health Qual Life Outcomes 2022 20 1 56 35366896 38. Silva-Júnior IF Hartwig AD Goettems ML Azevedo MS Comparative study of dental pain between children with and without a history of maltreatment J Oral Facial Pain Headache 2019 33 3 287 293 30893406 39. IBGE (2010) Síntese de Indicadores Sociais. Uma análise das condições de vida da população brasileira. Rio de Janeiro; IBGE 40. Ismail AISW Sohn W Tellez M Amaya A Hasson HB The International Caries Detection and Assessment System (ICDAS): an integrated system for measuring dental caries Community Dent Oral Epidemiol 2007 35 170 178 17518963 41. World Health Organization- WHO (2013) Oral Health Surveys: Basic Methods 5th edition. Geneva; World Health Organization 42. Igartua JJ Hayes AF Mediation, moderation, and conditional process analysis: concepts, computations, and some common confusions Span J Psychol 2021 24 e49 35923144 43. Machado FW Perroni AP Nascimento GG Goettems ML Boscato N Does the sense of coherence modifies the relationship of oral clinical conditions and oral health-related quality of life? Qual Life Res 2017 26 8 2181 2187 28321602 44. Peres MA Peres KG Frias AC Antunes JL Contextual and individual assessment of dental pain period prevalence in adolescents: a multilevel approach BMC Oral Health. 2010 10 20 20707920 45. Gupta N Vujicic M Yarbrough C Harrison B Disparities in untreated caries among children and adults in the U.S., 2011-2014 BMC Oral Health 2018 18 1 1 9 29301577 46. Costa F, Wendt A, Costa C, Chisini LA, Agostini B, Neves R, Flores T, Correa MB, Demarco F (2021) Racial and regional inequalities of dental pain in adolescents: Brazilian National Survey of School Health (PeNSE), 2009 to 2015. Cad Saude Publica 37(6) 47. Plessas A To what extent do patients’ racial characteristics affect our clinical decisions? Evid Based Dent 2019 20 4 101 102 31863040 48. Patel N Patel S Cotti E Bardini G Mannocci F Unconscious racial bias may affect dentists’ clinical decisions on tooth restorability: a randomized clinical trial JDR Clin Trans Res 2019 4 1 19 28 30931761 49. Massoni ACLT Porto É Ferreira LRBO Silva HP Gomes MDNC Perazzo MF D'avila S Granville-Garcia AF Access to oral healthcare services of adolescents of a large-size municipality in northeastern Brazil Braz Oral Res 2020 34 29 50. Ofili DC Esu EB Ejemot-Nwadiaro RI Oral hygiene practices and utilization of oral healthcare services among in-school adolescents in Calabar, Cross River State, Nigeria Pan Afr Med J 2020 36 300 33117494 51. Robison V, Wei L, Hsia J (2020) Racial/Ethnic Disparities Among US Children and Adolescents in Use of Dental Care. Prev Chronic Dis 30;17:E71 52. Araújo Júnior CAS Rebelo Vieira JM Rebelo MAB Herkrath FJ Herkrath APCQ de Queiroz AC Pereira JV Vettore MV The influence of change on sense of coherence on dental services use among adolescents: a two-year prospective follow-up study BMC Oral Health 2021 21 1 663 34953499 53. Hadler-Olsen E Jönsson B Oral health and use of dental services in different stages of adulthood in Norway: a cross sectional study BMC Oral Health 2021 21 1 257 33985488 54. Pentapati KC Yeturu SK Siddiq H Global and regional estimates of dental pain among children and adolescents-systematic review and meta-analysis Eur Arch Paediatr Dent 2021 22 1 1 12 32557184 55. Macedo TFF Abreu MHNG Castro Martins R Matta-Machado ATG da Silveira PR de Castilho LS Vargas-Ferreira F Contextual and individual factors associated with dental pain in adolescents from Southeastern Brazil Braz Oral Res 2021 35 6 9 56. Grusky David Varner Charles MATTINGLY MARYBETH Pathways magazine 2017 Stanford, CA Stanford Center on Poverty and Inequality 57. Costa NC, Abreu MHNG, Pinto RS, Vargas-Ferreira F, Martins RC (2022) Factors associated with toothache in 12-year-old adolescents in a southeastern state of Brazil. Braz Oral Res 36:e57 58. Brondani B Knorst JK Tomazoni F Cósta MD Vargas AW Noronha TG Mendes FM Ardenghi TM Effect of the COVID-19 pandemic on behavioural and psychosocial factors related to oral health in adolescents: a cohort study Int J Paediatr Dent 2021 31 4 539 546 33730371 59. Muniz JO Sobre o uso da variável raça-cor em estudos quantitativos Revista de Sociologia e Política 2010 18 36 277 291
PMC009xxxxxx/PMC9989581.txt	==== Front Stat Biosci Stat Biosci Statistics in Biosciences 1867-1764 1867-1772 Springer US New York 9364 10.1007/s12561-023-09364-y Article Simultaneous Confidence Band Approach for Comparison of COVID-19 Case Counts http://orcid.org/0000-0002-9277-4243 Shao Q. [email protected] grid.267337.4 0000 0001 2184 944X Department of Mathematics and Statistics, The University of Toledo, Toledo, OH 43606 USA 7 3 2023 2023 15 2 372383 26 8 2022 4 1 2023 8 2 2023 © The Author(s) under exclusive licence to International Chinese Statistical Association 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. The outbreak of the novel coronavirus (COVID-19) was declared to be a global emergency in January of 2020, and everyday life throughout the world was disrupted. Among many questions about COVID-19 that remain unanswered, it is of interest for society to identify whether there is any significant difference in daily case counts between males and females. The daily case count sequences are correlated due to the nature of a contagious disease, and contain a nonlinear trend owing to several unexpected events, such as vaccinations and the appearance of the delta variant. It is possible that these unexpected events have changed the dynamical system that generates data. The classic t-test is not appropriate to analyze such correlated data with a nonconstant trend. This study applies a simultaneous confidence band approach in an attempt to overcome these difficulties; that is, a simultaneous confidence band for the trend of an autoregressive moving-average time series is constructed using B-spline estimation. The proposed method is applied to the daily case count data of seniors of both genders (at least 60 years old) in the State of Ohio from April 1, 2020 to March 31, 2022, and the result shows that there is a significant difference at the 95% confidence level between the two gender case counts adjusted for the population sizes. Keywords COVID-19 Case counts B-splines Simultaneous confidence band Autoregressive moving-average time series issue-copyright-statement© International Chinese Statistical Association 2023 ==== Body pmcIntroduction The outbreak of the coronavirus disease (COVID-19) in late 2019 has profoundly changed all walks of life and has raised many challenging research questions over the development of the pandemic. It is the first such pandemic outbreak since the 1918 influenza, commonly known by the misnomer “Spanish flu”. It is the first time in human history that a huge amount of data related to a pandemic has been recorded, which makes it possible to analyze the biological, medical and social aspects of COVID-19, and which provides statisticians and data scientists with tremendous yet challenging opportunities for COVID-19 studies [1]. There have been some attempts to obtain valuable information for society to help identify risk factors and gain an understanding of the coronavirus, in spite of there being so far a limited amount of publicly available data. The primary goal of the paper is to propose an appropriate statistical learning method, using publicly available COVID-19 data, to obtain information about how the coronavirus affects male and female seniors differently. Many aspects of this virus have been studied based on publicly accessible data which are updated daily from all over the world [2–5]. In particular, the effects of gender and age on COVID-19 have received a great deal of attention. Senior people tend to have many comorbidities which are associated with most of the senior deaths [6–9], and the coronavirus tends to exacerbate preexisting health problems. In addition, gender seems to play a role too, and male tends to be more vulnerable. The paper [10] presented the age and gender effects on the fatality rate using the COVID-19 data of the State of Ohio. The authors applied logistic regression to identify factors on the death probability of a COVID-19 patient and concluded that age and gender were significant factors. One of the critical assumptions for logistic regression is that the log odds ratio can be modeled by a linear function [11]. However, many unexpected events, such as vaccination that began in early 2021 and the delta variant that appeared in June–July 2021, could have changed the data generating mechanism. In other words, the linear assumption of logistic regression is too restrictive. This study focuses on the senior case count comparison between April 1, 2020 and March 31, 2022, inclusive, and aims at investigating whether the impact of male and female on the case count is significant by modeling the difference of log transformed case counts of the two genders {yt}t=1n after population size adjustment. The paper [12] proposed a correction in the analysis of variance test for autoregressive moving-average time series (ARMA). However, the time series {yt}t=1n are not only correlated due to the nature of a contagious disease, but also contain a nonlinear trend due to several unexpected events, such as vaccinations and the appearance of the delta variant. The dots in Fig. 1 are the observations of {yt}t=1n, which do not unveil any pattern of the trend or of the mean function that can be easily described by an analytical function. This observation about the data plotted in Fig. 1 suggests that a nonparametric approach, such as splines, is more appropriate. B-spline estimation has been widely applied to describe an unknown mean function [13–16]. In particular, [17] proposed a simultaneous confidence band (SCB) approach for the mean function based on B-spline estimation, and [18] extended it to autoregressive time series with unknown nonlinear trend function.Fig. 1 Scatter plot for {yt}t=1730 and 95% SCB The paper extends the confidence band approach of AR to a more general ARMA setting, and applies it to the COVID-19 senior daily case count comparison of males and females in the State of Ohio. The paper is organized as follows. In Sect. 2, the details of the data set to be analyzed are provided; in Sect. 3, the B-splines trend function estimation is reviewed; in Sect. 4, the construction of confidence bands is described, and some simulation studies are presented; in Sect. 5, the confidence band approach is applied to the senior COVID-19 data; in Sect. 6, the paper concludes with some discussion. Data The State of Ohio established a website1 which provides the public with information and data about COVID-19 in the state. The daily case count data of male and female seniors (at least 60 years old) from April 1, 2020 to March 31, 2022, inclusive, were downloaded from the website. There are n=730 daily case counts for each group, and there is no missing data or zero count during this period. According to the summary of the statistics in Table 1, the female case count has larger values in all major statistics, such as mean and median. This case discrepancy might be resulted in by the different of the populations of these two groups—the male senior population is smaller than the female counterpart in Ohio. Define a time series {yt}t=1n as the differenced log transformed daily case counts of the two groups: male senior COVID-19 patients and female senior COVID-19 patients. The scatter plot in Fig. 1 shows that {yt}t=1n exhibits some nonlinear pattern, and tends to be negative, or the male senior group seems to have a lower case count than the female counterpart.Table 1 Summary of statistics for case counts Minimum Q1 Median Mean Q3 Maximum Variance SD Male 9.00 75.25 140.50 326.27 450.50 2434.00 152,480.9 390.488 Female 14.00 88.25 160.00 388.00 543.50 3067.00 227,456.5 476.924 {yt}t=1730 -1.06 -0.23 -0.16 -0.16 -0.09 0.86 0.02 0.15 Q1 is the first quartile; Q3 is the third quartile; SD is the standard deviation The population difference is taken into account and calculated according to the information in the State of Ohio in 2019–2020.2 The horizontal dashed line in Fig. 1 is y=-0.227, which is the differenced log male and female senior populations. Most of the observations {yt}t=1n are above the line y=-0.227, which suggests that the male senior group has a higher case rate or are more vulnerable to COVID-19. However, in Fig. 1, the case count of the male senior group outnumbered the case count of the female senior group at the first peak which occurred in the beginning of the pandemic on April 16, 2020, but the opposite situation happened at the second large peak more than a year later on June 19, 2021. Therefore, it is not obvious which gender group is more vulnerable, and the confidence band approach proposed in this paper will provide rigorous statistical evidence to this end. B-spline Trend Estimation The proposed confidence band is constructed based on a B-spline estimator for the mean function or trend g. B-spline estimation for functions is one of the nonparametric methods that are widely applied. We start with the B-spline estimation and provide the details about how to construct a (1-α)% simultaneous confidence band. A realization {yt}t=1n of a time series is assumed to follow the model below:1 yt=g(ut)+xt, where g(ut) is a smooth trend function with ut=t/n and {xt} is an autoregressive and moving-average time series with orders p and q (ARMA(p, q)) with mean E(xt)=0 and covariance γk=Cov(xt,xt-k)2 xt-∑k=1pϕkxt-k=ϵt+∑k=1qθkϵt-k. In the ARMA model (2) above, {ϵt} is a white noise sequence; that is, mean E(ϵt)=0 and variance Cov(ϵt,ϵt-k)=σ2 if k=0 and 0 otherwise. Hereafter, bold letters are used for vectors. The default of a vector is column, and a superscript T is used sometimes for the transpose operation of a matrix. For example, y=(y1,…,yn)T is a vector that is corresponding to all the observations. This paper considers the case that the unknown trend function g is estimated by degree one B-splines or piecewise linear B-splines for two reasons: a higher degree B-spline estimator does not provide much more gain; a rigorous proof for a confidence band based on the piecewise linear B-splines can be obtained. Let N be an integer, and let [-h,1] be divided into (N+2) equally spaced subintervals Jj=jh,(j+1)h,j=-1,0,…,N-1 and JN=Nh,1, of width h=(N+1)-1. The integer N is a tuning parameter. The basis of a piecewise linear spline space is b(u)=(b-1(u),…,bN(u))T with bj(u) being defined as follows:3 bj(u)=u/h-j(u),j=j(u),j(u)+1-u/h,j=j(u)-1,0,Otherwise,, where j(u) is the location index of u for u∈Jj(u). Any b-1(u) is not zero in at most two adjacent subintervals. Figure 2 is an example of the degree one B-splines {bj,1(u)}j=-13, where h=0.25 and N=3. The standardized basis c(u)=(c-1(u),…,cN(u))T is defined as4 cj(u)=bj(u)∫01bj2(u)du1/2=u/h-jwjh/3,j=j(u),j+2-u/hwjh/3,j=j(u)-1,0,Otherwise with5 wj=2,0≤j≤N-1,1,j=-1,N. Next, define vectors {cj}j=-1N for a realization of time series y by cj = (cj(u1), …, cj(un))T, and a n×(N+2) matrix C=(c-1,…,cN). The B-spline estimator g^ is a linear combination of cjg^=Cβ^,, where the coefficients β^=(β^-1,…,β^N)T minimizes(y-Cβ)T(y-Cβ). Thus from the classic theory of the least squares we can obtain for u∈[0,1],6 g^(u)=cT(u)1nCTC-11nCTy. More detailed descriptions about B-splines and their applications in Statistics can be found, for example, in [19] and [20].Fig. 2 Degree one B-splines {bj(u)}j=-13 Construction of Confidence Band A simultaneous confidence band is constructed from the residuals of the trend estimate in (6). There are two major steps: in the first step, g^ is calculated by (6), and residuals {x^t}t=1n are calculated from x^t=yt-g^(ut); in the second step, the parameters and estimates needed for the confidence band are obtained based on the matrix C and {x^t}t=1n, and thus a (1-α)% SCB is constructed. For an integer m≥0 and ν∈0,1, denote by Cm,ν0,1 the space of functions whose m-th derivatives satisfy Hölder conditions of order ν, i.e.,7 Cm,ν0,1=ϕ:0,1→Rϕm,ν=sup0≤x<y≤1ϕmx-ϕmyx-yν<+∞. The following assumptions are necessary for the proposed (1-α)% SCB for a smooth trend function g(u). The trend function g(·)∈Cm,ν0,1, m<2. The number of interior knots N satisfies n1/4m+ν≪N≪n1/2. The parameter space Ξ is compact and consists of α such that all roots of Φ(α,z)=0 and Θ(α,z)=0 are larger than one in absolute value, and they have no common roots. The true parameter value α0 is in the interior of the parameter space Ξ. The innovations ϵtt=-∞∞ are i.i.d. with E(ϵ14)<∞. These assumptions ensure that some uniform consist properties of g^ as an estimate of g and of the residuals x^t as a substitute for unobservable ARMA time series xt. According to [21], under assumptions 1–2, it is straightforward to obtain8 max1≤t≤nEg(ut)-g^(ut)2=on-1/2; according to [22], under assumption 3, a ARMA model is causal and invertible; under assumptions 1–4, the asymptotic properties of the maximum likelihood estimators for ARMA coefficients are not altered using the residuals {x^t}t=1nx^t=yt-g^(ut) as a substitute. One of the parameters needed in the confidence band is the zero spectrum τ2 of the ARMA series {xt}t=1n:τ2=γ0+2∑k≥1γk,, where γk is the autocorrelation at lag k, γk=Cov(xt,xt+k). One can obtain the estimate γ^k of autoregressive covariance at any lag k by the sample autocovariance based on {x^t}t=1n as followsγ^k=1n∑t=k+1nx^tx^t-k. However, it requires a large sample size. For the COVID-19 data to be analyzed, n=730, and the method introduce below works better. Another method to obtain γ^k is based on the residual sequence {x^t}t=1n. In particular, {x^t}t=1n is treated as the replacement of unobservable time series {xt}t=1n, and the maximum likelihood estimates ϕ^=(ϕ^1,…,ϕ^p)T is calculated for the autoregressive coefficients and θ^=(θ^1,…,θ^q)T for the moving-average coefficients. Since these estimators ϕ^,θ^ are consistent according to [21], one can obtain the estimate γ^k from the ARMA model:9 x^t-∑k=1pϕ^kx^t-k=ϵ^t+∑k=1qθ^kϵ^t-k,, where {ϵ^t}t=1n is the residuals of the ARMA(p, q) time series model. The theoretical autocorrelation of model (9) with known coefficients ϕ^,θ^ can be calculated using the algorithms in [22]. In addition, this procedure to obtain τ^2 can be easily carried out by the functions arima for estimates ϕ^,θ^ and ARMAacf for γ^k of the R which is a language and environment for statistical computing [23]. The procedure exhibits a satisfactory performance in the simulation studies later in this section, and will be applied to the data analysis in the next section. There are some other approaches to estimate γk and thus τ2, for example [24]. Let the matrix S be the inverse of the (N+2)×(N+2) band matrix V defined below:10 (V)j,j′=-1N=1,j=j′;1/4,\|j-j′\|=1and0≤j,j′≤N-1;2/4,\|j-j′\|=1andjorj′=-1,N;0,Otherwise. In particular, the 2×2 submatrix Sj of S isSj=sj-1,j-1sj-1,jsj,j-1sj,j. Definedα=1-2log(N+1)-1log(α/2)+12loglog(N+1)+log(4π), andη^n2(u)=3nh∑\|k\|=0⌈nh⌉γ^kδT(u)Sj(u)δ(u), withδ(u)=j(u)+1-u/hwj(u)-1,u/h-j(u)wj(u), where wj(u) is defined in (5). It can be shown that under Assumptions 1–4,11 lim infn→∞Pg(u)∈g^(u)±2{log(N+1)}1/2η^n(u)dα/2≥1-α, which implies that the 100(1-α)% SCB is constructed as follows: for any 0≤u≤112 g^(u)±2{log(N+1)}1/2η^n(u)dα/2. The proof of (11) is a generalization of the proof of Theorem 2.1 of [18] for the autoregressive time series based on Theorem 4 of [21], and the details are omitted. Simulation studies are performed for {yt}t=1n generated from model (1) with constant function g=1 and ten ARMA models: nine ARMA(1,1) and one ARMA(2,2). These models with coefficients in Table 2 are chosen so that they are representatives of ARMA(1,1) with different shapes of autocorrelation functions (ACF). Figure 3 illustrates ACF’s of some of the models. The coefficients of ARMA(2,2) are obtained from the COVID-19 data to be analyzed in the next section—some of the autocorrelation functions are either non-negative or non-positive at any lags, and the others are alternate.Table 2 Simultaneous confidence band relative frequencies for ARMA(1,1) (ϕ1,θ1) N=n0.2 N=n0.3 n=400 n=800 n=2000 n=400 n=800 n=2000 (-0.8,-0.8) 0.996 0.996 0.998 0.924 0.950 0.976 (-0.6,-0.6) 1.000 1.000 0.998 0.974 0.994 0.998 (-0.8,0.2) 1.000 1.000 1.000 0.998 1.000 0.998 (0.8, 0.8) 1.000 1.000 1.000 0.988 1.000 0.994 (0.6, 0.6) 1.000 1.000 0.998 0.990 0.996 0.998 (0.2, 0.8) 1.000 1.000 1.000 1.000 0.998 0.996 (0.4,-0.8) 0.982 1.000 1.000 0.860 0.980 0.988 (0.2,-0.3) 0.980 0.998 1.000 0.834 0.942 0.992 (0.2,-0.4) 0.996 1.000 1.000 0.918 0.992 0.996 Five hundred sample paths are simulated for each of the three sample sizes n=400, 800, 2000. Two numbers of knots, N=n0.2 and N=n0.3, are chosen for the B-Spline fit. The 95% confidence bands are constructed from (12). From the relative frequencies of the bands that contains g in Tables 2 and 3, the smaller number of knots tends to outperform the larger one. The bands based on N=n0.2 of knots are conservative, in that all the empirical rates are greater than the nominal rate 95%. On the other hand, some of empirical rates based on N=n0.3 appear to be smaller than 95% at n=400, in particular, for the models, such as ϕ1=0.4 and θ1=-0.8, the ACF of which is always negative as shown in Fig. 3.Fig. 3 Autocorrelation functions of some ARMA(1,1) models Table 3 Simultaneous confidence band relative frequencies for ARMA(2,2) (ϕ1,ϕ2,θ1,θ2) N=n0.2 N=n0.3 n=400 n=800 n=2000 n=400 n=800 n=2000 (0.78,-0.70,-0.76,0.81) 0.998 1.000 1.000 0.986 0.998 0.998 COVID-19 Data Analysis To estimate the trend g, the piecewise linear B-splines is applied to the differenced log case counts {yt}t=1730, and N=n0.2 is used. The estimates {g^(ut)}t=1730 are calculated, which is illustrated by the solid curve in Fig. 1, and the residuals {x^t}t=1730 of the B-splines are obtained. The ARMA model selection follows an iterative procedure recommended by [25] using the criterion Akaike Information Criterion (AIC). In particular, the AIC is calculated for a model with tentative values for the autoregressive order p and the moving-average order q, and then compared with the AIC of the previous chosen model. According to AIC, the ARMA(2, 2) is selected for the residuals {x^t}t=1730 with the estimates and their standard errors being ϕ^1=0.78±0.12, ϕ^2=-0.70±0.10, θ^1=-0.76±0.10, θ^2=0.81±0.07. The sample autocorrelations of the ARMA(2, 2) residuals {ϵ^t}t=1730 at lags 1–20 are reasonably small and within the 95% confidence intervals in Fig. 4, which indicates that ARMA(2, 2) is a good fit.Fig. 4 ARMA (2, 2) residual sample autocorrelation function In Fig. 1, the dashed curves are the lower and upper bounds of the 95% SCB. The differenced log populations of the male seniors and female seniors, y=-0.227, is taken into account. The age adjustment line y=-0.227 is not completely contained in the 95% SCB, such as those from November 2020 to March 2021. The percentage of the number of time points at which y=-0.227 is below the lower bound is as high as 49.3%, almost half of the times in the study period. The male case count tends to be proportionally greater than the female counterpart. Discussion A 95% SCB is proposed to test whether the case counts of senior groups of both genders are significantly different after the surveillance COVID-19 data of the State of Ohio are adjusted according to their population sizes. It is a powerful statistical inference tool that gives a simultaneous band for the trend function of an ARMA time series. The 95% SCB which is constructed based on the B-splines does not contain the constant baseline y=-0.227—sometimes the baseline is above or below the lower bound, which implies that gender is a factor that has a significant impact on the case counts of senior groups of both genders. Although this result coincides with some observation at the beginning of pandemic outbreak, for example [26] and [27], the SCB approach takes nonconstant trend function and correlation into account when considering the data over two years. The biological or medical aspects for such gender imbalance should be further investigated [28, 29]. The data analysis results are valuable to help reduce or even prevent illness from a similar pandemic in the future. However, this research has some limitations. First, the population size adjustment is calculated based on the records in 2019–2020, not in the period of the study. When the more precise population sizes are available, the study should be updated. Secondly, the development of technology makes surveillance data so easily available, but a great deal of work needs to be done to improve the accuracy [30, 31]). The scientific value of a study relies on the quality of its data. Thirdly, the publicly available COVID-19 data overall are very limited. More comprehensive analysis could reveal more useful information to the general public and policy makers when more data on the patients, such as comorbidities, were available. Acknowledgements The author would like to thank referees for careful reading and constructive suggestions. Declarations Conflict of interest The author does not have any financial interests that are directly or indirectly related to the work submitted for publication. 1 https://coronavirus.ohio.gov/wps/portal/gov/covid-19/dashboards/overview. 2 https://suburbanstats.org/population/how-many-people-live-in-ohio. ==== Refs References 1. Kim M Gu Z Yu S Methods, challenges, and practical issues of COVID-19 projection: a data science perspective J Data Sci 2021 19 219 242 10.6339/21-JDS1013 2. Charvadeh YK Yi GY Bian Y Is 14-days a sensible quarantine length for COVID-19? Examinations of some associated issues with a case study of COVID-19 incubation times Stat Biosci 2022 14 175 190 10.1007/s12561-021-09320-8 34522235 3. Gaythorpe KAM Bhatia S Mangal T Childrens role in the COVID-19 pandemic: a systematic review of early surveillance data on susceptibility, severity, and transmissibility Sci Rep 2021 11 13903 10.1038/s41598-021-92500-9 34230530 4. Nogueira PJ de Araújo Nobre M Costa A The role of health preconditions on COVID-19 deaths in Portugal: evidence from surveillance data of the first 20293 infection cases J Clin Med 2020 9 8 2368 10.3390/jcm9082368 32722159 5. Ullrich A Schranz M Rexroth U Impact of the COVID-19 pandemic and associated non-pharmaceutical interventions on other notifiable infectious diseases in Germany: an analysis of national surveillance data during week 1–2016-week 32–2020 Lancet Reg Health Europe 2021 6 100103 10.1016/j.lanepe.2021.100103 34557831 6. Dai M Liu D Liu M Patients with cancer appear more vulnerable to SARS-CoV-2: a multicenter study during the COVID-19 outbreak Cancer Discov 2020 10 783 791 10.1158/2159-8290.CD-20-0422 32345594 7. Mi J Zhong W Huang C Zhang W Tan L Ding L Gender, age and comorbidities as the main prognostic factors in patients with COVID-19 pneumonia Am J Transl Res 2020 12 6537 6548 33194050 8. Mukherjee S Pahan K Is COVID-19 gender-sensitive? J Neuroimmune Pharmacol 2021 16 38 47 10.1007/s11481-020-09974-z 33405098 9. Qian J Zhao L Ye R Age-dependent gender differences in COVID-19 in Mainland China: comparative study Clin Infect Dis 2020 71 2488 2494 32473009 10. Nguyen H Shao Q Risk identification and prediction for COVID-19 mortality Transl Univ Toledo J Med Sci 2021 9 39 49 11. Agresti A Categorical data analysis 2002 2 New Jersey Wiley Interscience 12. Liu G Shao Q Woody J Lund R Testing seasonal means in time series data Environmetrics 2016 27 198 211 10.1002/env.2383 13. Huang JZ Local asymptotics for polynomial spline regression Ann Stat 2003 31 1600 1635 10.1214/aos/1065705120 14. Stone CJ Hansen M Kooperberg C Truong Y Polynomial splines and their tensor products in extended linear modeling (with discussion) Ann Stat 1997 25 1371 1470 15. Wang L Yang L Spline estimation of single-index models Stat Sin 2009 19 765 783 16. Xue L Yang L Additive coefficient modelling via polynomial spline Stat Sin 2006 16 1423 1446 17. Wang J Yang L Polynomial spline confidence bands for regression curves Stat Sin 2009 19 325 342 18. Shao Q Yang L Polynomial spline confidence bands for time series trend J Stat Plan Inference 2012 142 1678 1689 10.1016/j.jspi.2012.02.028 19. de Boor C A practical guide to splines 2001 New York Springer-Verlag 20. DeVore RA Lorentz GG Constructive approximation: polynomials and splines approximation 1993 Berlin Springer-Verlag 21. Shao Q Yang L Oracally efficient estimation and consistent model selection for auto-regressive moving average time series with trend J R Stat Soc (Ser B) 2017 79 507 524 10.1111/rssb.12170 22. Brockwell PJ Davis RA The analysis of time series: theory and methods 1991 2 New York Springer 23. R Core Team (2022) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna. http://www.R-project.org/ 24. Hall P Keilegom IV Using difference-based methods for inference in nonparametric regression with time series errors J R Stat Soc (Ser B) 2003 65 443 456 10.1111/1467-9868.00395 25. Box GEP Jenkins GM Reinsel GC Time series analysis: forecasting and control 1994 3 New Jersey Prentice-Hall International 26. Shao Q Thompson G Thompson A COVID-19 risk factor identification based on Ohio data Transl Univ Toledo J Med Sci 2020 8 6 14 27. Zheng S Qin J Zhou Y Assessment of effects of age and gender on the incubation period of COVID-19 with a mixture regression model J Data Sci 2021 19 253 268 10.6339/21-JDS992 28. Dangis A De Brucker N Heremans A Gillis M Frans J Demeyere A Symons R Impact of gender on extent of lung injury in COVID-19 Clin Radiol 2020 75 7 554 556 10.1016/j.crad.2020.04.005 32359867 29. Giacomelli A De Falco T Oreni L Impact of gender on patients hospitalized for SARS-COV-2 infection: a prospective observational study J Med Virol 2021 93 4597 4602 10.1002/jmv.26933 33710652 30. Alamo T Reina DG Mammarella M Abella A Covid-19: open-data resources for monitoring, modeling, and forecasting the epidemic Electronics 2020 9 827 10.3390/electronics9050827 31. Tarantola D Dasgupta N COVID-19 surveillance data: a primer for epidemiology and data science Am J Public Health 2021 111 614 619 10.2105/AJPH.2020.306088 33476236
PMC009xxxxxx/PMC9994784.txt	==== Front Food Environ Virol Food Environ Virol Food and Environmental Virology 1867-0334 1867-0342 Springer US New York 36890342 9552 10.1007/s12560-023-09552-5 Original Paper High-Intensity Ultraviolet-C Irradiation Efficiently Inactivates SARS-CoV-2 Under Typical Cold Chain Temperature Li Peiru 12 Ke Xianliang 3 Leng Dongmei 12 Lin Xian 3 Yang Wenling 3 http://orcid.org/0000-0001-7380-3865 Zhang Hainan [email protected] 12 Tian Changqing 12 Xu Hongbo 1 Chen Quanjiao [email protected] 3 1 grid.9227.e 0000000119573309 Key Laboratory of Science and Technology on Space Energy Conversion, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190 China 2 grid.410726.6 0000 0004 1797 8419 University of Chinese Academy of Sciences, Beijing, 100049 China 3 grid.439104.b 0000 0004 1798 1925 CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071 Hubei China 8 3 2023 2023 15 2 123130 20 7 2022 27 2 2023 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. SARS-CoV-2 contaminated items in the cold chain becomes a threat to public health, therefore the effective and safe sterilization method fit for the low temperature is needed. Ultraviolet is an effective sterilization method while its effect on SARS-CoV-2 under low-temperature environment is unclear. In this research, the sterilization effect of high-intensity ultraviolet-C (HIUVC) irradiation against SARS-CoV-2 and Staphylococcus aureus on different carriers at 4 °C and − 20 °C was investigated. The results showed that dose of 15.3 mJ/cm2 achieved more than 3 log reduction of SARS-CoV-2 on gauze at 4 °C and − 20 °C. The vulnerability of coronavirus to HIUVC under − 20 °C was not significantly different than those under 4 °C. Four models including Weibull, biphasic, log-linear tail and log linear were used to fit the survival curves of SARS-CoV-2 and Staphylococcus aureus. The biphasic model fitted best with R2 ranging from 0.9325 to 0.9878. Moreover, the HIUVC sterilization correlation between SARS-CoV-2 and Staphylococcus aureus was established. This paper provides data support for the employment of HIUVC under low-temperature environment. Also, it provides a method of using Staphylococcus aureus as a marker to evaluate the sterilization effect of cold chain sterilization equipment. Graphical Abstract Keywords Cold chain Low temperature Ultraviolet SARS-CoV-2 Sterilization http://dx.doi.org/10.13039/501100001809 National Natural Science Foundation of China 51976232 Tian Changqing the Director's Fund of Technical Institute of Physics and Chemistry, CASissue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction The coronavirus disease 2019 (COVID-19) has spread worldwide since the outbreak in 2019, which causes 562,672,324 infections and 6,367,793 deaths globally according to the most recent data from the World Health Organization (WHO, 2022). Besides, the pandemic caused economic and social disruption, including employment and labor issues, trade restrictions, humanitarian crises and food security. Cold chain plays a great role in maintaining the quality of food, extending the shelf life and cutting down the food waste (Zhao et al., 2018). While during the pandemic, the food cold chain system is at risk of becoming the medium of SARS-CoV-2 transmission and infection (He et al., 2022; Hu et al., 2021; Lu et al., 2021; Qian et al., 2022). The virus-contaminated items in cold processing, refrigeration and freezing, transportation and retailing put a risk to public health (Benkeblia, 2021). In the typical refrigeration and freezing temperature at − 20 °C, the SARS-CoV-2 on the surfaces of food packages might exist for 60 days (Liu et al., 2021). Additionally, relative humidity also affects the viability of the coronavirus (Chan et al., 2011). Over the past year, many imported cold chain products tested positive for COVID-19 at China customs. Besides, there were considerable reports of the outbreaks of COVID-19 in China traced back to the cold chain. For instance, the salmons in a sealed package in cold storage located outside Xinfadi Market in Beijing, China were tested positive for SARS-CoV-2 RNA in June, 2020 (Pang et al., 2020). Infectious SARS-CoV-2 was isolated from the outer surface of an imported frozen cod package in Qingdao, China for the first time during the outbreak in September, 2020. Therefore, Virus sterilization method for cold chain environment is needed to maintain the safety of the cold chain (Guo et al., 2022). In China, the Joint Prevention and Control Mechanism of the State Council of China issued a work plan on the preventive and comprehensive sterilization of imported cold chain food, aiming at effectively inactivating the SARS-CoV-2 during the port inspection, transportation, warehousing and retailing of imported cold chain food (National Health Commission of the People's Republic of China, 2020a). Besides, the State Council of China issued technical guidelines regulating that the inner wall of the container and the outer packaging of the goods should be disinfected (National Health Commission of the People's Republic of China, 2020b). Currently, chemical disinfects are majorly adopted as a sterilization method at customs. However, chemical disinfects are harmful to operators, have the risk of residues and food contamination, and require high intensity labor. Quick, effective and safe sterilization methods fit for the cold environment are urgently needed to establish a safe cold chain system (Chitrakar et al., 2021). High-intensity ultraviolet-C (HIUVC) sterilization is an effective technology for the sterilization of pathogens on surfaces. According to Terms of ultraviolet disinfection technology (GB/T 32092-2015) released by The Standardization Administration of China, low pressure high intensity ultraviolet-C lamp refers to the “mercury vapor lamp that the input electric power is about 0.5–1.5 W per centimeter of arc length, and the output power of germicidal ultraviolet light is about 0.15–0.45 W per centimeter of arc length”. At same dose, it can sterilize the virus at short time, which is beneficial to its application to sterilization scene such as custom, hospital and public transport. Ultraviolet photons damaged the nucleic acid and microorganismal proteins, thus preventing viruses from replicating (Raeiszadeh & Adeli, 2020). Ultraviolet is divided into UVA (320–400 nm), UVB (280–320 nm) and UVC (200–280 nm) according to the spectrum (Darnell et al., 2004). Ultraviolet has been experimentally demonstrated an effective sterilization method against bacteria (Kim & Hung, 2012), SARS-CoV-1 (Duan et al., 2003; Kariwa et al., 2006), HCoV-OC43 (Gerchman et al., 2020). After the outbreak of COVID-19, some studies have been conducted on ultraviolet sterilization of SARS-CoV-2. Generally, the dose required to reach the same effect of inactivation of SARS-CoV-2 increases with the increase of ultraviolet wavelength (Gerchman et al., 2020; Minamikawa et al., 2021; Trivellin et al., 2021b). Therefore, UVC is an efficient sterilization method against SARS-CoV-2. Research on the sterilization effect of UVC on suspension and different carriers has been conducted (Biasin et al., 2021; Bormann et al., 2021; Fischer et al., 2020; Gerchman et al., 2020; Sabino et al., 2020; Storm et al., 2020; Trivellin et al., 2021a). Although significant progress has been made on the sterilization effect of ultraviolet on SARS-CoV-2, the effect under low temperatures is rarely investigated. Also, the comparison of UVC sterilization effect on SARS-CoV-2 and bacteria under low temperatures is absent. In this study, Staphylococcus aureus (S.aureus) was chosen as the bacteria to establish the correlation between SARS-CoV-2 and bacteria because it is easily accessed. Based on the established correlation, S. aureus can be used to evaluate the sterilization effect of sterilization equipment. The study aimed to experimentally evaluate the inactivation effect of HIUVC against SARS-CoV-2 and S. aureus under 4 °C and − 20 °C, which are typical temperatures of the cold chain. The HIUVC sterilization correlation between S. aureus and SARS-CoV-2 was also established. Materials and Methods Instruments The U-shape high-intensity low pressure high intensity ultraviolet-C lamp (GZW250D28W-Z810) with a peak spectrum of 254 nm, is provided by Foshan Comwin Light & Electricity Co., Ltd in Guangdong, China. Two lamps were put in a self-designed apparatus that controlled the exposure time of test samples, as shown in Fig. 1. The apparatus consists of an exposure part and a power supply. The power supply was separated from the lamp to avoid the generation of virus aerosol by the heat dissipation fan in the power supply. As shown in exploded view in Fig. 1, there were two U-type HIUVC lamps of 412 W in the exposure part. The test sample was placed below the light. The ultraviolet irradiance of the light is measured by an ultraviolet irradiance meter (ST 512, SENTRY, Taiwan, China) with the range of 0.01–40.00 mW/cm2 at a response spectrum of 220–275 nm. The sample was placed on the lifting platform. The height of the lift table was adjusted to make the irradiance reach 5.1 mW/cm2, which was evenly distributed in the 2 cm × 2 cm rectangular area with deviation of ± 0.1 mW/cm2. The shutter system was connected to the motor to control the exposure time to keep the lamp output stable. Ultraviolet protective clothes and face masks were worn to avoid the harm of ultraviolet to the skin and eyes of the operators.Fig. 1 HIUVC sterilization instrument Virus and Cell Preparation SARS-CoV-2 isolate (nCoV-2019BetaCoV/Wuhan/WIV04/2019) was obtained from Wuhan Institute of Virology, Chinese Academy of Sciences. The virus sterilization experiment was conducted in the biosafety level-3 (BSL-3) laboratory at National Biosafety Laboratory, Wuhan. The relative humidity in laboratory was in the range of 40–60%. The virus was propagated in Vero E6 cells cultured in Dulbecco’s modified Eagle’s medium (DMEM, Gibco, USA) supplemented with 10% fetal bovine serum (FBS, Gibco, USA). On day 2 post-infection, the culture supernatant was harvested and filtered for virus stocks and tittered through plaque assay. Medical gauze was selected as carrier for microorganism contamination. The size of the carrier is 2.0 × 2.0 cm with one layer, which was sterilized by 121 °C steam and dried before it was inoculated with the microorganism. A drip of 200 μL SARS-CoV-2 was dropped on the gauze in a 35 mm dish (Thermo Fisher Scientific, USA). The inoculum was absorbed into the gauze as it was absorbent. The samples were kept in refrigerator (Haier, China) of 4 °C and − 20 °C for 30 min before HIUVC exposure, separately. Then, the 4 °C and − 20 °C samples were put on precooled ice storage plate. Immediately, the samples were exposed to HIUVC at the irradiance of 5.1 mW/cm2 for 1 s, 3 s and 5 s, respectively. The control group was put in dark place. The control group went through same time with the HIUVC treated group under same temperature. Subsequently, virus samples were transferred aseptically to a centrifuge tube of 50 mL (Corning Life Science, USA). Remaining virus in the dish was eluted with 2 mL DMEM, and transferred to the centrifuge tube mentioned above. The tube was whirled in a vortex mixer with the maximum speed of 5 s/time five times. The virus titer was determined by plaque assay. The experiments were conducted in triplicates. The virus titer was determined by plaque assay as described previously (Lin et al, 2022). Briefly, virus samples were tenfold serial diluted with DMEM. Then, 200 μL of each dilution was incubated with Vero E6 cells. For HIUVC treated samples in which virus titer may be very low, 600 μL of non-diluted samples were directly used for cell infection. After one hour, cells were washed and incubated in an overlay medium containing DMEM supplemented with 2% FBS and 0.9% carboxymethyl cellulose (Calbiochem, USA). Cells were further cultured for 96 h and then fixed with paraformaldehyde (4% in PBS) and stained with crystal violet solution (1% in water. Sigma-aldrich, Germany) for visualizing plaques. Virus titer was calculated in plaque-forming units (PFU) per milliliter. Ideally, the method could detect at least one plaque in 600 μL of the non-diluted sample, the detection limit in this study is 1.67 pfu/ml. That is, 3.33 pfu in the gauze. The S. aureus sterilization experiment was conducted in the Test Center of Antimicrobial Materials, Technical Institute of Physics and Chemistry. The relative humidity in laboratory was in the range of 40–60%. The S. aureus was inoculated from tryptic soy agar plate medium (Beijing Land Bridge Technology Co,. LTD, Beijing, China) stored in 4 °C to a new tryptic soy agar plate medium and was incubated at 37 °C for 24 h for activation. S. aureus suspension was made by inoculating S. aureus from activated tryptic soy agar plate medium into a solution made of 25 mL nutrient broth (Beijing Land Bridge Technology Co,. LTD, Beijing, China), 97.5 mL saline and 2 g Tween (GF, Hong Kong, China). Then the suspension was serially diluted. Then bovine serum albumin (Beijing Solarbio Science & Technology Co., Ltd., Beijing, China) was added to the S. aureus solution to reach concentration of 3%. A drip of 75 μL prepared S. aureus (ATCC 6538) was dropped on the gauze. Subsequently, the samples were treated with the same temperature and HIUVC irradiation condition as those contaminated with SARS-CoV-2. After irradiation, samples of S. aureus were assayed by standard pour plate procedures. The samples were massaged with 10 mL 0.03 M phosphate-buffered saline (pH 7.4, Beijing chemistry industry group Co., Ltd., Beijing, China) and serially diluted with sterile saline solution. Molten plate count agar was poured into petri dish containing 1 mL of diluted sample. The solid medium was incubated at 37 °C for 24 h for plate count. Each experiment with different conditions was repeated 3 times to assure the repeatability. The single-factor analysis of variance and Scheffe’s test were used to test the significant differences among means at p < 0.05. Modelling of Survival Curves The survival curves of SARS-CoV-2 and S. aureus were fitted with four typical models via least-squares regression using GInaFit, a freeware capable of modelling microbial survival (Geeraerd et al., 2005). Four typical models are (1) Weibull model, (2) Biphasic model, (3) log linear-tail model, and (4) log linear model. The Weibull model is described by equation. (Mafart et al., 2002)1 logN=logN0-tαβ, where N is the number of surviving microorganism, cfu/pfu, N0 is the initial number of microorganism, t is ultraviolet exposure time, minute. And α is the time when the microorganism reduces from N0 to N0/10, and β is a shape parameter. The survival curve is downward concave when β > 1 and upward concave when β < 1. The biphasic model (Kowalski, 2009) is described as:2 logN=logN0+logf×e-kmax1×t+1-f×e-kmax2×t, where f is UV resistant fraction. And kmax1 and kmax2 are slopes of the biphasic curves, respectively. They are the rate constant of stage 1 and stage 2, respectively. The log linear model (Kowalski, 2009) is described by equation3 logN=logN0-kmax×tln10, where kmax is the inactivation rate. The log linear-tail model (Geeraerd et al., 2000) is described as:4 logN=log10logN0-10logNres×e-kmax×t+10logNres, where Nres refers to subpopulation. And kmax means the inactivation rate of the linear part of the survival curve. The mean square error (MSE) and regression coefficient (R2) and were analyzed to evaluate the goodness of the fit of the 4 model. Besides, dose of achieving 3 log reduction of microorganism (D3d) by HIUVC treatment of 4 models were computed by the Goal Seek function in Microsoft Excel 365. Results and Discussion The recovery rate of SARS-CoV-2 based was 18.5% under 4 °C and 8.0% under − 20 °C, respectively. The freeze–thaw cycle might cause the reduction of virus titre, resulting in relatively low recovery rate. The recovery rate of S. aureus was approximate 100% for both 4 °C and − 20 °C. Nevertheless, in both the SARS-CoV-2 and the S. aureus experiment, HIUVC showed a high sterilization effect when comparing the treated samples with the non-treated control. The sterilization effect of HIUVC on SARS-CoV-2 under 4 °C and − 20 °C is shown in Fig. 2. Limit of detection was recorded was 3.33 pfu. Degree of 4 °C is the typical storage temperature for chilled foods and − 20 °C for frozen foods. It is shown that the pfu of SARS-CoV-2 decreased with the increase of exposure time under HIUVC. The dose of HIUVC required at least 15.3 mJ/cm2 to reach 3 log reduction. The dose was larger than the liquid virus reported by Sabino et al. (2020) (6.556 mJ/cm2) and Biasin et al. (2021) (5.4 mJ/cm2), which were conducted in room temperature. The larger dose in this study might attribute to the shadowing effects of the gauze compared to the aqueous results. For 4 °C, when exposure time increased from 3 to 5 s, there was no significant reduction (p < 0.05) of SARS-CoV-2 due to the shadow effects of the gauze. In the survival curve fitted by biphasic model showed in Fig. 4b, this trend is clearer. This trend was in accordance with the research conducted by Darnell et al. (2004). They investigated the UVC on SARS-CoV-1, and the results showed that when the UVC dose exceeded a certain value, no additional inactivation was observed. The dose required to achieve 3 log reduction based on biphasic model was 8.9 mJ/cm2 for 4 °C and − 20 °C, which was smaller than those reported by Bormann et al. conducted at room temperature (Bormann et al., 2021). Their results showed that more than 14.7 mJ/cm2 was needed under irradiance of 0.245 mW/cm2 for carriers of glass, metal, and plastic. This difference might attribute to the lower intensity of the LED lamp or the difference of carrier material or temperature between their research and this study.Fig. 2 The sterilization effect of HIUVC on SARS-CoV-2 The comparison of the sterilization effect of HIUVC on S. aureus and SARS-CoV-2 is shown in Fig. 3. The detection limit of S. aureus was 10 cfu. Data group with shared superscript letter indicated the there is no statistical significance between these two groups, otherwise they show statistical significance (p < 0.05). The temperature did not have a significant effect on the HIUVC sterilization of SARS-CoV-2 and S. aureus between − 20 °C and 4 °C (p < 0.05), which is similar to the research on other microbes (Severin et al., 1983). As coronavirus has a simpler structure than bacteria, it might be more vulnerable to HIUVC compared to S. aureus (Khan et al., 2022). The effect is significant when the HIUVC doses were 15.3 mJ/cm2 at 3 s and 25.5 mJ/cm2 at 5 s (p < 0.05).Fig. 3 Comparison of sterilization effect of HIUVC on S. aureus and SARS-CoV-2. Error bars represent standard deviation. The different superscripts indicate the significant difference, p < 0.05 The HIUVC sterilization relation between S. aureus and SARS-CoV-2 was established. Four typical mathematical model were used to fit the microbial survival curves after HIUVC treatment, as shown in Fig. 4. The range of HIUVC treating time was 0–5 s (0–15.5 mJ/cm2). The fit goodness is shown in Table 1. The results showed that biphasic model fitted the survival of S. aureus and SARS-CoV-2 better with larger R2 and lower MSE.Fig. 4 Survival curves of S. aureus and SARS-CoV-2 after HIUVC irradiation: a Weibull model, b biphasic model, c log linear-tail model, d log linear model Table 1 Comparison of fit goodness of different models for survival curves of SARS-CoV-2 and S. aureus Weibull Biphasic Log linear-tail Log linear MSE R2 D3d MSE R2 D3d MSE R2 D3d MSE R2 D3d 4 °C SARS-CoV-2 0.1104 0.9681 12.4 0.0474 0.9878 8.9 0.0577 0.9834 8.7 0.4417 0.8584 19.7 − 20 °C SARS-CoV-2 0.2072 0.9592 9.9 0.0883 0.9846 8.9 0.0921 0.9819 10.3 0.4823 0.8946 15.9 4 °C S. aureus 0.0994 0.9309 0.1092 0.9325 0.1756 0.8780 0.2147 0.8342 − 20 °C S. aureus 0.0811 0.9482 0.0468 0.9734 0.0416 0.9734 0.1037 0.9264 Biphasic model was used to establish the correlation between HIUVC sterilization effect against SARS-CoV-2 and S. aureus on gauze. At the same dose, the log reduction of SARS-CoV-2 and S. aureus were computed based on 101 evenly distributed points between 5.1 and 15.3 mJ/cm2. These data were plotted in Fig. 5. The reduction ranges of S. aureus and SARS-CoV-2 in Fig. 5 were within the range of experimental data. According to the graph, once the sterilization effect of the known HIUVC dose ranging from 5.1 to 15.3 mJ/cm2 against S. aureus on gauze is known, the sterilization effect of the same HIUVC dose against the SARS-CoV-2 on gauze with BSA added under the same temperature can be derived. Therefore, with the help of the sterilization relationship between S. aureus and SARS-CoV-2, S. aureus can be used to detect the sterilization effect of large-scale ultraviolet sterilization equipment at the sterilization site, avoiding the complicated operation of the SARS-CoV-2 and the need for specialized laboratories. It is worth noted that the correlation may not be applicable under the different surface conditions, however, UVC manufacturers could use this method to quantify dose–response curves for SARS-CoV-2 on various surfaces. That is, they could use bacteria to test the UVC sterilization effect based on the correlation with SARS-CoV-2 on various surfaces established in laboratory. The current study chose gauze as microorganism carriers, which can provide a reference to SARS-CoV-2 sterilization on food packages such as plastic, glass, paper, board, and metal under 4 °C and − 20 °C. Porous surfaces required higher doses of ultraviolet than non-porous surfaces to reach same log reduction of SARS-CoV-2 (Tomás et al., 2022). Gauze was a porous carrier, which was more difficult to sterilize than non-porous food packages such as plastic, glass and metal.Fig. 5 HIUVC sterilization correlation between different microorganisms on gauze under different typical cold chain temperature Conclusion This study acquired the sterilization data of HIUVC against the SARS-CoV-2 virus under low-temperature conditions for the first time. The dose of 15.3 mJ/cm2 of HIUVC achieved 3 log reduction of SARS-CoV-2 on gauze under 4 °C and − 20 °C with 3 s. The HIUVC sterilization effect of SARS-CoV-2 did not vary significantly with the change in temperature. HIUVC rapidly sterilized SARS-CoV-2 on gauze under typical cold chain temperature. Also, the sterilization effect of HIUVC on SARS-CoV-2 was compared with S. aureus under low temperatures. Weibull, biphasic, log-linear tail and log linear models were used to fit the survival curves of SARS-CoV-2 and S. aureus. The biphasic model fitted best with R2 of 0.9325–0.9878. The corresponding relation between HIUVC sterilization effect against them was established. These data provide evidence support for the application of HIUVC in cold chain. Moreover, the proposed correlation could provide a method for using bacteria as a substitute to test the sterilization effect of sterilization equipment against SARS-CoV-2, cutting off the spread of COVID-19 through the cold chain. Acknowledgements This study was supported by the National Natural Science Foundation of China (No. 51976232) and the Director's Fund of the Technical Institute of Physics and Chemistry, CAS. Author Contributions Conceptualization: CT; Methodology: HZ, QC; Formal analysis and investigation: PL, XK, DL, XL, WY, HZ; Writing-original draft preparation: PL; Writing-review and editing: XK, HZ; Funding acquisition: CT, HZ; Resources: HX; Supervision: HZ, CT, QC; Project administration: CT; Validation: HX. Data Availability The datasets generated during the current study are available in the Science Data Bank repository, http://doi.org/10.57760/sciencedb.01917 Declarations Conflict of interest The authors have no relevant financial or non-financial interests to disclose. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Peiru Li and Xianliang Ke should be considered joint first author. ==== Refs References Benkeblia N In the landscape of SARS-CoV-2 and fresh fruits and vegetables: The fake and hidden transmission risks Journal of Food Safety 2021 41 4 e12898 10.1111/jfs.12898 34219847 Biasin M Bianco A Pareschi G Cavalleri A Cavatorta C Fenizia C Galli P Lessio L Lualdi M Tombetti E Ambrosi A Redaelli EMA Saulle I Trabattoni D Zanutta A Clerici M UV-C irradiation is highly effective in inactivating SARS-CoV-2 replication Scientific Reports 2021 11 1 6260 10.1038/s41598-021-85425-w 33737536 Bormann M Alt M Schipper L van de Sand L Otte M Meister TL Dittmer U Witzke O Steinmann E Krawczyk A Disinfection of SARS-CoV-2 contaminated surfaces of personal items with UVC-LED disinfection boxes Viruses 2021 13 4 598 10.3390/v13040598 33807470 Chan KH Peiris JSM Lam SY Poon LLM Yuen KY Seto WH The effects of temperature and relative humidity on the viability of the SARS coronavirus Advances in Virology 2011 2011 e734690 10.1155/2011/734690 Chitrakar B Zhang M Bhandari B Improvement strategies of food supply chain through novel food processing technologies during COVID-19 pandemic Food Control 2021 125 108010 10.1016/j.foodcont.2021.108010 33679006 Darnell MER Subbarao K Feinstone SM Taylor DR Inactivation of the coronavirus that induces severe acute respiratory syndrome, SARS-CoV Journal of Virological Methods 2004 121 1 85 91 10.1016/j.jviromet.2004.06.006 15350737 Duan SM Zhao X Wen RF Huang JJ Pi GH Zhang SX Han J Bi SL Ruan L Dong XP Team SR Stability of SARS coronavirus in human specimens and environment and its sensitivity to heating and UV irradiation Biomedical and Environmental Sciences 2003 16 3 246 255 14631830 Fischer R Morris D van Doremalen N Sarchette S Matson MJ Bushmaker T Yinda CK Seifert S Gamble A Williamson B Judson S de Wit E Lloyd-Smith J Munster V Effectiveness of N95 respirator decontamination and reuse against SARS-CoV-2 virus Emerging Infectious Disease Journal 2020 26 9 2253 10.3201/eid2609.201524 Geeraerd AH Herremans CH Van Impe JF Structural model requirements to describe microbial inactivation during a mild heat treatment International Journal of Food Microbiology 2000 59 3 185 209 10.1016/S0168-1605(00)00362-7 11020040 Geeraerd AH Valdramidis VP Van Impe JF GInaFiT, a freeware tool to assess non-log-linear microbial survivor curves International Journal of Food Microbiology 2005 102 1 95 105 10.1016/j.ijfoodmicro.2004.11.038 15893399 Gerchman Y Mamane H Friedman N Mandelboim M UV-LED disinfection of coronavirus: Wavelength effect Journal of Photochemistry and Photobiology b: Biology 2020 212 112044 10.1016/j.jphotobiol.2020.112044 33022467 Guo M Yan J Hu Y Xu L Song J Yuan K Cheng X Ma S Liu J Wu X Liu L Rong S Wang D Transmission of SARS-CoV-2 on cold-chain food: Precautions can effectively reduce the risk Food and Environmental Virology 2022 10.1007/s12560-022-09521-4 35767120 He X Liu X Li P Wang P Cheng H Li W Li B Liu T Ma J A multi-stage green barrier strategy for the control of global SARS-CoV-2 transmission via cold chain goods Engineering 2022 9 13 16 10.1016/j.eng.2021.08.013 34631198 Hu L Gao J Yao L Zeng L Liu Q Zhou Q Zhang H Lu D Fu J Liu QS Li M Zhao X Hou X Shi J Liu L Guo Y Wang Y Ying G-G Cai Y Jiang G Evidence of foodborne transmission of the coronavirus (COVID-19) through the animal products food supply chain Environmental Science & Technology 2021 55 5 2713 2716 10.1021/acs.est.0c06822 33590749 Kariwa H Fujii N Takashima I Inactivation of SARS coronavirus by means of povidone-iodine, physical conditions and chemical reagents Dermatology 2006 212 Suppl. 1 119 123 10.1159/000089211 16490989 Khan M McDonald M Mundada K Willcox M Efficacy of ultraviolet radiations against coronavirus, bacteria, fungi, fungal spores and biofilm Hygiene 2022 2 3 120 131 10.3390/hygiene2030010 Kim C Hung Y-C Inactivation of E. coli O157:H7 on blueberries by electrolyzed water, ultraviolet light, and ozone Journal of Food Science 2012 77 4 M206 M211 10.1111/j.1750-3841.2011.02595.x 22352693 Kowalski W Ultraviolet germicidal irradiation handbook: UVGI for air and surface disinfection Springer 2009 10.1007/978-3-642-01999-9 Lin X Ke X Jian X Xia L Yang Y Zhang T Xiong H Zhao B Liu W Chen Q Tang C Azacytidine targeting SARS-CoV-2 viral RNA as a potential treatment for COVID-19 Science Bulletin 2022 67 10 1022 1025 10.1016/j.scib.2022.02.002 35186363 Liu H Fei C Chen Y Luo S Yang T Yang L Liu J Ji X Wu W Song J Investigating SARS-CoV-2 persistent contamination in different indoor environments Environmental Research 2021 202 111763 10.1016/j.envres.2021.111763 34329634 Lu L-C Quintela I Lin C-H Lin T-C Lin C-H Wu VCH Lin C-S A review of epidemic investigation on cold-chain food-mediated SARS-CoV-2 transmission and food safety consideration during COVID-19 pandemic Journal of Food Safety 2021 41 6 e12932 10.1111/jfs.12932 34898751 Mafart P Couvert O Gaillard S Leguerinel I On calculating sterility in thermal preservation methods: Application of the Weibull frequency distribution model International Journal of Food Microbiology 2002 72 1 107 113 10.1016/S0168-1605(01)00624-9 11843401 Minamikawa T Koma T Suzuki A Mizuno T Nagamatsu K Arimochi H Tsuchiya K Matsuoka K Yasui T Yasutomo K Nomaguchi M Quantitative evaluation of SARS-CoV-2 inactivation using a deep ultraviolet light-emitting diode Scientific Reports 2021 11 1 5070 10.1038/s41598-021-84592-0 33658595 National Health Commission of the People's Republic of China. (2020a). Work Plan on the Preventive Comprehensive Sterilization of Imported Cold Chain Food. http://www.nhc.gov.cn/cms-search/xxgk/getManuscriptXxgk.htm?id=26b2fafc696b48e3b2dab5cdb2fd50d9 National Health Commission of the People's Republic of China. (2020b). Technical Guidelines for Prevention, Control and Sterilization on of Coronavirus in the Production and Operation Process of Cold Chain Food. http://www.nhc.gov.cn/cms-search/xxgk/getManuscriptXxgk.htm?id=ff228979f1534c3abca56559f14ea115 Pang X Ren L Wu S Ma W Yang J Di L Li J Xiao Y Kang L Du S Du J Wang J Li G Zhai S Chen L Zhou W Lai S Gao L Pan Y COVID-19 Laboratory Testing Group Cold-chain food contamination as the possible origin of COVID-19 resurgence in Beijing National Science Review 2020 7 12 1861 1864 10.1093/nsr/nwaa264 34676083 Qian J Yu Q Jiang L Yang H Wu W Food cold chain management improvement: A conjoint analysis on COVID-19 and food cold chain systems Food Control 2022 137 108940 10.1016/j.foodcont.2022.108940 35261485 Raeiszadeh M Adeli B A critical review on ultraviolet disinfection systems against COVID-19 outbreak: Applicability, validation, and safety considerations ACS Photonics 2020 7 11 2941 2951 10.1021/acsphotonics.0c01245 Sabino CP Sellera FP Sales-Medina DF Machado RRG Durigon EL Freitas-Junior LH Ribeiro MS UV-C (254 nm) lethal doses for SARS-CoV-2 Photodiagnosis and Photodynamic Therapy 2020 32 101995 10.1016/j.pdpdt.2020.101995 32916328 Severin BF Suidan MT Engelbrecht RS Effect of temperature on ultraviolet light disinfection Environmental Science & Technology 1983 17 12 717 721 10.1021/es00118a006 22283127 Storm N McKay LGA Downs SN Johnson RI Birru D de Samber M Willaert W Cennini G Griffiths A Rapid and complete inactivation of SARS-CoV-2 by ultraviolet-C irradiation Scientific Reports 2020 10 1 22421 10.1038/s41598-020-79600-8 33380727 Tomás AL Reichel A Silva PM Silva PG Pinto J Calado I Campos J Silva I Machado V Laranjeira R Abreu P Mendes P Sedrine NB Santos NC UV-C irradiation-based inactivation of SARS-CoV-2 in contaminated porous and non-porous surfaces Journal of Photochemistry and Photobiology b: Biology 2022 10.1016/j.jphotobiol.2022.112531 35933836 Trivellin N Buffolo M Onelia F Pizzolato A Barbato M Orlandi VT Del Vecchio C Dughiero F Zanoni E Meneghesso G Crisanti A Meneghini M Inactivating SARS-CoV-2 using 275 nm UV-C LEDs through a spherical irradiation box: Design, characterization and validation Materials 2021 14 9 2315 10.3390/ma14092315 33946929 Trivellin N Piva F Fiorimonte D Buffolo M De Santi C Orlandi VT Dughiero F Meneghesso G Zanoni E Meneghini M UV-based technologies for SARS-CoV2 inactivation: Status and perspectives Electronics 2021 10 14 1703 10.3390/electronics10141703 WHO. (2022). World Health Organization. https://covid19.who.int/, Accessed 21 July 2022. Zhao H Liu S Tian C Yan G Wang D An overview of current status of cold chain in China International Journal of Refrigeration 2018 88 483 495 10.1016/j.ijrefrig.2018.02.024
PMC009xxxxxx/PMC9996552.txt	==== Front Spine Deform Spine Deform Spine Deformity 2212-134X 2212-1358 Springer International Publishing Cham 36892744 664 10.1007/s43390-023-00664-3 Case Series Thoracolumbar curve behavior after selective thoracic anterior vertebral body tethering in Lenke 1A vs Lenke 1C curve patterns http://orcid.org/0000-0002-9422-6849 Welborn Michelle Cameron [email protected] 1 Blakemore Laurel 12 Handford Cameron 13 Miyanji Firoz 14 Parent Stefan 15 El-Hawary Ron 16 1 3101 SW Sam Jackson Park Road, Portland, OR 97229 USA 2 CEO, Pediatric Specialists of Virginia, Fairfax, VA USA 3 grid.412703.3 0000 0004 0587 9093 Department of Orthopaedics, Royal North Shore Hospital, St. Leonards, NSW Australia 4 grid.414137.4 0000 0001 0684 7788 Department of Orthopedics, British Columbia Children’s Hospital, Vancouver, Canada 5 grid.411418.9 0000 0001 2173 6322 Département de Chirurgie, Sainte-Justine University Hospital Center, Université de Montréal, 3175 Côte-Sainte-Catherine, Montreal, Canada 6 grid.414870.e 0000 0001 0351 6983 Department of Surgery, IWK Health Centre Dalhousie University, Halifax, Canada 9 3 2023 2023 11 4 897907 9 11 2022 4 2 2023 © The Author(s), under exclusive licence to Scoliosis Research Society 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Study design Retrospective review of a prospective database. Objectives The purpose of this study is to evaluate changes in the thoracic and thoracolumbar/lumbar curves and truncal balance in patients treated with selective thoracic anterior vertebral body tethering (AVBT) with Lenke 1A vs 1C curves at a minimum of 2 years follow-up. Summary Lenke 1C curves treated with selective thoracic AVBT demonstrate equivalent thoracic curve correction and reduced thoracolumbar/lumbar curve correction compared to Lenke 1A curves. Additionally, at the most recent follow-up, both curve types demonstrate comparable coronal alignment at C7 and the lumbar curve apex, though 1C curves have better alignment at the lowest instrumented vertebra (LIV). Rates of revision surgery are equivalent between the two groups. Methods A matched cohort of 43 Risser 0-1, Sanders Maturity Scale (SMS) 2-5 AIS pts with Lenke 1A (1A group)and 19 pts with Lenke 1C curves (1C group) treated with selective thoracic AVBT and a minimum of 2-year follow-up were included. Digital radiographic software was used to assess Cobb angle and coronal alignment on preoperative, postoperative and subsequent follow-up radiographs. Coronal alignment was assessed by measuring the distance from the center sacral vertical line (CSVL) to the midpoint of the LIV, apical vertebra for thoracic and lumbar curves and C7. Results There was no difference in the thoracic curve measured preoperatively, at first erect, pre-rupture or at the most recent follow-up, nor was there a significant difference in C7 alignment (p = 0.057) or apical thoracic alignment (p = 0.272) between the 1A and 1C groups. Thoracolumbar/lumbar curves were smaller in the 1A group at all-time points. However, there was no significant difference between the percent correction between the two groups thoracic (p = 0.453) and thoracolumbar/lumbar (p = 0.105). The Lenke 1C curves had improved coronal translational alignment of the LIV at the most recent follow-up p = 0.0355. At the most recent follow-up the number of patients considered to have successful curve correction (Cobb angle correction of both the thoracic and thoracolumbar//lumbar curves to ≤ 35 degrees), was equivalent between Lenke 1A and Lenke 1C curves (p = 0.80). There was also no difference in the rate of revision surgery between the two groups (p = 0.546). Conclusion This is the first study to compare the impact of lumbar curve modifier type on outcomes in thoracic AVBT. We found that Lenke 1C curves treated with selective thoracic AVBT demonstrate less absolute correction of the thoracolumbar/lumbar curve at all time points but have equivalent percent correction of the thoracic and thoracolumbar/lumbar curves. The two groups have equivalent alignment at C7 and the thoracic curve apex, and Lenke 1C curves have better alignment at the LIV at the most recent follow-up. Furthermore, they have an equivalent rate of revision surgery compared to Lenke 1A curves. Selective thoracic AVBT is a viable option for selective Lenke 1C curves, but despite equivalent correction of the thoracic curve, there is less correction of the thoracolumbar/lumbar curve at all-time points. Keywords Vertebral body tethering Growth modulation Compensatory curve Alignment Thoracolumbar/lumbar Thoracic Scoliosis issue-copyright-statement© Scoliosis Research Society 2023 ==== Body pmcIntroduction The treatment of Lenke 1C curves has long been controversial. Historically only 62% were treated with selective thoracic fusion [1]. Nonselective fusion resulted in increased blood loss, longer operative times, decreased range of motion and increased rates of distal disc degeneration [2–4]. The principle of selective thoracic fusion was advanced by Lenke who proposed this was best performed in patients with thoracic to lumbar Cobb angle, Apical Vertebral Rotation (AVR) and Apical Vertebral Translation (AVT) ratios of greater than 1.2 [5]. These criteria were further refined by Newton et al., who initially proposed limited thoracic curve correction so that the thoracic and thoracolumbar/lumbar curves could balance each other and minimize the risk of coronal decompensation [6]. It was subsequently shown that the uninstrumented curve corrected to match the instrumented curve and thus maximal correction of the thoracic curve is now sought to maximize the correction of the compensatory thoracolumbar/lumbar curve [7]. Just as fusion techniques have significantly evolved for Lenke 1C curves, so have non-fusion techniques. Anterior vertebral body tethering (AVBT) is a new and emerging technology which early results have shown may result in motion preservation [8]. As for any new treatment approach, the outcomes must be compared to the existing techniques, in this case selective thoracic fusion. Early reports for AVBT describe a high revision rate, which ranges from 12.3 to 60% [9–12], suggesting that the learning curve and best application for this technology are still being refined [13, 14]. Appropriate patient selection continues to be controversial. Several studies have attempted to delineate optimal skeletal maturity with Shin et al. showing skeletal immaturity was the number one reason for AVBT revision due to overcorrection, while Newton et al. showed that advanced skeletal maturity was associated with higher rates of revision to a fusion. The concept importance of sufficient remaining growth was recently reinforced by Alanay et al. who reported on the variable rates of growth and remodeling in AVBT associated with different SMS scores [9, 12, 15]. However, skeletal maturity is only one of many factors that will help define the ideal patient selection. To date, the impact of different lumbar curve modifiers on the outcomes of thoracic AVBT has not been examined. In this study, we evaluated the impact of AVBT on the instrumented thoracic and uninstrumented thoracolumbar/lumbar curves as well as on their C7, apical and LIV coronal alignment based in Lenke 1A vs Lenke 1C curve types. Methods This was a retrospective study of a prospective multi-center registry of idiopathic scoliosis patients with Lenke 1A or 1C curvatures that underwent selective thoracic AVBT between 2013 and 2018. Institutional review board (IRB) approval was obtained at each site. We included all patients who were Risser stage 0–3 and/or SMS 2–5 and in whom the LIV of L1 or higher, with a minimum 2-year follow-up. We specifically excluded Lenke 1B curves as we wanted to highlight potential differences in the correction or lack of correction of the uninstrumented thoracolumbar/lumbar curve. Preoperative demographic data included age, sex, ethnicity, etiology, prior treatment and body mass index (BMI). Digital radiographic software was used to assess major and minor Cobb angle, and curve flexibility preoperatively, postoperatively and on subsequent follow-up images. Postoperative evaluation also included suspected presence or absence of tether rupture (defined as an increase in Cobb angle of > 5 degrees between two adjacent vertebral body screws compared with previous radiographs), maximum Cobb angle correction, disc wedging below the LIV and coronal alignment at most recent follow-up [16]. Coronal alignment was assessed by measuring the distance from the CSVL to the midpoint of the LIV, the apical vertebra of each curve and C7. Primary outcomes included the need for secondary surgery and major and minor Cobb angle magnitude. Secondary outcomes included tether breakage, coronal balance and sub-adjacent disc wedging. Two-way comparisons were made between the Lenke 1A and Lenke 1C groups. Ratios were tested using Fisher’s Exact test. Means were compared using the two-tailed t test or if the variances were unequal a Mann–Whitney U test was used. Statistical significance was set at a p value < 0.05 and clinical significance was set at a difference in Cobb magnitude > 5 degrees. All statistics were done using SPSS. Results 111 patients were eligible for inclusion, 62 patients met the inclusion criteria, of whom 43 were Lenke 1A and 19 were Lenke 1C, and 49 were excluded due to incomplete data or inadequate follow-up. Complete demographics are listed in Table 1. There was no difference in the average follow-up between the groups with an average of 3.0 years in the 1A group and 3.0 years in the 1C group. Neither was there a difference in the age at index procedure of 13.2 years old (9.8–17.2) in the 1A group vs 13.7 (11.7–16.0) in the 1 C group) or the rate of revision surgery (one patient in each group with an insufficient correction that was revised to a fusion).Table 1 Demographics/outcomes for Lenke 1A and Lenke 1C curves Demographics/outcomes p value Lenke 1A Lenke 1C n = 43 n = 19 Ave follow-up months 35.7 35.5 0.930 Age at index procedure 13.2 (9.8–17.2) 13.7 (11.7–16.0) 0.247 Rate of tether rupture 20/43 (46.5%) 11/19 (57.9%) 0.40856 Revision rate/reason 1/43 2% 1/19 5% 0.546 Insufficient correction revised to fusion (initial thoracic curve correction to 48°, prerupture 45° postrupture 65°) Insufficient correction revised to fusion (initial thoracic curve correction to 51°, prerupture 50° postrupture 50°) Preoperative measures There was no difference in the preoperative thoracic Cobb angle between the two groups, with an average of 48° (32–79) in the Lenke 1A and 50° (39–60) in the Lenke 1C patients (p = 0.446). However, there was a difference in the preoperative thoracolumbar/lumbar curve magnitude with the Lenke 1A curves averaging 31° (22–44) and the Lenke 1C 40° (30–53) (p < 0.00001). Regarding curve flexibility, the Lenke 1C curves showed increased thoracic curve percent correction on flexibility films 42% (1–77%) vs 55% (29–90) (p = 0.0172). Whereas there was no difference in the thoracolumbar/lumbar percent correction on flexibility films in 65% (11–146) vs 61% (26–97) (p = 0.4902). Postoperative curve measurements There was no difference in the first erect thoracic curve magnitude, with the Lenke 1A measuring 27° (10–48) vs the Lenke 1C 30° (16–51) p = 0.193. There was, however, a difference in the first erect thoracolumbar/lumbar Cobb magnitude with the Lenke 1A averaging 19° (4–32) vs Lenke 1C 26° (14–45) p < 0.005. There was no difference in the maximal Cobb angle correction prior to suspected tether rupture or at the most recent follow-up (in patients with no identifiable tether rupture), with an average thoracic curve magnitude in the Lenke 1A group of 19° (− 34 to 53) and the Lenke 1C of 22° (5–50) p = 0.459. There was a suspected rupture in half of all patients (31/62), but no difference in the rate of rupture between the two groups (20/43 Lenke 1A and 11/19 Lenke 1C patients p = 0.40856). Post-rupture and at the most recent follow-up there was no difference in thoracic Cobb angle in the Lenke 1A vs the Lenke 1C groups [24° (− 34 to 65) vs 29° (5–50) p = 0.322] at the most recent follow-up. There was also no difference in the loss of correction in the thoracic curve after tether rupture in the Lenke 1A vs the Lenke 1C [5° (− 2 to 34) vs 7° (0–19) p = 0.738] or disc angulation below the LIV, [3° (0–9) vs 3° (0–8) p = 0.840] at most recent follow-up. Furthermore, there was no difference in the percent curve corrections from preop to the most recent follow-up for the thoracic curve or the thoracolumbar/lumbar curve, with a percent curve correction in the thoracic curve for the Lenke 1A group of 52% (− 19 to 174) vs the Lenke 1C group of 44% (14–88) (p = 0.45326). Similarly, there was no difference in the thoracolumbar/lumbar curve percent curve correction for the Lenke 1A group at the final follow-up of 41% (− 10 to 96) vs the Lenke 1C group of 32% (− 9 to 76) (p = 0.10524). Complete data is shown in Table 2.Table 2 Pre-operative, post-operative and most recent follow-up Cobb angle measurements Lenke 1A Lenke 1C p values n = 43 n = 19 Thoracic curve Thoracolumbar curve Thoracic curve Thoracolumbar curve Thoracic curve Thoracolumbar curve Preoperative 48 (32–79) 31 (22–44) 50 (39–60) 40 (30–53) 0.446 < 0.00001 Percent correction on flexibility films 42% (1–77%) 65% (11–146) 55% (29–90) 61% (26–97) 0.0172 0.4902 Initial postoperative 27 (10–48) 19 (4–32) 30 (16–51) 26 (14–45) 0.193 0.00367 Pre rupture* 19 (− 34 to 53) na 22 (5–50) na 0.459 na Most recent** 24 (− 34 to 65) 19 (1–35) 29 (5–50) 28 (8–42) 0.322 0.000124 Change in curve after tether rupture 5 (− 2 to 34) na 1C 7 (0–19) na 0.738 na Percent curve change from preoperative to most recent 52% (− 19 to 174) 41% (− 10 to 96) 44% (14–88) 32% (− 9 to 76) 0.45326 0.10524 Maximal correction prior to tether rupture if tether rupture identified *Most recent follow-up Coronal alignment As seen in Table 3, there was no difference in the coronal alignment at C7, with the Lenke 1A deviating 8 mm (1–26) from the CSVL vs 2 mm for Lenke 1C (− 23 to 27) (p = 0.057), nor in the thoracolumbar/lumbar apical vertebral translation from the CSVL in Lenke 1A 20 mm (− 16 to 58) vs Lenke 1C 14 mm (− 16 to 56) p = 0.272 at most recent follow-up. However, there was a difference in alignment at the LIV, with less deviation from the midline in the Lenke 1C group [7 mm (− 13 to 31)] vs the Lenke 1A group [12 mm (− 13 to 47)] (p = 0.0355). Figure 1 demonstrates an example of two patients with thoracolumbar/lumbar curves of less than 35 degrees, one where the LIV is well aligned and one where the LIV is poorly aligned.Table 3 Coronal measurements at latest follow-up Level Lenke 1A Lenke 1C p value n = 43 n = 19 C7 8 (1–26) 2 (− 23 to 27) 0.057 Apical 20 (− 16 to 58) 14 (− 16 to 56) 0.272 LIV 12 (− 13 to 47) 7 (− 13 to 31) 0.0355 Disc angulation below LIV 3 (0–9) 3 (0–8) 0.840 Fig. 1 Two curves with Thoracic Scoliosis < 35 at 4.4 years and 3.5 years follow-up, respectively. Patient on the left preop and most recent follow-up with alignment < 1.5 cm at the curve apex and LIV. Pt on the right with alignment > 1.5 cm at curve apex and LIV Outcomes at a most recent follow-up At the most recent follow-up there was no difference in the number of patients with good correction, defined as both the thoracic and thoracolumbar/lumbar curves measuring ≤ 35 degrees, (33/43 Lenke 1A and 14/19 Lenke 1C curves, p = 0.80) (Tables 4 and 5 for Summary of all data for Lenke 1A and 1C curves). The Lenke 1A group corrected an additional 7% (− 66 to 118%) in the thoracic and 3% (− 55 to 53%) in the thoracolumbar/lumbar spine from the first upright. The Lenke 1C group corrected an additional 4% (− 16 to 35%) in the thoracic spine and 5% (− 19 to 33%) in the thoracolumbar/lumbar spine. There was a strong correlation between the rate of correction for the instrumented thoracic and the compensatory thoracolumbar curves/lumbar, with the Spearman’s Rho r = 0.6206 p = 0.00001 for the Lenke 1A and r = 0.81713 p = 0 for the Lenke 1C group. Figure 2 shows patients with similar preoperative curves but differing radiographic outcomes at the most recent follow-up.Table 4 Summary of Lenke 1A data Lenke 1A Curves PT # Demographic Instrumented levels Major curve coronal plane Minor curve coronal plane Sagittal plane Most recent alignment Age at index surgery Sex Duration of follow-up (days) Curve type VBT UIV level VBT LIV level LIV Pre-index T Cobb T cobb flex Post-index T Cobb Initial % T curve correction Pre rupture T Cobb Most recent/ pre-definitive T Cobb Degree Most recent % T curve correction Tether rupture level Change in Cobb after rupture Pre-index TL Cobb Degree Pre-index TL cobb flex Post-index TL Cobb Degree Initial % TL cobb correction Most recent/ pre-definitive TL Cobb Degree Most recent % TL cobb correction Pre-index Sagittal Kyphosis Degree Post-index Sagittal Kyphosis Degree Most recent/pre-definitive Sagittal Kyphosis Degree C7 alignment mm Apex alignment mm Liv alignment mm Disc angulation below LIV 1 12.5 F 1103.0 1AL T4 T12 EV 61.0 32.0 34.0 44.3 24.0 32.0 47.5 t8–9 8.0 39.0 10.0 26.0 33.3 22.0 43.6 11.0 43.0 42.0 9.7 12.0 9.2 4.0 2 17.2 F 778.0 1AL T6 T11 EV 43.0 26.0 34.0 20.9 27.0 27.0 37.2 no 32.0 7.0 31.0 3.1 26.0 18.8 25.0 21.0 7.6 3 13.2 F 1254.0 1AL T5 T11 EV 43.0 26.0 17.0 60.5 7.0 19.0 55.8 t9–10 12.0 22.0 14.0 36.4 12.0 45.5 53.0 11.9 9.9 9.3 2.9 4 13.7 F 1156.0 1AL T6 T11 EV 40.0 26.0 24.0 40.0 23.0 23.0 42.5 no 27.0 13.0 17.0 37.0 16.0 40.7 53.0 33.0 77.0 23.0 13.6 9.4 2.4 5 16.1 F 1105.0 1AL T5 T12 EV 45.0 22.0 16.0 64.4 12.0 12.0 73.3 no 28.0 2.5 13.0 53.6 12.0 57.1 35.0 56.0 5.1 9.1 0.5 0.9 6 14.3 F 1147.0 1AR T5 T12 EV 58.0 38.0 25.0 56.9 21.0 27.0 53.4 T11–12 6.0 35.0 16.0 22.0 37.1 24.0 31.4 36.0 41.0 28.0 8.5 5.0 −5.0 1.3 7 15.2 F 1084.0 1AL T7 T12 EV 40.0 35.0 16.0 60.0 21.0 21.0 47.5 no 31.0 16.0 48.4 22.0 29.0 43.0 41.0 33.0 18.0 0.0 −4.0 0.6 8 14.5 M 1293.0 1AR T5 T12 EV 52.0 20.0 24.0 53.8 28.0 37.0 28.8 t11–12 9.0 35.0 18.0 10.0 71.4 21.0 40.0 33.0 39.0 25.0 3.3 37.0 46.0 7.2 9 14.9 F 1161.0 1AL T6 T12 EV 42.0 25.0 40.5 20.0 20.0 52.4 no 27.0 12.0 19.0 29.6 19.0 29.6 21.0 21.0 11.0 6.7 19.5 17.1 8.8 10 13.9 F 818.0 1ar T6 L1 ev 46.0 25.0 16.0 65.2 −13.0 −13.0 128.3 no 24.0 −11.0 10.0 58.3 9.0 62.5 41.0 36.0 4.0 15.9 13.0 0.5 11 12.9 F 657.0 1al T5 T12 ev 52.0 29.0 10.0 80.8 9.0 9.0 82.7 no 38.0 10.0 6.0 84.2 15.0 60.5 46.0 64.0 11.9 9.4 −13.2 3.8 12 14.0 M 741.0 1al T5 T12 ev 49.0 30.5 22.0 55.1 17.0 23.0 53.1 t9–10 6.0 29.0 6.0 13.0 55.2 15.0 48.3 40.0 41.0 6.0 −12.1 6.6 1.8 13 12.2 F 587.0 1AR T5 T12 ev-1 40.0 15.0 18.0 55.0 −29.0 −29.0 172.5 no 29.0 2.0 12.0 58.6 23.0 20.7 25.0 23.0 4.3 −15.9 4.8 6.6 14 14.4 F 1612.0 1AR T6 L1 EV 60.0 42.0 34.0 43.3 35.0 44.0 26.7 t10–11 9.0 38.0 23.0 31.0 18.4 35.0 7.9 48.0 35.0 23.0 0.3 15 13.1 F 1849.0 1ar T5 T12 ev-1 57.0 35.0 30.0 47.4 23.0 23.0 59.6 no 27.0 7.5 17.0 37.0 22.0 18.5 31.0 19.0 26.0 16.0 55.9 8.4 16 12.9 F 1624.0 1ar ev 79.0 52.0 48.0 39.2 45.0 64.6 18.2 19.6 42.0 37.0 24.0 42.9 17.0 59.5 37.0 41.0 1.8 17 13.9 F 1710.0 1ar T4 T11 ev-1 59.0 35.0 41.0 30.5 53.0 53.0 10.2 no 29.0 6.0 16.0 44.8 32.0 −10.3 27.0 25.0 36.0 8.0 58.3 43.1 3.0 18 12.6 F 1129.0 1al T5 T11 EV 53.0 46.4 37.0 30.2 29.0 29.0 45.3 no 35.0 11.0 26.0 25.7 24.0 31.4 42.0 31.0 34.0 1.2 19 12.8 F 1100.0 1ar T6 T12 ev 56.0 28.6 31.0 44.6 18.3 27.0 51.8 t9-10 8.7 26.0 1.0 28.0 −7.7 26.0 0.0 31.0 21.0 21.0 2.6 20 12.2 F 1129.0 1al T5 T12 ev 40.0 21.1 21.0 47.5 13.0 13.0 67.5 no 25.0 9.6 18.0 28.0 11.0 56.0 30.0 36.0 37.0 2.1 21 12.1 F 1548.0 1ar T5 T12 ev-1 55.0 47.0 27.0 50.9 30.0 30.0 45.5 no 31.0 25.0 20.0 35.5 20.0 35.5 27.0 16.0 36.0 13.6 34.9 20.4 2.3 22 13.9 F 1346.0 1al T6 L1 ev 45.0 29.0 15.0 66.7 9.0 9.0 80.0 no 29.0 18.5 14.0 51.7 9.0 69.0 40.0 41.0 55.0 4.6 12.8 3.6 0.7 23 15.1 F 1465.0 1al T5 T12 ev 48.0 47.6 29.0 39.6 19.0 32.0 33.3 t8–9 13.0 38.0 15.0 25.0 34.2 24.0 36.8 21.0 26.0 49.0 3.0 28.8 9.9 1.2 24 13.1 F 1157.0 1al T5 T12 ev 35.0 13.0 62.9 10.0 10.0 71.4 no 25.0 5.0 80.0 1.0 96.0 23.0 21.0 18.0 1.7 25 12.0 F 1297.0 1al T6 T12 ev 41.0 17.6 25.0 39.0 23.0 42.0 −2.4 t10–11 19.0 25.0 8.0 19.0 24.0 24.0 4.0 22.0 19.0 42.0 0.5 30.5 21.9 2.7 26 12.2 F 734.0 1ar T6 T12 ev 32.0 19.0 14.0 56.3 11.0 20.0 37.5 t11–12 9.0 22.0 6.0 4.0 81.8 14.0 36.4 10.0 16.0 0.0 3.1 27 14.1 F 1211.0 1ar T6 T12 ev 50.0 46.0 27.0 46.0 15.0 19.0 62.0 t9–10 4.0 29.0 8.5 21.0 27.6 14.0 51.7 30.0 32.0 59.0 1.7 15.3 6.1 0.1 28 15.0 F 1346.0 1al T6 L1 ev + 1 47.0 27.5 25.0 46.8 22.3 56.0 −19.1 t8–9, t10–11 33.7 37.0 1.0 24.0 35.1 33.0 10.8 20.0 29.0 49.0 0.5 49.3 27.1 2.3 29 12.2 F 1030.0 1ar T5 T12 55.0 39.0 29.1 33.0 40.0 27.3 t11–12 7.0 38.0 30.0 21.1 23.0 39.5 26.0 30.0 0.0 1.0 30 12.3 F 1177.0 1al T5 T12 ev 45.0 23.0 25.0 44.4 23.0 37.0 17.8 T7–8, T8–9 14.0 34.0 17.0 23.0 32.4 25.0 26.5 28.0 18.0 61.0 2.9 22.1 13.3 4.0 31 11.4 F 1219.0 1ar T5 T12 ev 46.0 20.0 20.0 56.5 −34.0 −34.0 173.9 no 33.0 2.0 16.0 51.5 14.0 57.6 23.0 21.0 40.0 6.4 39.3 30.5 2.4 32 12.1 F 1261.0 1ar T7 L1 ev 46.0 30.0 32.0 30.4 35.0 35.0 23.9 no 35.0 18.0 32.0 8.6 29.0 17.1 25.0 13.0 41.0 26.0 39.0 25.0 5.0 33 11.6 F 1201.0 1ar T6 L1 ev 44.0 21.0 26.0 40.9 25.0 25.0 43.2 t10–11 0.0 27.0 14.0 11.0 59.3 13.0 51.9 28.0 28.0 65.0 7.8 26.2 8.7 0.3 34 12.7 F 729.0 1al T5 T11 ev 36.0 26.0 33.0 8.3 19.0 19.0 47.2 no 34.0 25.0 23.0 32.4 12.0 64.7 48.0 55.0 1.0 35 13.6 F 1246.0 1ar T6 T12 ev 50.0 28.0 32.0 36.0 24.0 46.0 8.0 t10–11, 11–12 22.0 25.0 8.0 20.0 20.0 22.0 12.0 26.0 12.0 38.0 8.7 54.2 47.2 3.6 36 11.2 F 828.0 1ar T6 T12 ev 40.0 16.0 20.0 50.0 8.0 8.0 80.0 no 24.0 10.0 16.0 33.3 4.0 83.3 3.0 13.0 6.0 −9.0 4.0 1.4 37 9.8 F 1003.0 1ar T5 L1 ev + 1 51.0 15.0 30.0 41.2 12.0 12.0 76.5 no 33.0 7.0 16.0 51.5 12.0 63.6 30.0 16.0 13.0 2.0 15.0 2.0 3.1 38 11.2 F 812.0 1al T5 T12 ev 67.0 17.0 32.0 52.2 23.0 27.0 59.7 t9–10 4.0 44.0 7.0 26.0 40.9 23.0 47.7 43.0 33.0 15.1 7.3 3.9 6.1 39 10.8 F 742.0 1ar T5 T12 ev 64.0 15.0 41.0 35.9 28.0 26.0 59.4 t10–11 −2.0 41.0 11.0 30.0 26.8 19.0 53.7 43.0 40.0 14.1 27.3 10.6 0.6 40 14.6 F 751.0 1al T6 T12 ev 42.0 23.0 27.0 35.7 24.0 24.0 42.9 no 30.0 19.0 26.0 13.3 18.0 40.0 12.0 22.0 8.9 4.8 5.5 0.1 41 13.7 M 499.0 1ar T5 T12 ev 42.0 32.0 34.0 19.0 27.0 31.0 26.2 t8–9 4.0 28.0 21.0 20.0 28.6 12.0 57.1 21.0 20.0 2.6 31.6 15.4 0.0 42 14.1 F 882.0 1ar T5 T12 ev 48.0 26.0 28.0 41.7 −12.0 −12.0 125.0 no 32.0 12.0 24.0 25.0 7.0 78.1 18.0 13.0 15.0 5.0 2.0 1.0 2.0 43 13.6 F 483.0 1ar T6 T12 ev 51.0 21.0 36.0 29.4 29.0 36.0 29.4 t11–12 7.0 33.0 12.0 24.0 27.3 25.0 24.2 26.0 18.0 54.0 3.0 21.1 −11.3 0.7 Ave: 13.2 1093.1 48.7 28.3 26.8 45.1 18.3 23.2 53.6 10.1 31.3 11.4 19.5 38.1 18.6 40.7 29.6 28.5 36.7 8.1 20.3 11.9 2.6 Italic values: Underwent revision to fusion Bold values have curves over 50 degrees but have not yet undergone revision surgery T thoracic, TL thoracolumbar/lumbar, Flex flexibility, EV end vertebra Table 5 Summary of Lenke 1C data Lenke 1C Curves PT # Demographic Instrumented levels Major curve coronal plane Minor curve coronal plane Sagittal plane Most recent alignment Age at index surgery Sex Duration of follow-up (days) Curve type VBT UIV Level VBT LIV Level LIV Pre-index T Cobb T cobb flex Post-index T Cobb Initial % T curve correction Pre rupture T Cobb Most recent/ pre-definitive T Cobb Degree Most recent % T curve correction Tether rupture level Change in Cobb after rupture Pre-index TL Cobb Degree Pre-index TL cobb flex Post-index TL Cobb Degree Initial % TL cobb correction Most recent/ pre-definitive TL Cobb Degree Most recent % TL cobb correction Pre-index Sagittal Kyphosis Degree Post-index Sagittal Kyphosis Degree Most recent/pre-definitive Sagittal Kyphosis Degree C7 alignment mm Apex alignment mm Liv alignment mm Disc angulation below LIV 1 13.8 F 1194.0 1c T5 T12 EV 60.0 36.0 40.0 27.0 34.0 43.3 t11–12 7.0 46.0 30.0 34.8 32.0 30.4 49.0 16.0 53.0 0.2 2 14.6 F 1451.0 1 CN T6 T12 EV 58.0 40.0 34.0 41.4 23.0 38.0 34.5 t7–8 15.0 45.0 25.0 28.0 37.8 36.0 20.0 34.0 45.0 45.0 −15.5 20.5 1.7 2.0 3 14.3 M 1126.0 1C T6 T12 EV 47.0 13.0 32.0 31.9 14.0 33.0 29.8 t7–8, 10–11 19.0 30.0 17.0 26.0 13.3 26.0 13.3 16.0 16.0 12.7 36.5 19.6 2.5 4 12.7 F 1418.0 1C T4 T12 EV 50.0 28.0 30.0 40.0 20.0 29.0 42.0 t11–12 9.0 40.0 9.0 29.0 27.5 28.0 30.0 46.0 40.0 60.0 −22.2 14.7 −9.7 2.5 5 14.0 F 1084.0 1C T6 T11 EV 39.0 23.0 16.0 59.0 14.0 14.0 64.1 34.0 25.0 14.0 58.8 11.0 67.6 19.0 30.0 53.0 19.2 6.0 9.8 1.7 6 15.2 F 1086.0 1C T5 T11 EV 58.0 39.0 35.0 39.7 25.0 43.0 25.9 t10–11 18.0 46.0 20.0 31.0 32.6 38.0 17.4 42.0 41.0 66.0 2.0 21.0 5.6 2.1 7 11.7 F 946.0 1C T5 T11 EV 59.0 42.0 36.0 39.0 25.0 35.0 40.7 t10–11 10.0 43.0 13.0 29.0 32.6 33.0 23.3 54.0 34.0 48.0 −11.8 12.6 −20.5 2.8 8 12.1 F 1182.0 1C T5 T11 EV 50.0 36.0 24.0 52.0 16.0 32.0 36.0 t9–10 16.0 37.0 24.0 19.0 48.6 25.0 32.4 25.0 25.0 72.0 2.0 16.0 10.0 3.0 9 12.7 F 887.0 1C T5 T11 EV 55.0 24.0 31.0 43.6 26.0 37.0 32.7 t9–10 11.0 46.0 8.0 20.0 56.5 35.0 23.9 35.0 32.0 43.0 −22.5 13.5 −11.7 4.8 10 16.0 F 832.0 1C T5 T11 EV 48.0 22.0 35.0 27.1 31.0 31.0 35.4 42.0 6.0 23.0 45.2 26.0 38.1 31.0 23.0 48.0 17.9 8.3 15.9 4.6 11 14.3 F 782.0 1C T5 T11 EV 43.0 15.0 16.0 62.8 5.0 5.0 88.4 33.0 14.0 57.6 8.0 75.8 25.0 55.0 4.0 6.0 5.0 0.5 12 14.6 F 497.0 1C T5 T11 EV + 1 58.0 38.0 22.0 62.1 17.0 17.0 70.7 53.0 16.0 27.0 49.1 30.0 43.4 43.0 68.0 63.0 1.0 9.7 −11.5 2.4 13 13.4 F 981.0 1C t5 t11 EV 58.0 22.0 51.0 12.1 50.0 50.0 13.8 44.0 15.0 31.0 29.5 33.0 25.0 36.0 33.0 −16.1 25.6 −15.2 3.6 14 12.1 F 1470.0 1C T6 T12 EV 42.0 21.0 30.0 28.6 20.0 26.0 38.1 T9–10 6.0 32.0 20.0 25.0 21.9 35.0 −9.4 26.0 28.0 47.0 −16.5 8.3 −30.9 7.6 15 12.3 F 1246.0 1C T5 T10 EV 53.0 23.0 35.0 34.0 32.0 37.3 29.6 T7–8 5.3 48.0 14.0 44.5 7.3 42.0 12.5 18.0 13.0 16.0 0.4 16 14.6 F 982.0 1C T5 T11 EV 53.0 20.0 30.0 43.4 25.0 25.0 52.8 36.0 19.0 27.0 25.0 24.0 33.3 36.0 30.0 27.0 3.8 17 12.6 F 1422.0 1C T5 T11 EV 40.0 16.0 31.0 22.5 17.0 17.0 57.5 31.0 16.0 23.0 25.8 17.0 45.2 24.0 15.0 47.0 20.4 12.0 19.0 2.0 18 14.4 F 1106.0 1C T6 T12 EV 43.0 12.0 17.0 60.5 10.0 21.0 51.2 t10–11 11.0 38.0 9.0 14.0 63.2 20.0 47.4 4.0 4.0 57.0 27.3 7.6 11.4 0.1 19 13.3 F 827.0 1C T4 T11 EV 42.0 24.0 27.0 35.7 18.0 18.0 57.1 38.0 14.0 31.0 18.4 27.0 28.9 21.0 65.0 23.6 18.3 28.8 1.1 Ave 13.6 1079.9 50.3 25.4 29.9 40.8 21.8 28.5 44.4 11.6 40.1 15.9 25.6 36.1 27.7 31.5 30.7 31.3 48.6 1.6 14.8 1.7 2.5 Bold values: Underwent revision to fusion T thoracic, TL thoracolumbar/lumbar, Flex flexibility, EV end vertebra Fig. 2 A, B 14 yo Risser 0 female on the left with a 58° thoracic and 35° thoracolumbar Lenke 1AR curve PA and lateral preoperative radiographs, C first erect PA 22° thoracic and a 24° thoracic and D, E PA and lateral radiographs showing a 21° thoracolumbar at > 3 years follow-up. F, G another 14yo Risser 0 female with a 52° thoracic and 29° thoracolumbar Lenke 1AR preoperative PA and lateral radiographs, H first erect PA radiograph 41° thoracic and I, J PA and lateral radiographs showing 57° thoracic and 33° thoracolumbar at > 3 years follow-up Finally, there was no difference in the rate of revision surgery, with one patient in each group treated with fusion surgery (p = 0.546). Discussion This is the first study to look at outcomes of AVBT based on curve type. In this study, we found an equivalent correction of the thoracic curves in both lenke 1A and 1C curves, but less correction of the uninstrumented thoracolumbar/lumbar curves in the Lenke 1C patients. With an average correction of only 25% in the uninstrumented Lenke 1C thoracolumbar/lumbar curves it would be easy to suggest that these patients are not good candidates for AVBT, but there was considerable overlap in these results with curve correction ranging from − 9 to 76%. Additionally, much like the reported results for selective fusion in 1C curves, we found that the correction of the uninstrumented thoracolumbar/lumbar curve correlated with the correction of the instrumented thoracic curve [7]. This would suggest that for ABVT, maximal correction of the instrumented thoracic curve will result in maximal correction of the thoracolumbar/lumbar curve as well. The challenge is that unlike a fusion where the correction of the instrumented curve is fixed, AVBT can result in increasing correction or overcorrection with continued growth. In this study, we showed that the instrumented and uninstrumented curves corrected an additional 3–7% after their first erect radiograph depending on the curve location and type, with wide variation from − 66 to 118%. Given the additional correction these patients may undergo, the concerns for overcorrection and under correction shown in Shin et al. and Newton et al.’s studies [12, 16] appear validated. Interestingly, despite the variable correction rates, both curve types in our study had similar rates of revision surgery and no patients who underwent revision surgery due to overcorrection. We did have one patient in each group undergo revision surgery and in both cases showed initial correction of 39% for the Lenke 1A patient and 12% for the Lenke 1C patient and neither patient growth modulated. We suspect that these numbers will increase with increased follow-up as more recent studies on AVBT have suggested increased revision rates with longer-term follow-up. Particularly because we noted that 50% of all patients had an apparent tether rupture with an average loss of correction of 5° though this had a large range from − 2 to 34°, and thus this number will potentially increase with time. This is also the first study to look at the coronal alignment outcomes in patients after AVBT. The concept of the Cone of Economy (COE) has been used to define balance, with unbalanced curves or those deviating > 1.5–4 cm from the CSVL experiencing an increased risk of trunk shift, adding on, pain and increased energy expenditure [17–19]. In addition to the correction of both the instrumented and uninstumented curves to less than 35° we found that 77% of patients in each group showed coronal deviation less than 2 cm of the CSVL, for both C7 and the apical vertebra. Rates of adding on after selective thoracic fusion varies from 6 to 21% in the literature, with increased rates seen in patients with 1AR subtypes that were hypokyphotic [20, 21]. We anticipate that future studies will include an analysis of these subtypes in the results of selective AVBT. Due to the retrospective registry nature of this study there are several limitations. Including the fact that there was a large number of patients with incomplete data and due to the Covid-19 pandemic we were unable to obtain that additional data. Leading to the exclusion of 44% of patients that could be potentially included in this study. We also acknowledge that some surgeons would elect to tether the thoracolumbar curve in Lenke 1c curves, but as our goal was to study the response of the uninstrumented curve we elected to not include those patients. Furthermore, as much of the data was collected prior to the routine use of SMS, Risser stage was also included in the analysis. Additionally, we did not have complete patient height data, nor were all the images calibrated, so we were unable to evaluate changes in height clinically or radiographically. We were also not powered to detect a difference in the rates of correction or adding on based on LIV. Finally, as we relied on a change of more than 5° between adjacent levels to assess for probable tether rupture, and it is possible we are underestimating the true incidence of rupture in these patients. At present, AVBT has a high rate of revision surgery compared to selective thoracic fusion and remains in the experimental stage both from a technical and patient selection standpoint. As we elucidate the appropriate indications and intraoperative techniques for AVBT we will be able to better predict the outcomes for skeletally immature patients with thoracic and thoracolumbar/lumbar scoliosis. Meanwhile, judicious patient selection, extensive patient counseling and vigorous outcomes analysis are essential for its application. Author contributions MCW, LB: conception/design, data acquisition, analysis, interpretation, drafted/revised work, approved the final version. CH: conception/design, data acquisition, analysis, approved the final version. FM, SP: conception/design, data acquisition, drafted/revised work, approved the final version. RH: conception/design, data acquisition, interpretation, drafted/revised work, approved the final version. All authors agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Funding POSNA Research Startup Grant; Shriners Hospital for Children Directed Research Grant. Data availability All data is available in Table 4. Declarations Conflict of interest Dr. Welborn reports grants from POSNA, grants from Shriners Hospital for Children, during the conduct of the study; personal fees and other from Depuy Synthes, personal fees from Nuvasive, personal fees from Stryker/K2M, personal fees from and Zimmer/Biomet outside the submitted work. Dr. Blakemore reports personal fees from Stryker Spine, other from Pediatric Spine Foundation, other from Spine Deformity Journal, outside the submitted work. In addition, Dr. Blakemore has a patent U.S. Patent Application 10,548,639 pending to Stryker Spine, and a patent.US Patent Application 17/091773 pending to Stryker Spine. Dr. Handford has nothing to disclose. Dr. Miyanji reports personal fees from Depuy Synthes, personal fees from Stryker, personal fees and other from ZimVie, personal fees from Orthopaediatrics, grants from Setting Scoliosis Straight Foundation, other from AO Fracture, other from AO tumour, other from AO Deformity, outside the submitted work. Dr. Parent reports personal fees from EOS-imaging, personal fees from Spinologics, personal fees from K2M, personal fees from EOS-imaging, personal fees from DePuy Synthes Spine, other from Academic Research chair in spine deformities of the CHU Sainte-Justine (DePuy), grants from DePuy Synthes Spine, grants from Canadian Institutes of Health Research, grants from Pediatric Orthopaedic Society of North America, grants from Scoliosis Research Society, grants from EOS imaging, grants from Canadian Foundation for Innovation, grants from Setting Scoliosis Straight Foundation, grants from Natural Sciences and Engineering Council of Canada, grants from Fonds de recherche Québec—Santé, grants and other from Orthopaedic Research and Education Foundation, other from DePuy Synthes, other from Medtronic, other from Orthopaediatrics, outside the submitted work. Dr. El-Hawary reports grants and personal fees from Medtronic Canada, grants and personal fees from Depuy Synthes Spine, personal fees and other from Orthopediatrics, outside the submitted work. Ethical approval (IRB) This is a Western IRB approved study #20160128. Research involving human participants and/or animals “All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee (include name of committee + reference number) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.” Informed consent Informed consent was obtained from all patients and their parents. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Lenke LG Betz RR Clements D Curve prevalence of a new classification of operative adolescent idiopathic scoliosis: does classification correlate with treatment? Spine 2002 27 6 604 611 10.1097/00007632-200203150-00008 11884908 2. Chan CYW Aziz I Chai FW A silver medal winner at the 13th world Wu Shu Championship 2015 17 months after selective thoracic fusion for adolescent idiopathic scoliosis: a case report Spine 2017 42 4 E248 e252 10.1097/brs.0000000000001748 28207671 3. Thompson JP Transfeldt EE Bradford DS Decompensation after Cotrel–Dubousset instrumentation of idiopathic scoliosis Spine 1990 15 9 927 931 10.1097/00007632-199009000-00017 2259983 4. Lonner BS Ren Y Upasani VV Disc degeneration in unfused caudal motion segments ten years following surgery for adolescent idiopathic scoliosis Spine Deform 2018 6 6 684 690 10.1016/j.jspd.2018.03.013 30348344 5. Lenke LG Edwards CC 2nd Bridwell KH The Lenke classification of adolescent idiopathic scoliosis: how it organizes curve patterns as a template to perform selective fusions of the spine Spine 2003 28 20 S199 207 10.1097/01.brs.0000092216.16155.33 14560193 6. Newton PO Faro FD Lenke LG Factors involved in the decision to perform a selective versus nonselective fusion of Lenke 1B and 1C (King-Moe II) curves in adolescent idiopathic scoliosis Spine 2003 28 20 S217 223 10.1097/01.brs.0000092461.11181.cd 14560195 7. Ilgenfritz RM Yaszay B Bastrom TP Lenke 1C and 5C spinal deformities fused selectively: 5-year outcomes of the uninstrumented compensatory curves Spine 2013 38 8 650 658 10.1097/BRS.0b013e3182793092 23089928 8. Buyuk AF Milbrandt TA Mathew SE Measurable thoracic motion remains at 1 year following anterior vertebral body tethering, with sagittal motion greater than coronal motion J Bone Jt Surg Am 2021 10.2106/jbjs.20.01533 9. Newton PO Bartley CE Bastrom TP Anterior spinal growth modulation in skeletally immature patients with idiopathic scoliosis: a comparison with posterior spinal fusion at 2 to 5 years postoperatively J Bone Jt Surg Am 2020 102 9 769 777 10.2106/jbjs.19.01176 10. Samdani AF Ames RJ Kimball JS Anterior vertebral body tethering for immature adolescent idiopathic scoliosis: one-year results on the first 32 patients Eur Spine J 2015 24 7 1533 1539 10.1007/s00586-014-3706-z 25510515 11. Samdani AF Pahys JM Ames RJ Prospective follow-up report on anterior vertebral body tethering for idiopathic scoliosis: interim results from an FDA IDE study J Bone Jt Surg Am 2021 10.2106/jbjs.20.01503 12. Shin M Arguelles GR Cahill PJ Complications, reoperations, and mid-term outcomes following anterior vertebral body tethering versus posterior spinal fusion: a meta-analysis JB JS Open Access 2021 10.2106/jbjs.oa.21.00002 34179678 13. Baroncini A Trobisch PD Migliorini F Learning curve for vertebral body tethering: analysis on 90 consecutive patients Spine Deform 2021 9 1 141 147 10.1007/s43390-020-00191-5 32827085 14. Mathew S Larson AN Potter DD Defining the learning curve in CT-guided navigated thoracoscopic vertebral body tethering Spine Deform 2021 10.1007/s43390-021-00364-w 34264474 15. Alanay A Yucekul A Abul K Thoracoscopic vertebral body tethering for adolescent idiopathic scoliosis: follow-up curve behavior according to sanders skeletal maturity staging Spine 2020 45 22 E1483 e1492 10.1097/brs.0000000000003643 32756290 16. Newton PO Kluck DG Saito W Anterior spinal growth tethering for skeletally immature patients with scoliosis: a retrospective look two to four years postoperatively J Bone Jt Surg Am 2018 100 19 1691 1697 10.2106/JBJS.18.00287 17. Schwab F Patel A Ungar B Adult spinal deformity—postoperative standing imbalance: how much can you tolerate? An overview of key parameters in assessing alignment and planning corrective surgery Spine 2010 35 25 2224 2231 10.1097/BRS.0b013e3181ee6bd4 21102297 18. Dubousset J Weinstein SL Three-dimensional analysis of the scoliotic deformity Pediatric spine: principles and practice 1994 New York Raven Press 479 496 19. Glassman SD Berven S Bridwell K Correlation of radiographic parameters and clinical symptoms in adult scoliosis Spine 2005 30 6 682 688 10.1097/01.brs.0000155425.04536.f7 15770185 20. Cho RH Yaszay B Bartley CE Which Lenke 1A curves are at the greatest risk for adding-on… and why? Spine 2012 37 16 1384 1390 10.1097/BRS.0b013e31824bac7a 22322370 21. Tan JH Hey HWD Wong G Lumbar adding-on of the thoracic spine after selective fusion in adolescent idiopathic scoliosis Lenke types 1 and 2 patients: a critical appraisal Spine 2021 46 3 E167 e173 10.1097/brs.0000000000003806 33181768
PMC009xxxxxx/PMC9997729.txt	==== Front Vaccine Vaccine Vaccine 0264-410X 1873-2518 Elsevier Ltd. S0264-410X(23)00251-7 10.1016/j.vaccine.2023.03.004 Letter to the Editor Lessons from the Bolivian vaccine mandate Rivas Diana Reyna Zeballos Institute of Collective Health, Federal University of Bahia, Salvador, Brazil Public Health Department, Higher University of San Andres, La Paz, Bolivia Ticona Juan P. Aguilar ⁎ Institute of Collective Health, Federal University of Bahia, Salvador, Brazil Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, Brazil Public Health Department, Higher University of San Andres, La Paz, Bolivia Doss-Gollin Simon University of Maryland School of Medicine, Baltimore, MD, USA ⁎ Corresponding author at: Universidade Federal da Bahia, R. Basílio da Gama, 316 - Canela, Salvador, 40110-040 Bahia, Brazil. 9 3 2023 19 6 2023 9 3 2023 41 27 39513953 10 6 2022 18 2 2023 2 3 2023 © 2023 Elsevier Ltd. All rights reserved. 2023 Elsevier Ltd Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcDear editor Vaccination is the most important strategy for prevention of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection, responsible for the ongoing coronavirus 2019 (COVID-19) pandemic [1], [2]. Public support for the use of vaccines to protect against infectious diseases including COVID-19 has decreased over the years, as antivaccine movements have grown up across the world [3]. The COVID-19 pandemic has starkly demonstrated the way in which structural problems such as poverty and inequity limit the ability of governments to take action to control the spread of the virus, particularly in less wealthy countries such as Bolivia, a lower-middle-income country located in central South America [4], [5]. Despite availability of the vaccines, the vaccination rate in Bolivia has been among the lowest in the region, and as of December 21st, 2021, only 46% of the population had received at least one dose of the vaccine [6]. Furthermore, as of that time, the number of vaccinations per day had decreased steadily since August 2021, likely as a result of decreased risk perception around infection during the lull in COVID-19 cases reported between the Delta and Omicron waves in the country (Fig. 1 ).Fig 1 A) 7-day rolling average of persons that received the first dose of COVID-19 vaccine B) 7-day rolling average of persons fully vaccinated against COVID-19 C) 7-day moving average of daily new case of COVID-19 cases in Bolivia over the same period since vaccination began. The dashed blue line marks the enaction of the vaccine mandate in Bolivia (Supreme Decrees 4640 and 4641), the first dashed red line marks the delay of the policy application and the second marks the lifting of the mandate. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.) On December 22nd, 2021, the Bolivian government enacted Supreme Decrees 4640 and 4641, with the aim of increasing vaccination rates by implementing a national COVID-19 mandate, which would require individuals to carry official proof of vaccination in order to access public and governmental spaces beginning January 1st, 2022 [7], [8]. A series of conflicts, however, resulted in first the delay of its implementation to January 5th, and subsequently its abrogation on January 19th, 2022, only 28 days after the bill was enacted [8], [9], [10]. During those 28 days, the governmental mandate was moderately successful at increasing the number of vaccinations per day, particularly among the unvaccinated (Fig. 1). In this short period, Bolivia’s COVID-19 vaccination coverage increased by 9.6% for first doses and by 4.4% for second doses. Challenges with the legislation’s implementation, were eventually responsible for the policy demise. Most critically, the short time between the mandate’s announcement and its implementation resulted in insufficient time for planning vaccine rollout and managing supply shortages. This lack of planning placed a heavy burden on a health system that was still recovering from the initial strain placed on it by previous stages of the COVID-19 pandemic including institutional budget deficits, and the burnout of health professionals who had been exposed to challenging and dangerous work without sufficient support [11]. New vaccination centers were not created, and existing centers were overcrowded and often had to share their physical spaces with testing centers [9], [10]. As a result, the long queues and wait times for vaccination increased public dissatisfaction with the policy [12]. This was then capitalized on by the anti-vaccine movement, which had hitherto been scattered and disorganized in Bolivia, but was brought together by evangelical Christian leaders and the rampant spread of misinformation [9], [13], [14]. Estimation of the legislation’s impact is further complicated by the arrival of the omicron variant, which was confirmed in Bolivia in early January 2022. During this time the number of new cases rose higher than in previous COVID-19 waves [15]. Critically, however, in the time since the lifting of the vaccine mandate, there has been a significant decrease in the rate of distribution of first doses of the vaccine despite the number of COVID-19 cases and deaths associated with omicron remaining high (Fig. 1). Mandatory vaccination has a longstanding precedent in certain contexts within Bolivia, such as public schools, where a complete vaccination card is required for enrollment of new students. In addition to mandates, successful government incentive programs have also been offered, such as one providing Conditional Cash Transfers to children and their mothers who received vaccines. A study that evaluated the COVID-19 vaccine prior to its implementation found that 84.1% of the population agree to get vaccinated [5] the low adherence to vaccination despite high acceptance implies that social and political factors continue to impact populations' decisions, in addition with misinformation. Moreover, it is fundamental to implement long-term monitoring of COVID-19 vaccine acceptance to identify vulnerable populations and focus campaigns to promote vaccination. Finally, the recent rise of anti-vaccine groups, demonstrates the need to improve public communication about vaccine safety as well as to develop better tools and policies to combat the spread of misinformation. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Data availability This study use secondary data available in the reference ==== Refs References 1 Le T.T. Cramer J.P. Chen R. Mayhew S. Evolution of the COVID-19 vaccine development landscape Nat Rev Drug Discov 19 2020 667 668 32887942 2 Nery N, Jr., Ticona JPA, Cardoso CW, Prates APPB, Vieira HCA, Salvador de Almeida A, et al. COVID-19 vaccine hesitancy and associated factors according to sex: A population-based survey in Salvador, Brazil. PLOS One. 2022;17:e0262649. 3 McClure C.C. Cataldi J.R. O’Leary S.T. Vaccine Hesitancy: Where We Are and Where We Are Going Clin Ther 39 2017 1550 1562 28774498 4 Hummel C. Knaul F.M. Touchton M. Guachalla V.X.V. Nelson-Nuñez J. Boulding C. Poverty, precarious work, and the COVID-19 pandemic: lessons from Bolivia Lancet Glob Health 9 2021 e579-e81 5 Zeballos Rivas D.R. Lopez Jaldin M.L. Nina Canaviri B. Portugal Escalante L.F. Alanes Fernández A.M.C. Aguilar Ticona J.P. Social media exposure, risk perception, preventive behaviors and attitudes during the COVID-19 epidemic in La Paz, Bolivia: A cross sectional study PLoS One 16 2021 e0245859 33481945 6 Roser M, Ritchie H, Ortiz-Ospina E, Hasell J. Coronavirus pandemic (COVID-19). Our world in data. 2020. 7 Gaceta Oficial del Estado Plurinacional de Bolivia. [cited 22 Feb 2022]. Available: http://www.gacetaoficialdebolivia.gob.bo/normas/listadonor/11. 8 Analytica O. Bolivia COVID-19 card scheme could boost vaccination. Emerald Expert Briefings. 9 Graham T. the Guardian [Internet]. Misinformation and distrust: behind Bolivia’s low Covid vaccination rates; 6 fev 2022 [citado 1 maio 2022]. Disponível em: https://www.theguardian.com/global-development/2022/feb/06/misinformation-and-distrust-behind-bolivias-low-covid-vaccination-rates. 10 Osborn C. Foreign Policy [Internet]. Omicron Spells the Return of Pandemic Political Calculus; 7 jan 2022 [citado 1 maio 2022]. Disponível em: https://foreignpolicy.com/2022/01/07/omicron-covid-pandemic-latin-america-testing-case-data/. 11 Humire JM. Bolivia y COVID-19: Una historia de dos pandemias. Revista UNISCI. 2021. 12 Amid Bolivia's Covid surge, long queues for vaccines in short supply - La Prensa Latina Media; [citado 1 maio 2022]. Disponível em: https://www.laprensalatina.com/amid-bolivias-covid-surge-long-queues-for-vaccines-in-short-supply/. 13 Bolivian Thoughts in an Emerging World [Internet]. Bolivia yielded to pressure from anti-vaccine groups and suspended the requirement for a health pass in public places; [citado 1 maio 2022]. Disponível em: https://bolivianthoughts.com/2022/01/21/bolivia-yielded-to-pressure-from-anti-vaccine-groups-and-suspended-the-requirement-for-a-health-pass-in-public-places/. 14 Reuters [Internet]. 'Vaccines are satanic': Bolivia battles fake news in inoculation drive; 20 maio 2021 [citado 1 maio 2022]. Disponível em: https://www.reuters.com/world/americas/vaccines-are-satanic-bolivia-battles-fake-news-inoculation-drive-2021-05-20/. 15 Dong E. Du H. Gardner L. An interactive web-based dashboard to track COVID-19 in real time Lancet Infect Dis 20 2020 533 534 32087114
PMC009xxxxxx/PMC9998140.txt	==== Front Curr Nutr Rep Curr Nutr Rep Current Nutrition Reports 2161-3311 Springer US New York 36894741 465 10.1007/s13668-023-00465-0 Review COVID-19, the Gut, and Nutritional Implications Bell Matthew G. 1 http://orcid.org/0000-0002-6877-1712 Ganesh Ravindra [email protected] 2 Bonnes Sara L. 2 1 grid.66875.3a 0000 0004 0459 167X Department of Internal Medicine, Mayo Clinic, 200 1st Street SW, Rochester, MN 55905 USA 2 grid.66875.3a 0000 0004 0459 167X Division of General Internal Medicine, Mayo Clinic, 200 1st Street SW, Rochester, MN USA 10 3 2023 2023 12 2 263269 7 2 2023 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Purpose of Review Our goal is to provide the most recent and accurate scientific evidence available regarding COVID-19’s interaction with the human gut and the role of nutrition/nutritional supplementation in the prevention and treatment of the disease. Recent Findings Gastrointestinal symptoms of COVID-19 are common and often persist even after classically defined illness resolution. Nutritional status and content have been shown to impact infection risk and severity. Well-balanced diets are associated with decreased infection risk/severity, and early nutrition is associated with better outcomes in the critically ill. No specific vitamin supplementation regimen has shown consistent benefit for infection treatment or prevention. Summary The impact of COVID-19 extends far past the pulmonary system, and its impact on the gut should not be ignored. For those interested in adopting lifestyle modifications to prevent severe COVID-19 infection/side effects, consideration should be made for adoption of a well-balanced diet (e.g., Mediterranean style), utilization of probiotics, and addressing nutritional/vitamin deficiencies. Future, high-quality research is needed in this arena. Keywords SARS-CoV-2 COVID-19 Nutrition Microbiome issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction COVID-19, a disease caused by the novel coronavirus (SARS-CoV-2), has drastically changed the landscape of day-to-day life and, particularly, the healthcare field. The virus rapidly spread across the global landscape with the first cases being reported in December of 2019 and an official pandemic declaration by the World Health Organization (WHO) occurring only a few months later in March 2020 [1, 2]. Since then, the WHO reports an estimated 600 million infections globally with nearly 6.5 million deaths [1], The public health repercussions including lockdowns, border closures, and mask and vaccine mandates created significant social and economic impact on citizens around the world. Given the impact of the COVID-19 pandemic, efforts to better understand this novel pathogen, slow/stop its transmission, and improve the outcomes of those already infected surged, leading to an inundation of scientific information, societal recommendations, and purported remedies with varying degrees of accuracy. As the pandemic evolved, clear risk factors for COVID-19 progression were described including increased severity in patients with obesity and/or diabetes [3, 4]. In addition, while traditionally a respiratory pathogen, COVID-19 was found to be associated with significant gastrointestinal (GI) symptoms including diarrhea, abdominal pain, and anorexia [5–7]. With this described connection with metabolic comorbidities and GI symptoms, a particular area of interest and controversy that emerged was that of COVID-19’s interaction with the gut and the role of nutrition (and nutritional supplementation) in the prevention and treatment of the disease. Our goal is to provide the most recent and accurate scientific evidence available regarding COVID-19’s interaction with the human gut and the role of nutrition/nutritional supplementation in the prevention and treatment of the disease. COVID-19 Pathogenesis SARS-CoV-2 is a single-stranded RNA virus that is transmitted through aerosols and droplets. The virus is made up of a framework of proteins: envelope, membrane, nucleocapsid, and spike proteins [8]. Each protein in this framework serves a specific function in the pathogenesis of SARS-CoV-2. Specifically, the spike protein mediates the binding of SARS-CoV-2 to the ACE2 receptor of the host cells. Binding of the spike protein to the ACE2 receptor of host cells is what ultimately leads to membrane fusion and infection/viral replication [9]. Subsequently, this infection of host respiratory epithelial cells leads to local inflammation and, ultimately, the classic symptoms of COVID-19 which include cough, rhinorrhea, and fever. However, SARS-CoV-2 can also infect cells outside of the respiratory tract. In fact, the ACE2 receptor is expressed extensively throughout the body in tissues such as the small intestine, vascular endothelium, kidneys, heart, and the central nervous system [10, 11]. Systemic infection and subsequent inflammation is what leads to more severe cases of COVID-19 which are driven by “cytokine storm,” membrane permeability, sepsis, and acute respiratory distress. The presence of ACE2 receptors outside the respiratory tract will also become important when later considering GI symptoms of COVID-19 as well as discussing the management of post-COVID-19 complications. Nutrition and Viral Infections/Immune System Interest in the connection between diet, nutrition, and micronutrient/trace element supplementation preceded the COVID-19 pandemic. Adequate nutrition and dietary components are known to be critical to the healthy function of the immune system. For example, it is well established that protein poor diets are associated with a higher risk of infection. In this same way, multiple vitamins (vitamin A, vitamin D, vitamin C, vitamin E, etc.) and trace elements (zinc, selenium, iron, etc.) are known to serve as critical co-factors in immune-related enzymatic function [12]. In addition to their direct impact on immune function and infection prevention, many of these components are also postulated to have concurrent anti-inflammatory and anti-oxidative properties that could impact the treatment of COVID-19. Further, a healthy gut helps to mount and maintain a robust immunological response which helps contain the SARS-CoV-2 virus in the upper airway and may assist in the prevention of invasion of the lung parenchyma and progression of COVID-19 [13]. Gastrointestinal manifestations of COVID-19 are associated with gut dysbiosis which is associated with immune dysregulation and delayed clearance of SARS-CoV-2. Similar patterns of gut dysbiosis have been associated with increased mortality in other respiratory infections and thus present probiotics as an attractive therapeutic option [13]. As mentioned earlier, severe COVID-19 is marked by widespread, systemic inflammatory reaction. Thus, both dietary components (vitamins, minerals, trace elements, etc.) and complete dietary patterns (Mediterranean, ketogenic, plant-based, etc.) that are associated with anti-inflammatory effect have also been postulated to assist in the prevention and treatment of severe COVID-19. We explore each of these subjects in detail throughout this review. COVID-19 and the Gut While classically a respiratory illness, COVID-19 can have a dramatic impact on the gut. In fact, a meta-analysis of over 18,000 patients worldwide displayed that nearly one-third of all COVID-19 sufferers experienced GI symptoms. Of all GI symptoms, diarrhea (11.5%), nausea and vomiting (6.3%), and abdominal pain (2.3%) were the most commonly reported [6]. The rate of GI symptoms rises to nearly 75% when solely considering critically ill patients, specifically, with the most common manifestations being elevated transaminases (67.3%), intolerance of feeding (46.2%), and ileus (55.8%) [7]. In fact, a recent meta-analysis demonstrated that gastrointestinal symptoms are associated with an increased risk of severe COVID-19 with an odds ratio of 2.8 [14]. This association of gastrointestinal symptoms with severe COVID-19 did not translate into increased mortality per another recent meta-analysis [15]. Gastrointestinal symptoms were also found to persist beyond the resolution of acute COVID-19 symptoms with 16% of patients reporting persistent GI symptoms (abdominal pain, diarrhea, and constipation) even 100 days after classically defined recovery [16]. While some of these symptoms could be attributed to general illness, it is believed that COVID-19 directly accounts for at least a portion of the described gastrointestinal toxicity. This is supported by a matched comparison study in which COVID-19 sufferers displayed nearly double the rate of gastrointestinal manifestations when compared with equally ill patients who were not COVID-19 positive [17]. There are two major theories to explain the prevalence of GI symptoms in COVID-19 sufferers. The first postulate, which we have already discussed, is that SARS-CoV-2 virus infects enterocytes via the ACE2 receptor which is known to be expressed in the GI tract. Direct infection and inflammation of the gastrointestinal lining could explain many of the GI manifestations of the virus and would also account for why these symptoms appear early in the disease course [18, 19]. This theory may explain why GI symptoms persist as well, as studies have reported cases of SARS-CoV-2 antigen detection in enteric biopsies up to 3 months after COVID-19 infection [20]. The second theory is that COVID-19 infection disrupts the gut microbiome, leading to the described symptoms. Multiple studies have displayed distortion of the microbiome in the setting of COVID-19 infection, and some have postulated that this alone could account for the acute gastrointestinal symptoms as well as the persistent symptoms seen in those with longstanding COVID-19 complications. COVID-19 and the Microbiome The human gut is the largest immunological organ system in the body, and the microbiome that the gut houses plays a pivotal role in immune response [21]. Significant effort has been made to further understand the role that the gut microbiome is playing in COVID-19 disease progression and recovery. Microbiome surveys of COVID-19 sufferers versus healthy individuals as well as severe COVID-19 versus milder cases have displayed a change in both microbiome diversity and have identified specific organisms that may be associated with severity [22–24]. Specific genera of bacteria such as Streptococcus, Prevotella, and Rothia (traditionally opportunistic and inflammatory organisms) were found more abundantly in the feces of COVID-19 patients, whereas Faecalibacterium (considered an anti-inflammatory organism) was found more abundantly in the feces of healthy controls [24, 25••, 26]. Overall, there appears to be significant evidence for decreased microbiome diversity, depletion of favorable commensals, and an increase in opportunistic GI pathogens in the setting of COVID-19 infection [25••]. These compositional changes in the GI microbiome have been directly associated with increased inflammation with COVID-19 infection—elevated cytokine levels, C-reactive protein, transaminases, and lactate dehydrogenase—which further supports the immunologic role of the gut [27•]. Probiotics With the described alternations of the gut microbiome in the setting of COVID-19, probiotics have been considered as a potential intervention for both disease treatment and prevention. The results of current studies have been variable, but there does appear to be some benefit to probiotic use in the setting of COVID-19 infection and exposure. Specifically, a retrospective cohort study displayed significant reduction in hospitalization length, time to clinical improvement, and time to COVID-19 negativity in those who received a probiotic [28]. Multiple studies have also shown a shortened duration of diarrhea in those who are treated with probiotic after testing positive for COVID-19 [29, 30]. Probiotics are well-tolerated medications without significant side effects or adverse reaction profiles. For this reason, there appears to be an argument for probiotic use in the setting of COVID-19 infection. However, probiotic use in the setting of COVID-19 prevention remains under investigation with several pending clinical trials directed at this question specifically. Fecal Microbiota Transplant In a similar fashion to probiotics, fecal microbiota transplantation (FMT) has been considered as a treatment option for COVID-19-related gut dysbiosis. FMT is most commonly used to treat recurrent or severe Clostridioides difficile infections; however, its benefits have also been seen in other instances of dysbiosis. So far, only a few small studies/case studies of FMT in COVID and post-COVID patients have been undertaken and do show some promise [31, 32]. Future clinical studies will be needed to further investigate the safety and efficacy of COVID-19 treatment with FMT versus other less invasive alternatives such as probiotic treatment [33]. Diet Styles It is well established that nutritional status plays an important role in immune function and that specific metabolic conditions (e.g., obesity and diabetes) are associated with an increased risk of severe COVID-19 sequela. It is reasonable to consider the role that daily dietary composition plays in the risk of COVID-19 infection and severity. We will review the most common implicated dietary patterns and the rationale behind their proposed protective or deleterious impact on COVID-19 immune response. Healthy Plant-Based Diet There is not a single, accepted definition or criteria for a “healthy plant-based diet” Ranging from the exclusion of all animal products to simple optimization of plant-based ingredients and high-quality whole foods, the plant-based spectrum is quite wide. For this purpose, and in the most pertinent literature, vegan, vegetarian, and more general plant-based patterns are all included. As a whole, plant-based diets have been associated with prevention and treatment of type 2 diabetes, coronary artery disease, and hypertension [34, 35]. A recent study, comprised mostly of healthcare workers, suggested that those following a plant-based diet had a 73% lower odds ratio of moderate-to-severe COVID-19. This same study also reported that individuals following a plant-based diet had a lower odds ratio of COVID-19 infection (defined as a positive PCR or antibody test) [36]. While there is certainly risk for confounding, particularly with other healthy behaviors likely practiced by this population, this study does provide signal to support the impact of diet on viral infection and severity. Ketogenic Diet The ketogenic diet (KD) is a dietary pattern that is characterized by reduced consumption of carbohydrates while relying heavily on dietary fats for energy. This dietary pattern is aimed at the development of metabolic ketosis. The proposed role of KD in the prevention and treatment of COVID-19 is twofold with the first mechanism being secondary to its weight loss benefits. As previously discussed, obesity is a major risk factor for COVID-19 and disease severity. The ketogenic diet has been touted as a successful diet for weight loss and, therefore, may reduce COVID-19 risk and severity. KDs have also been supported for their potential anti-inflammatory impact [37]. Specifically, KD could reduce airway lipid droplet formation and subsequent inflammation as well as dampening inflammasome response to reducing systemic complications [38, 39]. However, clinical trial data to support these propositions are lacking. In fact, there may be data favoring other dietary patterns over KD including, but not limited to, a purely plant-based diet [36]. Mediterranean Diet The Mediterranean diet is rich in whole grains, legumes, vegetables, fruits, nuts, and other whole foods. This diet includes olive oil as the primary fat additive and seafood/fish as the primary protein. Overall, this is quite like a pescatarian diet, but dairy and poultry are also included, however, in moderation. Similar to the previously discussed dietary patterns, the Mediterranean diet has been associated with positive outcomes such as weight loss, cardiovascular health, and diabetes prevention/treatment [40]. The Mediterranean diet has also been associated with decreased inflammatory markers [41] as well as reduction in the risk of respiratory infections [42]. In regard to COVID-19 specifically, it appears that individuals who are adherent to the Mediterranean diet have a lower risk of COVID-19 infection [43, 44]. The Mediterranean diet is also the most common recommended diet for those suffering with extended, long-COVID-19 symptoms. Overall, no single dietary pattern has been found to be superior to the rest when it comes to COVID-19 prevention or treatment. However, there does seem to be a benefit to balanced diets that are high in whole-food content and lower in processed ingredients. There is no need for extreme dietary changes, but focusing on a balanced intake that avoids processed and high-fat foods appears to bring health benefits both inside and outside the realm of COVID-19. Nutritional Support in Critically Ill COVID-19 Severe COVID-19 is marked by progressive respiratory failure, ARDS, and necessitation of mechanical ventilation. These patients often have prolonged hospitalizations and intensive care unit stays. Management of nutrition in these critically ill patients is paramount to the acute treatment and long-term recovery from COVID-19. Most of these critically ill patients require enteral nutrition (EN) to meet their energy requirements. EN in COVID-19 patients has posed several challenges. Early in the pandemic, there was a reported trend of avoiding EN to reduce nursing burden and provider infection exposure as EN required a higher bedside presence [45]. However, studies have since shown the EN is overall well tolerated and does not pose an increased risk to those involved [46]. EN is preferred over parenteral nutrition (PN) as it is more physiologic and decreases risk of gut dysfunction [47]. A recent systematic review and meta-analysis of critically ill patients found a preference for early adoption of enteral feeding in COVID-19 patients. This study utilized the American Society of Parenteral and Enteral Nutrition definition for early enteral nutrition as feeding that is commenced within 24 to 36 h of ICU admission or 12 h of mechanical ventilation. Early nutrition was found to significantly reduce the risk of mortality with a relative risk reduction of 11%. However, when comparing early EN and late enteral EN or PN, there was no significant difference in the length of stay or length of ventilation [48•]. Overall, in the treatment of critically ill patients with COVID-19, we support the early adoption of EN if it can be tolerated. Vitamin Supplementation Vitamin C Vitamin C, or ascorbic acid, has long been known to have anti-inflammatory benefits and has previously been used in the setting of severe sepsis. Vitamin C became a popular daily supplement early in the COVID-19 pandemic for this same reason. However, as more clinical trials and systematic reviews have become available, the benefit of vitamin C in COVID-19 prevention and treatment remains uncertain and controversial. Depending on the specific endpoint in question, randomized control studies have found evidence to support vitamin C supplementation in critically ill patients [49, 50]. However, these results have been inconsistent, often confounded by adjunctive therapies, and even contradicted by other studies [51–54]. Ultimately, consistent consensus data to support the use of vitamin C supplementation in COVID-19 prevention or treatment, regardless of disease severity, is lacking. Selenium and Zinc It has been noted that patients with lower levels of selenium and zinc are at higher risk of developing COVID-19, and deficiency of these minerals has further been associated with increased severity of COVID-19 [55, 56]. An interesting ecological study from China demonstrated increased severity of COVID-19 infection with selenium deficiency in the topsoil of the region of patient origin [57]. Another study correlated deficiency of selenium and zinc with increased severity of COVID-19 and elevated levels of CRP [58]. While there are described associations between selenium and zinc deficiency and risk of developing COVID-19, there are no clinical trials at this time that support the use of either zinc or selenium supplementation as a treatment for COVID-19. Vitamin D Vitamin D plays multiple modulatory roles in the immune system. In fact, studies have shown an association between low serum 25-hydroxyvitamin D and an increased risk of respiratory tract infections. It was only natural, therefore, that vitamin D supplementation be considered as both prophylaxis and treatment of COVID-19 [59, 60]. A multitude of randomized control trials have attempted to answer these questions, with varied methods and results. Regarding prophylaxis, the results have been mixed. A study with a short-term follow-up (1 month) showed a modest benefit against infection with vitamin D supplementation [61]. However, the largest study to date, performed in the UK, involved over 6000 participants with suboptimal vitamin D levels at baseline and found no benefit to a test-and-treat model for vitamin D deficiency and COVID prophylaxis [62•]. This negative result was further supported by a Scandinavian study of low-dose vitamin D/cod oil supplementation that also displayed negative results [63]. The studies of vitamin D in COVID-19 treatment have showed similar, varied results. A small, open-label study from Spain concluded that vitamin D supplementation significantly reduced the risk of ICU admission [64]. Meanwhile, other randomized control studies have shown benefit in the same clinical setting with similar endpoints. With the inconsistent results in both the treatment and prevention of COVID-19 with vitamin D supplementation, no national or international body currently recommends supplementation in either setting. Future well-designed randomized control studies with caution for confounding variables (risk factors, vaccination study, adjunct therapies, etc.) will be needed to advance the knowledge in this realm. Conclusion The medical impact of COVID-19 extends far past the pulmonary system with significant impact noted on the gastrointestinal system with differences noted with varied nutritional approaches. There was significant interest early in the pandemic about the role of nutritional approaches in the treatment of COVID-19, but the purported impact of these approaches was not realized. For those interested in adopting lifestyle modifications to prevent severe COVID-19 infection/side effects, focus should be placed on the interventions that are supported by evidence-based practice and have been shown to be safe and effective. Unfortunately, despite being 2.5 years into the pandemic, there is still a tremendous need for high-quality research on these topics. Based on our review, we would recommend adoption of a well-balanced nutritional model that is low in processed foods (such as a Mediterranean-style diet), daily exercise directed at cardio-pulmonary health and weight management, and vaccination against COVID-19. For those who become infected, specific focus should remain on maintaining nutritional quality, regardless of disease severity, and a compelling argument can be made for an oral probiotic for preservation/restoration of the microbiome. Lastly, we would recommend against high-dose vitamin supplementation and only support vitamin supplementation that is directed at rectifying a recorded deficiency (including micronutrients such as selenium and zinc). Compliance with Ethical Standards Conflict of Interest There are no financial or non-financial conflicts of interest for all collaborating authors. Human and Animal Rights and Informed Consent This article does not contain any studies with human or animal subjects performed by any of the authors. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance 1. WHO Coronavirus (COVID-19) Dashboard: World Health Organization 2022 [updated September 20, 2022, September 22, 2022]. 2. CDC Museum COVID-19 Timeline Center for Disease Control and Prevention David J. Sencer CDC Museum: In Association with the Smithsonian Institution; 2022 [updated August 16, 2022, September 1, 2022]. 3. Lighter J Phillips M Hochman S Sterling S Johnson D Francois F Obesity in patients younger than 60 years is a risk factor for COVID-19 hospital admission Clin Infect Dis 2020 71 15 896 897 10.1093/cid/ciaa415 32271368 4. Popkin BM Du S Green WD Beck MA Algaith T Herbst CH Individuals with obesity and COVID-19: a global perspective on the epidemiology and biological relationships Obes Rev 2020 21 11 e13128 10.1111/obr.13128 32845580 5. Tariq R Saha S Furqan F Hassett L Pardi D Khanna S Prevalence and mortality of COVID-19 patients with gastrointestinal symptoms: a systematic review and meta-analysis Mayo Clin Proc 2020 95 8 1632 1648 10.1016/j.mayocp.2020.06.003 32753138 6. Silva F Brito BB Santos MLC Marques HS Silva Junior RTD Carvalho LS COVID-19 gastrointestinal manifestations: a systematic review Rev Soc Bras Med Trop 2020 53 e20200714 10.1590/0037-8682-0714-2020 33263693 7. Kaafarani HMA El Moheb M Hwabejire JO Naar L Christensen MA Breen K Gastrointestinal complications in critically ill patients with COVID-19 Ann Surg 2020 272 2 e61 e62 10.1097/SLA.0000000000004004 32675498 8. Coronaviridae Study Group of the International Committee on Taxonomy of V. The species severe acute respiratory syndrome-related coronavirus: classifying 2019-nCoV and naming it SARS-CoV-2. Nat Microbiol. 2020;5(4):536–44. 9. Lan J Ge J Yu J Shan S Zhou H Fan S Structure of the SARS-CoV-2 spike receptor-binding domain bound to the ACE2 receptor Nature 2020 581 7807 215 220 10.1038/s41586-020-2180-5 32225176 10. Dong M Zhang J Ma X Tan J Chen L Liu S ACE2, TMPRSS2 distribution and extrapulmonary organ injury in patients with COVID-19 Biomed Pharmacother 2020 131 110678 10.1016/j.biopha.2020.110678 32861070 11. Hamming I, Timens W, Bulthuis ML, Lely AT, Navis G, van Goor H. Tissue distribution of ACE2 protein, the functional receptor for SARS coronavirus. A first step in understanding SARS pathogenesis. J Pathol. 2004;203(2):631–7. 12. H AA, Imam Rabbani S. COVID-19: a review on the role of trace elements present in Saudi Arabian traditional dietary supplements. Pak J Biol Sci. 2022;25(1):1–8. 13. Allali I Bakri Y Amzazi S Ghazal H Gut-lung axis in COVID-19 Interdiscip Perspect Infect Dis 2021 2021 6655380 10.1155/2021/6655380 33777139 14. Zeng W Qi K Ye M Zheng L Liu X Hu S Gastrointestinal symptoms are associated with severity of coronavirus disease 2019: a systematic review and meta-analysis Eur J Gastroenterol Hepatol 2022 34 2 168 176 10.1097/MEG.0000000000002072 33470700 15. Wang Y Li Y Zhang Y Liu Y Liu Y Are gastrointestinal symptoms associated with higher risk of mortality in COVID-19 patients? A systematic review and meta-analysis BMC Gastroenterol 2022 22 1 106 10.1186/s12876-022-02132-0 35255816 16. Blackett JW Li J Jodorkovsky D Freedberg DE Prevalence and risk factors for gastrointestinal symptoms after recovery from COVID-19 Neurogastroenterol Motil 2022 34 3 e14251 10.1111/nmo.14251 34468069 17. El Moheb M Naar L Christensen MA Kapoen C Maurer LR Farhat M Gastrointestinal complications in critically ill patients with and without COVID-19 JAMA 2020 324 18 1899 1901 10.1001/jama.2020.19400 32970139 18. Ren P Gong C Ma S Evaluation of COVID-19 based on ACE2 expression in normal and cancer patients Open Med (Wars) 2020 15 1 613 622 10.1515/med-2020-0208 33336018 19. Zhang H Li HB Lyu JR Lei XM Li W Wu G Specific ACE2 expression in small intestinal enterocytes may cause gastrointestinal symptoms and injury after 2019-nCoV infection Int J Infect Dis 2020 96 19 24 10.1016/j.ijid.2020.04.027 32311451 20. Gaebler C Wang Z Lorenzi JCC Muecksch F Finkin S Tokuyama M Evolution of antibody immunity to SARS-CoV-2 Nature 2021 591 7851 639 644 10.1038/s41586-021-03207-w 33461210 21. Schirmer M Smeekens SP Vlamakis H Jaeger M Oosting M Franzosa EA Linking the human gut microbiome to inflammatory cytokine production capacity Cell 2016 167 7 1897 10.1016/j.cell.2016.11.046 27984736 22. Xu X Zhang W Guo M Xiao C Fu Z Yu S Integrated analysis of gut microbiome and host immune responses in COVID-19 Front Med 2022 16 2 263 275 10.1007/s11684-022-0921-6 35258762 23. Tang L Gu S Gong Y Li B Lu H Li Q Clinical significance of the correlation between Changes in the major intestinal bacteria species and COVID-19 severity Engineering (Beijing) 2020 6 10 1178 1184 33520333 24. Zuo T, Zhang F, Lui GCY, Yeoh YK, Li AYL, Zhan H, et al. Alterations in gut microbiota of patients with COVID-19 during time of hospitalization. Gastroenterology. 2020;159(3):944–55 e8. 25. •• Zuo T, Wu X, Wen W, Lan P. Gut microbiome alterations in COVID-19. Genomics Proteomics Bioinformatics. 2021;19(5):679–88. This article was the first to describe dramatic changes in fecal microbiota in those suffering from COVID-19. Also described was the persistence of microbiota alterations even after COVID-19 resolution. Lastly, the article postulates the role of the fecal microbiome alteration in the inflammatory and immune response. Overall, this article was the flagship publication in COVID-19-induced fecal microbiome alteration. 26. Gu S Chen Y Wu Z Chen Y Gao H Lv L Alterations of the gut microbiota in patients with coronavirus disease 2019 or H1N1 influenza Clin Infect Dis 2020 71 10 2669 2678 10.1093/cid/ciaa709 32497191 27. • Yeoh YK, Zuo T, Lui GC, Zhang F, Liu Q, Li AY, et al. Gut microbiota composition reflects disease severity and dysfunctional immune responses in patients with COVID-19. Gut. 2021;70(4):698–706. This article describes the role of the fecal microbiome in COVID-19 severity. This study was able to find an association between fecal microbiome alterations and levels of inflammatory markers in COVID-19 sufferers. The article was able to illustrate the influence of gut composition on inflammation and COVID severity. 28. Zhang L Han H Li X Chen C Xie X Su G Probiotics use is associated with improved clinical outcomes among hospitalized patients with COVID-19 Therap Adv Gastroenterol 2021 14 17562848211035670 10.1177/17562848211035670 34394726 29. Wang H Wang Y Lu C Qiu L Song X Jia H The efficacy of probiotics in patients with severe COVID-19 Ann Palliat Med 2021 10 12 12374 12380 10.21037/apm-21-3373 35016484 30. Kullar R, Johnson S, McFarland LV, Goldstein EJC. Potential roles for probiotics in the treatment of COVID-19 patients and prevention of complications associated with increased antibiotic use. Antibiotics (Basel). 2021;10(4). 31. Liu F Ye S Zhu X He X Wang S Li Y Gastrointestinal disturbance and effect of fecal microbiota transplantation in discharged COVID-19 patients J Med Case Rep 2021 15 1 60 10.1186/s13256-020-02583-7 33557941 32. Bilinski J Winter K Jasinski M Szczes A Bilinska N Mullish BH Rapid resolution of COVID-19 after faecal microbiota transplantation Gut 2022 71 1 230 232 10.1136/gutjnl-2021-325010 34230217 33. Nejadghaderi SA Nazemalhosseini-Mojarad E Asadzadeh AH Fecal microbiota transplantation for COVID-19; a potential emerging treatment strategy Med Hypotheses 2021 147 110476 10.1016/j.mehy.2020.110476 33482620 34. Tuso P Stoll SR Li WW A plant-based diet, atherogenesis, and coronary artery disease prevention Perm J 2015 19 1 62 67 10.7812/TPP/14-036 25431999 35. McMacken M Shah S A plant-based diet for the prevention and treatment of type 2 diabetes J Geriatr Cardiol 2017 14 5 342 354 28630614 36. Kim H Rebholz CM Hegde S LaFiura C Raghavan M Lloyd JF Plant-based diets, pescatarian diets and COVID-19 severity: a population-based case-control study in six countries BMJ Nutr Prev Health 2021 4 1 257 266 10.1136/bmjnph-2021-000272 34308134 37. Gangitano E, Tozzi R, Gandini O, Watanabe M, Basciani S, Mariani S, et al. Ketogenic diet as a preventive and supportive care for COVID-19 patients. Nutrients. 2021;13(3). 38. Sukkar SG Bassetti M Induction of ketosis as a potential therapeutic option to limit hyperglycemia and prevent cytokine storm in COVID-19 Nutrition 2020 79–80 110967 10.1016/j.nut.2020.110967 32942131 39. Gangitano E Tozzi R Mariani S Lenzi A Gnessi L Lubrano C Ketogenic diet for obese COVID-19 patients: is respiratory disease a contraindication? A narrative review of the literature on ketogenic diet and respiratory function Front Nutr 2021 8 771047 10.3389/fnut.2021.771047 34957183 40. Romagnolo DF Selmin OI Mediterranean diet and prevention of chronic diseases Nutr Today 2017 52 5 208 222 10.1097/NT.0000000000000228 29051674 41. Angelidi AM Kokkinos A Katechaki E Ros E Mantzoros CS Mediterranean diet as a nutritional approach for COVID-19 Metabolism 2021 114 154407 10.1016/j.metabol.2020.154407 33080270 42. Calatayud FM Calatayud B Gallego JG Gonzalez-Martin C Alguacil LF Effects of Mediterranean diet in patients with recurring colds and frequent complications Allergol Immunopathol (Madr) 2017 45 5 417 424 10.1016/j.aller.2016.08.006 27939720 43. Ponzo V, Pellegrini M, D'Eusebio C, Bioletto F, Goitre I, Buscemi S, et al. Mediterranean diet and SARS-COV-2 infection: is there any association? A proof-of-concept study. Nutrients. 2021;13(5). 44. Perez-Araluce R Martinez-Gonzalez MA Gea A Carlos S Components of the Mediterranean diet and risk of COVID-19 Front Nutr 2021 8 805533 10.3389/fnut.2021.805533 35141266 45. Patel JJ Martindale RG McClave SA Relevant nutrition therapy in COVID-19 and the constraints on its delivery by a unique disease process Nutr Clin Pract 2020 35 5 792 799 10.1002/ncp.10566 32786117 46. Osuna-Padilla I Rodriguez-Moguel NC Aguilar-Vargas A Rodriguez-Llamazares S Safety and tolerance of enteral nutrition in COVID-19 critically ill patients, a retrospective study Clin Nutr ESPEN 2021 43 495 500 10.1016/j.clnesp.2021.02.015 34024561 47. Ojo O Enteral feeding for nutritional support in critically ill patients Br J Nurs 2017 26 12 666 669 10.12968/bjon.2017.26.12.666 28640724 48. • Ojo O, Ojo OO, Feng Q, Boateng J, Wang X, Brooke J, et al. The effects of enteral nutrition in critically ill patients with COVID-19: a systematic review and meta-analysis. Nutrients. 2022;14(5). This systematic review concluded that early adoption of enteral nutrition in critically ill COVID-19 patients improved outcomes. Specifically, early enteral nutrition was found to significantly impact mortality; however, there was no significant impact in regard to the length of hospitalization, ICU stay, or mechanical ventilation duration. 49. Zhang J Rao X Li Y Zhu Y Liu F Guo G Pilot trial of high-dose vitamin C in critically ill COVID-19 patients Ann Intensive Care 2021 11 1 5 10.1186/s13613-020-00792-3 33420963 50. Al Sulaiman K Aljuhani O Saleh KB Badreldin HA Al Harthi A Alenazi M Ascorbic acid as an adjunctive therapy in critically ill patients with COVID-19: a propensity score matched study Sci Rep 2021 11 1 17648 10.1038/s41598-021-96703-y 34480041 51. Thomas S Patel D Bittel B Wolski K Wang Q Kumar A Effect of high-dose zinc and ascorbic acid supplementation vs usual care on symptom length and reduction among ambulatory patients with SARS-CoV-2 infection: the COVID A to Z Randomized Clinical Trial JAMA Netw Open 2021 4 2 e210369 10.1001/jamanetworkopen.2021.0369 33576820 52. Gavrielatou E Xourgia E Xixi NA Mantelou AG Ischaki E Kanavou A Effect of vitamin C on clinical outcomes of critically ill patients with COVID-19: an observational study and subsequent meta-analysis Front Med (Lausanne) 2022 9 814587 10.3389/fmed.2022.814587 35223911 53. Kwak SG Choo YJ Chang MC The effectiveness of high-dose intravenous vitamin C for patients with coronavirus disease 2019: a systematic review and meta-analysis Complement Ther Med 2022 64 102797 10.1016/j.ctim.2021.102797 34953366 54. Ao G Li J Yuan Y Wang Y Nasr B Bao M Intravenous vitamin C use and risk of severity and mortality in COVID-19: a systematic review and meta-analysis Nutr Clin Pract 2022 37 2 274 281 10.1002/ncp.10832 35148440 55. Fakhrolmobasheri M Mazaheri-Tehrani S Kieliszek M Zeinalian M Abbasi M Karimi F COVID-19 and selenium deficiency: a systematic review Biol Trace Elem Res 2022 200 9 3945 3956 10.1007/s12011-021-02997-4 34739678 56. Balboni E Zagnoli F Filippini T Fairweather-Tait SJ Vinceti M Zinc and selenium supplementation in COVID-19 prevention and treatment: a systematic review of the experimental studies J Trace Elem Med Biol 2022 71 126956 10.1016/j.jtemb.2022.126956 35217499 57. Zhang HY Zhang AR Lu QB Zhang XA Zhang ZJ Guan XG Association between fatality rate of COVID-19 and selenium deficiency in China BMC Infect Dis 2021 21 1 452 10.1186/s12879-021-06167-8 34011281 58. Razeghi Jahromi S Moradi Tabriz H Togha M Ariyanfar S Ghorbani Z Naeeni S The correlation between serum selenium, zinc, and COVID-19 severity: an observational study BMC Infect Dis 2021 21 1 899 10.1186/s12879-021-06617-3 34479494 59. Petrelli F Luciani A Perego G Dognini G Colombelli PL Ghidini A Therapeutic and prognostic role of vitamin D for COVID-19 infection: a systematic review and meta-analysis of 43 observational studies J Steroid Biochem Mol Biol 2021 211 105883 10.1016/j.jsbmb.2021.105883 33775818 60. Dissanayake HA de Silva NL Sumanatilleke M de Silva SDN Gamage KKK Dematapitiya C Prognostic and therapeutic role of vitamin D in COVID-19: systematic review and meta-analysis J Clin Endocrinol Metab 2022 107 5 1484 1502 10.1210/clinem/dgab892 34894254 61. Villasis-Keever MA, Lopez-Alarcon MG, Miranda-Novales G, Zurita-Cruz JN, Barrada-Vazquez AS, Gonzalez-Ibarra J, et al. Efficacy and safety of vitamin D supplementation to prevent COVID-19 in frontline healthcare workers. A randomized clinical trial. Arch Med Res. 2022;53(4):423–30. 62. • Jolliffe DA, Camargo CA, Jr., Sluyter JD, Aglipay M, Aloia JF, Ganmaa D, et al. Vitamin D supplementation to prevent acute respiratory infections: a systematic review and meta-analysis of aggregate data from randomised controlled trials. Lancet Diabetes Endocrinol. 2021;9(5):276–92. This randomized control study displayed no significant benefit to vitamin D supplementation in the prevention of COVID-19. With over 6000 participants, this was one of the largest studies of its kind. While there is a mechanism-based indication that vitamin D is beneficial in viral infection prevention, future high-quality studies like this one will be needed to support this postulation. 63. Brunvoll SH Nygaard AB Ellingjord-Dale M Holland P Istre MS Kalleberg KT Prevention of covid-19 and other acute respiratory infections with cod liver oil supplementation, a low dose vitamin D supplement: quadruple blinded, randomised placebo controlled trial BMJ 2022 378 e071245 10.1136/bmj-2022-071245 36215222 64. Entrenas Castillo M Entrenas Costa LM Vaquero Barrios JM Alcala Diaz JF Lopez Miranda J Bouillon R Effect of calcifediol treatment and best available therapy versus best available therapy on intensive care unit admission and mortality among patients hospitalized for COVID-19: a pilot randomized clinical study J Steroid Biochem Mol Biol 2020 203 105751 10.1016/j.jsbmb.2020.105751 32871238
PMC009xxxxxx/PMC9999321.txt	==== Front Sci China Life Sci Sci China Life Sci Science China. Life Sciences 1674-7305 1869-1889 Science China Press Beijing 36897494 2294 10.1007/s11427-023-2294-5 Insight SARS-CoV-2 shows a much earlier divergence in the world than in the Chinese mainland Cheng Chaoyuan 1 Zhang Zhibin [email protected] 12 1 grid.9227.e 0000000119573309 State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China 2 grid.410726.6 0000 0004 1797 8419 CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049 China 7 3 2023 2023 66 6 14401443 2 1 2023 12 2 2023 © Science China Press 2023 This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. issue-copyright-statement© Science China Press 2023 ==== Body pmcSupporting Information SARS-CoV-2 shows a much earlier divergence in the world than in the Chinese mainland Supplementary material, approximately 13.3 MB. Acknowledgements The work was supported by the Ministry of Science and Technology of the People’s Republic of China (2021YFC0863400), and the Institute of Zoology, Chinese Academy of Science (E0517111, E122G611). Methods, discussion, and data are attached in Supplementary Information. Compliance and ethics The author(s) declare that they have no conflict of interest. ==== Refs References Drummond A Pybus OG Rambaut A Inference of viral evolutionary rates from molecular sequences Adv Parasitol 2003 54 331 358 10.1016/S0065-308X(03)54008-8 14711090 Pekar J Worobey M Moshiri N Scheffler K Wertheim JO Timing the SARS-CoV-2 index case in Hubei province Science 2021 372 412 417 10.1126/science.abf8003 33737402 van Dorp L Acman M Richard D Shaw LP Ford CE Ormond L Owen CJ Pang J Tan CCS Boshier FAT Emergence of genomic diversity and recurrent mutations in SARS-CoV-2 Infect Genet Evol 2020 83 104351 10.1016/j.meegid.2020.104351 32387564
PMC010xxxxxx/PMC10008191.txt	==== Front Indian J Gynecol Oncol Indian J Gynecol Oncol Indian Journal of Gynecologic Oncology 2363-8397 2363-8400 Springer India New Delhi 36937898 706 10.1007/s40944-023-00706-8 Case Report Pancreatic Choristoma in Omentum in Advanced CA Ovary: A Clinical Puzzle Sharma Munisha [email protected] 1 http://orcid.org/0000-0002-9694-7332 Annapurna Vadaparty [email protected] [email protected] 1 Sulakshana Managanahalli Srihari 2 Rekha B. R. 1 1 Department of Gynecologic Oncology, Sri Shankara Cancer Hospital and Research Centre, Bengaluru, India 2 Department of Oncopathology, Sri Shankara Cancer Hospital and Research Centre, Bengaluru, India 12 3 2023 2023 21 2 327 12 2022 7 12 2022 16 1 2023 © The Author(s) under exclusive licence to Association of Gynecologic Oncologists of India 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Ectopic pancreatic tissue is called pancreatic choristoma or heterotopia of pancreas. It is a rare entity. We present a case of advanced Ca ovary with omental pancreatic choristoma. Keywords Pancreatic choristoma Ovarian cancer Clinical features issue-copyright-statement© Association of Gynecologic Oncologists of India 2023 ==== Body pmcIntroduction Pancreatic choristoma is a congenital anomaly. Herein, the pancreatic tissue without any anatomical or vascular connections to the main pancreas is found in ectopic location. It is relatively a rare entity, found at laparotomy with an incidence of 0.2% (Elpek 2007). The pancreatic choristoma can be found in various anatomical sites such as the stomach, duodenum, jejunum, gallbladder, esophagus, common bile duct, spleen, mesentery, mediastinum, lungs and fallopian tubes. Stomach is the most common location (25 to 38%), with pancreatic rests most frequently found in the submucosa (75% of cases) (Elhence 2012). Although ectopic pancreas is usually an incidental finding, they can present with nonspecific symptoms such as abdominal pain, abdominal fullness, nausea, vomiting, anorexia, weight loss, anemia, and melena. Abdominal pain is the most common symptomatic presentation and can be explained by the inflammation and irritation of surrounding tissues secondary to the secretion of pancreatic enzymes and hormones. Pain can also be explained as a result of hemorrhage in the lesion due to mucosal erosion and ulcer formation, especially when it occurs in the small intestine. Patients can also present with symptoms of gastric outlet obstruction especially those greater than 1.5 cm in size. Published literature reports have described rare instances of malignant transformation in the ectopic pancreatic tissue (Pendharkar 2019). We present a case of pancreatic choristoma in the omentum, in a case of epithelial ovarian Ca. Case A 54-year-old lady presented to our OPD with abdominal distension, breathlessness, inability to eat for last 2 months, in the COVID-19 pandemic days, April, 2020. She also gave a longstanding history of dyspepsia, bloating and diarrhea on and off. Clinical examination revealed a cachectic lady with a ECOG performance score 2, massive ascites and bilateral pedal edema. Her CA125 value was more than 2000 U/ml at first visit, serum albumin 3.6 g%. PET-CT done elsewhere showed multiple discrete coalescent peritoneal, omental and mesenteric soft tissue deposits with caking, massive ascites, prominent retrocaval, perigastric, intramammary, mediastinal nodes. Ascitic fluid tapping was done and sent for malignant cytology, cell block analysis. The report was positive for malignant cells, adenocarcinoma cells. A working diagnosis of advanced ovarian Ca was made and planned for neoadjuvant chemotherapy followed by interval debulking surgery. Dose dense weekly Paclitaxel 80 mg/m2 and Carboplatin AUC 2 was administered for 9 weeks, starting from 6/5/2020. At the end of 9 weeks, there was partial clinical response. The massive ascites had become mild ascites but patient had not had much improvement in symptoms of loose motions and dyspepsia. Her CA 125 had decreased from more than 2000U/ml to 246 U/ml. A PET-CT was repeated to assess her response to treatment and revealed partial response to the therapy. She underwent interval debulking surgery on 15/9/2020. Laparotomy, TAH + BSO + pelvic peritonectomy and total omentectomy were performed. There was no gross residual disease left at the end of surgery. Her PCI score was 8/39. She had received prophylactic antibiotics, anticoagulants as per hospital protocol (Fig. 1).Fig. 1 Omentum displaying gray white tumor During surgery total omentectomy, dissection was difficult near splenic flexure, as there was a residual tumor in the omentum near splenic hilum, of around 5 cm. There were dense adhesions between the tumor mass in omentum and the anterior surface of the pancreas. Complete debulking was done. The first 2 days post-op period was uneventful—with patient on normal diet and ambulating from post-op day 1. On post-op day 3, patient developed one episode of high-grade fever, persistent diarrhea and chest congestion symptoms. She was treated symptomatically for next 3 days. Fever had subsided in 24 h but diarrhea persisted. Covid RT-PCR was done twice during the 7 days post-op period. Both the Covid RT-PCR reports were negative. Her white blood counts were on higher side of range, 17,000–21,000/mm3, with neutrophilic leukocytosis all throughout the hospital stay. The inflammatory marker serum procalcitonin (PCT) increased steadily from 5 to 18 ng/ml, from post-op day 6 to 11, (normal value for serum procalcitonin- < 0.5 ng/ml, serum PCT > 2 ng/ml—sepsis, serum PCT values increase post laparotomy). Work up for possible source of sepsis was done, and reports were non-contributory. Patient was started on higher antibiotics for raised PCT. Clinically, patient was not looking as ill as her blood reports. There were no more episodes of fever during her hospital stay. She was discharged on 11th post-op day, ambulating, with symptoms of diarrhea partially subsiding. The patient returned on POD 14 for suture removal. Wound had healed well. Histopathology showed HGSC ovary with pancreatic choristoma in omentum. Based on Heinrich’s 1909* classification and the subsequent Gasper-Fuentes modification in 1973, there are four types of pancreatic heterotopia. They areType I—typical pancreatic tissue with acini, ducts, and islet cells similar to the normal pancreas. Type II (canalicular variety)—pancreatic ducts only. Type III (exocrine pancreas)—acinar tissue only. Type IV (endocrine pancreas)—islet cells only. Our patient belonged to first type with pancreatic tissue, acini, ducts and islet cells (Fig. 2).Fig. 2 Omentum displaying a gray-tan nodule resembling pancreatic parenchyma She was advised to complete the adjuvant treatment as advised. She was lost to follow-up after completion of treatment. Discussion The clinical presentation of the ectopic pancreas and ovarian carcinoma has many similarities. Our patient had irritable bowel syndrome for the last 10–12 years. In ovarian cancer, we do find the symptoms of constipation, loose motions, weight loss, bloating sensation, loss of appetite for a few months prior to diagnosis of Ca ovary. Hence, the GI symptomatology was thought to be of ovarian origin, but a bit exaggerated. But retrospectively, we found that watery diarrhea is a less common symptom for Ca ovary than constipation (Fig. 3). Fig. 3 Fibroadipose tissue with pancreatic acini During the postoperative period, patient continued to have diarrhea and pain abdomen in the left hypochondrium, which was attributed to the surgical procedure. The symptom of persistent diarrhea was thought to be due to covid, in the pandemic time. The persistent leukocytosis and elevated serum procalcitonin made us prescribe higher antibiotics during the 11-day hospital stay (Fig. 4). Fig. 4 Pancreatic acini with islets and ductules Omental pancreatic choristoma is a rare occurrence, and the diagnosis was revealed after the patient got discharged! This case helped us to know about pancreatic choristoma, and the clinical picture could then be correlated with laboratory reports. The raised serum PCT and leukocytosis could be due to inflammation due to choristoma and surgical dissection. Declarations Conflict of interest The authors declare that they have no conflict of interest. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Elpek GO Bozova S Küpesiz GY Oğüş M An unusual cause of cholecystitis: heterotopic pancreatic tissue in the gallbladder World J Gastroenterol 2007 13 2 313 315 10.3748/wjg.v13.i2.313 17226916 2. Elhence P Bansal R Agrawal N Heterotopic pancreas in gall bladder associated with chronic cholecystolithiasis Int J Appl Basic Med Res 2012 2 2 142 143 10.4103/2229-516X.106360 23776830 3. Pendharkar D Khetrapal S Jairajpuri ZS Rana S Jetley S Pancreatic and gastric heterotopia in the gallbladder: a rare incidental finding Int J Appl Basic Med Res 2019 9 2 115 117 10.4103/ijabmr.IJABMR_109_18 31041176
PMC010xxxxxx/PMC10008800.txt	==== Front Educacio´n Me´dica 1575-1813 1579-2099 The Author(s). Published by Elsevier España, S.L.U. S1575-1813(23)00018-9 10.1016/j.edumed.2023.100808 100808 Carta al Director Experiencia con la educación sincrónica en una universidad pública peruana durante la pandemia por COVID-19 Experience with synchronous distance education at Peruvian public university during the COVID-19 pandemicMunayco-Pantoja Evelyn R. ab⁎ Castañeda Sarmiento Sara a Gálvez Ramírez Carlos Michell a Mezarina Mendoza Jhon Paul Iakov a a Facultad de Odontología, Universidad Nacional Mayor de San Marcos, Lima, Perú b Unidad de Investigación en Enfermedades Emergentes y Cambio Climático, Facultad de Salud Pública y Administración, Universidad Peruana Cayetano Heredia, Lima, Perú ⁎ Autor para correspondencia. 13 3 2023 May-June 2023 13 3 2023 24 3 100808100808 20 12 2022 13 2 2023 © 2023 The Author(s) 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcSeñor director: Hemos revisado atentamente el manuscrito que analiza la preocupación sobre la educación durante la pandemia por COVID-19 y queremos compartir nuestra experiencia con la educación sincrónica, como docentes de pregrado, en la Facultad de Odontología de una universidad pública en Perú. Debido a las restricciones por la pandemia, en el curso de odontopediatría, se empleó una educación híbrida con actividades sincrónicas (80%) y asincrónicas (20%). Ladewig et al.1 mencionan que el 68,3% de los estudiantes encuestados deseaban recibir ambos métodos de enseñanza, sin embargo, solo la mitad los recibió (35,32%). Nosotros opinamos que para mejorar la experiencia de aprendizaje se debe explorar previamente las preferencias de los estudiantes, tal y como lo hicimos en el año 2022. Diseñamos un taller que se inspiró en un artículo científico publicado en el 20192. Este estuvo compuesto por una sesión de aprendizaje teórica y práctica mediante la plataforma Google Meet. El tema tratado durante la sesión teórica fue defectos del desarrollo del esmalte (DDE) en dentición decidua y permanente joven, los cuales tienen una prevalencia en la población de 74,2%3 y 20,59%4, respectivamente. Una semana después, se realizó la sesión práctica, basada en el aprendizaje adaptativo con casos clínicos. Esta metodología es preferida por el 57,6% de los estudiantes de ciencias de la salud, según Ladewig et al1. Participaron 61 estudiantes del VI semestre, la edad promedio fue de 21 años, no habían llevado ninguna sesión de aprendizaje teórico o práctico anteriormente sobre el tema dictado (78,7%) y no tenían experiencia en el campo clínico (70,5%). Además, todos los cursos fueron virtuales desde el inicio de su educación universitaria. Características similares a la población de estudio de Ladewig et al.1, excepto que nuestros participantes fueron, en mayor proporción, de género femenino (60,7%). Respecto al conocimiento adquirido en línea, mediante el taller, se logró una tasa de acierto por pieza dentaria, superficie y diagnóstico de DDE de 57,9%, 95,08% y 64,84%, respectivamente, lo cual indicaría que los conceptos clínicos son adecuadamente comprendidos por los estudiantes. Sin embargo, este método de aprendizaje no reemplaza a la enseñanza presencial, ya que el 88,91% de los estudiantes opina que los conocimientos adquiridos virtualmente son insuficientes para resolver situaciones del entorno laboral1. Nosotros sugerimos utilizar más de un método educativo para mejorar el aprendizaje virtual. En conclusión, aunque existe literatura que afirma que el 87,5% de los estudiantes de odontología no está satisfecho con la educación virtual5 y 2 tercios de ellos consideran que su formación práctica se verá afectada6, nosotros recomendamos el aprendizaje adaptativo con casos clínicos para la enseñanza de aspectos desarrollados en el ámbito clínico a estudiantes de odontología, siempre y cuando se complemente con otras estrategias educativas. Responsabilidades éticas El presente estudio cuenta con la aprobación del Comité de Ética Institucional, además cada participante firmó un consentimiento informado autorizando su participación. Financiación Ninguna. Conflicto de intereses Los autores declaran no tener ningún conflicto de intereses. ==== Refs Bibliografía 1 Ladewig Bernáldez G.I., Pérez Vázquez S.I., González Delgado A. and Flores Pacheco N.A., Preocupaciones sobre la educación de los estudiantes de ciencias de la salud durante la pandemia por SARS-CoV-2, Educ Méd, 23 (2), 2022, 100729. Disponible en: 10.1016/j.edumed.2022.100729, [consultado 7 Ago 2022]. 2 Jälevik B., Szigyarto-Matei A. and Robertson A., Difficulties in identifying developmental defects of the enamel: a BITA study, Eur Arch Paediatr Dent, 20 (5), 2019, 481–488. Disponible en: 10.1007/s40368-019-00431-x, [consultado 7 Ago 2022]. 3. Osorio-Tovar J.P. Naranjo-Sierra M.C. Rodríguez-Godoy M. Prevalencia de defectos de desarrollo del esmalte en dentición temporal, en una población bogotana Rev Salud Pública 18 6 2016 Dec 963 975 Disponible en http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0124-00642016000600963&lng=en10.15446/rsap.v18n6.48090 10.15446/rsap.v18n6.48090 [consultado 7 Ago 2022] 30137179 4 Fleites Ramos Y. González Duardo K. Rico Pérez A.M. Pacheco Avellanes M. del Toro Vega L. Prevalencia de los defectos del desarrollo del esmalte en la dentición permanente Medic Electr 23 3 2019 Sep 177 191 Disponible en http://scielo.sld.cu/scielo.php?script=sci_arttext&pid=S1029-30432019000300177&lng=es [consultado 7 Ago 2022] 5 Islam M.I. Jahan S.S. Chowdhury M.T.H. Isha S.N. Saha A.K. Nath S.K. Experience of Bangladeshi dental students towards online learning during the COVID-19 pandemic: a web-based cross-sectional study Int J Environ Res Public Health 19 13 2022 7786 Disponible en 10.3390/ijerph19137786 [consultado 7 Ago 2022] 35805442 6 Iurcov R. Pop L.-M. Iorga M. Impact of COVID-19 pandemic on academic activity and health status among Romanian medical dentistry students; A cross-sectional study Int J Environ Res Public Health 18 11 2021 6041 Disponible en 10.3390/ijerph18116041 [consultado 7 Ago 2022] 34199729
PMC010xxxxxx/PMC10009868.txt	==== Front Biomech Model Mechanobiol Biomech Model Mechanobiol Biomechanics and Modeling in Mechanobiology 1617-7959 1617-7940 Springer Berlin Heidelberg Berlin/Heidelberg 36913005 1691 10.1007/s10237-023-01691-9 Original Paper Comparison of optimization parametrizations for regional lung compliance estimation using personalized pulmonary poromechanical modeling Laville Colin [email protected] 12 Fetita Catalin [email protected] 3 Gille Thomas [email protected] 45 Brillet Pierre-Yves [email protected] 45 Nunes Hilario [email protected] 45 Bernaudin Jean-François [email protected] 4 Genet Martin [email protected] 12 1 grid.463926.c 0000 0001 2287 9755 Laboratoire de Mécanique des Solides, École Polytechnique/CNRS/IPP, Palaiseau, France 2 grid.457355.5 Inria, Palaiseau, France 3 grid.29773.38 0000 0001 2202 567X SAMOVAR, Télécom SudParis/IMT/IPP, Évry, France 4 grid.462844.8 0000 0001 2308 1657 Hypoxie et Poumon, Université Sorbonne Paris Nord/INSERM, Bobigny, France 5 grid.413780.9 0000 0000 8715 2621 Hôpital Avicenne, APHP, Bobigny, France 13 3 2023 114 30 9 2022 9 1 2023 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Interstitial lung diseases, such as idiopathic pulmonary fibrosis (IPF) or post-COVID-19 pulmonary fibrosis, are progressive and severe diseases characterized by an irreversible scarring of interstitial tissues that affects lung function. Despite many efforts, these diseases remain poorly understood and poorly treated. In this paper, we propose an automated method for the estimation of personalized regional lung compliances based on a poromechanical model of the lung. The model is personalized by integrating routine clinical imaging data – namely computed tomography images taken at two breathing levels in order to reproduce the breathing kinematic—notably through an inverse problem with fully personalized boundary conditions that is solved to estimate patient-specific regional lung compliances. A new parametrization of the inverse problem is introduced in this paper, based on the combined estimation of a personalized breathing pressure in addition to material parameters, improving the robustness and consistency of estimation results. The method is applied to three IPF patients and one post-COVID-19 patient. This personalized model could help better understand the role of mechanics in pulmonary remodeling due to fibrosis; moreover, patient-specific regional lung compliances could be used as an objective and quantitative biomarker for improved diagnosis and treatment follow up for various interstitial lung diseases. Keywords Pulmonary mechanics Poromechanics Finite element method Image-based estimation Optimization http://dx.doi.org/10.13039/501100001665 Agence Nationale de la Recherche ANR-10-EQPX-37 ANR-20-COV4-0004 ANR-20-COV4-0004 ANR-20-COV4-0004 ANR-20-COV4-0004 ANR-20-COV4-0004 ANR-10-EQPX-37 Laville Colin Fetita Catalin Gille Thomas Brillet Pierre-Yves Nunes Hilario Bernaudin Jean-François Genet Martin ==== Body pmcIntroduction Idiopathic pulmonary fibrosis (IPF) is still today a poorly understood disease, characterized by the thickening and stiffening of lung interstitial tissues (Nunes et al. 2015, Plantier et al. 2018). It is a severe chronic disease leading to progressive and irreversible deterioration of lung function due to impaired gas exchange, with very few available treatments (Flaherty et al. 2018). As the disease progresses, patients suffer from persistent and increasing symptoms of dyspnea, dry cough, chest pain, fatigue, etc. (Flaherty et al. 2018). More recently, post-COVID-19 pulmonary fibrosis has been frequently reported (George et al. 2020, Giacomelli et al. 2021). About 8% of patients present severe lung capacity impairment, chest pain, painful muscles, ageusia, anosmia or fibrotic damage that could be attributed to the COVID-19 infection (Ballering et al. 2022). The severity of the initial symptoms is correlated with a higher risk of persistent respiratory complications (McGroder et al. 2021). These long-term complications may cause substantial patients disability and even death due to lung fibrosis progression in the following years, and thus drastically increase pulmonary fibrosis prevalence (Michalski et al. 2022). Like in other clinical fields (Smith et al. 2011, Lee et al. 2014), patient-specific numerical models are intended to play a role in such clinical issues, through individualized diagnosis, prognosis and long term follow up, evaluating effectiveness of a treatment over time from a mechanical point of view (Roth et al. 2017, Morton et al. 2018). Moreover, they could give additional information to clinicians in order to propose individualized therapies. Regarding post-COVID-19 patients, these models may help for early detection of pulmonary fibrosis. Pulmonary fibrosis is also associated to more fundamental issues. For instance, the underlying mechanisms involved in progression and worsening over time are not fully understood. One of the hypotheses is the existence of a mechanical vicious circle (Liu et al. 2010, Carloni et al. 2013, Wu et al. 2020). According to this assumption, the thickening of the interstitial tissues due to pulmonary fibrosis locally increases its rigidity inducing higher stresses, which activates the production of collagen fibers by fibroblasts in the surrounding area (Liu et al. 2015). Only a few studies have tried to evaluate this hypothesis. A possible investigative approach, that we will sustain in this paper, is through personalized biomechanical modeling of fibrotic lungs based on medical imaging. Numerical modeling of lungs, and especially finite-element modeling, have been widely used in the literature to study air flow and gas exchange (Neelakantan et al. 2022). At a more general level including mechanical deformation and fluid-solid interaction, it is an active research field that aims to understand the biomechanics of the lung and its function under normal and pathological conditions, both through a micromechanical approach (Knudsen and Ochs 2018, Concha et al. 2018, Sarabia-Vallejos et al. 2019) or at the organ level (Berger et al. 2016, Roth et al. 2017, Avilés-Rojas and Hurtado xxx), and through multiphysics and multiscale approaches (Wall et al. 2010, Leonard-Duke et al. 2020). Several authors have demonstrated the need of using heterogeneous mechanical behavior for lung tissue modeling. One can refer for instance to Arora et al. (2021), Mariano et al. (2022), that performed ex-vivo 3D digital image correlation or digital volume correlation deformation measurements of inflated lungs at organ level. Thus, various constitutive laws have been considered for the parenchyma either or not based on microstructure or experimental measurements (Birzle and Wall 2019, Birzle et al. 2019). In this context, a lung biomechanical model was recently proposed in Patte et al. (2022) based on a general poromechanical formulation in large strains (Biot and Temple 1972, Chapelle et al. 2010, Chapelle and Moireau 2014). The model uses a two-phase mixture theory under the assumption of fluid incompressibility and isothermal conditions. The fluid phase represents air in the alveoli, while the solid phase represents tissues and blood, and is modeled with an hyperelastic free energy potential suitable for biological soft tissues such as lung parenchyma. The boundary conditions for breathing modeling, already detailed in Patte et al. (2022), are a negative pleural pressure applied on the external surface of the lungs and a frictionless bilateral contact with the thorax. The model is associated to a personalization pipeline, introduced in Patte et al. (2022), which allows to generate patient-specific models based on clinical images, and thus to obtain biomarkers combining the laws of physics and acquired data, opening the door for a better understanding, diagnosis and treatment of pulmonary fibrosis. The work presented in this paper focuses on improving the lung model personalization pipeline based on clinical data presented in Patte et al. (2022), for the estimation of patients regional lung compliances. Segmentation and meshing steps were improved and automated. The method relies on two 3DCT images for each patient, taken at end-exhalation and end-inhalation (breath holding), which are routinely acquired on patients diagnosed with pulmonary fibrosis, either IPF or post-COVID-19, at Avicenne APHP Hospital, Bobigny, France. Patient-specific information, such as lungs and thorax geometry, breathing kinematics, local porosity and fibrotic regions are extracted from the images. The image registration step, from which breathing kinematics is derived, was made more robust through a multi-level (rigid body, affine and full motion) decomposition. Then, regional lung compliances are estimated through an inverse problem. Since pleural pressure cannot be measured in clinical routine, a generic pleural pressure was used for all patients in Patte et al. (2022), leading in some cases to inconsistent estimation results. In this paper, we assess this major drawback by introducing a new parametrization based on the estimation of a personalized pleural pressure in addition to material parameters, allowing the use of fully patient-specific boundary conditions for the inverse problem. Results on IPF patients are compared to previous work (Patte et al. 2022), and results on post-COVID-19 are presented for the first time. Materials and methods Thoracic imaging The personalized poromechanical modeling tools presented in this paper are based on patient-specific clinical data such as lung geometry, lung porosity and breathing kinematics, which are obtained from clinical imaging. CT scans are usually used for interstitial lung diseases (Hartley et al. 1994, Washko et al. 2011) and are routinely performed for the diagnosis, classification and long-term followup at Avicenne APHP Hospital, Bobigny, France. Two high resolution 3DCT scans were performed on each patient, at end-exhalation and end-inhalation, in the supine position with the arms above the head and in breath-hold during image acquisition, following French guidelines (Cottin et al. 2014). Visual image analysis and classification were done by a radiologist. In this study, 3DCT scans of three IPF patients and one post-COVID-19 patient were selected. The CT parameters used for acquisition and reconstruction are given in Table 1. Patient data were retrospectively retrieved according to the French law on medical research and compiled as required by the Commission Nationale de l’Informatique et des Libertés (CNIL). The study not requiring an informed consent received authorization CLEA-2019-96 from the Comité Local d’éthique d’Avicenne (CLEA).Table 1 Acquisition and reconstruction CT parameters for each patient CT parameters Patients IPF1 IPF2 IPF3 COVID1 Manufacturer Siemens Siemens Siemens GE Model Somatom Somatom Somatom Revolution HD KVP 120 120 120 120 Convolution kernel I70f/4 I70f/4 I70f/4 LUNG Columns 512 512 512 611 Rows 512 512 512 611 Axial pixel spacing [mm] 0.66 0.7 0.68 0.6 Slice thickness [mm] 0.75 0.75 0.75 0.6 Recall on lung poromechanical modeling General modeling assumptions As a general reminder, poromechanical modeling is intended to capture the heterogeneous mechanical behavior of the lung at organ level due to the incorporation of microscopic information, such as local porosity. In this model, the lung parenchyma was considered as a two-phase poroelastic continuum. We used a general large strain mixture theory presented in Chapelle and Moireau (2014) and applied to lung modeling in Patte et al. (2022). The solid phase regroups lung interstitial tissue and blood, and the fluid phase corresponds to air present in airways and alveoli. Both solid and fluid phases were considered as incompressible under normal breathing conditions, so that lung volume change is due to added and removed fluid phase to the mixture, respectively, with inhalation and exhalation. Thus, the model relies on lung local porosity information in the reference configuration, representing the volume fraction of air. Moreover, the following additional hypotheses were made:The transformation is assumed to be isothermal. End-exhalation and end-inhalation states were considered at static equilibrium. Internal fluid pressure is homogeneous and equal to atmospheric pressure. The existence of an unknown unloaded configuration at equilibrium corresponding to a null pleural pressure. The end-exhalation pleural pressure was set to a normal value of -0.5 kPa. Poromechanical framework We define the following kinematic mapping between the reference configuration, denoted Ω0, and the deformed configuration, denoted ω:1 χ_:=Ω0→ωX_↦x_=χ_X_. The corresponding deformation gradient is2 F__(X_):=∇__χ_=1__+∇__U_, where the displacement field is3 U_(X_):=χ_(X_)-X_=x_X_-X_. The associated local volume change of the mixture is4 J:=detF__=Φs+Φf, with Φs and Φf, respectively, the solid and fluid contributions to the mixture volume change. Moreover, we have5 Φf=ϕf·JΦs=ϕs·J=1-ϕf·J, where ϕs and ϕf are, respectively, the solid and fluid volume fraction in the deformed configuration. Thus, we have, in the reference configuration Ω0, Φf0+Φs0=1, and, in the deformed configuration ω, ϕf+ϕs=1. We also introduce the right Cauchy-Green deformation tensor6 C__:=F__T·F__, and its first three invariants:7 I1:=trC__I2:=12trC__2-trC__2I3:=detC__=J2. The Green-Lagrange strain tensor is denoted by8 E__:=12C__-1__. In addition to these kinematics variables, another variable is needed to characterize the fluid transport within the mixture. Thus, we define the fluid mass change per unit reference mixture volume, denoted ρ¯f±. Using the fluid incompressibility assumption, we have:9 ρ¯f±=ρf0·Φf-Φf0, with ρf0 the reference fluid mass density. Poromechanical equilibrium laws The weak form of the balance of linear momentum in the current and reference configurations are, respectively:10 ∫ωσ__:ε__u_∗dω=Wextu_∗∀u_∗, and11 ∫Ω0Σ__:dU_E__·U_∗dΩ0=WextU_∗∀U_∗, where σ__ and Σ__ are the Cauchy and second Piola-Kirchhoff stress tensors. ε__u_∗ is the linearized strain tensor, dU_E__·U_∗ is the differential of the Green-Lagrange strain tensor and Wext is the virtual work of the external forces that will be detailed in Sect. 2.2.5. We also consider the local mixture equilibrium between the fluid pressure pf and the solid hydrostatic pressure ps (formally defined in the next paragraph) such that12 pf=ps. Poromechanical constitutive law Following the second principle of thermodynamics, the second Piola-Kirchhoff stress tensor derives from a Helmholtz free energy function of the mixture, denoted ψ¯, with respect to E. ψ¯ is decomposed additively into a solid part ψ¯s and a fluid part ψ¯f:13 ψ¯E__,ρ¯f±=ψ¯sE__,Φs+ψ¯fΦf. Thus,14 Σ__=∂ψ¯E__,ρ¯f±∂E__=∂ψ¯s∂E__-psJC__-1, where the solid hydrostatic pressure ps:=-∂ψ¯s∂Φs is related to the volume change. The free energy function associated with the solid mechanical behavior is decomposed following:15 ψ¯sE__,Φs=W¯skelE__+W¯bulkΦs where the first term W¯skel accounts for the solid structure behavior and the second term W¯bulk stems from the compressibility of the solid phase. According to Patte et al. (2022, 2022), the hyperelastic response of the lung tissues may then be represented using the following strain-energy functions:16 W¯skelE__=α¯eδJ2-1-2ln(J)-1+β¯1I1-3-2ln(J)+β¯2I2-3-4ln(J)W¯bulkΦs=κ¯ΦsΦs0-1-lnΦsΦs0, where α¯,β¯1,β¯2,δ are material parameters and κ¯ is the solid bulk modulus which should be large enough to ensure quasi-incompressibility of the solid part. These parameters θ¯ represent the effective behavior of the mixture, intrinsically taking into account the local reference porosity such that:17 θ¯=1-Φf0θ=Φs0θ∀θ¯∈{α¯,β¯1,β¯2,κ¯}. One can note that homogeneous material parameters weighted with the local reference porosity can produce highly heterogeneous effective poromechanical behavior, depending on the heterogeneity of the porosity field, which is needed for the lung parenchyma (Maghsoudi-Ganjeh et al. 2021). Lung model As presented in Patte et al. (2022), since the initial configuration at end-exhalation is not stress free, the first step is to compute an unloaded configuration corresponding to a null pleural pressure. This is an inverse problem in which the initial porosity corresponding to the loaded end-exhalation configuration, denoted γe, is known. The only initial boundary condition is an homogeneous negative pleural pressure ppl,e, set to -0.5 kPa on the whole lung surface, while rigid body motion are blocked. The two unknowns are the inverse displacement u_0 and the reference porosity Φf0. The weak form of the problem is:18 Findu_0,ϕf0such that∀u_∗,∫ωeσ__(u_0,ϕf0):ε__(u_∗)dω=-∫γeppl,en_·u_∗dγ∀x_,pf=-∂W¯bulk∂Φsu_0,ϕf0 where ϕf0=Φf0∘χ_0-1J-1 using the inverse mapping χ_0-1. The model boundary conditions and some poromechanical quantities are illustrated in Fig. 1, where we used the multiplicative decomposition of the global deformation gradient as follow:19 F__=F__b·F__0. Fig. 1 Schematic representation of the main poromechanical quantities and model boundary conditions. From left to right, unloaded configuration, initial end-exhalation configuration and loaded end-inhalation configuration After the resolution of the inverse problem, the pre-stressed end-exhalation configuration at equilibrium is fully known. The loading towards the end-inhalation configuration involves much more complex boundary conditions. In addition to the negative pleural pressure on the whole lung surface, a bilateral sliding contact with no friction and no separation, is set between the lung and the thorax surface. The problem is then described by the following system of equations:20 FindU_,Φfsuch that∀U_∗,∫Ω0∂W¯skel∂E__:dU_E__·U_∗dΩ0-∫Ω0pfJC__-1:dU_E__·U_∗dΩ0=-∫Γ0pplJF__-T·N0_·U_∗dΓ0∀X_,pf=-∂W¯bulk∂Φs Model personalization procedure Figure 2 illustrates the required patients data, i.e., clinical images and segmentation in green, and the fully automated pipeline for the personalized estimation of regional lung compliance in blue.Fig. 2 Schematic representation of the personalized lung modeling pipeline with the required clinical data in green and the automated computational pipeline in blue Images segmentation The 3DCT images at end-exhalation and end-inhalation are, respectively, denoted Ie and Ii. From these images, lungs and thorax geometries are segmented, where the thorax designates the volume composed of both lungs and the mediastinum. For each lung, an healthy and a diseased region are distinguished in the end-exhalation image Ie. The lung segmentation is performed using a U-Net convolutional neural network specialized in the texture classification of fibrotic lungs (Rennotte et al. 2020). A Dice loss function was selected for network training. The learning optimizer used a stochastic gradient with momentum and considered a learning rate which varied with time according to a triangular learning cycle schedule (Smith 2017; Ronneberger et al. 2015). The database used for training and testing the convolutional neural network model was collected at Avicenne Hospital, Bobigny, France. The database included 156 patients totaling 2266 axial images. Among them, 137 patients (2076 slices) are used for train and validation and 19 patients (190 slices) for test. The ground truth annotations were performed manually by an expert radiologist using an in-house software. The segmentation algorithm provides healthy and diseased lung regions, the latter differentiating between fibrosis, ground glass and emphysema patterns. For all our study cases, the segmentation results were validated by an expert radiologist. Based on the lung segmentation, the thorax region was computed as the convex-hull volume encompassing the lungs and the mediastinum, extended in the cranio-caudal direction down to the lung basis. Such task automation is an important improvement with respect to our previous work (Patte et al. 2022) where lung healthy/diseased regions and thorax volume were defined manually based on lung shape segmentation (Rennotte et al. 2020). Note that the diseased region includes all anomalies related to fibrosis such as scar tissues, ground-glass opacities, honeycombing, etc. (Fetita et al. 2016). Mesh generation The segmented image slices are combined into a 3D image using the Visualization Toolkit (VTK) (Schroeder et al. 2006) for both end-exhalation and end-inhalation states. From the 3D images, the left lung, right lung and thorax are separately meshed. In previous work (Patte et al. 2022), the healthy and diseased regions segmentation of each lung was a binary field projected onto the finite element mesh, which did not explicitly represent the healthy-diseased interface. One of the improvements introduced in this paper is the explicit meshing of the healthy and diseased regions interface, directly from the automatic segmentation introduced above, using the Computational Geometry Algorithms Library (CGAL) (Project 2022). The 3D mesh generation tool from CGAL allows the generation of an isotropic mesh composed of multiple components or subdomains, here the two lung regions, with a coherent mesh interface. Linear tetrahedron is used. Porosity projection The porosity field is then computed from the CT images, which measure the attenuation of X-rays in the tissue related to density. Thus, each image pixel is displayed according to the mean attenuation of the tissue formulated in the Hounsfield units (HU) scale. Assuming a linear variation of porosity with HU, the local porosity can be computed with the expression:21 ϕf(x_)=HU(x_)-HUtissueHUair-HUtissue, with HUtissue=0HU considering that biological tissues are mainly composed of water and HUair=-1000HU. The porosity field computed from the end-exhalation image is projected onto the corresponding finite element mesh, assuming a constant value on each element. This value is equal to the mean of pixel values for all pixels inside the element. Image registration From the meshes of lungs and thorax, new binary masks are created using VTK tools, respectively Ml,e and Ml,i from empty 3D images of dimensions corresponding to Ie and Ii. The displacement field of the thorax between end-exhalation and end-inhalation is computed using finite element-based image registration. The method is described in (Genet et al. 2018), and the code is freely available at https://gitlab.inria.fr/mgenet/dolfin_warp. In our case, the registration problem involves the end-exhalation thoracic mesh and the Ml,e and Ml,i thoracic binary masks. Since the image registration problem of shapes is ill-posed (Vishnevskiy et al. 2017), a very small hyperelastic regularization term is used to prevent convergence issues. Moreover, to improve the robustness of the registration, which is especially difficult as thorax displacements during breathing can be very large (several centimeters), we introduce here an multi-level registration algorithm: First a rigid body displacement field U_rb is computed. From U_rb as initial solution, an affine displacement field U_affine then is computed. Finally the thorax displacement finite element field U_thorax is computed using U_affine as initial solution. The external surface of the volumetric thoracic mesh is then extracted with the corresponding nodal displacements and converted into shell elements. Model parameters estimation Patient-specific mechanical parameters of the skeleton energy W¯skel are estimated using the above data. In this study we consider lungs with two regions, healthy and fibrotic tissues. Each region is defined as sets of elements with homogeneous material model properties. Two kinds of estimation are performed: Identification of the material parameters for both regions imposing a generic end-inhalation pleural pressure ppl,i as already presented in Patte et al. (2022). Identification of the diseased region material parameters Θ¯d and end-inhalation pleural pressure ppl,i imposing a generic healthy region material parameter Θ¯h. However, the estimation problem of four parameters with the small amount of data available is highly ill-posed. Consequently, only the main volumetric stiffness parameters Θ¯h/d=α¯h/d, are estimated and the others are set as presented in Table 2.Table 2 Model parameters used in simulations for imposed ppl,i and imposed α¯h estimations Parameters Imposed ppl,i Imposed α¯h Healthy Diseased Healthy Diseased α¯ [kPa] – – 0.0275 – β¯1 [kPa] 0.2 0.2 0.2 0.2 β¯2 [kPa] 0.4 0.4 0.4 0.4 δ [–] 0.5 0.5 0.5 0.5 pf [kPa] 0 0 ppl,e [kPa] -0.5 -0.5 ppl,i [kPa] -1.85 – The estimation problem is formulated as an optimization problem, in which the solution is the set of parameters minimizing a cost function f, characterizing the distance between the model and the data and defined in the next paragraph. The optimization process is solved using the stochastic derivative-free numerical optimization algorithm CMA-ES (Auger and Hansen 2005; Hansen 2016), which evaluates the direct problem multiple times with different sets of parameters. Thus, for each CMA-ES evaluation the direct problem consists in computing the stress-free reference configuration from the end-exhalation configuration and the loaded end-inhalation configuration from the reference configuration. The stress-free reference configuration is computed using the FEniCS library (Aln et al. 2015) to solve the inverse hyperelastic problem (18) (code is freely available at https://gitlab.inria.fr/mgenet/dolfin_mech), while the loaded configuration is computed solving (20) using the Abaqus/Standard finite-element solver (ABAQUS 2009). As detailed in Patte et al. (2022), the cost function used in the optimization process is additively composed of two terms. The first one characterizes the discrepancy between the end-exhalation and end-inhalation images after mapping with the model, while the second term characterizes the discrepancy between the measured (from the images) and predicted (from the model) lung shape changes. In the sum, the weights are chosen such that both terms have an equivalent order of magnitude in the optimal state. Regional compliance definition In order to quantify the regional softness of the lung tissues, independently from the constitutive behavior and the patient-specific lung geometry, we define a global compliance Ct0→t1 between two time points t0 and t1. It is defined as a volume change divided by a pressure change, such that:22 Ct0→t1=Vt1-Vt0ppl,t1-ppl,t0, where Vt0 and ppl,t0 are, respectively, the lung volume and pleural pressure at time point t0, and Vt1 and ppl,t1 are the lung volume and pleural pressure at time point t1. In order to define the compliance independently from the patient, we take Vt0=1.3 L and ppl,t0=-0.5 kPa for all patients, and compute Vt1 on a simple Rivlin cube simulation. Results In this section, we present results of the identification. As described in Sect. 2.3.5, two kinds of identification are performed based on clinical data: either by imposing a generic end-inhalation pleural pressure, or by imposing a generic healthy compliance. Results are given in Table 3. Parameters identification We first reproduced identifications performed in Patte et al. (2022) on patients IPF1, IPF2 and IPF3, with the improved and fully automated personalization pipeline. In these computations the end-inhalation pleural pressure is set to ppl,i=-1.85 kPa for all patients and regional material parameters α¯h and α¯d are estimated. Results are presented in Table 3 and are qualitatively consistent with the identification of Patte et al. (2022). In order to address some of the limitations of the previous estimation, especially reduce the sensitivity to the quality of the clinical data such as large variability in patients breath, we propose to no longer impose the end-inhalation pleural pressure, and instead impose the lung healthy region stiffness (α¯h=0.0275 kPa) for all patients (see Table 2). Results are presented in Table 3.Table 3 Comparison of the identified parameters for both kind of estimation, imposed ppl,i and imposed α¯h Patients Imposed ppl,i Imposed α¯h α¯h [kPa] α¯d [kPa] α¯d [kPa] ppl,i [kPa] IPF1 0.021 0.199 5.532 -3.405 IPF2 27.42 1.682 5.753 -0.925 IPF3 0.005 3.859 6.634 -6.727 COVID1 0.006 0.021 3.252 -2.082 Clinical analysis Regional compliance If global pulmonary compliance is a frequently used biomarker for clinicians that need to quantify impact and severity of pulmonary fibrosis, regional compliance as presented in this article is not yet used in clinical routine. The method used for the computation of the compliance is presented in Sect. 2.4. Results for both kinds of identification are shown in Fig. 3. Compliance of the healthy lung region is higher than that of the diseased region except for the patient IPF2. This specificity is likely due to the very small amount of breathing between end-exhalation and end-inhalation images, resulting in a very small change in lung volume (around 14% while usually above 70%). These results are consistent with the literature reporting higher stiffness of fibrotic tissues (Plantier et al. 2018; Knudsen and Ochs 2018; Kang et al. 2021). As a reminder, normal compliance under natural breathing usually range from 0.6 to 1 L/kPa (Shelledy and Peters 2019), which is also consistent with our results. The use of a non-patient specific pleural pressure systematically lead to estimate a lower compliance for the diseased region in comparison to the regional identification. Also, compliance estimation for patient IPF2 is more consistent since the small change in volume, due to clinical data, affects the value of the pleural pressure and no longer the stiffness of the lung tissues. Note that patient COVID1 presents for both type of identification a larger compliance for the diseased region that the IPF patients, which might indicate an earlier stage of the disease.Fig. 3 Regional compliances and pleural pressure for each patient for both estimations, with imposed ppl,i (left) and with imposed α¯h (right) Stress distribution The assumption of a vicious mechanical circle has been formulated in the literature (Liu et al. 2010, 2015; Wu et al. 2020). This assumption states that mechanics may play a role in the evolution of pulmonary fibrosis and can be summarized as follows: a lower compliance of the diseased tissues leads to unphysiological stress concentrations that activate the production of collagen fibers inducing more fibrosis.Fig. 4 Comparison of fluid fraction of the mixture (left) and the solid hydrostatic pressure [kPa] (right) in a sagittal slice of the lung for patient IPF1 in the case of a non-patient specific pleural pressure estimation (imposed ppl,i) Fig. 5 Comparison of fluid fraction of the mixture (left) and the solid hydrostatic pressure [kPa] (right) in a sagittal slice of the lung for patient IPF1 in the case of a patient specific pleural pressure estimation (imposed α¯h) Figures 4 and 5 illustrate the local porosity and hydrostatic pressure distribution in the lung at end-inhalation for patient IPF1, in the case of estimation ppl,i imposed and α¯h imposed, respectively. The two regions considered as healthy and diseased can be distinguished looking at the porosity field, with a much lower fluid volume fraction of the mixture in the diseased area. The results clearly show an heterogeneous hydrostatic pressure field across the interface of the two regions, with stress concentrations in fibrotic tissues near healthy tissues that seem to support the mechanical vicious circle assumption. Moreover, one can observe a much more heterogeneous porosity field in the lung looking at results from estimation imposing α¯h in comparison to estimation imposing ppl,i, with higher fluid volume fraction in the healthy region and lower in the diseased region. Thus, higher stress levels and stress concentrations across the interface can be observed in case of identification with imposed α¯h. Discussion Personalized lung poromechanical modeling could represent an important tool for the better understanding of some of the mechanisms involved in pulmonary fibrosis. The patient-specific modeling pipeline presented in this study uses routine clinical images and aims to provide regional lung compliance in an automated way so that it can be run on large patients database. It builds upon (Patte et al. 2022), and the main pipelines improvements are summarized below:The segmentation and meshing steps were automated, as described in Sect. 2.3.1. Healthy and diseased regions are now explicitly represented in the mesh, with a coherent mesh interface, instead of a projected binary field, as described in Sect. 2.3.2. The image registration step was made more robust through a multi-level (rigid body, affine and full motion) decomposition, as described in Sect. 2.3.4. The parameter estimation step was made more consistent with a new parametrization of the optimization problem based on the estimation of a personalized pleural pressure in addition to material parameters, as described in Sect. 2.3.5. The entire model personalization pipeline was automated. If global lung compliance is widely used by clinicians, regional lung compliance currently cannot be measured without the use of such tool. This additional personalized information about the patient could be helpful for further clinical decisions, quantify severity and evolution of the disease or evaluate the effectiveness of a treatment from a mechanical point of view. In this study, poromechanical model of the lung was applied to three patients suffering from IPF and one from post-COVID-19 pulmonary fibrosis. We obtained results that are consistent with the current state of understanding of the disease. The parameters estimation systematically led to a stiffer diseased region in comparison to the healthy region, expect for patient IPF2 in the case where both lung regions stiffness where identified imposing the end-inhalation pleural pressure. This result highlights the very high sensitivity of this estimation to the quality of clinical data, since it is caused by the very small amount of breathing between end-exhalation and end-inhalation images. Imposing the stiffness of the healthy region, while the stiffness of the diseased region and the pleural pressure are estimated, gave the more consistent results. Indeed, for patient IPF2 the small amount of breathing led to the identification of a low pleural pressure instead of low tissue compliance. Moreover, the patient specific pleural pressure estimation systematically led to lower compliance of the diseased region in comparison to the patient specific healthy region stiffness identification, as well as higher pleural pressure (except for patient IPF2). Compliance quantification should also be studied in relation to other clinical observations such as spirometry or carbon monoxide diffusing capacity and compared to reference values (Galetke et al. 2007). Another interest of the poromechanical model is the study of the stress field in the lung tissues. Indeed, our model could help better understand the role of mechanics in pulmonary abnormal remodeling due to fibrosis. The existence of stress concentration at the border of the fibrotic region tends to confirm the hypothesis of the role of a mechanical vicious circle in the course of the disease. Results obtained from estimations using a patient specific pleural pressure give more heterogeneous porosity and stress fields in the lung that would still enforce the previous hypothesis. However, the model still needs to be applied on more patients, and longitudinally, in order to establish conclusive observations. Thus, the pipeline automation presented in this study drastically reduces the need for manual intervention and offers the perspective to be used on large patients database of segmented lungs with healthy and diseased regions in further work. However, the computational cost is still high and the tool developed is complex to set up in an outsourcing context, such as in a radiology department. Thus, other methods are promising and should be explored. One can cite for instance methods of mechanical parameters identification based on full-field measurements and not requiring an actual resolution of the model (Avril et al. 2004, 2008), which could allow to compute regional lung compliances directly from finite element image registration without dealing with complex and still approximated boundary conditions. This reduction of modeling complexity would allow more robust and computationally efficient numerical simulations. The present study has several limitations, both at the modeling and estimation levels, that are discussed in the following paragraphs. First, we considered a two-phases continuum, solid and fluid, were the solid phase regroups tissues and blood and the fluid phase corresponds to air. It would be possible to model three phases, considering for instance an independent but non patient-specific phase for blood. However, this rather simple representation allows the use of a poromechanical framework at the organ scale, taking into account heterogeneous porosity from personalized clinical data and projected onto the finite element mesh. One of the direct implication is that the measured porosity is not exactly represented but averaged inside an element. Moreover, we make the underlying assumption that the mechanical properties of the solid part of the mixture is homogeneous within one region of the mesh. A possible improvement could be the use of multi-scale model explicitly modeling lung interstitial tissues and airways (Álvarez-Barrientos et al. 2021). Improving boundary conditions and loadings could also lead to more relevant model parameters estimation. Gravity, for instance, could be to taken into account, both on the tissue itself and the imposed pleural pressure. Indeed, effect of gravity on human lung deformation have been studied in for instance in Seyfi Noferest et al. (2018), and authors showed that gravitational effects are significant on lung deformation, especially in the top part of the lung that is far from the diaphragm, and tends to improve model accuracy. And in terms of boundary conditions, the modeling of organs in the mediastinum such as heart, vessels and trachea, constraining lungs displacements could improve the parameters estimation. Furthermore, our model currently only represents two breathing states, namely end-exhalation & end-inhalation, considered in static equilibrium, and could be extended to dynamics to take into account inertia and hysteresis effects. However, patient-specific modeling always requires some trade-off between the model and clinically available data, and current computed tomography scans are very limited in terms of time frames. But recent magnetic resonance imaging techniques have allowed truly 4D imaging of the breathing lung (Boucneau et al. 2020), which could, once coupled to a dynamical poromechanics model, lead to more physiological personalized models. Regarding the estimation pipeline itself, due to our personalized modeling approach – namely we do not use directly lung displacements that could be computed from image registration, but directly the images – the patients breathing kinematic is not perfectly reproduced in our modeling with the current boundary conditions, i.e., homogeneous pleural pressure and thorax displacement extracted from the images. As already mentioned, one solution would be to use identification methods that consider directly the full-field kinematics extracted from the images (Avril et al. 2004, 2008). In the current setting, as already noted in Patte et al. (2022), the breathing motion error (i.e., the distance between the motion predicted by the model and the one observed in the images), is better quantified when using a displacement-based cost function rather than an image-based cost function. We assumed the existence of two regions in the lungs, considered as healthy and diseased, with homogeneous material properties. Note that, as mentioned above, the actual mechanical behavior within each region is still heterogeneous due to the heterogeneous porosity field. These regions are segmented using a method described in Rennotte et al. (2020) and explicitly meshed. The addition of several regions corresponding to specific CT visual analysis could be studied such as presence of ground-glass opacities, reticulations, honeycombing, etc. However, the use of multiple regions would considerably increase the space of solutions of the inverse analysis process that may lead to non-uniqueness of the solution and increase the uncertainty of the quantification. Since inverse problems are often ill-posed, we have limited our estimation to two parameters for each patient. An interesting outlook could be to perform uncertainty quantification when dealing with this small amount of input data with intrinsic noise. An interesting approach, based on a Bayesian multi-fidelity Monte-Carlo framework, has been recently proposed in the literature Nitzler et al. (2022). Author contributions All authors conceptualized the problematic, objective & approach. CL made the technical developments and prepared the figures, under M.G.’s supervision. CL wrote the manuscript. MG reviewed and edited the manuscript. All authors reviewed the manuscript. Funding This study was supported by the French National Research Agency (ANR) under contracts numbers ANR-10-EQPX-37, ANR-19-CE45-0007 and ANR-20-COV4-0004. Data availability The motion tracking tool is freely available at https://gitlab.inria.fr/mgenet/dolfin_warp. The computational mechanics tool is freely available at https://gitlab.inria.fr/mgenet/dolfin_mech. The images are available upon request. Declarations Ethical approval Patient data were retrospectively retrieved according to the French law on medical research and compiled as required by the Commission Nationale de l’Informatique et des Libertés (CNIL). The study not requiring an informed consent received authorization CLEA-2019-96 from the Comité Local d’Éthique d’Avicenne (CLEA). Conflict of interest We declare no competing interests. Due to a revision to Table 2, the article's original online version was revised. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Change history 6/9/2023 A Correction to this paper has been published: 10.1007/s10237-023-01719-0 ==== Refs References ABAQUS/Standard user’s manual, Version 6.9. Dassault Systèmes Simulia Corp (2009) Aln MS, Kehlet B, Logg A, Richardson C, Ring J, Rognes E, Wells GN (2015) The FEniCS project version 1(5):15 Arora H Mitchell R Johnston R Manolesos M Howells D Sherwood J Bodey A Wanelik K Correlating local volumetric tissue strains with global lung mechanics measurements Materials 2021 14 2 439 10.3390/ma14020439 33477444 Auger A, Hansen N (2005) A restart CMA evolution strategy with increasing population size. In: 2005 IEEE congress on evolutionary computation, vol. 2, pp. 1769–1776. IEEE. 10.1109/CEC.2005.1554902 Avilés-Rojas N, Hurtado DE Whole-lung finite-element models for mechanical ventilation and respiratory research applications 14. 10.3389/fphys.2022.984286 Avril S Bonnet M Bretelle A-S Grédiac M Hild F Ienny P Latourte F Lemosse D Pagano S Pagnacco E Pierron F Overview of identification methods of mechanical parameters based on full-field measurements Exp Mech 2008 48 4 381 402 10.1007/s11340-008-9148-y Avril S Grédiac M Pierron F Sensitivity of the virtual fields method to noisy data Comput Mech 2004 34 6 439 452 10.1007/s00466-004-0589-6 Ballering AV, van Zon SKR, olde Hartman TC, Rosmalen JGM, (2022) Persistence of somatic symptoms after COVID-19 in the Netherlands: an observational cohort study. Lancet 400(10350):452–461. 10.1016/S0140-6736(22)01214-4 Berger L Bordas R Burrowes K Grau V Tavener S Kay D A poroelastic model coupled to a fluid network with applications in lung modelling: a poroelastic model coupled to a fluid network with applications in lung modelling Int J Numer Methods Biomed Eng 2016 10.1002/cnm.2731 Biot MA Temple G Theory of finite deformations of porous solids Indiana Univ Math J 1972 21 7 597 620 10.1512/iumj.1972.21.21048 Birzle AM Hobrack SMK Martin C Uhlig S Wall WA Constituent-specific material behavior of soft biological tissue: experimental quantification and numerical identification for lung parenchyma Biomech Model Mechanobiol 2019 18 5 1383 1400 10.1007/s10237-019-01151-3 31053928 Birzle AM Wall WA A viscoelastic nonlinear compressible material model of lung parenchyma - experiments and numerical identification J Mech Behav Biomed Mater 2019 94 164 175 10.1016/j.jmbbm.2019.02.024 30897504 Boucneau T Fernandez B Larson P Darrasse L Maître X 3D Magnetic resonance spirometry Sci Rep 2020 10 1 9649 10.1038/s41598-020-66202-7 32541799 Carloni A Poletti V Fermo L Bellomo N Chilosi M Heterogeneous distribution of mechanical stress in human lung: a mathematical approach to evaluate abnormal remodeling in IPF J Theor Biol 2013 332 136 140 10.1016/j.jtbi.2013.04.038 23665208 Chapelle D Gerbeau J-F Sainte-Marie J Vignon-Clementel IE A poroelastic model valid in large strains with applications to perfusion in cardiac modeling Comput Mech 2010 46 1 91 101 10.1007/s00466-009-0452-x Chapelle D Moireau P General coupling of porous flows and hyperelastic formulations-from thermodynamics principles to energy balance and compatible time schemes Eur J Mech B Fluids 2014 46 82 96 10.1016/j.euromechflu.2014.02.009 Concha F Sarabia-Vallejos M Hurtado DE Micromechanical model of lung parenchyma hyperelasticity J Mech Phys Solids 2018 112 126 144 10.1016/j.jmps.2017.11.021 Cottin V Crestani B Valeyre D Wallaert B Cadranel J Dalphin J-C Delaval P Israel-Biet D Kessler R Reynaud-Gaubert M Aguilaniu B Bouquillon B Carre P Danel C Faivre J-B Ferretti G Just N Kouzan S Lebargy F Marchand-Adam S Philippe B Prevot G Stach B Thivolet-Bejui F Cordier J-F The French national reference centre and the network of competence centres for rare lung diseases: diagnosis and management of idiopathic pulmonary fibrosis: French practical guidelines Eur Respir Rev 2014 23 132 193 214 10.1183/09059180.00001814 24881074 Fetita C, Tarando S, Brillet P-Y, Grenier PA (2016) Robust lung identification in MSCT via controlled flooding and shape constraints: dealing with anatomical and pathological specificity, p. 97881. 10.1117/12.2216687 Flaherty KR Fell CD Huggins JT Nunes H Sussman R Valenzuela C Petzinger U Stauffer JL Gilberg F Bengus M Wijsenbeek M Safety of nintedanib added to pirfenidone treatment for idiopathic pulmonary fibrosis Eur Respir J 2018 52 2 1800230 10.1183/13993003.00230-2018 29946005 Galetke W Feier C Muth T Ruehle K-H Borsch-Galetke E Randerath W Reference values for dynamic and static pulmonary compliance in men Respir Med 2007 101 8 1783 1789 10.1016/j.rmed.2007.02.015 17419042 Genet M Stoeck CT von Deuster C Lee LC Kozerke S Equilibrated warping: finite element image registration with finite strain equilibrium gap regularization Med Image Anal 2018 50 1 22 10.1016/j.media.2018.07.007 30173000 George PM Wells AU Jenkins RG Pulmonary fibrosis and COVID-19: the potential role for antifibrotic therapy Lancet Respir Med 2020 8 8 807 815 10.1016/S2213-2600(20)30225-3 32422178 Giacomelli C Piccarducci R Marchetti L Romei C Martini C Pulmonary fibrosis from molecular mechanisms to therapeutic interventions: lessons from post-COVID-19 patients Biochem Pharmacol 2021 193 114812 10.1016/j.bcp.2021.114812 34687672 Hansen N (2016) The CMA evolution strategy: A tutorial 1604.00772 [cs, stat] Hartley PG Galvin JR Hunninghake GW Merchant JA Yagla SJ Speakman SB Schwartz DA High-resolution CT-derived measures of lung density are valid indexes of interstitial lung disease J Appl Physiol 1994 76 1 271 277 10.1152/jappl.1994.76.1.271 8175517 Kang JH Choi J Chae KJ Shin KM Lee C-H Guo J Lin C-L Hoffman EA Lee C CT-derived 3D-diaphragm motion in emphysema and IPF compared to normal subjects Sci Rep 2021 11 1 14923 10.1038/s41598-021-93980-5 34290275 Knudsen L Ochs M The micromechanics of lung alveoli: structure and function of surfactant and tissue components Histochem Cell Biol 2018 150 6 661 676 10.1007/s00418-018-1747-9 30390118 Lee LC Genet M Dang AB Ge L Guccione JM Ratcliffe MB Applications of computational modeling in cardiac surgery J Card Surg 2014 29 3 293 302 10.1111/jocs.12332.29citations(Crossref)[2022-04-27] 24708036 Leonard-Duke J Evans S Hannan RT Barker TH Bates JHT Bonham CA Moore BB Kirschner DE Peirce SM Multi-scale models of lung fibrosis Matrix Biol 2020 91–92 35 50 10.1016/j.matbio.2020.04.003 Liu F Lagares D Choi KM Stopfer L Marinković A Vrbanac V Probst CK Hiemer SE Sisson TH Horowitz JC Rosas IO Fredenburgh LE Feghali-Bostwick C Varelas X Tager AM Tschumperlin DJ Mechanosignaling through YAP and TAZ drives fibroblast activation and fibrosis Am J Physiol-Lung Cell Mol Physiol 2015 308 4 344 357 10.1152/ajplung.00300.2014 Liu F Mih JD Shea BS Kho AT Sharif AS Tager AM Tschumperlin DJ Feedback amplification of fibrosis through matrix stiffening and COX-2 suppression J Cell Biol 2010 190 4 693 706 10.1083/jcb.201004082 20733059 Maghsoudi-Ganjeh M Mariano CA Sattari S Arora H Eskandari M Developing a lung model in the age of COVID-19: a digital image correlation and inverse finite element analysis framework Front Bioeng Biotechnol 2021 9 684778 10.3389/fbioe.2021.684778 34765590 Mariano CA Sattari S Quiros KAM Nelson TM Eskandari M Examining lung mechanical strains as influenced by breathing volumes and rates using experimental digital image correlation Respir Res 2022 23 1 92 10.1186/s12931-022-01999-7 35410291 McGroder CF Zhang D Choudhury MA Salvatore MM D’Souza BM Hoffman EA Wei Y Baldwin MR Garcia CK Pulmonary fibrosis 4 months after COVID-19 is associated with severity of illness and blood leucocyte telomere length Thorax 2021 76 12 1242 1245 10.1136/thoraxjnl-2021-217031 33927016 Michalski JE Kurche JS Schwartz DA From ARDS to pulmonary fibrosis: the next phase of the COVID-19 pandemic? Transl Res 2022 241 13 24 10.1016/j.trsl.2021.09.001 34547499 Morton SE Dickson J Chase JG Docherty P Desaive T Howe SL Shaw GM Tawhai M A virtual patient model for mechanical ventilation Comput Methods Programs Biomed 2018 165 77 87 10.1016/j.cmpb.2018.08.004 30337083 Neelakantan S Xin Y Gaver DP Cereda M Rizi R Smith BJ Avazmohammadi R Computational lung modelling in respiratory medicine J R Soc Interface 2022 19 191 20220062 10.1098/rsif.2022.0062 35673857 Nitzler J, Biehler J, Fehn N, Koutsourelakis P-S, Wall WA (2022) A generalized probabilistic learning approach for multi-fidelity uncertainty quantification in complex physical simulations. arXiv. http://arxiv.org/abs/2001.02892 Nunes H Schubel K Piver D Magois E Feuillet S Uzunhan Y Carton Z Tazi A Levy P Brillet P-Y Nicholson AG Kambouchner M Valeyre D Nonspecific interstitial pneumonia: survival is influenced by the underlying cause Eur Respir J 2015 45 3 746 755 10.1183/09031936.00148613 25537566 Patte C Brillet P-Y Fetita C Bernaudin J-F Gille T Nunes H Chapelle D Genet M Estimation of regional pulmonary compliance in idiopathic pulmonary fibrosis based on personalized lung poromechanical modeling J Biomech Eng 2022 144 9 091008 10.1115/1.4054106 35292805 Patte C Genet M Chapelle D A quasi-static poromechanical model of the lungs Biomech Model Mechanobiol 2022 21 2 527 551 10.1007/s10237-021-01547-0 35072891 Plantier L Cazes A Dinh-Xuan A-T Bancal C Marchand-Adam S Crestani B Physiology of the lung in idiopathic pulmonary fibrosis Eur Respir Rev 2018 27 147 170062 10.1183/16000617.0062-2017 29367408 Project TC (2022) CGAL User and reference manual, 5.5 ed edn. CGAL Editorial Board. https://doc.cgal.org/5.5/Manual/packages.html Rennotte S, Brillet P-Y, Fetita C (2020) Comparison of CNN architectures and training strategies for quantitative analysis of idiopathic interstitial pneumonia. In: Hahn HK, Mazurowski MA (eds.) Medical Imaging 2020: computer-aided diagnosis, vol. 11314, p. 113140. 10.1117/12.2548476 Ronneberger O, Fischer P, Brox T (2015) U-Net: convolutional networks for biomedical image segmentation. arXiv. http://arxiv.org/abs/1505.04597 Roth CJ Ismail M Yoshihara L Wall WA A comprehensive computational human lung model incorporating inter-acinar dependencies: application to spontaneous breathing and mechanical ventilation Int J Numer Method Biomed Eng 2017 33 1 02787 10.1002/cnm.2787 Sarabia-Vallejos MA Zuñiga M Hurtado DE The role of three-dimensionality and alveolar pressure in the distribution and amplification of alveolar stresses Sci Rep 2019 9 1 8783 10.1038/s41598-019-45343-4 31217511 Schroeder W, Martin K, Lorensen B (2006) The visualization toolkit: an object-oriented Approach to 3D graphics ; visualize data in 3D - medical, engineering or scientific ; build your own applications with C++, Tcl, Java or Python ; Includes source sode for VTK (supports Unix, Windows and Mac), 4. ed edn. Kitware, Inc Seyfi Noferest B Santhanam AP Ilegbusi OJ Effect of gravity on subject-specific human lung deformation Math Comput Model Dyn Syst 2018 24 1 87 101 10.1080/13873954.2017.1382537 Shelledy DC, Peters JI (2019) Mechanical Ventilation, pp. 449–526. Jones & Bartlett Learning Smith NP de Vecchi A McCormick M Nordsletten DA Camara O Frangi AF Delingette H Sermesant M Relan J Ayache N Krueger MW Schulze WHW Hose R Valverde I Beerbaum P Staicu C Siebes M Spaan J Hunter PJ Weese J Lehmann H Chapelle D Rezavi R EuHeart: personalized and integrated cardiac care using patient-specific cardiovascular modelling Interface focus 2011 1 3 349 64 10.1098/rsfs.2010.0048.00070 22670205 Smith LN (2017) Cyclical learning rates for training neural networks. arXiv. http://arxiv.org/abs/1506.01186 Vishnevskiy V Gass T Szekely G Tanner C Goksel O Isotropic total variation regularization of displacements in parametric image registration IEEE Trans Med Imaging 2017 36 2 385 395 10.1109/TMI.2016.2610583 27654322 Wall WA Wiechert L Comerford A Rausch S Towards a comprehensive computational model for the respiratory system Int J Numer Methods Biomed Eng 2010 10.1002/cnm.1378 Washko GR Hunninghake GM Fernandez IE Nishino M Okajima Y Yamashiro T Ross JC Estépar RSJ Lynch DA Brehm JM Andriole KP Diaz AA Khorasani R D’Aco K Sciurba FC Silverman EK Hatabu H Rosas IO Lung volumes and emphysema in smokers with interstitial lung abnormalities N Engl J Med 2011 364 10 897 906 10.1056/NEJMoa1007285 21388308 Wu H Yu Y Huang H Hu Y Fu S Wang Z Shi M Zhao X Yuan J Li J Yang X Bin E Wei D Zhang H Zhang J Yang C Cai T Dai H Chen J Tang N Progressive pulmonary fibrosis is caused by elevated mechanical tension on alveolar stem cells Cell 2020 180 1 107 12117 10.1016/j.cell.2019.11.027 31866069 Álvarez-Barrientos F Hurtado DE Genet M Pressure-driven micro-poro-mechanics: a variational framework for modeling the response of porous materials Int J Eng Sci 2021 169 103586 10.1016/j.ijengsci.2021.103586
PMC010xxxxxx/PMC10010224.txt	==== Front Wetlands (Wilmington) Wetlands (Wilmington) Wetlands (Wilmington, N.c.) 0277-5212 1943-6246 Springer Netherlands Dordrecht 36936606 1675 10.1007/s13157-023-01675-6 Wetland Ecology Invertebrate Richness and Hatching Decrease with Sediment Depth in Neotropical Intermittent Ponds http://orcid.org/0000-0002-6705-1916 de Oliveira Hoffmann¹ Pedro Henrique 1 http://orcid.org/0000-0001-5443-0055 Adolfo² Andressa 2 http://orcid.org/0000-0002-4911-9788 Piu² Allana Gonçalves 2 http://orcid.org/0000-0002-9851-3669 Vendramin² Daiane 2 http://orcid.org/0000-0002-0069-1601 Martins² Lidiane 2 http://orcid.org/0000-0003-4554-6413 Weber¹ Vinicius 1 http://orcid.org/0000-0002-5321-7524 Maltchik¹ Leonardo 1 http://orcid.org/0000-0002-9095-2018 Stenert Cristina [email protected] 1 1 grid.411598.0 0000 0000 8540 6536 Instituto de Ciências Biológicas, Programa de Pós-graduação em Biologia de Ambientes Aquáticos Continentais, Universidade Federal do Rio Grande – FURG, Avenida Itália, km 8, 96203-900 Rio Grande, RS Brazil 2 grid.412302.6 0000 0001 1882 7290 Universidade do Vale do Rio dos Sinos (UNISINOS), Av. Unisinos 950, São Leopoldo, Rio Grande do Sul Brazil 13 3 2023 2023 43 3 2429 7 2022 27 2 2023 © The Author(s), under exclusive licence to Society of Wetland Scientists 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Some groups of invertebrates from intermittent wetlands produce dormant stages in response to environmental fluctuations. Dormancy is a strategy to survive such fluctuations and to persist in extreme aquatic habitats, such as temporary habitats. We investigated the hatching responses of invertebrate dormant stages across different depths of sediment in intermittent ponds. Our hypotheses were: (1) the richness and abundance of invertebrate hatchlings decrease as the depth of the sediment column increases, and (2) the composition of invertebrate hatchlings varies over the wetland sediment depth. Four intermittent ponds were sampled in southern Brazil. One sediment column of 30 cm depth was collected in each pond and stratified into 1 cm thick slices for analysis of the dormant stages. A total of 1,931 hatchlings distributed among 31 taxa were collected from the sediment columns over the experiment. The total richness and abundance of hatchlings (after bdelloid taxa exclusion) were negatively related with the sediment depth. The composition of aquatic invertebrates varied among the different strata over the sediment depth. As intermittent wetlands are ecosystems extremely susceptible to climate variations, the results help to understand the resilience of aquatic resistant communities from different sediment strata after drought events. Supplementary Information The online version contains supplementary material available at 10.1007/s13157-023-01675-6. Keywords Dormant stages Invertebrate hatchlings Sediment column Temporary wetlands Viability http://dx.doi.org/10.13039/501100003593 Conselho Nacional de Desenvolvimento Científico e Tecnológico 474892/2013-1 issue-copyright-statement© Society of Wetland Scientists 2023 ==== Body pmcIntroduction Some groups of invertebrates from intermittent wetlands produce dormant stages in response to environmental fluctuations (Brendonck and De Meester 2003; Parra et al. 2021), such as resistant eggs and cysts (Williams 2006). Dormancy is a strategy to survive such fluctuations and to persist in extreme aquatic habitats (Santangelo 2009; Strachan et al. 2015; García-Roger et al. 2017). Several taxa of invertebrate use dormancy as a survival strategy, and wetland sediments may contain thousands of dormant stages of different species per square meter, particularly rotifers, cladocerans and copepods (Hairston 1996; Panarelli et al. 2008; Day et al. 2010; Brendonck et al. 2017). The production and hatching of invertebrate dormant stages in intermittent wetlands are influenced by several environmental variables. Frequency and length of hydroperiod are important variables to hatching patterns and production of invertebrate dormant stages (Nielsen et al. 2000; Vargas et al. 2019; da Silva Bandeira et al. 2020). Temperature and photoperiod are also key factors for invertebrate hatching patterns (Gyllström and Hansson 2004; Wang and Chou 2015). Water chemistry factors (e.g., salinity, conductivity and dissolved oxygen) are also important abiotic hatching cues (Brendonck 1996; Vanschoenwinkel et al. 2010). The bank of dormant stages of aquatic invertebrates is a historical ecological archive, formed by the overlap of several generations, which allows correlating the dynamics of communities to environmental changes (Brendonck and De Meester 2003; Rogalski 2015; Rogalski et al. 2017; García-Roger and Ortells 2018). For instance, the hatching of dormant stages of rotifers, cladocerans and copepods after decades of dormancy has been reported in sediments from the estuary of the Pettaquamscutt River in Rhode Island, USA (Marcus et al. 1994). There are examples of even older hatchings, such as copepods around 300 years old (Hairston et al. 1995), cladoceran genetic material dated to 600 years old (Frisch et al. 2014) and a bdelloid rotifer of 24,000 years dormant in the permafrost of the Alazeya River in Siberia, Russia (Shmakova et al. 2021). This feature can be used as an important ecological and evolutionary tool for studies of dormant aquatic invertebrate communities (Brendonck and De Meester 2003; Angeler 2007). Studies indicate that the upper layer of the sediment (between 4 and 10 cm) has the highest concentrations of viable dormant stages (Herzig 1985; Cáceres 1998; Cáceres and Hairston 1998; Hairston et al. 2000; Santangelo 2009). Therefore, the unhatched dormant stages accumulate at greater depths over time (Ellner and Hairston 1994; Brendonck and De Meester 2003), and the hatching rate tends to decrease with depth (Hairston et al. 1999; Kerfoot et al.1999). Nonetheless, studies correlating the viability of dormant stages and the depth of the sediment were carried out mainly in intermittent wetlands in temperate regions of Europe and North America (Herzig 1985; Hairston et al. 1995; Kerfoot et al.1999; Gyllström and Hansson 2004). This relationship was poorly studied in Neotropical region (Iglesias et al. 2016). The studies that report the presence of dormant stages in southern and southeastern Brazil wetlands (Maia-Barbosa et al. 2003; Stenert et al. 2010, 2016, 2017; Santangelo et al. 2014; Ávila et al. 2015; Freiry et al. 2016, 2020a, b; Vargas et al. 2019; Brazil et al. 2022) only analyzed the top layers of the sediment (3–5 cm). Here, we investigated the hatching responses of invertebrate dormant stages across different depths of sediment in intermittent ponds. The objectives were to: (1) evaluate the richness, abundance and composition of hatched invertebrates along a vertical gradient of the sediment column, and (2) compare the hatching of the main taxonomic groups along the sediment column. Our first hypothesis is that the richness and abundance of invertebrate hatchlings decrease as the depth of the sediment column increases since the largest fraction of viable and more responsive dormant stages occurs in the top layers of the sediment (Hairston et al. 2000; Brendonck and De Meester 2003; Yousey et al. 2018). Our second hypothesis is that the composition of invertebrate hatchlings varies over the wetland sediment depth considering that several invertebrate taxa use dormancy as a survival strategy (Brendonck et al. 2017) and that not all dormant stages have the same ability to survive for long in the egg bank (Hairston 1996). Materials and methods Study Area This study was conducted in the Coastal Plain of Southern Brazil, a region extending across approximately 640 km with a high concentration of wetlands (Maltchik et al. 2003) (Fig. 1). The climate is moist subtropical with a mean annual temperature of 17.5 ◦C, and the annual mean rainfall ranges from 1,200 to 1,500 mm (Rambo 2000). The flat topography of the landscape and the low altitudes (lower than 20 m) makes climate conditions very similar throughout the study region. Fig. 1 Location of the study region and of the four ponds (C1 – C4) studied in the southern Brazilian Coastal Plain Sampling Design Four intermittent depressional ponds were sampled in April 2019 (Fig. 1). The isolated ponds analyzed were intermittent, with similar sizes (1 ha) and water depth (0.5 m on average) distant at least 15 km from each other. On each pond, one sediment column of 30 cm depth was collected using a Russian peat borer (Modelo 2460-F20) (5-cm diameter). To collect the sediment, the tube corer was pushed vertically, avoiding disturbance in the deeper part of the sediments. The sediment sampling was carried out when the ponds had water. Each sediment column was transferred to a PVC corer adapted to receive the sediment column, without alteration. The samples were kept in darkness by wrapping in aluminum foil and refrigerated (4 ◦C) until experiments start (Cousyn and De Meester 1998; García-Roger and Ortells 2018). Data collection complied with the current Brazilian environmental laws (SISBIO 36365-2). Laboratory Procedures Each sediment column was stratified into 1 cm thick slices for analysis of the dormant stages. Since the upper centimeters of the sediment contains the active egg bank, the slice thickness varied with depth, with smallest intervals (1 cm) in the top layers (up to 6 cm) and 4 cm for deeper sediment layers (Hairston et al. 1995, 2000; Kerfoot et al. 1999; Brendonck and De Meester 2003). In total, eleven slices per sediment column (pond) were incubated in our experiment all in the same period (0-1 cm, 1–2 cm, 2–3 cm, 3–4 cm, 4–5 cm, 5–6 cm, 10–11 cm, 15–16 cm, 20–21 cm, 25–26 cm e 30–31 cm), totalizing 44 samples (11 samples x 4 selected ponds). All slices were dehydrated in a dark oven for 96 h at 40 °C. In the incubation experiment, each sediment slice was submersed under a depth of 2 cm of distilled water into plastic trays without aerators, and water temperature (23 ± 2 ºC) and photoperiod (12 h light/12 hours dark) were kept constant (Ávila et al. 2015; Stenert et al. 2010). The experiment was maintained in the laboratory for 4 weeks (June 7th to July 5th, 2019), and hatchlings were collected three times per week, corresponding to 12 sampling days, by filtering all the water content from each plastic tray through a 50-µm mesh size net. The collected hatchlings were transferred to 1.5-mL polypropylene microtubes with 80% alcohol or 4% formaldehyde (Rotifera) (Freiry et al. 2016). The distilled water was changed after each sampling day. The duration of the experiment (4 weeks) was based on previous work from our research group (Freiry et al. 2020b; Vendramin et al. 2020) and others (Brock et al. 2003). Hatchlings were quantified under stereomicroscope (Zeiss Stemi 2000) and identified to species level whenever possible using specialized literature (Koste 1978; Elmoor-Loureiro 1997; Gazulha 2012) and aid of specialists. Data Analyses The richness and abundance of aquatic invertebrates were the taxa number (number of species or genus – whenever possible – added to the number of taxa identified at lower taxonomic resolutions – phylum, class, or family level) and number of hatchlings, respectively. The relationship of invertebrate richness and abundance with different sediment depths was tested with generalized linear models (GLMs). As both response variables were discrete, GLMs were fitted with Poisson (richness) and negative binomial (abundance) distributions (because of major overdispersion of residuals) and log link function. The predictor variable (sediment depth) was included in the models as a numerical variable. The models were tested for richness and abundance of the total community. Each sediment column was divided into three different strata: superficial (from 1 to 5 cm, represented by five slices – 1, 2, 3, 4 and 5 cm), intermediate (from 6 to 20 cm, represented by three slices – 6, 11 and 16 cm) and deep (from 21 to 31 cm, represented by three slices – 21, 26 and 31 cm) to analyze the spatial variation in the composition of hatchlings. The spatial variation in the composition of aquatic invertebrates among the different depth strata was assessed using nonmetric multidimensional scaling ordination diagram (NMDS) and a nonparametric multivariate analysis of variance (PERMANOVA) with 9,999 permutations. The NMDS and PERMANOVA analyses were based on an incidence matrix (Jaccard index). A similarity percentage analysis (SIMPER; Clarke 1993; 999 permutations) was used to identify the taxa that mostly contributed to differences among depth strata. We used the PERMDISP approach (betadisper function) (Anderson 2006) to test for differences in the multivariate dispersion among the sediment depth strata. All statistical analyses were conducted with the functions from packages vegan, car, MASS, lme4 and ggplot2 in the R software v. 4.0.3 (R Development Core Team 2020). The Panplot2 portable software (Sieger and Grobe 2013) and CorelDRAW were used to visualize the total hatching percentage of the main invertebrate taxa in relation to sediment depth. Results A total of 1,931 hatchlings distributed among 31 taxa were collected from the sediment columns over the experiment. Phylum Rotifera comprised most of the hatchlings (82%), followed by the Phylum Gastrotricha (8%) and Phylum Annelida (Family Aeolosomatidae − 6%). The Subphylum Crustacea (2.5%) was represented by the Class Ostracoda (1.8%), Subclass Copepoda (only 1 nauplius – 0.05%) and Order Anomopoda (Cladocera, 13 individuals – 0.7%). Phylum Nematoda (1.2%), Phylum Tardigrada (0.4%) and Phylum Platyhelminthes (class Turbellaria – microturbellarians – 0.3%) corresponded to the rest of the hatched individuals. The most abundant taxa were the bdelloid rotifers Philodina sp. (52%) and Adineta sp. (12%), and the monogonont rotifers Lecane leontina Turner, 1892 (9%) and Ptygura pilula (7%) (Table 1). Although the highest percentage of hatchings of these taxa occurred in the surface layers of sediment, some individuals hatched at depths greater than 20 cm (Table 1; Fig. 2). Table 1 Total abundance of invertebrate hatchlings along the sediment depths of the studied ponds Taxonomic classification Depth strata (cm) Phylum Class Subclass Order Family Species 0–1 1–2 2–3 3–4 4–5 5–6 10–11 15–16 20–21 25–26 20–31 Annelida Polychaeta Aeolosomatidae 2 2 40 38 1 1 16 1 1 1 9 Arthropoda Brachiopoda Phyllopoda Anomopoda Chydoridae Chydorus eurynotus Sars, 1901 0 0 0 1 1 1 0 0 0 1 0 Leydigia sp. 0 0 1 0 0 3 0 0 0 0 0 Ilyocryptidae Ilyocryptus sordidus Liévin, 1848 0 0 0 0 1 0 0 0 0 0 0 Ilyocryptus spinifer Herrick, 1882 1 1 0 0 0 0 0 0 0 0 0 Macrothricidae Macrothrix sp. 0 0 2 0 0 0 0 0 0 0 0 Ostracoda 11 3 5 3 6 7 0 0 0 0 0 Copepoda 1 0 0 0 0 0 0 0 0 0 0 Gastrotricha 42 16 29 25 11 29 5 3 0 0 0 Platyhelminthes Turbellaria 3 0 0 0 2 0 1 0 0 0 0 Rotifera Eurotatoria Bdelloidea Adinetidae Adineta sp. 0 0 0 18 132 7 32 31 5 0 0 Philodinidae Philodina sp. 26 7 54 32 110 194 173 9 99 244 47 Monogononta Ploima Notommatidae Cephalodella sp. 2 1 6 1 2 2 0 0 0 0 0 Cephalodella gibba Ehrenberg, 1830 0 1 0 0 0 6 0 0 0 0 0 Monommata dentata Wulfert, 1940 8 0 0 0 0 0 0 0 0 0 0 Notommata sp. 0 0 0 0 0 0 0 1 0 0 0 Euchlanidae Dipleuchlanis propatula Gosse, 1886 1 1 0 0 0 0 0 0 0 0 0 Epiphanidae Epiphanes brachionus Ehrenberg, 1837 0 0 0 0 0 0 0 6 0 0 0 Lecanidae Lecane sp. 2 0 0 0 0 0 0 0 0 0 0 Lecane bulla Gosse, 1851 0 0 0 4 0 0 0 0 0 0 0 Lecane leontina Turner, 1892 164 1 2 0 1 0 0 0 0 0 0 Lepadellidae Lepadella sp. 0 0 0 0 0 0 1 0 0 0 0 Brachionidae Platyias quadricornis Ehrenberg, 1832 1 0 0 0 0 0 0 0 0 0 0 Trichocercidae Trichocerca sp. 2 0 0 0 0 0 0 0 0 0 0 Trichocerca elongata Gosse, 1886 0 0 0 0 0 1 0 0 0 0 0 Trichocerca flagellata Hauer, 1937 3 0 0 0 0 0 0 0 0 0 0 Flosculariaceae Flosculariidae Ptygura pilula Cubitt, 1872 16 6 7 14 60 24 0 0 0 0 0 Floscularia sp. 0 1 0 1 1 0 0 0 0 0 0 Testudinellidae Testudinella patina Hermann, 1783 0 0 0 0 2 3 0 0 0 0 0 Nematoda 3 0 13 5 0 0 0 0 1 1 0 Tardigrada 4 2 0 0 1 0 0 0 0 0 0 Fig. 2 Percentage of hatchings of aquatic invertebrates along the sediment depths over the experiment The total richness of taxa was negatively influenced by the sediment depth, since the hatchings showed greater richness in the top layers compared to the deeper ones (Z = -5.533; p < 0.001; Fig. 3). The total hatching abundance was not influenced by depth (Z = -1.197; p = 0.231) (Fig. 4). Considering that the dominance of the Bdelloidea rotifers could influence variation in abundance, we excluded these taxa and reanalyzed the data. After bdelloid taxa exclusion, the abundance was also negatively influenced by the sediment depth (Z = -5.460; p < 0.001) (Fig. 5). Fig. 3 Total richness of aquatic invertebrates along the sediment depths of the studied ponds Fig. 4 Total abundance of aquatic invertebrates along the sediment depths of the studied ponds Fig. 5 Abundance of aquatic invertebrates after bdelloid taxa exclusion (see main text for details) along the sediment depths of the studied ponds The composition of aquatic invertebrates varied among the different strata over the sediment depth (PERMANOVA, F2,41 = 3.022; p < 0.001) and this variation was displayed by two axes of the NMDS diagram (stress = 0.125) (Fig. 6). The PERMANOVA results were not affected by multivariate dispersion within the sediment depth strata (F2,41 = 0.846; p = 0.446). The similarity percentage (SIMPER) analysis revealed that nine taxa significantly contributed to the dissimilarity in the composition of the different strata, and the taxa with the highest contribution were Adineta sp., Ptygura pilula, Ostracoda, Gastrotricha and Aeolosomatidae (Online Resource 1). Fig. 6 Nonmetric multidimensional scaling ordination for aquatic invertebrate hatchlings from superficial, intermediate and deep strata along the sediment of the studied ponds. The red crosses (+) are the invertebrate taxa; the filled black dots (●) corresponded to the superficial stratum; the filled gray dots (●) corresponded to the intermediate stratum; and the unfilled black dots (○) corresponded to the deep stratum Discussion Our hypothesis that the total richness and abundance (after exclusion of bdelloid rotifers) of invertebrate hatchlings decrease with sediment depth was supported in this study. Similarly, a range of studies on other wetland systems report greater abundance of hatchlings in the top layer of the sediment for several taxa, including Ostracoda, Cladocera and Copepoda, but mostly for rotifers (Carvalho and Wolf 1989; De Stasio 1990; Hairston et al. 1995; Ning and Nielsen 2011). Our results are in line with the idea that the surface layers of the sediment have the highest concentrations of viable dormant stages, responding better to hatching stimuli (Cáceres 1998; Cáceres and Hairston 1998; Hairston et al. 2000; Santangelo 2009). Another plausible explanation for hatching pattern observed may be related to the temporal degradation of the dormant eggs at deeper sediment depths that leads to higher mortality due to senescence, disease, and parasitism (Hairston et al. 1995, 2000; Kerfoot et al. 1999; Brendonck and De Meester 2003). Although it was not possible to date the sediment in our study, the positive relationship between the depth at which the invertebrate dormant stages are found in the sediment and their age is well known in undisturbed aquatic systems (Brendonck and De Meester 2003; Kerfoot and Weider 2004). Studies that report the presence of dormant stages in southern Brazil wetlands only analyzed the top layers of the sediment (Palazzo et al. 2008; Ávila et al. 2015; Freiry et al. 2016; Stenert et al. 2016, 2017). This study evaluated the hatching of dormant stages of aquatic invertebrates across different depths of sediment (from top to deeper layers) in intermittent ponds, showing that most hatchings were from the Phylum Rotifera, Phylum Gatrotricha and Phylum Annelida. Some studies that evaluated only the top layers of the sediment in intermittent ponds of the same region (Freiry et al. 2020a, b; Vendramin et al. 2020, 2022) showed that the crustaceans from the Order Anomopoda (cladoceran species) were the most representative in the hatched invertebrate community. In our study, the hatchlings of the cladoceran species were also mainly related to the top layers of the sediment (5–6 cm). The bdelloid rotifers represented by Adineta sp. and Philodina sp. comprised 64% of the total abundance found in this study. The high dominance of these two genera may be related to two factors: quick response from its dormant stages to environmental cues and asexual reproduction within 24 h. Rotifers of the Subclass Bdelloidea are known for their parthenogenesis and their dormant stage (anhydrobiosis), which allow them to withstand severe periods of desiccation (Ricci 2001). The physiological mechanisms that allow bdelloid rotifers to survive dehydrated during dormancy involve the protection of molecules such as sugars, proteins, and antioxidants (Rebecchi 2013), and the ability to recover their DNA when rehydrated (Hespeels et al. 2014). When water returns to the system, dormancy is broken, and within 24 h the individuals can reproduce by parthenogenesis (Ricci 2001). In this sense, although the sampling intervals of 2–3 days were used to minimize the chance of parthenogenetic reproduction (Brock et al. 2005; Nielsen et al. 2013), we cannot assume that all individuals of Bdelloidea found in this study are hatchlings from dormant stages. In our experiment, taxa such as Aeolosomatidae, Nematoda and Gastrotricha hatched at depths greater than 20 cm. These taxa have specific dormancy characteristics, sheltering in the sediment until they finish the metabolic processes related to the dormant stages (Poinar Jr 2010; Strayer et al. 2010; Alekseev and Pinel-Alloul 2019; Fontaneto 2019). Aeolosomatidae can form desiccation-resistant cysts (hardened membrane of mucus secreted by the worm) that allow them to survive adverse environmental conditions (Glasby et al. 2021). Gastrotrichs produce resting eggs that are thick-shelled and very resistant to freezing and drying (Strayer et al. 2010). These organisms generally occur in the upper 5 cm of the sediment, but depending on environmental conditions, they may occur at greater depths (Ricci and Balsamo 2000). Nematodes can coil, losing most of their internal water and halting their metabolic activity, remaining in this dormant condition until water becomes available again (Rebecchi et al. 2007). There is evidence that the survival of adult dormant nematodes can be extremely long, reaching over 30 years (McSorley 2003). Our result showed the presence of dormant stages capable of hatching in sediments up to 30 cm deep in intermittent wetlands. In ecological terms, this information is important, even if the stimuli necessary for hatching are reduced in deeper sediments. Dormant stages of deeper sediments can reach the surface through the stirring of the sediment by animals. Fish, insects, worms and wetland molluscs can commonly disturb sediments (Brendonck and De Meester 2003). Intermittent ponds are often visited by different species that, when interacting with the environment, can disturb the sediment and expose the dormant stages to the surface, such as watering cattle, birds and other large mammals (Brendonck and De Meester 2003). The reduction of dormant stages along the sediment depth of wetlands also is important in terms of conservation and restoration. The existence of dormant stages in the deepest parts of the sediment can be fundamental for the resilience of aquatic invertebrates when the dormant forms of the surface sediment are compromised with environmental impact. A greater richness and abundance of invertebrate hatchlings were observed in the top layers of sediment (up to 10 cm). Our results demonstrate that the hatching rate of invertebrates decreases with depth in sediments from temporary wetlands. These results help to understand the dormancy breaking strategies of aquatic invertebrates that produce dormant stages in temporary wetlands, and they are important to understand the recovery capacity of dormant community from different sediment strata after drought events. As intermittent wetlands are extremely susceptible to climate variations, the results help to show the resilience of drought resistant communities in the face of unstable hydrological dynamics of these ecosystems. Electronic Supplementary Material Below is the link to the electronic supplementary material. Supplementary Material 1 Acknowledgements We thank Gerson Fauth, Simone Fauth and Guilherme Krahl for their scientific support and the sample equipment. Author Contributions Pedro Henrique de Oliveira Hoffmann, Cristina Stenert and Leonardo Maltchik contributed to the study conception, design and writing – first draft, review and editing. Field and laboratory work were performed by Allana Gonçalves Piu, Lidiane Martins, Vinicius Weber and Daiane Vendramin. Data analysis were performed by Cristina Stenert, Pedro Henrique de Oliveira Hoffmann and Andressa Adolfo. Funding acquisition, project administration and supervision were peformed by Cristina Stenert and Leonardo Maltchik. All authors read and approved the final manuscript. Data availability The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request. Code Availability Not applicable. Declarations Statements and Declarations Funding. This research was supported by CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico (Grant number 474892/2013-1). CNPq granted IC scholarships to PHOH, AGP, LM, VW. CAPES supported DV with a doctoral fellowship. LM and CS hold Research Productivity Grants from CNPq. Conflict of interest/Competing Interests The authors declare no conflict of interest regarding this publication. The authors have no relevant financial or non-financial interests to disclose. Ethics Approval We declare that data collection complied with the current Brazilian environmental laws (SISBIO 36365-2). Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Alekseev VR Pinel-Alloul B Dormancy in aquatic organisms. Theory, human use and modeling 2019 Cham Springer Anderson MJ Distance-based tests for homogeneity of multivariate dispersions Biometrics 2006 62 245 253 10.1111/j.1541-0420.2005.00440.x 16542252 Angeler DG (2007) Resurrection ecology and global climate change research in freshwater ecosystems. J North Am Benthol Soc 26:12–22. 10.1899/0887-3593(2007)26[12:REAGCC]2.0.CO;2 Ávila AC Boelter T Santos RM Stenert C Würdig NL Rocha O Maltchik L The effects of different rice cultivation systems and ages on resting stages of wetland invertebrates in southern Brazil Mar Freshw Res 2015 66 276 285 10.1071/MF14048 Brazil T Caetano ACL Vargas AL Bozelli RL Santangelo JM Desiccation increases the hatching of resting eggs of a freshwater calanoid copepod J Plankton Res 2022 44 273 277 10.1093/plankt/fbac008 Brendonck L Diapause, quiescence, hatching requirements: what we can learn from large freshwater branchiopods (Crustacea: Branchiopoda: Anostraca, Notostraca, Conchostraca) Hydrobiologia 1996 320 85 97 10.1007/BF00016809 Brendonck L De Meester L Egg banks in freshwater zooplankton: evolutionary and ecological archives in the sediment Hydrobiologia 2003 491 65 84 10.1023/A:1024454905119 Brendonck L Pinceel T Ortells R Dormancy and dispersal as mediators of zooplankton population and community dynamics along a hydrological disturbance gradient in inland temporary pools Hydrobiologia 2017 796 201 222 10.1007/s10750-016-3006-1 Brock MA Nielsen DL Shiel RJ Green JD Langley JD Drought and aquatic community resilience: the role of eggs and seeds in sediments of temporary wetlands Freshw Biol 2003 48 1207 1218 10.1046/j.1365-2427.2003.01083.x Brock MA Nielsen DL Crosslé K Changes in biotic communities developing from freshwater wetland sediments under experimental salinity and water regimes Freshw Biol 2005 50 1376 1390 10.1111/j.1365-2427.2005.01408.x Cáceres CE Interspecific variation in the abundance, production, and emergence of Daphnia diapausing eggs Ecology 1998 79 1699 1710 10.2307/176789 Cáceres CE Hairston NG Benthic-pelagic coupling in planktonic crustaceans: the role of the benthos Arch Hydrobiol 1998 52 163 174 Carvalho GR Wolf HG Resting eggs of lake- Daphnia I. distribution, abundance and hatching of eggs collected from various depths in lake sediments Freshw Biol 1989 22 459 470 10.1111/j.1365-2427.1989.tb01118.x Clarke KR Non-parametric multivariate analyses of changes in community structure Austral Ecol 1993 18 117 143 10.1111/j.1442-9993.1993.tb00438.x Cousyn C De Meester L The vertical profile of resting egg banks in natural populations of the pond-dwelling cladoceran Daphnia magna Arch Hydrobiol 1998 52 127 139 da Silva Bandeira MG Martins KP Palma-Silva C Hepp LU Albertoni EF Hydration time influences microcrustacean hatching in intermittent wetlands: in situ and ex situ approaches Hydrobiologia 2020 847 3227 3245 10.1007/s10750-020-04315-w Day J, Day E, Ross-Gillespie V, Ketley A (2010) The assessment of temporary wetlands during dry conditions.Water Research Commission Report TT434/09, Water Research Commission. https://www.wrc.org.za/wpcontent/uploads/mdocs/TT&2043409%20Conservation%20of%20Water%20Ecosystems.pdf De Stasio BT Jr The role of dormancy and emergence patterns in the dynamics of a freshwater zooplankton community Limnol Oceanogr 1990 35 1079 1090 10.4319/lo.1990.35.5.1079 Ellner S Hairston NG Jr Role of overlapping generations in maintaining genetic variation in a fluctuating environment Am Nat 1994 143 403 417 10.1086/285610 Elmoor-Loureiro LMA Manual de identificação de cladóceros límnicos do Brasil 1997 Brasília Universa, Universidade Católica de Brasília Fontaneto D Long-distance passive dispersal in microscopic aquatic animals Mov Ecol 2019 7 1 10 10.1186/s40462-019-0155-7 30693085 Freiry RF Esquinatti FM Stenert C Arenzon A Nielsen DL Maltchik L Effects of spatial scale and habitat on the diversity of diapausing wetland invertebrates Aquat Biol 2016 25 173 181 10.3354/ab00666 Freiry RF Weber V Bonecker CC Lansac-Tôha FA Pires MM Stenert C Maltchik L Additive partitioning of the diversity of the dormant zooplankton communities in intermittent ponds along a forest–grassland transition Hydrobiologia 2020 847 1327 1342 10.1007/s10750-020-04187-0 Freiry RF Gouvea A Becker J Lansac-Tôha FA Lansac-Tôha FM Pires MM Stenert C Maltchik L Community structure and concordance patterns among zooplankton life stages in subtropical temporary ponds Aquat Ecol 2020 54 257 270 10.1007/s10452-019-09740-1 Frisch D Morton PK Chowdhury PR Culver BW Colbourne JK Weider LJ Jeyasingh PD A millennial-scale chronicle of evolutionary responses to cultural eutrophication in Daphnia Ecol Lett 2014 17 360 368 10.1111/ele.12237 24400978 García-Roger EM Carmona MJ Serra M Modes, mechanisms and evidence of bet hedging in rotifer diapause traits Hydrobiologia 2017 796 223 233 10.1007/s10750-016-2869-5 García-Roger EM Ortells R Trade-offs in rotifer diapausing egg traits: survival, hatching, and lipid content Hydrobiologia 2018 805 339 350 10.1007/s10750-017-3317-x Gazulha V Zooplâncton límnico: manual ilustrado 2012 Rio de Janeiro Technical Books Glasby CJ Erséus C Martin P Annelids in extreme aquatic environments: diversity, adaptations and evolution Diversity 2021 13 98 10.3390/d13020098 Gyllström M Hansson LA Dormancy in freshwater zooplankton: induction, termination and the importance of benthic-pelagic coupling Aquat Sci 2004 66 274 295 10.1007/s00027-004-0712-y Hairston NG Jr Zooplankton egg banks as biotic reservoirs in changing environments Limnol Oceanogr 1996 41 1087 1092 10.4319/lo.1996.41.5.1087 Hairston NG Jr Vanbrunt RA Kearns CM Engstrom DR Age and survivorship of diapausing eggs in a sediment egg bank Ecology 1995 76 1706 1711 10.2307/1940704 Hairston NG Jr Perry LJ Bohonak AJ Fellows MQ Kearns CM Engstrom DR Population biology of a failed invasion: paleolimnology of Daphnia exilis in upstate New York Limnol Oceanogr 1999 44 477 486 10.4319/lo.1999.44.3.0477 Hairston NG Jr Hansen AM Schaffner WR The effect of diapause emergence on the seasonal dynamics of a zooplankton assemblage Freshw Biol 2000 45 133 145 10.1046/j.1365-2427.2000.00386.x Herzig A Resting eggs – a significant stage in the life cycle of crustaceans Leptodora kindti and Bythotrephes longimanus Verh Int Ver Theor Angew Limnol 1985 22 3088 3098 10.1080/03680770.1983.11897838 Hespeels B Knapen M Hanot-Mambres D Heuskin AC Pineux F Lucas S Koszul R Van Doninck K Gateway to genetic exchange? DNA double-strand breaks in the bdelloid rotifer Adineta vaga submitted to desiccation J Evol Biol 2014 27 1334 1345 10.1111/jeb.12326 25105197 Iglesias C Bonecker C Brandão L Crispim MC Eskinazi-Sant’Anna EM Gerhard M Portinho JL Maia-Barbosa P Panarelli E Santangelo JM Current knowledge of South American cladoceran diapause: a brief review Int Rev Hydrobiol 2016 101 91 104 10.1002/iroh.201501825 Kerfoot WC Robbins JA Weider LJ A new approach to historical reconstruction: combining descriptive and experimental paleolimnology Limnol Oceanogr 1999 44 1232 1247 10.4319/lo.1999.44.5.1232 Kerfoot WC Weider LJ Experimental paleoecology (resurrection ecology): chasing Van Valen’s Red Queen hypothesis Limnol Oceanogr 2004 49 1300 1316 10.4319/lo.2004.49.4_part_2.1300 Koste W Rotatoria 1978 Stuttgart Gebrüder Bosntraeget Maia-Barbosa PM Eskinazi-Sant’Anna EM Valadares CF Pessoa GCD The resting eggs of zooplankton from a tropical, eutrophic reservoir (Pampulha Reservoir, south-east Brazil) Lakes Reserv Res Manag 2003 8 269 275 10.1111/j.1440-1770.2003.00229.x Maltchik L Costa ES Becker CG Oliveira AE Inventory of wetlands of Rio Grande do sul (Brazil) Pesq Bot 2003 53 89 100 Marcus NH Lutz R Burnettt W Cable P Age, viability, and vertical distribution of zzoplankton resting eggs from and anoxic basin: evidence of an egg bank Limnol Oceanog 1994 39 154 158 10.4319/lo.1994.39.1.0154 McSorley R Adaptations of nematodes to environmental extremes Fla Ent 2003 86 138 142 10.1653/0015-4040(2003)086[0138:AONTEE]2.0.CO;2 Nielsen DL Smith FJ Hillman TJ Shiel RJ Impact of water regime and fish predation on zooplankton resting egg production and emergence J Plankton Res 2000 22 433 446 10.1093/plankt/22.3.433 Nielsen DL Podnar K Watts RJ Wilson AL Empirical evidence linking increased hydrologic stability with decreased biotic diversity within wetlands Hydrobiologia 2013 708 81 96 10.1007/s10750-011-0989-5 Ning NSP Nielsen DL Community structure and composition of microfaunal egg bank assemblages in riverine and floodplain sediments Hydrobiologia 2011 661 211 221 10.1007/s10750-010-0525-z Palazzo F Bonecker CC Nagae MY Zooplankton dormancy forms in two environments of the upper Paraná River floodplain (Brazil) Acta Limnol Bras 2008 20 55 62 Panarelli EA Casanova SMC Henry R The role of resting eggs in the recovery of zooplankton community in a marginal lake of the Paranapanema River (São Paulo, Brazil), after a long drought period Acta Limnol Bras 2008 20 73 88 Parra G Guerrero F Armengol J Brendock L Brucet S Finlayson CM Gomes-Barbosa L Grillas P Jeppesen E Ortega F Vega R Zohary T The future of temporary wetlands in drylands under global change Inland Waters 2021 11 445 456 10.1080/20442041.2021.1936865 Poinar GO Jr Thorp JH Covich AP Nematoda and Nematomorpha Ecology and classification of freshwater invertebrates of North America 2010 3 San Diego Academic Press 237 276 R Development Core Team R: a language and environment for statistical computing 2020 Vienna R Foundation for Statistical Computing Rambo B A Fisionomia do Rio Grande do sul 2000 São Leopoldo, Brazil Unisinos Rebecchi L Dry up and survive: the role of antioxidant defences in anhydrobiotic organisms J Limnol 2013 72 62 72 10.4081/jlimnol.2013.s1.e8 Rebecchi L Altiero T Guidetti R Anhydrobiosis: the extreme limit of desiccation tolerance Invert Surv J 2007 4 65 81 Ricci C Dormancy patterns in rotifers Hydrobiologia 2001 446 1 11 10.1023/A:1017548418201 Ricci C Balsamo M The biology and ecology of lotic rotifers and gastrotrichs Freshw Biol 2000 44 15 28 10.1046/j.1365-2427.2000.00584.x Rogalski MA Tainted resurrection: metal pollution is linked with reduced hatching and high juvenile mortality in Daphnia egg banks Ecology 2015 96 1166 1173 10.1890/14-1663.1 26236831 Rogalski MA Leavitt PR Skelly DK Daphniid zooplankton assemblage shifts in response to eutrophication and metal contamination during the Anthropocene Proc R Soc B 2017 284 1471 2954 10.1098/rspb.2017.0865 Santangelo JM Produção, eclosão e implicações ecológicas e evolutivas dos estágios dormentes do zooplâncton. Limnotemas 2009 Rio de Janeiro Sociedade Brasileira de Limnologia Santangelo JM Esteves FA Manca M Bozelli RL Disturbances due to increased salinity and the resilience of zooplankton communities: the potential role of the resting egg bank Hydrobiologia 2014 722 103 113 10.1007/s10750-013-1683-6 Shmakova L Malavin S Iakovenko N Vishnivetskaya T Shain D Plewka M Rivkina E A living bdelloid rotifer from 24,000-year-old Arctic permafrost Curr Biol 2021 31 R712 R713 10.1016/j.cub.2021.04.077 34102116 Sieger R, Grobe H (2013) Panplot 2: software to visualize profiles and time series. Helmholtz Centre for Polar and Marine Research, Bremerhaven, PANGAEA. Alfred Wegner Institute. 10.1594/PANGAEA.816201 Stenert C Bacca RC Ávila AC Maltchik L Rocha O Do hydrologic regimes used in rice fields compromise the viability of resting stages of aquatic invertebrates? Wetlands 2010 30 989 996 10.1007/s13157-010-0083-1 Stenert C Ehlert B Ávila AC Sousa FDR Esquinatti FM Batzer DP Maltchik L Dormant propagule banks of aquatic invertebrates in ponds invaded by exotic pine species in southern Brazil Mar Freshw Res 2016 68 954 963 10.1071/MF16067 Stenert C Wüsth R Pires MM Freiry RF Nielsen D Maltchik L Composition of cladoceran dormant stages in intermittent ponds with different hydroperiod lengths Ecol Res 2017 32 921 930 10.1007/s11284-017-1498-4 Strachan SR Chester ET Robson BJ Freshwater invertebrate life history strategies for surviving desiccation Springer Sci Rev 2015 3 57 75 10.1007/s40362-015-0031-9 Strayer DL Hummon WD Hochberg R Thorp JH Covich AP Gastrotricha Ecology and classification of freshwater invertebrates of North America 2010 3 San Diego Academic Press 163 172 Vanschoenwinkel B Seaman M Brendonck L Hatching phenology, life history and egg bank size of fairy shrimp Branchipodopsis spp. (Branchiopoda, Crustacea) in relation to the ephemerality of their rock pool habitat Aquat Ecol 2010 44 771 780 10.1007/s10452-010-9315-y Vargas AL Santangelo JM Bozelli RL Recovery from drought: viability and hatching patterns of hydrated and desiccated zooplankton resting eggs Internat Rev Hydrobiol 2019 104 26 33 10.1002/iroh.201801977 Vendramin D Klagenberg CS Provensi MR Stenert C Pires MM Medeiros ESF Reichard M Maltchik L Effects of the presence of annual killifish on the assemblage structure of resting stages of aquatic invertebrates in temporary ponds Limnetica 2020 39 1 16 10.23818/limn.39.01 Vendramin D Pires MM Freiry RF Schneider AEB Martins L Medeiros ESF Rocha O Stenert C Maltchik L Hatching dynamics of invertebrate dormant stages in temporary ponds are influenced by multiple hydrations Freshw Sci 2022 41 143 152 10.1092/23F2-2XBW-252B-DU5C Wang CC Chou LS Terminating dormancy: hatching phenology of sympatric large branchiopods in Siangtian Pond, a temporary wetland in Taiwan J Crustac Biol 2015 35 301 308 10.1163/1937240X-00002322 Williams DD The biology of temporary waters 2006 New York Oxford University Press Yousey AM Chowdhury PR Biddinger N Shaw JH Jeyasing PD Weider LJ Resurrected ‘ancient’ Daphnia genotypes show reduced thermal stress tolerance compared to modern descendants R Soc Open Sci 2018 5 2054 5703 10.1098/rsos.172193
PMC010xxxxxx/PMC10013232.txt	==== Front Soc Psychiatry Psychiatr Epidemiol Soc Psychiatry Psychiatr Epidemiol Social Psychiatry and Psychiatric Epidemiology 0933-7954 1433-9285 Springer Berlin Heidelberg Berlin/Heidelberg 36917277 2453 10.1007/s00127-023-02453-9 Original Paper Patterns and predictors of depressive and anxiety symptoms within a population-based sample of adults diagnosed with COVID-19 in Michigan http://orcid.org/0000-0001-7586-643X Titus Andrea R. [email protected] 1 Mezuk Briana 2 Hirschtick Jana L. 2 McKane Patricia 3 Elliott Michael R. 45 Fleischer Nancy L. 2 1 grid.137628.9 0000 0004 1936 8753 Department of Population Health, NYU Grossman School of Medicine, 180 Madison Avenue, New York, NY 10016 USA 2 grid.214458.e 0000000086837370 Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI USA 3 grid.467944.c 0000 0004 0433 8295 Lifecourse Epidemiology and Genomics Division, Michigan Department of Health and Human Services, Lansing, MI USA 4 grid.214458.e 0000000086837370 Department of Biostatistics, School of Public Health, University of Michigan, Ann Arbor, MI USA 5 grid.214458.e 0000000086837370 Survey Research Center, Institute for Social Research, University of Michigan, Ann Arbor, MI USA 14 3 2023 2023 58 7 10991108 14 2 2022 27 2 2023 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Purpose The COVID-19 pandemic has had wide-ranging impacts on mental health, however, less is known about predictors of mental health outcomes among adults who have experienced a COVID-19 diagnosis. We examined the intersection of demographic, economic, and illness-related predictors of depressive and anxiety symptoms within a population-based sample of adults diagnosed with COVID-19 in the U.S. state of Michigan early in the pandemic. Methods Data were from a population-based survey of Michigan adults who experienced a COVID-19 diagnosis prior to August 1, 2020 (N = 1087). We used weighted prevalence estimates and multinomial logistic regression to examine associations between mental health outcomes (depressive symptoms, anxiety symptoms, and comorbid depressive/anxiety symptoms) and demographic characteristics, pandemic-associated changes in accessing basic needs (accessing food/clean water and paying important bills), self-reported COVID-19 symptom severity, and symptom duration. Results Relative risks for experiencing poor mental health outcomes varied by sex, age, race/ethnicity, and income. In adjusted models, experiencing a change in accessing basic needs associated with the pandemic was associated with higher relative risks for anxiety and comorbid anxiety/depressive symptoms. Worse COVID-19 symptom severity was associated with a higher burden of comorbid depressive/anxiety symptoms. “Long COVID” (symptom duration greater than 60 days) was associated with all outcomes. Conclusion Adults diagnosed with COVID-19 may face overlapping risk factors for poor mental health outcomes, including pandemic-associated disruptions to household and economic wellbeing, as well as factors related to COVID-19 symptom severity and duration. An integrated approach to treating depressive/anxiety symptoms among COVID-19 survivors is warranted. Supplementary Information The online version contains supplementary material available at 10.1007/s00127-023-02453-9. Keywords COVID-19 Depression Anxiety Mental health Epidemiology http://dx.doi.org/10.13039/100009931 Michigan Department of Health and Human Services Michigan Public Health InstituteUniversity of Michigan Institute for Data ScienceRogel Cancer Center, University of MichiganDepartment of Epidemiology, University of Michiganhttp://dx.doi.org/10.13039/100000133 Agency for Healthcare Research and Quality T32HS026120 issue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction The COVID-19 pandemic has had far-reaching impacts on mental health [1, 2]. Within the general population, the pandemic has been found to be associated with symptoms of anxiety, depression, stress, sleep problems, substance use, and suicidal ideation [3–7]. However, fewer studies have examined mental health outcomes among adults diagnosed with COVID-19. The relationship between mental health and COVID-19 illness is multi-faceted: individuals with neuropsychiatric disorders (e.g., autism and related developmental disorders, schizophrenia and other forms of severe mental illness) may be at increased risk for COVID-19 infection and severe illness for a variety of reasons, including higher smoking rates or residential instability, which may impact ability to mitigate exposure risk [8, 9]. In addition, individuals who are diagnosed with COVID-19 face a potential multitude of psychological and functional challenges, including pandemic-associated disruptions to economic wellbeing, as well as acute symptoms, and the potential for neurological and psychiatric sequelae [10–14]. Emerging evidence also suggests that long-term effects of COVID-19 infections among some individuals, or “long COVID,” may manifest in both somatic and mental health symptoms [15–18]. Existing estimates of the burden of mental health disorders among individuals diagnosed with COVID-19 vary widely [19] but tend to suggest high risk of poor mental health outcomes within this population. A meta-analysis based on patient populations in China, Italy, Ecuador, Turkey, and Iran estimated that the prevalence of current depressive symptoms among patients diagnosed with COVID-19 was 45%, and the pooled prevalence of current anxiety symptoms was 47% [19]. Pooled estimates were based primarily on studies that used a range of self-rated questionnaires (e.g., Patient Health Questionnaire depression module-9). In addition, a more recent review estimated that over 30% of patients hospitalized with COVID-19 experienced persistent cognitive impairment, depression, and anxiety, potentially weeks to months following diagnosis [20]. Within the U.S., an analysis of electronic health record (EHR) data found that 33.6% of adults diagnosed with COVID-19 had a recorded neurological or psychiatric disorder within 6 months following diagnosis [21]. Among an internet-based convenience sample of U.S. adults with COVID-19 surveyed an average of 2.7 months following initial symptom onset, 52.4% had symptoms consistent with current major depressive disorder, assessed using the PHQ-9 [22]. Risk of poor mental health outcomes also varies by both demographic and clinical factors. In the U.S. population generally, pandemic notwithstanding, symptoms of depression and anxiety are more common among younger ages, among women, and among adults with existing medical morbidity [23, 24]. Consistent with this general population distribution, evidence to date suggests that depressive symptoms associated with COVID-19 are more common among younger individuals and individuals with greater symptom severity; however, one study found that depressive symptoms were more common among men than women [22]. Other studies have also reported that symptom severity and stigma associated with COVID-19 illness may be predictive of worse mental health outcomes [11, 25, 26]. While literature on mental health among individuals diagnosed with COVID-19 is growing, most existing studies focus on hospitalized patients, who represent a subset of individuals with particularly severe manifestations of the illness, and who may differ from non-hospitalized individuals in terms of age, comorbidities, and other risk factors [27, 28]. Examining depressive and anxiety symptoms only among hospitalized patients also precludes opportunities to comprehensively examine the role of illness severity in producing differential patterns of mental health outcomes. In this study, we explored the prevalence of anxiety, depressive, and comorbid depressive/anxiety symptoms within a representative sample of all adults diagnosed with COVID-19 in the U.S. state of Michigan prior to August 1, 2020—an early phase of the pandemic in which Michigan experienced a high volume of COVID-19 cases and deaths [29]. Using detailed questionnaire data, we also examined several predictors of depressive and anxiety symptoms, including sociodemographic characteristics, pandemic-associated economic factors (e.g., experiencing a change in access to food, clean water, and other basic needs), and illness-specific factors (e.g., somatic symptom severity and symptom duration). As our primary research question, we sought to identify which of these factors were independently associated with mental health outcomes among individuals diagnosed with COVID-19, highlighting potential opportunities for targeted interventions to address depressive and anxiety symptoms within this population. Methods Sample We used data from the Michigan COVID-19 Recovery Surveillance Study (MI CReSS), a representative survey of adults in Michigan who have experienced a COVID-19 diagnosis. MI CReSS is led by the University of Michigan and the Michigan Department of Health and Human Services. The sampling frame for this study included non-institutionalized Michigan adults (ages 18+) with a recorded positive COVID-19 PCR test in the Michigan Disease Surveillance System (MDSS). Respondents had to be alive at the time of the survey and able to complete the MI CReSS questionnaire either online or over the phone with a trained interviewer in English, Spanish, or Arabic. Adults missing a phone number, or who were missing either zip code or county information in the MDSS, were excluded from the sampling frame. Individuals were sampled based on timing of illness, as well as geographic strata, which included six public health emergency preparedness regions [30], the counties of Macomb, St. Clair, Washtenaw, Oakland, Monroe, Wayne (excluding the city of Detroit), and the city of Detroit. Timing of illness was based on self-reported symptom onset (if available), the collection date for the first positive COVID-19 test (if available), or, finally, the referral date to MDSS. Three sampling waves were included in this study and encompassed illness onset/test collection/referral dates prior to August 1, 2020. For all three waves, a “base” number of 50–70 individuals was drawn from each geographic region, while the remainder of the sample was drawn proportionally, based on overall case counts within each area. We excluded respondents with missing covariate or outcome information, with the exception of missing household income information, which was imputed using a hot-deck imputation process. Briefly, we employed the weighted sequential hot-deck (WSHD) method [31] and hot-deck propensity score (HDPS) imputation [32] to impute the income variable under the missing at random assumption. The result was a two-step procedure in which the income imputation is after the auxiliary variables imputation. Auxiliary variables included health status, primary insurance, citizenship, education level, marriage status, employment status, and race/ethnicity, which were imputed univariately using the WSHD method in a sequential order where prior imputed variables were used as predictor variables for subsequent imputations. Income was then imputed using the HDPS approach with 1–1 nearest neighbor matching. The imputation model controlled for respondents’ age, sex, and other pre-imputed demographic variables including race, education, marital status, employment status, health status, and citizenship, as well as sampling weights. Weighting was conducted in SAS 9.4 and Stata SE, version 17. Of the 1212 total respondents in the first 3 MI CReSS waves, 106 were missing outcome or covariate information (aside from household income), including 38 who were missing information on depressive or anxiety symptoms. An additional 19 proxy respondents were also excluded from the analysis. The remaining analytic sample for this study included 1087 respondents. The sample was weighted to the age and sex distribution of the sampling frame within each geographic stratum, and to the geographic distribution of cases in the population. The median time from onset/test collection/referral to survey completion was 20 weeks (IQR = 16–24 weeks), and the response rate was 31.8% (American Association for Public Opinion Research response rate #6) [33]. This secondary analysis of study data was reviewed by the University of Michigan Institutional Review Board and deemed exempt. Outcome measures We assessed current depressive symptoms based on responses to the Patient Health Questionnaire two-item survey (PHQ-2), which asks respondents over the last 2 weeks, “how often have you been bothered by having little interest or pleasure in doing things?” and “how often have you been bothered by feeling down, depressed or hopeless?” [34] Presence of current anxiety symptoms was assessed used the two-item Generalized Anxiety Disorder survey (GAD-2), which asks respondents over the last two weeks, “how often have you been bothered by feeling nervous, anxious or on edge?” and “how often have you been bothered by not being able to stop or control worrying?” [35] Responses to each item were measured using a four-point Likert scale, with options including “Never,” “For several days”, “For more than half the days”, and “Nearly every day.” Responses were assigned numerical values ranging from 0 (“Never”) to 3 (“Nearly every day”) and these values were summed within each 2-item construct. In line with prior literature, a cut-off score of 3 + was used to indicate the presence of depressive symptoms or anxiety symptoms [34]. Using these thresholds, we created a four-level variable indexing: (1) no anxiety or depressive symptoms (reference group), (2) depressive symptoms only, (3) anxiety symptoms only, and (4) comorbid depressive and anxiety symptoms. Predictor variables We examined associations between mental health and a range of predictors including sociodemographic characteristics and aspects of the pandemic and COVID-19 infection. Sociodemographic predictors included sex at birth (male, female); age (18–34, 35–54, 55–64, 65+); race/ethnicity (non-Hispanic White, non-Hispanic Black, Hispanic, non-Hispanic adults of another race/ethnicity, including multiracial); and past-year annual household income (< $35K, $35K–$74,999, $75K +). We included an indicator variable representing whether the respondent reported any pre-existing chronic disease (excluding a psychological or psychiatric condition), and an indicator variable representing a pre-existing psychological or psychiatric condition. These variables were derived from a question which asked respondents about pre-existing health conditions they had before being diagnosed with COVID-19 (“Have you ever been told by a doctor or other health professional that you have had any of the following conditions?”). Response options included emphysema or COPD, asthma, diabetes, heart disease or other cardiovascular disease, high blood pressure, liver disease, kidney disease, stroke or other cerebrovascular disease, cancer, immunosuppressive condition, autoimmune condition, physical disability, psychological/psychiatric condition, or any other condition. We included a single binary predictor variable indicating whether the respondent reported a change in accessing at least one basic need during the pandemic, based on the question, “Since the COVID-19 pandemic began, what has changed for you and your family?”, with the following response options: “You or your family were unable to get enough food or healthy food,” “You or your family were unable to access clean water,” and “You or your family were unable to pay important bills like mortgage, rent, or utilities.” Finally, we examined factors related to COVID-19 illness, including self-reported symptom severity (mild/asymptomatic, moderate, severe, very severe), and a binary variable representing whether the respondent reported somatic symptom duration consistent with “Long COVID” [36], which we defined as self-reported symptoms lasting at least 60 days [37]. All adjusted models also adjusted for survey type (phone versus online) and survey wave. Statistical analysis We first estimated the prevalence of depressive symptoms, anxiety symptoms, and comorbid depressive/anxiety symptoms within the sample as a whole and across categories of predictor variables. We then conducted a multinomial logistic regression analysis to estimate bivariate and adjusted relative risk ratio associations [38] between predictor variables and the four-level outcome variable. For adjusted models, we included all sociodemographic variables, as well as pandemic- and illness-associated variables that we hypothesized could be associated with mental health outcomes. Results from these models provide insight into the extent to which pandemic- and illness-related factors independently predict mental health symptoms, after accounting for differences in sociodemographic characteristics. Finally, we conducted a post hoc sensitivity analysis to examine the potential impact of using imputed income information on our results by re-estimating adjusted models excluding individuals with missing income data. All statistical analyses were conducted using Stata v. 17 and incorporated sampling strata parameters and survey weights for both point and variance estimation. Results Descriptive characteristics Descriptive statistics for the analytic sample are included in Table 1. The majority of the sample was female (56.1%) and non-Hispanic White (52.1%). Since the pandemic began, 26.6% reported experiencing a change in accessing at least one basic need. Over 50% of the analytic sample reported that their COVID-19 symptoms were “severe” or “very severe,” and 31.1% reported symptoms that lasted at least 60 days (i.e., Long COVID). Approximately one in four respondents were currently experiencing depressive or anxiety symptoms, with 6.7% reporting depressive symptoms only, 8.0% reporting anxiety symptoms only, and 11.6% reporting both.Table 1 Descriptive characteristics of MI CReSS analytic sample (N = 1087) Variable N Weighted % Sex Male 439 43.9 Female 648 56.1 Age category 18–34 268 26.4 35–44 175 17.5 45–54 232 22.4 55–64 231 20.1 65 + 181 13.6 Race/ethnicity Non-Hispanic White 659 52.1 Non-Hispanic Black 213 24.6 Hispanic 107 11.4 Another race/ethnicity 108 12.0 Income < $35 K 349 33.4 $35-$74,999 329 29.2 > $75 K 409 37.4 Any pre-existing condition (excluding psychiatric) 639 56.6 Prior psychiatric condition 126 11.3 Experienced change in access to basic needsa 273 26.6 Self-reported symptom severity Mild/asymptomatic 252 23.4 Moderate 283 24.7 Severe 324 30.5 Very severe 228 21.4 Long COVIDb 346 31.1 No depressive or anxiety symptoms 805 73.7 Depressive symptoms only 68 6.7 Anxiety symptoms only 93 8.0 Depressive and anxiety symptoms 121 11.6 aDefined as inability to access enough food or healthy food, inability to access clean water, or inability to pay important bills (including rent and utilities) bSelf-reported symptom length of at least 60 days Table 2 includes prevalence estimates for mental health outcomes across all predictor variables. Just over 30% of females reported depressive and/or anxiety symptoms, compared to just over 20% of males. Respondents with lower household incomes were more likely to report any symptoms compared to respondents with higher household incomes, and younger respondents were more likely to report anxiety symptoms, or combined depressive and anxiety symptoms, compared to older respondents. Approximately 40% of respondents reporting a change in access to basic needs, “very severe” COVID-19 symptoms, or Long COVID reported depressive and/or anxiety symptoms.Table 2 Weighted prevalence of depressive symptoms only, anxiety symptoms only, and combined depressive and anxiety symptoms across predictor variables. MI CReSS. N = 1087 No depressive or anxiety symptoms (%) Depressive symptoms only (%) Anxiety symptoms only (%) Combined depressive & anxiety symptoms (%) Sex Female 69.3 6.0 10.8 13.9 Male 79.2 7.6 4.5 8.6 Age 18–34 71.1 3.3 13.2 12.4 35–44 72.1 2.7 9.3 15.8 45–54 66.9 12.0 7.4 13.7 55–64 77.8 9.0 5.0 8.2 65 + 85.7 6.3 2.0 6.0 Race/ethnicity Non-Hispanic White 74.6 4.8 7.9 12.7 Non-Hispanic Black 72.2 7.3 9.3 11.3 Hispanic 69.7 14.5 8.0 7.8 Another race/ethnicity 76.4 6.4 6.1 11.1 Income < $35K 64.2 8.9 10.6 16.3 $35K–$74,999 75.9 6.1 7.5 10.5 $75K + 80.3 5.2 6.2 8.2 Any pre-existing condition (excluding psychiatric) Yes 70.5 8.8 6.6 14.0 No 77.8 3.9 9.9 8.4 Prior psychiatric condition Yes 39.6 12.2 14.6 33.6 No 78.0 6.0 7.2 8.8 Experienced change in access to basic needsa Yes 58.1 10.4 12.9 18.6 No 79.3 5.4 6.3 9.0 Symptom severity Mild/asymptomatic 83.2 3.5 6.1 7.1 Moderate 74.8 5.7 8.6 10.9 Severe 72.9 7.9 8.1 11.2 Very Severe 63.1 9.6 9.5 17.8 Long COVIDb Yes 61.0 11.2 10.4 17.5 No 79.4 4.7 7.0 8.9 aDefined as inability to access enough food or healthy food, inability to access clean water, or inability to pay important bills (including rent and utilities) bSelf-reported symptom length of at least 60 days Regression modeling results Table 3 includes results from bivariate and adjusted multinomial logistic regression models. In both bivariate and adjusted models, demographic patterns of depressive and anxiety symptoms largely reflected descriptive patterns observed in Table 2. In adjusted models, females had higher relative risks (RRs) of experiencing anxiety symptoms (adjusted relative risk ratio (aRRR) = 2.37, 95% confidence interval (CI) = 1.28, 4.38), compared to males, and age was inversely associated with poor mental health outcomes. Respondents ages 18–54 had a higher RR of anxiety symptoms (aRRR for 18–34 = 14.06, 95% CI = 3.58, 55.20; aRRR for 35–44 = 7.88; 95% CI = 1.93, 32.21; aRRR for 45–54 = 6.99, 95% CI = 1.76, 27.86) and a higher RR of comorbid depressive/anxiety symptoms (aRRR for 18–34 = 3.95, 95% CI = 1.62, 9.65; aRRR for 35–44 = 4.37, 95% CI = 1.77, 10.77; aRRR for 45–54 = 3.73, 95% CI = 1.52, 9.15), compared to respondents ages 65 + . Respondents of age 45–54 also had a higher RR of reporting depressive symptoms only, compared to individuals ages 65 + (aRRR = 2.86, 95% CI = 1.22, 6.71). Race/ethnicity was generally not associated with mental health outcomes, with the exception that Hispanic respondents had higher RRs of depressive symptoms compared to non-Hispanic White respondents (aRRR = 2.81, 95% CI = 1.19, 6.67). Respondents with annual household income less than $35,000 had higher RRs of experiencing combined depressive/anxiety symptoms (aRRR = 2.18, 95% CI = 1.17, 4.09), compared to respondents with higher income levels. Reporting a pre-existing condition (excluding psychological/psychiatric conditions) was associated with combined depressive/anxiety symptoms (aRRR = 1.84; 95% CI = 1.09, 3.11), while reporting a prior psychiatric condition was strongly associated with all levels of the outcome variable.Table 3 Relative risk ratios for depressive symptoms only, anxiety symptoms only and combined depressive and anxiety symptoms associated with predictor variables, from bivariate and adjusted multinomial logistic regression models, with “no depressive or anxiety symptoms” as the baseline category. MI CReSS. N = 1087a,b Depressive symptoms only Anxiety symptoms only Combined depressive and anxiety symptoms Bivariate Adjusted Bivariate Adjusted Bivariate Adjusted Sex (Male ref.) Female 0.90 (0.52, 1.55) 0.84 (0.47, 1.49) 2.71 (1.56, 4.71) 2.37 (1.28, 4.38) 1.83 (1.16, 2.90) 1.49 (0.91, 2.43) Age (65 + ref.) 18–34 0.64 (0.21, 1.91) 1.01 (0.32, 3.17) 8.08 (2.43, 26.94) 14.06 (3.58, 55.20) 2.48 (1.18, 5.25) 3.95 (1.62, 9.65) 35–44 0.52 (0.14, 1.90) 0.59 (0.16, 2.15) 5.64 (1.58, 20.16) 7.88 (1.93, 32.21) 3.13 (1.44, 6.78) 4.37 (1.77, 10.77) 45–54 2.45 (1.03, 5.82) 2.86 (1.22, 6.71) 4.82 (1.37, 16.87) 6.99 (1.76, 27.86) 2.91 (1.35, 6.31) 3.73 (1.52, 9.15) 55–64 1.57 (0.64, 3.85) 1.54 (0.64, 3.71) 2.83 (0.76, 10.51) 3.11 (0.78, 12.34) 1.51 (0.67, 3.39) 1.65 (0.67, 4.09) Race/ethnicity (Non-Hispanic White ref.) Non-Hispanic Black 1.56 (0.78, 3.12) 1.15 (0.54, 2.47) 1.22 (0.68, 2.17) 0.90 (0.46, 1.74) 0.92 (0.54, 1.55) 0.88 (0.47, 1.67) Hispanic 3.24 (1.57, 6.69) 2.81 (1.19, 6.67) 1.08 (0.47, 2.47) 0.53 (0.18, 1.51) 0.66 (0.29, 1.48) 0.51 (0.22, 1.21) Another race/ethnicity 1.31 (0.50, 3.38) 1.13 (0.41, 3.10) 0.76 (0.32, 1.79) 0.43 (0.17, 1.09) 0.85 (0.42, 1.75) 0.73 (0.34, 1.58) Income ($75 K + ref.) < $35 K 2.12 (1.12, 4.04) 1.39 (0.67, 2.88) 2.13 (1.17, 3.86) 1.72 (0.87, 3.42) 2.48 (1.49, 4.11) 2.18 (1.17, 4.09) $35 K–$74,999 1.22 (0.59, 2.53) 1.00 (0.46, 2.17) 1.28 (0.68, 2.41) 1.08 (0.54, 2.18) 1.36 (0.78, 2.37) 1.24 (0.67, 2.29) Any pre-existing condition, excluding psychiatric (None ref.) Yes 2.47 (1.32, 4.62) 1.70 (0.77, 3.76) 0.74 (0.46, 1.21) 0.84 (0.46, 1.53) 1.84 (1.19, 2.84) 1.84 (1.09, 3.11) Prior psychiatric condition (None ref.) Yes 3.99 (1.96, 8.12) 3.95 (1.82, 8.61) 3.99 (2.14, 7.45) 3.10 (1.60, 6.01) 7.52 (4.44, 12.73) 4.83 (2.65, 8.80) Experienced change in access to basic needsc (No change ref.) Yes 2.65 (1.50, 4.69) 1.67 (0.87, 3.18) 2.79 (1.69, 4.61) 1.99 (1.13, 3.53) 2.82 (1.82, 4.37) 1.81 (1.03, 3.18) Symptom severity (Mild/asymptomatic ref.) Moderate 1.79 (0.65, 4.90) 1.35 (0.50, 3.68) 1.56 (0.76, 3.22) 1.36 (0.60, 3.08) 1.71 (0.85, 3.45) 1.56 (0.75, 3.28) Severe 2.56 (0.97, 6.75) 1.63 (0.61, 4.33) 1.50 (0.75, 3.02) 1.22 (0.56, 2.64) 1.79 (0.92, 3.47) 1.54 (0.73, 3.25) Very Severe 3.57 (1.33, 9.56) 1.39 (0.48, 4.02) 2.04 (0.98, 4.24) 1.52 (0.63, 3.67) 3.30 (1.69, 6.43) 2.81 (1.28, 6.15) Long COVIDd (None ref.) Yes 3.13 (1.80, 5.46) 2.19 (1.10, 4.37) 1.93 (1.16, 3.19) 2.03 (1.09, 3.76) 2.54 (1.66, 3.89) 1.88 (1.14, 3.11) aBold indicates statistical significance at 0.05 level bAdjusted models control for all variables in table, as well as survey type (phone versus online) and survey wave cDefined as inability to access enough food or healthy food, inability to access clean water, or inability to pay important bills (including rent and utilities) dSelf-reported symptom length of at least 60 days Beyond sociodemographic characteristics and comorbidities, experiencing a change in access to basic needs was associated with an elevated RR of anxiety symptoms (aRRR = 1.99; 95% CI = 1.13, 3.53), as well as comorbid depressive/anxiety symptoms (aRRR = 1.81; 95% CI = 1.03, 3.18). Individuals who reported experiencing “very severe” COVID-19 symptoms had a higher RR of experiencing combined depressive/anxiety symptoms (aRRR = 2.81; 95% CI 1.28, 6.15), compared to those with milder symptoms. Finally, Long COVID was associated with depressive symptoms (aRRR = 2.19, 95% CI = 1.10, 4.37), anxiety symptoms (aRRR = 2.03, 95% CI = 1.09, 3.76), and comorbid depressive/anxiety symptoms (aRRR = 1.88, 95% CI = 1.14, 3.11). Results from analyses excluding individuals with missing information on income were largely similar to the primary analysis in direction and statistical significance, except that the association between age (ages 45–54) and experiencing depressive symptoms became marginally non-significant (Supplemental Table 1). Discussion Within a population-based sample of adults in Michigan who experienced a COVID-19 diagnosis prior to August 2020, approximately one-quarter reported recent symptoms of depression and/or anxiety. This estimate is lower than in some prior studies. For example, a meta-analysis of mental health outcomes among people diagnosed with COVID-19 estimated a pooled prevalence of 45% for current depressive symptoms and 47% for anxiety symptoms [19], while another review suggested that 30% of hospitalized COVID-19 patients may experience persistent cognitive impairment, depression, or anxiety, potentially months following diagnosis [20]. The lower prevalence of poor mental health outcomes in this study may stem in part from the population surveyed. Many studies of adults with COVID-19 have focused on hospitalized patient populations, who represent a subset of individuals with severe illness. However, we analyzed a probability sample of all recorded cases in the Michigan Disease Surveillance System, including hospitalized (21%) and non-hospitalized (79%) individuals. Consequently, we characterized depressive and anxiety symptoms across a spectrum of COVID-19 symptom severity levels. In our study, nearly 40% of those who had experienced “very severe symptoms” of acute COVID-19 illness reported at least some depressive and/or anxiety symptoms, compared to less than 20% among individuals with mild/asymptomatic acute illness. Likewise, 39% of individuals who experienced Long COVID reported recent depressive and/or anxiety symptoms, compared to 20.6% among those who did not experience Long COVID. Differences between our analysis and prior studies may also be due to the limited time period of the mental health assessment (e.g., past 2 weeks) as well as the timing of the survey relative to illness onset, as interviews were conducted several months after the acute phase of COVID-19 infection. We found that mental health outcomes differed across sociodemographic groups and were generally consistent with patterns of mental health outcomes observed in the broader population, including patterns observed during the COVID-19 pandemic [6, 39]. For example, a survey of the U.S. population in an early phase of the pandemic (June 2020) found that younger adults (ages 18–24) were more likely to report worse mental health outcomes compared to older adults [6]. Likewise, Hispanic respondents had a higher prevalence of anxiety and depressive symptoms, compared to respondents in other racial/ethnic groups [6]. We also found a higher likelihood of anxiety and combined anxiety/depressive symptoms among younger respondents in our sample. Compared to other racial/ethnic groups, Hispanic respondents had a higher likelihood of depressive only symptoms in our sample, however, this pattern was not observed for other outcomes. In contrast to a prior study of mental health outcomes among adults diagnosed with COVID-19 [22], we found that females were more likely to report symptoms of poor mental health, compared to males. Building on prior literature, these findings shed light on groups that may be at particularly high risk for depressive or anxiety symptoms associated with a COVID-19 infection as well as those that may be at dual risk for both COVID-19 infections and subsequent poor mental health outcomes. For example, adults with lower SES may be more susceptible to COVID-19 infections due to employment, neighborhood, and housing environments [40, 41]; in our study, adults with lower income also experienced a higher prevalence of comorbid depressive/anxiety symptoms following a COVID-19 diagnosis. We also examined the extent to which pandemic- and illness-related factors were independently associated with depressive and anxiety symptoms, after adjusting for demographic characteristics and pre-existing conditions. Our results are in line with prior studies that have found that severity of COVID-19 illness is associated with poor mental health outcomes [11, 22, 25, 26]. In our sample, individuals diagnosed with COVID-19 faced multiple, overlapping risk factors for poor mental health outcomes, including both physical symptoms associated with COVID-19 and economic disruptions due to the pandemic. We found that self-reported symptom severity, Long COVID, and experiencing a change in ability to access basic needs were all independently associated with poor mental health outcomes in adjusted models. Moreover, these factors were highly prevalent in our sample. Over 30% of respondents reported symptoms lasting more than 60 days and over 50% reported a change in access to basic needs associated with the pandemic, including a change in access to enough or healthy food, access to clean water, or the ability to pay important bills. These results imply that addressing the mental health burden associated with COVID-19 will likely require a multi-faceted response that acknowledges long-term symptom burden as well as the impact of the pandemic on other aspects of wellbeing. Strengths of this study include the use of a population-based sample, representative of all recorded cases of COVID-19 in Michigan’s disease tracking system. The use of a probability sample mitigates concerns about internal and external validity in highly selected patient populations, and provides estimates of rates and associations that are relevant for an entire population of COVID-19 survivors in the US State of Michigan. We constructed weights to account for non-response. Our survey tool covered a wide range of topics, which enabled us to explore predictors of mental health outcomes across demographic, physical, and economic domains. Our study also had several limitations. Interviews were conducted several months after infection, so we were not able to assess mental health during the acute phase of COVID-19 illness, or trajectories of mental health outcomes over time [42, 43]. Likewise, our analysis was cross-sectional, and the validity of information was subject to respondent recall and reporting. Our sample is representative only of the subset of all individuals with COVID-19 who received a positive PCR test and were recorded in the MDSS with non-missing address and phone number information. It is likely that a substantial number of cases went undetected, particularly in the early phases of the pandemic, due to limitations on testing eligibility and access. Likewise, 5–18% of the potentially eligible sample in each wave was missing phone number or address information, which could lead to selection bias. Our outcome measure was based on two-item screener questions for depressive and anxiety symptoms, which do not represent clinical diagnoses. The goals of our study were primarily descriptive, and not causal. Patterns of depressive/anxiety symptoms observed in this study may help guide future research into the potential for targeted mental health interventions among highly impacted population subgroups, as well as potential causal mechanisms linking factors (e.g., somatic symptoms associated with Long COVID) to mental health outcomes. It is possible that some associations explored in our study reflect temporal ambiguity, in which pre-existing (undiagnosed or unreported) depressive and anxiety symptoms preceded the “predictive” factors explored in this analysis (e.g., changes in access to basic needs during the pandemic). Because we did not sample individuals without a COVID-19 diagnosis, we were unable to compare the prevalence of anxiety and/or depressive symptoms within our sample to individuals without a documented positive COVID-19 PCR test. Finally, our study focused on the state of Michigan, early in the pandemic. COVID-19-related policies that were in place in Michigan through the end of the study period included a mask order (beginning April 27, 2020) and restaurant and bar closures (beginning March 16, 2020). A stay-at-home order was also in place from March 24, 2020 through June 1, 2020 [44]. While this policy environment was largely in line with many other U.S. states early in the pandemic, [44] we cannot guarantee that results from this study are generalizable to other geographical contexts, or other stages of the pandemic. Among a probability sample of adults who had been diagnosed with COVID-19 in Michigan, we found that approximately one in four reported experiencing depressive and/or anxiety symptoms in the months following diagnosis. By highlighting differential patterns of mental health outcomes, the results of this study shed light on high-risk groups that may benefit from supportive mental health interventions, including individuals who have experienced pandemic-related disruptions to economic wellbeing, and those who have experienced particularly severe or long-lasting symptoms. Pandemic- and illness-specific risk factors identified in this study underscore the need for a robust and integrative clinical and public health response to address the potential for depressive and anxiety symptoms among individuals diagnosed with COVID-19. Supplementary Information Below is the link to the electronic supplementary material.Supplementary file1 (DOCX 21 kb) Acknowledgements We would like to thank the Michigan COVID-19 Recovery Surveillance Study participants and interviewers for making this study possible. We would also like to acknowledge Yanmei Xie for her assistance with imputation. Funding The Michigan COVID-19 Recovery Surveillance Study has received funding from the Michigan Department of Health and Human Services, the Michigan Public Health Institute, the University of Michigan Institute for Data Science, the University of Michigan Rogel Cancer Center, and the University of Michigan Epidemiology Department. This manuscript is supported by the Centers for Disease Control and Prevention of the U.S. Department of Health and Human Services (HHS) funded by CDC/HHS through grant number 6 NU50CK000510-02-04. The contents are those of the authors and do not necessarily represent the official views of, nor an endorsement, by CDC/HHS, or the U.S. Government. Andrea R. Titus was supported by the Agency for Health Care Research and Quality (Grant No.: T32HS026120). Data availability Although the dataset used in this study is not currently available to others, we are in the process of making a de-identified dataset and data dictionary available. Declarations Conflict of interest The authors declare that they have no conflict of interest. ==== Refs References 1. Holmes EA O’Connor RC Perry VH Multidisciplinary research priorities for the COVID-19 pandemic: a call for action for mental health science Lancet Psychiatry 2020 10.1016/S2215-0366(20)30168-1 32563319 2. Kumar A Nayar KR COVID 19 and its mental health consequences J Ment Health 2021 30 1 2 10.1080/09638237.2020.1757052 32339041 3. Rajkumar RP COVID-19 and mental health: a review of the existing literature Asian J Psychiatry 2020 52 102066 10.1016/j.ajp.2020.102066 4. Torales J O’Higgins M Castaldelli-Maia JM Ventriglio A The outbreak of COVID-19 coronavirus and its impact on global mental health Int J Soc Psychiatry 2020 66 317 320 10.1177/0020764020915212 32233719 5. Xiong J Lipsitz O Nasri F Impact of COVID-19 pandemic on mental health in the general population: a systematic review J Affect Disord 2020 277 55 64 10.1016/j.jad.2020.08.001 32799105 6. Czeisler MÉ Lane RI Petrosky E Mental health, substance use, and suicidal ideation during the COVID-19 pandemic — United States, June 24–30, 2020 MMWR Morb Mortal Wkly Rep 2020 69 1049 1057 10.15585/mmwr.mm6932a1 32790653 7. Vahratian A Blumberg SJ Terlizzi EP Schiller JS Symptoms of anxiety or depressive disorder and use of mental health care among adults during the COVID-19 pandemic — United States, August 2020–February 2021 MMWR Morb Mortal Wkly Rep 2021 70 490 494 10.15585/mmwr.mm7013e2 33793459 8. Druss BG Addressing the COVID-19 pandemic in populations with serious mental illness JAMA Psychiat 2020 77 891 892 10.1001/jamapsychiatry.2020.0894 9. Yao H Chen J-H Xu Y-F Patients with mental health disorders in the COVID-19 epidemic The Lancet Psychiatry 2020 7 e21 10.1016/S2215-0366(20)30090-0 32199510 10. Nalleballe K Reddy Onteddu S Sharma R Spectrum of neuropsychiatric manifestations in COVID-19 Brain Behav Immun 2020 88 71 74 10.1016/j.bbi.2020.06.020 32561222 11. Guo Q Zheng Y Shi J Immediate psychological distress in quarantined patients with COVID-19 and its association with peripheral inflammation: a mixed-method study Brain Behav Immun 2020 88 17 27 10.1016/j.bbi.2020.05.038 32416290 12. Perlmutter A Immunological interfaces: the COVID-19 pandemic and depression Front Neurol 2021 12 657004 10.3389/fneur.2021.657004 33967944 13. Szcześniak D Gładka A Misiak B The SARS-CoV-2 and mental health: From biological mechanisms to social consequences Prog Neuropsychopharmacol Biol Psychiatry 2021 104 110046 10.1016/j.pnpbp.2020.110046 32730915 14. Hu Y Chen Y Zheng Y Factors related to mental health of inpatients with COVID-19 in Wuhan, China Brain Behav Immun 2020 89 587 593 10.1016/j.bbi.2020.07.016 32681866 15. Malik P Patel K Pinto C Post-acute COVID-19 syndrome (PCS) and health-related quality of life (HRQoL)-A systematic review and meta-analysis J Med Virol 2022 94 253 262 10.1002/jmv.27309 34463956 16. van Kessel SAM Olde Hartman TC Lucassen PLBJ van Jaarsveld CHM Post-acute and long-COVID-19 symptoms in patients with mild diseases: a systematic review Fam Pract 2022 39 159 167 10.1093/fampra/cmab076 34268556 17. Burton A Aughterson H Fancourt D Philip KEJ Factors shaping the mental health and well-being of people experiencing persistent COVID-19 symptoms or “long COVID”: qualitative study BJPsych Open 2022 8 e72 10.1192/bjo.2022.38 35307048 18. Long COVID. In: NIH COVID-19 Research. https://covid19.nih.gov/covid-19-topics/long-covid. Accessed 4 Nov 2022 19. Deng J Zhou F Hou W The prevalence of depression, anxiety, and sleep disturbances in COVID-19 patients: a meta-analysis Ann N Y Acad Sci 2021 1486 90 111 10.1111/nyas.14506 33009668 20. Nakamura ZM Nash RP Laughon SL Rosenstein DL Neuropsychiatric complications of COVID-19 Curr Psychiatry Rep 2021 23 25 10.1007/s11920-021-01237-9 33725218 21. Taquet M Geddes JR Husain M 6-month neurological and psychiatric outcomes in 236 379 survivors of COVID-19: a retrospective cohort study using electronic health records Lancet Psychiatry 2021 8 416 427 10.1016/S2215-0366(21)00084-5 33836148 22. Perlis RH Ognyanova K Santillana M Association of acute symptoms of COVID-19 and symptoms of depression in adults JAMA Netw Open 2021 4 e213223 10.1001/jamanetworkopen.2021.3223 33710287 23. Chapman DP Perry GS Strine TW The vital link between chronic disease and depressive disorders Prev Chronic Dis 2004 2 A14 15670467 24. Terlizzi EP Villarroel MA Symptoms of generalized anxiety disorder among adults: United States, 2019 2020 Hyattsville, MD National Center for Health Statistics 25. Liu D Baumeister RF Veilleux JC Risk factors associated with mental illness in hospital discharged patients infected with COVID-19 in Wuhan, China Psychiatry Res 2020 292 113297 10.1016/j.psychres.2020.113297 32707218 26. Aiyegbusi OL Hughes SE Turner G Symptoms, complications and management of long COVID: a review J R Soc Med 2021 114 428 10.1177/01410768211032850 34265229 27. Kompaniyets L Body mass index and risk for COVID-19–related hospitalization, intensive care unit admission, invasive mechanical ventilation, and death — United States, March–December 2020 MMWR Morb Mortal Wkly Rep 2021 10.15585/mmwr.mm7010e4 34529635 28. Gao Y Ding M Dong X Risk factors for severe and critically ill COVID-19 patients: a review Allergy 2021 76 428 455 10.1111/all.14657 33185910 29. Tam K-M Walker N Moreno J Effect of mitigation measures on the spreading of COVID-19 in hard-hit states in the US PLoS ONE 2020 15 e0240877 10.1371/journal.pone.0240877 33141823 30. (2022) MDHHS Bureau of EMS, Trauma and Preparedness. https://www.michigan.gov/mdhhs/0,5885,7-339-71548_54783_54826_56171-237197--,00.html. Accessed 19 Jan 2022 31. Cox BG (1980) The weighted sequential hot deck imputation procedure. ASA Proc Section on Survey Res Methods 721–726 32. Mayer DB (2013) Hot deck propensity score imputation for missing values. Sci J Med Clin Trials 2 33. The American Association for Public Opinion Research (2016) Standard definitions: final dispositions of case codes and outcome rates for surveys, 9th edition. AAPOR 34. Kroenke K Spitzer RL Williams JBW The patient health questionnaire-2: validity of a two-item depression screener Med Care 2003 41 1284 1292 10.1097/01.MLR.0000093487.78664.3C 14583691 35. Sapra A Bhandari P Sharma S Using Generalized Anxiety Disorder-2 (GAD-2) and GAD-7 in a primary care setting Cureus 2020 10.7759/cureus.8224 33072453 36. CDC (2020) COVID-19 and Your Health. In: Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/long-term-effects/index.html. Accessed 10 Oct 2021 37. Hirschtick JL Titus AR Slocum E Population-based estimates of post-acute sequelae of SARS-CoV-2 infection (PASC) prevalence and characteristics: a cross-sectional study medRxiv 2021 10.1101/2021.03.08.21252905 38. (2000) Stata Technical Bulletin. https://www.stata.com/products/stb/journals/stb53.pdf. Accessed 23 Nov 2022 39. O’Connor RC Wetherall K Cleare S Mental health and well-being during the COVID-19 pandemic: longitudinal analyses of adults in the UK COVID-19 mental health & wellbeing study Br J Psychiatry 2021 218 326 333 10.1192/bjp.2020.212 33081860 40. Emeruwa UN Ona S Shaman JL Associations between built environment, neighborhood socioeconomic status, and SARS-CoV-2 infection among pregnant women in New York City JAMA 2020 324 390 392 10.1001/jama.2020.11370 32556085 41. McClure ES Vasudevan P Bailey Z Racial capitalism within public health-how occupational settings drive COVID-19 disparities Am J Epidemiol 2020 189 1244 1253 10.1093/aje/kwaa126 32619007 42. Mazza MG De Lorenzo R Conte C Anxiety and depression in COVID-19 survivors: role of inflammatory and clinical predictors Brain Behav Immun 2020 89 594 600 10.1016/j.bbi.2020.07.037 32738287 43. Sun N Wei L Wang H Qualitative study of the psychological experience of COVID-19 patients during hospitalization J Affect Disord 2021 278 15 22 10.1016/j.jad.2020.08.040 32949869 44. Raifman J, Nicka K, Jones D, et al (2020) COVID-19 US state policy database. https://statepolicies.com/policies-by-state/. Accessed 4 Nov 2022
PMC010xxxxxx/PMC10014481.txt	==== Front Clin Imaging Clin Imaging Clinical Imaging 0899-7071 1873-4499 Published by Elsevier Inc. S0899-7071(23)00056-6 10.1016/j.clinimag.2023.03.007 Cardiothoracic Imaging The association of clinically relevant variables with chest radiograph lung disease burden quantified in real-time by radiologists upon initial presentation in individuals hospitalized with COVID-19 Levy Todd a1 Makhnevich Alex bc1 Barish Matthew c Zanos Theodoros P. abc1 Cohen Stuart L. bc1⁎ a Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr., Manhasset, NY 11030, United States of America b Institute of Health System Science, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr., Manhasset, NY 11030, United States of America c Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Northwell Health, 500 Hofstra Blvd., Hempstead, NY 11549, United States of America ⁎ Corresponding author at: Institute of Health System Science, Feinstein Institutes for Medical Research, 350 Community Dr., Manhasset, NY 11030, United States of America. 1 Authors contributed equally 15 3 2023 9 2023 15 3 2023 101 5665 25 7 2022 24 2 2023 8 3 2023 © 2023 Published by Elsevier Inc. 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Objectives We aimed to correlate lung disease burden on presentation chest radiographs (CXR), quantified at the time of study interpretation, with clinical presentation in patients hospitalized with coronavirus disease 2019 (COVID-19). Material and methods This retrospective cross-sectional study included 5833 consecutive adult patients, aged 18 and older, hospitalized with a diagnosis of COVID-19 with a CXR quantified in real-time while hospitalized in 1 of 12 acute care hospitals across a multihospital integrated healthcare network between March 24, 2020, and May 22, 2020. Lung disease burden was quantified in real-time by 118 radiologists on 5833 CXR at the time of exam interpretation with each lung annotated by the degree of lung opacity as clear (0%), mild (1–33%), moderate (34–66%), or severe (67–100%). CXR findings were classified as (1) clear versus disease, (2) unilateral versus bilateral, (3) symmetric versus asymmetric, or (4) not severe versus severe. Lung disease burden was characterized on initial presentation by patient demographics, co-morbidities, vital signs, and lab results with chi-square used for univariate analysis and logistic regression for multivariable analysis. Results Patients with severe lung disease were more likely to have oxygen impairment, an elevated respiratory rate, low albumin, high lactate dehydrogenase, and high ferritin compared to non-severe lung disease. A lack of opacities in COVID-19 was associated with a low estimated glomerular filtration rate, hypernatremia, and hypoglycemia. Conclusions COVID-19 lung disease burden quantified in real-time on presentation CXR was characterized by demographics, comorbidities, emergency severity index, Charlson Comorbidity Index, vital signs, and lab results on 5833 patients. This novel approach to real-time quantified chest radiograph lung disease burden by radiologists needs further research to understand how this information can be incorporated to improve clinical care for pulmonary-related diseases.. An absence of opacities in COVID-19 may be associated with poor oral intake and a prerenal state as evidenced by the association of clear CXRs with a low eGFR, hypernatremia, and hypoglycemia. Keywords Chest radiograph (CXR) Coronavirus disease 2019 (COVID-19) Lung disease Disease severity Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ==== Body pmc1 Introduction Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, has resulted in millions of deaths worldwide.1 The virus primarily affects the lungs and leads to respiratory failure.2., 3. Chest radiographs (CXRs) are the first-line imaging modality utilized to assess the extent of lung involvement in this, as well as other, infectious respiratory diseases.4., 5., 6. Age and comorbidities such as kidney disease and chronic lung disease are associated with disease severity and mortality in individuals hospitalized with COVID-19, though the association of CXR disease severity with these variables remains unclear. Further, a patient's hydration status may limit the ability of a CXR to accurately represent the radiographic disease severity,7 and, as a result, the clinical disease burden in dehydrated or hypovolemic patients. At the time of radiologist interpretation, CXR findings—to help understand disease severity of COVID-19 upon hospital admission in various populations with variable presentations—need further exploration, especially in hospital settings. Prior studies found that CXRs were predictive for patient-centered outcomes in patients with COVID-19.8., 9., 10., 11., 12., 13., 14., 15., 16. However, these prior studies evaluated CXR retrospectively in research settings under ideal conditions or with artificial intelligence (AI)—both difficult to accomplish in real-time settings in diverse environments. In our institution, we developed a mechanism used on nearly 40,000 CXRs to quantify lung disease burden in real-time by radiologists at the time of exam interpretation. This method can become an important research/clinical/operations tool as it may provide predictive abilities to assist efficient patient triage. The association between emergency department (ED) CXR disease severity and clinically relevant variables in patients admitted for COVID-19 is incompletely understood. The purpose of this study is to correlate clinical presentation with COVID-19 lung disease burden on presentation CXRs, quantified in real-time by radiologists at the time of initial exam interpretation. This novel approach to real-time lung disease burden collection can be adapted for use in many real-time lung diseases. 2 Material and methods 2.1 Study design, setting, and population This retrospective cross-sectional study included consecutive adult patients (i.e., aged 18 and older) with a diagnosis of COVID-19 and a CXR quantified in real-time while hospitalized in 1 of 12 acute care hospitals across a multihospital integrated healthcare network in the New York metropolitan region between March 24, 2020, and May 22, 2020. Diagnosis of COVID-19 was confirmed by a positive result on at least one polymerase chain reaction test during hospitalization. During the time of the study at our institution, all ED patients and inpatients with single-view CXRs had them quantified in real-time at the time of exam interpretation by the performing radiologist. Only the first radiograph, per patient, was included in the analysis. The study was performed with institutional review board (IRB) approval and waiver of informed consent. 2.2 Data source Data was obtained from the radiology information system (RIS) and the enterprise inpatient electronic health record (EHR; Sunrise Clinical Manager, Allscripts, Chicago, IL). 2.3 Image acquisition, image analysis and data capture CXRs were obtained in either the posteroanterior (PA) view or the anteroposterior (AP) view. All patients were asked to take a deep breath in and hold it for exam acquisition, if possible. PA exam protocol uses automatic exposure control. AP exam protocol uses manual technique using preset settings based on patient size (small, medium, and large) that is picked by the technologist (approximate average of 2.5 mAs and 90 kV). Lung disease burden was quantified in real-time by radiologists at the time of exam interpretation with each lung annotated by the degree of opacity via visual inspection: clear (0%), mild (1–33%), moderate (34–66%), or severe (67–100%) (Fig. 1 ). This was performed using discrete fields in the radiology reporting software (via a pop-up) upon a radiologist's finalization of a CXR report on nearly 40,000 CXRs with results stored in a secure database. If the radiologist reported lung opacity in the report using the reporting system template, the data was stored in the radiology database without the use of a pop-up. Radiologists were not blinded to patient medical records at the time of image interpretation.Fig. 1 a. 54 year old male with dyspnea and clear lungs bilaterally. b. 60 year old male with fever, cough, and dyspnea and mild disease bilaterally with subtle bilateral lung opacities. c. 53 year old male with dyspnea and moderate disease bilaterally with ill-defined patchy and linear opacities bilaterally. d. 73 year old male with cough, fever, and dyspnea with severe disease bilaterally as seen by patchy and consolidative bilateral lung opacities. Fig. 1 2.4 Lung disease burden classification/outcomes The following 4 outcomes were defined based on the opacities of the left and right lungs in the CXRs: (1) clear versus disease, (2) unilateral versus bilateral, (3) symmetric versus asymmetric, and (4) not severe versus severe (see Supplement Table 4 for definitions). Only binomial outcomes were considered, and patients that were labeled “clear” were only used in the analysis of clear versus disease (see Supplement Table 4). Patients without opacities were not used in the analysis of unilateral versus bilateral, symmetric versus asymmetric and not severe versus severe lung disease burden. Because of human error and potential overlapping categories, we allowed for symmetric disease to include the same category in each lung or one category away. 2.5 Independent variables We collected data on patient demographics, comorbidities, vital signs, and lab results and reported them as categorical variables. We used patient-reported race and ethnicity to categorize patients into 1 of 5 groups for race (Asian, Black, White, Other, Unknown/Declined) and one of three groups for ethnicity (Ethnicity Unknown/Declined; Ethnicity Hispanic or Latino, Ethnicity Not Hispanic or Latino). Comorbidities were chosen based on data from previous publications17., 18., 19., 20. and included the following diagnoses based on Tenth Revision (ICD-10) coding: congestive heart failure (CHF), lung disease, kidney disease, diabetes, coronary artery disease (CAD), and hypertension (HTN). We identified the following comorbidities by International Statistical Classification of Disease and Related Health Problems, Tenth Revision (ICD-10) coding (see Supplement Table 1 for ICD-10 codes): coronary artery disease (CAD), hypertension, lung disease, kidney disease, diabetes (DM), or heart failure (HF). We calculated the Charlson Comorbidity Index (CCI) as a measure of total comorbidity burden and categorized results into 3 groups: 0–5, 6–10, or >10. The emergency severity index (ESI), a tool for EDs at the time of triage, is scored from 1 (most urgent) to 5 (least urgent). The estimated glomerular filtration rate (eGFR) was extracted from the EHR. Systolic blood pressure (SBP), diastolic blood pressure (DBP), respiratory rate (RR), temperature (Temp), and heart rate (HR) were categorized as low, normal, and high (see Supplement Table 2). Oxygen (O2) impairment was defined as none, mild, moderate, or severe based on the level of oxygen saturation (SpO2) and supplemental oxygen requirements (oxygen delivery method) (see Supplement Table 3). The lab results other than d-dimer and C-reactive protein (CRP) were categorized as being low, normal, or high based on the predefined ranges from the specific assays that were performed. D-dimer and CRP were categorized as normal or high. 2.6 Data analysis Nearest-neighbor interpolation of vitals and labs to the time of radiograph was performed. The time-varying measurements that include vital signs and lab results were interpolated using nearest-neighbor interpolation to the time of the first CXR in a series of CXRs for each patient. Nearest neighbor interpolation can select values recorded before or after the time of the CXR and was used regardless of the duration between the time of the radiograph and the time of the measurement, even though most of the measurement occurred within a short time after the CXR was taken (see Supplemental Table 4). Some lab values were not measured at all for certain patients and were assigned to the category “not recorded.” 2.7 Outcome analysis Univariate analysis was performed using chi-square and multivariate analysis was performed using logistic regression. Some measurements were labeled as “not recorded,” and this resulted in degenerate patterns of missingness (the input matrix for the multivariate analysis was not full rank) because these missing measurements were not missing completely at random. This problem was alleviated by removing Eosinophil and Alanine Aminotransferase from the analysis. The 95% confidence intervals (CIs) on the adjusted odds ratios (ORs) were determined using the adjusted log OR coefficients, adding and subtracting 1.96 times the standard error, and exponentiating the result. All analyses were performed using MATLAB 2019b and its statistics and machine learning toolbox (Mathworks, Natick, MA). 3 Results 3.1 Patient population A total of 5833 patients were included in this study; of these, 2427 (41.6%) were female (see Table 1 ). The age distribution was 360 (6.2%), 1485 (25.5%), 2685 (46.0%), 1303 (22.3%) who were respectively aged 18–40, 41–60, 61–80, and 81–106 years. Overall, 1149 (19.7%) were Black, 1208 (20.7%) were Hispanic or Latino, and 1353 (23.2%), had a CCI of 6 or higher.Table 1 Demographics. Table 1Category N (%) Age 18–40 360 (6.2%) 41–60 1485 (25.5%) 61–80 2685 (46.0%) 81–106 1303 (22.3%) Gender Female 2427 (41.6%) Male 3406 (58.4%) Race Asian 524 (9.0%) Black 1149 (19.7%) Unknown/declined 268 (4.6%) Other 1553 (26.6%) White 2339 (40.1%) Ethnicity Unknown/declined 374 (6.4%) Hispanic or Latino 1208 (20.7%) Not Hispanic or Latino 4251 (72.9%) Charlson Comorbidity Index 0–5 2199 (37.7%) 6–10 1353 (23.2%) >10 404 (6.9%) Not recorded 1877 (32.2%) Heart failure No 3505 (60.1%) Yes 455 (7.8%) Not recorded 1873 (32.1%) Lung disease No 1652 (28.3%) Yes 2308 (39.6%) Not recorded 1873 (32.1%) Kidney disease No 3326 (57.0%) Yes 634 (10.9%) Not recorded 1873 (32.1%) Diabetes No 2400 (41.1%) Yes 1560 (26.7%) Not recorded 1873 (32.1%) Coronary artery disease No 3352 (57.5%) Yes 608 (10.4%) Not recorded 1873 (32.1%) Hypertension No 3548 (60.8%) Yes 412 (7.1%) Not recorded 1873 (32.1%) Heart rate <60 189 (3.2%) 60–99 3936 (67.5%) >99 1333 (22.9%) Not recorded 375 (6.4%) Emergency severity index 1 202 (3.5%) 2 2258 (38.7%) 3 1394 (23.9%) 4 26 (0.4%) Not recorded 1953 (33.5%) O2 impairment Normal 1893 (32.5%) Mild 1655 (28.4%) Moderate 1153 (19.8%) Severe 750 (12.9%) Not recorded 372 (6.4%) Systolic blood pressure Low 428 (7.3%) Normal 4905 (84.1%) High 109 (1.9%) Not recorded 391 (6.7%) Diastolic blood pressure Low 917 (15.7%) Normal 4411 (75.6%) High 113 (1.9%) Not recorded 392 (6.7%) Respiratory rate Low 38 (0.7%) Normal 2724 (46.7%) High 2690 (46.1%) Not recorded 381 (6.5%) Temperature Low 245 (4.2%) Normal 4461 (76.5%) High 738 (12.7%) Not recorded 389 (6.7%) Hemoglobin Low 2807 (48.1%) Normal 2861 (49.0%) High 133 (2.3%) Not recorded 32 (0.5%) White blood cell count Low 290 (5.0%) Normal 3239 (55.5%) High 2266 (38.8%) Not recorded 38 (0.7%) Red cell distribution width Low 4 (0.1%) Normal 3539 (60.7%) High 2257 (38.7%) Not recorded 33 (0.6%) Platelet count Low 809 (13.9%) Normal 4284 (73.4%) High 706 (12.1%) Not recorded 34 (0.6%) Estimated glomerular filtration rate Low 2199 (37.7%) Normal 3555 (60.9%) Not recorded 79 (1.4%) Glucose Low 64 (1.1%) Normal 747 (12.8%) High 4943 (84.7%) Not recorded 79 (1.4%) Blood urea nitrogen Low 209 (3.6%) Normal 2555 (43.8%) High 2990 (51.3%) Not recorded 79 (1.4%) Bicarbonate (CO2) Low 1517 (26.0%) Normal 4018 (68.9%) High 219 (3.8%) Not recorded 79 (1.4%) Sodium Low 1561 (26.8%) Normal 3497 (60.0%) High 696 (11.9%) Not recorded 79 (1.4%) Creatinine Low 248 (4.3%) Normal 3379 (57.9%) High 2127 (36.5%) Not recorded 79 (1.4%) Potassium Low 562 (9.6%) Normal 4668 (80.0%) High 524 (9.0%) Not recorded 79 (1.4%) Albumin Low 3345 (57.3%) Normal 2393 (41.0%) High 3 (0.1%) Not recorded 92 (1.6%) Alkaline phosphatase Low 105 (1.8%) Normal 4361 (74.8%) High 1275 (21.9%) Not recorded 92 (1.6%) Lymphocyte Low 3267 (56.0%) Normal 2368 (40.6%) High 108 (1.9%) Not recorded 90 (1.5%) Monocyte Low 10 (0.2%) Normal 4474 (76.7%) High 1259 (21.6%) Not recorded 90 (1.5%) Neutrophil Low 96 (1.6%) Normal 2813 (48.2%) High 2834 (48.6%) Not recorded 90 (1.5%) Bilirubin Low 195 (3.3%) Normal 5133 (88.0%) High 413 (7.1%) Not recorded 92 (1.6%) Aspartate aminotransferase Low 52 (0.9%) Normal 2562 (43.9%) High 3127 (53.6%) Not recorded 92 (1.6%) C-reactive protein Normal 252 (4.3%) High 5007 (85.8%) Not recorded 574 (9.8%) Lactate dehydrogenase Low 6 (0.1%) Normal 432 (7.4%) High 3848 (66.0%) Not recorded 1547 (26.5%) D-Dimer Normal 1446 (24.8%) High 3784 (64.9%) Not recorded 603(10.4%) Ferritin Low 18 (0.3%) Normal 697 (11.9%) High 4519 (77.5%) Not recorded 599 (10.3%) The 5833 CXRs on these patients were interpreted by 118 radiologists. The mean and median number of CXRs interpreted by each radiologist was 49.4 and 28.5 respectively. There were 4819 AP CXR, 40 PA CXR, and 973 CXR of unknown (either AP or PA orientation). 3.2 Outcomes Overall, patients were more likely to have disease compared to a clear CXR, bilateral compared to unilateral CXR findings, symmetric compared to asymmetric CXR disease, and severe compared to not severe CXR disease (see Table 2 ). Missing data is reported in Supplement Table 6.Table 2 CXR results. Table 2Category N (%) Lung disease burden Clear (0%) 893 (15.3%) Mild (1–33%) 2380 (40.8%) Moderate (34–66%) 1757 (30.1%) Severe (67–100%) 803 (13.8%) Total 5833 (100.0%) Clear versus disease Clear 893 (15.3%) Disease 4940 (84.7%) Total 5833 (100.0%) Lung burden laterality Clear 893 (15.3%) Unilateral 699 (12.0%) Bilateral 4241 (72.7%) Total 5833 (100.0%) Unilateral 699 (14.1%) Bilateral 4241 (85.9%) Total (excluding clear) 4940 (100.0%) Lung burden severity Clear 893 (15.3%) Not severe 2380 (40.8%) Severe 2560 (43.9%) Total 5833 (100.0%) Not severe 2380 (48.2%) Severe 2560 (51.8%) Total (excluding clear) 4940 (100.0%) Symmetry Symmetric 4719 (95.5%) Asymmetric 221 (4.5%) Total 4940 (100.0%) 3.2.1 CXR lung disease burden: clear versus disease Patients with a clear CXR compared to any disease on CXR were more likely to be of an age of 18–40 years relative to 60–80 years (OR 0.46, 95% CI 0.33, 0.65, p < 0.001) and Black relative to White (OR 0.78 [95% CI 0.62, 0.98], p < 0.05). Further, they were more likely to have low platelets (OR 0.66 [95% CI 0.52, 0.84], p < 0.001), low eGFR (OR 0.70 [95% CI 0.54, 0.91], p < 0.01), low glucose (OR 0.46 [95% CI 0.22, 0.96], p < 0.05), high sodium (OR 0.72 [95% CI 0.54, 0.97], p < 0.05), and high monocytes (OR 0.78 [95% CI 0.62, 0.97], p < 0.05) (see Table 3 ).Table 3 Multivariable analysis. Table 3Category Clear versus disease Unilateral versus bilateral Symmetric versus asymmetric Not severe versus severe Age 18–40 0.46 (0.33, 0.65)*** 0.73 (0.49, 1.09) 1.45 (0.79, 2.67) 1.29 (0.95, 1.75) 41–60 0.80 (0.64, 1.01) 1.00 (0.79, 1.28) 0.72 (0.48, 1.06) 1.15 (0.97, 1.35) 61–80 Reference Reference Reference Reference 81–106 0.98 (0.78, 1.23) 0.83 (0.66, 1.04) 1.02 (0.70, 1.50) 1.03 (0.86, 1.23) Sex Female 0.88 (0.73, 1.06) 0.90 (0.74, 1.09) 1.34 (0.98, 1.82) 0.87 (0.76, 1.00) Male Reference Reference Reference Reference Race Asian 1.16 (0.82, 1.63) 1.12 (0.81, 1.56) 0.67 (0.38, 1.19) 0.94 (0.74, 1.18) Black 0.78 (0.62, 0.98)* 1.20 (0.94, 1.54) 0.73 (0.48, 1.10) 0.97 (0.80, 1.16) Unknown/declined 0.81 (0.45, 1.45) 1.20 (0.66, 2.19) 0.81 (0.35, 1.88) 1.20 (0.81, 1.79) Other 1.14 (0.86, 1.52) 1.14 (0.86, 1.52) 1.06 (0.69, 1.61) 0.94 (0.77, 1.14) White Reference Reference Reference Reference Ethnicity Unknown/declined 1.26 (0.75, 2.11) 1.22 (0.73, 2.04) 1.16 (0.60, 2.24) 0.79 (0.56, 1.10) Hispanic or Latino 1.34 (0.99, 1.81) 1.44 (1.06, 1.95)* 0.56 (0.35, 0.91)* 1.33 (1.09, 1.63) Not Hispanic or Latino Reference Reference Reference Reference CCI 0–5 Reference Reference Reference Reference 6–10 0.80 (0.61, 1.05) 0.64 (0.48, 0.85) 0.68 (0.44, 1.07) 0.75 (0.62, 0.92) >10 0.66 (0.44, 1.01) 0.55 (0.36, 0.85) 0.71 (0.35, 1.43) 0.71 (0.51, 0.98)* Not recorded Inf (0.00, Inf) 0.42 (0.04, 4.43) 0.00 (0.00, Inf) 0.00 (0.00, Inf) Heart failure No Reference Reference Reference Reference Yes 0.85 (0.60, 1.19) 1.69 (1.13, 2.51) 0.65 (0.34, 1.26) 1.31 (1.00, 1.72) Not recorded 0.00 (0.00, Inf) 3.11 (0.27, 36.35) Inf (0.00, Inf) Inf (0.00, Inf) Lung disease No Reference Reference Reference Reference Yes 1.92 (1.52, 2.42)* 1.56 (1.23, 1.97)* 0.85 (0.59, 1.23) 1.31 (1.11, 1.55) Not recorded None None None None Kidney disease No Reference Reference Reference Reference Yes 1.67 (1.15, 2.43)** 0.85 (0.59, 1.23) 1.53 (0.85, 2.76) 1.33 (1.00, 1.75)* Not recorded None None None None Diabetes No Reference Reference Reference Reference Yes 1.07 (0.85, 1.35) 1.18 (0.92, 1.50) 1.05 (0.73, 1.52) 1.02 (0.86, 1.20) Not recorded None None None None CAD No Reference Reference Reference Reference Yes 0.83 (0.61, 1.11) 1.04 (0.75, 1.43) 0.84 (0.49, 1.44) 0.90 (0.71, 1.13) Not recorded None None None None Hypertension No Reference Reference Reference Reference Yes 0.97 (0.63, 1.50) 1.76 (1.09, 2.83)* 1.13 (0.55, 2.31) 1.15 (0.83, 1.61) Not recorded None None None None Heart rate Low 0.65 (0.42, 1.01) 1.25 (0.73, 2.15) 1.18 (0.54, 2.55) 0.80 (0.55, 1.17) Normal Reference Reference Reference Reference High 0.95 (0.76, 1.20) 0.82 (0.66, 1.03) 1.16 (0.82, 1.63) 0.96 (0.82, 1.12) Not recorded 0.95 (0.04, 22.55) 4.71 (0.26, 86.75) 4.31 (0.07, 270.44) 0.90 (0.09, 8.50) ESI 1 0.63 (0.17, 2.33) 0.34 (0.07, 1.75) 0.36 (0.06, 2.19) 1.39 (0.50, 3.88) 2 1.05 (0.32, 3.45) 0.56 (0.12, 2.69) 0.48 (0.09, 2.46) 1.23 (0.47, 3.25) 3 1.03 (0.31, 3.35) 0.60 (0.13, 2.88) 0.34 (0.07, 1.77) 1.19 (0.45, 3.14) 4 Reference Reference Reference Reference Not recorded 1.64 (0.39, 6.84) 0.38 (0.07, 2.11) 1.18 (0.19, 7.26) 1.02 (0.34, 3.08) O2 impairment Normal Reference Reference Reference Reference Mild impairment 2.27 (1.83, 2.83)* 1.87 (1.50, 2.32)* 0.96 (0.65, 1.42) 2.21 (1.86, 2.62)* Moderate impairment 3.97 (2.82, 5.60)* 2.83 (2.11, 3.81)* 1.18 (0.76, 1.84) 4.13 (3.37, 5.08)* Severe impairment 4.47 (2.68, 7.45)* 5.15 (3.24, 8.18)* 0.52 (0.29, 0.96)* 3.78 (2.90, 4.91)* Not recorded 1.55 (0.36, 6.77) 1.09 (0.20, 6.03) 0.11 (0.01, 1.43) 2.21 (0.44, 11.00) SBP Low 0.80 (0.55, 1.17) 0.83 (0.58, 1.20) 1.28 (0.74, 2.23) 0.84 (0.65, 1.09) Normal Reference Reference Reference Reference High 0.65 (0.35, 1.18) 1.83 (0.85, 3.98) 0.75 (0.24, 2.33) 0.79 (0.46, 1.34) Not recorded 0.00 (0.00, Inf) 0.00 (0.00, Inf) Inf (0.00, Inf) Inf (0.00, Inf) DBP Low 1.02 (0.78, 1.35) 1.09 (0.83, 1.43) 0.71 (0.45, 1.11) 1.06 (0.88, 1.29) Normal Reference Reference Reference Reference High 1.27 (0.66, 2.45) 0.60 (0.32, 1.13) 1.41 (0.54, 3.65) 0.98 (0.59, 1.62) Not recorded Inf (0.00, Inf) Inf (0.00, Inf) 0.00 (0.00, Inf) 0.00 (0.00, Inf) RR Low 1.47 (0.51, 4.18) 5.24 (0.67, 40.74) 1.31 (0.29, 6.04) 1.67 (0.76, 3.71) Normal Reference Reference Reference Reference High 1.84 (1.48, 2.28)* 1.23 (1.01, 1.51)* 0.98 (0.71, 1.36) 1.34 (1.16, 1.55)* Not recorded 0.95 (0.12, 7.73) 0.30 (0.03, 3.27) 0.18 (0.00, 8.31) 0.42 (0.07, 2.61) Temperature Low 0.70 (0.45, 1.09) 0.77 (0.48, 1.23) 1.60 (0.83, 3.05) 0.91 (0.65, 1.26) Normal Reference Reference Reference Reference High 0.93 (0.70, 1.25) 0.86 (0.65, 1.12) 2.09 (1.44, 3.03)* 1.04 (0.86, 1.26) Not recorded 0.78 (0.20, 3.06) 4.16 (0.38, 45.76) 2.81 (0.28, 28.02) 2.29 (0.61, 8.61) Hemoglobin Low 1.36 (1.12, 1.66)** 1.04 (0.85, 1.28) 0.95 (0.69, 1.32) 1.16 (1.00, 1.34) Normal Reference Reference Reference Reference High 0.64 (0.39, 1.07) 0.82 (0.46, 1.45) 0.61 (0.18, 2.05) 0.62 (0.40, 0.97)* Not recorded 0.00 (0.00, Inf) Inf (0.00, Inf) 0.92 (0.00, Inf) Inf (0.00, Inf) WBC Low 0.99 (0.65, 1.50) 0.92 (0.60, 1.40) 1.01 (0.50, 2.07) 0.99 (0.70, 1.39) Normal Reference Reference Reference Reference High 1.21 (0.91, 1.60) 0.78 (0.57, 1.05) 0.86 (0.56, 1.31) 1.16 (0.95, 1.41) Not recorded Inf (0.00, Inf) Inf (0.00, Inf) 0.00 (0.00, Inf) 15.65 (1.51, 162.73)* RCDW Low 0.36 (0.02, 5.51) Inf (0.00, Inf) 0.00 (0.00, Inf) 0.38 (0.03, 4.75) Normal Reference Reference Reference Reference High 0.91 (0.74, 1.10) 0.94 (0.77, 1.15) 1.20 (0.87, 1.66) 1.09 (0.93, 1.26) Not recorded 0.25 (0.00, Inf) 0.00 (0.00, Inf) 2.53 (0.00, Inf) 0.00 (0.00, Inf) Platelet Low 0.66 (0.52, 0.84)*** 0.76 (0.59, 0.97)* 1.28 (0.86, 1.91) 0.80 (0.66, 0.97)* Normal Reference Reference Reference Reference High 0.87 (0.65, 1.15) 1.33 (0.97, 1.82) 0.86 (0.53, 1.39) 1.00 (0.82, 1.22) Not recorded Inf (0.00, Inf) Inf (0.00, Inf) 0.00 (0.00, Inf) Inf (0.00, Inf) eGFR low 0.70 (0.54, 0.91) 0.94 (0.72, 1.24) 1.14 (0.72, 1.79) 0.89 (0.72, 1.09) eGFR normal Reference Reference Reference Reference eGFR not recorded 12.00 (2.44, 58.93) 0.00 (0.00, Inf) Inf (0.00, Inf) Inf (0.00, Inf) Glucose Low 0.46 (0.22, 0.96)* 1.54 (0.57, 4.17) 0.39 (0.05, 3.03) 0.98 (0.53, 1.84) Normal Reference Reference Reference Reference High 0.96 (0.76, 1.22) 1.18 (0.92, 1.52) 1.06 (0.68, 1.66) 0.95 (0.77, 1.16) Not recorded None None None None BUN Low 1.11 (0.71, 1.73) 1.20 (0.72, 2.00) 0.68 (0.26, 1.79) 1.08 (0.76, 1.55) Normal Reference Reference Reference Reference High 0.85 (0.67, 1.08) 0.80 (0.62, 1.02) 1.23 (0.83, 1.81) 0.82 (0.69, 0.98)* Not recorded None None None None CO2 Low 0.92 (0.74, 1.13) 1.01 (0.81, 1.24) 0.83 (0.58, 1.19) 0.98 (0.84, 1.15) Normal Reference Reference Reference Reference High 0.88 (0.55, 1.40) 0.95 (0.58, 1.56) 1.28 (0.66, 2.50) 1.48 (1.04, 2.10)* Not recorded None None None None Sodium Low 0.96 (0.78, 1.18) 0.92 (0.75, 1.14) 1.10 (0.79, 1.54) 0.99 (0.85, 1.15) Normal Reference Reference Reference Reference High 0.72 (0.54, 0.97)* 0.58 (0.43, 0.76)* 0.69 (0.43, 1.11) 0.56 (0.45, 0.69)* Not recorded None None None None Creatinine Low 1.28 (0.78, 2.09) 1.34 (0.77, 2.33) 0.91 (0.41, 1.98) 1.22 (0.87, 1.70) Normal Reference Reference Reference Reference High 1.05 (0.80, 1.37) 0.86 (0.65, 1.13) 0.98 (0.62, 1.54) 0.82 (0.66, 1.01) Not recorded None None None None Potassium Low 0.94 (0.70, 1.27) 0.74 (0.55, 0.98)* 1.76 (1.16, 2.68) 0.82 (0.67, 1.02) Normal Reference Reference Reference Reference High 1.12 (0.82, 1.54) 0.80 (0.59, 1.09) 1.13 (0.70, 1.84) 1.10 (0.87, 1.38) Not recorded none none none none Albumin Low 1.70 (1.40, 2.06)* 1.22 (1.00, 1.48) 1.68 (1.19, 2.38) 1.54 (1.34, 1.79)* Normal Reference Reference Reference Reference High 0.00 (0.00, Inf) Na Na Na Not recorded 0.10 (0.02, 0.44) Inf (0.00, Inf) 0.00 (0.00, Inf) 0.00 (0.00, Inf) Alkaline phosphatase Low 0.80 (0.43, 1.51) 1.24 (0.64, 2.41) 0.97 (0.34, 2.79) 0.96 (0.61, 1.53) Normal Reference Reference Reference Reference High 0.83 (0.66, 1.03) 1.16 (0.92, 1.47) 1.07 (0.76, 1.52) 1.11 (0.94, 1.30) Not recorded None None None None Lymphocyte Low 1.32 (1.09, 1.59) 1.56 (1.29, 1.89)*** 1.42 (1.03, 1.98)* 1.25 (1.09, 1.44)** Normal Reference Reference Reference Reference High 0.83 (0.47, 1.48) 1.42 (0.71, 2.85) 2.03 (0.76, 5.41) 0.79 (0.48, 1.29) Not recorded 0.54 (0.01, 31.80) 0.00 (0.00, Inf) 0.00 (0.00, Inf) 0.00 (0.00, Inf) Monocyte Low 1.21 (0.12, 12.08) 2.41 (0.20, 29.78) 0.00 (0.00, Inf) 1.62 (0.33, 7.96) Normal Reference Reference Reference Reference High 0.78 (0.62, 0.97)* 0.95 (0.75, 1.21) 1.35 (0.93, 1.95) 0.88 (0.74, 1.05) Not recorded 1.52 (0.03, 73.20) Inf (0.00, Inf) 0.00 (0.00, Inf) Inf (0.00, Inf) Neutrophil Low 1.00 (0.54, 1.87) 0.48 (0.26, 0.91)* 0.78 (0.21, 2.93) 0.63 (0.34, 1.18) Normal Reference Reference Reference Reference High 0.75 (0.58, 0.98)* 1.30 (0.98, 1.74) 1.32 (0.87, 2.00) 1.05 (0.87, 1.27) Not recorded 1.03 (0.02, 49.48) 2.09 (0.00, Inf) Inf (0.00, Inf) Inf (0.00, Inf) Bilirubin Low 0.86 (0.56, 1.32) 0.65 (0.41, 1.03) 2.06 (1.07, 3.99)* 0.83 (0.58, 1.20) Normal Reference Reference Reference Reference High 0.74 (0.53, 1.03) 1.14 (0.78, 1.65) 0.86 (0.48, 1.53) 1.04 (0.81, 1.35) Not recorded None None None None AST Low 1.40 (0.69, 2.83) 0.68 (0.32, 1.46) 0.55 (0.07, 4.21) 1.08 (0.50, 2.32) Normal Reference Reference Reference Reference High 1.40 (1.16, 1.69)* 0.90 (0.74, 1.09) 1.02 (0.75, 1.39) 1.09 (0.95, 1.25) Not recorded None None None None CRP Normal Reference Reference Reference Reference High 3.00 (2.15, 4.18)* 1.04 (0.64, 1.69) 5.22 (0.71, 38.59) 1.03 (0.70, 1.52) Not recorded 1.87 (1.21, 2.90) 0.99 (0.53, 1.86) 5.55 (0.64, 47.98) 0.88 (0.51, 1.50) Lactate dehydrogenase Low 0.05 (0.00, 1.12) Inf (0.00, Inf) 0.00 (0.00, Inf) Inf (0.00, Inf) Normal Reference Reference Reference Reference High 1.90 (1.43, 2.54)* 1.70 (1.24, 2.34) 1.03 (0.56, 1.91) 1.61 (1.22, 2.12)* Not recorded 1.22 (0.91, 1.64) 1.79 (1.27, 2.53)*** 0.88 (0.44, 1.73) 1.44 (1.06, 1.94)* D-Dimer Normal Reference Reference Reference Reference High 1.31 (1.04, 1.63)* 1.05 (0.83, 1.33) 1.32 (0.87, 2.01) 1.33 (1.12, 1.57)* Not recorded 0.83 (0.60, 1.15) 1.34 (0.89, 2.01) 1.77 (0.86, 3.64) 0.86 (0.61, 1.21) Ferritin Low 0.49 (0.16, 1.52) 0.70 (0.15, 3.40) 0.00 (0.00, Inf) 0.37 (0.04, 3.29) Normal Reference Reference Reference Reference High 1.74 (1.37, 2.22)* 1.93 (1.48, 2.52)* 1.02 (0.61, 1.70) 1.40 (1.13, 1.75) Not recorded 1.15 (0.79, 1.67) 0.74 (0.47, 1.15) 0.80 (0.31, 2.04) 0.94 (0.62, 1.41) Significant variables <0.05, <0.01, **<0.001. CCI-Charlson Comorbidity Index, CAD-coronary artery disease, ESI-emergency severity index, SBP-systolic blood pressure, DBP-diastolic blood pressure, RR-respiratory rate, WBC-white blood cell count, RCDW-red cell distribution width, eGFR-estimated glomerular filtration rate, BUN-blood urea nitrogen, C02-bicarbonate, AST-aspartate aminotransferase, CRP-C-reactive protein. Patients with CXR that demonstrates disease compared to no disease were more likely to have a history of lung disease (OR 1.92 [95% CI 1.52, 2.42], p < 0.001); a history of renal disease (OR 1.67 [95% CI 1.15, 2.43], p < 0.01); mild, moderate, and severe O2 impairment (OR 2.27 [95% CI 1.83, 2.83], p < 0.001, OR 3.97 [95% CI 2.82, 5.60], p < 0.001, OR 4.47 [95% CI 2.68, 7.45], p < 0.001), respectively; elevated respiratory rate (OR 1.84 [95% CI 1.48, 2.28], p < 0.001); low hemoglobin (OR 1.36 [95% CI 1.12, 1.66], p < 0.01); low albumin (OR 1.70 [95% CI 1.40, 2.06], p < 0.001); low lymphocytes (OR 1.32 [95% CI 1.09, 1.59], p < 0.01; high neutrophil OR 0.75 [95% CI 0.58, 0.98], p < 0.05); high Aspartate Aminotransferase (AST) (OR 1.40 [95% CI 1.16, 1.69], p < 0.001); high CRP (OR 3.00 [95% CI 2.15, 4.18], p < 0.001); high lactate dehydrogenase (OR 1.90 [95% CI 1.43, 2.54], p < 0.001); high d-dimer (OR 1.31 [95% CI 1.04, 1.63], p < 0.05); and high ferritin (OR 1.74 [95% CI 1.37, 2.22], p < 0.001). 3.2.2 CXR lung disease burden: severe versus not severe Patients without severe disease on CXR were more likely to have CCI 6–10, CCI >10 (OR 0.75 [95% CI 0.62, 0.92], p < 0.01, OR 0.71 [95% CI 0.51, 0.98], p < 0.05), low platelets (OR 0.80 [95% CI 0.66, 0.97], p < 0.05), and high blood area nitrogen (BUN) (OR 0.82 [95% CI 0.69, 0.98], p < 0.05). Patients with severe disease on CXR were more likely to be Hispanic (OR 1.33 [95% CI 1.09, 1.63], p < 0.01) and more likely to have prior lung disease (OR 1.31 [95% CI 1.11, 1.55], p < 0.01); renal disease (OR 1.33 [95% CI 1.00, 1.75], p < 0.05); mild, moderate, and severe O2 impairment (OR 2.21 [95% CI 1.86, 2.62], p < 0.001, OR 4.13 [95% CI 3.37, 5.08], p < 0.001, OR 3.78 [95% CI 2.90, 4.91], p < 0.001); elevated respiratory rate (RR) (OR 1.34 [95% CI 1.16, 1.55], p < 0.001); high bicarbonate (OR 1.48 [95% CI 1.04, 2.10], p < 0.05); low albumin (OR 1.54 [95% CI 1.34, 1.79], p < 0.001); low lymphocytes (OR 1.25 [95% CI 1.09, 1.44], p < 0.01); high lactate dehydrogenase (OR 1.61 [95% CI 1.22, 2.12], p < 0.001); and high ferritin (OR 1.40 [95% CI 1.13, 1.75], p < 0.01). For univariable results, refer to Supplement Table 6. For multivariable results of unilateral versus bilateral and asymmetric versus asymmetric disease, refer to Table 3. 4 Discussion This retrospective cross-sectional study shows the ability to correlate clinical presentation with COVID-19 lung disease burden on presentation CXRs using images quantified in real-time by radiologists at the time of initial exam interpretation. Patients with CXRs that demonstrated disease (compared to no disease) or severe disease (compared to no severe disease) were more likely to be older, have mild or moderate O2 impairment, as well as known markers associated with more severe COVID-19,17., 18., 19., 21., 22., 23., 24., 25. such as underlying lung and renal disease, severe O2 impairment, elevated respiratory rate, low albumin, high lactate dehydrogenase, and high ferritin. No differences were found between male and female sex. While prior studies have evaluated chest imaging in the setting of COVID-19, they have not quantified lung disease burden in real-time by a radiologist at the time of exam interpretation. Some of these studies evaluated CXR lung disease burden retrospectively in research settings under ideal conditions, while other studies used AI. Both retrospective studies and AI are difficult to implement clinically in real-time settings in diverse environments. Specifically, the RALE26 and BRIXIA27 scores. For example, the RALE score divides the lungs into 4 zones and gives each a consolidation score from 0 to 4 and a density score from 1 to 3. The BRIXIA score divides the lungs into 6 zones and gives each a score from 0 to 3. Given the cumbersome nature of obtaining these scores it was not practical to obtain them in real-time. Further, a recent meta-analysis of CXR scores in COVID did not assess if the scores were obtained in real-time or retrospectively28. Also, the largest series in the meta-analysis had 636 patients and was obtained retrospectively29. This is compared to our methodology that was able to obtain scores on nearly 40,000 CXR in real-time, with 5833 used for this study. Our method allowed radiologists to quantify lung disease burden on a large volume of CXRs, at the time of exam interpretation, with minimal disruption to work-flow during a time of unprecedented stress. Radiologists typically do not quantify degree of lung opacity on CXR reports. We show that this annotation scheme can be helpful to provide a standardized mechanism for providers to understand degree of disease. Further research is needed to understand how this information can be incorporated to improve clinical care for pulmonary-related diseases. We were also able to develop a logic that combined patient oxygen saturation with oxygen delivery methods to fully account for the level of O2 impairment. To the best of our knowledge, we are the first to use quantified lung disease burden in real-time by radiologists at the time of exam interpretation, combine these findings with oxygen saturation and oxygen delivery (i.e., to convey severity of oxygen impairment), and associate these findings with any CXR evidence of COVID-19 (compared to no disease) and severe CXR disease (compared to non-severe). Interestingly, our findings suggest that the lack of opacities in COVID-19 may be associated with poor oral intake and a prerenal state as evidenced by the association of clear CXRs with a low eGFR, hypernatremia, and hypoglycemia. This may suggest that during the period of illness from a SARS-CoV-2 infection, patients' oral intake was unable to keep pace with the physiologic demands of the body. This is further supported by the association of a high BUN with non-severe CXR disease. A previous study looking at the association of hydration status with CXR findings of pneumonia revealed that improvement in hydration status resulted in worsening opacities on subsequent CXRs.7 This is an important finding as it illustrates the potential to misdiagnose vulnerable patients as not having COVID-19 pneumonia when, in fact, the disease may not be apparent and has the potential to rapidly progress. In addition to previously reported associations between a past medical history of renal disease and an elevated LDH with the presence of any COVID-19 lung findings on CXR, we also found that a past medical history of lung disease, O2 impairment, elevated respiratory rate, low albumin, and high ferritin on initial presentation to the hospital was associated with signs of COVID-19 on CXR (compared to no disease) and severe COVID-19 CXR disease.30., 31. Further, we are the first to show an association of increased comorbidity burden (CCI > 5) with non-severe CXR findings—a result that needs to be explored further as an increased CCI has been associated with increased mortality.20., 32. Therefore, CXR disease severity may not correlate with mortality risk in select populations. Future studies will need to evaluate the associations between patient demographics, clinical variables, COVID-19 lung disease burden quantified real-time on presentation CXR, and patient-centered outcomes such as mechanical ventilation and mortality. Our study has some limitations. Our approach used logistic regression which accounts for linear relationships between variables. While nonlinear interactions are common in models that analyze medical images our study did not focus on the analysis of medical images but instead focused on relationships between radiologist annotated features such as opacities and clinical characteristics, which in our patient population and other studies have been shown to exhibit mostly linear interactions29., 33., 34., 35.. The participants in this study were recruited from a single multihospital healthcare system and the data were analyzed retrospectively. Lung disease on CXRs were quantified by many radiologists, however, inter-reader variability was not evaluated. Further, the CXR was quantified in 4 discrete levels (i.e., negative, mild, moderate, severe) but was converted to binary outcomes, such as severe versus not severe and clear versus disease, that may be more clinically useful. However, the human eye cannot distinguish between the lung disease burden categories perfectly. Radiology experience was not collected or accounted for which is another limitation. The accuracy of Charlson Comorbidity Index is susceptible to a number of factors such as: possible ICD-10 coding errors and incomplete medical histories. Finally, research is needed to understand how real-time quantified lung disease burden can be adapted to be clinically useful for non–COVID-19 pulmonary disease. 5 Conclusion COVID-19 lung disease burden quantified in real-time on presentation CXR was characterized by clinical variables on thousands of patients. This novel approach to real-time lung disease burden collection can be adapted for real-time use in many lung diseases. We found that an absence of opacities in COVID-19 may be associated with poor oral intake and a prerenal state as evidenced by the association of clear CXRs with a low eGFR, hypernatremia, and hypoglycemia.. This important finding demonstrates the potential to misclassify severity of lung disease burden for vulnerable patients. Further, we provided evidence that a past medical history of lung disease, O2 impairment, elevated respiratory rate, low albumin, and high ferritin on initial presentation to the hospital was associated with signs of COVID-19 on CXR (compared to no disease) and severe COVID-19 CXR disease (compared to non-severe). Funding This work was supported by the 10.13039/100000049 National Institute on Aging of the 10.13039/100000002 National Institutes of Health [grant number R24AG064191]. The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication. This work was also supported by an STR seed grant and the 10.13039/100011976 Association of University Radiologists GE Radiology Research Academic Fellowship. Declaration of competing interest None. Appendix A Supplementary data Supplementary tables Image 1 Appendix A Supplementary data to this article can be found online at https://doi.org/10.1016/j.clinimag.2023.03.007. ==== Refs References 1. The Center for Systems Science and Engineering (CSSE) at Johns Hopkins University Coronavirus COVID-19 global cases center for systems science and engineering https://gisanddata.maps.arcgis.com/apps/opsdashboard/index.html#/bda7594740fd40299423467b48e9ecf6 2. Grasselli G. Tonetti T. Protti A. Pathophysiology of COVID-19-associated acute respiratory distress syndrome: a multicentre prospective observational study Lancet Respir Med 8 12 Dec 2020 1201 1208 10.1016/s2213-2600(20)30370-2 32861276 3. Bryce C. Grimes Z. Pujadas E. Pathophysiology of SARS-CoV-2: the Mount Sinai COVID-19 autopsy experience Mod Pathol 34 8 Aug 2021 1456 1467 10.1038/s41379-021-00793-y 33795830 4. Hare S.S. Tavare A.N. Dattani V. Validation of the British Society of Thoracic Imaging guidelines for COVID-19 chest radiograph reporting Clin Radiol 75 9 Sep 2020 10.1016/j.crad.2020.06.005 710.e9-710.e14 5. Hayden G.E. Wrenn K.W. Chest radiograph vs. computed tomography scan in the evaluation for pneumonia J Emerg Med 36 3 Apr 2009 266 270 10.1016/j.jemermed.2007.11.042 18571356 6. Jokerst C. Chung J.H. Ackman J.B. ACR appropriateness Criteria(®) acute respiratory illness in immunocompetent patients J Am Coll Radiol 15 11s Nov 2018 S240 s251 10.1016/j.jacr.2018.09.012 30392593 7. Hash R.B. Stephens J.L. Laurens M.B. Vogel R.L. The relationship between volume status, hydration, and radiographic findings in the diagnosis of community-acquired pneumonia J Fam Pract 49 9 Sep 2000 833 837 11032209 8. Au-Yong I. Higashi Y. Giannotti E. Chest radiograph scoring alone or combined with other risk scores for predicting outcomes in COVID-19 Radiology Sep 14 2021 210986 10.1148/radiol.2021210986 9. Cecchini S. Di Rosa M. Soraci L. Chest X-ray score and frailty as predictors of in-hospital mortality in older adults with COVID-19 J Clin Med 10 13 Jul 1 2021 10.3390/jcm10132965 10. Jiao Z. Choi J.W. Halsey K. Prognostication of patients with COVID-19 using artificial intelligence based on chest x-rays and clinical data: a retrospective study Lancet Digit Health 3 5 May 2021 e286 e294 10.1016/s2589-7500(21)00039-x 33773969 11. Kwon Y.J.F. Toussie D. Finkelstein M. Combining initial radiographs and clinical variables improves deep learning prognostication in patients with COVID-19 from the emergency department Radiol Artif Intell 3 2 Mar 2021 e200098 10.1148/ryai.2020200098 12. Razavian N. Major V.J. Sudarshan M. A validated, real-time prediction model for favorable outcomes in hospitalized COVID-19 patients NPJ Digit Med 3 2020 130 10.1038/s41746-020-00343-x 33083565 13. Shen B. Hoshmand-Kochi M. Abbasi A. Initial chest radiograph scores inform COVID-19 status, intensive care unit admission and need for mechanical ventilation Clin Radiol 76 6 Jun 2021 10.1016/j.crad.2021.02.005 473.e1-473.e7 14. Sukhija A. Mahajan M. Joshi P.C. Dsouza J. Seth N.D.N. Patil K.H. Radiographic findings in COVID-19: comparison between AI and radiologist Indian J Radiol Imaging 31 Suppl. 1 Jan 2021 S87 s93 10.4103/ijri.IJRI_777_20 33814766 15. Toussie D. Voutsinas N. Finkelstein M. Clinical and chest radiography features determine patient outcomes in young and middle-aged adults with COVID-19 Radiology 297 1 Oct 2020 E197 e206 10.1148/radiol.2020201754 32407255 16. Xiao N. Cooper J.G. Godbe J.M. Chest radiograph at admission predicts early intubation among inpatient COVID-19 patients Eur Radiol 31 5 May 2021 2825 2832 10.1007/s00330-020-07354-y 33051736 17. Kim L. Garg S. O'Halloran A. Risk factors for intensive care unit admission and in-hospital mortality among hospitalized adults identified through the US coronavirus disease 2019 (COVID-19)-associated hospitalization surveillance network (COVID-NET) Clin Infect Dis 72 9 2021 e206 e214 10.1093/cid/ciaa1012 32674114 18. Izcovich A. Ragusa M.A. Tortosa F. Prognostic factors for severity and mortality in patients infected with COVID-19: a systematic review PLoS One 15 11 2020 e0241955 10.1371/journal.pone.0241955 19. Petrilli C.M. Jones S.A. Yang J. Factors associated with hospital admission and critical illness among 5279 people with coronavirus disease 2019 in New York City: prospective cohort study BMJ 369 May 22 2020 m1966 10.1136/bmj.m1966 20. Cho S.I. Yoon S. Lee H.J. Impact of comorbidity burden on mortality in patients with COVID-19 using the Korean health insurance database Sci Rep 11 1 Mar 18 2021 6375 10.1038/s41598-021-85813-2 33737679 21. Deng F. Zhang L. Lyu L. Increased levels of ferritin on admission predicts intensive care unit mortality in patients with COVID-19 Med Clin (Barc) 156 7 Apr 9 2021 324 331 10.1016/j.medcli.2020.11.030 El incremento de ferritina sérica durante el ingreso predice la mortalidad de los pacientes de COVID-19 en Cuidados Intensivos 22. Garibaldi B.T. Fiksel J. Muschelli J. Patient trajectories among persons hospitalized for COVID-19: a cohort study Ann Intern Med 174 1 Jan 2021 33 41 10.7326/m20-3905 32960645 23. Hariyanto T.I. Japar K.V. Kwenandar F. Inflammatory and hematologic markers as predictors of severe outcomes in COVID-19 infection: a systematic review and meta-analysis Am J Emerg Med 41 Mar 2021 110 119 10.1016/j.ajem.2020.12.076 33418211 24. Martinez Mesa A. Cabrera César E. Martín-Montañez E. Acute lung injury biomarkers in the prediction of COVID-19 severity: total thiol, ferritin and lactate dehydrogenase Antioxidants (Basel) 10 8 Jul 29 2021 10.3390/antiox10081221 25. Yamamoto A. Wada H. Ichikawa Y. Evaluation of biomarkers of severity in patients with COVID-19 infection J Clin Med 10 17 Aug 24 2021 10.3390/jcm10173775 26. Warren M.A. Zhao Z. Koyama T. Severity scoring of lung oedema on the chest radiograph is associated with clinical outcomes in ARDS Thorax 73 9 2018 840 846 10.1136/thoraxjnl-2017-211280 29903755 27. Borghesi A. Maroldi R. COVID-19 outbreak in Italy: experimental chest X-ray scoring system for quantifying and monitoring disease progression Radiol Med 125 5 May 2020 509 513 10.1007/s11547-020-01200-3 32358689 28. Sadiq Z. Rana S. Mahfoud Z. Raoof A. Systematic review and meta-analysis of chest radiograph (CXR) findings in COVID-19 Clin Imaging 80 2021 229 238 10.1016/j.clinimag.2021.06.039 34364071 29. Vardhan A. Makhnevich A. Omprakash P. A radiographic, deep transfer learning framework, adapted to estimate lung opacities from chest x-rays Bioelectron Med 9 1 Jan 3 2023 1 10.1186/s42234-022-00103-0 36597113 30. Gatti M. Calandri M. Barba M. Baseline chest X-ray in coronavirus disease 19 (COVID-19) patients: association with clinical and laboratory data Radiol Med 125 12 Dec 2020 1271 1279 10.1007/s11547-020-01272-1 32894449 31. Abougazia A. Alnuaimi A. Mahran A. Chest X-ray findings in COVID-19 patients presenting to primary care during the peak of the first wave of the pandemic in Qatar: their association with clinical and laboratory findings Indian J Radiol Imaging 2021 2021 4496488 10.1155/2021/4496488 32. Sottile P.D. Albers D. DeWitt P.E. Real-time electronic health record mortality prediction during the COVID-19 pandemic: a prospective Cohort Study Jan 15 2021 medRxiv 10.1101/2021.01.14.21249793 33. Levy T.J. Coppa K. Cang J. Development and validation of self-monitoring auto-updating prognostic models of survival for hospitalized COVID-19 patients Nat Commun 13 1 Nov 10 2022 6812 10.1038/s41467-022-34646-2 36357420 34. Yadaw A.S. Li Y.C. Bose S. Iyengar R. Bunyavanich S. Pandey G. Clinical features of COVID-19 mortality: development and validation of a clinical prediction model Lancet Digit Health 2 10 Oct 2020 e516 e525 10.1016/s2589-7500(20)30217-x 32984797 35. Schwab P. DuMont Schütte A. Dietz B. Bauer S. Clinical predictive models for COVID-19: systematic study J Med Internet Res 22 10 Oct 6 2020 e21439 10.2196/21439
PMC010xxxxxx/PMC10015091.txt	==== Front Gov Inf Q Gov Inf Q Government Information Quarterly 0740-624X 0740-624X The Authors. Published by Elsevier Inc. S0740-624X(23)00015-1 10.1016/j.giq.2023.101815 101815 Article Digital government transformation as an organizational response to the COVID-19 pandemic Moser-Plautz Birgit a Schmidthuber Lisa b⁎ a University of Klagenfurt, Universitaetsstrasse 65-67, 9020 Klagenfurt am Woerthersee, Austria b WU Vienna University of Economics and Business, Welthandelsplatz 1, 1020 Vienna, Austria ⁎ Corresponding author. 15 3 2023 6 2023 15 3 2023 40 3 101815101815 18 8 2022 11 3 2023 12 3 2023 © 2023 The Authors 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Many public organizations struggle to adapt to digital transformation. Whereas previous research has identified internal drivers of change, an unpredictable factor from the external environment such as the COVID-19 pandemic can trigger public innovation. In this study, we aim to investigate if and how the COVID-19 pandemic has influenced the digital government transformation. In more detail, we explore how the COVID-19 pandemic has affected different organizational aspects that are expected to be affected by a digital transformation. Findings from case studies of ten organizations from the Austrian federal administration indicate that the pandemic has not only led to an increased use of technological means but also influenced various organizational aspects such as employees' attitudes toward technology and organizational culture toward innovation. In particular, organizations heavily affected by the pandemic have benefited from a greater degree of digital transformation. Consequently, the pandemic has influenced a spirit of innovation and accelerated the speed of digital transformation. Keywords Public innovation Crisis Digital transformation Federal Administration Digital technology ==== Body pmc1 Introduction The COVID-19 pandemic has enormously influenced the lives of individuals and organizations at the global level. Lockdowns and related social distancing measures have tremendously changed the working practices in almost all sectors. Many organizations asked their employees to work from home or had to reduce employees' working hours as production or service delivery was restricted due to social distancing measures. In crises such as pandemics, public authorities play a significant role in coordinating the response, minimizing the extent of damage, and enabling recovery (Boin, Hart, Stern, & Sundelius, 2016). The pandemic can be understood as an unpredictable factor from the external environment that has put pressure on organizations to change, like a sudden shock or a disaster (Danielsen, 2021; Gabryelczyk, 2020; Reina, Ventura, Cristofaro, & Vesperi, 2022). This factor has affected not just certain organizational levels or aspects but the organization as a whole. In many cases, the government's response to the pandemic was a digital one (Lee-Geiller, Lee, & David, 2022; Park, Richards, & Reedy, 2022; Polzer & Goncharenko, 2021; Wanckel, 2022). For example, citizens were requested to collaborate with the government to trace contacts via digital apps (Lin, Carter, & Liu, 2021), governments organized civic hackathons to face associated challenges together with citizens (Gama, 2021; Vermicelli, Cricelli, & Grimaldi, 2021), and social media apps were used to inform and engage citizens (Criado, Guevara-Gómez, & Villodre, 2020; Sandoval-Almazan & Valle-Cruz, 2021). Apart from that, public employees were asked to continue their tasks from home, which changed their working practices within a few days, resulting in significant consequences for public service delivery (Edelmann, Schossboeck, & Albrecht, 2021; Garcia-Contreras, Munoz-Chavez, Valle-Cruz, Ruvalcaba-Gomez, & Becerra-Santiago, 2021). Considering that service delivery in many public organizations is not as technologically advanced as in other service organizations, the sudden change in working practices has resulted in pressure to innovate and find new ways of organizing in a short period. Previous research identified external drivers as “the main motivation for organizational transformation” (Tangi, Janssen, Benedetti, & Noci, 2020), triggered by the pressure and sense of urgency to change. However, we lack an understanding of how crises drive innovation adoption in general (e.g., De Vries, Bekkers, & Tummers, 2016) and how the COVID-19 pandemic as an external factor has influenced the organizational transformation toward a digital government in particular. A digital government is related to “new styles of leadership, new decision-making processes, different ways of organizing and delivering services, and new concepts of citizenship” (Gil-Garcia, Dawes, & Pardo, 2018, p. 634). Accordingly, the use of modern information and communication technologies should not only improve the quality of service delivery but also stimulate citizen participation and increase government accountability through transparent information. Taking an organizational perspective, we aim to explore how the COVID-19 pandemic has influenced the digital government transformation and, therefore, investigate how organizations have responded to the COVID-19 pandemic. In more detail, we investigate different organizational aspects that are expected to be affected by a digital transformation. We thereby build on the digital transformation literature (Gil-Garcia & Flores-Zúñiga, 2020; Mergel, Edelmann, & Haug, 2019; Tangi, Janssen, Benedetti, & Noci, 2021) and argue that digital transformation does not only involve the implementation of digital technology but refers to changes in both the technical and social systems. Accordingly, we study government transformation as a holistic process that involves changes in all organizational aspects. Based on these results, we explore if and how the COVID-19 crisis has impacted the digital government transformation. To examine digital government transformation, we draw on the Austrian public sector and conduct ten case studies representing different organizations in the Austrian federal administration. Austria's response to the COVID-19 outbreak is particularly interesting to study, as the country was one of the “First Mover” countries that introduced strict measures relatively early (Shields, 2020). Due to a sharp increase in infected cases, a strict lockdown was introduced on March 16th, 2020, several weeks earlier than in many other European countries. Unlike in other federal countries, the Austrian federal government has taken a unified public health response due to epidemic laws prioritizing the central level in such circumstances (Czypionka & Reiss, 2021). At the same time, despite Austria's progress in digital transformation, several European countries outperform the country's digital performance (European Commission, 2022). Consequently, there is a need to advance toward a digital government. By understanding the influence of the pandemic on digital government transformation, we contribute threefold to previous literature: First, we contribute to research on governance in the digital age and the determinants of digital government transformation by illustrating how external pressure makes organizations transform (Gil-Garcia et al., 2018). Previous research has already investigated the factors explaining organizational transformation (Tangi, Janssen, Benedetti and Noci, 2020, Tangi, Janssen, Benedetti and Noci, 2021), and there are some first studies shedding light on the changes in a public organizational context attributed to the pandemic such as remote working practices (Garcia-Contreras et al., 2021; Reina et al., 2022) and their effects on organizational and digital culture (Edelmann et al., 2021). We contribute to this literature stream by exploring how the pandemic has caused changes in different organizational aspects. Second, we provide insights into the process of digital transformation projects using an organizational lens, thereby responding to a call by Mergel et al. (2019). We identify the organizational aspects that have been changed in response to the pandemic and investigate how the pandemic has influenced the progress made in digital government transformation (Gabryelczyk, 2020). In addition, by comparing the level of digital transformation in different Austrian organizations, we can analyze how the organizational context and environment affect the progress in digital transformation. From an analytical perspective, we thus explain the success of digital government by examining government organizational practices rather than citizens' adoption of digital government. Third, we provide empirical insights into the organizational responses to a crisis by studying different organizations of the Austrian public administration. The Austrian public administration is especially interesting, as Austria can be described as a Neo-Weberian state model of administration, which is characterized by the adoption of managerial elements and a performance orientation (Korac, Saliterer, Sicilia, & Steccolini, 2020). At the same time, the legalistic Rechtsstaat (« rule of law ») tradition with bureaucratic governance is of ongoing relevance (Leixnering, Schikowitz, & Meyer, 2016). While the implementation of management practices in the public sector is in accordance with the ideas of New Public Management (NPM), Austria is categorized as a “latecomer” in terms of NPM-type reforms (Polzer & Seiwald, 2021). Whereas the willingness to change can be considered contained within the context of Austrian public administration, it is particularly interesting to study innovative behavior in times of crisis. 2 Theoretical background Modern information and communication technologies provide new possibilities for government at different levels to innovate service delivery, intensify relationships with citizens, and integrate external actors in the co-production of public services (Ingrams, Kaufmann, & Jacobs, 2020; Mergel, 2015; Moon, 2020), resulting in the emergence of government digitalization at different degrees at the national and international level (Edelmann & Mergel, 2021; Gil-Garcia & Flores-Zúñiga, 2020; Ingrams, Manoharan, Schmidthuber, & Holzer, 2020). This transformation process triggered by the potential of digital technologies is summarized under the term “digital transformation.” At the organizational level, the transformation comprises reorganizing existing processes, procedures, structures, and services (Tangi et al., 2021). The concept of “digital transformation” has to be distinguished from the concept of “e-government,” as the transformation goes beyond adopting new technologies toward redesigning organizational aspects, including structures, operations, and the culture of government (Omar, Weerakkody, & Daowd, 2020; Tangi et al., 2021). Digital transformation involves a change in the technical system and changes in the social system involving cultural and organizational aspects (Mergel et al., 2019). Digital transformation is thus to be distinguished from digitization, in which switching from analog to digital services involves a 1:1 change in the delivery mode and the addition of a technological channel of delivery, and digitalization, i.e., “potential changes in the processes beyond mere digitizing of existing processes and forms” (Mergel et al., 2019, p. 12). The status of digital government greatly varies across countries (Ingrams, Manoharan, et al., 2020), within countries, and between departments (Gil-Garcia & Flores-Zúñiga, 2020). This indicates that the success of implementing digital government is multifactorial, as already shown by previous research (Gil-Garcia & Flores-Zúñiga, 2020). For example, managerial activities can drive the transformation of digital government (Tangi et al., 2021); political support improves the success of digital government projects (Danielsen, 2021); the availability of IT infrastructure facilitates the digitalization of information and services; and individuals' perception of the perceived usefulness and ease of use of the technology is decisive for technology adoption (Gil-Garcia & Flores-Zúñiga, 2020). Investigating the digital transformation process of Dutch public administration, Tangi et al. (2020) found that the main motivation for organizational transformation is external drivers such as external pressure, legal obligations, or expectations from external actors. In the Italian context, Tangi et al. (2021) highlighted the importance of support from politicians in organizational transformation, whereas cultural factors did not impact digital government transformation. Next to organizational characteristics and in line with the Technology Enactment Framework (Gil-Garcia, 2012), the organizational environment such as political, social, and economic conditions can affect government activities and institutional arrangements, which directly influence the success of digital government (Gil-Garcia & Flores-Zúñiga, 2020). In 2020, the coronavirus disease pressured governments worldwide at different levels to take measures (Eom & Lee, 2022; Kim, 2021; Polzer & Goncharenko, 2021). Several case studies have highlighted the significant role of digital governance in helping to meet these challenges (Lee, Lee, & Liu, 2021; Lee-Geiller et al., 2022). Beyond this necessity to respond to the crisis and find responses to urgent problems, we argue that this urgency in implementing digital solutions will likely have multiplier effects on different organizational aspects. In line with the comprehensive and integrative view of government transformation, digital transformation is not only characterized by adopting new technological tools but by a change throughout all organizational aspects (Gil-Garcia & Flores-Zúñiga, 2020; Tangi et al., 2021). Digital government transformation can thus be understood as “second-order organizational changes enabled by digital technologies transforming the way organizations are structured and organized and resulting in a new state, from the point of view of processes, culture, roles, relationships, and possibly all aspects of the organization” (Tangi et al., 2021, p. 2). While transformation is triggered by technological means, it also influences organizational and social elements, which is why we understand organizations as complex socio-technical systems (Bostrom & Heinen, 1977; Tangi et al., 2021). To capture the depth and width of digital government transformation, all elements that characterize digital transformation must be considered, so it is essential to cover changes in all these organizational aspects (Tangi et al., 2021). Table 1 gives an overview of the organizational aspects that are expected to be affected by a digital transformation (Eom & Lee, 2022; Gil-Garcia & Flores-Zúñiga, 2020; Mergel et al., 2019; Tangi et al., 2021; Vial, 2019). First, this concerns the tasks and processes that can be specified by the type, technology, and competencies needed to perform the task. Second, an individual such as a public employee, is responsible for carrying out the task. This person can be characterized by their attitudes toward the tasks, motivation to work, experience, and competencies. Third, the employee's work process is influenced by organizational resources and structures such as technological and financial resources and a strategy for digital transformation. Fourth, resource availability relates to organizational culture such as organizational regulations, relationships, and pressures.Table 1 Organizational aspects influenced by digital government transformation. Table 1Organizational aspects Definition Examples Tasks & Processes Characteristics of the tasks and processes Level of client interaction, level of standardization, type of task Individual Characteristics of the individual's duties and competences needed to perform the task Attitudes toward using technology, technological knowledge, experience with digital services Resources & Structures Characteristics of the organizational resources and structures available to perform the task Availability of infrastructure, management and political support, financial resources, strategy for digital transformation, system integration Culture Organizational regulations and values Communication within and between government units, leadership culture, internal pressure Sources: Gil-Garcia & Flores-Zúñiga, 2020; Tangi et al., 2021. 3 Research design To investigate the effects of the COVID-19 pandemic on digital government transformation, we conducted ten case studies representing different organizations in the Austrian federal administration. A case study approach allows for connecting theory and empirical evidence (Yin, 2009), where we can explore the phenomena that emerge from the data at hand and incorporate useful concepts from previous research. A multiple case study research approach (Eisenhardt, 1989; Yin, 2009) allows for comparing and contrasting the effects of the COVID-19 pandemic in the different cases against each other and against the theoretical background. We apply a qualitative research approach to obtain accounts from those experiencing the phenomenon of theoretical interest, thereby following an interpretive paradigm that focuses on subjective perceptions and meanings assigned to them by individuals (e.g., Kidd, 2002). 3.1 Research context The Austrian federal administration was chosen as a research context, which is an interesting case due to three reasons: First, the Austrian federal government has taken a significant role in responding to the pandemic (Czypionka & Reiss, 2021) and is also responsible for coordinating the digital transformation of the public sector. As the ten organizations are part of the Austrian federal administration, we refer to the characteristics of the Austrian federal administration. Second, as a “First Mover” country, Austria took early and strict COVID-19 measures (Shields, 2020). The COVID-19 situation in Austria is described in this section. Third, Austria has already progressed in digital transformation. However, several European countries especially recently outperformed the country's digital performance (European Commission, 2022), which illustrates the need to advance toward a digital government. 3.1.1 Characteristics of the Austrian federal administration According to the Austrian constitution, Austria is a federal state. The federal government is in charge of the judicial system, responsible for the police and military, and in control of public accounts and the administration of public funds on all levels of government (Bußjäger & Schramek, 2020). The nine state governments (Vienna is both state and local government) exercise power within their own legislative and administrative autonomy and on behalf of the federal government (Hammerschmid & Meyer, 2005). More than 361,000 employees (full-time equivalent) are working at the federal (135,840), state (146,695), or local (78,865) government level (BMKÖS, 2022), which is about 17% of total employment. The Austrian public administration is challenged by demographic change, as more than 35% of central government employees are 55 years of age or older and thus will retire within the next 10 years (OECD, 2021). 3.1.2 COVID-19 situation in Austria As was the case with other European countries, Austria was affected by the coronavirus from March 2020 onwards. As illustrated in the online supplementary material, the first confirmed COVID-19 case was reported in Austria at the end of February 2020. In mid-March 2020, the Austrian government introduced the first lockdown measures, including restrictions on outdoor activities, social distancing measures, and recommendations for telework. First shops were reopened in mid-April, and measures were eased in mid-May. Summer 2020, with a few cases, was followed by the second wave, with a sharp increase in infections in autumn 2020. Consequently, the government has introduced several measures over the winter months. At the start of 2021, citizens were offered a free COVID-19 vaccination, which was accepted in the beginning. However, the vaccination rate stagnated at around 60% in the summer of 2021. In addition to the vaccination campaign, the Austrian government extended the offer to be tested for COVID-19. Citizens could test regularly and free of charge using both anti-gene and PCR (polymerase chain reaction) tests until spring 2022, when the offer was restricted to a certain number of free monthly tests. Using the green pass app, individuals needed to show their test, vaccination, or recovery certificates when entering a restaurant or their workplace (from November 2021 to March 2022). Additional information on the COVID-19 situation in Austria and details on the number of confirmed COVID-19 cases over time are illustrated in the online supplementary material. 3.1.3 Status of digital government in Austria Austria is ranked 15th in the 2020 E-Government Development Index of the United Nations (United Nations, 2020) and 6th among 36 European countries according to the eGovernment Benchmark (European Commission, 2021). Austria is described as a country where citizens and businesses can complete almost all public services online and rarely need to visit a government building (European Commission, 2021). “Digital public services” is the Digital Economy and Society Index (DESI) dimension that Austria performs best in and ranks 10th among EU countries (European Commission, 2022). The Austrian federal administration has an official web portal (österreich.gv.at), which is an interagency platform where citizens can find information on administrative topics and complete selected public services online. Another platform, particularly for businesses, is the Business Service Portal (usp.gv.at), and one for financial administration services is the “FinanzOnline” portal (see also Edelmann & Mergel, 2021; Scholta, Mertens, Kowalkiewicz, & Becker, 2019). Responsible for digital government is the Federal Ministry for Digital and Economic Affairs (responsibilities changed mid-2022), which cooperates with different actors and groups such as the BRZ (Austrian Federal Computing Center, a privatized IT service provider), Chief Digitalization Officers Taskforce (installed in every ministry), coordination boards for digital administration, and DIA (digitalization agency). 3.2 Case description We conducted ten case studies of organizations in the Austrian federal administration. For choosing the ten organizations, we followed a polar-type approach where extreme cases were selected. Thus, the cases are useful for illuminating changes in different organizational aspects, and we expected a contribution to our research aim (e.g., Eisenhardt & Graebner, 2007). Organizations were selected based on their varying involvement or roles during the pandemic, differing number of services for stakeholders, and differing levels of face-to-face contact. Table 2 provides an overview of the organizations analyzed, their organizational characteristics, and the extent to which they were affected by the pandemic. In analyzing how the COVID-19 pandemic influences different organizational aspects, we first have to understand the context of these organizations, as situational opportunities and constraints “affect the occurrence and meaning of organizational behavior as well as the functional relationships between variables” (Johns, 2006, p. 386).Table 2 Overview on case studies. Table 2Case Name of the organization Organizational characteristics (pre-COVID) Role during pandemic Infrastructure Telework culture Services to stakeholders Face-to-face contact with stakeholders A Federal Chancellery On-site Uncommon Low Low Citizen-government communication; COVID vaccination B Federal Ministry for Climate Action, Environment, Energy, Mobility, Innovation and Technology Partly mobile Common Low Low Special regulations in terms of traffic C Federal Ministry for Digital and Economic Affairs Partly mobile Uncommon Intermediate (responsible for offering e-services) Low Supporting businesses D Federal Ministry of Education, Science and Research On-Site (Education)/ mobile (Science and Research) Partly common (in central administration) High High COVID-related measures in schools; corona bonus E Federal Ministry of Finance Mobile Uncommon High Intermediate COVID-related benefits for businesses (‘Ausfallbonus’, ‘Corona Hilfsfonds’) F Federal Ministry of Interior Mobile (police), on-site (central administration) Pilot project High High Police to control measures; demonstrations; entry regulations G Federal Ministry of Labour Partly mobile Uncommon Low Low High number of unemployed, COVID-related short-time working H Public Employment Service Partly mobile Uncommon High High Registering high number of unemployed people; Registering COVID-related short-time working (‘Kurzarbeit’) I Federal Ministry of Social Affairs, Health, Care and Consumer Protection Mobile (social affairs), on-site (health care) Partly common Intermediate Low Reporting of COVID infections, COVID-related measures, COVID anti-gene and PCR test infrastructure, COVID vaccination, contact tracing, mask mandate, vaccine mandate, bonus for health workers J Austrian Court of Audit Mobile Common Low Low Providing information on as well as auditing of financial aid measures Sources: Websites of the ministries and organizations, Interview data. The external context refers to political and environmental variables such as a pandemic that is related to political decisions (Mergel, 2019). The ten cases, however, vary in the degree to which they were responsible for facing challenges and being affected by the pandemic. The Federal Chancellery (Case A) communicated COVID-related topics to citizens and coordinated the vaccination campaign. The Federal Ministry for Climate Action, Environment, Energy, Mobility, Innovation and Technology (Case B) was working partly remotely already before the pandemic and was responsible for developing specific COVID-related regulations in terms of traffic. The Federal Ministry for Digital and Economic Affairs (Case C) was supporting businesses in facing the challenges related to the pandemic, and the Federal Ministry of Finance (Case E) was dealing with COVID-related benefits for businesses. The Federal Ministry of Education, Science and Research (Case D) organized measures for schools and educational institutions. The Federal Ministry of Interior (Case F) and the police were concerned with controlling citizens' adherence to rules and standards. Furthermore, the increasing workload of the police was also related to the high number of demonstrations against COVID-related measures and vaccination policies. The Federal Ministry of Labour (Case G) was confronted with a large volume of unemployed people and had to register for COVID-related short-time work (“Kurzarbeit”). Especially the Federal Ministry of Social Affairs, Health, Care and Consumer Protection (Case I) and the Public Employment Service (Case H) were greatly involved in organizing measures to protect individuals from health risks and unemployment. Finally, the Austrian Court of Audit (Case J) that was used to remote work was responsible for providing information and auditing financial aid measures. Next to the organizations' role in tackling the challenges of the pandemic, we provide some more internally contextual information on the organizations' infrastructure, telework culture, number of services to stakeholders, and degree of face-to-face contact with stakeholders in Table 2 (additional information on the cases can be found in online supplementary material). Although telework was already possible pre-COVID according to public service law, it was only used by a small proportion of employees (Gabmayer, Dohnal, & Luczensky, 2019), which is also reflected in the interview data regarding telework culture. 3.3 Data collection The case studies are built on document analysis and semi-structured interviews with 17 public managers (such as Chief Information Officers, Chief Digitalization Officers, and department heads) in the selected case organizations, one representative of the Federal Ministry for Arts, Culture, the Civil Service and Sport, and one representative of a privatized IT service provider who have expertise and experience in the area of digitalization at the federal administration level. In total, 19 interviews were conducted. The interviewees are highly knowledgeable informants with positions at higher levels of the hierarchy “who view the focal phenomena from diverse perspectives” (Eisenhardt & Graebner, 2007, p. 28) and are thus able to provide a comprehensive overview of the topic. The five interviewees of the Federal Ministry for Digital and Economic Affairs, in particular, provided information not only about their own ministry but about all ministries since they were involved in the formulation and implementation of digitalization projects in the whole federal administration. Information about the federal administration as a whole was also provided by the interviewees of the Federal Ministry for Arts, Culture, the Civil Service and Sport, the privatized IT service provider, and the Austrian Court of Audit. This allowed not only to get the view from inside the respective case organization and the outside perspective but also to cross-check the answers given by interviewees (Eisenhardt & Graebner, 2007; Yin, 2009). Potential interviewees were identified through directories on the websites of the respective departments and were contacted by email. The head of the department was asked first since, in most cases, approval must be given by this official anyway. In some cases, the head of the department was available for an interview; in others, a team member was referred to. To identify further experts within the federal administration, snowball techniques (Biernacki & Waldorf, 1981) were used, i.e., respondents were asked for other people they knew who could provide information on the questions posed. The interviews with the 19 experts were conducted in German using online video tools (Zoom and Skype for Business) between July and November 2021 and lasted, on average, 44 min. The open-ended questions were derived from the literature in the field (e.g., Clement, Esposito, & Crutzen, 2022; De Vries et al., 2016; Fischer, Heuberger, & Heine, 2021; Mergel et al., 2019), and following the aim of this study, they covered the effects of the COVID-19 pandemic on digital government transformation. First, more generic questions about the interviewee and the respective organization were asked, followed by questions regarding drivers and barriers to digitalization. After going into more detail about the effects of the COVID-19 pandemic on, e.g., barriers, objects, and digitalization strategy, as well as if digital solutions were used to solve problems caused by the COVID-19 pandemic, the questionnaire ended with questions regarding the future of a digitally transformed public sector (the full questionnaire can be found in the supplementary materials). In addition, field notes were made for each interview to capture any impression that emerged during the conversation; this overlap of data collection with data analysis allowed us to add questions to following interviews for cross-checking answers and obtaining more insights when necessary (Eisenhardt, 1989). An informed consent form was signed by the interviewer and the interviewee beforehand, with information on the purpose of the study, data protection, and confidentiality, declaring that the actual identity of the interviewee would not be revealed. The interviews are blended with data collected online—articles in newspapers and news and blogs on government websites. This included reports and strategy documents like the digitalization report and the digital action plan for Austria from the website Digital Austria for information on the overall federal administration but also documents from the specific case organizations such as the “8-Point Plan for Digital Learning” from the website of the Federal Ministry of Education, Science and Research. In addition to interviewing experts in different positions, the triangulation of primary and secondary data helped build the cases from different perspectives. 3.4 Data coding and analytical method With the permission of the interviewees, all interviews were recorded, full transcriptions were produced, and they were coded using MAXQDA qualitative analysis software. Our method was a qualitative content analysis of the interview transcripts; therefore, the coding scheme was derived from the theoretical background following a deductive approach (Mayring, 2014). We chose a deductive approach, since there is relevant previous research on digital transformation (e.g., Mergel et al., 2019), digital government, and organizations as complex socio-technical systems (e.g., Tangi et al., 2021) that can be used to operationalize our research aim into categories. Consequently, we followed the steps of deductive category assignment (Mayring, 2014) and defined the main categories and subcategories prior to the analysis based on the theoretical background and previous literature. The main categories are the organizational aspects that can be influenced by digital government transformation (i.e., tasks and processes; individuals; resources and structures; and culture), for which we have derived subcategories based on previous literature. In order to capture the progression of the categories, a simple scale with two values (change, no change) and three values (more/increased, less/decreased, the same) for every subcategory was developed. After a material run-through and preliminary coding of half of the transcripts, we discussed and revised the coding scheme; since we started with very detailed subcategories, we merged some of them and, where necessary, specified coding rules for an unambiguous assignment to a particular subcategory. The final coding scheme with example quotes was used to code all transcripts and is presented in the online supplementary material, with the literature from which we derived the code. For consistency, each transcript was coded by two researchers; the coding was discussed, and an agreement on the codes were reached. In total, 33 codes and 481 codings related to the theoretical background were defined. 4 Findings The findings of our case study analyses are presented as follows: In the first part of the section, we provide an overview of the results on how the pandemic has influenced the different organizational aspects (i.e., tasks and processes, individuals, resources and structures, and culture). In the second part of this section, we aggregate these level-specific findings and conclude the degree of digital transformation of the ten organizations that the COVID-19 pandemic has impacted. 4.1 Case analysis 4.1.1 Tasks and processes Following the theoretical background, we assessed the role of the COVID-19 pandemic in digitalizing tasks and processes. The first factor we examined was the use of technological means, i.e., the level of digitalization. Although some emphasized that the employees had already always worked digitally, with the exception of one interviewee, all agreed that the use of technological means and the level of digitalization in performing tasks and processes increased during the pandemic. Due to the pandemic, this digitalization of tasks and processes led to the reengineering of existing processes and was less of a 1:1 translation of analog to digital ones. To implement certain tasks and processes to fight the pandemic, collaboration between different levels of government increased but also posed a barrier to implementation. Also, the level of standardization increased when it came to using communication tools. The pandemic caused an increase in the duration or frequency of certain tasks related to fighting the pandemic, e.g., monitoring systems for COVID-19 cases and financial support for families, where the organizations applied digital technologies to process the high number of applications.But yes, that was also one of the things that was quite deliberately initiated by Corona, that is, that work was done here with comprehensive tools and very modern approaches to artificial intelligence in order to achieve rapid results so that the people who really urgently needed the money in this phase could have their applications processed positively as quickly as possible. (Case G, Federal Ministry of Labour; Interviewee 3). Furthermore, a digital identity (“Handy-Signatur”) was required to access the green pass. Due to the high frequency of the task and the increasing level of client interaction, chatbots were implemented to help citizens with their inquiries. The level of client interaction decreased in areas that were characterized by a lot of face-to-face contact before the pandemic, e.g., applying for unemployment benefits. These processes were handled online during the pandemic through email or the online portal (e-AMS). As the complexity of the task increased in some cases, applying digital tools, e.g., artificial intelligence to knowledge management or combining different register data in the background to provide applications like the mobile phone signature, was necessary. In most cases, task accomplishment was perceived as unchanged, with some exceptions, e.g., one interviewee perceived the output of the employees as higher while they were working from home, while another highlighted that those tasks where someone had to be in the office, e.g., reconstruction, were delayed. Skills and competencies to perform the task did increase. This relates to the proper use of video conferences and, thereby, different codes of behavior (e.g., not whispering with colleagues so that those online cannot hear them) and how to collaborate and lead via video conferences and at a distance. In addition, different online courses were offered to increase digital competencies. 4.1.2 Individual On an individual level, job satisfaction and motivation increased as employees experienced that digital tools functioned well, as well as because employees were highly motivated to avoid going to the office due to a computer problem. Some interviewees indicated that particularly those areas and departments, which already performed well before the pandemic, got an extra motivation boost.In other words, the pandemic did not drive us into innovation; the pandemic activated the resources we already had and, with an incredible activation also of intrinsic motivations, drove employees forward. (Expert from the Federal Ministry for Arts, Culture, the Civil Service and Sport; Interviewee 16). Most interviewees noted that as their experience with digital services increased, they learned about the well-functioning tools that exist, particularly in the area of digital collaboration and communication. Other interviewees also emphasized that employees were forced to work with digital tools. With this experience, their technological knowledge also increased in most cases. Some areas, e.g., the police, were used to working remotely and with digital tools. For them, technological knowledge did not change due to the pandemic. When it comes to perceived risks and barriers, they are twofold: On the one hand, most interviewees reported that perceived barriers to adopting digital tools decreased as employees lost their fear of using digital tools.[…] I think people have understood that the opportunities it [digitalization] offers far outweigh what might once have been seen as a danger. I think that understanding has set in, yes. (Case C, Federal Ministry for Digital and Economic Affairs; Interviewee 6). Only one interviewee reported that the problems and challenges did not change. But another interesting aspect that an interviewee mentioned was that the pandemic made employees claim digitalization. This, however, also means that those incapable of using digital tools are increasing under pressure, and their fear has increased enormously. On the other hand, risk awareness for cyber security and information security increased among employees. They learned that connecting their laptop to any public network and sharing content in video calls is different from meeting people in person.[…] that one becomes clearly more aware of the dangers, where perhaps before the focus was not on it. (Case C, Federal Ministry for Digital and Economic Affairs; Interviewee 6). Changes in the perceived ease of use were mentioned only rarely by the interviewees. Two mentioned that employees liked that tasks were getting easier, faster, and more efficient. In contrast, perceived usefulness was mentioned by almost all interviewees, as they observed a change in perception among the employees in almost all cases (except for two, where interviewees did not mention this aspect). So, by being forced to work remotely,[…] you've seen how much is actually possible and works online or remotely because you might not even be aware in the office of what's already being done electronically. (Case F, Federal Ministry of Interior; Interviewee 13). And that has led to a change in the mindset regarding digitalization as useful for the employees, as one interviewee emphasized:The pandemic has triggered a change in the mindset of many people, and many aspects have been understood and implemented more quickly than would otherwise have been the case. (Case G, Federal Ministry of Labour; Interviewee 3) 4.1.3 Resources and structures While one interviewee mentioned that the number of services and products increased constantly and was less triggered by the pandemic, many others brought up examples of internal services (e.g., digital communication, monitoring systems for COVID-19 cases, or dashboards) and external services (e.g., the green pass or financial support for families) implemented due to COVID-19. At the same time, the number of people working in the IT organization remained broadly unchanged during the pandemic due to the natural fluctuation, except in two cases where they formed an expert team for video conferences to ensure online communication for the ministers. Some interviewees reported that political support for digitalization increased during the pandemic. Politicians were aware of the necessity of investing in IT infrastructure for internal applications, but the focus was not on newer technologies. In addition, the parliament was keen to monitor data protection during the pandemic. However, the increased public awareness of technological failure by the state made political decision-makers more risk-averse, as one interviewee highlighted. When it comes to financial resources, interviewees reported that partly more budget became available to modernize and keep operating during the pandemic.Corona has certainly enabled us to expand our digital services even further, and we have also been given the budget to do so. (Case C, Federal Ministry for Digital and Economic Affairs; Interviewee 7). Not all organizations have a written strategy for digital transformation, but some at least have a plan or roadmap. These strategies were partly affected by COVID-19 as priorities have changed; only in two cases were no effects perceived by the interviewees. On the one side, less time was available for not immediately necessary projects, which resulted in a delay. On the other hand, the adoption, implementation, or concretization of other projects important during the pandemic were accelerated.The strategy is always based on this [government program], and it is also very flexible, changes, of course, and must be able to adapt. And it's quite clear that this digitalization boom, which Corona has now triggered, is now accelerating many products if I can describe it that way. (Case C, Federal Ministry for Digital and Economic Affairs; Interviewee 7). In all cases, interviewees reported that more technology was available to their organizations. This was mainly triggered by teleworking, which meant that employees needed to work remotely and organizations had to provide laptops, mobile phones, and software for video conferences. This shift toward mobile workplaces with docking stations was related to a procurement challenge:So, that was one of the big challenges, making people ready for mobile work and also equipping them with correspondingly IT-secure devices. (Case I, Federal Ministry of Social Affairs, Health, Care and Consumer Protection; Interviewee 15). Nevertheless, the situation remained unchanged in areas of newer technologies (artificial intelligence, robotics) or for departments or organizations with laptops and licenses for video conferences before the pandemic. Furthermore, institutional arrangements, particularly laws and regulations, have changed to enable teleworking or offering services online. As a country governed by the rule of law, every management change taking place necessitates a legal change; thus, interviewees reported that, e.g., the public service law was changed quite quickly to allow working from home. The aspects of system integration were only rarely mentioned by interviewees. They stated that new infrastructure (laptops and mobile phones) needed to be integrated into the existing architecture, video conferences needed to be hosted constantly and with different systems, and data architecture in the background was needed to set up processes. 4.1.4 Culture Pressure from inside (from employees) to digitalize increased. An interviewee reported that there was a high interest in digitalizing additional processes. Furthermore, interviewees reported that the organizational culture became more innovative:And I would say that the Austrian federal administration is a tanker, a really ponderous tanker, in which innovations are initiated at some point through the laborious, repeated turning of the wheel and only really become apparent at some point very, very late. The pandemic has already acted as a trigger here that has led to a change in mindset on the part of many people, and many aspects have simply been understood and implemented more quickly than would otherwise have been the case. (Case G, Federal Ministry of Labour; Interviewee 3). Due to remote work, the communication within and between administrative units has changed. As interviewees emphasized, most changes due to the pandemic occurred in digital communication and collaboration, but the administration started collaborating remotely.[…] we now conduct hybrid meetings as standard, and I believe that this is very positive. And especially in an environment that has grown historically like the public sector, this is a change that has happened in a relatively short time […] (Case C, Federal Ministry for Digital and Economic Affairs; Interviewee 6). Also, communication with stakeholders has changed in some areas, as video conference tools and chatbots were used for interaction. Additionally, a real change to the digital opening hours for the public was discussed. Interviewees perceived pressure from the public as expectations for faster implementation of digital services have increased. An example is the green pass app, accessible through a mobile phone signature. While the demand for this tool increased rapidly, citizens started to show interest in other digital services as stated here:And that helps us a lot, which is, of course, a driver in digitization, that people have found all these e-government services via the green pass. (Case C, Federal Ministry for Digital and Economic Affairs; Interviewee 7). Yet, with increased demand comes an increased awareness of the public and its critical eye. In offering the green pass, interviewees perceived that small technical malfunctions were scandalized and considered a failure of the state in digitalization efforts. When it comes to information security, interviewees indicated that working remotely and holding video conferences was a challenge at the beginning of the pandemic. In addition to an increased awareness of information security among employees, from a technical perspective, the organizations were able to get safe systems to connect laptops and safe video conference tools conforming to the general data protection regulation (GDPR). Regulations such as government-wide standardization of solutions for digital information and services have slowly increased, and the pandemic has highlighted the need for IT consolidation in the federal administration. 4.2 Case evaluation Table 3 provides a summary of findings and indicates whether and how these organizational aspects have changed since March 2020, the start of the COVID-19 pandemic in Austria. Based on the interviews, subcategories were classified as change or no change to represent increase/decrease or no change, respectively. In some cases, for example, interviewees reported that one aspect of a subcategory changed while another did not, which is indicated as a change or no change in Table 3. The aggregation of the findings allows one to assess the level of digital government transformation caused by the COVID-19 pandemic. We distinguish between four levels of digital government transformation: A low level of digital transformation is defined as changes in single elements of a few organizational aspects only. A medium level points to changes in a few elements of a few organizational aspects, whereas a high level refers to changes in elements of all organizational aspects. An advanced level of digital transformation refers to changes in all organizational aspects.Table 3 Summary of findings. Table 3Organizational Aspects / Code J B E I A C D F G H Digital government transformation Low Medium Medium Medium High High High High High High Tasks & Processes Complexity Increase Increase Increase Client interaction Increase Decrease Decrease Collaboration with others necessary Duration/frequency Increase Increase Increase Level of standarization Increase Reengineering of the existing processes Change/no change Change/no change Change/no change Change Change/no change Change Change Change Change/no change Task accomplishement No change No change No change No change No change Increase No change Level of digitalization Increase Increase Increase Increase Increase Increase Increase Increase/no change Increase Increase Skills and competences necessary to perform the task Increase Increase Increase Individual Perceived usefulness Increase Increase Increase Increase Increase Increase Increase Increase Perceived ease of use No change Increase Increase Increase Perceived risks and barriers Decrease Decrease Increase/decrease/no change Increase/decrease/ no change Decrease Increase/decrease Increase Decrease Technological knowledge Increase Increase Increase Increase Increase Increase Increase/no change Increase Increase Experience with digital services Increase Increase Increase Increase Increase Increase/no change Increase Increase Motivation Increase Increase Increase Increase Resources & Structures Availability of technology to an organization Increase/no change Increase/no change Increase/no change Increase/no change Increase/no change Increase/no change Increase/no change Increase/no change Increase Increase Management support Increase Increase Decrease Political support No change Increase Decrease Increase/decrease Increase Financial resources Increase Increase Increase Increase Increase System integration Change Change Change Strategy for digital transformation Change No change No change Change/no change Change/no change Change Change Change/no change Change/no change Change People working in the IT organization Increase No change Increase No change No change No change No change Number of services/products offered Increase Increase Increase Increase No change Increase Increase Institutional arrangements Change Change Change Change/no change Change Change Culture Regulations No change Increase Increase/no change Communication within and between government units Change Change Change Change Change Change Change Communication with stakeholder Change Change Change Change/no change Change Leadership Change Change Change Change Understanding of employees' / citizens' roles Information security Increase Increase/decrease Increase/decrease/no change Increase Increase Increase/decrease Increase Perceived internal pressure Increase Increase Perceived external pressure Increase Increase Increase Increase Innovative organizational culture Change Change Change Change Change Change In general, all organizations experienced a certain level of digital transformation during the pandemic. Organizations can be divided into three groups based on maturity levels: One organization experienced a low level of digital transformation characterized by changes in individual skills and competencies, resources, and communication channels only. In this organization, mobile infrastructure was already available, and a teleworking culture was established, combined with a low degree of face-to-face services (Case J, Austrian Court of Audit). The pandemic has initiated a medium-scale digital transformation in three organizations (Cases B, E, and I), including major changes in individual attitudes, resources, and structure. These organizations had at least partly a mobile infrastructure, and some had an established telework culture pre-COVID (Cases I, Federal Ministry of Social Affairs, Health, Care and Consumer Protection, and B, Federal Ministry for Climate Action, Environment, Energy, Mobility, Innovation and Technology). However, they offered only a low to intermediate number of face-to-face services, either because they offered a low number of services in general or because their services were available online (e.g., Case E, Federal Ministry of Finance). These differences might explain why the three cases in this group do not show any patterns in terms of changes in the organizational aspects. For example, three different levels of change in terms of resources and structures are observed, which might relate to the differences in mobile infrastructure, telework culture, and the number of face-to-face services pre-COVID. Finally, six organizations generated a high level of digital transformation described by partial changes in all four organizational aspects. Comparing these findings with the characteristics of sample organizations pre-COVID shows that although those organizations (Cases A, C, D, F, G, and H) had a partly mobile infrastructure, a teleworking culture was not established, and the degree of face-to-face services was high. All six organizations in this group show advanced levels of change at the individual level and some changes with regard to resources and structures. In general, organizations show varying changes with regard to organizational aspects of culture as well as tasks and processes. Apart from that, there is no advanced level of digital government transformation in any of the analyzed organizations. Thus, organizations that were used to providing several services and a high degree of face-to-face contact with different groups of stakeholders have experienced a high level of digital transformation. Also, cases with a low degree of face-to-face contact with stakeholders show a high level of digital transformation when they did not have a complete telework infrastructure and an established telework culture and were highly involved in fighting the pandemic. For example, the Federal Ministry for Digital and Economic Affairs (Case C) was responsible for the digitalization of the administration, and the Federal Ministry of Labour (Case G) was responsible for the labor market during the pandemic. These two cases also reported increased complexity and duration/frequency of tasks and processes. While other cases with almost complete telework infrastructure (Cases E and J) and/or an established telework culture (Cases B, I, and J) show a low to medium digital transformation during the pandemic. This indicates that the urgency of adapting to the new situation has triggered public innovation. 5 Discussion and implications 5.1 Discussion This study aims to understand the digital transformation of organizations in the Austrian federal administration during the COVID-19 pandemic and comes up with three key findings: First, the COVID-19 pandemic has impacted the digital transformation of organizations to a different extent. The pandemic has influenced a high level of digital transformation in six of ten organizations. Consequently, this study shows that an unpredictable factor from the external environment has accelerated the speed of organizational change toward digital government in several organizations of the federal administration (Danielsen, 2021; Gabryelczyk, 2020; Reina et al., 2022; Tangi et al., 2020). Although the pandemic has impacted digital transformation, no advanced level of digital transformation can be observed. This may be explained by the time required to reorganize existing processes, procedures, structures, and services (Tangi et al., 2021) and finally move toward an advanced level of transformation. Beyond that, digital government encompasses changes in the technical system and in the social system (Mergel et al., 2019). However, both systems were constrained during the time of the pandemic. Providing adequate resources was restricted by supply shortages, and introducing a new organizational culture was restricted by staff shortages due to, e.g., sick or care leave. Second, the pandemic has impacted different organizational aspects. Accordingly, the external pressure to change has translated to an increase in the level of digitalization (see Mergel et al., 2019). Beyond that, however, the perceived urgency has also influenced the individual level so that technological knowledge and the perceived usefulness of leveraging technology have increased, whereas perceived risks and barriers have been lowered. Furthermore, substantive changes are found in terms of resources and structures such as the availability of technology and a strategy for digital transformation. Consequently, the pandemic seems to have initiated a more holistic change. This could be due to the increased awareness of the benefits and the dependence on technological means in society during social distancing. Public administrators did not have to convince their employees to adopt a new digital way of working; instead, using innovative technological tools was the only way to communicate and complete tasks—both in the office and at home. Consequently, the pandemic has triggered organizations to overcome structural barriers such as financial resources and technological infrastructure and resources, and cultural barriers such as a lack of awareness about the value of a digital government (Wilson & Mergel, 2022). Third, organizations show varying degrees of digital transformation during the crisis, depending on their pre-COVID organizational characteristics and responsibilities. Those organizations that were greatly affected by the pandemic in their face-to-face service delivery showed a high level of digital government transformation during the crisis. For example, in Case D, the Federal Ministry of Education, Science and Research has already partly implemented mobile infrastructure and established a teleworking culture. However, their face-to-face service delivery was highly affected by the pandemic (school closure). In contrast, organizations with many services but a lower degree of face-to-face contact due to offering e-services report only medium digital transformation (e.g., Case E, the Federal Ministry of Finance). However, even those organizations with few face-to-face services show a high degree of digital transformation when they have little telework infrastructure and culture and are involved in crisis management (e.g., Case A, the Federal Chancellery). Consequently, the urgency to adapt due to organizational responsibilities put pressure on the ministries and accelerated the speed of digital transformation. 5.2 Implications This study has several implications for research on digital government transformation and public innovation in general. First, we added qualitative evidence on the effect of environmental conditions as an explaining factor for the success of digital government. Previous research has focused on the internal drivers of change and identified the factors stimulating or hindering organizational change (e.g., Wilson & Mergel, 2022). For example, we know from research on technology acceptance that employees' perceptions of usefulness, ease of use, and risks significantly influence the use of technological means (Gil-Garcia & Flores-Zúñiga, 2020; Oschinsky, Stelter, & Niehaves, 2021). In contrast, this study shows how the pandemic, as a sudden exogenous shock, has triggered an organizational change. To be more specific, we have analyzed ten organizations that share a similar external context (i.e., the COVID-19 pandemic) but vary in terms of organizational context characteristics and their specific role during the pandemic. Findings indicate that the more the organization was affected by the pandemic, the greater the transformation toward digital government, lending support to previous literature on the significant influence of different environmental variables on digital government success (Gil-Garcia & Flores-Zúñiga, 2020; Ingrams, Manoharan, et al., 2020; Tangi et al., 2020). These external pressures have then triggered a change regarding internal organizational aspects. Building on the literature on public organizations' adoption of digital technology (Gil-Garcia & Flores-Zúñiga, 2020; Tangi et al., 2021), we found that the pandemic has not only affected the mode of working due to social distancing measures but has influenced all organizational aspects by different degrees. Consequently, existing processes were not just translated from analog to digital, but a change involving organizational aspects such as tasks and processes, individual employees, resources and structures, and organizational culture has been triggered (Gabryelczyk, 2020). While previous research has shown that digital technology changes the technical system of the organization before the social system (Tangi et al., 2020), our findings indicate that the pandemic has influenced both systems to some degree, meaning that organizations have moved beyond the digitization of services and the digitalization of processes (see Mergel et al., 2019). Despite the fact that technologies are used for providing information, communicating, and collaborating more intensively, findings do not indicate a digital transformation toward AI-augmented public administration (Ahn & Chen, 2022). Second, this study contributes to the literature on organizational responses to a crisis (Comfort, Yeo, & Scheinert, 2019; Eom & Lee, 2022; Phillips, Roehrich, & Kapletia, 2021). The pandemic has suddenly shocked a sector that is known for a culture of risk aversion and resistance to change (De Vries et al., 2016; Feiock, Lee, Park, & Lee, 2010), resource constraints, and small innovation budgets (Borins, 2001). The COVID-19 pandemic, as a high-velocity situation, has led to organizational changes in digital practices. For example, there was a virtually immediate increase in the use of digital technology, which facilitated the production and dissemination of information and coordination among organizations and citizens. Digital transformation was especially prevalent in organizations greatly affected by the pandemic and those offering several services to stakeholders or those without a teleworking culture. Consequently, both the urgency and feasibility of using digital technology have influenced the digital government transformation of the Austrian federal administration. The crisis thus seems to not only expose organizational shortcomings but also motivate organizations to enable organizational learning and reveal the unrealized potential of digital transformation (Christianson, Farkas, Sutcliffe, & Weick, 2009; Meyer & Simsa, 2018; Phillips et al., 2021). 5.3 Limitations and directions for future research Some studies' limitations are worth mentioning. First, some limitations stem from the methodological approach. In general, case studies have certain limitations such as the tendency of interviewees to show socially accepted behavior or the limited generalizability due to the context-bound nature of the results (Yin, 2009). Consequently, the findings should be interpreted with these limitations in mind. In addition, the number of interviews is relatively limited due to the informants' central and unique role. Nevertheless, we are confident that triangulating interview data from respondents inside and outside the cases with secondary data allowed us to achieve a rich data set to understand the focal phenomenon. Second, in analyzing the effect of the COVID-19 pandemic on the digital transformation of the public sector, we rely on the perspective of representatives of the federal administration about one year after the pandemic started. Although our research approach allows comparing influencing factors across organizations, a more detailed look into the transformation process of single organizations and intra-organizational dynamics would be pertinent. Furthermore, we cannot capture the dynamics of digital government over the years, from the start to the end of the pandemic in 2023, so some further research is needed. Third, whereas understanding the perspective of the supply side of digital government is important to learn about internal challenges, success in transforming toward digital government also depends on the perspectives of the demand side. Future research is recommended to combine this research with the service users' perspective (Gil-Garcia & Flores-Zúñiga, 2020) such as perceptions toward digital government, public critique of COVID-19-related measures, and citizens' trust in the political-administrative system. In addition, future research might focus on adding contextual factors to the analysis (Castelnovo & Sorrentino, 2018). Forth, we aim to examine the effects of the COVID-19 pandemic right after. This means that we cannot conclude whether organizations still adhere to these practices or have already reverted to the original practices. Consequently, exploring organizational practices over time and understanding their long-lasting effects might be an interesting area for future research (Gabryelczyk, 2020). Finally, whereas we emphasize on if and how the pandemic has influenced digital government transformation, it is beyond the scope of this study to evaluate how desirable the associated changes are perceived by organizational members, citizens, and society at large. As Eom and Lee (2022) put it, a pertinent research area would be to analyze “challenges, dilemmas, paradoxes, and ambiguities” associated with the digital government transformation. 6 Conclusion The federal administration played a significant role in coordinating the response to the COVID-19 pandemic. In addition to the introduction of lockdown and social distancing measures, governments worldwide have offered citizens digital solutions to trace contacts and face challenges together. Although online platforms, new apps, and intensive discussion on social media channels provide some indications for governments' digitalization, there is scant empirical research about how the pandemic has affected the digital government transformation and, thus, government transformation beyond the technical system, including the social system. By taking the Austrian federal administration as a research context, this study has shown that the pandemic has not just led to increased use of technological means among individuals but has also influenced various organizational aspects of the federal administration; in particular, individual aspects such as attitudes toward applying new technological means and competencies have improved. The sudden shock has changed people's mindset, meaning that the benefits of using digital means became clear, and perceived risks were reduced. Furthermore, findings indicate that organizations heavily affected by the pandemic without a telework infrastructure and culture or offering several face-to-face services have benefited from a greater degree of digital transformation. Beyond that, we observe transformation processes to a lower but comparable degree in organizations unaffected by the pandemic. The pandemic has therefore influenced a spirit of innovation and accelerated the speed of digital transformation. Consequently, the pandemic can be seen as an incentive from an organizational perspective to take measures that would not have been considered at another time. Author statement Birgit Moser-Plautz made a substantial contribution to this article with respect to conceptualization, data collection, data analysis, and manuscript writing. Lisa Schmidthuber made a substantial contribution to this article with respect to conceptualization and manuscript writing. Funding This work was supported by the Austrian Marshall Plan Foundation [Austrian Marshall Plan Foundation Fellowship 2021]. Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Birgit Moser-Plautz is assistant professor at the Department of Public, Nonprofit & Health Management of the University of Klagenfurt, Austria. She holds a Ph.D. in business administration from the University of Klagenfurt. Her research interests include digital transformation, innovation and change management as well as budgeting and accounting reforms in the public sector. Lisa Schmidthuber is an assistant professor in the Institute for Public Management and Governance, WU Vienna University of Economics and Business, Austria. She obtained her doctoral degree in business administration from Johannes Kepler University Linz in 2018 with a paper-based dissertation on open government and the exploration and exploitation of external knowledge in the public sector. Her research interests include public innovation management (open government, citizensourcing, open data), digital transformation, and accounting innovation (IPSAS & EPSAS). Appendix A Supplementary data Supplementary material Image 1 Appendix A Supplementary material to this article can be found online at https://doi.org/10.1016/j.giq.2023.101815. ==== Refs References Ahn M.J. Chen Y.-C. Digital transformation toward AI-augmented public administration: The perception of government employees and the willingness to use AI in government Government Information Quarterly 39 2 2022 101664 10.1016/j.giq.2021.101664 Biernacki P. Waldorf D. Snowball sampling: Problems and techniques of chain referral sampling Sociological Methods & Research 10 2 1981 141 163 10.1177/004912418101000205 BMKÖS Öffentlicher Dienst—Basiskenndaten https://www.oeffentlicherdienst.gv.at/fakten/oesterreich/basiskenndaten/basiskenndaten.html 2022 Boin A. Hart P. Stern E. Sundelius B. The politics of crisis management: Public leadership under pressure 2016 Cambridge University Press Borins S. Encouraging innovation in the public sector Journal of Intellectual Capital 2 3 2001 310 319 10.1108/14691930110400128 Bostrom R.P. Heinen J.S. MIS problems and failures: A socio-technical perspective. Part I: the causes MIS Quarterly 1 3 1977 17 32 10.2307/248710 Bußjäger P. Schramek C. Austria (Federal Republic of Austria) Griffiths A. Chattopadhyay R. Light J. Stieren C. The forum of federations handbook of Federal Countries 2020 2020 Springer International Publishing 41 52 10.1007/978-3-030-42088-8_4 Castelnovo W. Sorrentino M. The digital government imperative: A context-aware perspective Public Management Review 20 5 2018 709 725 10.1080/14719037.2017.1305693 Christianson M.K. Farkas M.T. Sutcliffe K.M. Weick K.E. Learning through rare events: Significant interruptions at the Baltimore & Ohio Railroad Museum Organization Science 20 5 2009 846 860 10.1287/orsc.1080.0389 Clement J. Esposito G. Crutzen N. Municipal pathways in response to COVID-19: A strategic management perspective on local public administration resilience Administration and Society 00953997221100382 2022 10.1177/00953997221100382 Comfort L.K. Yeo J. Scheinert S.R. Organizational adaptation under stress: Tracing communication processes in four California County health departments during the H1N1 threat, April 28, 2009, to march 11, 2011 The American Review of Public Administration 49 2 2019 159 173 10.1177/0275074018783020 Criado J.I. Guevara-Gómez A. Villodre J. Using collaborative technologies and social media to engage citizens and governments during the COVID-19 crisis. The Case of Spain Digital Government: Research and Practice 1 4 2020 1 7 10.1145/3416089 Czypionka T. Reiss M. Three approaches to handling the COVID-19 crisis in Federal Countries European Journal of Public Health 31 Supplement_3 2021 10.1093/eurpub/ckab164.677 ckab164.677 Danielsen F. Benefits and challenges of digitalization: An expert study on Norwegian public organizations DG.O2021: The 22nd annual international conference on digital government research 2021 317 326 10.1145/3463677.3463703 De Vries H. Bekkers V. Tummers L. Innovation in the public sector: A systematic review and future research agenda Public Administration 94 1 2016 146 166 10.1111/padm.12209 Edelmann N. Mergel I. Co-production of digital public Services in Austrian Public Administrations Administrative Sciences 11 1 2021 22 10.3390/admsci11010022 Edelmann N. Schossboeck J. Albrecht V. Remote work in public sector Organisations: Employees’ experiences in a pandemic context DG.O2021: The 22nd annual international conference on digital government research 2021 408 415 10.1145/3463677.3463725 Eisenhardt K.M. Agency theory: An assessment and review Academy of Management Review 14 1 1989 57 74 10.5465/amr.1989.4279003 Eisenhardt K.M. Graebner M.E. Theory building from cases: Opportunities and challenges Academy of Management Journal 50 1 2007 25 32 10.5465/amj.2007.24160888 Eom S.-J. Lee J. Digital government transformation in turbulent times: Responses, challenges, and future direction Government Information Quarterly 39 2 2022 101690 10.1016/j.giq.2022.101690 European Commission eGovernment benchmark 2021: Entering a new digital government era 2021 Publications Office 10.2759/55088 European Commission DESI - compare countries progress—Digital Scoreboard—Data & Indicators https://digital-strategy.ec.europa.eu/en/policies/desi 2022 Feiock R.C. Lee I.W. Park H.J. Lee K.-H. Collaboration networks among local elected officials: Information, commitment, and risk aversion Urban Affairs Review 46 2 2010 241 262 10.1177/1078087409360509 Fischer C. Heuberger M. Heine M. The impact of digitalization in the public sector: A systematic literature review Der Moderne Staat 14 1 2021 3 4 Gabmayer R. Dohnal F. Luczensky Y. Das Personal des Bundes 2019. Daten und Fakten 2019 Vienna Gabryelczyk R. Has COVID-19 accelerated digital transformation? Initial lessons learned for public administrations Information Systems Management 37 4 2020 303 309 10.1080/10580530.2020.1820633 Gama K. Successful models of hackathons and innovation contests to crowdsource rapid responses to COVID-19 Digital Government: Research and Practice 2 2 2021 1 7 10.1145/3431806 Garcia-Contreras R. Munoz-Chavez P. Valle-Cruz D. Ruvalcaba-Gomez E.A. Becerra-Santiago J.A. Teleworking in times of COVID-19. Some lessons for the public sector from the emergent implementation during the pandemic period: Teleworking in times of COVID-19 DG.O2021: The 22nd annual international conference on digital government research 2021 376 385 10.1145/3463677.3463700 Gil-Garcia J.R. Enacting electronic government success: An integrative study of government-wide websites, organizational capabilities, and institutions 2012 Springer Science & Business Media Gil-Garcia J.R. Dawes S.S. Pardo T.A. Digital government and public management research: Finding the crossroads Public Management Review 20 5 2018 633 646 10.1080/14719037.2017.1327181 Gil-Garcia J.R. Flores-Zúñiga M.Á. Towards a comprehensive understanding of digital government success: Integrating implementation and adoption factors Government Information Quarterly 37 4 2020 101518 10.1016/j.giq.2020.101518 Hammerschmid G. Meyer R.E. New public Management in Austria: Local variation on a global theme? Public Administration 83 3 2005 709 733 10.1111/j.0033-3298.2005.00471.x Ingrams A. Kaufmann W. Jacobs D. Testing the open government recipe: Are vision and voice good governance ingredients? Journal of Behavioral Public Administration 3 1 2020 10.30636/jbpa.31.114 Article 1 Ingrams A. Manoharan A. Schmidthuber L. Holzer M. Stages and determinants of E-government development: A twelve-year longitudinal study of global cities International Public Management Journal 23 6 2020 731 769 10.1080/10967494.2018.1467987 Johns G. The essential impact of context on organizational behavior \| academy of management review Academy of Management Review 31 2 2006 386 408 Kidd S.A. The role of qualitative research in psychological journals Psychological Methods 7 2002 126 138 10.1037/1082-989X.7.1.126 11928887 Kim P.S. South Korea’s fast response to coronavirus disease: Implications on public policy and public management theory Public Management Review 23 12 2021 1736 1747 10.1080/14719037.2020.1766266 Korac S. Saliterer I. Sicilia M. Steccolini I. Contrasting and explaining purposeful and legitimizing uses of performance information: A mayor’s perspective Public Management Review 22 4 2020 553 577 10.1080/14719037.2019.1599059 Lee C. Lee J.M. Liu Y. Catalysing innovation and digital transformation in combating the Covid-19 pandemic: Whole-of government collaborations in ICT, R&D, and business digitization in Singapore Public Money & Management 1–9 2021 10.1080/09540962.2021.1966197 Lee-Geiller S. Lee T. (David). How does digital governance contribute to effective crisis management? A case study of Korea’s response to COVID-19 Public Performance & Management Review 0 0 2022 1 34 10.1080/15309576.2022.2054434 Leixnering S. Schikowitz A. Meyer R.E. Austria: nothing is different, but everything’s changed Hammerschmid G. Van de Walle S. Andrews R. Bezes P. Public administration reforms in Europe 2016 Edward Elgar Publishing 41 51 10.4337/9781783475407.00010 Lin J. Carter L. Liu D. Privacy concerns and digital government: Exploring citizen willingness to adopt the COVIDSafe app European Journal of Information Systems 30 4 2021 389 402 10.1080/0960085X.2021.1920857 Mayring P. Qualitative content analysis: Theoretical foundation, basic procedures and software solution 2014 Mergel I. Opening government: Designing open innovation processes to collaborate with external problem solvers Social Science Computer Review 33 5 2015 599 612 10.1177/0894439314560851 Mergel I. Digital service teams in government Government Information Quarterly 36 4 2019 101389 10.1016/j.giq.2019.07.001 Mergel I. Edelmann N. Haug N. Defining digital transformation: Results from expert interviews Government Information Quarterly 36 4 2019 101385 10.1016/j.giq.2019.06.002 Meyer M. Simsa R. Organizing the unexpected: How civil society organizations dealt with the refugee crisis Voluntas: International Journal of Voluntary and Nonprofit Organizations 29 6 2018 1159 1175 10.1007/s11266-018-00050-y Moon M.J. Shifting from old open government to new open government: Four critical dimensions and case illustrations Public Performance & Management Review 43 3 2020 535 559 10.1080/15309576.2019.1691024 OECD Government at a glance 2021 2021 OECD 10.1787/1c258f55-en Omar A. Weerakkody V. Daowd A. Studying transformational government: A review of the existing methodological approaches and future outlook Government Information Quarterly 37 2 2020 101458 10.1016/j.giq.2020.101458 Oschinsky F.M. Stelter A. Niehaves B. Cognitive biases in the digital age – How resolving the status quo bias enables public-sector employees to overcome restraint Government Information Quarterly 38 4 2021 101611 10.1016/j.giq.2021.101611 Park C.H. Richards R.C. Reedy J. Assessing emergency information sharing between the government and the public during the COVID-19 pandemic: An open government perspective Public Performance & Management Review 0 0 2022 1 32 10.1080/15309576.2022.2048400 Phillips W. Roehrich J.K. Kapletia D. Responding to information asymmetry in crisis situations: Innovation in the time of the COVID-19 pandemic Public Management Review 1–24 2021 10.1080/14719037.2021.1960737 Polzer T. Goncharenko G. The UK COVID-19 app: The failed co-production of a digital public service Financial Accountability & Management 18 2021 10.1111/faam.12307 Polzer T. Seiwald J. Outcome orientation in Austria: How far can late adopters move? Hoque Z. Public sector reform and performance Management in Developed Economies 2021 Routledge 10.4324/9781003004080 Reina R. Ventura M. Cristofaro C.L. Vesperi W. Digitalize work in pandemic time: Practices for remote working and job redesign in public organization Mondal S.R. Di Virgilio F. Das S. HR analytics and digital HR practices: Digitalization post COVID-19 2022 Springer 73 99 10.1007/978-981-16-7099-2_4 Sandoval-Almazan R. Valle-Cruz D. Social media use in government health agencies: The COVID-19 impact Information Polity 26 4 2021 459 475 10.3233/IP-210326 Scholta H. Mertens W. Kowalkiewicz M. Becker J. From one-stop shop to no-stop shop: An e-government stage model Government Information Quarterly 36 1 2019 11 26 10.1016/j.giq.2018.11.010 Shields B. Inside the first movers group of countries that turned virus around 2020 The Sydney Morning Herald https://www.smh.com.au/world/europe/inside-the-first-movers-group-of-countries-that-turned-virus-around-20200619-p554ft.html Tangi L. Janssen M. Benedetti M. Noci G. Barriers and drivers of digital transformation in public organizations: Results from a survey in the Netherlands Viale Pereira G. Janssen M. Lee H. Lindgren I. Rodríguez Bolívar M.P. Scholl H.J. Zuiderwijk A. Electronic government 2020 Springer International Publishing 42 56 10.1007/978-3-030-57599-1_4 Tangi L. Janssen M. Benedetti M. Noci G. Digital government transformation: A structural equation modelling analysis of driving and impeding factors International Journal of Information Management 60 2021 102356 10.1016/j.ijinfomgt.2021.102356 United Nations UN E-Government Survey 2020 2020 https://publicadministration.un.org/egovkb/en-us/Reports/UN-E-Government-Survey-2020 Vermicelli S. Cricelli L. Grimaldi M. How can crowdsourcing help tackle the COVID-19 pandemic? An explorative overview of innovative collaborative practices R&D Management 51 2 2021 183 194 10.1111/radm.12443 Vial G. Understanding digital transformation: A review and a research agenda The Journal of Strategic Information Systems 28 2 2019 118 144 10.1016/j.jsis.2019.01.003 Wanckel C. An ounce of prevention is worth a pound of cure – Building capacities for the use of big data algorithm systems (BDAS) in early crisis detection Government Information Quarterly 39 4 2022 101705 10.1016/j.giq.2022.101705 Wilson C. Mergel I. Overcoming barriers to digital government mapping the strategies of digital champions Government Information Quarterly 101681 2022 10.1016/j.giq.2022.101681 Yin R.K. Case study research: Design and methods 2009 SAGE
PMC010xxxxxx/PMC10019791.txt	==== Front Stat Biosci Stat Biosci Statistics in Biosciences 1867-1764 1867-1772 Springer US New York 9366 10.1007/s12561-023-09366-w Article On the Methodological Aspects of the Clinical Trials for COVID-19 Conducted in the First Year of the Pandemic: A Descriptive Analysis Georgiadi Eleni [email protected] 1 http://orcid.org/0000-0003-0546-3162 Sachlas Athanasios [email protected] 2 1 grid.5216.0 0000 0001 2155 0800 Department of Medicine, National and Kapodistrian University of Athens, Mikras Asias 75, Athens, 115 27 Greece 2 grid.410558.d 0000 0001 0035 6670 Department of Computer Science and Biomedical Informatics, University of Thessaly, Papasiopoulou 2-4, Lamia, 351 31 Greece 16 3 2023 2023 15 2 384396 22 8 2022 3 1 2023 28 2 2023 © The Author(s) under exclusive licence to International Chinese Statistical Association 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. In 2020, the whole planet was plagued by the extremely deadly COVID-19 pandemic. More than 83 million people had been infected with COVID-19 while more than 1.9 million people around the planet had died from this virus in the first year of the pandemic. From the first moment, the medical community started working to deal with this pandemic. For this reason, many clinical trials have been and continue to be conducted to find a safe and efficient cure for the virus. In this paper, we review the 96 clinical trials, registered in the ClinicalTrials.gov database, that had been completed by the end of the first year of the pandemic. Although the clinical trials contained significant heterogeneity in the main methodological features (enrollment, duration, allocation, intervention model, and masking) they seemed to be conducted based on an appropriate methodological basis. Keywords COVID-19 Clinical trials Descriptive analysis Pandemic Risk of bias SARS-CoV-2 Statistical design issue-copyright-statement© International Chinese Statistical Association 2023 ==== Body pmcIntroduction The COVID pandemic, or COVID-19 virus, is due to a virus belonging to the family of coronaviruses which was first discovered in 1964 in London by June Almeida [1]. What most viruses in this category can cause is a respiratory infection and in some cases even pneumonia. It was 2002 in China when coronavirus caused severe acute respiratory syndrome (known as SARS) until in December 2019 a new type of coronavirus appeared, the one of Wuhan, known as SARS-CoV-2, which is responsible for the pandemic [2, 3]. According to the World Health Organization (WHO), a significantly large number of people were infected (about 83 million) and died from the virus (about 1.9 million) in 2020. For the above reasons, scientists studied how the virus attacks human cells and came to the conclusion that the interaction of glycoprotein ACE2 of the virus in combination with heparin sulfate located in the cell membrane, allows the virus to enter the cell and then begins to multiply [3, 4]. COVID-19 may attack all groups of people in different ways. Most infected people experience mild to moderate symptoms and recover without having to be hospitalized. The most common symptoms include fever, dry cough, and tiredness while more rare symptoms such as pain, diarrhea, conjunctivitis, headache, sore throat, loss of taste or smell, a skin rash, or discoloration on the fingers or toes will occur [5–8]. Based on retrospective studies, which evaluated how various characteristics such as age, gender of men, increased body mass index (BMI), comorbidities including diabetes, chronic obstructive pulmonary disease (COPD), cerebrovascular disease, and hypertension may play a role in virus infection, it was found that there is some positive association with an increased risk of coronavirus infection for people who carry the above characteristics [9]. In addition to these characteristics, environmental as well as genetic factors may also increase sensitivity to COVID-19 [10]. In recent years, it has been widely recognized that properly designed and carefully implemented clinical trials, which follow the principles of scientific experimentation, provide the only reliable basis for evaluating the efficiency and safety of new treatments. Clinical trials are essentially clinical trials involving mostly humans. Conducting an effective and useful clinical study is mainly related to its proper design since in clinical trials there are many aspects that must be taken into account both organizational and ethical. Several authors have dealt with the methodological or non-methodological characteristics of clinical trials by retrieving data from the ClinicalTrials.gov database. Hirsch et al. [11] studied the characteristics of oncology clinical trials while Chen et al. [12] reviewed the characteristics of traditional Chinese medicine clinical trials. Hill et al. [13] reviewed the characteristics of 284 pediatric cardiovascular clinical trials. Dechartres et al. [14] described the characteristics of completed phase III or IV clinical trials of rare diseases and assessed whether their results were publicly available. Cheng et al. [15] studied the key design characteristics of 53 geographic atrophy clinical trials while Dammo et al. [16] conducted a cross-sectional study to examine the characteristics of 151 studies of pharmacist services. Califf et al. [17] reviewed the fundamental characteristics of 96,346 clinical trials registered in ClinicalTrials.gov in the period 2007–2010. Recently, Pundi et al. [18] evaluated the characteristics and expected strength of evidence of COVID-19 studies. The aim of this paper is to assess whether the clinical trials for COVID-19 conducted in the first year of the pandemic followed the basic methodological requirements, i.e., enrollment, duration, allocation, intervention model, and masking. The paper is organized as follows. In the second section, we briefly discuss the basic statistical methodological characteristics of clinical trials. In the third section, we briefly describe the way we retrieved the reviewed clinical trials. In Section 4, we present the basic methodological aspects of these clinical trials, while in Section 5 we critically discuss the results of the study. Concluding remarks are presented in the last section. Statistical Characteristics of Clinical Trials According to Pocock [19], a clinical trial is a randomized trial that aims to evaluate the effectiveness and safety of a treatment. In the case of two or more treatments, the purpose of the clinical trial is to compare the treatments for efficacy and safety. Clinical trials are classified into four phases [19]. Phase I clinical trials aim mainly at the safety and not the effectiveness of the drug under study. Phase II clinical trials are small-scale (100–200 people) studies on the efficacy and safety of the treatment under test. Once a Phase II clinical trial has shown that a treatment is effective, it should be compared to standard treatment (or treatments) for the same disease or condition. This comparison is made through a large-scale Phase III clinical trial, in which a large number of patients (1000–3000 patients) participate. Finally, once the treatments have been approved and released, there are issues that need to be monitored, mainly in terms of side effects, or additional long-term morbidity or mortality studies. This is the purpose of Phase IV clinical trials. To achieve an unbiased assessment of the new treatment, it is necessary to adhere to the fundamental statistical principle of randomization. According to this, the administration of both the new and the standard treatment to the patients should be done in a random way. Nowadays it is generally accepted that randomized controlled clinical trial is the most reliable way of conducting clinical medical research. The use of a placebo (i.e., an inert treatment), as well as the comparison of two treatments, allows the masking or blinding of a medical study. This term refers to which of the parties involved in a clinical trial (participants, care providers, investigators, and outcomes assessors) are unaware of the treatment assigned to participants. The main types of masking are open-label, single-blind masking, and double-blind masking. Another crucial feature of clinical trials is the calculation of the sample size, i.e., the calculation of the number of people who will take part in the trial [20]. In order for the sample size to be valid, it should be calculated on the basis of appropriate statistical tests. There are two ways to calculate the sample size: precision analysis or power analysis. The first is performed by controlling the type I error (or the confidence level) while the latter by controlling the type II error (or the power of the test). The simplest design for a clinical trial is the single group assignment, in which all participants receive the same intervention or treatment. However, in most of the cases, there are two or more groups of participants receiving different interventions [19]. The simplest form of this design is the parallel assignment, in which two or more groups of participants receive a different treatment [19]. The sequential assignment requires interim analyses, the outcome of which determines whether additional patients will enter the study or the study will be terminated [19]. In the factorial assignment groups of participants receive one of several combinations of treatments [19]. For example, a two-by-two factorial assignment involves four groups of participants, where each group receives one of the four possible pairs of treatments The most complex study intervention model is cross-over assignment, in which groups of participants receive two or more interventions in a specific order [19]. For example, a two-by-two cross-over assignment involves two groups of participants of which one group initially receives treatment A and then treatment B. The second group receives treatment B during the initial phase and then treatment A. All participants receive treatment A and treatment B at some time during the clinical trial, but in a different order, based on the group to which they have been assigned. Method To retrieve the relevant completed clinical trials conducted during 2020 (i.e., the first year of the pandemic), we searched the ClinicalTrials.gov database on March 21, 2022, using the following keywords: COVID-19, Coronavirus, and Coronavirus Infection. Here we should note that ClinicalTrials.gov automatically searched for COVID and SARS-CoV-2 when we used the COVID-19 keyword. ClinicalTrials.gov is a database, provided by the U.S. National Library of Medicine, of both privately and publicly funded clinical studies conducted around the world. Our search was restricted to the Phase II and III clinical trials because only in these two phases formal statistical designs are applied. After removing duplicates, a total of 96 clinical trials were retrieved and analyzed. Continuous variables were presented as mean (standard deviation) while categorical variables were presented as absolute (relative) frequencies. The non-parametric Kruskal–Wallis test was used to compare the quantitative characteristics of the clinical trials among their phases and intervention model. The Pearson’s chi-square test was performed to assess the association between qualitative variables. The IBM SPSS Statistics 28 and the R language were used for the statistical analysis. The quality of the clinical trials methodology was assessed through the Cochrane bias risk assessment tool. A total of 6 items were included (i.e., selection bias, performance bias, detection bias, attrition bias, reporting bias, and other types of bias) and each item was identified as either high risk, low risk, or unclear. The assessment was done, by both authors, according to whether the clinical trials provided information about these types of bias. Results Unstratified Analysis Ninety-six clinical trials for COVID-19 had been completed by the time this survey was conducted. 40 out of 96 clinical trials (41.7%) were large-scale Phase III clinical trials, 40 were small-scale Phase II clinical trials, while 16 (16.7%) were a combination of Phase II/Phase III clinical trials. 84 of the clinical trials were randomized, 6 were non-randomized, and for 6 of them, the allocation was not recorded. 34 out of the 40 Phase II clinical trials, 15 out of the 16 Phase II/Phase III clinical trials, and 33 out of the 40 Phase III clinical trials have not yet reported results uploaded on the ClinicalTrials.gov database, and thus we cannot assess them. In all the Phase II and Phase II/Phase III clinical trials and in 39 of the 40 Phase III clinical trials participants of both sexes participated; in the one remaining Phase III clinical trial only men participated. The average number of participants was 372.47 (± 740.60) people. The number of participants ranged from 5 to 4891 people. The box-plot of the number of participants after removing 3 clinical trials with an enrollment of more than 2000 participants, is given in Fig. 1a. The median number of participants was about 120 people. The average duration of the clinical trials was 146.64 (± 160.04) days, i.e., 4.33 months. The duration ranged from 15 to 1401 days. The box-plot of the duration of the completed clinical trials, after removing 3 clinical trials with a duration of more than 550 days, is given in Fig. 1b. The median duration was about 3 months. The relation between the number of participants and the duration of the clinical trials is given in Fig. 2. For Phase II and for Phase II/Phase III clinical trials a significant relation was observed (Spearman’s rho=0.538, p<0.001 and Spearman’s rho = 0.689, p=0.040, respectively).Fig. 1 The box-plots for the number of participants after removing 3 clinical trials with enrollment more than 2000 participants (a) and the clinical trial duration after removing 3 clinical trials with duration more than 550 days (b) Fig. 2 The relation between the number of participants and the duration of the clinical trials The majority (82 out of 96) of the clinical trials used a parallel assignment design. Seven clinical trials used a single-group assignment, three used a crossover design, two used a factorial assignment, and two used a sequential design. Almost half of the clinical trials (49 out of 96) used no masking, i.e., all involved were aware of the treatment. Five clinical trials used single masking; in three clinical trials, the participants were unaware of the treatment, in two clinical trials the outcomes assessor was unaware, while in one clinical trial the investigator was unaware of the treatment. 20 clinical trials used double masking; in 13 clinical trials, the participants and the investigators were unaware, in four clinical trials the participants and the care providers were unaware, while in three clinical trials the participants and the outcomes assessor were unaware of the treatment. Six clinical trials used triple masking; in two of them the participants, the care providers, and the outcomes assessors were unaware, in two the care providers, the investigators, and the outcomes assessor were unaware, in one clinical trial the participants, the care providers, and the investigators were unaware, and in one clinical trial the participants, the investigators, and the outcomes assessors were unaware of the treatment. Finally, in 15 clinical trials, quadruple masking was used, i.e., all involved (participants, care providers, investigators, and outcomes assessors) were unaware of the treatment. The clinical trials assessed a variety of multiple outcomes/endpoints. The most prevalent was mortality, followed by the presence of side effects and the duration of hospitalization. Analysis Per Phase The methodological characteristics of the clinical trials per phase are presented in Table 1. As we can observe, the average enrollment of Phase II clinical trials was considerably smaller than the average duration of Phase III clinical trials (p< 0.001). The stratified analysis also showed that the 25% of Phase II clinical trials had fewer than 30 participants while the 25% of Phase III clinical trials had fewer than 101 participants. Half of Phase II clinical trials had 60 participants while half of Phase III clinical trials had 294 participants. The 75% of Phase II clinical trials had less than 140 participants while the 75% of Phase III clinical trials had less than 525 participants. No significant differences in the duration of the clinical trials were revealed among the phases (p = 0.949). Moreover, 25% of Phase II clinical trials were completed in about 2 and a half months while the 25% of Phase III clinical trials were completed in about 3 months. Half of Phase II clinical trials were completed in about three and a half months while half of Phase III clinical trials were completed in less than 4 months. The 75% of Phase II clinical trials were completed in about 6 and a half months while the 75% of Phase III clinical trials were completed in about 5 and a half months. The 80% of Phase II, the 93.7% of Phase II–III, and the 92.5% of Phase III clinical trials used a randomization allocation. There was no significant association between the phase and the allocation of the clinical trials (p= 0.065). 33 out of the 40 Phase II clinical trials used a parallel assignment design. The other 7 Phase II clinical trials used a single-group assignment design. The majority of Phase III clinical trials (37 out of 40) also used a parallel assignment design. Two Phase III clinical trials used a crossover design and one used a factorial design. Regarding the Phase II–III clinical trials, 12 of them used a parallel design, two used a sequential design, one used a crossover design, and one used a factorial design. A significant association between the phase and the intervention model emerged (p< 0.001). Regarding masking, the majority of all phases used no masking. A significant association between the phase and the masking emerged (p= 0.027).Table 1 The methodological characteristics of the clinical trials per phase Phase I Phase II–Phase III Phase III p-value (n=40) (n=16) (n=40) Enrollment 106.67 (121.423) 430.81 (593.184) 614.93 (1025.590) < 0.001 Duration (days) 134.70 (93.071) 198.38 (324.377) 137.88 (109.242) 0.949 Allocation Non-Randomized 2 (5.0) 1 (6.3) 3 (7.5) Randomized 32 (80.0) 15 (93.7) 37 (92.5) 0.063 NA 6 (15.0) 0 (0.0) 0 (0.0) Intervention model Single-group Assignment 7 (17.5) 0 (0.0) 0 (0.0) Parallel assignment 33 (82.5) 12 (75.0) 37 (92.5) Sequential assignment 0 (0.0) 2 (12.5) 0 (0.0) < 0.001 Crossover assignment 0 (0.0) 1 (6.3) 2 (5.0) Factorial assignment 0 (0.0) 1 (6.3) 1 (2.5) Masking None 26 (65.0) 5 (31.3) 18 (45.0) Single 0 (0.0) 4 (25.0) 3 (5.0) Double 6 (15.0) 2 (12.5) 12 (30.0) 0.027 Triple 2 (5.0) 1 (6.3) 3 (7.5) Quadruple 6 (15.0) 4 (25.0) 5 (12.5) Enrollment and Duration are presented as mean (standard deviation) NA not applicable Analysis Per Intervention Model In Table 2, the methodological characteristics of the 96 clinical trials per intervention model are presented. Crossover clinical trials and single-group clinical trials had the smallest average sample size (83 and 92, respectively) while the clinical trials with factorial assignment had the larger average sample size. The clinical trials with single-group assignment, sequential assignment, and crossover assignment had the smallest duration (about 3 to 3 and a half months on average). The clinical trials with a factorial design had the largest duration (about 14 months on average). All seven clinical trials with single-group assignment were of Phase II, while the clinical trials with parallel groups were approximately evenly distributed in the two phases. The more complex designs were used for Phase III or a combination of Phase II and Phase III clinical trials. The majority of all clinical trials, except those with a single-group assignment, used randomization to administer the treatments to the patients. Two out of the three crossover clinical trials used no blinding. This was also the case in about half of the clinical trials with the parallel and sequential assignments (Table 2).Table 2 The methodological characteristics of the clinical trials per intervention model Single-Group Parallel Sequential Crossover Factorial p-value Assignment Assignment Assignment Assignment Assignment (n = 7) (n = 82) (n = 2) (n = 3) (n = 2) Enrollment 91.14 (178.65) 395.48 (776.97) 291.00 (69.30) 82.67 (84.32) 930.00 (1230.37) 0.036 Duration (days) 100.29 (61.88) 146.05 (159) 107.50 (70.00) 104.67 (77.02) 435.00 (393.15) 0.367 Phases Phase II 7 (100.0) 33 (40.2) 0 (0.0) 0 (0.0) 0 (0.0) Phase II-Phase III 0 (0.0) 12 (14.6) 2 (100.0) 1 (33.7) 1 (50.0) < 0.001 Phase III 0 (0.0) 37 (45.1) 0 (0.0) 2 (66.7) 1 (50.0) Allocation Non-Randomized 1 (14.3) 4 (4.9) 0 (0.0) 1 (33.3) 0 (0.0) Randomized 0 (0.0) 78 (95.1) 2 (100.0) 2 (66.7) 2 (100.0) < 0.001 NA 6 (85.7) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0) Masking None 7 (100.0) 39 (47.6) 1 (50.0) 2 (66.7) 0 (0.0) Single 0 (0.0) 5 (6.1) 0 (0.0) 0 (0.0) 1 (50.0) Double 0 (0.0) 19 (23.2) 0 (0.0) 1 (33.7) 0 (0.0) 0.158 Triple 0 (0.0) 5 (6.1) 0 (0.0) 0 (0.0) 1 (50.0) Quadruple 0 (0.0) 14 (17.1) 1 (50.0) 0 (0.0) 0 (0.0) Enrollment and Duration are presented as mean (standard deviation) NA not applicable Risk of Bias Figure 3 presents the Cochrane bias risk assessment results. As it is presented the quality of the clinical trials methodology is somehow uncertain. The majority of the clinical trials reported randomization (selection bias), while only six trials had a high risk of bias in the randomization; six clinical trials did not mention such information. The risk of performance bias was approximately equal; almost half of the clinical trials had a low risk of performance bias. Regarding detection bias, about 74% had a high risk of such a bias. The risk of attrition bias, reporting bias, or another bias was unclear, as none of the clinical trials provided such information.Fig. 3 Risk of bias assessment Discussion During the first year of the pandemic, 96 clinical trials on COVID-19 had been completed. Although the ClinicalTrials.gov database has a number of limitations, it is the most comprehensive resource for information on clinical trials. The retrieved trials showed several differences in their methodological characteristics even within the various phases. An important feature of clinical trials that affects the validity of their results is the sample size. Our study showed that the 25% of Phase II clinical trials had less than 30 participants while the 25% of Phase III clinical trials had less than 101 participants. For both phases of the clinical trials, these sizes are small enough. Phase III clinical trials had approximately six times the sample size of Phase II clinical trials, which is reasonable. One would expect the clinical trials using a more complex design to be larger in size as well. However, this was only the case for factorial design. Clinical trials with a crossover design had enrolled on average 83 participants; the least in comparison to all other intervention models. Freiman et al. [21] highlighted the significant role that the sample size plays in the design and interpretation of clinical trials. The majority of the clinical trials, regardless of phase and design, were randomized, which is important for the reliability of the trials. As Kang et al. [22] mentioned, the implementation of randomization increases both the power and validity of the results and improves the quality of the provided care. The dominant design, regardless of phase, was the parallel assignment. This is reasonable to some extent since the researchers are trying to quickly develop an effective therapy for a disease that so far seems to be very resistant. However, more complex designs, such as factorial or cross-over designs, could improve the reliability of clinical trials’ results. It is encouraging that some clinical trials used such designs. Although there is no perfect study design for every test situation, Nair [23] provided a general algorithm for the choice of the appropriate study design for several test situations. A negative point of the completed clinical trials on COVID-19 is that almost all Phase II clinical trials and almost half of the Phase III trials used no blinding. As Schulz and Grimes [24] mentioned, blinding usually reduces information bias, on the one hand, and improves compliance and retention of the participants, on the other hand. Unfortunately, a significant number of studies do not contain proper reporting on this information. The fact that the participants knew the treatment they were given may have affected the results. It would be beneficial for the reliability of the results of the clinical trials at least for participants and care providers to be unaware of the treatment. Many times, researchers are paying more attention to quick results than the correct design of the clinical trials. However, the duration of a clinical trial is affected by several factors such as the design, the endpoints, the sample size, and the sampling methods [25]. Several authors have dealt with the minimization of the duration of clinical trials by proposing appropriate stopping rules [26–28]. For the present study, it was not possible to study the factors that affected the duration of the retrieved clinical trials as this information is not contained in the ClinicalTrials.gov database. Due to the nature of the study, some limitations exist. The results derived are representative only of the clinical trials registered in the ClinicalTrials.gov database; some trials may not be registered in the database. Moreover, given that the characteristics are submitted by sponsors or investigators, may be subject to error. Due to missing values (not entered into the database), it was not possible to perform more complex analyses (e.g., multivariate analysis). Additional characteristics of the clinical trials that could have been recorded are whether a sample size calculation was made and if so in what way, the sampling methods, which statistical techniques were used to analyze the data, etc. Conclusion A total of 96 clinical trials on COVID-19 have been completed until the time of the database search. Although the registered trials contain significant heterogeneity in their methodological features, the majority of them follow a proper methodological design. This means that the scientific community is ready to quickly and effectively deal with emergency situations such as the appearance of the coronavirus at the end of 2019. However, we should be very careful when reading the results of clinical trials and always interpret them taking into account their methodological characteristics. Acknowledgements We would like to thank very much the two Reviewers for their valuable comments and suggestions that helped us to improve the quality of the original manuscript. Declarations Conflict of interest The authors have no competing interests to declare that are relevant to the content of this article. ==== Refs References 1. The woman who discovered the first coronavirus, https://www.bbc.com/news/uk-scotland-52278716. Accessed: 09 Dec 2020 2. Naming the coronavirus disease (covid-19) and the virus that causes it, https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance/naming-the-coronavirus-disease-(covid-2019)-and-the-virus-that-causes-it. Accessed: 09 Dec 2020 3. Murray P, Rosenthal K, Pfaller M (2020) Medical microbiology E-book. Elsevier Health Sciences 4. Sars-cov-2 may use key carbohydrate to infect cells, https://www.nih.gov/news-events/nih-research-matters/sars-cov-2-may-use-key-carbohydrate-infect-cells. Accessed: 10 Dec 2020 5. Chen G Wu D Guo W Cao Y Huang D Wang H Wang T Zhang X Chen H Yu H Clinical and immunologic features in severe and moderate forms of coronavirus disease J Clin Invest 2019 130 2620 2629 10.1172/JCI137244 6. Chen N Zhou M Dong X Qu J Gong F Han Y Qiu Y Wang J Liu Y Wei Y Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study The Lancet 2020 395 507 513 10.1016/S0140-6736(20)30211-7 7. Qiu H Wu J Hong L Luo Y Song Q Chen D Clinical and epidemiological features of 36 children with coronavirus disease 2019 (COVID-19) in Zhejiang, China: an observational cohort study Lancet Infect Dis 2020 20 689 96 10.1016/S1473-3099(20)30198-5 32220650 8. Tian S Hu N Lou J Chen K Kang X Xiang Z Chen H Wang D Liu N Liu D Characteristics of COVID-19 infection in Beijing J Infect 2020 80 401 406 10.1016/j.jinf.2020.02.018 32112886 9. Wang B Li R Lu Z Huang Y Does comorbidity increase the risk of patients with COVID-19: evidence from meta-analysis Aging (Albany NY) 2020 12 6049 10.18632/aging.103000 32267833 10. Knittel C, Ozaltun B (2020) What does and does not correlate with COVID-19 death rates. MedRxiv 11. Hirsch B Califf R Cheng S Tasneem A Horton J Chiswell K Schulman K Dilts D Abernethy A Characteristics of oncology clinical trials: insights from a systematic analysis of ClinicalTrials. gov JAMA Intern Med 2013 173 972 979 10.1001/jamainternmed.2013.627 23699837 12. Chen J Huang J Li J Lv Y He Y Zheng Q The characteristics of tcm clinical trials: a systematic review of clinicaltrials.gov Evid-Based Complement Altern Med 2017 2017 9461415 10.1155/2017/9461415 13. Hill K Chiswell K Califf R Pearson G Li J Characteristics of pediatric cardiovascular clinical trials registered on ClinicalTrials. gov Am Heart J 2014 167 921 929 10.1016/j.ahj.2014.02.002 24890544 14. Dechartres A Riveros C Harroch M Faber T Ravaud P Characteristics and public availability of results of clinical trials on rare diseases registered at clinicaltrials. gov JAMA Intern Med 2016 176 556 558 10.1001/jamainternmed.2016.0137 26954340 15. Cheng Q Gao J Kim B Ying G Design characteristics of geographic atrophy treatment trials: systematic review of registered trials in ClinicalTrials. gov Ophthalmol Retina 2018 2 518 525 10.1016/j.oret.2017.08.018 31047604 16. Dammo N Harpe S Characteristics of studies of pharmacist services registered in ClinicalTrials. gov J Am Pharm Assoc 2020 60 609 617 10.1016/j.japh.2019.12.001 17. Califf R Zarin D Kramer J Sherman R Aberle L Tasneem A Characteristics of clinical trials registered in ClinicalTrials.gov, 2007-2010 JAMA 2012 307 1838 1847 10.1001/jama.2012.3424 22550198 18. Pundi K Perino A Harrington R Krumholz H Turakhia M Characteristics and strength of evidence of COVID-19 studies registered on ClinicalTrials. gov JAMA Intern Med 2020 180 1398 1400 10.1001/jamainternmed.2020.2904 32730617 19. Pocock S Clinical trials: a practical approach 2013 Hoboken Wiley 20. Jones S Carley S Harrison M An introduction to power and sample size estimation Emerg Med J: EMJ. 2003 20 453 10.1136/emj.20.5.453 12954688 21. Freiman J Chalmers T Smith H Kuebler R The importance of beta, the type II error and sample size in the design and interpretation of the randomized control trial New Engl J Med 1978 299 690 694 10.1056/NEJM197809282991304 355881 22. Kang M Ragan B Park J Issues in outcomes research: an overview of randomization techniques for clinical trials J Athl Train 2008 43 215 221 10.4085/1062-6050-43.2.215 18345348 23. Nair B Clinical trial designs Indian Dermatol Online J 2019 10 193 10.4103/idoj.IDOJ_475_18 30984604 24. Schulz K Grimes D Blinding in randomised trials: hiding who got what The Lancet 2002 359 696 700 10.1016/S0140-6736(02)07816-9 25. Chander N Sample size estimation J Indian Prosthodont Soc 2017 17 217 218 10.4103/jips.jips_169_17 28936033 26. Bersimis S Sachlas A Papaioannou T Flexible designs for phase II comparative clinical trials involving two response variables Stat Med 2015 34 197 214 10.1002/sim.6317 25274584 27. Stallard N Whitehead J Todd S Whitehead A Stopping rules for phase II studies Br Clin Pharmacol 2001 51 523 529 10.1046/j.0306-5251.2001.01381.x 28. Todd S Whitehead A Stallard N Whitehead J Interim analyses and sequential designs in phase III studies Br J Clin Pharmacol 2001 51 394 399 10.1046/j.1365-2125.2001.01382.x 11421995
PMC010xxxxxx/PMC10020132.txt	==== Front J Microbiol Immunol Infect J Microbiol Immunol Infect Journal of Microbiology, Immunology, and Infection 1684-1182 1995-9133 Taiwan Society of Microbiology. Published by Elsevier Taiwan LLC. S1684-1182(23)00071-3 10.1016/j.jmii.2023.03.003 Original Article Long term SARS-CoV-2-specific cellular immunity after COVID-19 in liver transplant recipients Citores Maria J. a∗ Caballero-Marcos Aranzazu bc Cuervas-Mons Valentín de Alonso-Fernández Roberto f Graus-Morales Javier g Arias-Milla Ana d Valerio Maricela f Muñoz Patricia f Salcedo Magdalena bc a Laboratorio de Medicina Interna, Hospital Universitario Puerta de Hierro Majadahonda, IDIPHISA, Madrid, Spain b Hepatology and Liver Transplantation Unit, Hospital General Universitario Gregorio Marañón, Facultad de Medicina Universidad Complutense, Madrid, Spain c Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain d Unidad de Trasplante Hepático, Servicio de Medicina Interna, Hospital Universitario Puerta de Hierro Majadahonda, IDIPHISA, Madrid, Spain e Departamento de Medicina, Facultad de Medicina, Universidad Autónoma de Madrid (UAM), Madrid, Spain f Department of Clinical Microbiology and Infectious Diseases, Hospital General Universitario Gregorio Marañón, Madrid, Spain g Department of Digestive Diseases, Hospital Ramón y Cajal, IRYCIS, Madrid, Spain ∗ Corresponding author. Hospital Universitario Puerta de Hierro Majadahonda, Edificio de Laboratorios, Planta 3, Laboratorio de Medicina Interna, Joaquin Rodrigo 2, Majadahonda, 28222, Madrid. Spain. 17 3 2023 6 2023 17 3 2023 56 3 526536 15 9 2022 9 2 2023 7 3 2023 © 2023 Taiwan Society of Microbiology. Published by Elsevier Taiwan LLC. 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Purpose Long-term immunity after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in immunosuppressed patients is not well characterized. We aimed to explore the long-term natural immunity against SARS-CoV-2 in liver transplant (LT) recipients compared to the non-transplanted population (control group). Methods Fifteen LT recipients and 15 controls matched according to variables associated with disease severity were included at 12 months following the coronavirus disease 2019 (COVID-19) onset. Peripheral blood mononuclear cells were stimulated with peptide pools covering spike (S), nucleocapside (N), and membrane (M) proteins. Reactive CD4+ and CD8+ T cells were identified using flow cytometry, and cytokine production was evaluated in the culture supernatants using cytometric bead array. Serum anti-N and anti-S IgG antibodies were detected with chemiluminescence. Results The percentage of patients with a positive response in both CD4+ and CD8+ T cells against each viral protein and IL2, IL10, TNF-α, and IFN-γ levels was similar between LT recipients and controls. IFN-γ levels were positively correlated with the percentage of reactive CD4+ (p = 0.022) and CD8+ (p = 0.043) T cells to a mixture of M + N + S peptide pools. The prevalence and levels of anti-N and anti-S IgG antibodies were slightly lower in the LT recipients, but the difference was not statistically significant. Conclusion LT recipients exhibited a similar T cell response compared to non-transplanted individuals one year after COVID-19 diagnosis. Keywords Flow cytometry Humoral immunity Liver transplantation Reactive T cells SARS-CoV-2 Abbreviations SARS-CoV-2 Severe acute respiratory syndrome coronavirus 2 COVID-19 Coronavirus disease 2019 LT liver transplant S Spike N Nucleocapside M Membrane PBMC Peripheral blood mononuclear cells SD standar deviation TNF tumor necrosis factor IFN interferon IQR interquartile range DP double positive SOT solid organ transplantation ==== Body pmcIntroduction Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly become a public health issue profoundly affecting healthcare systems worldwide, including liver transplantation (LT) programs. Knowledge of the natural history of the disease is progressively increasing; however, the durability of adaptive immunity to SARS-CoV-2 after natural infection in immunocompromised patients remains unclear. The induction of effective and durable immune memory, in both humoral and cellular arms, is essential to prevent severe disease and protect against reinfection. A broad immune response to SARS-CoV-2 has been well documented, with multiple epitopes of membrane (M) glycoprotein, nucleocapsid (N) phosphoprotein, and spike (S) protein being the most prominent targets of specific T and B cells.1 , 2 Previous studies have shown long-term persistence of S-specific IgG+ memory B cells and virus-specific CD4+ and CD8+ T cells3 in immunocompetent patients. In addition, early and medium-term T cell-mediated immune response4 has been described in LT recipients. Compared to nontransplanted patients, LT recipients show a lower prevalence of anti-SARS-CoV-2 IgG antibodies 12 months after COVID-195 but the long-term cellular immunity to SARS-CoV-2 in these patients has not yet been assessed. The present study aimed to assess the long-term specific SARS-CoV-2 T cell-mediated immune response in LT recipients compared with non-transplant patients. Methods Study population Fifteen LT recipients and 15 non-transplanted controls who had confirmed COVID-19 in March–April 2020 were included at 12 months following COVID-19 diagnosis to determine SARS-CoV-2-reactive T cells and humoral responses. None of the patients received therapy with immunoglobulins or convalescent plasma transfusions, active chemotherapy, or SARS-CoV-2 vaccination. LT recipients with clinical operational tolerance and controls receiving any immunosuppressive treatment were excluded. All of the patients had been enrolled in previous studies5 including a large cohort of LT recipients and controls matched using a propensity score according to demographic features, comorbidities (diabetes, arterial hypertension, and cardiovascular disease), hospital admission, requirement of mechanical ventilation, and admission to the intensive care unit. COVID-19 was confirmed by a real-time reverse transcription-polymerase chain reaction assay6 on nasopharyngeal swab samples. Severe COVID-19 was defined as admission to the intensive care unit or requirement of mechanical ventilation. Demographic and clinical data were obtained from reliable electronic medical records. The study was performed according to the principles of the Declaration of Helsinki and European Union Regulation 2016/679 and was approved by the local research ethics committee. All patients provided written informed consent before their inclusion in the study. Sample collection Peripheral venous blood was collected from each patient at Hospital General Universitario Gregorio Marañón. Serum samples were recovered from anticoagulant-free tubes after being allowed to clot at room temperature and then centrifuged for 10 min at 800×g. The recovered serum was cryopreserved in small aliquots at −80 °C until use. Freshly EDTA-anticoagulated blood was shipped at room temperature to the Hospital Universitario Puerta de Hierro Majadahonda, and peripheral blood mononuclear cells (PBMCs) were isolated by density gradient centrifugation within 4 h of collection. Samples shipped for cellular assays were anonymized and blinded to patient status until statistical analysis was performed. In vitro stimulation of SARS-Cov-2 reactive T cells Fresh PBMCs were stimulated with overlapping peptide pools (PepTivator peptide pools; Miltenyi Biotec, Cologne, Germany) covering the complete sequence of proteins M and N or the immunodominant sequence domains of protein S. PBMCs were seeded at a density of 5 × 106 cells/cm2 in U-bottom 96-well plates in TexMACS™ (Miltenyi Biotec) culture medium containing 1ug/ml of proteins M, N, S, or a mixture of all three proteins (M + N + S). Each experiment included negative and positive controls for stimulation, consisting of PBMCs in complete medium alone or with a polyclonal stimulator of human effector/memory T cells (Cytostim; Miltenyi Biotec), respectively. Cells were harvested after 16 h at 37 °C and 5% CO2, and culture supernatants were cryopreserved at −20 °C until use. Analysis of SARS-CoV-2- reactive T cells After culturing under the conditions described above, PBMCs were washed in PBS/2 mM EDTA/0.5% BSA and incubated with mouse anti-human antibodies anti-CD3-FITC (clone BW264/56), anti-CD137-PE (clone 4B4-1), anti-CD69-APC (clone FN50, all from Miltenyi Biotec), and anti-CD4-PerCp-Cy5.5 or anti-CD8-PerCp-Cy5.5 (BD Biosciences; Franklin Lakes, New Jersey, USA). Mouse anti-human isotype control-irrelevant antibodies were used as negative controls for staining. At least 30,000 CD3+CD4+ or CD3+CD8+ cells were acquired and analyzed using a FACSCalibur flow cytometer (BD Biosciences) with CELLQuest-Pro software. SARS-CoV-2 reactive T cells were considered as CD3+CD4+ or CD3+CD8+ T lymphocytes expressing CD137 and CD69 simultaneously. The percentage of reactive T cells was calculated by subtracting non-specific reactive T cells when PBMCs were cultured in media alone. The cut-off values for a positive response were set at the mean ± 2 standard deviation (SD) of reactive T cells when PBMCs were cultured without stimuli. Analysis of cytokine secretion after stimulation with SARS-CoV-2 peptides Interleukin (IL)-2, IL-4, IL-6, IL-10, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ were quantified in the culture supernatants by flow cytometry using the Cytometric Bead Array Human Th1/Th2 Cytokine Kit II (BD Biosciences) according to the manufacturer's instructions. Samples and standards were acquired using a FACSCalibur flow cytometer and analyzed using FCAP Array software (BD Biosciences). The final concentration of each cytokine was calculated by subtracting the concentration observed in the supernatant of cells cultured in the media alone. Assessment of SARS-CoV-2-specific antibodies SARS-CoV-2 IgG antibodies targeting protein N were detected in serum samples with chemiluminescence (SARS-CoV-2 IgG Reagent Kit, Abbott, Chicago, Illinois, USA)5 and antibodies targeting protein S with a quantitative chemiluminescent assay (SARS-CoV-2 IgG II Quant Reagent Kit, Abbott)5 using the ARCHITECT i2000 INSTRUMENT (Abbott). Statistical analysis Continuous variables are reported as median and interquartile range (IQR), and categorical variables as absolute numbers and percentages. Demographic and clinical characteristics of LT recipients and controls or of patients classified according to the reactivity of T cells against SARS-CoV-2 protein N were compared using the Fisher correction for the chi-square test or the Mann–Whitney U test, whenever appropriate. The Mann–Whitney U test was used to compare the percentage of reactive T cells and cytokine or IgG levels between the LT recipients and controls. Qualitative analyses of reactive T-cells against SARS-CoV-2 proteins and IgG prevalence were performed using Fisher's correction for the chi-square test. Correlations between the percentage of reactive T cells and cytokine or serum IgG levels were calculated using Spearman's test. Statistical analyses were made using SPSS version 25 (IBM SPSS Statistics), and graphs were generated using GraphPad Prism version 6.0 (GraphPad Software). All tested hypotheses were two-tailed and considered significant at P < 0.05. Results Study population and baseline characteristics The assessment of T cell-mediated and humoral immune responses was carried out at a median time of 11.9 (IQR 11.7–12.16) months after COVID-19 diagnosis without evidence of SARS-CoV-2 reinfection. Most patients were male (73.3%), with a median age of 63 years (Table 1 ). Arterial hypertension was the most frequent comorbidity (66.7%), and none of the patients had chronic obstructive pulmonary disease. All patients presented with symptomatic COVID-19. Eleven (73.3%) LT recipients and 14 (93.3%) controls required hospital admission, but only 4 patients (13.3%) presented with severe COVID-19. None of the LT recipients received interferon beta, and they were less frequently treated with lopinavir (p = 0.005) than were controls (Table 1). At the time of COVID-19 diagnosis, all LT recipients received chronic immunosuppression, mainly tacrolimus (n = 11; 73.3%), followed by mycophenolate mofetil (n = 7; 46.7%) and everolimus (n = 4; 26.7%). Twelve months post-infection, the majority of patients received tacrolimus (n = 11; 73.3%) and everolimus (n = 6; 40.0%) (Table 1).Table 1 Demographical and clinical characteristics of the study group. Table 1 LT recipients (n = 15) Immunocompetent controls (n = 15) p Age (years) 63 (43–66) 62 (47–72) 0.461 Sex (male) 11 (73.3) 11 (73.3) >0.99 Previous medical history Diabetes mellitus 5 (33.3) 7 (46.7) 0.710 Hypertension 9 (60.0) 11 (73.3) 0.700 ACE inhibitors or ARB 6 (40.0) 8 (53.3) 0.715 Clinical characteristics Non-severe COVID-19a 14 (93.3) 13 (86.7) >0.99 Hospital admission 11 (73.3) 14 (93.3) 0.330 Interval since transplantation (years) 5.57 (2.14–12) NA NA COVID-19 specific therapy Lopinavir 6 (40.0) 14 (93.3) 0.005 Interferon beta 0 10 (66.7) 0.001 Hydroxychloroquine 13 (86.7) 14 (93.3) >0.99 Azithromycin 9 (60.0) 4 (26.7) 0.114 Tocilizumab 1 (6.7) 1 (6.7) >0.99 Corticosteroids (boluses) 1 (6.7) 1 (6.7) >0.99 Immunosuppression at baseline Tacrolimus 11 (73.3) NA NA Cyclosporine 1 (6.7) NA NA Mycophenolate 7 (46.7) NA NA Corticosteroids (maintenance) 1 (6.7) NA NA Everolimus 4 (26.7) NA NA Immunosuppression at month 12 Tacrolimus 11 (73.3) NA NA Tacrolimus trough levels (ng/mL), n = 11 3.7 (1.9–4.7) NA NA Cyclosporine 0 NA NA Mycophenolate 3 (20.0) NA NA Corticosteroids (maintenance) 0 NA NA Everolimus 6 (40.0) NA NA Everolimus trough levels (ng/mL), n = 6 3.25 (2.9–4.9) NA NA Data are expressed as the median (interquartile range) or n (%). ACE, angiotensin-converting enzyme; ARB, angiotensin II receptor blocker; NA, not applicable. a Severe COVID-19 was defined as the requirement for respiratory support or admission to the intensive care unit. SARS-Cov-2 reactive T cells The percentage of SARS-CoV-2 reactive T cells against viral proteins was calculated in gated CD4+ and CD8+ T cells (Fig. 1 ). The percentage of SARS-CoV-2 reactive T cells in PBMCs cultured in media alone was 0.02 ± 0.014% and 0.019 ± 0.014% in CD4+ and CD8+ T cells, respectively, and the cut-off value for a positive response was set at 0.048% for CD4+ T cells and 0.047% for CD8+ T cells.Figure 1 Reactive CD4+ and CD8+ T cells against SARS-CoV-2 proteins. PBMC from 15 LT recipients and 15 controls were stimulated in vitro with proteins M, N, S, and a mixture of M + N + S for 16 h (A) Lymphocytes were gated according to FSC-height and SSC-height characteristics. Then, CD3+CD4+ or CD3+CD8+ T cells were selected, and SARS-CoV-2 reactive T cells were considered as those CD69+CD137+ cells in gated CD3+CD4+ or CD3+CD8+ cells (B) Example plots showing staining patterns of SARS-CoV-2 reactive T cells in gated CD3+CD4+ and CD3+CD8+ T cells in each culture condition (C) Percentage of reactive CD4+ and CD8+ T cells against each SARS-CoV-2 protein in 15 LT recipients and 15 controls. Bars show median percentage and error bars show interquartile range. Fig. 1 No differences were found in the percentage of reactive CD4+ (31.1 ± 13.9% and 24.3 ± 7%; p = 0.172) or CD8+ (35.1 ± 12.8% and 37.7 ± 13.3%; p = 0.847) T cells between LT recipients and controls, respectively, when PBMC were cultured with the positive control of antigenic stimulation. All LT recipients and controls presented SARS-CoV-2 reactive CD4+ and CD8+ T cells when stimulated with a mixture of M + N + S proteins, and no differences between the two groups were found in the percentage of reactive T cells (Fig. 1). When analyzing the reactive T cells against each viral protein separately, the percentage of reactive CD8+ T cells was similar for the two study groups. However, LT recipients showed a higher percentage of CD4+ T cells reactive against S (p = 0.003) and M (p = 0.037) proteins than did the control group (Fig. 1). Considering reactive T cells in a qualitative trait, no differences were found between the percentage of LT recipients and controls with a positive response to each viral protein (Table 2 ). All patients showed a positive CD4+ and/or CD8+ T-cell response to at least one of the viral proteins analyzed. In addition, 15 patients (eight LT recipients and seven controls) showed a positive response of both CD4+ and CD8+ T cells to all three proteins. A higher proportion of positive responses was found in CD4+ T cells than in CD8+ T cells, and protein N induced the lowest proportion of positive responses in both CD4+ and CD8+ T cells (Table 2).Table 2 Detectable T cells reactive to SARS-CoV-2 proteins M, N and S. Table 2 All patients (n = 30) LT recipients (n = 15) Immunocompetent controls (n = 15) p Reactive CD3+CD4+ T cells Against protein M 29 (96.7) 15 (100) 14 (93.3) >0.99 Against protein N 25 (83.3) 12 (80) 13 (86.7) >0.99 Against protein S 30 (100) 15 (100) 15 (100) >0.99 Reactive CD3+CD8+ T cells Against protein M 28 (93.3) 13 (86.7) 15 (100) 0.483 Against protein N 17 (56.7) 9 (60) 8 (53.3) >0.99 Against protein S 23 (76.7) 12 (80) 11 (73.3) >0.99 Data are expressed as n (%). Two LT recipients and one control failed to show a positive response to protein N in both CD4+ and CD8+ T-cells. To explore potential risk factors for a lower or null response to protein N, we compared demographic and clinical data of patients with both reactive CD4+ and CD8+ T cells [double positive (DP)] response (eight LT recipients and seven controls) and patients who did not show a DP response to protein N. All variables considered were similar for patients with and those without a DP response (Table 3 ), although LT recipients receiving tacrolimus tended to present a non-DP response to protein N (p = 0.077).Table 3 Demographical and clinical characteristics of the study group according to T cell response to SAR-Cov-2 protein N. Table 3 DP response (n = 15) No DP response (n = 15) p Age (years) 63 (44–69) 63 (43–66) 0.539 Sex (male) 13 (86.7) 9 (60.0) 0.215 Previous medical history Diabetes mellitus 7 (46.7) 5 (33.3) 0.710 Hypertension 9 (60.0) 11 (73.3) 0.700 ACE inhibitors or ARB 5 (33.3) 8 (60.0) 0.272 Clinical characteristics Non-severe COVID-19a 14 (93.3) 12 (80.0) 0.598 Hospital admission 13 (86.7) 12 (80.0) p > 0.99 COVID-19 specific therapy Lopinavir 8 (53.3) 12 (80.0) 0.245 Interferon beta 4 (26.7) 6 (40) 0.700 Hydroxychloroquine 13 (86.7) 14 (93.3) p > 0.99 Azithromycin 5 (33.3) 8 (53.3) 0.462 Tocilizumab 1 (6.7) 1 (6.7) p > 0.99 Corticosteroids (boluses) 0 (0.0) 2 (13.3) 0.483 Immunosuppression at baseline (n = 8) (n = 7) Tacrolimus 4 (50) 7 (100) 0.077 Cyclosporine 1 (12.5) 0 (0.0) p > 0.99 Mycophenolate 4 (50.0) 3 (42.9) p > 0.99 Corticosteroids (maintenance) 1 (12.5) 0 (0.0) p > 0.99 Everolimus 3 (37.5) 1 (14.3) 0.569 Immunosuppression at month 12 (n = 8) (n = 7) Tacrolimus 4 (40.0) 7 (100) 0.077 Tacrolimus trough levels (ng/mL), n = 11 3.6 (2.1–6.6) 4.2 (1.9–4.7) p > 0.99 Mycophenolate 2 (25.0) 1 (14.3) p > 0.99 Everolimus 3 (37.5) 3 (42.9) p > 0.99 Everolimus trough levels (ng/mL), n = 6 3.3 (2.1–6.6) 3.2 (2.7–3.2) p > 0.99 Interval since transplantation (years) 6.9 (3.2–18.9) 2.4 (1.7–8.4) p = 0.19 Data are expressed as the median (interquartile range) or n (%). DP: patients with both CD4+ and CD8+ positive response to protein N. a Severe COVID-19 was defined as the requirement for respiratory support or admission to the intensive care unit. Cytokine production after stimulation with SARS-Cov-2 peptides Interleukine-6 was widely detected above the maximum quantifiable level with the kit used, while IL4 concentration was below detectable levels in all culture conditions. Therefore, IL6 and IL4 production after stimulation with SARS-Cov-2 peptides was excluded from further analysis. Under almost all culture conditions, IL2, IL10, TNF-α, and IFN-γ levels were slightly lower in LT recipients than in controls, although the differences were not statistically significant (Fig. 2 ).Figure 2 Cytokine production after stimulation with SARS-CoV-2 proteins. Concentration (pg/ml) of IL2, IL10, TNF-α, and IFN-γ in culture supernatants after stimulation with proteins M, N, S, and M + N + S in 15 controls and 15 LT recipients. Bars show median percentage and error bars show interquartile range. Fig. 2 We then explored the correlation between cytokine levels and the percentage of CD4+, CD8+, or the sum of CD4+ and CD8+ (total) reactive T cells in all the included patients (n = 30). After stimulation with M + N + S proteins, a positive correlation was found between IFN-γ and the percentage of CD4+, CD8+, and total reactive T cells (Fig. 3 ). No correlation was found between cytokine levels and the percentage of reactive T cells to proteins M or S. Patients with a DP response to protein N presented higher production of IL2 (p = 0.033), TNF-α (p = 0.008), and IFN-γ (p = 0.049) than did patients without a DP response (Fig. 4 ).Figure 3 Correlation among cytokine levels and reactive T cells against SARS-CoV-2 proteins. Correlations between levels (pg/ml) of IL2, IL10, TNF-α, and IFN-γ in culture supernatants and reactive CD4+, CD8+ and total T cells after PBMC stimulation with proteins M + N + S. Median percentage of reactive T cells and IgG levels of all 30 patients included are shown. Fig. 3 Figure 4 Cytokine production in patients with and without a DP response to SARS-Cov-2 protein N. Concentration (pg/ml) of IL2, IL10, IFN-γ (left), and TNF-α (right) in culture supernatants after stimulation with protein N in patients with and without a positive response to both CD4+ and CD8+ T cells (DP). Bars show median percentage and error bars show interquartile range for all 30 patients included. Fig. 4 Prevalence and quantitative assessment of IgG antibodies against SARS-CoV-2 All patients, except for two LT recipients, showed anti-S IgG antibodies at 12 months following COVID-19 diagnosis. In contrast, only five (33.3%) LT recipients and eight (53.3%) controls presented anti-N IgG antibodies. No statistical significance was reached when comparing the prevalence or levels of anti-S and anti-N IgG antibodies of the LT recipients and controls (Table 4 ).Table 4 Incidence and levels of anti-spike and anti-nucleocapsid IgG antibodies according to study group. Table 4 LT recipients (n = 15) Immunocompetent patients (n = 15) p Anti-spike IgG detected; n (%) 13 (86.7) 15 (100.0) 0.483 Anti-spike IgG levels (UA/mL); median (IQR) 502.3 (169.5–984.2) 819.1 (480.9–2159.7) 0.370 Anti-nucleocapsid IgG detected; n (%) 5 (33.3) 8 (53.3) 0.462 Anti-nucleocapsid IgG levels; median (IQR) 0.8 (0.11–3.57) 1.75 (0.53–3.14) 0.232 Data are expressed as median (IQR) or n (%). Correlation between humoral and cellular response to SARS-CoV-2 No correlation was observed between the percentage of reactive T cells against protein N or S and levels of anti-N or anti-S IgG antibodies, respectively (Fig. 5 ), in all included patients (n = 30). Remarkably, all patients lacking anti-S IgG or anti-N IgG antibodies showed CD4+ T cells reactive to protein S or N, respectively, except for the two LT recipients and one control who failed to present T cells reactive against protein N.Figure 5 Correlation among reactive T cells and anti-IgG levels against SARS-CoV-2 at 12 months after COVID-19 diagnosis. Correlation between (A) reactive T cells against protein S and anti-S IgG levels, and (B) reactive T cells against protein N and anti-N IgG levels. Fig. 5 SARS-CoV-2 reinfections beyond one year Six patients (3 LT recipients and 3 controls) documented SARS-CoV-2 reinfection, all with asymptomatic or mild disease, at 11.2 ± 1.4 months following the study. All patients had received mRNA COVID-19 vaccines after the study, and reinfections were diagnosed at 5.7 ± 2.3 months after two (n = 1) or 3 (n = 1) doses in LT recipients and at 5.03 ± 3.02 months after one, two, or three doses in controls. No differences in cellular or humoral responses were found in patients and controls with or without SARS-CoV-2 reinfections. Discussion The limited data available indicate that the SARS-CoV-2 reactive cellular response in transplant recipients and in the general population is quite similar from soon after symptom onset7 , 8 up to six-eight months later.4 , 9 Our results show that the magnitude and functionality of cellular T-cell responses against SARS-CoV-2 were similar in LT recipients and non-transplant patients 12 months following COVID-19 infection. Remarkably, all LT recipients and controls presented T cells reactive against at least one viral protein analyzed (M, N, and S), and 50% of patients showed both CD4+ and CD8+ T cells reactive against all three viral proteins. As reported in several studies, most individuals that have recovered from COVID-19 present T-cell responses to proteins M, N, and S soon after diagnosis,7 with a stable SARS-CoV-2 T-cell repertoire of up to 3–8 months after symptoms4 , 10, 11, 12, 13 regardless of disease severity. Very few studies have analyzed the T-cell response to SARS-CoV-2 one year after infection. Zhang3 et al. found a T-cell response maintained over time in most patients at 6 and 12 months after disease onset. In a recent study performed in convalescent patients over a period of 1–11 months after COVID,14 specific response (T cell and IgG levels) was present in 90% of patients, but in contrast to our results, exposure to immunosuppressive drugs was an independent risk factor for the absence of a specific T-cell response. However, it is important to note that only 2 out of the 6 patients who were receiving immunosuppressive therapy were solid organ transplantation (SOT) recipients14; therefore, these results in the SOT population should be interpreted with caution. The percentage of reactive T cells for each viral protein tested was highly variable, and SARS-Cov-2 reactive CD4+ T cells exceeded CD8+ T cells against each protein, as widely described,1 , 4 , 7 , 11 , 12 in both LT recipients and controls. In addition, proteins M and S induced a higher percentage of reactive T cells than did protein N in both CD4+ and CD8+ T cells.9 , 15 While most patients presented a positive response of both CD4+ and CD8+ T cells against proteins M and S, only 50% of patients presented a DP response to protein N. However, no differences were found between patients with and those without a DP response against protein N with respect to demographic and clinical characteristics, COVID-19 severity, or time elapsed since transplantation or immunosuppressive regimen in LT recipients. In line with previous reports,1 , 3 , 7 , 12 , 15 we found polarization of reactive T cells towards a classic Th1 type, as considerable IL2, TNF-α, and IFN-γ were produced, while very little or no IL4 production was observed. Although we quantified cytokine levels in culture supernatants rather than directly analyzing their production by reactive T cells (such as intracellular staining or ELISpot), we suggest that these cytokines may be specifically secreted by T cells reactive to SARS-CoV-2 because of the positive correlation between the percentage of reactive T cells and IFN-γ levels. Moreover, the culture supernatants of patients with a DP response of both CD4+ and CD8+ T cells against protein N presented higher levels of IL2, TNF-α, and IFN-γ than did those of patients without a DP response. No significant differences were found between LT recipients and nontransplant patients in terms of specific humoral immunity. However, we cannot conclude that humoral immunity is similar in the two groups since lower prevalence and levels of anti-S and anti-N were found in LT recipients, although statistical significance was not reached, perhaps due to the small sample size. The proportion of patients with anti-S IgG antibodies one year after COVID-19 was very high in both study groups. In contrast, a lower prevalence of anti-N IgG antibodies was found, which is in agreement with previous studies.16 , 17 We did not find a correlation between the percentage of T cells reactive against N or S and anti-N or anti-S IgG antibody levels, as has also been reported in both SOT recipients and in the general population at 6 months following infection.4 , 12 , 13 , 18 Remarkably, the vast majority of patients lacking anti-N IgG antibodies presented CD4+ T cells reactive against N. These results show that most LT recipients and non-transplant patients who recovered from COVID-19 have SARS-CoV-2 specific CD4+ T cells, which, along with the reported memory B-cell repertoire,11 , 12 , 19 likely contribute to the development of protective immunity for at least 12 months after SARS-CoV-2 infection. Therefore, serodiagnostic tests alone cannot be considered strong indicators of protective immunity in COVID-19 convalescent patients, and T-cell assays might be considered to investigate the history of prior infection in epidemiological studies. Natural SARS-CoV-2 infection provides substantial and persistent immunologic protection to similar strains for a period of several months,20 and it is also cross-reactive with the highly mutated variant Omicron21 in most individuals. In this regard, none of unvaccinated patients included in this study suffered documented reinfection within one year. Indeed, reinfections were diagnosed about two years after prior infection and were probably due to Omicron since it was the predominant strain in Spain in this period. All reinfections presented with mild diseases, but since all patients were vaccinated after the study, we cannot discern whether protection from severe disease was attributable to natural immunity, vaccination, or both. This study has several limitations that should be considered when interpreting the results. First, the relatively small number of patients may have limited the ability to detect clinical associations with cellular response. Second, a high proportion of the patients required hospitalization but presented a non-severe disease. Therefore, it is possible that the spectrum of mild and asymptomatic COVID-19 as well as the most severe disease are not adequately captured, and our results could not be extrapolated to all forms of the disease. In addition, corticosteroid boluses were rarely administered to patients included in our study, although their use is now widespread in the acute phase of COVID-19. Although it is not yet clear whether corticosteroid boluses in the acute phase impair T-cell immunity in the long term, this possibility should be considered when interpreting our results. Furthermore, given the long interval since transplantation of the patients included in our study, our results should be interpreted with caution in regards to the first year post-transplantation; a higher degree of immunosuppression during the early post-transplant period theoretically could have led to differences in immunity against SARS-CoV-2 between transplant recipients and non-transplanted patients. Finally, since all patients received SARS-CoV-2 vaccination after the study, it is not possible to determine how long the protection of natural immunity lasts. However, long-term data regarding the T-cell immunity of unvaccinated patients are scarce; therefore, our results may be of interest for strategies against future SARS-CoV-2 variants that could be less covered by currently available vaccines. In conclusion, despite exposure to immunosuppression, LT recipients exhibited similar functional T-cell responses against SARS-CoV-2 to the reponses of matched non-transplanted individuals one year after a COVID-19 diagnosis. Funding This study has been supported by the grant “Beca de Investigación de la Fundación Sociedad Española de Trasplante Hepático (FSETH) 2020”. Maria J. Citores has received support from the “Catedra de Patrocinio UAM-Fundacion Lair” and Aránzazu Caballero-Marcos from the 10.13039/501100004587 Instituto de Salud Carlos III (Rio Hortega-CM19/00247). Data statement Data supporting the findings of this study are available from the corresponding author upon reasonable request. Declaration of competing interest None. ==== Refs References 1 Grifoni A. Weiskopf D. Ramirez S.I. Mateus J. Dan J.M. Moderbacher C.R. Targets of T cell responses to SARS-CoV-2 coronavirus in Humans with COVID-19 disease and unexposed individuals Cell 181 2020 1489.e15-1501.e15 2 Peng Y. Mentzer A.J. Liu G. Yao X. Yin Z. Dong D. Broad and strong memory CD4+ and CD8+ T cells induced by SARS-CoV-2 in UK convalescent individuals following COVID-19 Nat Immunol 2 2020 1336 1345 3 Zhang J. Lin H. Ye B. Zhao M. Zhan J. Dong S. One-year sustained cellular and humoral immunities of COVID-19 convalescents Clin Infect Dis 2021 ciab884 4 Fernández-Ruiz M. Olea B. Almendro-Vázquez P. Giménez E. Marcacuzco A. San Juan R. T cell-mediated response to SARS-CoV-2 in liver transplant recipients with prior COVID-19 Am J Transplant 21 2021 2785 2794 34092033 5 Caballero-Marcos A. Salcedo M. Alonso-Fernández R. Rodríguez-Perálvarez M. Olmedo M. Graus Morales J. Changes in humoral immune response after SARS-CoV-2 infection in liver transplant recipients compared to immunocompetent patients Am J Transplant 21 2021 2876 2884 33835707 6 Huang C. Wang Y. Li X. Ren L. Zhao J. Hu Y. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China Lancet 395 2020 497 506 31986264 7 Thieme C.J. Anft M. Paniskaki K. Blazquez-Navarro A. Doevelaar A. Seibert F.S. The magnitude and functionality of SARS-CoV-2 reactive cellular and humoral immunity in transplant population is similar to the general population despite immunosuppression Transplantation 105 2021 2156 2164 33988334 8 Candon S. Guerrot D. Drouot L. Lemoine M. Lebourg L. Hanoy M. T cell and antibody responses to SARS-CoV-2: experience from a French transplantation and hemodialysis center during the COVID-19 pandemic Am J Transplant 21 2021 854 863 33047493 9 Favà A. Donadeu L. Jouve T. Gonzalez-Costello J. Lladó L. Santana C. A comprehensive assessment of long-term SARS-CoV-2-specific adaptive immune memory in convalescent COVID-19 solid organ transplant recipients Kidney Int 101 2022 1027 1038 35124011 10 Bonifacius A. Tischer-Zimmermann S. Dragon A.C. Gussarow D. Vogel A. Krettek U. COVID-19 immune signatures reveal stable antiviral T cell function despite declining humoral responses Immunity 54 2021 340 354.e6 33567252 11 Sherina N. Piralla A. Du L. Wan H. Kumagai-Braesch M. Andréll J. Persistence of SARS- CoV-2-specific B and T cell responses in convalescent COVID-19 patients 6-8 months after the infection Med (NY) 2 2021 281 295.e4 12 Dan J.M. Mateus J. Kato Y. Hastie K.M. Yu E.D. Faliti C.E. Immunological memory to SARS-CoV-2 assessed for up to 8 months after infection Science 371 2021 eabf4063 13 Kirchner T. Heinrich S. Bonifacius A. Engel B. Ruhl L. Pink I. Reduced humoral but stable cellular SARS-CoV-2-specific immunity in liver transplant recipients in the first year after COVID-19 PLoS One 7 2022 e0276929 14 Konik M. Lindemann M. Zettler M. Meller L. Dolff S. Rebmann V. Long-term SARS-CoV-2 specific immunity is affected by the severity of initial COVID-19 and patient age J Clin Med 10 2021 4606 34640623 15 Thieme C.J. Anft M. Paniskaki K. Blazquez-Navarro A. Doevelaar A. Seibert F.S. Robust T cell response toward spike, membrane, and nucleocapsid SARS-CoV-2 proteins is not associated with recovery in critical COVID-19 patients Cell Rep Med 1 2020 100092 16 Fenwick C. Croxatto A. Coste A.T. Pojer F. André C. Pellaton C. Changes in SARS-CoV-2 antibody responses impact the estimates of infections in population-based seroprevalence studies J Virol 95 2021 e01828-20 17 Chia W.N. Tan C.W. Foo R. Kang A.E.Z. Peng Y. Sivalingam V. Serological differentiation between COVID-19 and SARS infections Emerg Microb Infect 9 2020 1497 1505 18 Schiffner J. Backhaus I. Rimmele J. Schulz S. Möhlenkamp T. Klemens J.M. Long-term course of humoral and cellular immune responses in outpatients after SARS-CoV-2 infection Front Public Health 9 2021 732787 19 Moore T. Hossain R. Doores K.J. Shankar-Hari M. Fear D.J. SARS-CoV-2-specific memory B cell responses are maintained after recovery from natural infection and postvaccination Viral Immunol 35 2022 425 436 35857310 20 Spicer K.B. Glick C. Cavanaugh A.M. Thoroughman D. Protective immunity after natural infection with severe acute respiratory syndrome coronavirus-2 (SARS- CoV-2) - Kentucky, USA, 2020 Int J Infect Dis 114 2022 21 28 34649001 21 Keeton R. Tincho M.B. Ngomti A. Baguma R. Benede N. Suzuki A. T cell responses to SARS-CoV-2 spike cross-recognize Omicron Nature 603 2022 488 492 35102311
PMC010xxxxxx/PMC10024305.txt	==== Front Food Environ Virol Food Environ Virol Food and Environmental Virology 1867-0334 1867-0342 Springer US New York 36933166 9551 10.1007/s12560-023-09551-6 Review Paper Application of Membrane Filtration to Cold Sterilization of Drinks and Establishment of Aseptic Workshop Hu Yunhao 1 http://orcid.org/0000-0002-4000-5709 Wu Wenbiao [email protected] 12 1 grid.263906.8 0000 0001 0362 4044 College of Food Science, Southwest University, No.2 Tian Shengqiao, Beibei, Chongqing, People’s Republic of China 2 grid.263906.8 0000 0001 0362 4044 Research Center of Grains, Oils and Foods Engineering Design, Industrial Research Institute, Southwest University, No.2 Tian Shengqiao, Beibei, Chongqing, People’s Republic of China 18 3 2023 2023 15 2 89106 19 11 2021 27 2 2023 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Aseptic packaging of high quality beverage is necessary and its cold-pasteurization or sterilization is vital. Studies on application of ultrafiltration or microfiltration membrane to cold- pasteurization or sterilization for the aseptic packaging of beverages have been reviewed. Designing and manufacturing ultrafiltration or microfiltration membrane systems for cold-pasteurization or sterilization of beverage are based on the understanding of size of microorganisms and theoretical achievement of filtration. It is concluded that adaptability of membrane filtration, especially its combination with other safe cold method, to cold- pasteurization and sterilization for the aseptic packaging of beverages should be assured without a shadow of doubt in future. Keywords Beverages Membrane Microorganism removal Theory and practice issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction Inadequate water intake can cause dehydration which subsequantly results in poor health or diseases (Perrier et al., 2013). The European Food Safety Authority Dietary Reference Values for the Adequate Intake of water was recommended to be 2.5 and 2.0 L/day, respectively for men and women from 14 years of age onward, and 2.1 and 1.9 L/day, respectively for boys and girls from 9 to 13 years of age (EFSA, 2010) while the Institute of Medicine of USA recommended higher water intake (3.7 and 2.7 L/day for males and females respectively) (Institute of Medicine, 2005). Solid foods intake can only contribute about 20% water so that 80% water should be provided by drinks (Popkin et al., 2010) including all kinds of liquids which are drinkable (Nissensohn et al., 2016). This promotes drinks production. About 1.6 trillion L (231 L/person/year) drinks were produced in 2009 (top 8 including tea (20.9%), bottled water (15.3%), milk (12.8%), carbonated soft drinks (12.5%), beer (11.2%), coffee (8.2%), still drinks (2.7%) and juices/nectars (2.6%) according to market share) (Neves et al., 2011). Although most drinks just mentioned above excepting bottled pure water also provide some other nutrients, the overwhelming majority of their component is water. Large quantity of water may cause the growth of microorganisms which spoil drinks quickly. Therefore, sterilization and proper packaging are essential for storing drinks with extended periods (or a targeted shelf life), which is a prerequisite to their marketability. To achieve this goal, sterilization (complete elimination of microorganism including spores) and aseptic packaging must be assured, which must be economical, relatively simple and capable of keeping nutritional or beneficial components and sensory properties as constant as possible. Sterilization by high temperature is traditionally used for producing drinks, e.g. milk, juices/nectars, teas, coffee and alcoholic drinks (Fellows, 2017; Pearce et al., 2012). Ultra-high temperature (UHT; heated at 130–150 °C for 1–2 s and then flash cooled to 70 °C) (Fellows, 2017) and high temperature at 120 °C with or without high pressure have usually be used. However, this technique has disadvantages, e.g. losses of B vitamins, vitamin C and other heat labile functional compounds (e.g. proteins) as well as adverse changes of sensory attributes, e.g. color, volatile aroma compounds and taste (Myer et al., 2016) in addition to high energy consumption. Therefore, cold sterilization of drinks has attracted extensive studies (Koutchma, 2009; Reineke et al., 2015). Physical [including ultraviolet irradiation, pascalization (high pressure), high intensity pulsed electric field, ultrasound, etc.] and chemical methods have been developed as cold sterilization methods. Although the physical methods can efficiently kill the vegetative cells of microbes, none of them alone is able to completely inactivate spores (Cho & Chung, 2020; Lopes et al., 2018; Lv et al., 2021; Modugno et al., 2020). The spores of bacillus species are not sterilized by hydrostatic high pressure (at 400 MPa) at room temperature (Takeo et al., 1994) so that its combination with other methods is proposed. Complete inactivation of spores by high intensity pulsed electric field is difficult to be achieved (Reineke et al., 2015). Chemical methods may be efficient to completely inactivate spores, but they are not safe for consumption and environment protection. Ultrasound alone is difficult to meet a 5-log reduction of microbes required by FDA (Rupasinghe & Yu, 2012). Ultraviolet irradiation may be efficient for sterilizing transparent drinks, but it has weakness, e.g. poor efficiency for cloudy drinks, cause of losses of nutrients, e.g. vitamins and quite harmful when it directly irradiates human body (Koutchma, 2009). Gamma or X-ray irradiation is usually not recommended for using in food industry because of safety concern. Ultrafiltration membrane has a pore size ranging from 0.001 to < 0.1 µm (McCarron et al., 2016) while microfiltration membrane has a pore size ranging from 0.1 to 10.0 µm (Ismail and Goh, 2014). An ultrafiltration or microfiltration membrane can reject particulates larger than its pore size with avoidance of causing adverse chemical or physical changes. Any pathogenic microbe has a certain size so that it can be removed by a membrane with a proper pore size. This means that ultrafiltration or microfiltration membranes with proper pore sizes have the potential of cold-sterilizing drinks. The aim of this paper is to review the application of membrane filtration to cold sterilization of drinks. This should provide the systematic knowledge about scientific basis and practical technology. Scientific Basis of Membrane Filtration to Remove Microorganisms For production of bottled water and other drinks, use of water is inevitable. It must be assured that pathogenic microorganisms are eliminated before proper packaging or consumption. Waterborne and airborne microorganisms are usually involved. In theory, the ability of removing microorganisms from drinks by a membrane depends on their sizes. For sphere-like shaped microorganisms, their removability by a membrane usually depends on their diameter. For rod-like microorganisms, their removability by a membrane is normally determined on their wide (the size being normally < that of length). Therefore, this section reviews the size of common water- or air-borne microorganisms. Size of Waterborne Microorganisms and their Removability Three types of pathogenic microorganisms have been identified to commonly exist in water. They are bacteria, viruses and parasites with their sizes being measured. Size of Waterborne Bacteria and their Removability by Membrane The size of bacteria is between that of parasites and viruses. Both bacillus and non- bacillus pathogenic bacteria can be found in water. Table 1 indicates that the size of bacillus bacteria ranges from 0.2 to 6 μm long by 0.2 to 1 μm wide depending upon different varieties. In addition to pathogenic microorganisms, those which are usually used for preserving or producing some kinds of drinks as probiotics or beneficial bacteria (lactic acid producing bacteria, e.g. Lactobacillus having a cell size of ≥ 0.3 µm in diameter or wide—the bacteria which produce lactic acids from sugars or acetic acid producing bacteria, e.g. Acetobacteraceae having a cell size of 0.6–0.8 µm by 1.0–4.0 µm—the bacteria which produce acetic acids from ethanol). This means that the ability of this kind of bacteria to penetrate a membrane with a certain pore size should be determined on their wide or diameter rather than their length. It appears to be that waterborne bacillus bacteria with size (width) less than 0.2 μm have not been reported.Table 1 Size of some waterborne bacteria, viruses and parasites Species Size Bacteria Burkholderia pseudomallei 2–5 μm long and 0.4–0.8 μm in wide (Dillon, 2014) Campylobacter jejuni, Campylobacter coli 0.2–0.5 μm long and 0.2–0.9 μm wide (Pielsticker et al., 2012) Escherichia coli 1–2 μm long or longer by 0.25–1 μm wide (Gu et al., 2016) Legionella spp. 0.3–0.9 μm wide by 2–20 μm long (Żbikowska et al., 2014) Non-tuberculous mycobacteria 0.5–5 μm in diameter (Bédard et al., 2016) Pseudomonas aeruginosa 0.5–1.0 μm wide by 1.5–5.0 μm long (Bédard et al., 2016) Salmonella enterica (serovar Typhimurium) 2–5 μm long by 0.5–1.5 μm wide (Andino & Hanning, 2015) Shigella spp. 0.3–1 μm wide by 1–6 μm long (PHE, 2015) Vibrio cholerae 1–3 μm long by 0.5–0.8 μm wide (Nazar-ul-Islam & Malik, 2015) Yersinia enterocolitica 0.5–0.8 μm wide by 1–3 μm long (Van Damme, 2013) Viruses Adenoviruses ca. 0.063 μm in diameter (Bondoc & Fitzpatrick, 1998) Enteroviruses 0.025–0.30 μm in diameter (Yates, 2014) Hepatitis A 0.027–0.032 μm in diameter (Konduru et al., 2009) Hepatitis E 0.027–0.034 μm in diameter (Kamar et al., 2014) Noroviruses 0.027 µm in diameter (Griffith, 2018) Sapoviruses ca. 0.030–0.038 µm in diameter (Robilotti et al., 2015) Rotavirus ca.0.07 µm in diameter (Oka et al., 2015) Parasites Protozoa Acanthamoeba spp. 25–40 μm (Marciano-Cabral & Cabral, 2003) Cryptosporidium parvum 0.4–0.6 µm (sporozoite) to 6 µm in diameter (mezoite) (Leitcha & He, 2011) Cyclospora cayetanensis 8–10 µm (Naito et al., 2009) Entamoeba histolytica 10–20 µm (Aguilar-Díaz et al., 2010) Giardia intestinalis 8–20 µm long by 5–16 µm wide (Zeibig, 2013) Naegleria fowleri 7-35 µm (Gutierrez, 2000; Claydon, 2017) Toxoplasma gondii 6–12 µm (Dumètre et al., 2013) Helminths Dracunculus medinensis 1.4- 2.7 cm long by 295–350 μm in wide (Eberhard et al., 2016) Schistosoma spp. ca. 254.9–500 µm long by 64 µm wide (cercariae) (Braun et al., 2018) or 70–175 µm long by 40–70 µm wide (egg) (Jing et al., 2018) Non-bacillus bacteria usually have a sphere-like shape, which are measured by diameter. Table 1 also shows that the size of the smallest water-borne non-bacillus bacteria is 0.5 μm in diameter. In practice, it should be noted that bacteria may be deformed by membrane so that they can transfer through the membrane with a pore size < their size (Gaveau et al., 2017). Furthermore, soft pathogens were reported to panetrate the membrane with a pore size < their size (Helling et al., 2017). This conclusion is supported by the report that a membrane with 0.1 μm pore size was suggested to assure the efficient removal of Burkholderia pseudomallei (Ralstonia pickettii) though the penetration of this kind of bacteria to a membrane with 0.2 (or 0.22) μm pore size was not observed by others (Sundaram et al., 1999). In conclusion, it can be predicted that a microfiltration membrane with its size at 0.1 μm or an ultrafiltration membrane may be useful for removing all kinds of water-borne bacteria. Size of Waterborne Viruses and their Removability by Membrane Viruses have the smallest size among three types of waterborne pathogenic microorganisms. Table 1 shows that the size of waterborne viruses including noroviruses ranges from 0.025 to 0.07 μm in diameter. However, virus size as small as 0.02 μm in diameter (Yin, 2015) and even 0.01 μm in diameter (Hai et al., 2014) were also reported. Ultrafiltration membrane with its pore size > 0.02 μm may not be able to remove the smallest viruses. Notwithstanding, ultrafiltration membrane with its pore size < 0.01 μm should be theoretically efficient for removing all kinds of viruses; the smaller the pore size of membrane, the higher the reliability of sterilization. Furthermore, a study on purification (or cold sterilization) of water indicated that the formation of a fouling (or named cake) layer may facilitate the removal of viruses by the membrane with a larger pore size (Chaudhry et al., 2015). On the other hand, too small size of ultrafiltration membrane can result in problem of serious fouling and low permeability of water or nutrient with a small molecular weight so that production efficiency is reduced. A study on cold sterilization of beer showed that precipitation of large particles, chemical interaction between solutes and membrane, absorption of small particles or solutes by inside wall of membrane pores, etc. may be associated with the mechanism of membrane fouling which may cause the following consquences: complete pore blocking, partial pore blocking, cake formation and internal pore blocking (Esmaeili et al., 2015). Therefore, selection of proper pore size of ultrafiltration membrane should always be necessary for obtaining a good balance of complete removal of viruses and reasonable production efficiency. It is reasonablly blieved that microfiltration membrane (pore size > 0.1 μm) may not be able to efficiently remove this kind of microorganisms. However, microfiltration may be used for the pretreatment of water to remove large microorganisms (including some viruses) before ultrafiltration so that fouling problem of membrane can be efficiently reduced. This kind (microfiltration/ultrafiltration) of filtration system found to be effective for the production of drinking water or other beverages (Ahmed et al., 2017). This kind of system may still need a pretreatment to tackle fouling problem depending upon varieties of beverages treated or the extend of contamination. For example, the use of coagulation reagents was reported to be effective for controlling the formation of fouling layer (Erdei et al., 2008; Jang et al., 2010). Size of Waterborne Parasites and their Removability by Membrane Parasites have the largest size among three types of waterborne pathogenic microorganisms. Table 1 indicates that the size of parasites ranges from 0.4 to 350 μm. Cryptosporidium parvum appears to be the smallest waterborne parasite, which has a size of 0.4 μm in the stage of sporozoite. Therefore, in theory, a microfiltration membrane with its pore size < 0.4 μm should be able to remove all kinds of water-borne parasites; the smaller the pore size of membrane, the higher the reliability of pasteurization or sterilization. Ultrafiltration membrane should theoretically be able to efficiently remove all kinds of water-borne parasites. Size of Waterborne Fungi and their Removability by Membrane The size of fungi found in water which may also contaminate beverages is quite large. Yeasts (e.g. Saccharomyces cerevisiae, a kind of fungi—producing ethanol from sugars; see Table 2 for its size) may also need to be removed for producing some packaged drinks, e.g. clear fruit juices and for preventing their spoilage (e.g. acidification of alcoholic drinks or fermentation of fruit juices to result in ethanol). The size of spores or conidia of most fungi or that of cells of some fungi is ≥ 1 μm in diameter or wide (Table 2). The spores or conidia, etc. may have cylindrical or elliptical shape, etc. so that their ability of penetrating a membrane with a fixed pore size normally determined on their diameter or wide rather than their length. Microfiltration membrane with its size < 1 μm should be able to remove spores or conidia, etc. of most fungi or cells of some fungi as well as whole part of them. Ultrafiltration membrane should theoretically be able to efficiently remove all kinds of water-borne fungi.Table 2 Size of some fungi as potential microbe-contaminants in water or air Genus Size Absidia 2.0–3.0 µm × 4.0–5.0 µm (cylindrical sporangiospore) (Nguyen et al., 2016) Alternaria 2.38–13.09 μm × 12.30–43.63 μm (spore size) (Abbo et al., 2018) Aspergillus ≥ 5 μm in diameter (spore), or ≥ 2.0 μm in diameter (conidia) (Kwon-Chung & Sugui, 2013) Blastomyces ≥ 1.5 μm in diameter (ascospore) (Lippman, 2001) Candida ≥ 1.5 μm in diameter (blastospore) (Whitley-Williams, 2006) Cladosporium ≥ 1.5 μm in diameter or wide (conidia) (Bensch et al., 2012) Cryptococcus 1–2 µm in diameter(spore) (Wang & Lin, 2012) Geotrichum ≥ 3 μm in diameter or wide (arthrospore) (Ochoa et al., 2015)or ≥ 2 μm in diameter or wide (chlamidospore) (San-Martin et al., 2008) Hansenula (Pichia) > 1 µm in diameter or wide (ascospore) (Kurtzman, 1987) Histoplasma > 1 µm in diameter (hypha) or ≥ 2 µm in diameter (microconidia) (Nosanchuk, 2016) Microsporum > 1.5 µm in diameter or wide (ascospore) (Dexter, 2003) Mucor ≥ 2 μm in diameter or wide (sporangiospore) (Álvarez et al., 2011) Penicillium ≥ 1.8 μm in diameter or wide (conidia) (Houbraken et al., 2011) Rhizopus ≥ 2.7 μm in diameter or wide (sporangiospore) (Hartanti et al., 2013) Rhodotorula ≥ 2 μm in diameter or wide (cell) (Chang & Wang, 2002) Saccharomyces ≥ 1 µm at the small diameter (cell) (Waites et al., 2013) Scopulariopsis ≥ 2 μm in diameter or wide (ascospore l) (Sandoval-Denis et al., 2013) Sporotrichum ≥ 1.4 μm in diameter or wide (blastoconidia) (Stalpers, 1984) Trichophyton ≥ 2 μm in diameter or wide (microconidia) (Armon & Cheruti, 2012) Trichosporon ≥ 2 μm in diameter or wide (arthroconidia) (Taj-Aldeen et al., 2009) In conclusion, the size of water-borne microorganisms ranges from 0.01 to 350 μm. Ultrafiltration membrane at a proper pore size (e.g. < 0.01 μm) should theoretically be able to remove all kinds of water-borne microorganisms whereas a microfiltration membrane with its size at 0.1 μm is suitable for removing bacteria with their size > 0.1 μm. It is suggested that pathogenic microorganism having the smallest size in water be determined before selection of a proper membrane for cold pasteurization or sterilization of water. Countermeasures for contaminations by "unexpected" pathogens may also be important for avoiding health risks in consumers (Amalfitano et al., 2018). This aspect has also be highlighted by other studies (Orhan et al., 2021; Beck et al., 2021). These can assure that the pasteurized or sterilized water can be directly used for producing bottled water (or for directly drinking) and preparation of other beverages. Size of Airborne Microorganisms and their Removability Table 2 indicates the size of airborne fungi. In addition, the size of many other airborne bacteria not indicated in the table is as follows: for example, size in term of diameter or wide, Staphylococcus (≥ 0.5 µm), Streptococcus (≥ 0.4 µm), Haemophilus (≥ 0.35 µm), Pasteurella (≥ 0.2 µm), Bordetella (≥ 0.2 µm), Franciscella (≥ 0.2 µm), Corynebacterium (≥ 0.25 µm), Borellia (≥ 0.2 µm), Treponema (≥ 0.09 µm), Neisseria (≥ 0.4 µm), Chlamydia (≥ 0.2 µm), Rickettsia (≥ 0.1 µm), Bacillus (≥ 0.1 µm), Clostridium (≥ 0.3 µm), Morganella (≥ 0.6 µm), Proteus (≥ 0.3 µm), Klebsiella (≥ 0.3 µm), Citrobacter, Coxiella (≥ 0.2 µm). The size of many airborne viruses has also been known, for example, Parvovirus B19, Rhinovirus, Coxsackievirus (Coxsackievirus 16 having a diameter of ca. 0.030 µm), Echovirus (0.024–0.030 µm), Hantavirus (0.070 to 0.350 µm), Togavirus (0.040 to 0.080 µm), Reovirus (0.050 to 0.080 µm), Adenovirus (0.070 to 0.100 µm), Orthomyxovirus (0.080 to 0.120 µm), Coronavirus (Coronavirus -19 having a size of 0.070 to 0.090 µm), Arenavirus (0.050 to 0.300 µm), Morbillivirus(e.g. Measles virus belonging to Paramyxovirus of the genus Morbillivirus having a size of 0.120 to > 0.300 µm), Respiratory Syncytial Virus (0.150 to 0.250 µm) and Poxvirus—Vaccinia (0.240 to 0.300 µm). Among these viruses, Parvovirus B19 and Rhinovirus have the smallest size, i.e. 0.018 µm while Paramyxovirus has the biggest size, i.e. 0.31 µm (Seregin et al., 2020; Kim et al., 2020; Flowers et al., 2016; Gong and Mita, 2014; Hepojoki et al., 2012; Utley et al., 2008; Rager et al., 2002; Doerfler, 1996; Couch, 1996; Baxby, 1996). Airborne microorganisms normally adhere to the particle matters in air (or named airborne dust). The adherence of microorganisms including bacteria, fungi and viruses to airborne dust can form bioaerosols having 0.5 to 50 μm size (Lee, 2011), which is much larger than that of the original bacteria, fungi and viruses. The airborne microorganisms may also contaminate drinks during their processing, filling and packaging. Therefore, removal of airborne microorganisms is very important for producing high quality drinks. For the avoidance of contamination by airborne microorganisms during the production of drinks, two kinds of approaches may be effective. One way is to remove them from contaminated drinks. Another way is to remove them from air to prevent drinks from contamination, i.e. establishing an aseptic workshop. According to the particle size of airborne microorganisms, they can even be removed by microfiltration membrane except for Treponema, Rickettsia and Bacillus. Ultrafiltration membrane at a proper pore size (e.g. < 0.01 μm) should theoretically be able to remove all kinds of airborne microorganisms, which should be suitable for cold sterilizing drinks which are contaminated by airborne microorganisms. It is suggested that pathogenic airborne microorganism having the smallest size be determined before selection of a proper membrane for cold pasteurizing or sterilizing a beverage as the end filtration of aseptic packaging. As the basis of selecting a proper membrane, the size of the largest nutritional or functional particle in beverage should also be determined. Summary of Relationship Between Nominal Pore Sizes of Membrane and Rejection of Microorganisms It should be noted that the norminal pore size of membrane provided by membrane manufacturers may be generally the size of the maximum pore of the membrane. Normally, a membrane with pore size distribution is manufactured and the rejection size of microorganism is determined on the maixum size of the membrane. At the initial stage of filtration, microorganisms with larger sizes may transmit the membrane with a smaller pore size due to deformation effects. This conclusion is supported by the report which described that an ultrafiltration membrane with a nominal pore size of 1 kDa was unable to completely remove norovirus from water (Matsushita et al., 2013). On the other hand, cake formation may result in the efficient removal of some microorganisms with their particle size smaller than the pore size of membrane though this process can reduce permeate flux. This conclusion is supported by the report which indicated that cake layer changed the cutt-off size of membrane (Zheng & Liu, 2007). Application of Membrane Filtration to Cold Sterilization of Drinks Ultrafiltration Membrane for Sterilizing Transparent Drinks Sterilization of Natural Water by Ultrafiltration Membrane Water from a natural source may contain certain amount of waterborne pathogenic microorganisms and airborne microorganisms derived from contamination. To assure that water is directly drinkable or applicable to drink or other sectors of food industry, its sterilization is inevitable. Nutrients in drinking water are minerals with molecular weights which are much smaller than the pore size of ultrafiltration membranes. Therefore, cold sterilization of natural water by ultrafiltration with a proper pore size is able to remove all kinds of microorganisms (see “2.” described above) with avoidance of losing valuable nutrients. Many studies on the cold sterilization of water by ultrafiltration can be found in literature. For example, a membrane made of polyvinylidene fluoride (PVDF)/ polyethersulfone (PES) blend was reported to be sufficient for cold sterilization of water (> 99.99% rejection of microbes) (Madaeni & Pourghorbani, 2013). The ultrafiltration membrane made of silica/polyvinyl alcohol was found to completely remove all microorganisms in water (Gan & Wu, 2020). Another study indicated that permeate of ultrafiltration membrane with 200 kDa separation contained virus particles (Bray et al., 2021), which may require the use of a membrane with smaller pore sizes for completely removing pathogens from water. A membrane with a pore size of 10,000 or 50,000 Da was reported to remove all microorganisms from apple juice and the quality attributes of the filtered juice resembled the untreated fresh juice except for slight browning of color (Ortega-Rivas et al., 1998). A pilot study using hollow fiber (Multibore PES membrane) for producing drinkable water for a long time was carried out (Molelekwa et al., 2014). The pore size of ultrafiltration membrane was 0.01–0.1 µm, which reduced total coliform from > 2419.2 CFU/100 mL (unacceptably high) to ca. 7 CFU/100 mL (< acceptable level of 10 CFU/100 mL recommended by WHO) and completely removed E. coli and enterococci. This means that cold sterilization of water by ultrafiltration membrane on an industrial scale is very likely feasible. The degree of fouling is dependent upon type of the material for making membrane and the extent of contamination; for example, if the membrane is made of PP, its permeability can decrease 68–97% after filtration of 150 L/m2 of water (Howe & Clark, 2002). The combination of coagulation/flocculation and ultrafiltration (using 0.1 µm ceramic membranes) for the treatment of drinking water (containing 39.55 CFU/mL total coliforms and 8.00 CFU/mL Escherichia coli) removed 99.0% of microorganisms with 368–626 L/hm2 average permeability as well as 14.07–23.55% Rm (intrinsic resistance of membrane), 5.18–75.65% Rf (fouling resistance of membrane) and 0.90–71.27% Rcp (concentration polarization resistance of membrane) depending upon variation of ∆P and coagulation reagents used (Bergamasco et al., 2011). On the other hand, proper fouling layer formed can facilitate the rejection of microorganisms, especially those with small sizes, such as virus. A membrane filtration system for cleaning water was reported to have a pore size capable of retaining most bacteria and incapable of rejecting virus, but achieve 3.3-log10 reduction of viral pathogens because of formation of a fouling (or named cake) layer (Verbyla and Rousselot, 2018). It was also reported that a 4- to 5- day fouling layer formed was able to result in a 1.6 log10 increase in removal (5.5–7.1-log10 reduction) of adenovirus (Chaudhry et al., 2015) whereas removing fouling layer immediately decreased the efficiency of removing virus (Lv et al., 2006). Therefore, proper balance between permeability and fouling may be important for the efficient sterilization of water by membrane filtration. Table 3 indicates that the efficiency of cold sterilization of ultrafiltration is better as compared with ultraviolet radiation, ozonation and chlorination. Ultrafiltration membranes with proper pore sizes can be efficient for cold-sterilizing water in drinking water industry and at home or public places. Also, it should be noted that the quality of raw water sources should significantly affect the efficiency of cold-sterilization and life-span of membranes used.Table 3 Comparison of indicative log10 removals of microorganisms from water between ultrafiltration and other cold sterilization methods (Collivignarelli et al., 2018) Microorganisms Ultrafiltration Ultraviolet radiation Ozonation Chlorination Viruses (Including Adenoviruses, Rotaviruses and Enteroviruses) > 3- > 6 > 1.0 adenovirus; > 3.0 enterovirus, hepatitis A virus 3.0–6.0 1.0–3.0 Bacterial Pathogens (Including Campylobacter) > 6.0 2.0– > 4.0 2.0–6.0 2.0–6.0 E. coli 5.5– > 6 2.0– > 4.0 2.0–6.0 2.0–6.0 Giardia > 6.0 > 3.0 - 0.5–1.5 Cryptosporidium > 6.0 > 3.0 - 0.0–0.5 Clostridium Perfringens > 6.0 - 0–0.5 1.0–2.0 Log 2 and log 3 correspond to 99% and 99.9% removals of microorganisms, respectively Sterilization of Clear Fruit Juice by Ultrafiltration Membrane All kinds of clear fruit juices should not contain any colloids with large particle sizes, such as proteins and polysaccharides. Otherwise, they are very likely to be turbid. Furthermore, the presence of proteins and polysaccharides such as pectin may lead to the formation of precipitates during storage. Therefore, these macromolecules should be removed so that clear fruit juices only contain the nutrients with small molecular weights. Ultrafiltration has been found to effectively remove such macromolecules as proteins and polysaccharides from fruit juices (Hounhouigan et al., 2014; Perreault et al., 2021; Toker et al., 2014). Since the particle size of some proteins and pectin is much smaller than 0.01 μm, the membrane able to completely remove them should be capable of removing all kinds of microorganisms. This means that clarification and cold-sterilization of fruit juices by ultrafiltration can be simultaneously achieved. Table 4 indicates the examples of studies on the application of ultrafiltration to cold sterilization of clear fruit juices. It is obvious that ultrafiltration is very effective on the removal of microorganisms. If the pore size of ultrafiltration membrane is small enough, microorganisms in clear fruit juices can be completely removed. Furthermore, ultrafiltration for removing microorganisms from apple juice on a pilot scale was studied (Li et al., 2006). This study compared ultrafiltration membranes made of ceramic and organic polymer. The logarithm value of bacteria reduction rate of ceramic membrane was found to be 9 whereas that of organic polymer membrane was only about 5.Table 4 Application of ultrafiltration (UF) to cold sterilization of clear fruit juices Ultrafiltration information Examples of drinks Jamun juice a Coconut waterb Pear juicec Apple juiced Pineapple juicee Scale (L) Laboratory Laboratory Pilot Pilot Pilot Membrane pore size 50 kDa < 0.01 µm 0.05 µm 0.1 µm 30 and 100 kDa Membrane material Polysulfone Polyethersulfone Ceramic Ceramic Polyethersulfone Membrane module form Hollow fibre Flat Tubular Tubular Hollow fibre Microbial removing efficiency Total plate count and yeast/mold count (log CFU/mL): 0, respectively Decrease from 4.16 to 0.0 log CFU/mL Total plate count decreased from 1.26 ± 0.36 × 105 to 1.12 ± 0.54 × 102 CFU/mL Logarithm value of bacteria reduction rate > 9 Completely removed aGhosh et al. (2019) bLamdande et al. (2020) cZhao et al. (2016) dLi et al. (2006) eLaorko et al. (2010) In addition, some studies proved that the sterilization of clear fruit juices by ultrafiltration is more effective than that by ultraviolet radiation while combination of both methods may improve sterilization effect. For example, study on white birch sap indicated that the total account of microbes was decreased from 1.6 × 104 CFU/mL to 2.0 × 102 CFU/mL by ultrafiltration using a membrane with 0.03 µm pore size, to 2.1 × 103 CFU/mL by ultraviolet irradiation, and to the level which was not detected during 40 days of storage at 4 or 25 °C by the combination of ultrafiltration and UV (Jeong et al., 2013). Storage studies also proved that ultrafiltration was effective on the cold sterilization of clear fruit juices. For example, banana juice filtered by ultrafiltration membrane can be stored up to 1 month without any deterioration (Sagu et al., 2014). Cold sterilization of bottle gourd (Lagenaria siceraria) juice by hollow fiber ultrafiltration was feasible since the quality of sterilized juice did not adversely alter after 8 weeks of storage (Mondal et al., 2016). Microfiltration Membrane for Sterilizing Drinks Sterilization of Fruit Juice Microfiltration may also play an important role in sterilization of drinks. The use of this method alone for sterilizing drinks may be feasible depending upon their initial status of microbial contamination and membrane pore size. This method may be used before the ultrafiltration of drinks for attenuating the fouling problem of membrane. In another way, this method may be used for removing microbial spores or microbes with large cell sizes before or after other cold sterilization methods such as high pressure homogenization of cloudy (or called opaque) drinks. A microfiltration system made by using the module of PSF (polysulfone) hollow fiber membrane with a pore size of 0.2 µm reduced total plat account of microorganisms from 1.53 × 104–3.34 × 106 CFU/mL to < 25 CFU/mL in pineapple juices, which had 37 L/m2h average permeability and decreased protein content (g/100 mL) from 0.409 to 0.375 (Laorko et al., 2010). When coconut water with 140 CFU/mL total plat account of microorganisms was filtered by first using a 0.8 µm followed by 0.45 µm cellulose nitrate membranes, the growth of microbes was not observed in the permeate stored in a glass bottle after 180 days of storage while the filtration processing increased total soluble solids (Mahnot et al., 2014). Positive results of membrane filtration for cold sterilization of juices from other fruits, e.g. mosambi (Nandi et al., 2009; Rai et al., 2006) and passion fruit (de Oliveira et al., 2012) have also been stated. Microfiltration for cold sterilizing pineapple juice on a pilot scale was found to be effective (Carneiro et al., 2002). The membrane with a pore size of 0.3 µm was able to reduce total microorganism of pineapple juice to the level that is safe for human consumption while content of its solid nutrients dissolved was not decreased. The solid particle size of opaque or cloudy fruit juices is much larger than the pore size of ultrafiltration membrane and the size of the smallest waterborne or airborne microorganisms (see “2.”). For example, cloudy apple juice is a suspension of particles with sizes of 0.25–5 µm (Tetik et al., 2013). Ultrafiltration can remove the solid particles from opaque fruit juices, which therefore is not a proper method for cold-sterilizing them. However, the solid particles of cloudy fruit juices can penetrate through microfiltration membranes with proper pore sizes. Therefore, microfiltration may be applicable to cold sterilization of cloudy fruit juices. Although the smallest pore size of microfiltration membrane is much larger than the size of the smallest waterborne or air borne microorganisms so that the complete removal of microorganisms by the microfiltration membrane may not be assured, the membrane with a proper pore size (e.g. 0.1 ≤ 0.4 µm) should completely remove the smallest spore of the waterborne or air borne microbes. Especially, as described in “Introduction”, such a cold method as high intensity pulsed electric field can effectively kill all microbes except for the inactivation of microbial spores. This means that the combination of microfiltration (for removing spores) with other methods of cold sterilization (inactivating vegetative cells) may be very effective for the sterilization of cloudy fruit juices. Some solid particles in a cloudy fruit juice may have larger sizes as compared with the smallest spore (0.4 µm, see Table 1) of some waterborne or airborne microbes so that they may be lost when the complete removal of the microbial spores is assured. This problem should be easily tackled by homogenizing all solid particles of the cloudy fruit juice to the size less than 0.4 µm, which also makes the cloudy fruit juice to be more stable. It should be noted that the size of solid particles in different varieties of cloudy fruit juices may vary a lot. Therefore, the measurement of size of solid particles in the cloudy fruit juice going to be sterilized is necessary before the designation of a proper microfiltration membrane. Milk Mainly, application of microfiltration to sterilization of milk has been studied because it contains quite large particles (water-protein-oil emulsion) which may be rejected by ultrafiltration. Ceramic membranes with a pore size of 0.8 µm in diameter effectively removed the spores of pathogenic bacteria which cannot be deactivated by high-temperature and short-time pasteurization from milk without loss of nutritional macromolecules, e.g. proteins (Tomasula et al., 2011). Microfiltration using a membrane with a pore size of 1.4 µm in diameter can reduce 5.63 log microorganisms and greatly extend the shelf life of skim milk while protein transmission is as high as ca. 99% (Dhineshkumar & Ramasamy, 2017; Elwell & Barbano, 2006). Removal of spores from skim milk by microfiltration on a pilot scale was also studied (Griep et al., 2018). This study indicated that two ceramic membranes with pore sizes of 1.2 and 1.4 µm reduced B. licheniformis spores (1.37 μm long and 0.64 μm wide) in skim milk from 6.98 to 2.41 log CFU/mL and from 6.11 to 3.94 log CFU/mL, respectively. Both membranes near-completely removed Geobacillus spores (1.59 µm in length and 0.81 µm in width). Protein losses from skim milk were ca.10% and ca.4% for membranes with pore sizes of 1.2 and 1.4 µm, respectively. This level of protein loss may be acceptable considering the benefit (low cost of producing safer products) of microfiltration at a proper pore size to milk industry. Membrane Filtration for Cold Sterilization of Alcoholic Drinks For cold sterilization of beer, membrane filtration has also attracted scientist’s attention. The advantages of membrane filtration include guarantee of impeccably sterilizing permeate, improvement of productivity and complete removal of microbes with avoidance of negative effect on quality caused by traditional heat treatment method, etc. though disadvantages, e.g. fouling problem and detectable change in beer quality may occur. Recent study indicated that the quality of sterilized beer obtained by microfiltration using ceramic membrane could be a reliable substitution for the traditionally used sterilization method though the permeation flux was not quite ideal (Kazemi et al., 2013). Membrane filtration was reported to be an effective method for cold pasteurization or sterilization of Jujube wine while microfiltration had better production efficiency than ultrafiltration (Kang et al., 1998). Tuber ceramic membranes with pore sizes of 0.2–1.4 µm effectively removed microorganisms from apple cider with the avoidance of changes in pH and soluble solids (Zhao et al., 2015). Microfiltration has been applied to production of microorganism free beer on a commercial scale (Cimini, 2014). For solving the problem of fouling caused by large amounts of yeast cells, pretreatment by employing absorbent or centrifugation is helpful. Large quantities of macromolecules e.g. proteins unlikely exist in beer. Since trace amount of them may cause precipitates during storage, use of ultrafiltration membrane to remove them should be helpful for improving beer quality. Sterilization of Drinks by Membrane Filtration on an Industrial Scale Application of microfiltration or ultrafiltration to cold sterilization of drinks on an industrial scale has been extensively studied and applied in practice (de Oliveira et al., 2012; Dhineshkumar & Ramasamy, 2017; Karmakar & De, 2017). The schematic diagram of cold sterilization or pasteurization based on microfiltration or ultrafiltration is summarized in Fig. 1.Fig. 1 Schematic diagram of cold sterilization or pasteurization of some soft drinks or beverages by microfiltration or ultrafiltration. a Pretreatment might be coagulation, or sand filtration, or carbon filtration, or centrifugation, or their combination while other type of cold sterilization or pasteurization might be UV irradiation, or pascalization (high pressure), or high intensity pulsed electric field, or ultrasound and sometimes these pretreatments might not be necessary depending upon the purity of water source; b Pretreatment might not be necessary and ultrafiltration or UV irradiation may not be applicable; c Pretreatment might be centrifugation or might not be necessary while other type of cold sterilization or pasteurization might not be used and in most cases microfiltration might be enough; d Pretreatment might not be necessary and ultrafiltration or UV irradiation may not be applicable Adaptability of Membranes Hydrophobic membranes cannot be wetted spontaneously by water (Mulder, 1996). They must be pre-wetted usually by alcohols (e.g. ethanol) when they are used in filtering aqueous solutions. This appears to indicate that these membranes may have a quite limited potential in terms of sterilizing drinks. However, such treatments are required only at the initiation of use of the membranes. In other words, once wetted membranes can be used without any additional treatment until the end of their life. Therefore, the requirement of pre-wetting may not be a big issue when the membrane used has reasonably long lifetime. Membranes made of polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polypropylene (PP), polystyrene (PS) and polyvinyl chloride (PVC) are samples of this kind of membrane, which can be used to make micro- or ultra-filtration membranes. Hydrophilic membranes usually have good water permeability. They have a potential in terms of cold sterilization of drinks. Membranes made of polyethersulfone (PES), polysulfone (PSF), polyacrylonitrile (PAN), silica/polyvinyl alcohol and cellulose acetate (CA) are good samples of this kind of membranes (Carneiro et al., 2002; Ghosh et al., 2019; Karmakar & De, 2017; Mahnot et al., 2014). Especially, if membrane used for sterilization should be replaced frequently, then the hydrophilic polymeric membranes with limited long-term stability may be of choice as well because the effect of possible degradation of membrane is not likely to be prominent in relatively short operation time. Good chemical resistance of a membrane is necessary for treating alcohols and acids. For this reason, the use of ceramic membrane may be the best selection for sterilizing alcoholic or acidic drinks. Another advantage of ceramic membrane is that it is able to withstand the harsh conditions of high frequency cleaning (including backflushing) (Charcosset, 2021). On the other hand, ceramic membrane has the following major disadvantages: brittleness, low area to volume ratio, low selectivity in large scale and high production cost (Bolto et al., 2020). Some organic membranes currently and commercially available, such as PSF and PAN can be damaged by alcohols and acids so that their performance was degraded for a long term filtration operation (Shukla & Cheryan, 2003). The use of this kind of membranes for sterilizing alcoholic or acidic drinks for a long term potentially takes the risk of penetration of microorganisms through degraded membrane. However, there still have been extensive studies on application of this kind of membranes to the sterilization of alcoholic or acidic drinks. The application of membranes made of polypropylene and polyethersulfone having the same pore size (0.2 μm) to filtration of white wine was compared (Ulbricht et al., 2009). The results indicated that polyethersulfone strongly absorbed polyphenols and polysaccharides to develop a fouling layer, but polypropylene did not. A filtration system using poly(vinylidene fluoride) hollow fiber membranes was reported to withstand aggressive solutions for cleaning (El Rayess et al., 2011). Module and Material of Membrane Filtration Membrane For engineering purpose, proper assembly of membrane is important. Several kinds of membrane filter systems have been developed, which are shown in Fig. 2.Fig. 2 Different filter systems based on flat ultrafiltration or microfiltration membrane for sterilization or pasteurization of beverages. a flat membrane, b hollow fiber membrane, c tubular membrane (Cui et al., 2010) Organic membrane can be made into flat-sheet or hollow fiber form of structure because it is elastic and soft, which can also be made into tubular type of membrane. Inorganic membrane (e.g. ceramic membrane) is made into tubular form of structure to overcome its inflexibility and fragility. Flat-sheet ceramic membrane is also commercially available. Membranes are assembled into a module and then several modules are mounted on a rack, having the same feed and discharge pipeline. Nowadays, Plate and Frame Module (A in Fig. 2), Hollow Fiber Module (B in Fig. 2), Tubular Module (C in Fig. 2), Capillary Module and Spiral Wound Module have been developed. Most organic membranes are assembled into Plate and Frame Module, Spiral Wound Module or Hollow Fiber Module whereas inorganic membrane is assembled into Tubular Module or Capillary Module. One application sample is the cold sterilization of beer using a cross-flow systems based on hollow fiber module (Esmaeili et al., 2015). A comparison study found that hollow fiber module using 0.1 µm membrane was better for cold sterilization of coconut water than that using 0.2 µm microfiltration and ultrafiltration membranes (Laorko et al., 2017). The ability of a plate and frame module using microfiltration membrane to remove bacteria and spores from beer was reported in a literature (Shekin, 2021). A tubular module using 1.4 µm membrane reduced the total mesophilic microflora about 4 Log and 2 Log from ovine milk and bovine milk, respectively (Panopoulos et al., 2020). Spiral Wound and Hollow Fiber Modules pack membranes with the highest area per unit volume whereas Plate and Frame or Tubular Module packs membrane with the lowest among all kinds of membrane modules. The characteristics and prices of different membrane modules are shown in Table 5, which usually vary with the variation of original materials used for making the membrane.Table 5 Characteristics and prices of different membrane modules commonly used (Zirehpour & Rahimpour, 2016) Items Name of module HFM PFM SWM CM TM Packing density High Low Intermediate Intermediate Low Cleaning Difficult Easy Intermediate Easy Easy Pressure drop High Intermediate Intermediate Intermediate Low Operationunder high pressure Upto 6.9 MPa Upto > 0.7 MPa Upto 6.9 MPa Upto 0.7 MPa Upto > 0.7 MPa Restriction of membrane form Yes No No Yes No Manufacturing cost Low High Moderate Moderate High HFM hollow fiber module, PFM plate and frame module, SWM spiral wound module, CM capillary module, TM tubular module Materials most commonly used for making ultrafiltration or microfiltration membranes and their characteristics are shown in Table 6. The membranes shown are commercially available and they do not have health or environmental safety problems. The removal of bacteria from water by PVDF with 0.2, 0.1 or 0.05 µm was found to be 100% (Ghayeni et al., 1999). PES with 0.45–0.65 µm pore sizes was reported to be good for removing yeasts from beer (van der Sman et al., 2012) and cold-sterilizing peapple jiuce (Carneiro et al., 2002). The feasibility of PAN for cold-sterilizing tender coconut water was indicated (Karmakar & De, 2017). Membranes made of other materials with the pore size of microfiltration for removing bacteria from fruit juices and other drinks were summarized in literature (Liu et al., 2022; Conidi et al., 2020; Bhattacharjee et al., 2017; Cassano, 2015). Preparation of an ultrafiltration or microfiltration membrane using silica/polyvinyl alcohol is also feasible (Ran & Wu, 2017).Table 6 Materials most commonly used for making ultrafiltration membranes and their critical characteristics Membrane material Characteristics pH range Maximum inflow pressure Maximum operating temperature Adaptable membrane form PAN 3–9 0.3 MPaa 50 °C Flat, hollow fiber, spiral wound PS 2–12 0.3 MPaa 90–95 °C Flat, hollow fiber, spiral wound PSF 2–12 0.3 MPaa 80 °C Flat, hollow fiber, spiral wound PES 1.5–13 0.3 MPaa 80 °C Flat, hollow fiber, spiral wound PVC 3–9 0.3 MPaa 80 °C Flat, hollow fiber, spiral wound PVDF 2–11 0.3 MPab 140 °C Flat, hollow fiber, spiral wound Ceramic 1–14 Up to > 1.6 MPa Up to 200 °C Tubular PPO 2–11 Up to > 0.3 MPa Upto > 90 °C Flat, hollow fiber, spiral wound PFE 2–13 0.3 MPa 40 °C Flat, hollow fiber, spiral wound PTFE 1–14 Up to > 0.5 MPa Upto > 130 °C Flat, hollow fiber, spiral wound FEP 2–13 Up to > 0.3 MPa 90 °C Flat, hollow fiber, spiral wound PE 2–13 0.4 MPa 35 °C Flat, hollow fiber, spiral wound PP 2–13 0.3 MPa 90 °C Flat, hollow fiber, spiral wound CA 6–8 0.3 MPa 35 °C Flat, spiral wound PAN polyacrylonitrile, PS polystyrene, PSF polysulfone, PES polyethersulfone, PVC polyvinyl chloride, PVDF polyvinylidene fluoride, PPO polyphenylene oxide, PFE polyfluoroethylene, PTFE polytetrafluoroethylene, FEP fluorinated ethylenepropylene; PE polyethylene, PP polypropylene, CA cellulose acetate aInside-out pressure mode hollow fiber boutside-in pressure mode hollow fiber Modeling of Membrane Filtration Process The design, production, selection and operation of ultrafiltration or microfiltration systems need process modeling. Extensive studies on the modeling of membrane filtration can be found in literature (Khac-Uan & Félix, 2020; Krippla et al., 2020; Yusuf et al., 2016). Here, some models widely accepted are described. The production capacity of a membrane (i.e. amount of a beverage sterilized or pasteurized per hour per m2) is one of the critical index for its application in practice. The production yield of a selected membrane may be predicted by the following equation:1 V=AmxBfxt, In the equation, V is the total volume (m3) of beverage filtered during working time; t is working time (h) required for finishing filtration; Am is membrane area (m2); Bf is beverage flux (m3/m2.h) of membrane at a certain pressure, which may be established through experimentation. By using Eq. (1), the required area of membrane can be calculated according to a required amount (i.e. V) of sterilized or pasteurized beverages. Bf is dependent upon pore volume and polarity of membrane as well as properties e.g. viscosity, solutes concentration and pH of beverages at a certain pressure. Therefore, Bf is changeable during filtration process. Particles (i.e. from permeate) with their size < membrane pore size may deposit on or be absorbed by pore walls, which results in deceases in pore volume and subsequent reduction of Bf or production yield of sterilized or pasteurized beverage. Furthermore, selection of proper pore size of membrane is also important for achieving acceptable production capacity. Therefore, adequately desired production yield is achievable by selecting a proper membrane with an adequate filtering area, pore size, thickness and polarity. The fouling problem of membrane which greatly reduces production yield should not be ignored during stage of designing and establishing a membrane system for sterilizing or pasteurizing a beverage. Several studies have attempted to reduce fouling problem of membrane, which involve production of antifouling membrane (Wang et al., 2017), addition of reagents, e.g. enzyme or chitosan and centrifugation (Domingues et al., 2014). Furthermore, pretreatment of beverage by microfiltration or other method before ultrafiltration is usually implemented to tackle fouling problem. Furthermore, macromolecules (i.e. from concentrated solution) rejected by membrane may develop a fouling layer on the surface of membrane. The decrease in pore volume (DVp) during working time (t) is predicted by the following equation (Bowen et al., 1995):2 DVp=1/Pm0t+Ks/2-1. In the equation, Ks is standard blocking constant [m−1; which may be considered as combination of membrane intrinsically hydraulic resistance (RM) which is a fixed value for certain membrane unless significant change in the status of the membrane, concentration polarization resistance (RCP) and fouling resistance (RF)] while Pm0 is initial permeability of membrane. It would be worthwhile further investigating into the relationship between RM and Ks as well as that between RM and RF in future. Total Rm changes as filtration time is extended or number of runs is increased. Total Rm of a particular membrane for filtering a particular beverage can be established through experimentation. Establishment of RM and RF for filtering coconut water by hollow fiber membrane based on copolymer of PN has been well described (Karmakar & De, 2017). The authors supposed that total RM after Nth run may be modeled by the following equation:3 RM(N)=Rm(N-1)+Rirr(N)=ΔP/μwPmw(0). In the equation, RM(N) or Rm(N−1) is membrane resistance corresponding to Nth or N-1th run, respectively; Rirr(N) is irreversible membrane resistance after filtering at the end of Nth run which is associated with the irreversible change in membrane permeability because of irreversible membrane fouling or aging of membrane; ∆P is trans-membrane pressure; µw is water viscosity (0.9 × 10–3 Pa s at 30 °C, determined by a U-Tube viscometer); Pmw(0) is permeability of membrane at the end of Nth run. Trans-membrane pressure (∆P) required for beverage to permeate through a membrane can be calculated by the following equation (Sampath et al., 2014):4 ΔP=RmxPmxη. In the equation, Rm is beverage (or hydraulic) resistance (1/m) of membrane while η is beverage viscosity (Pa.s) at 25 °C. The sterilization or pasteurization efficiency (SE or PE; %) of membrane is another one of the critical index for its application in practice. SE or PE can be described by the following equation:5 SEorPE=Ocfu-Pcfu/Ocfu×100%=1-Pcfu/Ocfu×100%, In the equation, Ocfu is total number of bacterial colonies in culture medium of 1 mL original beverage while Pcfu is total number of bacterial colonies in culture medium of 1 mL pasteurized beverage by membrane. Application of Ultrafiltration Membrane to Aseptic Workshop Establishment of aseptic workshop can be a very good or efficient method to achieve the aseptic packaging of beverages. Critical unit of an aseptic workshop is an air purification system. Ultrafiltration membrane can be used for building the core part of the critical unit of an aseptic workshop. Figure 3 illustrates the critical part of structure of an aseptic workshop based on ultrafiltration membrane. Control of proper air pressure and seal are also critical for constructing the aseptic workshop. Generally, the air pressure of clean (or aseptic) area should be 5 Pa higher than that of non-clean (or non-aseptic) area and 10 Pa higher than that of outside of the aseptic workshop. The quantity of positive air volume required (Vair) can be calculated by using the following equation:6 Vair=kΣvL. Fig. 3 Critical constitute of sample of an aseptic workshop based on ultrafiltration membrane In the equation, k is the calibration constant which is determined on quality of seal of enclosure structure (normally being 1.1–1.3); v is the leakage air volume per unit length of the enclosure structure (m3/h.m); L is the total length of cracks of the enclosure structure. The air purification efficiency (APE) of the ultrafiltration membrane can be described by the following equation:7 APE=OACparticle-PACparticle/OACparticle×100%=1-PACparticle/OACparticle×100% In the equation, OACparticle is the concentration of dust particles in original air while PACparticle is the concentration of dust particles in the air purified by the ultrafiltration membrane. The prediction of air volume passing through a selected membrane during the stage of design can be done by the equation similar to Eq. (1). By using this equation, the area of membrane can be determined for producing required amount of purified air for establishing the clean (or aseptic) area of the aseptic workshop. The traditional classification of aseptic workshop and conditions for air purification is shown in Table 7.Table 7 Traditional classification of aseptic workshop and conditions for air purification Class Level 100 Level 1000 Level 10,000 Level 100,000 Particles (number/m3) ≥ 0.5 µm ≤ 3500 ≤ 35,000 ≤ 350,000 ≤ 3,500,000 ≥ 5 µm 0 0 ≤ 2000 ≤ 20,000 Living microbes (number/m3) Settling ≤ 1 ≤ 2 ≤ 3 ≤ 10 Floating ≤ 5 ≤ 75 ≤ 100 ≤ 500 Room temperature (°C) 20–24 20–24 20–24 18–26 Room humidity (%) 45–65 45–65 45–65 50–65 Percentage (%) of fresh air accounting for total air intake Vertical flow, 2%; Laminar flow, 4% 10% 20% 30% Airflow velocity through indoor section (m/s) Vertical flow, ≥ 0.25; Laminar flow, ≥ 0.25 – – – Air changes – ≥ 50 ≥ 25 ≥ 15 The ultrafiltration membranes suitable for pasteurizing clear beverages or drinking water may also suitable for removal of dust or fine particles from atmosphere since their size is normally larger than that of water borne microorganism. The stopper made of elastic rubber might not be needed when drinks are processed and packaged in an aseptic workshop. Conclusion Ultrafiltration or microfiltration membrane for cold-pasteurization or sterilization of beverages has been widely studied. The illustration of size of the smallest microorganism and theoretical achievement of solving fouling problem provide a solid scientific ground for designing and manufacturing ultrafiltration or microfiltration membrane systems for cold-pasteurization or sterilization of beverage. It is therefore concluded that adaptability of membrane filtration, especially its combination with other safe cold methods, to cold- pasteurization and sterilization of beverages on an industrial scale may be assured without a shadow of doubt in future. Data availability All data generated or analysed during this study are included in this published article (and its supplementary information files). Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Abbo AS Idris MO Elballa MA Hammad AM Siddig MARE Karlovsky P Genetic variability and host specialization in Alternaria alternata colonizing Solanaceous crops in Sudan Journal of Plant Protection Research 2018 58 3 246 256 Aguilar-Díaz H Díaz-Gallardo M Laclette JP Carrero JC In vitro induction of entamoeba histolytica cyst-like structures from Trophozoites PLoS Neglected Tropical Diseases 2010 4 2 e607 10.1371/journal.pntd.0000607 20169067 Ahmed I Balkhair KS Albeiruttye MH Shaiban AAJ Yonar T Importance and significance of UF/MF membrane systems in desalination water treatment Desalination 2017 IntechOpen Álvarez E Cano J Stchigel AM Sutton DA Fothergill AW Salas V Rinaldi MG Guarro J Two new species of Mucor from clinical samples Medical Mycology 2011 49 62 72 10.3109/13693786.2010.499521 20662633 Amalfitano S Levantesi C Garrelly L Giacosa D Bersani F Rossetti S Water quality and total microbial load: A double-threshold identification procedure intended for space applications Frontiers in Microbiology 2018 9 2903 10.3389/fmicb.2018.02903 30574126 Andino A Hanning I Salmonella enterica: Survival, colonization, and virulence differences among Serovars The Scientific World Journal 2015 2015 520179 10.1155/2015/520179 25664339 Armon R Cheruti U Environmental aspects of zoonotic diseases 2012 IWA Publishing Baxby D Baron S Chapter 69 Poxviruses Medical Microbiology 1996 4 University of Texas Medical Branch at Galveston Beck KL Haiminen N Chambliss D Edlund S Kunitomi M Huang BC Kong N Ganesan B Baker R Markwell P Kawas B Davis M Prill RJ Krishnareddy H Seabolt E Marlowe CH Pierre S Quintanar A Parida L Dubois G Kaufman J Weimer BC Monitoring the microbiome for food safety and quality using deep shotgun sequencing NPJ Science of Food 2021 5 3 10.1038/s41538-020-00083-y 33558514 Bédard E Prévost M Déziel E Pseudomonas aeruginosa in premise plumbing of large buildings Microbiologyopen 2016 5 6 937 956 10.1002/mbo3.391 27353357 Bensch K Braun U Groenewald JZ Crous PW The genus cladosporium Studies in Mycology 2012 72 1 401 10.3114/sim0003 22815589 Bergamasco R Konradt-Moraes LC Vieira MF Fagundes-Klen MR Vieira AMS Performance of a coagulation-ultrafiltration hybrid process for water supply treatment Chemical Engineering Journal 2011 166 483 489 10.1016/j.cej.2010.10.076 Bhattacharjee C Saxena VK Dutta S Fruit juice processing using membrane technology: A review Innovative Food Science Emerging Technologies 2017 43 136 153 10.1016/j.ifset.2017.08.002 Bolto B Zhang J Wu X Xie Z A review on current development of membranes for oil removal from wastewaters Membranes 2020 10 65 10.3390/membranes10040065 32272650 Bondoc LL Fitzpatrick S Size distribution analysis of recombinant adenovirus using disc centrifugation Journal of Industrial Microbiology and Biotechnology 1998 20 6 317 322 10.1038/sj.jim.2900529 Bowen WR Calvo JI Hernandez A Steps of membrane blocking in flux decline during protein microfiltration Journal of Membrane Science 1995 101 153 165 10.1016/0376-7388(94)00295-A Braun L Grimes JET Templeton MR The effectiveness of water treatment processes against schistosome cercariae: A systematic review PLoS Neglected Tropical Diseases 2018 12 4 e0006364 10.1371/journal.pntd.0006364 29608589 Bray RT Jankowska K Kulbat E Łuczkiewicz A Sokołowska A Ultrafiltration process in disinfection and advanced treatment of tertiary treated wastewater Membranes 2021 11 221 10.3390/membranes11030221 33804673 Carneiro L Sa IS Gomes FS Matta VM Cabral LMC Cold sterilization and clarification of pineapple juice by tangential microfiltration Desalination 2002 148 1–3 93 98 10.1016/S0011-9164(02)00659-8 Cassano A Basile A Charcosset C Integrated membrane processes in the food industry, Chapter 3 Integrated membrane systems and processes 2015 Wiley 39 60 Chang CW Wang PH Six Rhodotorula species from Taiwan Fungal Science 2002 17 12 23 26 Chaudhry RM Holloway RW Cath TY Nelson KL Impact of virus surface characteristics on removal mechanisms within membrane bioreactors Water Research 2015 84 144 152 10.1016/j.watres.2015.07.020 26231580 Cho WI Chung MS Bacillus spores: A review of their properties and inactivation processing technologies Food Science and Biotechnology 2020 29 11 1447 1461 10.1007/s10068-020-00809-4 33041624 Charcosset C Classical and recent applications of membrane processes in the food industry Food Engineering Reviews 2021 13 322 343 10.1007/s12393-020-09262-9 Cimini, A. (2014). Novel lager beer clarification and stabilization process using ceramic tubular microfiltration membranes. Ph. D Thesis, Tuscia Università. Claydon C Understanding Naegleria fowleri Watere Journal 2017 10.21139/wej.2017.012 Collivignarelli MC Abbà A Benigna I Sorlini S Torretta V Overview of the main disinfection processes for wastewater and drinking water treatment plants Sustainability 2018 10 86 10.3390/su10010086 Conidi C Castro-Muñoz R Cassano A Membrane-based operations in the fruit juice processing industry: A review Beverages 2020 6 18 10.3390/beverages6010018 Couch RB Baron S Orthomyxoviruses Medical Microbiology 1996 4 University of Texas Medical Branch at Galveston Cui ZF Jiang Y Field RW Cui ZF Muralidhara HS Chapter 1 - Fundamentals of pressure-driven membrane separation processes Membrane technology: A practical guide to membrane technology and applications in food and bioprocessing 2010 Elsevier De Oliveira RC Docê RC de Barros STD Clarification of passion fruit juice by microfiltration: Analyses of operating parameters, study of membrane fouling and juice quality Journal of Food Engineering 2012 111 432 439 10.1016/j.jfoodeng.2012.01.021 Dexter H Pathogenic fungi in humans and animals 2003 2 Marcel Dekker Dhineshkumar V Ramasamy D Review on membrane technology applications in food and dairy processing Journal of Applied Biotechnology and Bioengineering 2017 3 5 399 407 Dillon, M. J. (2014). Antibody interactions with the capsular polysaccharide of Burkholderia pseudomallei. Ph.D. Thesis, University of Nevada. Doerfler RW Baron S Chapter 67: Adenoviruses Medical microbiology 1996 University of Texas Medical Branch at Galveston Domingues RCC Ramos AA Cardoso VL Reis MHM Microfiltration of passion fruit juice using hollow fibre membranes and evaluation of fouling mechanisms Journal of Food Engineering 2014 121 73 79 10.1016/j.jfoodeng.2013.07.037 Dumètre A Dubey JP Ferguson DJP Bongrand P Azas N Puech PH Mechanics of the Toxoplasma gondii oocyst wall Proceedings of the National Academy of Sciences 2013 110 28 11535 11540 10.1073/pnas.1308425110 Eberhard ML Yabsley MJ Zirimwabagabo H Bishop H Cleveland CA Maerz JC Bringolf R Ruiz-Tiben E Possible role of fish and frogs as paratenic hosts of Dracunculus medinensis Chad Emerging Infectious Diseases 2016 22 8 1428 1430 10.3201/eid2208.160043 27434418 Erdei L Chang C Vigneswaran S In-line flocculation-submersed MF/UF membrane hybrid system in tertiary wastewater treatment Separation Science and Technology 2008 43 7 1839 1851 10.1080/01496390801974548 EFSA Panel on dietetic products, nutrition, and allergies (NDA). Scientific opinion on dietary reference values for water EFSA Journal 2010 8 1459 1507 Elwell MW Barbano DM Use of microfiltration to improve fluid milk quality Journal of Dairy Science 2006 89 1 E20 30 10.3168/jds.S0022-0302(06)72361-X 16527875 El Rayess Y Albasi C Bacchin P Taillandier P Raynal J Mietton-Peuchot M Devatine A Cross-flow microfiltration applied to oenology: A review Journal of Membrane Science 2011 382 1 19 10.1016/j.memsci.2011.08.008 Esmaeili S Peivasteh RL Mortazavian A Khosravi-Darani KK Sohrabvandi S Utilization of membrane systems in beer processing Journal of Paramedical Sciences 2015 6 2 15 Fellows PJ Food processing technology: Principles and practice, series in food science Technology and Nutrition 2017 Woodhead Publishing 563 578 Flowers EM Bachvaroff TR Warg JV Neill JD Killian ML Vinagre AS Brown S Almeida AS Schott EJ Genome sequence analysis of CsRV1: A pathogenic reovirus that infects the blue crab Callinectes sapidus across its trans-hemispheric range Frontiers in Microbiology 2016 7 126 10.3389/fmicb.2016.00126 26904003 Gan Y Wu W Application of composite ultrafiltration membrane in aseptic packaging industry of beverages Food and Fermentation Industries 2020 46 9 190 194 Gaveau A Coetsier C Roques C Bacchin P Dague E Causserand C Bacteria transfer by deformation through microfiltration membrane Journal of Membrane Science 2017 523 446 455 10.1016/j.memsci.2016.10.023 Ghayeni S Beatson PJ Fane AJ Schneider RP Bacterial passage through microfiltration membranes in wastewater applications Journal of Membrane Science 1999 153 1 71 82 10.1016/S0376-7388(98)00251-8 Ghosh P Garg S Mohanty I Sahoo D Pradhan RC Comparison and storage study of ultra-filtered clarified jamun (Syzygium cumini) juice Journal of Food Science and Technology 2019 56 4 1877 1889 10.1007/s13197-019-03648-2 30996423 Gong J Mita MM Activated Ras signaling pathways and reovirus oncolysis: An update on the mechanism of preferential reovirus replication in cancer cells Frontiers in Oncology 2014 4 167 10.3389/fonc.2014.00167 25019061 Griep ER Cheng Y Moraru CI Efficient removal of spores from skim milk using cold microfiltration: Spore size and surface property considerations Journal of Dairy Science 2018 101 9703 9713 10.3168/jds.2018-14888 30146287 Griffith DE Non-tuberculous mycobacterial disease: A comprehensive approach to diagnosis and management 2018 Humana Press Gu H Chen A Song X Brasch ME Henderson JH Ren D How Escherichia coli lands and forms cell clusters on a surface: A new role of surface topography Scientific Report 2016 6 29516 10.1038/srep29516 Gutierrez Y Diagnostic pathology of parasitic infections with clinical correlations 2000 Oxford University Press Hai FI Riley T Shawkat S Magram SF Yamamoto K Removal of pathogens by membrane bioreactors: A review of the mechanisms, influencing factors and reduction in chemical disinfectant dosing Water 2014 6 3603 3630 10.3390/w6123603 Hartanti AT Rahayu G Hidayat I Rhizopus species from fresh tempeh collected from several regions in Indonesia HAYATI Journal of Biosciences 2013 22 3 136 142 10.1016/j.hjb.2015.10.004 Helling A Kubicka A Schaap IAT Polakovic M Hansmann B Thiess H Strube J Thom V Passage of soft pathogens through microfiltration membranes scales with transmembrane pressure Journal of Membrane Science 2017 522 292 302 10.1016/j.memsci.2016.08.016 Hepojoki J Strandin T Lankinen H Vaheri A Hantavirus structure—molecular interactions behind the scene Journal of General Virology 2012 93 1631 1644 10.1099/vir.0.042218-0 22622328 Houbraken J Frisvad JC Samson RA Taxonomy of Penicillium section Citrina Studies in Mycology 2011 70 53 138 10.3114/sim.2011.70.02 22308046 Hounhouigan MH Linnemann AR Soumanou MM Van Boekel MAJS Effect of processing on the quality of pineapple juice Food Reviews International 2014 30 2 112 133 10.1080/87559129.2014.883632 Howe KJ Clark MM Fouling of microfiltration and ultrafiltration membranes by natural waters Environmental Science and Technology 2002 36 3571 3576 10.1021/es025587r 12214651 Institute of Medicine. (2005). Panel on dietary reference intakes for electrolytes and water: Dietary reference intakes for water, potassium, sodium, chloride. Ismail AF Goh PS Kobayashi S Müllen K Microfiltration membrane Encyclopedia of polymeric nanomaterials 2014 Springer Jang HN Lee DS Ko SO The effects of coagulation with MF/UF membrane filtration in drinking water treatment Desalination and Water Treatment 2010 19 1–3 138 145 10.5004/dwt.2010.1906 Jeong SJ Jeong HS Woo SH Shin CS Consequences of ultrafiltration and ultraviolet on the quality of white birch (Betula Platyphylla var japonica) sap during storage Australian Journal of Crop Science 2013 7 8 1072 1077 Jing J Hanna MG Zhang DY Szporn AH Dingle TC Answer to photo quiz: Schistosoma haematobium Journal of Clinical Microbiology 2018 56 e00737 e816 29695541 Kamar N Dalton HR Abravanel F Izopetb J Hepatitis E virus infection Clinical Microbiology Review 2014 27 1 116 138 10.1128/CMR.00057-13 Kang H Chang KS Min YK Choi YH Value addition of Jujube wine using microfiltration and ultrafiltration Korean Journal of Food Science and Technology 1998 30 5 1146 1151 Karmakar S De S Cold sterilization and process modeling of tender coconut water by hollow fibers Journal of Food Engineering 2017 200 70 80 10.1016/j.jfoodeng.2016.12.021 Kazemi MA Soltanieh M Yazdanshenas M Fillaudeau L Influence of crossflow microfiltration on ceramic membrane fouling and beer quality Desalination and Water Treatment 2013 51 4302 4312 10.1080/19443994.2013.769660 Khac-Uan D Félix S Artificial intelligence model for forecasting of membrane fouling in wastewater treatment by membrane technology Modeling in Membranes and Membrane‐based Processes 2020 10.1002/9781119536260.ch9 Kim JM Chung YS Jo HJ Lee NJ Kim MS Woo SH Park S Kim JW Kim HM Han MG Identification of coronavirus isolated from a patient in Korea with COVID-19 Osong Public Health and Research Perspectives 2020 11 1 3 7 10.24171/j.phrp.2020.11.1.02 32149036 Konduru K Nakamura SM Kaplan GG Hepatitis A virus (HAV) packaging size limit Virology Journal 2009 6 204 10.1186/1743-422X-6-204 19922643 Koutchma T Advances in ultraviolet light technology for non-thermal processing of liquid foods Food and Bioprocess Technology 2009 2 138 155 10.1007/s11947-008-0178-3 Krippla M Dürauera A Duerkop M Hybrid modeling of cross-flow filtration: Predicting the flux evolution and duration of ultrafiltration processes Separation and Purification Technology 2020 248 117064 10.1016/j.seppur.2020.117064 Kurtzman CP Two new species of Pichia from arboreal habitats Mycology 1987 79 3 410 417 10.1080/00275514.1987.12025398 Kwon-Chung KJ Sugui JA Aspergillus fumigatus—what makes the species a ubiquitous human fungal pathogen? PLoS Pathogens 2013 9 12 e1003743 10.1371/journal.ppat.1003743 24348239 Lamdande AG Mittal R Raghavarao KSMS Flux evaluation based on fouling mechanism in acoustic field-assisted ultrafiltration for cold sterilization of tender coconut water Innovative Food Science & Emerging Technologies 2020 61 102312 10.1016/j.ifset.2020.102312 Laorko A Li Z Tongchitpakdee S Chantachum S Youravong W Effect of membrane property and operating conditions on phytochemical properties and permeate flux during clarification of pineapple juice Journal of Food Engineering 2010 100 514 521 10.1016/j.jfoodeng.2010.04.039 Laorko A Li Z Youravong W Tongjitpakdee S Chantachum S Cold sterilization of coconut water using membrane filtration: Effect of membrane property and operating condition Journal of Applied Membrane Science & Technology 2017 10.11113/AMST.V7I1.56 Lee BU Life comes from air: A short review on bioaerosol control Aerosol and Air Quality Research 2011 11 921 927 10.4209/aaqr.2011.06.0081 Leitcha GJ He Q Cryptosporidiosis-an overview Journal of Biomedical Research 2011 25 1 1 16 10.1016/S1674-8301(11)60001-8 Li J Wang Z Ge Y Sun Q Hu X Clarification and sterilization of raw depectinized apple juice by ceramic ultrafiltration membranes Journal of the Science of Food and Agriculture 2006 86 1 148 155 10.1002/jsfa.2281 Lippman M Cohen BS McCammon CS Size-selective health hazard sampling Air sampling instruments 2001 ACGIH Press Liu X Wang W Fei Y Zhou Y Jin L Xing Z Effect of sterilization methods on the flavor of cold brew coffee Beverage Plant Research 2022 2 6 10.48130/BPR-2022-0006 Lopes RP Mota MJ Gomes AM Delgadillo I Saraiva JA Application of high pressure with homogenization, temperature, carbon dioxide, and cold plasma for the inactivation of bacterial spores: A review Comprehensive Reviews in Food Science and Food Safety 2018 17 532 555 10.1111/1541-4337.12311 33350128 Lv R Liu D Zhou J Bacterial spore inactivation by non-thermal technologies: Resistance and inactivation mechanisms Current Opinion in Food Science 2021 42 31 36 10.1016/j.cofs.2020.12.014 Lv W Zheng X Yang M Zhang Y Liu Y Liu J Virus removal performance and mechanism of a submerged membrane bioreactor Process Biochemistry 2006 41 299 304 10.1016/j.procbio.2005.06.005 32288591 Madaeni SS Pourghorbani R Preparation of PVDF/PES blend membranes for cold sterilization of water and milk Advances in Polymer Technology 2013 32 S1 E141 E152 10.1002/adv.20278 Mahnot NK Kalita D Mahanta CL Chaudhuri MK Effect of additives on the quality of tender coconut water processed by nonthermal two stage microfiltration technique LWT-Food Science and Technology 2014 59 1191 1195 10.1016/j.lwt.2014.06.040 Marciano-Cabral F Cabral G Acanthamoeba spp. as agents of disease in humans Clinical Microbiology Reviews 2003 16 2 273 307 10.1128/CMR.16.2.273-307.2003 12692099 Matsushita T Shirasaki N Tatsuki Y Matsui Y Investigating norovirus removal by microfiltration, ultrafiltration, and precoagulation-microfiltration processes using recombinant norovirus-like particles and real-time immuno-PCR Water Research 2013 47 15 5819 5827 10.1016/j.watres.2013.07.004 23880217 McCarron A Donnelley M McIntyre C Parsons D Challenges of up-scaling lentivirus production and processing Journal of Biotechnology 2016 240 23 30 10.1016/j.jbiotec.2016.10.016 27769802 Modugno C Peltier C Simonin H Dujourdy L Capitani F Sandt C Perrier-Cornet JM Understanding the effects of high pressure on bacterial spores using synchrotron infrared spectroscopy Frontiers in Microbiology 2020 10 3122 10.3389/fmicb.2019.03122 32082270 Molelekwa GF Mukhola MS Van der Bruggen B Luis P Preliminary studies on membrane filtration for the production of potable water: A case of Tshaanda rural village in South Africa PLoS ONE 2014 9 8 e105057 10.1371/journal.pone.0105057 25144640 Mondal M Biswas PP De S Clarification and storage study of bottle gourd (Lagenaria siceraria) juice by hollow fiber ultrafiltration Food and Bioproducts Processing 2016 100 1 15 10.1016/j.fbp.2016.06.010 Mulder M Basic principles of membrane technology 1996 2 Kluwer Academic Publishers Myer PR Parker KR Kanach AT Zhu T Morgan MT Applegate BM The effect of a novel low temperature-short time (LTST) process to extend the shelf-life of fluid milk Spring plus 2016 5 660 10.1186/s40064-016-2250-1 Naito T Mizue S Misawa S Nakamura A Isonuma H Kondo S Dambara T Yamamoto N Cyclospora infection in an immunocompetent patient in Japan Journal of Infectious Diseases 2009 62 57 58 Nandi BK Das B Uppaluri R Purkait MK Microfiltration of mosambi juice using low cost ceramic membrane Journal of Food Engineering 2009 95 4 597 605 10.1016/j.jfoodeng.2009.06.024 Nazar-ul-Islam HH Malik MW Review of trends in Cholera Air and Water Borne Diseases 2015 4 118 Neves, M. F., Trombin, V. G., Lopes, F. F., Kalaki, R., & Milan, P. (2011). World consumption of beverages. In The orange juice business. Wageningen Academic Publishers. Nguyen TTT Lee SH Bae S Jeon SJ Mun HY Lee HB Characterization of two new records of Zygomycete species belonging to undiscovered Taxa in Korea Mycology 2016 44 1 29 37 Nissensohn M Sánchez-Villegas A Ortega RM Aranceta-Bartrina J Gil Á González-Gross M Varela-Moreiras G Serra-Majem L Beverage consumption habits and association with total water and energy intakes in the Spanish population: Findings of the ANIBES study Nutrition 2016 8 232 Nosanchuk JD Broaddus VD Endemic mycoses Murray & Nadels Textbook of Respiratory Medicine 2016 Elsevier Ochoa JL Ochoa-Alvarez N Guzmán-Murillo MA Hernandez S Ascencio F Isolation and risk assessment of Geotrichum spp. in the white shrimp (Litopenaeus vannamei Boone, 1931) from culture ponds Latin American Journal of Aquatic Research 2015 43 4 755 765 10.3856/vol43-issue4-fulltext-14 Oka T Wang Q Katayama K Saif LJ Comprehensive review of human sapoviruses Clinical Microbiology Reviews 2015 28 32 53 10.1128/CMR.00011-14 25567221 Orhan F Demirci A Gormez A Carbonate and silicate dissolving bacteria isolated from home-made yogurt samples Annals of the Brazilian Academy of Sciences (An Acad Bras CienC) 2021 93 4 e20200002 10.1590/0001-3765202120200002 Ortega-Rivas E Zarate-Rodriguez E Barbosa-Canovas GV Apple juice pasteurization using ultrafiltration and pulsed electric fields Food and Bioproducts Processing 1998 76 193 198 10.1205/096030898532089 Panopoulos G Moatsou G Psychogyiopoulou C Moschopoulou E Microfiltration of ovine and bovine milk: Effect on microbial counts and biochemical characteristics Foods 2020 9 284 10.3390/foods9030284 32143320 Pearce LE Smythe BW Crawford RA Oakley E Hathaway SC Shepherd JM Pasteurization of milk: The heat inactivation kinetics of milk-borne dairy pathogens under commercial-type conditions of turbulent flow Journal of Dairy Science 2012 95 1 20 35 10.3168/jds.2011-4556 22192181 Perreault V Gouin N Bérubé A Villeneuve W Pouliot Y Doyen A Effect of pectinolytic enzyme pretreatment on the clarification of cranberry juice by ultrafiltration Membranes 2021 11 55 10.3390/membranes11010055 33466623 Perrier E Vergne S Klein A Poupin M Rondeau P Le Bellego L Armstrong LE Lang F Stookey J Tack I Hydration biomarkers in free-living adults with different levels of habitual fluid consumption British Journal of Nutrition 2013 109 1678 1687 10.1017/S0007114512003601 22935250 PHE. (2015). Identification of Shigella species. UK Standards for Microbiology Investigations. ID 20 Issue 3; Published in 2014, last updated in 2015b. https://www.gov.uk/uk-standards-for-microbiology-investigations-smi-quality-and-consistency-in-clinical-laboratories. Accessed 10 March 2021. Pielsticker C Glünder G Rautenschlein S Colonization properties of Campylobacter jejuni in chickens European Journal of Microbiology and Immunology 2012 2 1 61 65 10.1556/EuJMI.2.2012.1.9 24611122 Popkin BM D'Anci KE Rosenberg IH Water, hydration, and health Nutrition Reviews 2010 68 439 458 10.1111/j.1753-4887.2010.00304.x 20646222 Rager M Vongpunsawad S Duprex WP Cattaneo R Polyploid measles virus with hexameric genome length EMBO Journal 2002 21 10 2364 2372 10.1093/emboj/21.10.2364 12006489 Rai P Majumdar GC Sharma G DassGupt S Des S Effect of various cut-off membranes on permeate flux and quality during filtration of mosambi (Citrus sinensis (I.) Osbeck) juice Food and Bioproducts Processing 2006 84 213 219 10.1205/fbp.05181 Ran S Wu W A silica/polyvinyl alcohol membrane suitable for separating proteins Journal of Porous Materials 2017 24 469 476 10.1007/s10934-016-0282-0 Reineke K Schottroff F Meneses N Knorr D Sterilization of liquid foods by pulsed electric fields–an innovative ultra-high temperature process Frontiers in Microbiology 2015 6 400 10.3389/fmicb.2015.00400 25999930 Robilotti E Deresinski S Pinsky BA Norovirus Clinical Microbiology Reviews 2015 28 134 164 10.1128/CMR.00075-14 25567225 Rupasinghe, H. P. V., & Yu, L. J. (2012). Emerging preservation methods for fruit juices and beverages. Food Additive. InTech, Rijeka. Sagu ST Karmakar S Nso EJ Kapseu C De S Ultrafiltration of banana (Musa acuminata) juice using hollow fibers for enhanced shelf life Food and Bioproducts Processing 2014 7 9 2711 2722 Sampath M Shukla A Rathore AS Modeling of filtration processes—microfiltration and depth filtration for harvest of a therapeutic protein expressed in Pichia pastoris at constant pressure Bioengineering 2014 1 260 277 10.3390/bioengineering1040260 28955028 Sandoval-Denis M Sutton DA Fothergill AW Cano-Lira J Gené J Decock CA de Hoog GS Guarro J Scopulariopsis, a poorly known opportunistic fungus: Spectrum of species in clinical samples and in vitro responses to antifungal drugs Journal of Clinical Microbiology 2013 51 12 3937 3943 10.1128/JCM.01927-13 24025910 San-Martin A Orejarena S Gallardo C Silva M Becerra J Reinoso R Chamya MC Vergara K Rovirosa J Steroids from the marine fungus Geotrichum SP Journal of the Chilean Chemical Society 2008 53 1 1377 1378 10.4067/S0717-97072008000100011 Seregin A Yun N Paessler S Bennett JE Chapter: 167 Lymphocytic Choriomeningitis virus, Lassa virus, and the South American hemorrhagic fevers (Arenaviruses) Mandell, Douglas, and Bennett's principles and practice of infectious Diseases 2020 Elsevier 2177 2184 Shekin JJ Applications of ultrafiltration, reverse osmosis, nanofiltration, and microfiltration in dairy and food industry Extensive Reviews 2021 1 1 39 48 10.21467/exr.1.1.4468 Shukla R Cheryan M Stability and performance of ultrafiltration membranes in aqueous ethanol Separation Science and Technology 2003 38 7 1533 1547 10.1081/SS-120019091 Stalpers JA Revision of the genus Sporotrichum Studies in Mycology 1984 24 105 Sundaram S Auriemma M Howard G Brandwein H Leo F Application of membrane filtration for removal of diminutive bioburden organisms in pharmaceutical products and processes PDA Journal of Pharmaceutical Science and Technology 1999 53 4 186 201 10754712 Taj-Aldeen SJ Al-Ansari N Shafei SE Meis JF Curfs-Breuker I Theelen B Boekhout T Molecular identification and susceptibility of Trichosporon species isolated from clinical specimens in Qatar: Isolation of Trichosporon dohaense Taj-Aldeen, Meis & Boekhout sp Nov. Journal of Clinical Microbiology 2009 47 6 1791 1799 10.1128/JCM.02222-08 19321719 Takeo T Kinugasa H Ishihara M Fukumoto K Shinno T Yano T Matsuno R Nakamura K Application of sterilization technique by hydrostatic high pressure for green tea drink Developments in food engineering 1994 Springer 864 866 Tetik N Karhan M Turhan I Aksu M Oziyci HR A large-scale study on storage stability of cloudy apple juice treated by N2 and ascorbic acid Journal of Food Quality 2013 36 121 126 10.1111/jfq.12025 Toker R Karhan M Tetik N Turhan I Oziyci HR Effect of ultrafiltration and concentration processes on the physical and chemical composition of blood orange juice Journal of Food Processing and Preservation 2014 38 1321 1329 10.1111/jfpp.12093 Tomasula PM Mukhopadhyay S Datta N Porto-Fett A Call JE Luchansky JB Renye J Tunick M Pilot-scale crossflow-microfiltration and pasteurization to remove spores of Bacillus anthracis (Sterne) from milk Journal of Dairy Science 2011 94 4277 4291 10.3168/jds.2010-3879 21854901 Van Damme, I. (2013). Isolation and spread of enteropathogenic Yersinia spp. throughout the pork production chain. Ph.D. Thesis, Ghent University. Verbyla, M. E., & Rousselot, O. (2018). Membrane bioreactors. In J. B. Rose, & B. Jiménez-Cisneros (Eds.), Water and sanitation for the 21st century: Health and microbiological aspects of excreta and wastewater management (Global water pathogen project). (J. R. Mihelcic, & M.E. Verbyla (Eds.), Part 4: Management of risk from excreta and wastewater - Section: Sanitation system technologies, pathogen reduction in sewered system technologies), Michigan State University, E. Lansing, MI, UNESCO. 10.14321/waterpathogens.63 Ulbricht M Ansorge W Danielzik I König M Schuster O Fouling in microfiltration of wine: The influence of the membrane polymer on adsorption of polyphenols and polysaccharides Separation and Purification Technology 2009 68 335 342 10.1016/j.seppur.2009.06.004 Utley TJ Ducharme NA Varthakavi V Shepherd BE Santangelo PJ Lindquist ME Goldenring JR Crowe JE Respiratory syncytial virus uses a Vps4-independentbudding mechanism controlled by Rab11-FIP2 PNAS 2008 105 29 10209 10214 10.1073/pnas.0712144105 18621683 van der Sman RGM Vollebregt HM Mepschen A Noordman T Review of hypotheses for fouling during beer clarification using membranes Journal of Membrane Science 2012 396 22 31 10.1016/j.memsci.2011.12.051 Waites MJ Morgan NL Rockey JS Higton G Industrial microbiology: An introduction 2013 Wiley Wang L Lin X Morphogenesis in fungal pathogenicity: Shape, size, and surface PLoS Pathogens 2012 8 12 e1003027 10.1371/journal.ppat.1003027 23236274 Wang H Wang ZM Yan X Chen J Lang WZ Guo YJ Novel organic-inorganic hybrid polyvinylidene fluoride ultrafiltration membranes with antifouling and antibacterial properties by embedding N-halamine functionalized silica nanospheres Journal of Industrial and Engineering Chemistry 2017 52 295 304 10.1016/j.jiec.2017.03.059 Whitley-Williams P Hutto C Candida Congenital and perinatal infections: Infectious disease 2006 Humana Press Yates MV Percival SL Yates MV Williams DW Chalmers RM Gray NF Basic microbiology Microbiology of waterborne diseases: microbiological aspects and Risks 2014 Elsevier Yin, Z. (2015). Human adenovirus removal in wastewater treatment and membrane process. Ph.D. Thesis, Michigan State University. Yusuf Z Wahab NA Sahlan S Dynamic modelling and control of membrane filtration process International Journal of Nanotechnology 2016 13 10–12 748 10.1504/IJNT.2016.080356 Zhao D Lau E Huang S Moraru CI The effect of apple cider characteristics and membrane pore size on membrane fouling LWT-Food Science and Technology 2015 64 974 979 10.1016/j.lwt.2015.07.001 Zhao L Wang Y Hu X Sun Z Liao X Korla pear juice treated by ultrafiltration followed by high pressure processing or high temperature short time LWT-Food Science and Technology 2016 65 283 289 10.1016/j.lwt.2015.08.011 Zheng X Liu J Virus rejection with two model human enteric viruses in membrane bioreactor system Science in China Series B 2007 50 3 397 404 10.1007/s11426-007-0047-3 Żbikowska E Kletkiewicz H Walczak M Burkowska A Coexistence of Legionella pneumophila bacteria and free-living amoebae in lakes serving as a cooling system of a power plant Water Air and Soil Pollution 2014 225 2066 10.1007/s11270-014-2066-y 25132694 Zeibig EA Clinical parasitology: A practical approach 2013 2 Elsevier Zirehpour A Rahimpour A Visakh PM Nazarenko O Membranes for wastewater treatment Nanostructured polymer membranes 2016 New York Scrivener Publishing
PMC010xxxxxx/PMC10028437.txt	==== Front sppfe PFE Policy Futures in Education 1478-2103 SAGE Publications Sage UK: London, England 10.1177_14782103231158171 10.1177/14782103231158171 Editorial Higher education policy and management in the post-pandemic era Nguyen Andy Learning and Educational Technology (LET) Research Lab, Faculty of Education and Psychology, University of Oulu , Finland; Faculty of Information Technology and Electrical Engineering, University of Oulu , Finland Tran Ly Faculty of Arts and Education, Deakin University , Australia Duong Bich-Hang MLF Teachers College, Arizona State University , USA; University of Minnesota , USA University of Minnesota, United States 5 2023 17 3 2023 17 3 2023 21 4 330334 © The Author(s) 2023 2023 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. typesetterts10 ==== Body pmcThe aim of the special issue is to present studies and discuss higher education policy and management in the post-pandemic. The COVID-19 pandemic has had a significant impact on higher education institutions around the world, leading to changes in how universities operate, teach and manage (Ali, 2020). The widespread shift to remote learning and the financial strain caused by the pandemic have prompted many universities to re-evaluate their policies and management practices (Khong et al., 2022). Policymakers, institutions, educators and students have had to adapt to the new reality brought on by the pandemic and find new ways to continue education. Despite these efforts, many challenges remain, and the pandemic has highlighted the need for rethinking the management of higher education. These challenges include financial, operational, technological and wellbeing aspects, as well as issues related to the loss of international students, campus closures and border restrictions. While technology has provided some solutions, there is still much uncertainty about how to best respond to the pandemic and prepare for the post-pandemic period. One major area of concern for higher education policy and management in the post-pandemic era is the issue of funding. The pandemic has resulted in a significant loss of revenue for universities, as many have had to refund tuition and housing fees and have seen a decline in enrolment. To address this issue, universities may need to implement cost-cutting measures, such as reducing staff or consolidating programs. They may also need to explore new revenue streams, such as online education and partnerships with industry. An important issue is the ongoing shift to remote learning. The pandemic has accelerated the adoption of online education, and many universities have had to quickly adapt to this new mode of instruction (Khong et al., 2022; Agasisti and Soncin, 2021). However, remote learning has its own set of challenges, such as ensuring the quality and accessibility of online course materials and providing support for students who may be struggling with the transition. Higher education institutions will need to develop policies and management strategies to address these challenges. Moreover, the pandemic has highlighted the importance of addressing equity and inclusion in higher education. Remote learning has disproportionately affected low-income students and students from marginalized communities, who may lack access to reliable internet and technology. To address this, universities may need to provide additional support and resources for these students and develop policies to promote equity and inclusion in all aspects of their operations. The COVID-19 pandemic has had a significant impact on higher education policy and management. The funding crisis and the shift to remote learning have prompted many universities to re-evaluate their policies and management practices, and to focus on issues such as cost-cutting, revenue generation, quality and accessibility of online education, and equity and inclusion. Nevertheless, the changes from the pandemic have brought positive effects to some aspects in the education sector such as encouraging and boosting the digitalization in education and evolving novel models for learning and teaching with technology. The use of technology may reveal important metrics that have not been previously considered by educational stakeholders and policy makers (Nguyen et al., 2020). For example, the use of advanced analytics and AI tools may analyse the actions of not only those responsible for educational decisions, but also other stakeholders involved. These tools may identify new factors or patterns that are relevant to the topic under consideration. Henceforth, the studies in this special issue have considered the issues and challenges emerging from the COVID-19 pandemic and looked at policy implications for higher education in the post-pandemic. In this special issue, Mula-Falcón et al. (2022) introduce an overview of higher education policy during the pandemic from a Spanish perspective. The study examines the policies established during the pandemic period, outlining the key decisions made by universities in Spain. The results show the coordinated efforts of the university system and the strong emphasis on the values of in-person instruction. The present health crisis has also exposed the shortcomings of the education system and has brought attention to its future. The study also suggested university systems to start laying the groundwork for educational innovation and training educators to adapt to online learning. Finally, the article provides recommendations for policymakers to handle future crises. Tran et al. (2023) examine the impacts of COVID-19 and geopolitics on Australian international education from stakeholders’ perspectives and propose implications for the post-pandemic policies. The findings suggest that the combination of COVID-19, geopolitical issues and government responses have intensified the sense of crisis for universities and the international education sector, as their financial stability heavily relies on international students. The study provides evidence for the need of a reciprocal, collaborative, responsive and empathetic approach to international education in order to minimize geopolitical risks and ensure a more sustainable future for the sector. The research has implications for policymakers, universities and other stakeholders in addressing the challenges posed by the COVID-19 pandemic and geopolitics on the Australian international education sector and moving forward. Mai and Chau (2022) investigate the factors motivating international students to select their destination country and higher education institution to study. The loss of international students has been one of major issues facing higher education institutions during the pandemic and attracting international students in the post-pandemic is obviously an essential topic. The study uses the push-pull factors framework and a mixed-methods approach that combines both qualitative and quantitative methods to examine the phenomenon in higher education institutions in Vietnam, a developing country that has not been widely studied as a destination for international students. The research findings reveal that major push factors include a desire for new experiences, a poor economic outlook in the home country, and limited job prospects. At the national level, the strong economic prospects in Vietnam are the top pull factor whereas, at the institutional level, the university’s reputation and its Vietnamese Studies and language programs are the most significant pull factors that attract international students to study at the university. Based on these findings, recommendations are proposed for higher education institutions in Vietnam and other developing Asian countries to attract international students, taking into account the context of the ongoing COVID-19 pandemic. Nguyen-Anh et al. (2022) examine digital transformation in higher education, especially for online learning. Due to the impact of the COVID-19 pandemic, many universities had to shift to online learning in order to continue providing education to their students. From a comparative analysis of educational digital transformation in Singapore and Vietnam, the study investigates how students, educators and administrators perceive online learning. Using the Technology Acceptance Model (TAM) as a theoretical framework and a cross-country sample, the study examines the factors that influence the preference for online learning among university students and faculty members. The findings indicate that each group within the university is influenced by different factors, with students being most affected by their technical abilities, educators by the perceived usefulness of online learning, and administrators by the conditions of practice. Additionally, the study confirms the differences in preferences for online learning between the two countries through multi-group testing. Overall, this research adds to the knowledge on online education and has important implications for educational stakeholders and policymakers in the post-pandemic era. Phan and Pham (2023) closely examine the teachers’ emotions and regulation strategies during the pandemic thus proposing relevant implications for institutional policy and management. Prolonging social distancing had a significant impact on mental wellbeing of many people including teachers. Beyond that, the rapid shift to online teaching during the COVID-19 pandemic has even worsened the issue and brought new experiences for teachers that have not been widely studied. While coping with the effects of social distancing, teachers also had to maintain their work and spend efforts on adopting online teaching. The study conducted in-depth semi-structured interviews to examine the emotional experiences of language teachers at a university from a post-structuralist perspective on emotions. The study reveals that the unique pedagogical and technological features of online teaching presented new challenges and evoked various emotions, both positive and negative, for the teachers. Additionally, the teachers reported using various strategies to cope with the new situation, which the study refers to as ‘in-the-moment’ and ‘out-of-class’ emotion regulation. The research emphasizes the need for institutions to acknowledge and support teachers in terms of resources, policy and management in the ‘new normal’ situation, while also highlighting teachers’ ability to be self-reliant and manage their emotions. The article stresses the importance of recognizing teachers’ emotions as an integral aspect of the profession, regardless of whether the classroom is physical or virtual. Nguyen et al. (2022) look at the emotional aspects of students during the COVID-19 pandemic. In particular, the study utilized a large-scale survey from 2252 students to look into how emotional intelligence in university students is connected to their ability to handle crisis during the COVID-19 pandemic. The results showed that both positive and negative emotions played a role in mediating the relationship between students’ self-emotion appraisal and their resilience during the pandemic. Additionally, the ability to use emotions and regulate emotions also had an impact on resilience, with positive emotions having a direct and indirect effect on resilience. Implications for further research and practical applications in higher education were discussed. O’Dea and Zhou (2022) investigate policy concerns about university students’ online professionalism in the post-pandemic era in UK context. The study discusses the opportunities provided by the pandemic for experimenting with online teaching and learning, and how this experience can be valuable for higher education institutions in adopting blended learning in the future. However, it also highlights the emergence of new issues related to student behaviour during online learning, such as teaching to blank screens, students' inappropriate use of social media icons, languages and outfits. It argues that these issues have not been properly investigated and are not addressed by existing codes of conduct for face-to-face teaching. The study is based on semi-structured interviews with 20 academic staff working in UK universities, which provided insights into students’ unprofessional online behaviour as seen by tutors and the challenges they faced in managing it in formal online learning environments. The findings suggest that special attention needs to be paid to policy making regarding online learning and students' online professionalism. Ngo and Phan (2022) continue the discussion with the topic on quality assurance systems and relevant practices towards the ‘new normal’ in the post-crisis era. This paper discusses the impact of COVID-19 on quality assurance practices in higher education in Vietnam. It examines existing debates and challenges in quality assurance and accreditation activities and identifies emerging issues in quality assurance practices in the post-pandemic era. The paper provides a conceptual tool to analyse the quality assurance of the higher education system, using three dimensions of teaching and learning, inputs and outputs. It is based on a critical review and analysis of emerging policies and existing literature and provides practical implications and projections for the future direction of quality assurance in higher education. The paper aims to provide a timely insight into the process of policymaking and the implementation of quality assurance in higher education during a time of uncertainty, with the goal of building resilience to future crises. Finally, Celik et al. (2022) positively raise the discussion upon the opportunities for higher education in the post-pandemic era. The study highlights the role of technology in transforming higher education and particularly explores the potential of learning analytics tools to address challenges faced by higher education students, instructors and institutions during the COVID-19 pandemic for future implications. The study found that learners needed timely support and interaction, and experienced difficulty with time management. Instructors struggled with pedagogical knowledge for online teaching and assessment was a challenge. Institutions were not prepared for digital transformation and online teaching. In response to these challenges, learning analytics tools were used for monitoring, planning online learning, fostering engagement and motivation, facilitating assessment, increasing interaction, improving retention, and being easy to use. The study suggests that understanding the potential of learning analytics tools can provide insight into future higher education policies. In their efforts to understand challenges and opportunities arising from the recent COVID-19 pandemic, the authors of this special issue have carefully investigated the phenomenon from different aspects and contexts. We also express our gratitude to all reviewers for their valuable feedback and constructive comments on the manuscripts. The special issue hopes to provoke continued discussions from education stakeholders on what we could learn from the pandemics, both from the practical and theoretical perspectives, and how we should move forward with more resilience in the post-pandemic era. The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article. ==== Refs References Ali W (2020) Online and remote learning in higher education institutes: a necessity in light of COVID-19 pandemic. Higher Education Studies 10 (3 ): 16–25. Agasisti T Soncin M (2021) Higher education in troubled times: on the impact of Covid-19 in Italy. Studies in Higher Education 46 (1 ): 86–95. Celik I Gedrimiene E Silvola A , et al. (2022) Response of learning analytics to the online education challenges during pandemic: opportunities and key examples in higher education. Policy Futures in Education 14782103221078400 : 147821032210784. DOI: 10.1177/14782103221078401 10.1177/14782103221078401 Khong H Celik I Le TTT , et al. (2022) Examining teachers’ behavioural intention for online teaching after COVID-19 Pandemic: a large-scale survey. Education and Information Technologies: 1–28. DOI: 10.1007/s10639-022-11417-6 10.1007/s10639-022-11417-6 Mai TKK Chau NH (2022) Attracting international students to a developing Asian country: push–pull factors for a niche market, the case of a Vietnamese higher education institution. Policy Futures in Education. DOI: 10.1177/14782103221134186 10.1177/14782103221134186 Mula-Falcón J Cruz-González C Domingo Segovia J , et al. (2022) Review of higher education policy during the pandemic: a Spanish perspective. Policy Futures in Education 14782103221134188 : 147821032211341. DOI: 10.1177/14782103221134188 10.1177/14782103221134188 Ngo HN Phan AN (2022) COVID-19 and higher education in Vietnam: systematically rethinking the quality assurance system and practices towards the ‘new normal’ in post-crisis era. Policy Futures in Education 14782103221095924 : 147821032210959. DOI: 10.1177/14782103221095924 10.1177/14782103221095924 Nguyen A Gardner L Sheridan D (2020) Data analytics in higher education: an integrated view. Journal of Information Systems Education 31 (1 ): 61–71. Nguyen NN Nham TP Takahashi Y (2022) Relationship between emotional intelligence and resilience among university students during crisis. Policy Futures in Education 14782103221139620 : 147821032211396. DOI: 10.1177/14782103221139620 10.1177/14782103221139620 Nguyen-Anh T Nguyen AT Tran-Phuong C , et al. (2022) Digital transformation in higher education from online learning perspective: a comparative study of Singapore and Vietnam. Policy Futures in Education 14782103221124180 : 147821032211241. DOI: 10.1177/14782103221124181 10.1177/14782103221124181 O’Dea X Zhou X (2022) Policy concern about university students’ online professionalism in the post-pandemic era in UK context. Policy Futures in Education 14782103221088154 : 147821032210881. DOI: 10.1177/14782103221088154 10.1177/14782103221088154 Phan QA Pham TL (2023) Online teaching during the COVID-19 pandemic: Vietnamese language teachers’ emotions, regulation strategies and institutional policy and management. Policy Futures in Education. DOI: 10.1177/14782103231178644 10.1177/14782103231178644 Tran L Nguyen DTB Blackmore J , et al. (2023) COVID-19, geopolitics and risk management: Towards framing a reciprocal, coordinated, responsive and empathetic international education sector. Policy Futures in Education. DOI: 10.1177/14782103231163480 10.1177/14782103231163480
PMC010xxxxxx/PMC10031723.txt	==== Front Clin Oral Investig Clin Oral Investig Clinical Oral Investigations 1432-6981 1436-3771 Springer Berlin Heidelberg Berlin/Heidelberg 36947263 4940 10.1007/s00784-023-04940-4 Research Microbial adherence on vacuum-formed retainers with different surface roughness as constructed from conventional stone models and 3D printed models: a randomized controlled clinical trial Belayutham Sonia 1 Wan Hassan Wan Nurazreena [email protected] 1 Razak Fathilah Abdul 2 Mohd Tahir Norhidayah Nor zahidah 1 1 grid.10347.31 0000 0001 2308 5949 Department of Paediatric Dentistry and Orthodontics, Faculty of Dentistry, Universiti Malaya, Kuala Lumpur, Malaysia 2 grid.10347.31 0000 0001 2308 5949 Department of Oral and Craniofacial Sciences, Faculty of Dentistry, Universiti Malaya, Kuala Lumpur, Malaysia 22 3 2023 2023 27 6 32453259 21 6 2022 1 3 2023 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Objective This single center parallel, randomized controlled trial aimed to determine the propensity of microbial adherence on vacuum-formed retainers (VFRs) with different surface roughness imprints. Materials and methods Thirty-six patients debonded from fixed appliances at a teaching institution were allocated by block randomization stratified for gender to three groups [VFRs fabricated on conventional, fused deposition modeling (FDM) or stereolithography apparatus (SLA) working models]. Participants wore the VFRs for three months full-time followed by three months part-time. VFRs were collected after each follow-up for Streptococcus and yeast counts. Surface roughness was measured indirectly on the working models using a 3D optical surface texture analyzer. Blinding was not feasible due to appliance appearance. The trial was registered [NCT03844425 (ClinicalTrials.gov)] and funded by the Universiti Malaya Dental Postgraduate Research Grant (DPRG/14/19). Results Thirty participants (eleven conventional, ten FDM, and nine SLA) were analyzed after six dropped out. No harms were reported. Microbial counts between the groups were not significantly different. There were more microbes in the lower VFRs than upper VFRs (total count: p<0.05; effect size, 0.5 during full-time wear and 0.4 during part-time wear). SLA had significantly (p<0.05) smoother surface than FDM (effect size, 0.3) and conventional models (effect size, 0.5). Microbial adherence was not associated with working model surface roughness. Conclusion Microbial adherence on VFRs was not influenced by degree of surface roughness imprints from working models. Clinical relevance 3D printed models can be used to make VFRs. Lower VFRs tended to accumulate oral microbes, potentially increasing the oral health risk in the lower arch. Keywords Vacuum-formed retainers Surface roughness Fused deposition modeling Stereolithography apparatus Streptococcus Candida issue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction Oral appliances can alter the oral environment and promote changes in the oral microbiota [1]. The surfaces of orthodontic appliances can harbor microorganisms in the form of biofilm [2], leading to the onset of caries and periodontitis. The most common oral bacteria related to caries and periodontal disease such as chronic marginal gingivitis include streptococci, typically the S. mutans [3], S. sanguinis, and S. milleri [4]. Other microbes such as Candida have also been isolated in children with high caries prevalence [5] and patients with periodontal disease [6]. Adhesion and colonization of Candida in the oral cavity under a compromised condition may lead to candidiasis. Vacuum-formed retainers (VFRs), which are used to maintain the position of corrected dental alignment, are fabricated by heating polyvinyl chloride sheets followed by vacuum- or pressure-formed procedure over the working casts [7]. Its appearance has made it the more accepted type of removable retainer by patients compared to Hawley retainers [8]. Conventionally, the casts are made from stone or plaster, though three-dimensional (3D) printing technology such as fused deposition modeling (FDM) and stereolithography apparatus (SLA) have made it possible to reconstruct 3D image data of study models to 3D replicas from resins with sufficient strength and heat resistance for the vacuum-formed retainer (VFR) fabrication [9]. VFRs made on 3D printed models are as effective as conventionally made VFRs for retention. However, they are subtly different as the functional dental surfaces appear coarser corresponding to the imprints of striated 3D model surfaces [10]. Salivary bacteria of patients in the retention phase showed a general decrease in patients who wore VFR compared to those using bonded retainer and Hawley retainer, with VFR showing significant reduction after 13 weeks compared to baseline [11]. The design of VFR also makes it a conducive oral environment as it provides additional surface for colonization of microbes especially after prolong use, as early as 60 days after being issued [12]. An increased population of the aciduric microbes may increase the risk of decalcification if cariogenic diet is regularly consumed [13] and periodontal attachment loss [14], if oral hygiene is neglected. The fabrication of VFR on 3D printed model may produce surfaces with variable dental surface finishing, depending on the type of printing used [10]. There is possibility that a rough surface finishing of the VFR may support microbial adherence and, thus, lead to increased microbial load in the oral cavity [15]. An increase in microbial adhesion would potentially impose increased risk on oral health. In terms of duration for wear, a systematic review found no difference in full-time or part-time wear for VFR to prevent changes in arch width and arch length [16]. However, there is insufficient evidence in the risk of microbial adherence between full-time or part-time wear. This study aimed to determine the propensity of microbial adherence on VFRs with different surface roughness imprints. The objectives of this study were (1) to investigate the propensity for microbial adherence on VFRs, particularly with increasing surface roughness imprints as made from using different types of working models; (2) to compare microbial adherence between the upper and lower VFRs with different surface roughness; and (3) to compare microbial adherence on VFRs with different surface roughness between full-time and part-time wear. The null hypotheses were as follows: (1) there was no difference in microbial adherence on VFRs constructed on conventional models and 3D printed models; (2) there was no difference in microbial adherence between the upper and lower VFRs with different surface roughness; (3) there was no difference in microbial adherence on VFRs with different surface roughness between full-time wear and part-time wear. Methods Trial design This was a randomized controlled trial with three parallel assignments and allocation ratio of 1:1:1. This single center study was conducted at the Faculty of Dentistry, Universiti Malaya, Kuala Lumpur, Malaysia. The recruitment started from September 2019 until June 2020. The trial began in December 2019 and was completed in April 2021. Participants, eligibility criteria, and setting Patients ready for debond after fixed appliance treatment at Faculty of Dentistry, Universiti Malaya, were screened. The inclusion criteria were healthy patients with no systemic disease who were planned for VFRs for retention. The exclusion criteria were those in sectional or single arch fixed appliances treatment, planned for other retention types, smokers, and with systemic disease that may affect salivary flow. Participants were given the patient information sheet and a detailed explanation of the clinical trial. Participation was voluntary. Recruited participants gave written consent prior to commencement of the study. Interventions Upon debonding, three sets of upper and lower alginate impressions (Hydrogum 5, Zhermack, Italy) were taken to construct the post-treatment study model and two sets of working models. Working models were used to fabricate the standard VFRs and the first set of interventional retainers. In the conventional group, an additional set of alginate impressions was taken to cast another working model for the second interventional retainers. The standard VFRs were issued on the same day of the debonding appointment. Participants were instructed to wear the standard VFRs full-time. Fabrication of the working models The alginate impressions were disinfected before casting using green stone (Profilare 100, Dentona, Germany). The stone model contained all involved dentition and the alveolar process. The stone working models were scanned with a structured light scanner (Maestro 3D, Age Solutions, Inc., Italy) using the EasyDentalScan software (Age Solutions, Inc., Italy) [17]. The 3D images of the conventional models were saved as stereolithographic (.stl) files. The FDM working model was made using the Ultimaker S3 machine (Ultimaker, Zaltbommel, Netherlands) at a layer resolution of 60–150 microns, while the SLA working model was made using Formlab Form 3 machine (Formlab, Somerville, Massachusetts) at a layer resolution of 25 microns. Fabrication of the interventional vacuum-formed retainers The interventional VFR was made from a thermoformed material (Erkodur by Erkodent®, Erich Kopp GmbH, Pfalzgrafenweiler, Germany) with 1.0 mm thickness according to the manufacturer’s instructions. The foil was heated and pressed against the upper and lower models individually using an automated pressure-forming unit (Erkopress ES-200E by Erkodent®, Erich Kopp GmbH, Pfalzgrafenweiler, Germany). After it had been left to cool, the foil was removed from the model and trimmed using a straight handpiece and finishing burs. The retainer was trimmed until half of the occlusal surface of the last molar tooth covered and the marginal extension of the retainer was 1–2 mm buccal and 3–4 mm lingual to the gingiva margins. The sharp edges of the retainer were smoothened using sandpaper and cleaned. The upper and lower interventional retainers were then placed in a covered plastic container filled with antibacterial mouthwash that contained chlorhexidine digluconate 0.12% (Oradex, Pahang Pharmacy Sdn Bhd, Malaysia). The retainers were left to soak overnight before being issued to the participant the following day to ensure that the retainers were sterile [18, 19] at the beginning of each trial stage. The same procedure was repeated to construct the second interventional VFRs. The conventional group used the second set working model fabricated at debond. The FDM and SLA groups used the same working models that were used to fabricate the first interventional VFRs. Figure 1 shows the different types of working models.Fig. 1 Working models (top) and their respective vacuum-formed retainer (bottom). The working models were made from A conventional stone, B fused-deposition modeling 3D model, and C stereolithography apparatus 3D model. Interventional procedure Participants were reviewed one-week post-debond (T0). The standard VFRs were returned to the investigator (SB). The first interventional VFRs were issued, and participants were advised to wear the retainers full-time except during meals, brushing and cleaning of the appliance. They were supplied with a new retainer box and a new toothbrush to clean their appliances. Participants were reminded regularly to wear their retainers full-time for three months by SB, who sent reminder mobile messages once a week. Participants were reviewed at 3 months post-debond (T1). The first interventional VFRs were removed from participants’ mouth and placed in a covered plastic container filled with phosphate-buffered saline solution (PBS) before being transported to the microbiology laboratory. Participants returned the retainer box and toothbrush provided earlier. The second interventional VFRs were issued, and participants were advised to wear the retainers part-time for 10 h per day. They were given another new retainer box to keep their retainers when they are not used and a new toothbrush to clean their appliances. Participants were reminded regularly to wear their retainers 10 h per day for another 3 months by SB, who sent reminder mobile messages once a week. Participants were reviewed again at 6 months post-debond (T2). The appointments were in the morning so that patients were still wearing their retainers within the 10 h per day regime. The second interventional VFRs were removed from the participant’s mouth and placed in a covered plastic container filled with PBS before being transported to the microbiology laboratory. Participants were issued with the previously kept standard VFRs and advised to continue wearing the VFRs part-time. The appliance care and hygiene instructions were standardized for all the participants. They were instructed to clean their appliances using the new soft bristle toothbrush given during every review appointment and under running water only. Any type of soap or toothpaste was not allowed for cleansing of the appliances. Participants were informed not to use any type of mouthwash throughout the study period. They were also not allowed to soak their appliances in mouthwash or appliance cleanser. During part-time wear, the participants were asked to clean their appliances first using the soft bristle toothbrush and under running water. Then, the appliances were placed in a covered plastic container which was given during their review appointment and soaked in water only. Participants were also asked to clean the appliances again before wearing. Outcomes Primary outcome measure The primary outcome measure was microbial colony count on the VFRs. Clinical specimens and all microbial work were done under the laminar flow cabinet (ERLA CFM Series, Australia) to ensure sterile working environment and to prevent contamination of specimens and procedures. Brain heart infusion (BHI, Difco) agar and broth enriched growth media were used to determine the total microbial count. Mitis Salivarius Agar (MSA, Difco) was used for streptococci count and Sabouraud Dextrose Agar (SDA, Difco) for yeast count. All media in powder form was weighed appropriately according to the preparation manual, using an analytical balance (Mettler Toledo AJ100J, USA). The powder was dissolved in distilled water, boiled, and later sterilized at 121 °C for 15 min in an autoclave (HICLA VE HVE-50, Hirayama, Japan). Once cooled, the media were aseptically poured into petri dishes and labeled accordingly. Then, the sterile agar plates and broth media were packed and placed in a chiller (Mutiara, Malaysia) at 4 °C for later use. The upper and lower VFRs collected at T1 and T2 were placed into separate plastic containers filled with 150 ml of BHI broth using a sterile tweezer. The retainers were sonicated in a water bath (Grants SS-40-A2, Cambridge, England) and then vortexed for 60 s using a vortex mixer (Snijders Scientific, Holland) to dislodge any attached microorganisms. A 100 μl volume of broth from the plastic container containing the dislodged microorganisms was pipetted out and added into three microcentrifuge tubes, each containing 900 μl of BHI broth. Serial dilution was performed on the three microfuge tubes to produce three dilutions — 101, 102 and 103. This procedure was performed separately for both the upper and lower retainers. Then 50 μl of the suspension from each tube was pipetted out and inoculated on three separate BHI agar plates, three separate MSA agar plates, and three separate SDA agar plates. The plates were incubated in an incubator (Memmert, Germany) at 37 °C for 18 to 24 h. Following incubation, the plates with dilution that gave a colony forming unit (CFU) count between 30 and 300 for all the three types of agars were selected for enumeration. The growth population (CFU/mL) was calculated using the formula [20]:TotalgrowthpopulationCFUmL=NumberofgrowncoloniesDilutionfactorxVolumeusedmL The researcher (SB) was trained by a laboratory assistant (MAZ) to perform the microbial colony count. SB and MAZ, who was considered the gold standard, measured microbial colony count for inter-examiner reliability, while SB measured microbial colony count 2 weeks later for intra-examiner reliability. Intraclass correlation coefficient (ICC) performed using two-way mixed model for consistency resulted intra-examiner ICC of 0.897 (95% CI 0.821–0.938; p < 0.001) and inter-examiner ICC of 0.948 (95% CI 0.915–0.967; p < 0.001), which were considered good (ICC between 0.75 and 0.90) and excellent reliabilities (ICC above 0.90), respectively [21]. Secondary outcome measure The secondary outcome measure was the surface roughness value (Ra) of the working models used to fabricate the VFRs, recorded in micrometers (μm). It is an indirect measure of the surface roughness of the VFRs at the dental surfaces, which recorded the imprints of the working models during VFR fabrication when the softened heated VFR foils were pressed to cling closely to the working models before it hardened at normal temperature. Surface roughness analysis was performed using a 3D optical surface texture analyzer (InfiniteFocus, Alicona, Austria) on the working models of the first interventional VFRs (N=36). The working models were measured instead of the VFRs because the analyzer was not able to measure transparent objects like the VFRs. Since the rapid non-contact optical 3D measurement procedure reliably measures flat surfaces, the midpoint at the labial surface of the upper right central incisor was standardized as a reference point for measurement. The working model was placed on the stage and the reference point was scanned at 20 times magnification. Sample size calculation Sample size was determined based on a previous study [22] using GPower Software (Version 3.1.9.2). Sample size calculation was performed based on an alpha significance level of 0.05 and a beta of 0.20 to achieve 80% power to detect a significant difference between the groups. Based on the calculation, the total number of participants needed for the trial was 27 with a minimum of nine participants per group. After consideration of a dropout rate of 30 per cent, a total number of 36 participants were recruited for the trial. Randomization (random number generation, allocation concealment, implementation) Randomization was stratified by gender since women had shown better oral health behavior and oral hygiene compared to men [23], thus may affect microbial count if they were not fairly distributed between the groups. The proportion of male to female was set at 1:5 due to unequal gender proportions of uptake for orthodontic treatment at our institution [10]. Therefore, for a sample size of 36, the study would need to recruit six males and thirty females. Block randomization was performed for each stratified group using an online block randomization list generator (www.sealedenvelope.com) by another researcher (WNWH) who was not involved in the clinical procedure. Therefore, a list was generated for male participants with a block size of six and another list was generated for female participants with block sizes of three, six, and nine. The random allocation sequences were kept in sealed dark envelopes, labeled for gender, and numbered accordingly. Participants’ assignment to three groups, either conventional, FDM, or SLA group based on the random allocation sequence, was revealed when the envelopes were opened on the day of appointment for debonding. Participants were given a blinding code for analysis. Blinding This was an open label trial because blinding was not possible. Even though participants were not informed to which group the VFRs were made from, the dental surfaces of the VFRs had imprints of the working models, which had different surface finishing. The researcher (SB) who enrolled the participants was not aware of the group allocation or block sizes until the envelopes were opened on the day of debonding appointment. However, subsequently SB could not be blinded of the participants’ group allocation since the same researcher performed all the laboratory and clinical procedures. Statistical analysis SPSS was used to data analysis by another researcher (NMT) not involved in the laboratory and clinical procedures. The baseline data was tested for differences between the interventional groups. Chi-square test was used to compare for gender and ethnicity differences, while one way analysis of variance (ANOVA) was used to compare for age differences. Differences in compliance rates between groups at T1 and T2 were compared using chi-square test. Shapiro-Wilk test used to assess for normality of the outcome measures showed that the data was not normally distributed (p<0.05); thus, non-parametric analyses were applied. Microbial adherence between the interventional groups and surface roughness measurement of the working models of the groups were compared using Kruskal-Wallis test. If there were any statistically significant differences between the mean ranks, Dunn’s post-hoc test with Bonferroni adjustment used to determine which group or groups were different from the others [24]. The effect size was calculated (η2) where η2 = 0.01 was considered small, η2 = 0.059 was considered medium and η2= 0.138 was considered large [25]. Wilcoxon signed-rank test was performed to compare microbial adherence between upper and lower retainers and between full-time and part-time wear. Follow-up analysis on effect size (r) was calculated where r = 0.1 was considered small, r = 0.3 was considered medium, and r = 0.5 was considered large [25]. Kendall’s tau-b was used to test the association between surface roughness and microbial adherence. A value close to zero showed no association while a value close to 1 indicated strong association. For all analyses, a p value of less than 0.05 was considered significant. Results Participant flow The CONSORT flowchart (Fig. 2) shows the number of participants randomly allocated to each group, follow-up, and the number of dropouts and their reasons for dropping out.Fig. 2 Consort flowchart. (VFR-CONV, vacuum-formed retainer conventionally made on stone; VFR-FDM, vacuum-formed retainer made on fused-deposition modeling 3D model; VFR-SLA, vacuum-formed retainer made on stereolithography apparatus 3D model) Recruitment of participants began in September 2019. Treatment commenced in December 2019 and was completed in April 2021. A total of 42 patients were screened for eligibility, but six were excluded because four of them did not fulfill the inclusion criteria and the other two were not interested. Thus, a total of 36 participants had participated in the study. Baseline data Table 1 shows the baseline data for all three groups. Differences in the baseline gender, ethnicity, and age between the conventional group, FDM group, and SLA group were not statistically significant (p>0.05). The compliance rates between the groups at T1 and T2 were also not significantly different (p>0.05).Table 1 Participant characteristics Characteristics Distribution p value Total (N=30) Conventional (n=11) FDM (n=10) SLA (n=9) N (%) n (%) n (%) n (%) Gender Male 6 (16.7) 2 (18.2) 2 (20.0) 1 (11.1) 0.861π Female 30 (83.3) 9 (81.8) 8 (80.0) 8 (88.9) Ethnicity Malay 16 (53.3) 7 (63.6) 6 (60.0) 4 (44.4) 0.935π Chinese 14 (46.7) 4 (36.4) 4 (40.0) 5 (55.6) Age Mean (SD) Mean (SD) Mean (SD) Mean (SD) 24.13 (6.38) 26.00 (7.34) 23.40 (5.89) 22.67 (5.77) 0.476∞ Compliance N (%) n (%) n (%) n (%) T1 Compliant 21 (70) 7 (63.6) 7 (70.0) 7 (77.8) 0.790π Non-compliant 9 (30) 4 (36.4) 3 (30.0) 2 (22.2) T2 Compliant 28 (93.3) 11(100.0) 9 (90.0) 8 (88.9) 0.414π Non-compliant 2 (6.7) 0 (0) 1 (10.0) 1 (11.1) πChi-square test. ∞One-way ANOVA Numbers analyzed In total, 36 participants who fulfilled the inclusion and exclusion criteria took part in this study. However, one participant from conventional group did not wear the VFRs at all, while two from the FDM group could not be contacted. Two from the SLA group were no longer interested in the study and one from the SLA group had relocated. The dropouts occurred from the first follow-up and were excluded from all the analyses. Therefore, the final analysis only included eleven participants from conventional group, ten participants from FDM group, and nine participants from SLA group. Outcomes Table 2 summarizes the mean, standard deviation, and quartiles of the microbial counts and surface roughness for each group.Table 2 Descriptive statistics Microbial adherence Arch Regime Group N Mean (CFU) SD 25th 50th (Median) 75th Total microbial count Upper Full-time Conventional 11 1.150 0.936 0.180 1.110 1.550 FDM 10 12.455 16.764 0.200 1.525 25.118 SLA 9 8.170 7.986 1.550 2.110 16.170 Lower Full-time Conventional 11 14.373 16.071 0.600 5.130 33.730 FDM 10 19.754 22.446 2.713 14.270 30.053 SLA 9 13.026 5.639 8.165 14.030 17.800 Upper Part-time Conventional 11 7.457 14.674 0.260 0.440 4.820 FDM 10 5.035 5.294 2.008 2.615 7.483 SLA 9 8.846 12.079 0.735 2.340 21.635 Lower Part-time Conventional 11 10.383 17.706 0.350 2.880 15.470 FDM 10 19.034 22.023 1.520 3.130 44.135 SLA 9 13.651 24.163 1.340 1.620 28.970 Streptococcus Upper Full-time Conventional 11 4.612 11.032 0.960 1.570 1.720 FDM 10 15.448 21.207 0.773 3.430 27.930 SLA 9 13.203 17.221 0.965 3.170 27.400 Lower Full-time Conventional 11 18.475 19.665 1.970 11.470 39.270 FDM 10 19.754 22.446 2.713 14.270 30.053 SLA 9 14.712 8.989 7.020 12.070 23.065 Upper Part-time Conventional 11 11.104 17.580 0.290 0.520 15.000 FDM 10 5.035 5.294 2.008 2.615 7.483 SLA 9 8.846 8.846 8.846 8.846 8.846 Lower Part-time Conventional 11 11.720 18.296 0.260 2.890 21.870 FDM 10 19.034 19.034 19.034 19.034 19.034 SLA 9 13.651 13.651 13.651 13.651 13.651 Yeast Upper Full-time Conventional 11 0.933 1.084 0.070 0.330 2.380 FDM 10 3.052 4.176 0.050 0.180 6.250 SLA 9 0.971 1.213 0.005 0.060 2.165 Lower Full-time Conventional 11 6.288 7.789 0.170 3.470 10.530 FDM 10 6.000 6.000 6.000 6.000 6.000 SLA 9 2.432 2.432 2.432 2.432 2.432 Upper Part-time Conventional 11 1.892 2.947 0.200 0.210 4.500 FDM 10 1.902 2.131 0.780 1.230 2.405 SLA 9 1.030 1.908 0.040 0.180 1.440 Lower Part-time Conventional 11 3.394 4.544 0.130 1.330 9.730 FDM 10 6.908 9.921 1.023 1.930 10.275 SLA 9 0.583 0.583 0.583 0.583 0.583 Surface roughness Group N Mean (𝜇m) SD 25th 50th (Median) 75th Conventional 12 1.49 0.60 0.91 1.39 1.99 FDM 12 1.01 0.29 0.69 1.06 1.29 SLA 12 0.66 0.19 0.54 0.60 0.72 FDM fused deposition modeling, SLA stereolithography apparatus There were no differences in the total microbial count, Streptococcus count, and yeast count between the three groups during full-time and part-time wear on either the upper VFRs or lower VFRs (p>0.05) (Table 3). Although there was a significant difference for the yeast count of the lower VFRs during the part-time regime, post hoc analysis did not find any differences between the groups.Table 3 Comparison of the microbial adherence on vacuum-formed retainers (VFR) with different surface roughness Arch Microbes Group Full-time regime Part-time regime N Mean rank p value Effect size N Mean rank p value Effect size Value Descriptor Value Descriptor Upper Total Conventional 11 11.09 0.056 0.199 Large 11 13.00 0.465 0.042 Small FDM 10 15.75 10 17.60 SLA 9 20.61 9 16.22 Streptococcus Conventional 11 12.09 0.268 0.081 Medium 11 13.45 0.612 0.031 Small FDM 10 17.30 10 16.30 SLA 9 17.67 9 17.11 Yeast Conventional 11 15.73 0.443 0.056 Medium 11 16.00 0.241 0.110 Large FDM 10 17.80 10 18.40 SLA 9 12.67 9 11.67 Lower Total Conventional 11 13.82 0.727 0.023 Small 11 13.73 0.479 0.051 Medium FDM 10 16.40 10 18.20 SLA 9 16.56 9 14.67 Streptococcus Conventional 11 14.91 0.921 0.006 Small 11 12.55 0.287 0.086 Medium FDM 10 16.40 10 18.60 SLA 9 15.22 9 15.67 Yeast Conventional 11 17.00 0.090 0.166 Large 11 16.18 0.027$ 0.184 Large FDM 10 18.60 10 20.20 SLA 9 10.22 9 9.44 p<0.05 by Kruskal-Wallis test. $Post hoc by Dunnett T3 showed no significant differences between the groups (p>0.05). FDM fused deposition modeling, SLA stereolithography apparatus During full-time wear when all VFRs were assessed collectively, the total microbial count, Streptococcus count, and yeast count were significantly (p<0.05) more in the lower VFRs compared to the upper VFRs (Table 4). When the VFRs were assessed based on groups, only the conventional group showed a similar trend of having significantly (p<0.05) more total microbial count, Streptococcus count, and yeast count in the lower VFRs compared to the upper retainers. During part-time wear when all VFRs were assessed collectively, the total microbial count, Streptococcus count, and yeast count were also significantly (p<0.05) more in the lower VFRs compared to the upper retainers. However, when the VFRs were assessed based on groups, the difference in microbial colony counts between the upper and lower VFRs was not significant (p>0.05).Table 4 Comparison of the microbial adherence on vacuum-formed retainers (VFR) of different arches (upper vs lower) Regime Group Overall Conventional FDM SLA N Mean rank p value Effect size (descriptor) N Mean rank p value Effect size (Descriptor) N Mean rank p value Effect size (descriptor) N Mean rank p value Effect size (descriptor) Full-time (upper vs lower) Total -ve Ranks 8a 12.00 0.005 0.513 (Large) 2a 1.50 0.008* 0.805 (Large) 2a 7.50 0.201 0.404 (Medium) 4a 3.50 0.313 0.337 (Medium) +ve Ranks 22b 16.77 9b 7.00 8b 5.00 5b 6.20 Ties 0c 0c 0c 0c Total 30 11 10 9 Strep. -ve Ranks 9d 13.22 0.019* 0.427 (Medium) 1d 1.00 0.004* 0.856 (Large) 4d 4.50 0.331 0.307 (Medium) 4d 4.00 0.440 0.258 (Medium) +ve Ranks 21e 16.48 10e 6.50 6e 6.17 5e 5.80 Ties 0f 0f 0f 0f Total 30 11 10 9 Yeast -ve Ranks 6g 11.50 0.004* 0.527 (Large) 2g 1.50 0.012* 0.754 (Large) 2g 7.50 0.201 0.404 (Medium) 2g 4.50 0.395 0.283 (Medium) +ve Ranks 21h 14.71 8h 6.50 8h 5.00 5h 3.80 Ties 3i 1i 0i 2i Total 30 11 10 9 Part-time (upper vs lower) Total -ve Ranks 9a 12.78 0.016* 0.441 (Medium) 4a 3.50 0.091 0.510 (Large) 2a 5.50 0.092 0.534 (Large) 3a 4.67 0.313 0.337 (Medium) +ve Ranks 21b 16.67 7b 7.43 8b 5.50 6b 5.17 Ties 0c 0c 0c 0c Total 30 11 10 9 Strep. -ve Ranks 10d 12.20 0.023* 0.415 (Medium) 5d 4.40 0.327 0.295 (Medium) 2d 5.50 0.092 0.534 (Large) 3d 4.00 0.212 0.416 (Medium) +ve Ranks 20e 17.15 6e 7.33 8e 5.50 6e 5.50 Ties 0f 0f 0f 0f Total 30 11 10 9 Yeast -ve Ranks 13g 11.77 0.163* 0.245 (Small) 4g 2.50 0.074 0.483 (Large) 4g 3.50 0.167 0.437 (Medium) 5g 6.20 0.312 0.337 (Medium) +ve Ranks 16h 17.63 6h 7.50 6h 6.83 4h 3.50 Ties 1i 1i 0i 0i Total 30 11 10 9 aTotal microbial on lower VFR < Total microbial on upper VFR bTotal microbial on lower VFR > Total microbial on upper VFR cTotal microbial on lower VFR = Total microbial on upper VFR dStreptococcus on lower VFR < Streptococcus on upper VFR eStreptococcus on lower VFR > Streptococcus on upper VFR fStreptococcus on lower VFR = Streptococcus on upper VFR gYeast on lower VFR < Yeast on upper VFR hYeast on lower VFR > Yeast on upper VFR iYeast on lower VFR = Yeast on lower VFR p < 0.05 by Wilcoxon signed-rank test; FDM, fused deposition modeling; SLA, stereolithography apparatus. When assessing the upper VFRs alone, there were no differences in the total microbial count, Streptococcus count, and yeast count between full-time and part-time wear, as assessed collectively or by each group (Table 5). Similarly, when assessing the lower VFRs alone, there were no differences in the total microbial count, Streptococcus count, and yeast count between full-time and part-time wear (p>0.05).Table 5 Comparison of the microbial adherence on vacuum-formed retainers (VFR) of different retention regimes (full-time vs part-time) Arch Group Overall Conventional FDM SLA N Mean rank p value Effect size (Descriptor) N Mean rank p value Effect size (Descriptor) N Mean Rank p-value Effect Size (Descriptor) N Mean rank p value Effect size (Descriptor) Upper (full-time vs part-time) Total -ve Ranks 14a 14.36 0.964 0.008 (Small) 6a 4.50 0.593 0.161 (Small) 4a 6.50 0.261 0.356 (Medium) 4a 6.00 0.859 0.059 (Small) +ve Ranks 14b 14.64 5b 7.80 4b 2.50 5b 4.20 Ties 2c 0c 2c 0c Total 30 11 10 9 Strep. -ve Ranks 14d 14.43 0.982 0.004 (Small) 6d 4.00 0.423 0.241 (Small) 6d 4.17 0.325 0.312 (Medium) 2d 8.50 0.513 0.218 (Small) +ve Ranks 14e 14.57 5e 8.40 2e 5.50 7e 4.00 Ties 2f 0f 2f 0f Total 30 11 10 9 Yeast -ve Ranks 12g 15.46 0.799 0.029 (Small) 4g 6.38 0.504 0.188 (Small) 4g 5.50 0.574 0.178 (Small) 4g 4.50 0.497 0.139 (Small) +ve Ranks 14h 11.82 7h 5.79 4h 3.50 3h 3.33 Ties 4i 0i 2i 2i Total 30 11 10 9 Lower (full-time vs part-time) Total -ve Ranks 18a 13.22 0.425 0.146 (Small) 7a 6.57 0.247 0.349 (Medium) 4a 4.50 1.000 0.000 (Small) 7a 4.00 0.514 0.218 (Small) +ve Ranks 10b 16.80 4b 5.00 4b 4.50 2b 8.50 Ties 2c 0c 2c 0c Total 30 11 10 9 Strep. -ve Ranks 21d 12.33 0.202 0.233 (Small) 10d 6.40 0.006 0.832 (Large) 4d 4.50 1.000 0.000 (Small) 7d 4.00 0.513 0.218 (Small) +ve Ranks 7e 21.00 1e 2.00 4e 4.50 2e 8.50 Ties 2f 0f 2f 0f Total 30 11 10 9 Yeast -ve Ranks 11g 16.55 0.632 0.087 (Small) 5g 7.60 0.656 0.134 (Small) 2g 5.50 0.325 0.312 (Medium) 4g 5.00 0.766 0.099 (Small) +ve Ranks 17h 13.18 6h 4.67 6h 4.17 5h 5.00 Ties 2i 0i 2i 0i Total 30 11 10 9 aTotal microbial during PT < Total microbial during FT bTotal microbial during PT < > Total microbial during FT cTotal microbial during PT < = Total microbial during FT dStreptococcus during PT < < Streptococcus during FT eStreptococcus during PT < > Streptococcus during FT fStreptococcus during PT < = Streptococcus during FT gYeast during PT < < Yeast on during FT hYeast during PT < > Yeast on during FT iYeast during PT < = Yeast on during FT p < 0.05 by Wilcoxon signed-rank test; FDM, fused deposition modeling; SLA, stereolithography apparatus. The mean surface roughness of the conventional models, FDM models, and SLA models were 1.49 μm (S.D. 0.60), 1.01 μm (S.D. 0.29), and 0.66 μm (S.D. 0.19), respectively, which were significantly different (p<0.05) (Table 6). Post hoc pairwise comparison showed that the surface roughness was significantly lower in SLA compared to the conventional and FDM working models (p<0.05) but not between the conventional and FDM models (p>0.05).Table 6 Surface roughness of the working models Group Kruskal-Wallis test Post hoc pairwise comparison N Mean rank p value Effect size Comparisons Test statistics Adjusted p value Effect size Value Descriptor Value Descriptor Conventional 12 28.83 SLA vs FDM 10.667 0.039 0.305 Large FDM 12 19.67 0.000* 0.497 Large SLA vs Conventional 17.833 0.000* 0.510 Large SLA 12 9.00 FDM vs Conventional 7.167 0.287 0.205 Large *p<0.05; FDM, fused deposition modeling; SLA, stereolithography apparatus. In terms of the association between surface roughness and microbial count, there was no correlation between the working model surface roughness and total microbial count of both upper and lower VFRs collectively regardless of retention regime (N=30; τb = −0.037, p = 0.775). There were no correlations between the surface roughness and total microbial count of both upper and lower VFRs collectively either during full-time wear (N=30; τb = −0.080, p = 0.543) or part-time wear (N=30; τb = −0.073, p = 0.579). Harms No harms were observed. No side effects or adverse events were reported by the participants. Discussion Interpretation The current study showed that surface roughness of the working models varies according to the type of working models used, and the imprints can be observed on the VFRs. VFRs harbor oral microbes; the amount of colonization did not differ between VFRs with different surface roughness and between full-time and part-time use. However, lower VFRs tend to accumulate more oral microbes, potentially increasing the oral health risk in the lower arch compared to the upper arch. Inner surfaces of the thermoplastic appliance are not completely smooth and have micro abrasions and irregularities, which may promote bacterial adhesion [15]. The surface roughness threshold that facilitates biofilm formation is estimated to be at least 0.2 mm [26]. Given that the surface roughness of the VFRs in the current study was indirectly measured to be above this threshold, the rough surfaces had encouraged microbial adherence in all groups. Nonetheless, the microbial adherence on VFRs in this study was not significantly different between VFRs with variable surface roughness as constructed on different types of working models. This concurred with an in vitro study that compared commercially available VFR materials with variable surface roughness, which found initial bacterial adhesion increased with time but were not statistically different between the VFRs [27]. The lack of association between surface roughness and microbial adhesion as found in this study suggests that surface roughness may not be the predominant factor for microbial adherence on VFRs. Other surface characteristics such as surface attraction to water and surface free energy also contribute to various biochemical interactions that influence the initial adhesion of microorganisms to surfaces [28]. Thermoplastic VFRs have smoother and more hydrophilic surfaces, higher electron donor properties, and acid-base interactions compared to auto-polymerized acrylic resins, commonly used for Hawley retainers. Thus, thermoplastic retainers tended to have a more uniformly distributed pattern of bacterial attachment, while bacteria tended to aggregate on the rough surfaces of auto-polymerized acrylic resins [28]. The electron donor/electron acceptor interactions of the acid-base element of surface free energy may have favored for the strong initial adhesion and uniform distribution between oral bacteria and the thermoplastic material, over surface roughness. Streptococci that are equipped with external appendages such as fimbriae exhibit cell-surface hydrophobicity contributed by the cell-surface molecules consisting of non-polar amino acids. This hydrophobic surface property, which is also possessed by oral candida, has been reported to be involved in the formation of hydrophobic bonds between streptococci and the oral surface during the early colonizing stage [29, 30]. When all VFRs were considered regardless of group, the current study found significantly more oral microbes in the lower VFRs than the upper VFRs during full-time wear. Further analysis by group, only the conventional group showed the same findings, where the total microbial count, Streptococcus count, and yeast count were higher on the lower VFRs during full-time wear. Overall, during part-time wear, the total microbial count and Streptococcus count were higher in the lower VFRs compared to the upper VFRs. This may appear unusual as the salivary flow on the lower arch is expected to be good for self-cleansing [31]. However, it is possible that the design of the VFRs that covers the whole dentition may have inhibited the self-cleansing property and thus caused an increase in microbial load. Saliva is comprised of a variety of electrolytes that includes sodium, potassium, calcium, magnesium, bicarbonate, and phosphates. Other components that can be found in saliva are salivary proteins such as immunoglobulins, proteins, enzymes, mucins, and nitrogenous products such as urea and ammonia. Salivary proteins and mucins serve to cleanse, aggregate, and/or attach oral microorganisms and contribute to dental plaque metabolism [32]. As amphifunctional macromolecules, salivary proteins may act for as well as against the host [33], that is, they may have more than one function and perform similar functions. Prolonged exposure during full-time wear of the lower VFRs with saliva may have increased microbial adherence through self-multiplication of the microbes and co-adhesion of those carried over by the oral fluid. Hence, saliva that usually pools on the lower arch could also have supported the microbial growth. In terms of duration of wear, the current study generally found no differences in microbial adherence on VFRs of variable surface roughness between full-time wear and part-time wear. However, on the lower VFRs of the conventional group, only the Streptococcus count was found to be higher during full-time wear compared with part-time wear. Streptococcus that adheres to a surface via hydrophobic interactions of the fimbriae and adhesin receptor interactions between the bacteria and salivary components on the surface form strong irreversible attachment that enables further co-adhesion of microbes, leading to the higher population observed [34], but in yeast attachment is determined by certain cell wall components [35]. VFRs that were fabricated on conventional models may have increased surface roughness as shown in our result, which may have promoted adherence of streptococci. The finding of this study suggests that VFRs left in the containers during part-time wear may harbor oral microbes as much as the oral microbes that are present in the oral cavity as used during full-time wear. The instructions on VFR care given to participants were to clean the retainers using toothbrush and to keep the retainers in a covered container when not in use [36]. The retainers were also kept in water, which may have harbored bacterial growth. Further research should investigate the effect of storage conditions on bacterial growth on VFRs. The result of surface roughness measurement was statistically significant for the different types of working models used. SLA model was the smoothest, followed by FDM model, and the roughest was conventional model. The dental stone were mixed manually according to the water/powder ratio suggested by the manufacturer. Therefore, the smoothness of the mixture can vary between different technicians and may affect the consistency of the surface characteristic of the model produced. On the other hand, the FDM printed models are made of continuous filaments of thermoplastic polymers or fiber-reinforced polymers, while SLA printed models are produced using resin with photoactive monomers or hybrid polymer-ceramic [37]. The FDM and SLA models are printed using their respective 3D printers with the same setting and printing parameters all the time. Therefore, the final outcome of these 3D printed models can be predicted to be reliable and not affected by operator inconsistency. In our study, the printing quality for SLA models was demonstrated to be better compared to FDM models. This finding is similar to other studies conducted where they also found that SLA has the highest quality of print while FDM had the poorest print quality [38–40]. Limitations Measurement of the surface roughness was based on few assumptions. First, the VFR being a transparent material could not be directly measured by the surface texture analyzer. Since surface roughness of the VFRs had to be indirectly measured on their corresponding working models, it had to be assumed that the VFRs negatively copied all the imprints of the working models, and the imprints of the working models represented the negative imprints of the VFRs. Second, the labial surface of the incisors was chosen for measuring surface roughness because it was assumed that the VFR foils adapt closest on the smooth surface where the imprints of the 3D printing layers had the most clarity. VFR does not wrap well over undercut areas and curved surfaces such as the cervical margins and occlusal fossae. Thus, the imprints may not be as well-defined in these areas. Third, mechanical cleansing of VFR by toothbrushing may possibly affect the surface roughness [41]. Thus, it had to be assumed that the increase in surface roughness by the participants was similar between groups. Compliance was based on patients’ report, which is associated with recall bias, particularly if the data was recorded retrospectively during the follow-up visits [42], or over-reporting to please the attending clinician and to avoid negative comments or judgments [43]. The compliance of the study was considered good, contributed by the weekly reminder by the researcher. Participants were shown models of relapse cases to improve compliance [44] from when the first interventional retainers were issued to emphasize the importance of retainers to prevent relapse. The dropout rate of 17% in the current study was slightly higher than the attrition of 10% shown in a past study [10]. There are few factors that could have contributed to this. First, the most concerning factor is unreported problems with the retainers, particularly with VFR-FDM which had the highest dropout, followed by VFR-CV and VFR-SLA. This may contribute to a bias result. Second, it was a challenge to perform a clinical trial during the coronavirus disease 2019 (COVID-19) pandemic. Our trial commenced in December 2019, and our government had enforced movement control order in various phases from 18 March 2020, which had restricted movements throughout Malaysia as an effort to control the outbreak [45]. Although patients were allowed to attend for their dental appointments, there were many uncertainties in terms of mobility for the public, which possibly had contributed to a higher attrition in this study. Nonetheless, the study had an adequate sample with the minimum of nine participants per group. The oral hygiene aids used were daily use of toothpaste using a toothbrush, which is commonly practiced by 99% of Malaysians [46]. Other oral hygiene aid such as mouthwash can be an effective method to control cariogenic plaque formation [47]. However, the use of mouthwash is still not a common practice among Malaysians. Mitha et al. [48] reported only about 34.8% respondents use mouthwash daily, while the remaining respondents use mouthwash less frequently. Therefore, the study limited the oral hygiene aid that was a common practice, which was daily use of toothpaste using a toothbrush, to prevent confounders of poor compliance with other oral hygiene aid such as mouthwash. The study did not use appliance cleansers since the focus was to measure the amount of bacterial adherence on retainers during use. The study demonstrated bacterial adherence on all three types of VFR used. Thus, toothbrushing alone is not sufficient to clean the retainer. It can be recommended to use appliance cleanser for improved appliance hygiene. Various types of appliances cleansers have shown different efficacy in cleaning the retainer material [49]. Generalizability The results of the study can be applied to healthy young adults from both genders who had completed fixed appliances treatment with no history of smoking and systemic diseases. By stratifying for gender, we have controlled for any confounder of having more females who may have better oral hygiene than males when comparing between groups. Furthermore, microbial samples were collected at 3 months, which coincided with standard protocol for retainer review, yet would be long enough to detect change in microbial establishment [12]. The study can be applied for VFRs made on working models with surface roughness of at most 1.49 mm (SD 0.60). Mohd Tahir et al. [10] used an FDM printer which had a layer resolution of 150 mm. However, technology has become more current such that FDM printers which are considered one of the cheapest commercially available printers are able to print at higher resolution as thin as 60 mm for FDM, while the SLA model was printed at 25 mm. One of the advantages of the 3D printed models noted from this study was that the same replica can be used to repeat VFR constructions, while new casts of the conventional models had to be used for constructing the second VFR set. This is because 3D printed acrylic resin has better mechanical properties in terms of higher impact strength, hardness, compressive strength, and flexural strength in comparison with the dental stone models [50]. This can potentially be the cost-effective benefit when patients request for replacement retainers provided that there was no relapse. Conclusions The propensity for microbial adherence on VFRs was not influenced by the degree of surface roughness imprints from working models, as made from conventional and 3D printed models. Clinicians can consider using either conventional, FDM or SLA models to make VFRs since the risk for microbial accumulation was comparable. Lower VFRs have a higher propensity for microbial adherence than upper VFRs, thus potentially increasing the oral health risk in the lower arch. There was no difference in microbial adherence on VFRs between full-time and part-time wear; hence, the risk to the oral health was similar whether patients wore the VFRs full-time or part-time. Acknowledgements The authors would like to thank Mohd Anuar Zainon for microbial count calibration and Mohammad Zabri Johari for statistical advice. Author contributions SB was responsible for the conceptualization, data curation, formal analysis, funding acquisition, investigation, methodology, project administration, and writing of the original draft. WNWH was responsible for the conceptualization, funding acquisition, methodology, project administration, resources, supervision, validation, visualization, and reviewing and editing the draft. FAR was responsible for the conceptualization, methodology, project administration, resources, supervision, visualization, and reviewing and editing the draft. NMT was responsible for the methodology, validation, formal analysis, and reviewing and editing the draft. Funding The research was funded by the Universiti Malaya Dental Postgraduate Research Grant (DPRG/14/19). Data availability Data of the study is available from the corresponding author upon reasonable request. Declarations Ethics approval This study was performed in line with the principles of the Declaration of Helsinki. Ethics approval was obtained from the Medical Ethics Research Committee, Faculty of Dentistry, Universiti Malaya [Ref: DF CD1811/0047(P); July 12, 2018]. The research was registered with ClinicalTrials.gov (Ref: NCT03844425). Consent to participate Informed consent was obtained from all individual participants included in the study. Conflict of interest The authors declare no competing interests. Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Traore O Springthorpe V Sattar S A quantitative study of the survival of two species of Candida on porous and non-porous environmental surfaces and hands J Appl Microbiol 2002 92 549 555 10.1046/j.1365-2672.2002.01560.x 11872132 2. Eliades T Eliades G Brantley WA Microbial attachment on orthodontic appliances: I. Wettability and early pellicle formation on bracket materials Am J Orthod Dentofacial Orthop 1995 108 351 360 10.1016/s0889-5406(95)70032-3 7572846 3. Marsh P Martin M Oral microbiology 2009 Edinburgh/New York Elsevier 4. Samaranayake LP Essential microbiology for dentistry 2018 Edinburgh Churchill Livingstone Elsevier 5. Uygun-Can B Kadir T Akyüz S Oral candidal carriage in children with and without dental caries Quintessence Int 2007 38 45 49 17216907 6. Urzúa B Hermosilla G Gamonal J Morales-Bozo I Canals M Barahona S Yeast diversity in the oral microbiota of subjects with periodontitis: Candida albicans and Candida dubliniensis colonize the periodontal pockets Sabouraudia 2008 46 783 793 10.1080/13693780802060899 7. Sheridan JJ LeDoux W McMinn R Essix retainers: fabrication and supervision for permanent retention J Clin Orthod 1993 27 37 45 8478438 8. Saleh M Hajeer MY Muessig D Acceptability comparison between Hawley retainers and vacuum-formed retainers in orthodontic adult patients: a single-centre, randomized controlled trial Eur J Orthod 2017 39 453 461 10.1093/ejo/cjx024 28430890 9. Jaber ST Hajeer MY Khattab TZ Mahaini L Evaluation of the fused deposition modeling and the digital light processing techniques in terms of dimensional accuracy of printing dental models used for the fabrication of clear aligners Clin Exp Dent Res 2021 7 591 600 10.1002/cre2.366 33258297 10. Mohd Tahir N Wan Hassan WN Saub R Comparing retainers constructed on conventional stone models and on 3D printed models: a randomized crossover clinical study Eur J Orthod 2019 41 370 380 10.1093/ejo/cjy063 30321319 11. Eroglu AK Baka ZM Arslan U Comparative evaluation of salivary microbial levels and periodontal status of patients wearing fixed and removable orthodontic retainers Am J Orthod Dentofacial Orthop 2019 156 186 192 10.1016/j.ajodo.2018.08.022 31375228 12. Türköz Ç Bavbek NC Varlik SK Akça G Influence of thermoplastic retainers on Streptococcus mutans and Lactobacillus adhesion Am J Orthod Dentofacial Orthop 2012 141 598 603 10.1016/j.ajodo.2011.11.021 22554754 13. Cheng R Yang H Shao MY Hu T Zhou XD Dental erosion and severe tooth decay related to soft drinks: a case report and literature review J Zhejiang Univ Sci B 2009 10 395 399 10.1631/jzus.B0820245 19434767 14. Cifter M Gumru Celikel AD Cekici A Effects of vacuum-formed retainers on periodontal status and their retention efficiency Am J Orthod Dentofacial Orthop 2017 152 830 835 10.1016/j.ajodo.2017.05.029 29173862 15. Low B Lee W Seneviratne CJ Samaranayake LP Hagg U Ultrastructure and morphology of biofilms on thermoplastic orthodontic appliances in ‘fast’ and ‘slow’ plaque formers Eur J Orthod 2011 33 577 583 10.1093/ejo/cjq126 21187528 16. Outhaisavanh S Liu Y Song J The origin and evolution of the Hawley retainer for the effectiveness to maintain tooth position after fixed orthodontic treatment compare to vacuum-formed retainer: a systematic review of RCTs Int Orthod 2020 18 225 236 10.1016/j.ortho.2020.02.008 32201168 17. Wan Hassan WN Othman SA Chan CS Ahmad R Ali SN Abd Rohim A Assessing agreement in measurements of orthodontic study models: digital caliper on plaster models vs 3-dimensional software on models scanned by structured-light scanner Am J Orthod Dentofacial Orthop 2016 150 886 895 10.1016/j.ajodo.2016.04.021 27871715 18. Malhotra N Rao SP Acharya S Vasudev B Comparative in vitro evaluation of efficacy of mouthrinses against Streptococcus mutans, Lactobacilli and Candida albicans Oral Health Prev Dent 2011 9 261 268 22068182 19. Ghazal ARA Idris G Hajeer MY Alawer K Cannon RD Efficacy of removing Candida albicans from orthodontic acrylic bases: an in vitro study BMC Oral Health 2019 19 71 10.1186/s12903-019-0765-x 31046747 20. Smith JR Laudicina RJ Rufo RD Teacher’s manual to accompany learning guides for the medical microbiology laboratory 1985 Wiley 21. Koo TK Li MY A guideline of selecting and reporting intraclass correlation coefficients for reliability research J Chiropr Med 2016 15 155 163 10.1016/j.jcm.2016.02.012 27330520 22. Farhadian N Usefi Mashoof R Khanizadeh S Ghaderi E Farhadian M Miresmaeili A Streptococcus mutans counts in patients wearing removable retainers with silver nanoparticles vs those wearing conventional retainers: a randomized clinical trial Am J Orthod Dentofacial Orthop 2016 149 155 160 10.1016/j.ajodo.2015.07.031 26827971 23. Mamai-Homata E Koletsi-Kounari H Margaritis V Gender differences in oral health status and behavior of Greek dental students: a meta-analysis of 1981, 2000, and 2010 data J Int Soc Prev Community Dent 2016 6 60 10.4103/2231-0762.175411 27011935 24. Chinna K Yuen C Statistical analysis using SPSS 2016 Kuala Lumpur Pearson 25. Allen P Bennett K Heritage B SPSS statistics version 22: A practical guide 2014 Australia Cengage Learning 26. Teughels W Van Assche N Sliepen I Quirynen M Effect of material characteristics and/or surface topography on biofilm development Clin Oral Implants Res 2006 17 Suppl 2 68 81 10.1111/j.1600-0501.2006.01353.x 16968383 27. Tektas S Thurnheer T Eliades T Attin T Karygianni L Initial bacterial adhesion and biofilm formation on aligner materials Antibiotics (Basel) 2020 9 908 10.3390/antibiotics9120908 33333723 28. Al Groosh DH Bozec L Pratten J Hunt NP The influence of surface roughness and surface dynamics on the attachment of methicillin-resistant Staphylococcus aureus onto orthodontic retainer materials Dent Mater J 2015 34 585 594 10.4012/dmj.2014-045 26438981 29. Razak FA Othman RY Abd Rahim ZH The effect of Piper betle and Psidium guajava extracts on the cell-surface hydrophobicity of selected early settlers of dental plaque J Oral Sci 2006 48 71 75 10.2334/josnusd.48.71 16858135 30. Harun WHAW Razak FA An in vitro study on the anti-adherence effect of Brucea javanica and Piper betle extracts towards oral Candida Arch Oral Biol 2013 58 1335 1342 10.1016/j.archoralbio.2013.07.001 23915676 31. Dawes C Watanabe S Biglow-Lecomte P Dibdin G Estimation of the velocity of the salivary film at some different locations in the mouth J Dent Res 1989 68 1479 1482 10.1177/00220345890680110201 2531176 32. Humphrey SP Williamson RT A review of saliva: normal composition, flow, and function J Prosthet Dent 2001 85 162 169 10.1067/mpr.2001.113778 11208206 33. Edgerton M Scannapieco F Reddy M Levine M Human submandibular-sublingual saliva promotes adhesion of Candida albicans to polymethylmethacrylate Infect Immun 1993 61 2644 2652 10.1128/iai.61.6.2644-2652.1993 8500903 34. Abranches J Zeng L Kajfasz JK Palmer SR Chakraborty B Wen ZT Richards VP Brady LJ Lemos JA Biology of oral streptococci Microbiol Spectr 2018 6 6 11 10.1128/microbiolspec.GPP3-0042-2018 35. Singh A, Verma R, Murari A, Agrawal A (2014) Oral candidiasis: an overview. J Oral Maxillofac Pathol 18:S81-S85 10.4103/0973-029X.141325 36. Meade MJ Millett D Retention protocols and use of vacuum-formed retainers among specialist orthodontists J Orthod 2013 40 318 325 10.1179/1465313313Y.0000000066 24297964 37. Ngo TD Kashani A Imbalzano G Nguyen KT Hui D Additive manufacturing (3D printing): a review of materials, methods, applications and challenges Compos B Eng 2018 143 172 196 10.1016/j.compositesb.2018.02.012 38. Kasparova M Grafova L Dvorak P Dostalova T Prochazka A Eliasova H Possibility of reconstruction of dental plaster cast from 3D digital study models Biomed Eng Online 2013 12 1 11 10.1186/1475-925X-12-49 23289769 39. Finnes T High definition 3D printing–comparing SLA and FDM printing technologies J Undergrad Res 2015 13 3 40. Choudhari C Patil V Product development and its comparative analysis by SLA, SLS and FDM rapid prototyping processes IOP Conf Ser: Mater Sci Eng 2016 149 012009 10.1088/1757-899X/149/1/012009 41. Šimunović L Blagec T Meštrović S The influence of different cleaning protocols on the surface roughness of orthodontic retainers Appl Sci 2023 13 1319 10.3390/app13031319 42. Schott TC Meyer-Gutknecht H Mayer N Weber J Weimer K A comparison between indirect and objective wear-time assessment of removable orthodontic appliances Eur J Orthod 2017 39 170 175 10.1093/ejo/cjw026 27030283 43. Al-Moghrabi D Salazar FC Pandis N Fleming PS Compliance with removable orthodontic appliances and adjuncts: a systematic review and meta-analysis Am J Orthod Dentofacial Orthop 2017 152 17 32 10.1016/j.ajodo.2017.03.019 28651764 44. Lin F Sun H Ni Z Zheng M Yao L A feasible method to improve adherence of Hawley retainer in adolescent orthodontic patients: a randomized controlled trial Patient Prefer 2015 9 1525 1530 10.2147/PPA.S94111 45. Hussin MZ Farook MS Nor NAM Hariri F Kadir K Zakaria NN Hassan MK Wan Hassan WN Resuming clinical teaching in the era of COVID-19: experiences and protocols from a dental school in Malaysia Sains Malays 2021 50 2123 2134 10.17576/jsm-2021-5007-25 46. Mitha S ElNaem MH Chandran J Rajah NP Fam TY Babar MG Siddiqui MJ Jamshed S Use of oral cleaning devices and their perceived benefits among Malaysians in Kuala Lumpur and Johor Bahru: an exploratory structured approach J Pharm Bioallied Sci 2018 10 216 225 10.4103/JPBS.JPBS_296_16 30568379 47. Pithon MM Sant'Anna LI Baião FC dos Santos RL RdaS C Maia LC Assessment of the effectiveness of mouthwashes in reducing cariogenic biofilm in orthodontic patients: a systematic review J Dent 2015 43 297 308 10.1016/j.jdent.2014.12.010 25572792 48. Mitha S Elnaem MH Koh M En C Babar MG Siddiqui J Jamshed S Use and perceived benefits of mouthwash among Malaysian adults: an exploratory insight J Adv Oral Res 2016 7 7 14 10.1177/2229411220160302 49. Kiatwarawut K Kuvatanasuchati J Thaweboon B Sirisoontorn I Comparison of various antimicrobial agents for thermoplastic polymeric retainers Polymers 2022 14 3753 10.3390/polym14183753 36145897 50. Czajkowska M, Walejewska E, Zadrozny L, Wieczorek M, Swieszkowski W, Wagner L, Mijiritsky E, Markowski J (2020) Comparison of dental stone models and their 3d printed acrylic replicas for the accuracy and mechanical properties. Materials (Basel) 13. 10.3390/ma13184066
PMC010xxxxxx/PMC10034885.txt	==== Front Multibody Syst Dyn Multibody Syst Dyn Multibody System Dynamics 1384-5640 1573-272X Springer Netherlands Dordrecht 9894 10.1007/s11044-023-09894-9 Editorial Preface Kövecses József [email protected] 1 Stépán Gábor 2 Ambrósio Jorge 3 1 grid.14709.3b 0000 0004 1936 8649 McGill University, Montreal, Quebec Canada 2 grid.6759.d 0000 0001 2180 0451 Budapest University of Technology and Economics, Budapest, Hungary 3 grid.9983.b 0000 0001 2181 4263 IDMEC, Instituto Superior Técnico, Technical University of Lisbon, Lisbon, Portugal 23 3 2023 12 15 2 2023 © The Author(s), under exclusive licence to Springer Nature B.V. 2023 This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. ==== Body pmcMultibody System Dynamics is a rapidly growing and developing field of Mechanics. It has been experiencing significant increase in a variety of applications in the development of complex state of the art systems. Multibody system dynamics in general addresses computational mechanics, solid mechanics, nonlinear dynamics and control. Major developments have been taking place in several thematic areas such as Theoretical modelling, formalisms and computational methods; Flexible multibody systems; Contact and impact problems; Mechatronics, robotics and control; Multidisciplinary approaches; Efficient computational methods and real-time applications; Experiments and numerical verifications; Optimization, sensitivity analysis and parameter identification; Dynamics of machines; Vehicle dynamics and aerospace applications; Biomechanics; and various other topics. The Eccomas Thematic Conference on Multibody Dynamics is a biannual conference series; it was established in 2003 with its inaugural edition in Lisbon, Portugal. The following editions of the series took place in Madrid (2005), Milan (2007), Warsaw (2009), Brussels (2011), Zagreb (2013), Barcelona (2015), Prague (2017), Duisburg (2019), and Budapest (2021 online). The conference series serves as a prime opportunity for researchers and professionals worldwide to exchange ideas in multibody dynamics concerning theoretical aspects, computational approaches, and in applied research such as vehicle dynamics, robotics, mechatronics, and biomechanics. The conference provides an excellent platform for sharing novel ideas within the continuously growing multibody community. This is, therefore, a privileged ground for the dissemination of new developments in multibody dynamics. This thematic issue is dedicated to the 10th Eccomas Thematic Conference on Multibody Dynamics. The conference took place December 12–15, 2021 online. The conference was originally scheduled to take place as a regular in-person event in Budapest, Hungary. However, the circumstances of the Covid-19 pandemic forced it to be an online event. The conference covered all areas of multibody dynamics and included 145 contributed presentations from 27 countries. We were invited to organize a Thematic Issue of Multibody System Dynamics from the excellent, mature contributions presented at the conference to reflect the new developments in the different areas that contribute to Multibody Dynamics. We invited authors to submit full manuscripts to the journal describing the novel contributions representative of the advances in the field. These manuscripts underwent the rigorous peer review process that is a hallmark of this journal. Among the manuscripts accepted, we selected 10 contributions for inclusion in the thematic issue. These give a representative cross section of the novel developments in the topics presented at the conference. Several other papers submitted to the thematic issue, and accepted after peer-reviewing, are being published in regular issues of the journal. We hope you enjoy reading all papers that resulted from the excellent research contributions presented at 10th Eccomas Thematic Conference on Multibody Dynamics. Declarations Competing Interests The authors declare no competing interests. This article appeared in the wrong Issue. The preface is part of the Special Issue on 10th ECCOMAS Multibody Dynamics (Volume 57 Issue 3-4) that was published in April 2023. Accidentally, it was not included in the correct Issue. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
PMC010xxxxxx/PMC10036307.txt	==== Front Clin Ther Clin Ther Clinical Therapeutics 0149-2918 1879-114X Merck Sharp & Dohme LLC., a subsidiary Merck & Co., Inc., Rahway, NJ, USA and The Author(s). Published by Elsevier Inc. S0149-2918(23)00109-1 10.1016/j.clinthera.2023.03.012 Original Research Prevalence of Potential Drug-drug Interactions With Ritonavir-containing COVID-19 Therapy in the United States: An Analysis of the National Health and Nutrition Examination Survey Igho-Osagie Ebuwa DrPH, MBA, MBBS 1 Brzozowski Kaylen MPH 2⁎ Jin Harry PhD, MPH 2 Brown Jeffrey PhD 2 Williams Marissa Grifasi PharmD 1 Puenpatom Amy PhD 1 1 Merck & Co Inc, Rahway, New Jersey 2 TriNetX, Cambridge, Massachusetts ⁎ Address correspondence to: Kaylen Brzozowski, TriNetX, 125 Cambridgepark Dr, Ste 500, Cambridge, MA 02140. 24 3 2023 5 2023 24 3 2023 45 5 390399.e4 13 3 2023 © 2023 Merck Sharp & Dohme LLC., a subsidiary Merck & Co., Inc., Rahway, NJ, USA and The Author(s). Published by Elsevier Inc. 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Purpose The evolving epidemiology and treatment landscape of COVID-19 necessitates research into potential drug-drug interactions (pDDIs) from the use of new treatments for COVID-19, particularly those that contain ritonavir, a potent inhibitor of the cytochrome P350 3A4 (CYP3A4) metabolic pathway. In this study, we assessed the prevalence of pDDIs between medications for chronic conditions metabolized through the CYP3A4 metabolic pathway and ritonavir-containing COVID-19 medications in the US general population. Methods This study combined National Health and Nutrition Examination Survey (NHANES) waves 2015 to 2016 and 2017 to March 2020 to observe pDDI prevalence between ritonavir-containing therapy and coadministered medications among US adults 18 years or older. CYP3A4-mediated medications were identified from affirmative medication questionnaire response and associated prescription examination by surveyors. CYP3A4-mediated medications with associated pDDIs with ritonavir and assessed pDDI severity (minor, major, moderate, and severe) were obtained from the University of Liverpool's COVID-19 online drug interaction checker, Lexicomp, and US Food and Drug Administration fact sheets. pDDI prevalence and severity were evaluated by demographic characteristics and COVID-19 risk factors. Findings A total of 15,685 adult participants were identified during the 2015 to 2020 NHANES waves. Survey participants used a mean (SD) of 2.7 (1.8) drugs with likelihood of a pDDI. The weighted prevalence of major to contraindicated pDDIs among the US population was 29.3%. Prevalence rates among those 60 years and older, with serious heart conditions, with moderate chronic kidney disease (CKD), with severe CKD, with diabetes, and with HIV were 60.2%, 80.7%, 73.9%, 69.5%, 63.4%, and 68.5%, respectively. Results remained largely unchanged after removal of statins from the list of drugs associated with ritonavir-based pDDIs. Implications Approximately one-third of the US population would be at risk for a major or contraindicated pDDI should they receive a ritonavir-containing regimen, and this risk increases significantly among individuals 60 years or older and with comorbidities such as serious heart conditions, CKD, diabetes, and HIV. The state of polypharmacy in the US population and the quickly changing COVID-19 landscape indicate significant risk of pDDIs among those requiring treatment with ritonavir-containing COVID-19 medications. Practitioners should take polypharmacy, age, and comorbidity profile into account when prescribing COVID-19 therapies. Alternative treatment regimens should be considered, especially for those of older age and those with risk factors for progression to severe COVID-19. Key Words COVID-19 drug interaction NHANES nirmatrelvir/ritonavir polypharmacy ritonavir Abbreviations pDDI Potential drug-drug interaction ==== Body pmcEighty-eight million cases of COVID-19 and >1 million COVID-19–related deaths have occurred in the United States since January 1, 2020.1 Elderly people and patients with chronic diseases are at increased risk of negative COVID-19 outcomes, including progression to severe disease, hospitalization, and death.2 , 3 New therapeutic options exist for COVID-19 disease, but along with these new therapies is the risk of drug-related adverse events that result from drug interactions with concomitantly taken medications.4 Long-term medication use is highly prevalent in the United States, especially among older adults and those with chronic conditions.5 Many drugs used to treat chronic diseases are known to have interactions with one another because of their effects on shared metabolic pathways.6, 7, 8, 9, 10, 11 The introduction of new COVID-19 therapies could further increase such risk, especially among those who use several medications concomitantly.12 Lopinavir/ritonavir, for example, previously used to treat COVID-19, was associated with high rates of drug-drug interactions (DDIs) and drug-related adverse events.13, 14, 15 A 2022 systematic review of drug interactions and adverse events from COVID-19 treatments found that ritonavir (and lopinavir) had the highest associations with DDIs in patients treated for COVID-19.15 In December 2021, ritonavir in combination with nirmatrelvir received emergency use authorization16 from the US Food and Drug Administration (FDA) for treatment of nonhospitalized patients with COVID-19 at risk of progression to severe disease.17, 18, 19 Before the COVID-19 epidemic, ritonavir use was limited to a comparatively small patient population of people living with HIV/AIDS.20 , 21 The risk of DDIs in the US population that may arise from use of this drug is yet to be quantified for the entire US population. Ritonavir is a protease inhibitor that acts as a pharmacokinetic boosting agent. It increases the plasma concentrations of certain medications by inhibiting cytochrome P350 3A4 (CYP3A4), an isoenzyme that plays a key role in the metabolism of up to 50% of all prescribed medications.20 , 22 DDIs due to ritonavir's inhibition of CYP3A4 can occur when ritonavir is coadministered with other CYP3A4-mediated medications (ie, inhibitors, inducers, or substrates of CYP3A4). CYP3A4 inhibitors reduce clearance of coadministered CYP3A4-mediated medications, leading to potentially toxic levels of the coadministered medication.13 , 23 , 24 Inducers increase clearance of coadministered medications, leading to potentially subtherapeutic drug concentrations and loss of therapeutic effect of the coadministered medication.25 , 26 When given alongside CYP3A4-mediated antimicrobial medications, inducers may contribute to the development of antimicrobial resistance.19 , 27 Ritonavir's inhibition of CYP3A4 results in hypotension, thrombosis, increased bleeding events, sedation and respiratory depression, and drug toxicity when coadministered with CYP3A4-mediated medications.13 , 24 Data are lacking on the magnitude of risk and severity of potential DDIs (pDDIs) that may occur from the use of ritonavir-containing COVID-19 therapy in the general population. It is essential to quantify population-level risk of DDI outcomes given widespread incidence of COVID-19 and plans to make treatments widely available and easily accessible. In this study, we address the paucity of pDDI data due to ritonavir use by estimating the potential prevalence and severity of DDIs associated with ritonavir-containing COVID-19 therapy in the US general population and by subgroups with risk for severe disease. Participants and Methods The primary measure in this study was the prevalence of pDDIs with ritonavir-containing medications among the US population, stratified by demographic characteristics and COVID-19 risk factors. Study participants were obtained from 2 waves of the National Health and Nutrition Examination Survey (NHANES). Participants were eligible if they were 18 years or older at the time of survey collection. Prevalence estimates among the sample were weighted to be generalizable to the US population using fasting sample weights, which were calculated by NHANES. The fasting sample weights were chosen as the appropriate weights in this study based on NHANES-recommended weighting practices.28 NHANES is a set of cross-sectional surveys that have been collected continuously in 2-year waves since 1999 to assess the health and nutrition of US adults and children.29 The survey includes data collected from questionnaires, examination and laboratory measures, and household interviews.29 Its sampling design supports generalization to the noninstitutionalized US population. Some population subgroups are intentionally oversampled in NHANES to improve reliability of subgroup analyses.29 Sample weights and best practices for their use are produced by NHANES biostatisticians for generalization of estimates to the US population.28 , 30 Because of the interruption of data collection by the COVID-19 pandemic, data for 2019 through March 2020 were combined with the complete 2017 to 2018 wave, ensuring a representative sample. This study combined the 2 most recent waves to ensure that study results were most applicable to the US population at the time of the COVID-19 pandemic. Prescription medication use is captured across all waves of data collection and has previously been used to estimate the prevalence of pDDIs in the US population.28 , 31 During the household interviews, interviewers asked participants, “In the past 30 days, have you used or taken medication for which a prescription is needed?” Affirmative responses by participants are followed up by a request from the interviewer to see medication containers for each medication reported. Prescription data collected during household surveys were used to estimate the prevalence of CYP3A4-mediated medications in the population and to subset this population by severity of pDDIs with a ritonavir-containing medication. The prevalence of pDDIs was therefore defined as the number of individuals with past 30-day use of at least 1 medication with a potential drug-drug interaction with a ritonavir-containing medication. CYP3A4-mediated medications and their expected interaction severity were assessed using 3 sources: the University of Liverpool's COVID-19 online drug interaction checker, Lexicomp, and the FDA fact sheet for nirmatrelvir/ritonavir.19 , 24 , 32 CYP3A4-mediated medications were categorized as having a contraindicated, major, moderate, or minor pDDI with ritonavir-containing medications (Table I ). Medications with contraindicated pDDI with ritonavir were defined as those identified as red using the Liverpool drug interaction checker, indicated as “contraindicated and/or avoid concomitant use” in the nirmatrelvir/ritonavir FDA fact sheet, or labeled “avoid combination” from Lexicomp. Medications with major pDDIs with ritonavir were defined as those not in the contraindicated group and either identified as amber using the Liverpool drug interaction checker or labeled “consider therapy modification” from Lexicomp. Medications with moderate pDDIs with ritonavir were defined as those not in the contraindicated or major groups and identified as yellow using the Liverpool drug interaction checker, indicated as “monitoring is needed” in the nirmatrelvir/ritonavir FDA fact sheet, or labeled “monitor therapy” from Lexicomp. Medications with minor pDDIs with ritonavir were defined as those assessed by 1 of the 3 sources and not in the contraindicated, major, or moderate groups or labeled “no action needed” from Lexicomp. In cases of disagreement among the 3 sources, medications were assigned to the highest severity category of the 3 sources. If a participant received >1 CYP3A4-mediated medication belonging to different severity categories, the participant was assigned to the highest pDDI severity category.Table I Definitions of potential DDI severity categories sourced from the University of Liverpool, Lexicomp, and FDA fact sheet. Table ISeverity Category Definition Contraindicated Any medication that is (1) identified as red using the University of Liverpool DDI checker OR (2) indicated as contraindicated and/or avoid concomitant use in the FDA fact sheet OR (3) “avoid combination” from Lexicomp Major Any medication that is (1) not in the contraindicated group AND (2) identified as amber using the University of Liverpool DDI checker OR “consider therapy modification” from Lexicomp Moderate Any medication that is (1) not in the contraindicated or major groups AND (2) identified as yellow using the University of Liverpool DDI checker OR indicated as monitoring is needed in the FDA fact sheet OR “monitor therapy” from Lexicomp Minor Any medication assessed by the University of Liverpool DDI checker, FDA fact sheet, or Lexicomp that is NOT in the contraindicated, major or moderate groups OR “no action needed” from Lexicomp DDI = drug-drug interaction; FDA = US Food and Drug Administration. Risk factors for progression to severe COVID-19 were obtained from published documents by the Centers for Disease Control and Prevention and include cancer, chronic obstructive pulmonary disease, chronic kidney disease (CKD), immunocompromised state from a solid organ transplant, obesity, dementia, hepatic disease, HIV, depression, serious heart conditions, sickle cell disease, current or past smoking, physical inactivity, pregnancy, and type 2 diabetes.33 Information on sickle cell disease and solid organ transplants are not collected in NHANES34 and so were not captured in this study. Dementia and tuberculosis were assessed or approximated in previous NHANES waves but were not measured in the 2015 to 2016 or 2017 to 2019 waves and so were excluded from this study. Risk factors were evaluated as the presence of at least 1 risk factor for progression to severe COVID-19 and by individual risk factors. Information regarding risk factors were assessed using self-reported questionnaire answers, examinations, and laboratory results, where available. Details of the survey questions used to assess for risk factors are included in the Appendix. pDDI prevalence was assessed among these risk factor subgroups and among those with older age (defined as age of ≥60 years at the time of the survey). Statins are very commonly used in the United States and have been recommended for temporary withholding while administering ritonavir-containing COVID-19 therapy by the US FDA.19 , 35 , 36 We conducted a sensitivity analysis to estimate the prevalence of pDDIs in the United States, excluding statins from the list of CYP3A4-mediated medications. Datasets used in this study can be found within the 2015 to 2016 and 2017 to March 2020 prepandemic data of NHANES (https://wwwn.cdc.gov/nchs/nhanes/).37 All data are deidentified and subjected to data processing, quality assessment, and disclosure review before being made publicly available; thus, no informed consent processes are required for conducting this analysis. NHANES is subject to the National Center for Health Statistics Institutional Review Board and has received approval for each wave of data collection (https://www.cdc.gov/nchs/nhanes/irba98.htm). All analyses were completed using SAS software, version 9.4 (SAS Institute, Cary, North Carolina). Results A total of 15,685 adults with a mean (SD) age of 49.0 (18.6) years were included in this study (Table II ). The sample was 51.5% female, 33.7% non-Hispanic White, and 48.6% privately insured (Table II). A total of 80.6% of study participants had at least 1 COVID-19 risk factor for progression to severe disease (Table II). After weighting to be representative of the US noninstitutionalized adult population, the mean (SE) age was 47.3 (0.5) years, 51.8% were female, 62.8% were non-Hispanic White, and 59.7% had private insurance (Table II). A total of 81.2% had at least 1 risk factor for progression to severe COVID-19 in the weighted sample (Table II).Table II Demographic characteristics and insurance types of adults aged ≥18 years among unweighted 2015-2020 NHANES participants and weighted US population.* Table IICharacteristic NHANES Waves 2015-2020 (n = 15,685) Weighted (n = 188,137,854) Age, mean (SD or SE), y 49.0 (18.6) 47.1 (0.5) Age group at index, y 18–44 6693 (42.7) 85,844,312 (45.6) 45–59 3669 (23.4) 49,496,317 (26.3) 60–69 2695 (17.2) 30,673,327 (16.3) 70–79 1570 (10.0) 14,946,436 (7.9) ≥80 1058 (6.7) 7,177,463 (3.8) Sex Female 8080 (51.5) 96,820,967 (51.5) Male 7605 (48.5) 91,316,887 (48.5) Race and ethnicity Non-Hispanic White 5284 (33.7) 117,556,853 (62.5) Non-Hispanic Black 3820 (24.4) 21,578,496 (11.5) Non-Hispanic Other 2597 (16.6) 18,868,648 (10.0) Hispanic 3984 (25.4) 30,133,857 (16.0) Insurance† Private 7618 (48.6) 110,957,524 (59.0) Medicare 3944 (25.1) 38,465,473 (20.4) Medicaid 2378 (15.2) 18,312,673 (9.7) Other 2652 (16.9) 38,910,980 (20.7) None or no record 4 (0.0) 7711 (0.0) Any COVID-19 risk factor 12,641 (80.6) 151,702,201 (81.2) NHANES = National Health and Nutrition Examination Survey. ⁎ Data are presented as number (percentage) of participants unless otherwise indicated. † Participants may have reported more than one insurance type. Study participants used a mean (SD) of 2.9 (1.8) pDDI medications per person, and once weighted to the sample, the US population used a mean (SE) of 2.5 (0.1) pDDI medications per person (Table III ). The weighted prevalence of any pDDI with ritonavir-containing medications in the US population was 45.3%, and 29.3% of the US population was estimated to have major or contraindicated pDDIs (Table III). Statins were commonly prescribed among participants, but only 26.2% of participants were observed to have a major or contraindicated pDDI from statin use alone (Supplemental Table I). After exclusion of statins from the list of pDDI medications, 21.0% of the US population was still observed to be at risk of major or contraindicated pDDIs (Table III).Table III Weighted prevalence of CYP3A4-mediated medications, pDDIs, and pDDI severity with ritonavir among the US population. Table IIIOutcome Prevalence Past 30-day use of CYP3A4-mediated medications, % 45.3 No. of CYP3A4-mediated medications used in past 30 days, mean (SD or SE) 2.5 (0.1) No. of CYP3A4-mediated medications used in past 30-days, median (IQR) 2 (1–3) Severity of pDDI with ritonavir, % of total population Contraindicated 20.6 Major 8.8 Moderate 5.4 Minor 10.6 Severity of pDDI with ritonavir excluding participants who use only statins and no other CYP3A4-mediated medications, % of total population Contraindicated 7.8 Major 13.2 Moderate 7.8 Minor 12.9 Suspected major or contraindicated pDDIs Past 30-day use of a CYP3A4-mediated medication with suspected major or contraindicated pDDIs, % 29.3 No. of CYP3A4-mediated medications with suspected major or contraindicated pDDIs used in past 30 days, mean (SD or SE) 1.6 (0.0) No. of CYP3A4-mediated medications with suspected major or contraindicated pDDIs used in past 30 days, median (IQR) 1 CYP3A4 = cytochrome P350 3A4; IQR = interquartile range; pDDIs = potential drug-drug interactions. The prevalence rates of major or contraindicated pDDIs were 32.7%, 28.4%, 25.4%, and 19.3% for non-Hispanic White, non-Hispanic Black, non-Hispanic other, and Hispanic members of the US population, respectively (Figure 1 ). Major or contraindicated pDDIs were observed in 34.5% of the US populations with any COVID-19 risk factor, and 60.2% of individuals 60 years or older were exposed to major or contraindicated pDDIs (Figure 1). Individuals with cancer, serious heart conditions, cerebrovascular disease, CKD, chronic obstructive pulmonary disease, diabetes, HIV, depression, and steroid or immunosuppressive agent use each had prevalence of major or contraindicated pDDIs >50% (Figure 1).Figure 1 Weighted prevalence of cytochrome P350 3A4–mediated medications with suspected major to contraindicated potential drug-drug interactions (pDDIs) among the US population by demographic characteristics and risk factors. Prevalence of major to contraindicated pDDIs among subgroups by age, sex, race, and COVID-19 risk factors are presented, along with this prevalence among the general US population for visual comparison (29.3%). CKD = chronic kidney disease; COPD = chronic obstructive pulmonary disease; eGFR = estimated glomerular filtration rate. Figure 1 Discussion In this study, we observed that 29.3% of the US population uses medications likely to have major or contraindicated pDDIs with ritonavir-containing COVID-19 therapy (Table II). Even after the exclusion of statins from the list of pDDI medications (considering that statins such as simvastatin can be halted during COVID-19 therapy),35 a significant proportion of the population remains at risk of DDIs if they receive a ritonavir-containing regimen. A total of 81.2% of the US population was also observed to have at least 1 risk factor for progression to severe COVID-19. Other studies have found similar findings using the same or comparable datasets (Table II).34 , 38 The high prevalence of COVID-19 risk factors in the US population emphasizes the importance of drug interaction risk assessment at the population level. Participants 60 years and older had a 60.2% prevalence of major or contraindicated pDDIs with ritonavir, and those with serious heart conditions, moderate CKD, severe CKD, diabetes, and HIV had 80.7%, 73.9%, 69.5%, 63.4%, and 68.5% prevalences, respectively, of suspected major or contraindicated pDDIs (Figure 1). The heightened probability of DDIs in these vulnerable patient groups should motivate careful assessments for polypharmacy and potential drug-drug interactions before prescribing COVID-19 medications.12 US stakeholders recommend dose adjustment and temporary withholding for certain contraindicated medications when prescribing ritonavir-containing COVID-19 treatments. However, in real-world clinical settings, it may be difficult to identify all concomitantly used medications, especially when care is fragmented, patients have low health literacy, or caregivers lack knowledge of drug interactions and proper withholding or adjustment practices.26 Dose adjustment or temporary withholding may also not be feasible if the benefits of treatment continuity outweigh the benefits of a ritonavir-containing COVID-19 medication. The National Institutes of Health guideline panel, for example, recommends alternative therapy to nirmatrelvir/ritonavir for patients receiving certain anticonvulsants, cardiovascular agents, and neuropsychiatric agents.35 Many of the medications used by participants in this study fall within these drug classes (Supplemental Table I), providing evidence that altering or temporary withholding of their treatments would not be recommended should they require treatment for severe COVID-19. As both a CYP3A4 inhibitor and substrate, ritonavir has the potential to lead to poor clearance of other CYP3A4 substrates and to be cleared too quickly when given alongside CYP3A4 inducers.19 Nirmatrelvir (given alongside ritonavir for COVID-19) is also a substrate of the CYP3A4 pathway.19 Prescribers should therefore consider both ritonavir's inhibiting impact on CYP3A4 substrates and the potential impacts of CYP3A4 inducers on ritonavir/nirmatrelvir therapeutic concentrations when treating COVID-19. Our study only considered ritonavir's impact on the CYP3A4 metabolic pathway, but given that ritonavir interacts with multiple drug pathways, including other cytochrome P450 and the p-glycoprotein pathways,6 , 25 treatment of COVID-19 with nirmatrelvir/ritonavir may have additional drug interaction implications outside the CYP3A4 pathway. The risk of pDDIs between medications and ritonavir-containing COVID-19 therapy due to its interaction with multiple pathways goes beyond what is described in this study. The discussion of the risk of pDDIs between prevalent medications and ritonavir-containing COVID-19 therapy from this study remains applicable even in the evolving pandemic setting. Although other studies have warned against the DDIs that may arise from ritonavir alongside long-term medications,39 , 40 this study is the first to our knowledge to provide an estimate of pDDI risk in the general population. NHANES presented the best opportunity to address this study's aims because of its generalizability, public health relevance, and collection of nearly all variables relevant to COVID-19 risk factors and medications. It has also been previously used to estimate key metrics applicable to the population during COVID-19.34 , 41 Study Limitations This study used the 2015 to March 2020 NHANES waves, the 2 most recent data collection waves, to ensure the relevance of conclusions to the US therapeutic market at the time of the COVID-19 pandemic. Findings may have been more robust if NHANES data from 2020 onward were used, but current data are unavailable at this time. It is possible that changing trends in therapeutics and certain risk factors, such as depression, due to the pandemic will have affected the estimates presented in this study, but it is impossible to tell the direction of such changes. In addition, the 2015 to March 2020 NHANES waves did not collect data on dementia, tuberculosis, cystic fibrosis, or organ transplant. This limitation could have led to an underestimation of overall risk factors and a gap in the knowledge of pDDI risk for certain patient groups, for example, among patients with a history of organ transplant receiving tacrolimus or cyclosporine, which are contraindicated for coadministration with ritonavir-containing COVID-19 medications.24 Additionally, because medication data in NHANES are based on interviewers’ review of prescriptions, the survey misses important medications that are typically administered in the inpatient settings, in physicians’ offices, purchased as over-the-counter medications, or used recreationally, many of which have known interactions with ritonavir-containing regimens.24 Furthermore, changing prescribing patterns directly related to infection with COVID-19, such as increased prescriptions of antimicrobials to attempt to treat COVID-19, may increase the potential for DDIs to occur between medications meant to treat the COVID-19 infection.42 Thus, study results may underestimate the prevalence of CYP3A4 medications and pDDIs in the United States during the COVID-19 pandemic. The prevalence of risk factors and CYP3A4-mediated medications that NHANES does not account for should be investigated in the future. Conclusions Approximately 30% of the US population may be at risk for major or contraindicated DDIs if treated with ritonavir-containing COVID-19 therapy. Study findings emphasize the need for skilled assessment of pDDIs before prescribing or dispensing ritonavir-containing COVID-19 therapy. Clinical decisions for the appropriate treatment of patients with COVID-19 should be informed by risk factors for progression to severe disease, complexity of the management of underlying diseases, the potential of DDIs, the feasibility of managing DDIs, and potential adverse outcomes of failing to identify and/or appropriately manage DDIs associated with ritonavir-containing COVID-19 therapy. Alternative therapies should be considered when DDIs preclude the use of ritonavir-containing therapy. Supplementary Material Details of the survey questions utilized to assess for risk factors Risk factors were evaluated as participants having at least one risk factor for progression to severe COVID-19 and by individual risk factors. Cancer was defined by an affirmative response to: “Ever told you had cancer or malignancy.” Cerebrovascular disease was defined by an affirmative response to “Ever told you had a stroke.” CKD was defined by urinary albumin-creatinine ratio (UACR) ≥ 30 mg/g or eGFR < 60 mL/min/1.73m2 or an affirmative response to: “Ever told you had weak or failing kidneys” or “received dialysis in the past 12 months”. CKD was further stratified by moderate to severe among those with eGFR available; moderate CKD was defined as eGFR 30-59 mL/min/1.73m2, and severe CKD was defined as eGFR < 30 mL/min/1.73m2.1,2 eGFR was calculated from serum creatinine, age, and sex using the 2021 CKD-EPI equation recommended by the American Society of Nephrology (ASN).3 COPD was defined by an affirmative response to: “Ever told you had emphysema” or “Ever told you had COPD” or “Ever told you have chronic bronchitis”. Hepatic disease was defined by an affirmative response to “Ever told you had any kind of liver condition?” or a value of aspartate aminotransferase or alanine aminotransferase 2x the upper limit of normal. Normal ranges for AST and ALT are 5-40U/L and 7-56 U/L, respectively. Diabetes was defined by an HbA1c ≥ 6.5% or a fasting plasma glucose of ≥ 126 mg/dL or an affirmative response to “A doctor told you have diabetes”. Serious heart condition was defined by an affirmative response to: “Ever told you had coronary heart disease” or “Ever told you had a heart attack” or “Ever told you had congestive heart failure.” HIV was defined as a positive result for HIV confirmation or antibody test. Depression was defined by an affirmative response to: “Do you take medication for depression”. Obesity was defined by a BMI measurement ≥ 30 kg/m2. Pregnancy was defined by an affirmative response to: “Currently pregnant or breastfeeding.” Physical inactivity was defined as an affirmative response to: “To lower your risk for certain diseases, during the past 12 months ever told by a doctor or health professional to: increase your physical activity or exercise.” Smoking was defined as an affirmative response to “Smoked at least 100 cigarettes in life,” then assessed by response to “Do you now smoke cigarettes?” as current smoker (response “Every day” or “Some days”) or past smoker (response “Not at all”). Steroid or immunosuppressive medication use was defined as an affirmative response to: “Ever taken any prednisone or cortisone pills nearly every day for a month or longer.” Interviews for HIV, depression, and steroid/immunosuppressive medication were only done during one NHANES wave. Denominators and weighting were specific to the singular wave for these variables. Table S1–S3 .1 Chronic Kidney Disease (CKD) Surveillance System. Accessed March 18, 2022. https://nccd.cdc.gov/CKD/TopicHome/PrevalenceIncidence.aspx 2 Kibria GMA, Crispen R. Prevalence and trends of chronic kidney disease and its risk factors among US adults: An analysis of NHANES 2003-18. Prev Med Rep. 2020;20:101193. doi:10.1016/j.pmedr.2020.101193 3 Delgado, C, Baweja, M, Crews, DC, Eneanya, ND, Gadegbeku, CA, Inker, LA, Mendu, ML, Miller, WG, Moxey-Mims, MM, Roberts, GV, St. Peter, WL, Warfield, C, Powe, NR. A Unifying Approach for GFR Estimation: Recommendations of the NKF-ASN Task Force on Reassessing the Inclusion of Race in Diagnosing Kidney Disease. JASN. 2021;32(12):2994-3015. DOI: 10.1681/ASN.2021070988 Supplementary Table S1 Prevalence of statin use alone and top 20 most prevalent CYP3A4-mediated medications with suspected major or contraindicated pDDIs among the unweighted NHANES 2015-March 2020 sample with any major or contraindicated pDDI. Supplementary Table S1 NHANES waves 2015-2019 n % Total persons noted with major or contraindicated pDDI (n) 4,908 Use of statin alone 1,287 26.2% ATORVASTATIN 1,406 28.6% AMLODIPINE 1,169 23.8% SIMVASTATIN 819 16.7% TAMSULOSIN 366 7.5% CLOPIDOGREL 334 6.8% ROSUVASTATIN 320 6.5% TRAMADOL 281 5.7% TRAZODONE 220 4.5% ALPRAZOLAM 218 4.4% WARFARIN 185 3.8% CLONAZEPAM 153 3.1% DILTIAZEM 142 2.9% LOVASTATIN 139 2.8% ZOLPIDEM 136 2.8% FLUTICASONE 106 2.2% HYDROXYZINE 106 2.2% APIXABAN 105 2.1% QUETIAPINE 104 2.1% NIFEDIPINE 91 1.9% HYDROCODONE 87 1.8% Supplementary Table S2 Weighted prevalence of COVID-19 risk factors among the US population, overall and by demographic category. Supplementary Table S2 Overall Age 60+ Female Male Non-Hispanic White Non-Hispanic Black Non-Hispanic Other Hispanic Subgroup % % % % % % % % Any COVID-19 Risk Factor 81.2% 91.6% 80.6% 81.7% 82.8% 81.4% 73.7% 79.4% Cancer 10.3% 25.0% 11.5% 8.9% 13.2% 5.0% 7.8% 4.0% Serious Heart Conditions 6.2% 16.0% 5.1% 7.4% 6.7% 6.8% 7.0% 3.6% Cerebrovascular Disease 3.2% 7.8% 3.4% 3.0% 3.3% 4.5% 3.4% 1.8% CKD (affirmative questionnaire response, UACR ≥ 30mg/g or eGFR < 60mL/min/1.73m2) 14.0% 27.8% 15.4% 12.5% 13.7% 18.4% 11.8% 13.2% Lab-confirmed CKD only (UACR ≥ 30mg/g or eGFR < 60mL/min/1.73m2 12.7% 26.7% 14.1% 11.3% 12.6% 17.6% 10.3% 11.5% Moderate (eGFR 30-59) 4.2% 13.6% 4.9% 3.4% 4.7% 6.1% 2.3% 1.6% Severe (eGFR <30) 0.5% 1.3% 0.6% 0.3% 0.3% 1.7% 0.1% 0.3% COPD 8.2% 14.3% 9.6% 6.7% 9.3% 7.7% 7.3% 4.7% Smoking 43.2% 49.6% 36.5% 50.4% 47.2% 39.8% 36.3% 34.2% Current smoker 17.1% 10.7% 15.0% 19.3% 16.2% 23.3% 18.2% 15.2% Past smoker 26.1% 39.0% 21.5% 31.1% 31.0% 16.5% 18.0% 19.0% Obesity 39.7% 40.7% 41.9% 37.3% 39.1% 47.6% 26.7% 44.3% Diabetes 15.6% 29.5% 13.8% 17.5% 14.6% 18.5% 15.1% 17.8% Pregnancy 0.9% 0.0% 1.7% 0.0% 0.8% 0.9% 0.9% 1.3% Hepatic disease 4.9% 6.3% 4.3% 5.6% 4.7% 2.6% 6.4% 6.5% HIV 0.2% 0.0% 0.1% 0.2% 0.1% 0.5% 0.0% 0.1% Depression 6.4% 6.4% 7.7% 3.5% 6.8% 3.5% 4.9% 3.1% Physical inactivity 39.2% 50.2% 43.9% 34.1% 37.6% 42.3% 41.1% 41.6% Steroid or immunosuppressive medication 3.1% 3.0% 1.8% 1.3% 1.4% 2.0% 2.0% 1.5% Supplementary Table S3 Prevalence of CYP3A4-mediated medications with suspected major or contraindicated pDDIs among the US population, by risk factor, stratified by demographic category. Supplementary Table S3 Total weighted to US population Age 60+ Female Male Non-Hispanic White Non-Hispanic Black Non-Hispanic Other Hispanic All participants % % % % % % % % % Total 29.3% 60.2% 28.8% 29.9% 32.7% 28.4% 25.4% 19.3% 31.3% Any COVID-19 Risk Factor 34.5% 62.8% 33.9% 35.1% 37.8% 32.9% 33.3% 22.7% 36.8% Cancer 56.2% 64.9% 47.3% 68.4% 55.5% 65.5% 68.5% 41.6% 56.8% Serious Heart Conditions 80.7% 87.7% 73.5% 86.0% 81.8% 78.4% 87.0% 67.8% 79.8% Cerebrovascular disease 80.7% 86.2% 80.8% 80.5% 86.6% 60.5% 86.9% 66.7% 73.1% CKD (affirmative questionnaire response, UACR ≥ 30mg/g or eGFR < 60mL/min/1.73m2) 55.6% 75.1% 54.1% 57.6% 59.1% 54.6% 56.1% 42.4% 56.7% Lab-confimred CKD only (UACR ≥ 30mg/g or eGFR < 60mL/min/1.73m2) 55.7% 75.0% 53.6% 58.4% 59.7% 54.0% 55.1% 40.8% 56.6% Moderate CKD (eGFR 30-59) 73.9% 77.3% 68.9% 81.6% 75.2% 66.9% 84.9% 68.5% 71.5% Severe CKD (eGFR <30) 69.5% 77.8% 69.8% 68.8% 71.7% 63.2% 100.0% 76.0% 75.0% COPD 56.6% 66.6% 52.0% 63.5% 58.6% 52.5% 58.8% 43.6% 60.2% Smoking 37.3% 65.7% 39.1% 35.9% 39.9% 32.8% 38.8% 26.0% 39.4% Current smoker 30.4% 61.6% 35.2% 26.5% 33.2% 27.7% 34.9% 18.3% 29.5% Past smoker 41.8% 66.8% 41.8% 41.8% 43.4% 39.9% 42.6% 32.1% 47.2% Obesity 34.6% 66.2% 33.9% 35.4% 38.6% 33.4% 30.9% 23.0% 36.6% Diabetes 63.4% 78.4% 61.0% 65.4% 70.7% 56.4% 58.6% 47.9% 63.0% Pregnancy 3.8% 3.8% 3.3% 10.9% 7.1% 0.0% 5.2% Hepatic diease 40.8% 65.3% 41.0% 40.7% 46.3% 46.9% 24.9% 33.5% 47.7% HIV 68.5% 69.7% 68.0% 100.0% 58.3% 42.8% 52.9% Depression 65.0% 72.5% 65.4% 64.1% 65.7% 67.0% 68.0% 54.3% 66.1% Physical inactivity 44.3% 68.9% 40.2% 49.8% 48.2% 42.6% 40.5% 33.8% 46.0% Steroid or immunosuppressive medication 55.6% 80.0% 53.3% 58.8% 55.4% 63.1% 41.0% 61.1% 63.2% Acknowledgments We acknowledge Seth Kuranz for his contribution to the protocol of this study. All authors contributed to the research involved in the manuscript and article preparation. Ebuwa Igho-Osagie, Kaylen Brzozowski, Harry Jin, Jeffrey Brown, and Amy Puenpatom contributed to study conceptualization. Ebuwa Igho-Osagie, Kaylen Brzozowski, Harry Jin, Jeffrey Brown, Marissa Grifasi Williams, and Amy Puenpatom contributed to study methodology, review of results, and manuscript preparation and finalization. Kaylen Brzozowski and Harry Jin contributed to data analysis with significant input from Ebuwa Igho-Osagie, Marissa Grifasi Williams, and Amy Puenpatom. Funding Sources Work for this study and the express track fee were funded by Merck & Co Inc. The study team included members from the funder, and these team members contributed to the study design, interpretation of analysis, report writing, and decision to submit for publication. Declaration of Interest None declared. ==== Refs References 1 Centers for Disease Control and Prevention. COVID data tracker. Published March 28, 2020. Accessed July 12, 2022. https://covid.cdc.gov/covid-data-tracker 2 Choi YJ Park JY Lee HS Variable effects of underlying diseases on the prognosis of patients with COVID-19 PloS One 16 2021 e0254258 3 Emami A Javanmardi F Pirbonyeh N Akbari A Prevalence of underlying diseases in hospitalized patients with COVID-19: a systematic review and meta-analysis Arch Acad Emerg Med 8 2020 e35 32232218 4 US Food and Drug Administration. Coronavirus (COVID-19) drugs. https://www.fda.gov/drugs/emergency-preparedness-drugs/coronavirus-covid-19-drugs. 5 National Center for Health Statistics. FastStats: Therapeutic drug use. https://www.cdc.gov/nchs/fastats/drug-use-therapeutic.htm. 6 US Food and Drug Administration. Drug development and drug interactions \| Table of substrates, inhibitors and inducers. https://www.fda.gov/drugs/drug-interactions-labeling/drug-development-and-drug-interactions-table-substrates-inhibitors-and-inducers. 7 Zhou SF Xue CC Yu XQ Li C Wang G Clinically important drug interactions potentially involving mechanism-based inhibition of cytochrome P450 3A4 and the role of therapeutic drug monitoring Ther Drug Monit 29 2007 687 710 PMID:18043468 18043468 8 Low Y Setia S Lima G Drug-drug interactions involving antidepressants: focus on desvenlafaxine Neuropsychiatr Dis Treat 14 2018 567 580 PMID:29497300PMCID: PMC5822840 29497300 9 van Leeuwen RW Brundel DH Neef C van Gelder T Mathijssen RH Burger DM Jansman FG Prevalence of potential drug-drug interactions in cancer patients treated with oral anticancer drugs Br J Cancer 108 2013 1071 1078 Epub 2013 Feb 14. PMID:23412102PMCID: PMC3619066 23412102 10 Wedemeyer RS Blume H Pharmacokinetic drug interaction profiles of proton pump inhibitors: an update Drug Saf 37 2014 201 211 PMID:24550106PMCID: PMC3975086 24550106 11 Shahzadi A Sonmez I Kose C Oktan B Alagoz S Sonmez H Hussain A Akkan AG The prevalence of potential drug-drug interactions in CKD: a retrospective observational study of Cerrahpasa nephrology unit Medicina (Kaunas) 58 2022 183 PMID:35208508PMCID: PMC8875967 35208508 12 Hodge C Marra F Marzolini C Drug interactions: a review of the unseen danger of experimental COVID-19 therapies J Antimicrob Chemother 75 2020 3417 3424 32750131 13 Rezaee H Pourkarim F Pourtaghi-Anvarian S Entezari-Maleki T Asvadi-Kermani T Nouri-Vaskeh M Drug-drug interactions with candidate medications used for COVID-19 treatment: an overview Pharmacol Res Perspect 9 2021 e00705 PMID:33421347PMCID: PMC7796804 33421347 14 Stader F Khoo S Stoeckle M Back D Hirsch HH Battegay M Marzolini C Stopping lopinavir/ritonavir in COVID-19 patients: duration of the drug interacting effect J Antimicrob Chemother 75 2020 3084 3086 PMID:32556272PMCID: PMC7337877 32556272 15 Conti V Sellitto C Torsiello M Identification of drug interaction adverse events in patients with COVID-19: a systematic review JAMA Netw Open 5 2022 e227970 16 Office of the Commissioner, US Food and Drug Administration. Emergency use authorization. Published online March 2, 2022. Accessed March 6, 2022. https://www.fda.gov/emergency-preparedness-and-response/mcm-legal-regulatory-and-policy-framework/emergency-use-authorization. 17 US Food and Drug Administration Coronavirus (COVID-19) Update: FDA authorizes drug combination for treatment of COVID-19 2022 Accessed March 7, 2022 https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-drug-combination-treatment-covid-19 18 US Food and Drug Administration. FDA fact sheet for healthcare providers: emergency use authorization for Lagevrio (molnupiravir) capsules. Accessed August 8, 2022. https://www.fda.gov/media/155054/download. 19 US Food and Drug Administration. FDA fact sheet for healthcare providers: Emergency use authorization for Paxlovid. Accessed March 7, 2022. https://www.fda.gov/media/155050/download. 20 Talha B Dhamoon AS Ritonavir [Updated 2022 Jun 18] StatPearls [Internet] 2022 StatPearls Publishing Treasure Island (FL) Jan-. Available from https://www.ncbi.nlm.nih.gov/books/NBK544312/ 21 Centers for Disease Control and Prevention. HIV Nexus clinician resources: HIV treatment and results. https://www.cdc.gov/hiv/clinicians/treatment/treatment-clinicians.html. 22 Zanger UM Schwab M Cytochrome P450 enzymes in drug metabolism: regulation of gene expression, enzyme activities, and impact of genetic variation Pharmacol Ther 138 2012 103 141 23 US Food and Drug Administration. Drug development and drug interactions \| Table of substrates, inhibitors and inducers. Accessed August 8, 2022. https://www.fda.gov/drugs/drug-interactions-labeling/drug-development-and-drug-interactions-table-substrates-inhibitors-and-inducers#table3-1. 24 University of Liverpool COVID-19 drug interactions 2022 Accessed March 7 https://www.covid19-druginteractions.org/checker 25 Zhou S-F Xue CC Yu X-Q Li C Wang G Clinically important drug interactions potentially involving mechanism-based inhibition of Cytochrome P450 3A4 and the role of therapeutic drug monitoring Ther Drug Monit 29 2007 687 710 18043468 26 Marzolini C Kuritzkes DR Marra F Boyle A Gibbons S Flexner C Pozniak A Boffito M Waters L Burger D Back D Khoo S Prescribing nirmatrelvir-ritonavir: how to recognize and manage drug-drug interactions Ann Intern Med 175 2022 744 746 Epub 2022 Mar 1PMID:35226530PMCID: PMC8890619 35226530 27 University of Liverpool Cancer drug interactions 2023 Accessed Feb 7 https://cancer-druginteractions.org/checker 28 Centers for Disease Control and Prevention. NHANES about NHANES. Accessed September 15, 2022. https://www.cdc.gov/nchs/nhanes/about_nhanes.htm. 29 US Department of Health and Human Services. NHANES survey methods and analytic guidelines. Published 2021. Accessed December 24, 2021. https://wwwn.cdc.gov/nchs/nhanes/analyticguidelines.aspx#estimation-and-weighting-procedures. 30 Centers for Disease Control and Prevention. NHANES tutorials module 3: weighting. Accessed July 12, 2022. https://wwwn.cdc.gov/nchs/nhanes/tutorials/module3.aspx. 31 Qato DM Alexander GC Guadamuz JS Lindau ST Prescription medication use among children and adolescents in the United States Pediatrics 142 2018 e20181042 32 Lexicomp. https://www.wolterskluwer.com/en/solutions/lexicomp 33 Centers for Disease Control and Prevention. COVID-19, people with certain medical conditions. Updated May 2, 2022. Accessed March 7, 2022. https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/people-with-medical-conditions.html. 34 Ajufo E Rao S Navar AM Pandey A Ayers CR Khera A U.S. population at increased risk of severe illness from COVID-19 Am J Prev Cardiol 6 2021 100156 35 National Institute of Health Drug-drug interactions between ritonavir-boosted nirmatrelvir (Paxlovid) and concomitant medications 2022 May 13Accessed July 12, 2022 https://www.covid19treatmentguidelines.nih.gov/therapies/antiviral-therapy/ritonavir-boosted-nirmatrelvir–paxlovid-/paxlovid-drug-drug-interactions/ 36 Gu Q Paulose-Ram R Burt VL Kit BK Prescription cholesterol-lowering medication use in adults aged 40 and over: United States, 2003–2012 2014 National Center for Health Statistics Hyattsville, MD NCHS data brief, no 177 37 Centers for Disease Control and Prevention (CDC). National Center for Health Statistics (NCHS). National Health and Nutrition Examination Survey Data. Hyattsville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, [2015-2016] [https://wwwn.cdc.gov/nchs/nhanes/continuousnhanes/default.aspx?Cycle=2017-2020] [2017-March 2020] [https://wwwn.cdc.gov/nchs/nhanes/continuousnhanes/default.aspx?BeginYear=2015] 38 Ahrenfeldt LJ Nielsen CR Möller S Christensen K Lindahl-Jacobsen R Burden and prevalence of risk factors for severe COVID-19 in the ageing European population - a SHARE-based analysis Z Gesundh Wiss 2021 Apr 11 1 10 Epub ahead of print. PMID:33868899PMCID: PMC8036158 39 SK SR P AA B S Kalala KP Pm A Sabarathinam S Drug interaction risk between cardioprotective drugs and drugs used in treatment of COVID-19: a evidence-based review from six databases Diabetes Metab Syndr 16 2022 102451 Epub 2022 Mar 7. PMID:35279008PMCID: PMC8898923 40 Marzolini C Kuritzkes DR Marra F Boyle A Gibbons S Flexner C Pozniak A Boffito M Waters L Burger D Back DJ Khoo S Recommendations for the management of drug-drug interactions between the COVID-19 antiviral nirmatrelvir/ritonavir (Paxlovid) and comedications Clin Pharmacol Ther 112 2022 1191 1200 Epub 2022 Jun 7. PMID:35567754PMCID: PMC9348462 35567754 41 Seligman B Ferranna M Bloom DE Social determinants of mortality from COVID-19: a simulation study using NHANES PLoS Med 18 1 2021 e1003490 Erratum in: PLoS Med. 2021;18(12):e1003888. PMID:33428624PMCID: PMC7799807 42 Langford BJ So M Raybardhan S Leung V Soucy JR Westwood D Daneman N MacFadden DR Antibiotic prescribing in patients with COVID-19: rapid review and meta-analysis Clin Microbiol Infect 27 4 2021 520 531 Epub 2021 Jan 5. PMID:33418017PMCID: PMC7785281 33418017
PMC010xxxxxx/PMC10037915.txt	==== Front Am J Transplant Am J Transplant American Journal of Transplantation 1600-6135 1600-6143 The Author(s). Published by Elsevier Inc. on behalf of American Society of Transplantation & American Society of Transplant Surgeons. S1600-6135(23)00357-X 10.1016/j.ajt.2023.03.014 Original Article Persistent SARS-CoV-2–specific immune defects in kidney transplant recipients following third mRNA vaccine dose Werbel William A. 1∗ Karaba Andrew H. 1 Chiang Teresa Po-Yu 2 Massie Allan B. 34 Brown Diane M. 1 Watson Natasha 5 Chahoud Maggie 1 Thompson Elizabeth A. 1 Johnson Aileen C. 6 Avery Robin K. 1 Cochran Willa V. 1 Warren Daniel 2 Liang Tao 1 Fribourg Miguel 7 Huerta Christopher 8 Samaha Hady 8 Klein Sabra L. 8 Bettinotti Maria P. 10 Clarke William A. 10 Sitaras Ioannis 9 Rouphael Nadine 8 Cox Andrea L. 1811 Bailey Justin R. 1 Pekosz Andrew 9 Tobian Aaron A.R. 10 Durand Christine M. 1 Bridges Nancy D. 5 Larsen Christian P. 6 Heeger Peter S. 12 Segev Dorry L. 34 on behalf of the CPAT investigators 1 Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA 2 Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA 3 Department of Surgery, New York University Grossman School of Medicine, New York, New York, USA 4 Department of Population Health, New York University Grossman School of Medicine, New York, New York, USA 5 National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA 6 Department of Surgery, Emory University, Atlanta, Georgia, USA 7 Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, New York, USA 8 Department of Medicine, Emory University, Atlanta, Georgia, USA 9 W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA 10 Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA 11 Bloomberg Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA 12 Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA ∗ Corresponding author. Johns Hopkins School of Medicine, 2000 E. Monument Street, Baltimore, MD, 21205, USA. 24 3 2023 6 2023 24 3 2023 23 6 744758 30 1 2023 17 3 2023 17 3 2023 © 2023 The Author(s) 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Kidney transplant recipients (KTRs) show poorer response to SARS-CoV-2 mRNA vaccination, yet response patterns and mechanistic drivers following third doses are ill-defined. We administered third monovalent mRNA vaccines to n = 81 KTRs with negative or low-titer anti-receptor binding domain (RBD) antibody (n = 39 anti-RBDNEG; n = 42 anti-RBDLO), compared with healthy controls (HCs, n = 19), measuring anti-RBD, Omicron neutralization, spike-specific CD8+%, and SARS-CoV-2–reactive T cell receptor (TCR) repertoires. By day 30, 44% anti-RBDNEG remained seronegative; 5% KTRs developed BA.5 neutralization (vs 68% HCs, P < .001). Day 30 spike-specific CD8+% was negative in 91% KTRs (vs 20% HCs; P = .07), without correlation to anti-RBD (rs = 0.17). Day 30 SARS-CoV-2–reactive TCR repertoires were detected in 52% KTRs vs 74% HCs (P = .11). Spike-specific CD4+ TCR expansion was similar between KTRs and HCs, yet KTR CD8+ TCR depth was 7.6-fold lower (P = .001). Global negative response was seen in 7% KTRs, associated with high-dose MMF (P = .037); 44% showed global positive response. Of the KTRs, 16% experienced breakthrough infections, with 2 hospitalizations; prebreakthrough variant neutralization was poor. Absent neutralizing and CD8+ responses in KTRs indicate vulnerability to COVID-19 despite 3-dose mRNA vaccination. Lack of neutralization despite CD4+ expansion suggests B cell dysfunction and/or ineffective T cell help. Development of more effective KTR vaccine strategies is critical. (NCT04969263) Graphical abstract Image 1 Keywords SARS-CoV-2 kidney transplant vaccination immunogenicity antibody clinical trial Abbreviations %ACE2i percent ACE2 inhibition anti-RBD anti-receptor binding domain antibody anti-RBDNEG negative anti-receptor binding domain antibody after 2 vaccine doses anti-RBDLO low-titer anti-receptor binding domain antibody after 2 vaccine doses AUC area under the curve CPAT COVID-19 Protection After Transplant HC healthy control IQR interquartile range KTR kidney transplant recipient mAb monoclonal antibody MHC major histocompatibility complex MIRA multiplex identification of antigen-specific T cell receptors MMF mycophenolate nAb neutralizing antibody NT50 nAb titer PBMC peripheral blood mononuclear cell RVE robust variance estimator TCR T cell receptor ==== Body pmc1 Introduction Kidney transplant recipients (KTRs) demonstrate poorer humoral1 and cellular immunogenicity2 , 3 following primary mRNA SARS-CoV-2 vaccination and endure higher rates of vaccine breakthrough.4 Neutralizing antibody (nAb) is the best available correlate of protection against SARS-CoV-2 infection,5 approximated by the clinically accessible anti-receptor binding domain (anti-RBD) antibody biomarker.6 High levels of nAb, however, are required for KTRs to neutralize Omicron subvariants.7 , 8 Associations with anti-RBD response in KTRs are well defined, including the negative impact of immunosuppressive regimens containing MMF.9, 10, 11 Anti-RBD level has also emerged as a powerful predictor of response to additional vaccine doses,12, 13, 14 with the potential to identify subgroups at higher risk for COVID-19 breakthrough15, 16, 17 and the need for immunoprophylactic interventions. The determinants and clinical impact of T cell responses induced by SARS-CoV-2 vaccines are less well delineated, in part owing to use of varying assays and metrics across studies. Additionally, discordance between antibody and T cell response has been reported in 0% to 50% of transplant recipients.18, 19, 20, 21 These patterns of humoral and/or cellular anti-SARS-CoV-2 immune responses and their underlying mechanistic drivers remain incompletely characterized. It is therefore uncertain whether immunoprotection against COVID-19 is achieved among KTRs following full (ie, 3-dose) vaccination, particularly among vulnerable KTRs who do not develop high-level anti-RBD. Given these knowledge gaps, we enrolled a homogenous KTR cohort with poor anti-RBD response following 2-dose mRNA vaccination in a clinical trial to determine the effects of third vaccination on (1) anti-RBD and variant neutralization, (2) SARS-CoV-2–specific T cell expansion using 2 complementary assays, and (3) global patterns of immune responses as compared with healthy controls (HCs). Clinical and immunological associations with vaccine breakthroughs were recorded. 2 Methods 2.1 Participants and design 2.1.1 Study background and design The COVID-19 Protection After Transplant (CPAT) trials were funded by the National Institutes of Health to investigate the safety and immunogenicity of SARS-CoV-2 vaccination strategies in solid organ transplant recipients. The single-arm, open-label trial described herein began August 10, 2021 to test immune responses to additional (third) homologous mRNA vaccination in KTRs who failed to respond to 2 prior mRNA vaccinations. “Failure to respond” was defined as negative (<0.8 U/mL, anti-RBDNEG) or low-titer (0.8 to 50 U/mL, anti-RBDLO) on the Roche Elecsys anti-SARS-CoV-2 S assay; this threshold was chosen given the minimal probability of neutralizing ancestral SARS-CoV-222 , 23 (Supplement). Participants included adult, kidney-only recipients on stable calcineurin inhibitor-based immunosuppression, without major graft dysfunction or organ rejection within 6 months; full criteria are listed at ClinicalTrials.gov (NCT04969263), and the study flow diagram is presented in Supplementary Figure S1. The primary immunogenicity outcome was day 30 anti-RBD, stratified by day 0 serostatus (anti-RBDNEG/anti-RBDLO), given anticipated differential responses.14 , 24 Secondary outcomes included SARS-CoV-2 variant neutralization and cellular responses. Safety outcomes included reactogenicity and alloimmune events. Serial monitoring for SARS-CoV-2 infection occurred via polymerase chain reaction testing of nasal swabs and anti-nucleocapsid antibody testing at days 30, 90, 180, and 365; symptom screening occurred at each visit, and continuous for-cause testing was performed via clinical teams. This trial was approved by the Johns Hopkins University IRB (IRB00288774); participants provided written informed consent. 2.1.2 Healthy control (HC) cohort In a separate, single-center prospective cohort of adult health care workers undergoing mRNA vaccination, samples were collected on day 0 and day 30 following third mRNA vaccine doses (Emory Vaccine Center, IRB#00002061). Third vaccines were administered October 2021 to November 2021, overlapping the CPAT study period; participants provided informed consent. 2.2 Antibody and neutralization assays 2.2.1 Anti-RBD antibody Anti-RBD was measured using the semiquantitative Roche Elecsys anti-SARS-CoV-2 S pan-immunoglobulin electrochemiluminesence immunoassay. Anti-RBD in U/mL correlates ∼1:1 with World Health Organization binding antibody units. Per manufacturer, <0.8 U/mL was reported as negative (lower limit of quantification 0.4 U/mL). All samples were up-front diluted 1:50 to avoid prozone (“hook”) effects and then serially diluted until 2 equivalent signals (±10%) were obtained, with the first value utilized. 2.2.2 ACE2 inhibition assays (surrogate neutralization) Neutralization was measured using the Meso Scale Discovery, which quantifies plasma inhibition of ACE2 binding to the full-length SARS-CoV-2 spike protein. ACE2 Meso Scale Discovery V-PLEX SARS-CoV-2 Panels 23/25/27/29/32 pre-coated with spike expressing mutations corresponding to SARS-CoV-2 variants were incubated with participant plasma; human ACE2 protein conjugated with light-emitting label was then added. If the plasma fully bound spike and blocked ACE2 binding, no light was emitted during the stimulation phase (100% inhibition; full neutralization). However, if there was no binding of spike by plasma, ACE2 was fully bound and illuminated during plate activation (0% inhibition; no neutralization). In vaccinated solid organ transplant recipients, ≥20% to 25% ACE2 inhibition (%ACE2i) on this high-throughput assay is associated with live virus nAb, including vs Omicron subvariants.25 , 26 2.2.3 Live virus neutralization Live ancestral, Delta, and Omicron BA.1 nAb was assessed in a subset of KTRs (Supplementary Section 2.2, Fig. S2). VeroE6-TMPRSS2 cells were cultured and incubated in transport media from SARS-CoV-2–infected patients27 for RNA extraction and sequencing. The viral titer of VeroE6-TMPRSS2 cells was determined using 50% tissue culture infectious dose assays.28 nAb levels were determined using 2-fold plasma dilutions29 with the addition of 1 × 104 tissue culture infectious dose/mL virus. Samples were incubated at 37˚C for 2 days (or until complete cytopathic effect); cells were then fixed, incubated, and stained. nAb titer (NT50) was calculated as the highest serum dilution that eliminated the cytopathic effect in 50% wells; area under the curve (AUC) was calculated using GraphPad Prism to provide a continuous measure of nAb. (+)nAb was defined as >1:20 NT50 and high-level nAb as >1:160 NT50. 2.3 Cellular analyses and methodology 2.3.1 SARS-CoV-2 spike-specific CD8+ memory T cell response Peripheral blood mononuclear cells (PBMCs) from HLA-A∗02:01+ KTRs (n = 33) were isolated and analyzed by flow cytometry for SARS-CoV-2 spike-specific CD8+ T cell responses using HLA-peptide pentamers (Supplement, Section 2.3). Cells were washed and stained with 4 biotinylated MHC class I pentamers corresponding to immunodominant SARS-CoV-2 spike protein epitopes (FIAGLIAIV, LITGRLQSL, YLQPRTFLL, RLQSLQTYV).30 , 31 Spike-specific CD8+ T cell frequency (staining for ≥1 spike-specific epitope) was evaluated out of total memory CD8+ T cells (gated on CD3+CD4−CD8+ cells, excluding naïve CCR7+CD45RA+ T cells). Positive spike-specific CD8+ T cell response threshold was ≥0.03% (above HLA-A∗02-negative HC staining background). 2.3.2 Immunosequencing of SARS-CoV-2–associated T cell repertoires SARS-CoV-2–associated T cell repertoires were assessed via TCR sequencing in n = 65 KTRs and n = 19 HCs using the Adaptive Biotechnologies immunoSEQ Assay platform.32 , 33 PBMCs were isolated on days 0 and 30, frozen, and sent to Adaptive for high-resolution immunosequencing. The abundance of each unique TCRβ CDR3 sequence was quantified (defining the overall TCR clonal repertoire) before and after vaccination. The set of detected TCR clones was then compared against a library of ∼5,000 “high-confidence” public clones recognizing epitopes across the SARS-CoV-2 genome found to be enriched in COVID-19 convalescent patient samples (vs prepandemic controls) using multiplex identification of antigen-specific TCRs32 to reduce potential cross-reactive TCRs.33 The same machine-learning algorithm as the clinically available FDA T-Detect COVID Test (https://www.fda.gov/media/146481/download) was applied to provide a binary classifier (T-MAP COVID), reporting whether TCR repertoires were SARS-CoV-2–reactive: ie, T-MAP “positive,” “negative,” or “indeterminate” (insufficient TCR sequences to permit classification). TCR repertoire components were then individually evaluated: (1) breadth, the proportion of unique clones reacting to SARS-CoV-2 out of all unique TCRs (ie, diversity of SARS-CoV-2–reactive clones) and (2) depth, the proportion of all productive TCR templates that react to SARS-CoV-2 of all detected TCRs (ie, total number of SARS-CoV-2–reactive clones). These metrics were reported for CD4+ and CD8+ compartments against both spike-specific and nonspike cognate regions (eg, nucleocapsid) identified via multiplex identification of antigen-specific TCRs. 2.4 Statistical analysis KTR characteristics were compared between (1) anti-RBDNEG and anti-RBDLO and (2) anti-RBDNEG KTRs who remained seronegative and anti-RBDNEG KTRs who seroconverted on day 30, using Fisher exact and Wilcoxon rank-sum testing (categorical and continuous variables, respectively). Day 30 anti-RBD, neutralization, and T cell responses were compared between KTRs and HCs using Wilcoxon rank-sum testing. Anti-RBD half-life for KTRs with day 30 anti-RBD ≥500 was estimated via exponential decay modeling. Participants who developed incident COVID-19 (for all outcomes; triangles, Fig. 1 A) or received monoclonal antibody (mAb) (for humoral outcomes; open circles, Fig. 1A) were excluded from immunogenicity analyses but included in data visualization.Figure 1 (A) Anti-receptor binding domain (anti-RBD) titers in KTRs following a third mRNA vaccine dose, stratified by day 0 anti-RBD level. Blue trajectories represent anti-RBDNEG (n = 39) and yellow trajectories represent anti-RBDLO low-titer (n = 42). Anti-RBD titers are represented in units/mL on the logarithmic scale. Triangles represent participants who developed incident COVID-19 (n = 4), and circles represent participants receiving monoclonal antibody (mAb) (n = 1). Squares represent participants with a history of COVID-19 prior to third vaccination. (B) Comparison of anti-receptor binding domain (anti-RBD) titers between KTRs and HCs before and 30 days after a third mRNA vaccine dose. Anti-RBD titers are represented in units/mL on the logarithmic scale. Triangles represent participants who developed incident COVID-19 (n = 1), and circles represent participants receiving monoclonal antibody (mAb) (n = 1) before day 30. Squares (n = 6) represent participants with a history of COVID-19 prior to third vaccination. HC, healthy control; KTR, kidney transplant recipient; RBD, receptor binding domain. Figure 1 Associations with day 30 anti-RBD were assessed using (1) Poisson regression with robust variance estimator (RVE) for anti-RBD >2500 U/mL (potential threshold for Omicron BA.1 neutralization7 , 34) and (2) negative binomial regression with RVE for continuous anti-RBD. Based on published literature,1 multivariable models included high-dose mycophenolate (MMF; >1000 mg mycophenolate mofetil or >720 mg mycophenolic acid, daily), transplant vintage, and post hoc inclusion of day 30 CD4+ TCR breadth given mechanistic plausibility and exploratory data analysis. The proportions of participants with SARS-CoV-2–reactive repertoires ([+]T-MAP) on day 0 and day 30 was compared used McNemar’s and Fisher exact testing. Associations of baseline characteristics with day 30 (+)T-MAP were assessed using Poisson regression with RVE; indeterminate repertoires were excluded from comparative analyses. Differences in TCR breadth and depth from day 0 to day 30 were analyzed by Wilcoxon rank-sum and matched-pairs signed-rank test as appropriate. Associations between day 30 spike-specific TCR expansion and anti-RBD were assessed by linear fit and Spearman rank. Participants with undetectable SARS-CoV-2 TCRs were assigned values of 1 × 10-6 for analytical and visualization purposes and excluded on sensitivity analysis. Among KTRs, day 30 response patterns were assessed across 2 binary dimensions, (+)/(-)anti-RBD and (+)/(-)T-MAP, with comparison of participant characteristics. Modeling outputs are presented in the style of Louis and Zeger35, lower 95% CIPoint Estimateupper 95% CI. Two-sided α < 0.05 denotes statistical significance. Analyses were performed using Stata/SE_17.0. 3 Results 3.1 Study population After screening, n = 81 KTRs (n = 39 anti-RBDNEG, n = 42 anti-RBDLO) were administered a third homologous vaccine dose (22 Moderna mRNA-1273, 59 Pfizer-BNT162b2) at median (interquartile range [IQR]) 167 (149-177) days after dose 2. Demographics, laboratory, and transplant factors were similar between anti-RBDNEG and anti-RBDLO (Table 1 ).Table 1 Demographic and transplant characteristics of KTRs, by day 0 anti-RBD level. Table 1 Total (N = 81) anti-RBDNEG (N = 39) anti-RBDLO (N = 42) P Demographics Age (y), median (IQR) 66 (57, 73) 65 (56, 73) 66 (57, 74) .99 Female sex, no. (%) 27 (33) 17 (44) 10 (24) .10 Race, no. (%) .75 White 49 (60) 22 (56) 27 (64) Black/African American 24 (30) 12 (31) 12 (29) Asian 4 (5) 2 (5) 2 (5) Other 4 (5) 3 (8) 1 (2) Hispanic/Latino ethnicity, no. (%) 2 (2) 2 (5) 0 (0) .23 BMI (kg/m2), median (IQR) 26.2 (23.4, 31.2) 27.5 (23.2, 32.0) 25.8 (23.4, 31.1) .53 Medical comorbidities Diabetes, no. (%) 27 (33) 13 (33) 14 (33) >.99 HCV infection, no. (%) 5 (6) 1 (3) 4 (10) .36 Lung disease, no. (%) 25 (31) 14 (36) 11 (26) .47 Cardiovascular disease, no. (%) 80 (99) 38 (97) 42 (100) .48 Autoimmune disease, no. (%) 12 (15) 7 (18) 5 (12) .54 Transplant history and immunosuppression Years since transplant, median (IQR) 5.4 (2.1, 10.5) 5.0 (2.0, 9.2) 5.7 (3.2, 10.9) .23 Indication for most recent kidney transplantation, no. (%) Diabetes 13 (16) 6 (15) 7 (17) >.99 Hypertension 28 (35) 16 (41) 12 (29) .25 FSGS 6 (7) 5 (13) 1 (2) .10 Cystic kidney disease 11 (14) 3 (8) 8 (19) .20 Living donor, no. (%) 35 (43) 14 (36) 21 (50) .26 DSA positive at baseline, no. (%) (n = 79) 14 (17) 7 (18) 7 (18)a >.99 Baseline Immunosuppressant, no. (%) Mycophenolate mofetil 56 (69) 27 (69) 29 (69) >.99 Total daily dose (mg), median (IQR) 1000 (500, 1000) 1000 (500, 1000) 1000 (500, 1000) .95 Mycophenolic acid 8 (10) 5 (13) 3 (7) .47 Total daily dose (mg), median (IQR) 720 (540, 900) 810 (720, 1440) 540 (270, 810) .16 High-dose mycophenolate 14 (17) 9 (23) 5 (12) .37 Prednisone 75 (93) 36 (92) 39 (93) >.99 Total daily dose (mg), median (IQR) 5 (5, 5) 5 (5, 5) 5 (5, 5) .94 Tacrolimus 75 (93) 38 (97) 37 (88) .20 Cyclosporine 4 (5) 1 (3) 3 (7) .62 Triple IS, no. (%)b 58 (72) 29 (74) 29 (69) .63 COVID-19 and vaccination history Prior SARS-CoV-2 infectionc, no. (%) 4 (5) 3 (8) 1 (2) .35 Days between second and third dose, median (IQR) 167 (149, 177) 159 (141, 174) 169.5 (152, 183) .10 Vaccine manufacturer, no. (%) .46 Pfizer-BioNTech (BNT162b2) 59 (73) 30 (77) 29 (69) Moderna (mRNA-1273) 22 (27) 9 (23) 13 (31) Laboratory results Creatinine (mg/dL), median (IQR) Day 0 (Baseline) 1.2 (1, 1.5) 1.2 (1, 1.5) 1.2 (1.1, 1.5) .59 Day 30 1.2 (1, 1.5) 1.3 (1, 1.5) 1.2 (1.1, 1.5) .78 Estimated GFR (ml/min/1.73m2), median (IQR) Day 0 58 (46, 73) 57 (49, 72) 59.5 (46, 74) .91 Day 30 59 (46, 72) 55 (46, 72) 60.5 (45, 73) .82 Baseline ALC (K/cu mm), median (IQR) 1.01 (0.69, 1.47) 1.01 (0.66, 1.55) 1.00 (0.7, 1.37) .82 Baseline Total IgG (mg/dL), median (IQR) 859 (737, 1057) 863 (755, 1008) 834 (732, 1086) .89 Baseline CD4+ T cell count, median (IQR)d 172 (114, 225) 183 (111, 228) 171 (114, 220) .56 Recipient CMV IgG positive, no. (%) (n=72) 38 (53) 18 (53) 20 (51) >.99 ALC, absolute lymphocyte count; BMI, body mass index; CMV, cytomegalovirus; DSA, donor-specific antibody; FSGS, focal segmental glomerulosclerosis; GFR, glomerular filtration rate; IgG, immunoglobulin G; HCV, hepatitis C virus; IQR, interquartile range; IS, immunosuppressant. Continuous outcomes compared by Wilcoxon rank-sum testing and categorical variables were compared by Fisher exact testing. a Donor HLA typing unavailable for n = 1 participant and day 0 recipient DSA screening missing for n = 1 participant. b Any combination of 3 immunosuppressants at day 0 (calcineurin inhibitor, antimetabolite, corticosteroid). c By positive prior molecular testing or reactive anti-nucleocapsid antibody at enrollment. d T cell subtyping performed on n = 34 KTRs (16 anti-RBDNEG, 18anti-RBDLO) The HC cohort included n = 19 persons, median (IQR) age 29 (28-35) years, all of whom received third homologous monovalent BNT162b2 vaccination median (IQR) 269 (261-277) days after dose 2 (Supplement). Two showed evidence of prior COVID-19 by day 0 anti-nucleocapsid testing. 3.2 Antibody and neutralization 3.2.1 Binding antibody responses Among 79 KTRs (excluding n = 2 who developed COVID-19 or received mAb), median (IQR) day 30 anti-RBD titer was 561 (8.9-2567.5) U/mL (Fig. 1A), as compared with 13 170 (9915-28 755) U/mL in HCs (23-fold lower, P < .001; Fig. 1B). Day 30 median (IQR) anti-RBD was >270-fold higher in anti-RBDLO vs anti-RBDNEG KTRs: 2438.5 (740.3-5352.5)U/mL vs 9.0 (<0.4-147)U/mL (P < .001), respectively. In KTRs, anti-RBD decreased 38% by day 90, with an estimated half-life of 71 days. Among anti-RBDNEG KTRs, 17/39 (44%) remained seronegative on day 30 (vs 0 HCs). Demographic, immunosuppressant, and vaccination factors were similar among KTRs who did vs did not seroconvert (Supplementary Table S1). Persistently seronegative KTRs demonstrated lower median (IQR) IgG levels (779 [714-881] vs 965 [846-1128] mg/dL, P = .012) and absolute lymphocyte counts (0.70 [0.59-1.36] vs 1.16 [0.93-1.57] K/mm3, P = .035), with a trend toward lower CD4+ T cell counts (120 [98-146] vs 223 [147-258] cells/μL, P = .07) (Supplementary Table S1). High-level anti-RBD (>2500 U/mL, n = 20 [25%] KTRs vs n = 19 [100%] HCs) was associated with older transplant vintage (Ratio = 1.171.351.55 [per 5 years], P < .001) (Table 2 ) in KTRs, but not participant age or mRNA-1273 (vs BNT162b2). Anti-RBD was lower among KTRs taking high-dose MMF (Ratio = 0.040.241.70, P = .15), without reaching statistical significance.Table 2 Associations between clinical factors and day 30 anti-RBD level. Table 2Factor >2500 U/mL ratio P (crude) Continuous titer ratio P (crude) Continuous titer ratio (adjusted) P (adjusted) Age (per 10 y) 0.70 0.95 1.30 .75 0.72 0.91 1.18 .49 Female sex 0.50 1.102.43 .82 0.48 1.082.42 .85 mRNA-1273 vaccine 0.49 1.112.53 .80 0.43 0.831.62 .59 Mycophenolate (n = 78) 0.27 0.601.32 .21 0.27 0.601.32 .21 High-dose mycophenolate 0.04 0.24 1.70 .15 0.08 0.37 1.67 .20 0.020.060.18 <.001 Triple immunosuppression 0.27 0.58 1.23 .15 0.32 0.64 1.26 .19 Transplant vintage (per 5 y) 1.171.351.55 <.001 0.95 1.15 1.38 .15 0.79 0.95 1.15 .61 Lymphocyte <1000 cell/μL 0.85 1.904.29 .12 0.91 1.78 3.49 .09 Absolute CD4+ count (per 100) (n = 33) 0.59 1.06 1.92 .85 0.75 0.98 1.27 .86 Day 0 CD4+ breadth (per 10-fold) (n = 63) 0.92 2.57 7.23 .07 0.65 1.50 3.47 .34 Positive day 0 T-MAP (n = 52) 1.343.197.64 .009 0.70 1.61 3.74 .27 Day 30 CD4+ breadth (per 10-fold) (n = 63) 0.69 1.69 4.14 .25 0.80 1.58 3.10 .19 1.052.054.02 .37 Positive day 30 T-MAP (n = 55) 1.053.4611.34 .041 1.383.237.55 .007 Crude univariable associations are presented for the outcomes of high-titer anti-RBD response (>2500 U/mL) and continuous anti-RBD level at day 30. An adjusted multivariable model for continuous anti-RBD response is also presented (n = 63). Bolded values represent statistical significance at the P < .05 level. Note: All analyses excluded n = 1 participant with incident COVID-19 and n = 1 participant who received monoclonal antibody; the mycophenolate univariable analysis excluded n = 1 additional participant with inconsistent medication use during follow-up (was not prescribed high-dose mycophenolate). Sample sizes for all other univariable models are indicated next to the variable name. 3.2.2 Neutralization Among 79 KTRs, the proportion demonstrating ancestral strain neutralization (≥25% ACE2i) increased from 0% (n = 0) to 34% by day 30 (n = 27; 24 anti-RBDLO vs 3 anti-RBDNEG) (McNemar’s P < .001). No KTR showed Omicron subvariant neutralization on day 0 and a minimal increase by day 30: 2 (3%), 0 (0%), 0 (0%), 4 (5%) neutralized BA.1, BA.2, BA.2.75, and BA.5 spike, respectively (all anti-RBDLO; McNemar’s P > .05 all subvariants; Fig. 2 ). Of the KTRs showing BA.5 neutralization at day 30, 0/4 and 2/4 showed BQ.1.1 and XBB.1 neutralization, respectively. Confirmatory live virus testing of KTR samples on day 30 detected ancestral nAb > 1:20 in 33 (42%, 29 anti-RBDLO, median NT50 1:80), and BA.1 nAb > 1:20 in 6 (8%, all anti-RBDLO, median NT50 1:40 [low-level]) (Supplementary Fig. S2).Figure 2 Neutralizing capacity against SARS-CoV-2 variants before and 30 days after a third mRNA dose in KTRs and HCs. The Y axis represents percent ACE2 inhibition, ranging 0% to 100% with ≥25% consistent with neutralizing inhibition (dashed orange line). Triangles denote participants with incident COVID-19 (n = 4) and open circles denote participants receiving mAb (n = 1). Squares indicate participants with a prior history of COVID-19 (n = 4 KTRs, n = 2 HCs). HC, healthy control; KTR, kidney transplant recipient. Figure 2 Among n = 19 HCs, the proportion demonstrating ancestral strain neutralization increased from 16% (n = 3) to 100% (n = 19) by day 30 (McNemar’s P < .001). No HC demonstrated Omicron subvariant neutralization on day 0, with a significant increase by day 30: 8 (42%), 9 (47%), and 13 (68%) neutralized BA.2, BA.2.75, and BA.5 spike by day 30 (McNemar’s P < .01, all subvariants). Of HCs with BA.5 neutralization on day 30, 11/13 and 12/13 showed BQ.1.1 and XBB.1 neutralization, respectively. For each variant tested, median %ACE2i and proportion ≥25% were significantly higher on day 30 in HCs than in KTRs (P < .01 by rank-sum and Fisher exact testing, respectively, except for median BA.2 %ACE2i [P = .45]). History of prior COVID-19 did not appear associated with augmented neutralization in either group on day 30. Interestingly, the highest Omicron sublineage neutralization was observed in a KTR with breakthrough infection (see Breakthrough infections, Section 3.5). 3.3 Cellular analyses 3.3.1 SARS-CoV-2 spike-specific CD8+ T cell response (pentamer staining) Among HLA-A∗02 KTRs, 0/33 (0%) showed spike-specific CD8+ T cell response on day 0, increasing to 3/32 (9%) by day 30 (n = 2 anti-RBDLO) (McNemar’s P = .25, Fig. 3 ). In contrast, 7/9 (78%) HCs showed spike-specific CD8+ response on both day 0 and day 30. Median (IQR) CD8+% was 4.5-fold lower in KTRs than HCs on day 0 (0.0082% [0.0046-0.0098] vs 0.037% [0.036-0.072], P < .001) and 9.7-fold lower on day 30 (0.0079% [0.0031-0.014] vs 0.077% [0.031-0.22], P < .001). The change in CD8+% among KTRs from day 0 to day 30 was not significant (P = .28), although it trended toward an increase in HCs (P = .07). Day 30 CD8+ T cell response did not correlate well with anti-RBD level (KTR r s = +0.17, HC r s =-0.23, Supplementary Fig. S4), although all KTRs with positive CD8+% had positive anti-RBD (2 measurements >2500 U/mL). Both HCs with prior COVID-19 showed positive CD8+ response at day 0 and day 30, whereas the 1 KTR with prior COVID-19 showed a negative response at both time points.Figure 3 SARS-CoV-2 spike-specific CD8+ memory T cell responses before and after a third mRNA vaccine dose in KTRs and HCs. Flow cytometric data (epitope staining) are presented for HLA-A∗02 participants. The dashed orange line represents background staining threshold (<0.03%). Triangles denote participants who developed COVID-19 (n = 1) and squares indicate participants with prior history of COVID-19 (n = 3). HC, healthy control; KTR, kidney transplant recipient. Figure 3 3.3.2 SARS-CoV-2 T cell repertoire analysis (TCR sequencing) SARS-CoV-2–reactive TCR repertoires ([+]T-MAP) were detected in 10/52 (19%) KTRs on day 0, increasing to 27/52 (52%) by day 30 (McNemar’s P < .001), after excluding participants with indeterminate repertoires (n = 12). Day 30 reactive repertoires were ∼2-fold more frequent in anti-RBDLO 18/28 (64%) vs anti-RBDNEG 9/24 (38%), P = .09. In contrast, among HCs, 6/19 (32%) and 14/19 (74%) had (+)T-MAP on day 0 and day 30, respectively (McNemar’s P < .001, Fisher exact P = .11 vs day 30 KTR%). Among KTRs, demographics factors were similar between (+) and (-)T-MAP on day 30, apart from older transplant vintage in (+)T-MAP (median [IQR] 8.1 [4.9-13.3] vs 4.9 [2.2-8.8] years, P = .04, Supplementary Table S4). No demographic or transplant factors were significantly associated with (+)T-MAP on day 30, apart from anti-RBDNEG status (Ratio = 0.300.551.00; P = .048) (Supplementary Table S3). Among KTRs, total spike-specific TCR breadth (“unique clones”) increased 2-fold from 1.90 × 10-5 to 3.90 × 10-5 (P < .001) and depth (“total clones”) 2.9-fold from 6.9 × 10-6 to 1.99 × 10-5 (P < .001) between day 0 and day 30 (Supplementary Table S5, Supplementary Fig. S6); these measures were highly correlated (r > 0.9, Supplementary Fig. S5). TCR response was more prominent in the CD4+ compartment; spike-specific CD4+ breadth increased 1.47 × 10-5 to 2.62 × 10-5; P < .001, whereas spike-specific CD8+ breadth expansion was more limited (<1.0 × 10-6 to 1.89 × 10-6; P = .002). Notably, all dimensions of the spike-specific TCR repertoire at day 30 were 2- to 5-fold greater in anti-RBDLO vs anti-RBDNEG participants, eg, spike-specific CD4+ breadth of 3.67 × 10-5 vs 1.39 × 10-5 (P = .026). As expected, there was no significant increase in nonspike TCRs between day 0 and day 30 (median breadth 2.12 × 10-5 to 2.17 × 10-5, P = .37; median depth 9.68 × 10-6 to 9.55 × 10-6, P = .25; [Supplementary Table S5, Supplementary Fig. S6]). Similar repertoire changes were observed in HCs between day 0 and day 30, with significant expansion of spike-specific TCRs, particularly CD4+ (P < .001 for breadth, depth), without significant nonspike TCR expansion (P > .05 for breadth, depth). Interestingly, there was no difference in day 30 spike-specific CD4+ measures between HCs and KTRs (CD4+ breadth 2.52 × 10-5 vs 2.62 × 10-5, P = .63; Supplementary Table S5). Spike-specific CD8+ measures, however, were all significantly greater in HCs vs KTRs, particularly CD8+ depth (7.6-fold higher on day 30, P = .001). Day 30 spike-specific CD8+ TCR breadth (r s = 0.44, P = .01) and depth (r s = 0.53, P = .001) positively correlated with spike-specific CD8+% by MHC-pentamer staining, though this relationship was primarily driven by HCs (Supplementary Fig. S7). Multivariable modeling of day 30 anti-RBD level in KTRs incorporating TCR measures revealed a positive association of day 30 spike-specific CD4+ T cell breadth (aRatio = 1.052.054.02 [per 1 log], P = .037) and a highly significant negative association of high-dose MMF (aRatio=0.020.060.18, P < .001) after accounting for transplant vintage. On sensitivity analysis excluding participants with 0 TCR breadth, the point estimate for high-dose MMF was similar (aRatio = 0.030.070.16, P < .001), whereas CD4+ breadth point estimate increased (aRatio = 5.3111.5124.92 [per 1 log], P < .001). 3.4 Response patterns after full vaccination: humoral and cellular correlations 3.4.1 Categorization of anti-RBD and T cell responses Response patterns on day 30 were characterized using dichotomous categories of (+)/(-)anti-RBD and (+)/(-)T-MAP (n = 55 KTRs; excluding n = 8 with indeterminate T-MAP, n = 1 with incident COVID-19, and n = 1 with incident mAb). Global negative response (-)anti-RBD/(-)T-MAP was seen in 4 (7%) participants vs global positive response (+)anti-RBD/(+)T-MAP in 22 (40%). Discordant responses were seen in 29 (53%) participants: 24 (44%) with (+)anti-RBD/(-)T-MAP and 5 (9%) with (-)anti-RBD/(+)T-MAP (Supplementary Table S6). High-dose MMF was used in 3/4 (75%) with global negative responses, as compared with 20% (range 13% to 27%) of participants with other patterns (Supplementary Table S6, Fisher exact P = .037). Age and other demographic features were similar across response patterns apart from oldest transplant vintage in persons with (-)anti-RBD/(+)T-MAP (P = .046). As all HCs showed (+)anti-RBD at day 30 (74% global positive response). 3.4.2 Association of TCR repertoire expansion and anti-RBD response Among KTRs with (+)anti-RBD on day 30, there was a positive correlation between spike-specific CD4+ TCR breadth and anti-RBD on day 30 (Fig. 4 , r s = 0.34, P = .02); a similar association was observed with spike-specific CD4+ T cell depth (Fig. 4, r s = 0.34, P = .02). Correlations with CD4+ breadth (r s = 0.41, P = .007) and depth (rs = 0.41, P = .008) were similar after excluding KTRs with negative TCR values. In contrast, among KTRs with (-)anti-RBD on day 30, spike-specific CD4+ TCR responses varied widely. Additionally, spike-specific CD4+ TCR breadth on day 30 was similar between anti-RBDNEG KTRs who did vs those who did not seroconvert (P = .11, data not shown). Correlations between day 30 anti-RBD level and CD8+ TCR breadth (P = .06) or depth (P = .05) were not statistically significant (Fig. 4).Figure 4 Response patterns following third mRNA vaccine doses: correlation of SARS-CoV-2 antibody and T cell responses. Scatterplot of anti-receptor binding domain (RBD) level and dimensions of SARS-CoV-2 T cell receptor expansion (spike-specific CD4+ and CD8+ breadth and depth) on the logarithmic scale at day 30 post vaccination among kidney transplant recipients (A, n = 55) and healthy controls (B, n = 19). Data points are colorized by response pattern, (+)/(-) anti- RBD and (+)/(-)T-MAP (SARS-CoV-2-reactive T cell repertoire). Trend lines visualize correlation between vaccine responses in participants with detectable signatures (i.e., (+)anti-RBD and categorizable T cell receptor repertoire). Figure 4 KTRs with global positive responses at day 30 had median (IQR) anti-RBD 1499 (118-5225) U/mL, including 10 (45%) with anti-RBD >2500 U/mL, and 2 (9%) demonstrated Omicron BA.5 neutralization. In contrast, KTRs with (+)anti-RBD/(-)T-MAP (discordant pattern) demonstrated median (IQR) anti-RBD 441 (23-1124) U/mL (P = .03 vs global positive), including only 3 (10%) with anti-RBD >2500U/mL (0 showed BA.5 neutralization). Overall, anti-RBD >2500U/mL was achieved in 37% (+)T-MAP vs 11% (-)T-MAP KTRs (P = .029). In contrast, among HCs, there was no significant correlation between CD4+ TCR measures and anti-RBD (breadth r s = 0.24 [P = .3]; depth r s = 0.20 [P = .4]). Additionally, there was no significant difference in anti-RBD level if (+)T-MAP vs (-)T-MAP (median 13 976 U/mL vs 12 885 U/mL, P = .7). 3.5 Breakthrough infections There were 13 SARS-CoV-2 infections among KTRs (16%) at median 99 days (range 13-141) after third vaccination (Table 3 ). Four KTRs were infected before day 90, during the Delta wave, whereas most (88%) late infections occurred during the Omicron BA.1 wave. Nearly all cases (92%) were symptomatic; 2 (15%) required hospitalization without intensive care. Median (IQR) anti-RBD level preinfection was 91 (16-429) U/mL, including 3 (23%) with negative titers; none displayed preinfection BA.1 neutralization, although 2 showed Delta neutralization (1 had received mAb).Table 3 Clinical and immunological characteristics of 13 breakthrough SARS-CoV-2 infections. Table 3Age; y (decade) Sex Days from dose 3 to infectiona Variant waveb Day 0 anti-RBD level Day 30 anti-RBD level Preinfection anti-RBD Pre- infection Delta %ACE2i Pre- infection BA.1 %ACE2i Preinfection T cell reactivity mAb received for infection Days from infection to sampling Postinfection anti-RBD Postinfection Delta %ACE2i Postinfection BA.1 %ACE2i COVID-19 severity 50-59 M 13 Delta (Sept 2021) 21.6 21.6 21.6 9.0% 1.3% T-MAP(-) CD8(-) None 18 163 120 >99% 98.1% Mild: symptomatic, outpatient 30-39 M 74 Delta (Nov 2021) 2.7 1145 1145 11.8% 3.4% T-MAP(+) Casirivimab/ imdevimab 15 32 400 >99% 22.0% Mild: symptomatic, outpatient 40-49 F 74 Delta (Nov 2021) <0.8 666 666 33.3% 4.8% CD8(-) None 22 12 758 72.9% 19.7% Mild: symptomatic, outpatient 50-59 M 76 Delta (Nov 2021) 3.8 73.1 73.1 8.8% 6.8% T-MAP(+) Casirivimab/imdevimab 16 46 880 >99% 72.0% Moderate: hospitalization, oxygen by nasal cannula 70-79 M 95 BA.1 (Dec 2021) 1.9 2310 1484 13.5% 3.0% T-MAP(-) CD8(-) None 86 29 820 98.3% 71.5% Mild: symptomatic, outpatient 60-69 M 98 BA.1 (Dec 2021) <0.8 301 123 4.5% 5.7% CD8(-) Sotrovimab 77 10 580 73.6% 11.9% Mild: symptomatic, outpatient 70-79 M 98 Delta (Nov 2021) <0.8 <0.8 <0.8 4.5% 8.1% .. Bamlanivimab/etesevimab 86 3400 90.5% 0% Mild: symptomatic, outpatient 40-49 F 99 BA.1 (Dec 2021) <0.8 <0.8 <0.8 4.5% 0.0% .. None .. .. .. .. Moderate: hospitalization, oxygen by nasal cannula 60-69 M 122 BA.1 (Jan 2022) 2.5 2153 1079 6.3% 2.2% .. Sotrovimab 51 19 550 90.4% 62.9% Mild: symptomatic, outpatient 50-59 F 126 BA.1 (Dec 2021) 4.7 6650c 821c 98.0%c 0.0%c T-MAP(+) Sotrovimab 66 10 910 .. .. Mild: symptomatic, outpatient 60-69 F 127 BA.1 (Jan 2022) <0.8 <0.8 <0.8 6.4% 9.0% T-MAP(+) Sotrovimab 61 6740 39.3% 12.5% Mild: symptomatic, outpatient 70-79 M 128 BA.1 (Dec 2021) <0.8 52.6 23.7 9.6% 6.6% CD8(-) None 58 44 617d >99%d >99%d Mild: asymptomatic, outpatient 50-59 M 141 BA.1 (Jan 2022) 10.1 838 110 6.6% 2.7% T-MAP(-) CD8(-) Sotrovimab 46 12 475 53.1% 15.2% Mild: symptomatic, outpatient Note: Breakthrough infections identified via positive SARS-CoV-2 test or anti-nucleocapsid antibody seroconversion. Preinfection measures (anti-RBD, surrogate neutralization [%ACE2 inhibition, ≥25% consistent with neutralizing capacity], T cell reactivity [T-MAPTM TCRseq classifier and/or spike-specific CD8%]) represent last available timepoint before confirmed infection. Postinfection measures represent first timepoint following breakthrough. COVID-19 treatment was at the discretion of the primary transplant team. a Date of PCR confirmation available for 12 participants, date of symptom onset used for remaining 1 participant. b Delta wave defined as August 1 to December 1, 2021. Omicron wave (BA.1) defined as December 24, 2021 to February 1, 2022; there were no infections during period of Delta and Omicron co-circulation December 1 to December 23, 2021). Confirmatory sequencing was not performed. c Received prior casirivimab/imdevimab on day 16 post vaccination (active against the Delta variant). d Received fourth vaccine dose (monovalent mRNA booster) before postinfection sampling. Postinfection anti-RBD and neutralization were augmented in 4 KTRs infected before day 90 (triangles, Figure 1, Figure 2), above nearly all other participants (2 also received mAb). Two participants with breakthrough were the only KTRs to demonstrate high-level BA.1 nAb on day 90 (Supplementary Fig. 2), including 1 with high-level neutralization against all Omicron subvariants including BQ.1.1 and XBB.1 (did not receive mAb). Neutralizing capacity after BA.1 infections was variable, including 3/8 KTRs showing ACE2i <25% after infection (all received mAb). Of 10 participants with preinfection SARS-CoV-2 T cell data, 6/6 (100%) had negative CD8+ response by MHC-pentamer staining and 3/7 (43%) had (-)T-MAP; 1 participant with (+)T-MAP preinfection required hospitalization. 4 Discussion In this trial designed to systematically characterize immunogenicity of third mRNA vaccines in poor anti-RBD responders, we demonstrated substantial SARS-CoV-2–specific immune deficits despite full vaccination in KTRs. The findings confirm the major impact of preceding anti-RBD serostatus on subsequent responses, with nearly half anti-RBDNEG failing to seroconvert. Although some participants with anti-RBDLO attained high anti-RBD titers, only 5% showed Omicron BA.5 neutralization (none neutralized BQ.1.1). SARS-CoV-2–specific CD4+ responses measured by TCR sequencing improved with vaccination, dovetailing with highest-level anti-RBD, to define a global positive response pattern in 40% KTRs. Yet, even in these participants, SARS-CoV-2–specific CD8+ responses by MHC-pentamer staining and TCR sequencing were limited; <10% KTRs showed spike-specific CD8+ staining, and CD8+ TCR depth was >7-fold lower vs HCs. Breakthrough infections were common, predominately occurring among KTRs with lower anti-RBD and poor neutralizing capacity, without clear relation to measures of T cell reactivity. This trial further supports the negative association of high-dose MMF with humoral vaccine response,6 , 10 , 11 which strengthened after accounting for CD4+ TCR breadth and transplant vintage, suggesting heavy lymphocyte impairments. Given suboptimal immune responses and neutralization in many KTRs following repeated mRNA vaccination,8 , 13 , 36 exploring perivaccination MMF reduction among low alloimmune risk KTRs is of great interest, having shown safety and potentially augmented immunogenicity in small observational studies37 and a clinical trial38; a multicenter CPAT trial (NCT05077254) is currently underway. Although persistent anti-RBD seronegativity was common, there was no clear association with standard clinical or transplant characteristics, and many showed equivalent CD4+ expansion as anti-RBD responders. Remarkably, CD4+ expansion was similar between KTRs and HCs, despite striking differences in anti-RBD and neutralization. This suggests spike-specific CD4+ T cell reactivity as necessary but not sufficient for high-level anti-RBD responses in KTRs. Coupled with findings of lower lymphocyte counts and IgG levels in persistently seronegative participants, these investigations suggest B cell dysfunction and/or qualitative T cell defect as contributors to poor antibody response.3 This may include metabolic dysfunction related to MMF,39 ineffective T follicular helper cell production, and/or costimulation.6 , 19 Investigating the state and interactions of B and T cells in KTRs with poor humoral response despite T cell reactivity is a potential avenue to delineate mechanisms of vaccine nonresponse and target augmentation strategies. Breakthrough infections were common, predominantly among those with poor plasma neutralizing capacity. In the era of active mAbs, there was no critical illness, yet with loss of activity against newer Omicron sublineages, outcomes may not be as favorable. Delta variant infection elicited impressive humoral responses, including 1 KTR with cross-variant neutralization against BQ.1.1 and XBB.1, whereas immunogenicity following BA.1 infection was more variable, potentially related to high antigenic distance from the vaccine strain.40 Notably, several participants showed SARS-CoV-2 T cell reactivity prior to infection, including 1 participant who required hospitalization, suggesting cellular markers may not correlate as strongly with protection against COVID-19. Given poor CD8+ response and lack of correlation with anti-RBD, it is challenging to presume strong T cell immunoprotection in the absence of high-level humoral response, although this remains a critical scientific frontier. Strengths of this trial include explicit focus on high-risk KTRs, using clinically available biomarkers and studying associations with neutralizing measures and deeper evaluation of SARS-CoV-2–associated T cell compartments. Additionally, breakthrough ascertainment was robust, leveraging serial assessment of pre- and postinfection immune responses. Limitations include smaller sample size, resulting from strict inclusion criteria and contemporaneous availability of third vaccines in the community, reducing power to detect immunological associations. Additionally, due to HLA and PBMC restrictions, T cell analyses were not performed on all participants. Although the broader SARS-CoV-2–reactive T cell repertoire was interrogated, focus was upon public/immunoprevalent epitopes, and functional capacity and metabolic state of cells were not explicitly evaluated. Furthermore, although HCs provided critical framing of poor multifactorial KTR responses, cohorts were not age- and comorbidity-matched, which may explain some variance in immunogenicity. Thus, the findings are hypothesis-generating and should be considered alongside other investigations into the varied cellular immunoprotection following vaccination and infection19 , 41 and their real-world implications for KTRs. In summary, a third mRNA vaccine dose augmented anti-RBD in KTRs with prior detectable antibody after a 2-dose series, albeit to levels far below that of HCs; ≤5% demonstrated contemporary Omicron sublineage neutralization. Spike-reactive CD4+ T cell repertoires after vaccination correlated with highest-level anti-RBD response in KTRs yet did not fully discriminate humoral responders. High-dose MMF significantly impaired anti-RBD response, potentially via B cell dysfunction and/or ineffective CD4+ help. Paucity of neutralization and CD8+ response suggests vulnerability to infection in the majority of these high-risk KTRs in the Omicron era. Alternative vaccination strategies are needed to enhance immunoprotection in KTRs, particularly those with negative anti-RBD, including targeted immunosuppression reduction37 , 42 or exploration of alternative platforms including adjuvanted vaccines. Funding This work was supported by the National Institutes of Health (NIH) to CMD and DLS (U01 AI138897). Additional research support was provided by the NIH to CMD and DLS (U01 AI134591), WAW (K23 AI157893) AART (R01 AI20938), AHK (K08 AI156021), ACJ (T32 AI070081), CPL (U19 AI051731, R01 MD011682, R01 AI126322, U01 AI138909), the National Cancer Institute to ALC and SLK (U54 CA260491), the Johns Hopkins University Center for AIDS Research to WAW (P30 AI094189), the James O. Robbins Fellowship to ACJ, and the James M. Cox Foundation and the Carlos and Marguerite Mason Trust to CPL. Disclosure The funder of the study (US NIH) was not involved in patient recruitment, data collection, analysis, or visualization; the funder was involved in protocol design, data interpretation, manuscript writing, and the decision to submit for publication as per cooperative agreement. No agencies provided payment for the writing of this report. All authors had access to the full data in the study and accept responsibility for the decision to submit for publication. The authors of this manuscript have conflicts of interest to disclose as described by the American Journal of Transplantation. Outside of the submitted work, the following authors declare: W. Werbel: AstraZeneca (consulting), Novavax (advisory board), GlobalData (consulting); A. Karaba: Roche (consulting); R. Avery: Aicuris, Astellas, Chimerix, Merck, Oxford Immunotec, Qiagen, Regeneron, Takeda/Shire (research support to institution); M. Bettinotti: CareDx, One Lambda Thermofisher (scientific advisory board); N. Rouphael: ICON, EMMES, MICRON, Krog (consulting), ARLG, TMRC, CDC, Moderna (advisory board), NIH, Doris Duke Foundation (grant review committee); C. Durand: Abbvie, GlaxoSmithKline (research support to institution), Gilead (grant review committee); D. Segev: CSL Behring (consulting), Novartis, Sanofi, Jazz Pharmaceuticals, Veloxis, Mallinckrodt, Thermo Fisher Scientific, Regeneron, AstraZeneca (honorarium, consulting). Data availability Proposals to access de-identified data from the CPAT trials can be submitted to the CPAT trials data coordinating center (contact: [email protected]), with transfer approved on an individual basis via formal data use agreement. Appendix A Supplementary data The following are the Supplementary data to this article:Multimedia component1 Multimedia component1 Multimedia component2 Multimedia component2 Appendix A Supplementary data to this article can be found online at https://doi.org/10.1016/j.ajt.2023.03.014. ==== Refs References 1 Boyarsky B.J. Werbel W.A. Avery R.K. Antibody response to 2-dose SARS-CoV-2 mRNA vaccine series in solid organ transplant recipients JAMA 325 21 2021 2204 2206 33950155 2 Yahav D. Rahamimov R. Mashraki T. Immune response to third dose BNT162b2 COVID-19 vaccine among kidney transplant recipients-a prospective study Transpl Int 35 2022 10204 3 Rincon-Arevalo H. Choi M. Stefanski A.L. Impaired humoral immunity to SARS-CoV-2 BNT162b2 vaccine in kidney transplant recipients and dialysis patients Sci Immunol 6 60 2021 eabj1031 4 Sun J. Zheng Q. Madhira V. Association between immune dysfunction and COVID-19 breakthrough infection after SARS-CoV-2 vaccination in the US JAMA Intern Med 182 2 2022 153 162 34962505 5 Gilbert P.B. Donis R.O. Koup R.A. Fong Y. Plotkin S.A. Follmann D. A Covid-19 milestone attained – a correlate of protection for vaccines N Engl J Med 387 24 2022 2203 2206 36507702 6 Charmetant X. Espi M. Benotmane I. Infection or a third dose of mRNA vaccine elicits neutralizing antibody responses against SARS-CoV-2 in kidney transplant recipients Sci Transl Med 14 636 2022 eabl6141 7 Kumar D. Hu Q. Samson R. Neutralization against Omicron variant in transplant recipients after three doses of mRNA vaccine Am J Transplant 22 8 2022 2089 2093 35266606 8 Karaba A.H. Johnston T.S. Aytenfisu T.Y. A fourth dose of COVID-19 vaccine does not induce neutralization of the omicron variant among solid organ transplant recipients with suboptimal vaccine response Transplantation 106 7 2022 1440 1444 35417115 9 Manothummetha K. Chuleerarux N. Sanguankeo A. Immunogenicity and risk factors associated with poor humoral immune response of SARS-CoV-2 vaccines in recipients of solid organ transplant: a systematic review and meta-analysis JAMA Netw Open 5 4 2022 e226822 10 Kantauskaite M. Müller L. Kolb T. Intensity of mycophenolate mofetil treatment is associated with an impaired immune response to SARS-CoV-2 vaccination in kidney transplant recipients Am J Transplant 22 2 2022 634 639 34551181 11 Mitchell J. Chiang T.P. Alejo J.L. Effect of mycophenolate mofetil dosing on antibody response to SARS-CoV-2 vaccination in heart and lung transplant recipients Transplantation 106 5 2022 e269 e270 35250006 12 Caillard S. Thaunat O. Benotmane I. Masset C. Blancho G. Antibody response to a fourth messenger RNA COVID-19 vaccine dose in kidney transplant recipients: a case series Ann Intern Med 175 3 2022 455 456 35007148 13 Midtvedt K. Vaage J.T. Heldal K. Munthe L.A. Lund-Johansen F. Åsberg A. Fourth dose of the SARS-CoV-2 vaccine in kidney transplant recipients with previously impaired humoral antibody response Am J Transplant 22 11 2022 2704 2706 35533010 14 Benotmane I. Gautier G. Perrin P. Antibody response after a third dose of the mRNA-1273 SARS-CoV-2 vaccine in kidney transplant recipients with minimal serologic response to 2 doses JAMA 326 11 2021 1063 1065 34297036 15 Alejo J.L. Chiang T.P.Y. Bowles Zeiser L. Incidence and severity of COVID-19 among vaccinated solid organ transplant recipients during the omicron wave Transplantation 106 9 2022 e413 e415 35655363 16 Caillard S. Chavarot N. Bertrand D. Occurrence of severe COVID-19 in vaccinated transplant patients Kidney Int 100 2 2021 477 479 34029554 17 Tau N. Yahav D. Schneider S. Rozen-Zvi B. Abu Sneineh M. Rahamimov R. Severe consequences of COVID-19 infection among vaccinated kidney transplant recipients Am J Transplant 21 8 2021 2910 2912 34043872 18 Hall V.G. Ferreira V.H. Ierullo M. Humoral and cellular immune response and safety of two-dose SARS-CoV-2 mRNA-1273 vaccine in solid organ transplant recipients Am J Transplant 21 12 2021 3980 3989 34347934 19 Schrezenmeier E. Rincon-Arevalo H. Stefanski A.L. B and T cell responses after a third dose of SARS-CoV-2 vaccine in kidney transplant recipients J Am Soc Nephrol 32 12 2021 3027 3033 34667083 20 Sattler A. Schrezenmeier E. Weber U.A. Impaired humoral and cellular immunity after SARS-CoV-2 BNT162b2 (tozinameran) prime-boost vaccination in kidney transplant recipients J Clin Invest 131 14 2021 e150175 21 Havlin J. Svorcova M. Dvorackova E. Immunogenicity of BNT162b2 mRNA COVID-19 vaccine and SARS-CoV-2 infection in lung transplant recipients J Heart Lung Transplant 40 8 2021 754 758 34120839 22 Departments of Research & Development and Product Management, for Roche Diagnostics Solutions, Core Lab. Correlation between Elecsys® Anti-SARS-CoV-2 S assay results and the detection of functional SARS-CoV-2 neutralizing antibodies Memo. February 8 2021 23 Resman Rus K. Korva M. Knap N. Avšič Županc T. Poljak M. Performance of the rapid high-throughput automated electrochemiluminescence immunoassay targeting total antibodies to the SARS-CoV-2 spike protein receptor binding domain in comparison to the neutralization assay J Clin Virol 139 2021 104820 24 Werbel W.A. Boyarsky B.J. Ou M.T. Safety and immunogenicity of a third dose of SARS-CoV-2 vaccine in solid organ transplant recipients: a case series Ann Intern Med 174 9 2021 1330 1332 34125572 25 Karaba A.H. Zhu X. Liang T. A third dose of SARS-CoV-2 vaccine increases neutralizing antibodies against variants of concern in solid organ transplant recipients Am J Transplant 22 4 2022 1253 1260 34951746 26 Karaba A.H. Kim J.D. Chiang T.P.Y. Neutralizing activity and 3-month durability of tixagevimab and cilgavimab prophylaxis against Omicron sublineages in transplant recipients Am J Transplant 23 3 2023 423 428 36906295 27 Klein S.L. Pekosz A. Park H.S. Sex, age, and hospitalization drive antibody responses in a COVID-19 convalescent plasma donor population J Clin Invest 130 11 2020 6141 6150 32764200 28 Schaecher S.R. Touchette E. Schriewer J. Buller R.M. Pekosz A. Severe acute respiratory syndrome coronavirus gene 7 products contribute to virus-induced apoptosis J Virol 81 20 2007 11054 11068 17686858 29 Carreño J.M. Alshammary H. Tcheou J. Activity of convalescent and vaccine serum against SARS-CoV-2 Omicron Nature 602 7898 2022 682 688 35016197 30 Shomuradova A.S. Vagida M.S. Sheetikov S.A. SARS-CoV-2 epitopes are recognized by a public and diverse repertoire of human T cell receptors Immunity 53 6 2020 1245 1257.e5 33326767 31 Oberhardt V. Luxenburger H. Kemming J. Rapid and stable mobilization of CD8+ T cells by SARS-CoV-2 mRNA vaccine Nature 597 7875 2021 268 273 34320609 32 Klinger M. Pepin F. Wilkins J. Multiplex identification of antigen-specific T cell receptors using a combination of immune assays and immune receptor sequencing PLOS ONE 10 10 2015 e0141561 33 Snyder T.M. Gittelman R.M. Klinger M. Magnitude and dynamics of the T-cell response to SARS-CoV-2 infection at both individual and population levels medRxiv 2020 10.1101/2020.07.31.20165647 34 Garcia-Beltran W.F. St Denis K.J. Hoelzemer A. mRNA-based COVID-19 vaccine boosters induce neutralizing immunity against SARS-CoV-2 Omicron variant Cell 185 3 2022 457 466.e4 34995482 35 Louis T.A. Zeger S.L. Effective communication of standard errors and confidence intervals Biostatistics 10 1 2009 1 2 18550565 36 Osmanodja B. Ronicke S. Budde K. Serological response to three, four and five doses of SARS-CoV-2 vaccine in kidney transplant recipients J Clin Med 11 9 2022 37 Schrezenmeier E. Rincon-Arevalo H. Jens A. Temporary antimetabolite treatment hold boosts SARS-CoV-2 vaccination-specific humoral and cellular immunity in kidney transplant recipients JCI Insight 7 9 2022 e157836 38 Kho M.M.L. Messchendorp A.L. Frölke S.C. Alternative strategies to increase the immunogenicity of COVID-19 vaccines in kidney transplant recipients not responding to two or three doses of an mRNA vaccine (RECOVAC): a randomised clinical trial Lancet Infect Dis 23 3 2023 307 319 36354032 39 Thompson E. Roznik K. Karaba A.H. Lipid-oxidizing B cells enable successful vaccine response despite immunosuppression Immunity. Posted online April 22 2022 10.2139/ssrn.4090935 40 Reynolds C.J. Pade C. Gibbons J.M. Immune boosting by B.1.1.529 (Omicron) depends on previous SARS-CoV-2 exposure Science 377 6603 2022 eabq1841 41 Ferreira V.H. Solera J.T. Hu Q. Homotypic and heterotypic immune responses to Omicron variant in immunocompromised patients in diverse clinical settings Nat Commun 13 1 2022 4489 35927279 42 Connolly C.M. Chiang T.P. Boyarsky B.J. Temporary hold of mycophenolate augments humoral response to SARS-CoV-2 vaccination in patients with rheumatic and musculoskeletal diseases: a case series Ann Rheum Dis 81 2 2022 293 295 34556484
PMC010xxxxxx/PMC10040228.txt	==== Front CJEM CJEM Cjem 1481-8035 1481-8043 Springer International Publishing Cham 36967408 485 10.1007/s43678-023-00485-3 Original Research Fear, health impacts, and life delays: residents’ certification exam year experience http://orcid.org/0000-0001-7562-1141 Onlock Michelle 1 http://orcid.org/0000-0003-3347-7107 Nasser Laila 12 http://orcid.org/0000-0002-5720-5002 Riddell Tara 3 http://orcid.org/0000-0003-3850-6595 Snelgrove Natasha 4 http://orcid.org/0000-0003-3628-2241 Pardhan Kaif [email protected] 145 1 grid.17063.33 0000 0001 2157 2938 Department of Medicine, University of Toronto, Toronto, ON Canada 2 grid.25073.33 0000 0004 1936 8227 Department of Medicine, McMaster University, Hamilton, ON Canada 3 grid.25073.33 0000 0004 1936 8227 Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON Canada 4 grid.25073.33 0000 0004 1936 8227 Department of Pediatrics, McMaster University, Hamilton, ON Canada 5 grid.17063.33 0000 0001 2157 2938 University of Toronto and McMaster University, Toronto, ON Canada 26 3 2023 2023 25 6 468474 23 1 2023 28 2 2023 © The Author(s), under exclusive licence to Canadian Association of Emergency Physicians (CAEP)/ Association Canadienne de Médecine d'Urgence (ACMU) 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Background Residency training is associated with risks of burnout and impaired well-being. This may be due to multiple factors, including navigating various transitions. Chief among these is the transition to independent practice which, in Canada, involves a certification exam administered by the Royal College of Physicians and Surgeons of Canada or the College of Family Physicians of Canada. This qualitative study explored the experience of residents in their examination year, including residents impacted by pandemic-related examination postponment, to understand how these experiences may impact residents’ well-being. Methods Qualitative description methodology was used for this study. Participants were residents and physicians in independent practice from McMaster University and the University of Toronto. In depth, semi-structured, one-on-one interviews were conducted by one of the investigators. Each was transcribed, reviewed, and coded by two members of the investigating team. Results Five themes were identified. Examinations were perceived to be a significant stressor, and the extent of preparation involved was viewed as a threat to one’s physical and mental well-being. Participants identified a culture of fear surrounding the exam, as well as a perception that exam preparation requires significant sacrifice which can exacerbate the impacts of the exam year. Personal and professional supports were identified as important protective factors. Conclusion This study has identified unique challenges in the examination year, and its impact on the well-being of residents immediately before they enter independent practice. Residents also experienced significant learning and a sense of accomplishment through their preparation for the examination. The COVID-19 pandemic had a unique impact on one cohort of residents. This should prompt medical education institutions to examine the support provided to residents, the culture surrounding certification examinations, and mitigation strategies for future examination disruptions. Résumé Contexte La formation en résidence est associée à des risques d'épuisement professionnel et de bien-être altéré. Cela peut être dû à plusieurs facteurs, y compris la navigation dans diverses transitions. La principale d'entre elles est la transition vers la pratique indépendante qui, au Canada, implique un examen de certification administré par le Collège royal des médecins et chirurgiens du Canada ou le Collège des médecins de famille du Canada. Cette étude qualitative a exploré l'expérience des résidents au cours de leur année d'examen, y compris les résidents touchés par le report d'examen lié à la pandémie, afin de comprendre comment ces expériences peuvent avoir un impact sur le bien-être des résidents. Méthodes Une méthodologie de description qualitative a été utilisée pour cette étude. Les participants étaient des résidents et des médecins en pratique indépendante de l'Université McMaster et de l'Université de Toronto. Des entretiens individuels approfondis et semi-structurés ont été menés par l'un des enquêteurs. Chaque entretien a été transcrit, revu et codé par deux membres de l'équipe d'enquêteurs. Résultats Cinq thèmes ont été identifiés. Les examens étaient perçus comme un facteur de stress important, et l'ampleur de la préparation était considérée comme une menace pour le bien-être physique et mental. Les participants ont identifié une culture de la peur autour de l'examen, ainsi que la perception que la préparation à l'examen exige des sacrifices importants, ce qui peut exacerber les impacts de l'année de l'examen. Les soutiens personnels et professionnels ont été identifiés comme d'importants facteurs de protection. Conclusion Cette étude a permis d'identifier les défis uniques de l'année d'examen et son impact sur le bien-être des résidents juste avant qu'ils entrent en pratique indépendante. Les résidents ont également fait l'expérience d'un apprentissage important et d'un sentiment d'accomplissement tout au long de leur préparation à l'examen. La pandémie de COVID-19 a eu un impact unique sur une cohorte de résidents. Cela devrait inciter les établissements d'enseignement médical à examiner les soutiens apportés aux résidents, la culture entourant les examens de certification et les stratégies d'atténuation des perturbations futures des examens. Keywords Medical education Residency Examinations Assessment Wellness Burnout issue-copyright-statement© Canadian Association of Emergency Physicians (CAEP)/ Association Canadienne de Médecine d'Urgence (ACMU) 2023 ==== Body pmcClinician’s capsule What is known about the topic? Transitioning to independent practice in Canada requires completion of a high stakes certification examination. What did this study ask? What is the experience of residents in the year of their certification examination? What did this study find? Residents perceive deleterious physical and mental health impacts in their examination year, driven by stress and the culture surrounding the examination. Why does this study matter to clinicians? Impaired wellness may impact quality of care. Mitigating the wellness impacts of the examination year may ease residents’ transition to practice. Introduction Physicians devote their careers to preventing harm, alleviating suffering, and promoting the well-being of others [1, 2]. Physicians’ well-being may decline over the course of their training [3]. Medical training, and specifically postgraduate residency training, is a time when physicians’ well-being may be most negatively impacted. Multiple authors have identified lower quality of life, burnout, depression, and suicidal ideation, as being prevalent and rising amongst residents [4–7]. Despite reported high degrees of resilience, residents are negatively affected by their training experience [7]. Brazeau and colleagues identified that residents generally begin training with better well-being than the general population, suggesting changes in their well-being may be driven by their learning and work environment [8]. Contributing factors, identified by Dyrbye, include excessive workload and administrative tasks, work hours and call frequency, limited autonomy and lack of control, and juggling the dual roles of physician and learner [9]. Residency training is notable for the number and frequency of professional transitions. In Canada, transition to practice requires residents to complete a certification examination, offered once annually, administered by the Royal College of Physicians and Surgeons of Canada (RCPSC) or the College of Family Physicians of Canada (CFPC). These have been identified by both medical regulators and the public as important point-in-time measurements [10, 11] and there is some evidence, from the United States, that the public values board certification [12]. Residents prepare while continuing to work clinically and fulfilling academic responsibilities. Further, there is an absence of evidence showing that performance on the certification examination is associated with improved outcomes. These factors may provoke increased stress and be detrimental to residents’ wellness. High-stakes assessments in undergraduate medical education (UGME) provoke stress and anxiety, in part, due to the intensity of preparation and pressure to be successful [13–15]. There has been a paucity of literature exploring the impact of examinations in postgraduate medical education (PGME). Residency is distinct from UGME in that there is a single high-stakes examination at the conclusion of training [16] with a significant impact on independent licensure [17]. This study seeks to explore the experiences of residents in the certification exam year and its impact on their personal and professional lives. This study coincided with the emergence of the COVID-19 pandemic, which led to disruptions in training, examinations, and licensure [18–22], and this study also explores those experiences. The insights from this study may identify how impacts from the exam year in general, and future exam disruptions in particular, may be mitigated for residents. Methods This study used qualitative description to explore our research questions. Qualitative description provides “a comprehensive summary of an event in the everyday terms of those events” [23]. No specific theoretical framework was applied to this research prior to data analysis, as is common in this methodology [24]. We deemed this approach the most appropriate as the goal of our research was not to create or build on theory but to stay close to the data, to deeply understand participants’ experiences in their exam year [24]. The study team was composed of three resident physicians (LN, MO, and TR) and two physicians in independent practice (KP and NS). One author (MO) was a resident in the certification exam year during the study period and two authors (KP and NS) had both completed their certification exams within the previous 5 years. All authors remained reflexively aware of their status as insider researchers and its impact on their approach to the data and how it was processed [25–27]. This research was conducted at the University of Toronto and McMaster University, which are large- and medium-sized Canadian universities. The work was approved by the Sunnybrook Health Sciences Centre Research Ethics Board and the Hamilton Integrated Research Ethics Board. Recruitment occurred via snowball sampling. Our intent was to recruit a wide variety of representative certification exam year residents and recent certificants across a wide number of specialties. The resident physicians on the research team reached out to potential resident participants, while the independently practicing physicians on the research team did so for the potential independently practicing participants. Participation was voluntary. Due to potential variability in exam year experience based on specialty and exam structure, the goal of this study was to achieve a broad sampling to determine the generalities that would hold true across programs. Recruitment and data analysis occurred concurrently. Twenty-one physicains participated in this study: Fourteen residents in their certification exam year and seven recent certificants in independent practice were recruited from various medical and surgical specialties. Data collection was done via individual, semi-structured interviews. Participants were asked about their examination year experience and its impact on their personal and professional lives. The interview guide was updated iteratively during data collection to reflect emerging themes. All interviews were recorded and transcribed verbatim. Data were initially analysed by line-by-line coding. Similar initial codes were then combined, and the new code set was used to code future transcripts. All were coded by two members of the research team to improve analytic rigour [28]. The research team kept memos during the analysis process to record insights and reflections. Data gathering was continued until thematic sufficiency was achieved [29] and differences were resolved by consensus. Results Analysis of participant responses revealed five themes. The certification examination year as a source of stress. Exam preparation caused deleterious physical and mental health impacts. There was a culture of fear. There was a balance between investments versus loss. Personal and professional supports were identified as protective. These themes are further illuminated through quotes from study participants below. Examination as a significant source of stress High degrees of stress were noted related to exam preparation, career and family planning, and uncertainty regarding future employment. The most significant source of stress was the fear of failure: “There was just constant fear, fear of failure” (Participant C) which was exacerbated if: “… people failed the exam with regularity”. (Participant G). Career planning while studying added an additional layer of stress: “…there is a culture of… fear mongering…Your residency [and] future employment hinges on it” (Participant F). The impact of the multiple roles held by residents was also highlighted: “[they] have a role as a learner, … [and] as a healthcare provider…Truly it’s that last one that they’re getting paid for…”. (Participant I). While these roles are generally complementary, the focus on exam success may lead to a perception of role conflict. Many participants identified the fact that certification exams often coincided with major life milestones including starting, or caring for, a family “for me the most stressful part was explaining it to my wife … this year and the bulk of [my daughter’s] infancy through studying … and … I’ve been fairly absent. [My wife]’s been picking up all the slack” (Participant K). This stress was further exacerbated by COVID-19-related postponement and perceived poor communication about both the postponement and its consequences: “You spend so much of the year trying to manage studying…trying to…balance everything…And then you’re told that it’s postponed…and then you don’t have any kind of ideas as to what work is going to look like” (Participant P). Exam year risks deleterious physical and mental health impacts Participants felt their physical health was impacted, including decreased exercise and diet changes “I no longer cook” (Participant C); “I felt like it was justified to go and get candy or chips” (Participant E). The cumulative effects of these habits contributed to weight gain: “Overeating, not exercising, constantly sitting and studying” (Participant A). Sleep was also impacted by the perceived lack of time “I was probably only sleeping three or four hours a day… [it was] my wrap-up strategy” (Participant L). Participants also noted negative impacts on mental health: “I thought I started having signs of clinical depression … [I] tried to augment it with Vitamin D…light …[then] I started taking [antidepressants].” (Participant K). Culture of fear enshrouds the examination year Participants noted a cultural norm where the exam will be all consuming: “…bracing yourself for a year that you have absolutely no life, ‘The worst year of your life…You’re going to be at your most miserable…let your friends and family know’” (Participant C). Some participants felt the expectation was that they should put their life “on pause”: “advice was, it’s a tough year…don’t do anything crazy…like get married or have a baby” (Participant F). Many participants had advice for future exam candidates based on how they wished they had done things differently: “I wish I could go back … [the] hours…that I committed to…Ranson’s criteria that I still don't know now… [Keep] up with other things that are important to you” (Participant F). Residents impacted by COVID-19 were also aware of the culture surrounding exam completion and begnning their careers: “I’m doing a fellowship…to fund my fellowship…I was planning on doing locum calls…the hospitals are not interested in having me…until I’ve written my exam” (Participant U). Perception of examination as an investment versus loss Participants noted that exam preparation is also a valuable investment: “I definitely felt that I was even more knowledgeable” (Participant A). It enhanced their sense of belonging and confidence that they were ready for practice: “you become a member of a club…Attendings are genuinely asking you for your opinions when they get into difficult situations” (Participant K). There was an emphasis on the cost that the exam exacted, particularly as it related to time spent on other important portions of participants’ lives. Those who had already completed their exams relayed a sense of regret that they had allowed the exam to consume their life: “Everything you do has a cost… If you have small children make sure you spend the time with them … you don’t get that back” (Participant G). Personal and professional supports are protective Support from peers, program, and family was frequently described by participants as important. Shared experiences with their peers afforded participants opportunities to feel less alone, to debrief, and to encourage, motivate, and emotionally comfort one another: “it was motivating …I’m not sure if I would have been able to get through it on my own” (Participant C). Program-specific and system-level supports were also identified by participants as important “A supportive program that’s willing to listen… I think that can really impact how you do in the exam and your well-being” (Participant E). This was also particularly true during the COVID-19 pandemic “Medicine staff were staying in-house doing call overnight” (Participant O). Program directors, faculty, and mentors were all identified as sources of emotional support “[They] banded together to empathize with us” (Participant T). Validation of residents’ experiences, normalizing the difficulty, and establishing a compassionate cultural tone were all important. “[They] can give you like a realistic picture…I thought I was going to fail and I called my assistant program director and she just basically talked me off of a ledge” (Participant F). Discussion Interpretation and alignment with previous work Residency is an integral part of physicians’ growth and training. It is a transformative period marked by growth in knowledge, professional identity formation, and enculturation [30]. However, their well-being may suffer [5] due to the rigor of training, health system challenges, and frequent transitions in training. Transitioning to residency is a source of stress with increased responsibilities, work demands, transfer of knowledge, and coping with adverse events [31–33]. Our study suggests that the experience of preparing for the certification examination, and its role in transitioning to independent practice, may also be a significant source of stress and have significant impacts on residents’ personal and professional lives. This aligns with the findings of Lyndon and collegues’ systematic review of assessment and psychological distress in UGME [13] and with Jenkins and colleagues’ findings regarding stress at the time of the USMLE Step 1[14]. This study brings a new lens to the previously published work. Participants noted delaying milestones, including starting a family, which may already be fraught during training [34], as well as impacts on childrearing, previously explored by Spruce and colleageus [35]. While Lyndon, Jenkins and their colleagues noted the stress related to assessment [13, 14], our participants went further, delineating a relationship between their success, their career, and stigma associated with failure, which may all be perpetuated in the hidden curriculum. The findings of this study suggest that the certification exam year may be an important factor, in addition to many others [36], in our understanding of burnout in residents and new in practice physicians, which can have deleterious impacts on them, their patients, and the health system more broadly [37, 38]. The COVID-19 pandemic had an impact on our participants. Despite the impact on their clinical work, examinations, and licensure [18, 22, 39], they were clear eyed with respect to the local, national, and global disruption caused by the pandemic. Strengths and limitations This study’s strengths rested in staying close to the participants’ experiences of the certification exam year, and its ability to respond to an emerging event that impacted its subjects directly. Its limitations included interviews being conducted at one medium and one large university, which may not reflect the culture and experiences and smaller institutions. We used snowball sampling and we stopped recruitment when sufficiency was met. It is possible that additional themes may have emerged with further recruitment. It may be beneficial in future research to look at the differences between specialties in more detail. Implications in medical education Participants noted the significant learning and enculturation that occurred as a consequence of their studying, aligning with Norcini and colleagues’ criteria for a good assessment, including educational and catalytic effects [40]. However, the hidden curriculum appeared to negatively influence our participants and how they studied, potentially pushing them to over-prepare and miss out on key life events. Programs and PGME offices are well positioned to provide credible guidance and mitigate the influence of well-intentioned peers and supervisors who may be exacerbating candidates’ stress. Further, the reported health effects of preparing for the examination and the prevalence of burnout in early career physicians may help stimulate a conversation regarding the role of a single high-stakes examination as a requirement for entry into independent practice, particularly in a competency-based medical education environment. This study also coincided with the global emergence of COVID-19. The pandemic significantly disrupted the provision of certification examinations in 2020 and delayed full licensure, leading to uncertainty for residents and in the Canadian health workforce. Multiple viruses have disrupted healthcare and education in the last two decades, with Severe Acute Respiratory Syndrome (SARS) having also affected medical education [41–43]. Climate change may continue to exacerbate certification examination disruption from both disease transmission as well as severe weather events [44–46]. In the face of COVID-19, stakeholders adapted the delivery of examinations and increased support to residents. This demonstrates that Canadian medical institutions are well positioned to engage in discussions about examinations and address the challenges identified in this study. Conclusion Residents experience significant personal and professional stress and negative health outcomes during their examination year. This stress is exacerbated by the culture surrounding the certification examination and the personal sacrifices that are made to succeed. Preparation for the examination also prompted significant learning and a sense of accomplishment. COVID-19-related examination disruptions added a unique stressor for residents in 2020. The stress-related health impacts of the exam year are a factor that stakeholders should consider when supporting residents in their transition to practice. Funding None. Data availability The data that support the findings of this study are not openly available to ensure participant anonymity. De-identified and anonymized transcripts are available from the corresponding author upon reasonable request. Declarations Conflict of interest Dr. Pardhan is a member of the Royal College of Physicians and Surgeons of Canada Council. ==== Refs References 1. Canadian Medical Association. Seizing the moment - Impact 2040 strategy 2022 [Available from: https://www.cma.ca/seizing-moment-impact-2040-strategy. 2. Eisenberg C Reynolds R Stone J It Is Still A Privilege To Be A Doctor On Doctoring 2001 3 New York Simon and Schuster 19 21 3. Mihailescu M Neiterman E A scoping review of the literature on the current mental health status of physicians and physicians-in-training in North America BMC Public Health 2019 19 1 1363 10.1186/s12889-019-7661-9 31651294 4. West CP Shanafelt TD Kolars JC Quality of life, burnout, educational debt, and medical knowledge among internal medicine residents JAMA 2011 306 9 952 960 10.1001/jama.2011.1247 21900135 5. Dyrbye LN West CP Satele D Boone S Tan L Sloan J Burnout among U.S. medical students, residents, and early career physicians relative to the general U.S. population Acad Med 2014 89 3 443 451 10.1097/ACM.0000000000000134 24448053 6. Mata DA Ramos MA Bansal N Khan R Guille C Di Angelantonio E Prevalence of depression and depressive symptoms among resident physicians: a systematic review and meta-analysis JAMA 2015 314 22 2373 2383 10.1001/jama.2015.15845 26647259 7. CMA National Physician Health Survey Ottawa 2018 Canada Canadian Medical Association 8. Brazeau CM Shanafelt T Durning SJ Massie FS Eacker A Moutier C Distress among matriculating medical students relative to the general population Acad Med 2014 89 11 1520 1525 10.1097/ACM.0000000000000482 25250752 9. Dyrbye L Shanafelt T A narrative review on burnout experienced by medical students and residents Med Educ 2016 50 1 132 149 10.1111/medu.12927 26695473 10. Norcini JJ Lipner RS Grosso LJ Assessment in the context of licensure and certification Teach Learn Med 2013 25 Suppl 1 S62 S67 10.1080/10401334.2013.842909 24246109 11. Maudsley RF Medical licensure: let’s not lose sight of the objective CMAJ 1990 143 2 98 100 2364343 12. Freed GL Dunham KM Clark SJ Davis MM Research Advisory Committee of the American Board of P Perspectives and preferences among the general public regarding physician selection and board certification J Pediatr 2010 156 5 841 845 10.1016/j.jpeds.2009.11.055 20138304 13. Lyndon MP Strom JM Alyami HM Yu TC Wilson NC Singh PP The relationship between academic assessment and psychological distress among medical students: a systematic review Perspect Med Educ 2014 3 6 405 418 10.1007/S40037-014-0148-6 25428333 14. Jenkins TM Kim J Hu C Hickernell JC Watanaskul S Yoon JD Stressing the journey: using life stories to study medical student wellbeing Adv Health Sci Educ Theory Pract 2018 23 4 767 782 10.1007/s10459-018-9827-0 29730708 15. Radcliffe C Lester H Perceived stress during undergraduate medical training: a qualitative study Med Educ 2003 37 1 32 38 10.1046/j.1365-2923.2003.01405.x 12535113 16. Royal College of Physicians and Surgeons of Canada. Exams: Deadlines, dates and locations 2022 [Available from: https://www.royalcollege.ca/rcsite/credentials-exams/exams-dates-locations-e. 17. College of Physicians and Surgeons of Ontario. Registration Requirements 2022 [Available from: https://www.cpso.on.ca/en/Physicians/Registration/Requirements. 18. Hall AK Nousiainen MT Campisi P Dagnone JD Frank JR Kroeker KI Training disrupted: practical tips for supporting competency-based medical education during the COVID-19 pandemic Med Teach 2020 42 7 756 761 10.1080/0142159X.2020.1766669 32450049 19. Brown A Kassam A Paget M Blades K Mercia M Kachra R Exploring the global impact of the COVID-19 pandemic on medical education: an international cross-sectional study of medical learners Can Med Educ J 2021 12 3 28 43 34249189 20. CFPC. Impact of COVID-19 on Certification and Examinations: College of Family Physicians of Canada; 2020 [Available from: https://www.cfpc.ca/en/education-professional-development/examinations-and-certification/certification-examination-in-family-medicine/impact-of-covid-19-on-certification-and-examinati. 21. RCPSC. Impact on Royal College exams: Royal College of Physicians and Surgeons of Canada; 2020 [Available from: http://www.royalcollege.ca/rcsite/documents/about/update-coronavirus-e. 22. Owens B Exam delays throw residents’ careers into limbo CMAJ 2020 192 15 E413 E414 10.1503/cmaj.1095858 32392506 23. Sandelowski M Whatever happened to qualitative description? Res Nurs Health 2000 23 4 334 340 10.1002/1098-240X(200008)23:4<334::AID-NUR9>3.0.CO;2-G 10940958 24. Neergaard MA Olesen F Andersen RS Sondergaard J Qualitative description—the poor cousin of health research? BMC Med Res Methodol 2009 9 52 10.1186/1471-2288-9-52 19607668 25. Breen LJ The researcher ‘in the middle’: negotiating the insider/outsider dichotomy Aust Community Psychol. 2007 19 1 163 174 26. Bonner A Tolhurst G Insider-outsider perspectives of participant observation Nurse Res 2002 94 4 7 19 10.7748/nr2002.07.9.4.7.c6194 27. Adler P, Adler P. 1994 Observational techniques. In: NK D, YS L eds. Handbook of qualitative research. Thousand Oaks, California: Sage. 377–92. 28. Watling CJ Lingard L Grounded theory in medical education research: AMEE Guide No. 70 Med Teach 2012 34 10 850 861 10.3109/0142159X.2012.704439 22913519 29. Vasileiou K Barnett J Thorpe S Young T Characterising and justifying sample size sufficiency in interview-based studies: systematic analysis of qualitative health research over a 15 year period BMC Med Res Methodol 2018 18 1 148 10.1186/s12874-018-0594-7 30463515 30. Cruess RL Cruess SR Boudreau JD Snell L Steinert Y Reframing medical education to support professional identity formation Acad Med 2014 89 11 1446 1451 10.1097/ACM.0000000000000427 25054423 31. Hurst C Kahan D Ruetalo M Edwards S A year in transition: a qualitative study examining the trajectory of first year residents' well-being BMC Med Educ 2013 13 96 10.1186/1472-6920-13-96 23842470 32. Brennan N Corrigan O Allard J Archer J Barnes R Bleakley A The transition from medical student to junior doctor: today’s experiences of tomorrow’s Doctors Med Educ 2010 44 5 449 458 10.1111/j.1365-2923.2009.03604.x 20518984 33. Teunissen PW Westerman M Opportunity or threat: the ambiguity of the consequences of transitions in medical education Med Educ 2011 45 1 51 59 10.1111/j.1365-2923.2010.03755.x 21155868 34. Huynh M Wang A Ho J Herndon CN Aghajanova L Fertility preservation and infertility treatment in medical training: an assessment of residency and fellowship program directors’ attitudes Womens Health Rep (New Rochelle) 2021 2 1 576 585 35141706 35. Spruce MW Gingrich AA Phares A Beyer CA Salcedo ES Guralnick S Child-rearing during postgraduate medical training and its relation to stress and burnout: results from a single-institution multispecialty survey Mil Med 2022 187 3–4 e518 e526 10.1093/milmed/usab029 33580698 36. Berger L Waidyaratne-Wijeratne N Where does resiliency fit into the residency training experience Can Med Educ J 2019 10 1 e20 e27 10.36834/cmej.42992 30949258 37. West CP Dyrbye LN Shanafelt TD Physician burnout: contributors, consequences and solutions J Intern Med 2018 283 6 516 529 10.1111/joim.12752 29505159 38. Dewa CS Jacobs P Thanh NX Loong D An estimate of the cost of burnout on early retirement and reduction in clinical hours of practicing physicians in Canada BMC Health Serv Res 2014 14 254 10.1186/1472-6963-14-254 24927847 39. Ormsby M Some Canadian medical residents are on the pandemic front lines now, but exams to become licesned doctors are in limbo Toronto Star 2020 2 2020 40. Norcini J Anderson B Bollela V Burch V Costa MJ Duvivier R Criteria for good assessment: consensus statement and recommendations from the Ottawa 2010 Conference Med Teach 2011 33 3 206 214 10.3109/0142159X.2011.551559 21345060 41. Rieder MJ Salvadori M Bannister S Kenyon C Collateral damage: the effect of SARS on medical education Clin Teach 2004 1 2 85 89 10.1111/j.1743-498X.2004.00026.x 42. Sherbino J Atzema C “SARS-Ed”: severe acute respiratory syndrome and the impact on medical education Ann Emerg Med 2004 44 3 229 231 10.1016/j.annemergmed.2004.05.021 15332063 43. Rambaldini G Wilson K Rath D Lin Y Gold WL Kapral MK The impact of severe acute respiratory syndrome on medical house staff: a qualitative study J Gen Intern Med 2005 20 5 381 385 10.1111/j.1525-1497.2005.0099.x 15963157 44. Crawford BE Kahn MJ Gibson JW Daniel AJ Krane NK Impact of Hurricane Katrina on medical student academic performance: the Tulane experience Am J Med Sci 2008 336 2 142 146 10.1097/MAJ.0b013e318180f1b7 18703910 45. WHO. Managing epidemics: key facts about major deadly diseases. Geneva: World Health Organization; 2018. 46. Patz J Githeko A McCarty J Hussein S Confalonieri U de Wet N McMichael A Campbell-Lendrum D Corvalán C Ebi K Githeko A Scheraga J Climate change and infectious diseases Climate change and human health: risks and responses 2003 Geneva World Health Organization 103 132
PMC010xxxxxx/PMC10043952.txt	==== Front Curr Probl Cardiol Curr Probl Cardiol Current Problems in Cardiology 0146-2806 1535-6280 Elsevier S0146-2806(23)00145-7 10.1016/j.cpcardiol.2023.101728 101728 Article Nationwide Analysis of Cardiac Arrest Outcomes During the COVID-19 Pandemic Isath Ameesh MBBS a⁎ Malik Aaqib MD a Bandyopadhyay Dhrubajyoti MD a Goel Akshay MB a Rosenzveig Akiva BS b Cooper Howard A. MD a Panza Julio A. MD a a Department of Cardiology, Westchester Medical Center and New York Medical College, Valhalla, NY b School of Medicine, New York Medical College, Valhalla, NY ⁎ Corresponding author. Ameesh Isath, MBBS, Department of Cardiology, Westchester Medical Center, New York Medical College, Valhalla, NY. 28 3 2023 8 2023 28 3 2023 48 8 101728101728 . 2023 Elsevier Inc. Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. The coronavirus disease 2019 (COVID-19) pandemic had a significant impact on the chain of survival following cardiac arrest. However, large population-based reports of COVID-19 in patients hospitalized after cardiac arrest are limited. The National Inpatient Sample database was queried for cardiac arrest admissions during 2020 in the United States. Propensity score matching was used to match patients with and without concurrent COVID-19 according to age, race, sex, and comorbidities. Multivariate logistic regression analysis was used to identify predictors of mortality. A weighted total of 267,845 hospitalizations for cardiac arrest were identified, among which 44,105 patients (16.5%) had a concomitant diagnosis of COVID-19. After propensity matching, cardiac arrest patients with concomitant COVID-19 had higher rate of acute kidney injury requiring dialysis (64.9% vs 54.8%) mechanical ventilation >24 hours (53.6% vs 44.6%) and sepsis (59.4% vs 40.4%) compared to cardiac arrest patients without COVID-19. In contrast, cardiac arrest patients with COVID-19 had lower rates of cardiogenic shock (3.2% vs 5.4%, P < 0.001), ventricular tachycardia (9.6% vs 11.7%, P < 0.001), and ventricular fibrillation (6.7% vs 10.8%, P < 0.001), and a lower utilization of cardiac procedures. In-hospital mortality was higher in patients with COVID-19 (86.9% vs 65.5%, P < 0.001) and, on multivariate analysis, a diagnosis of COVID-19 was an independent predictor of mortality. Among patients hospitalized following a cardiac arrest during 2020, concomitant COVID-19 infection was associated with significantly worse outcomes characterized by an increased risk of sepsis, pulmonary and renal dysfunction, and death. ==== Body pmcIntroduction Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), was first detected in the United States in January 2020, and there have subsequently been more than 96 million confirmed cases.1 The COVID-19 pandemic evolved into a public health crisis which negatively impacted health systems around the world.2 Prior studies have established that there was a significant increase in cardiac arrests during the COVID-19 pandemic.3 , 4 An epidemiological study from France demonstrated that the incidence of cardiac arrest doubled during the pandemic compared to the prepandemic period, while a report from New York demonstrated a ∼3 fold increase.5 , 6 Prior to the COVID-19 pandemic, the mortality rate in hospitalized patients with cardiac arrest had been decreasing.7 However, resuscitation of patients with cardiac arrest, which is dependent on rapid coordinated efforts forming the chain of survival, was adversely affected by COVID-19.3 , 8 In keeping with this, reduced survival of cardiac arrest patients during the pandemic has been reported.3 , 4 A metanalysis by Teoh et al.9 reported ∼2 times increase in mortality following cardiac arrest during the COVID-19 pandemic. However, large-scale studies evaluating the impact of COVID-19 on hospitalized cardiac arrest patients in the United States have been limited. We performed a population-based analysis using a large, nationally representative database to compare the characteristics and outcomes of adult patients hospitalized with cardiac arrest with and without concomitant COVID-19 in the United States. We also aimed to identify clinical variables associated with increased mortality in these patients. Methods Data Source The publicly available Nationwide Inpatient Sample (NIS) provides a nationally-representative sample of 20% of all discharges from US community hospitals (approximately 8 million hospital discharges per year), making it the largest inpatient data set in the United States. The NIS database has been validated to provide reliable estimates of admissions and outcomes of hospitalizations. Discharge weights provided by the Agency for Healthcare Research and Quality may be utilized to calculate national estimates. Data for the year 2020 was made publicly available in September 2022. The NIS database included de-identified patient information, thereby exempting it from institutional review board. Study Population We included all hospitalizations of patients ≥18 years of age during calendar year 2020 with a diagnosis of cardiac arrest (International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code I46). We further classified patients according to whether or not there was a concomitant diagnosis of COVID-19 (ICD-10-CM code U07.1). In addition, we compared these results to those of cardiac arrest hospitalizations in 2019. Outcomes The primary outcome of this analysis was in-hospital mortality. Secondary outcomes included AKI requiring dialysis, respiratory failure requiring mechanical ventilation, deep vein thrombosis, pulmonary embolism, sepsis, cardiogenic shock and ventricular arrythmias. The use of intra-aortic balloon pump, percutaneous microaxial flow pump (Impella), or extracorporeal membrane oxygenation (ECMO) was examined. Length of stay and average hospital costs were also assessed. Statistical Analysis Statistical analyses were performed using Stata 16.0 (StataCorp. 2019. Stata Statistical Software: Release 16. College Station, TX: StataCorp LLC) and R (R Development Core Team, Vienna, Austria). Categorical variables are reported as percentages and continuous variables as median and interquartile range. Categorical variables were compared using the Pearson chi-square test and continuous variables using the student's t test. Using multivariable logistic regression, a propensity score was calculated for each patient using the variables in Table 1 . Propensity score matching without a replacement was performed in a 1:1 nearest-neighbor fashion, with a caliper width of 0.1 of the estimated propensity score. Logistic regression models were then generated to identify independent multivariate predictors of outcomes, and are reported as adjusted odds ratio (aOR) with 95% confidence intervals (CI). All reported P values are 2-sided, and a value of <0.05 was considered significant.TABLE 1 Baseline characteristics of hospitalizations for cardiac arrest stratified by COVID-19 TABLE 1 Pre-match cohort Post-match cohort No COVID (n = 223,740) COVID-19 (n = 44,105) P value No COVID-19 (n = 43,340) COVID-19 (n= 43,340) P value Age 64.0 (17.8) 67.0 (14.7) <0.001 67.5 (15.6) 66.9 (14.7) P = 0.03 Male 128,905(57.5%) 26,955(61.1%) <0.001 25,415(59.4%) 25,735(60.2%) 0.3 Ethnicity Caucasians 134,935 (60.3%) 16,870 (38.2%) <0.001 17,195 (39.7%) 16,865 (38.9%) P = 0.39 African Americans 43,795 (19.6%) 10,280 (23.3%) <0.001 10,350 (23.9%) 10,255 (23.7%) P = 0.76 Hispanics 21,740 (9.7%) 11,385 (25.8%) <0.001 10,495 (24.2%) 10,690 (24.7%) P = 0.57 Comorbidities Atrial fibrillation 49,125 (22.0%) 9655 (21.9%) 0.89 9785 (22.6%) 9530 (22.0%) P = 0.36 Diabetes Mellitus 82,860 (37.0%) 23,880 (54.1%) <0.001 23,245 (53.6%) 23,215 (53.6%) P = 0.93 Hypertension 150,400 (67.2%) 32,975 (74.8%) <0.001 32,885 (75.9%) 32,320 (74.6%) P = 0.05 Chronic kidney disease 68,825 (30.8%) 15,055 (34.1%) <0.001 15,170 (35.0%) 14,865 (34.3%) P = 0.34 Heart failure 96,780 (43.3%) 12,885 (29.2%) <0.001 19,050 (44.0%) 12,770 (29.5%) P < 0.001 Peripheral vascular disease 24,630 (11.0%) 2505 (5.7%) <0.001 2755 (6.4%) 2505 (5.8%) P = 0.11 Dementia 17,140 (7.7%) 5210 (11.8%) <0.001 5345 (12.3%) 5100 (11.8%) P = 0.26 COPD 58,750 (26.3%) 9745 (22.1%) <0.001 10,225 (23.6%) 9615 (22.2%) P < 0.05 Valvular disease 24,965 (11.2%) 2485 (5.6%) <0.001 2450 (5.7%) 2485 (5.7%) P = 0.82 Cardiac Arrhythmias 127,140(56.8%) 21,205(48.1%) <0.001 23,800 (54.9%) 20,895 (48.2%) P < 0.001 Liver Disease 42,725 (19.1%) 5990 (13.6%) <0.001 8005 (18.5%) 5895 (13.6%) P < 0.001 Hypothyroidism 26,375 (11.8%) 5295 (12.0%) 0.55 5125 (11.8%) 5190 (12.0%) P = 0.76 Anemia 13,220 (5.9%) 2045 (4.6%) <0.001 2100 (4.8%) 2020 (4.7%) P = 0.55 Cancer 22,905 (10.2%) 1490 (3.4%) <0.001 1480 (3.4%) 1490 (3.4%) P = 0.94 Coagulopathy 44,205 (19.8%) 10,800 (24.5%) <0.001 10,215 (23.6%) 10,435 (24.1%) P = 0.48 Obesity 38,545 (17.2%) 12,185 (27.6%) <0.001 11,675 (26.9%) 11,715 (27.0%) P = 0.89 Coronary artery disease 74,965 (33.5%) 10,470 (23.7%) <0.001 3825 (8.8%) 3890 (9.0%) P = 0.72 Prior Stroke 21,015 (9.4%) 3930 (8.9%) 0.15 2100 (4.8%) 2060 (4.8%) P = 0.77 Location/teaching status of hospital P < 0.001 P < 0.001 Rural 13,555 (6.1%) 2940 (6.7%) 2350 (5.4%) 2925 (6.7%) Urban nonteaching 39,475 (17.6%) 8825 (20.0%) 7530 (17.4%) 8685 (20.0%) Urban teaching 170,710 (76.3%) 32,340 (73.3%) 33,460 (77.2%) 31,730 (73.2%) Hospital region P < 0.001 P = 0.75 Northeast 33,135 (14.8%) 8480 (19.2%) 8395 (19.4%) 8240 (19.0%) Midwest 46,315 (20.7%) 6840 (15.5%) 6980 (16.1%) 6790 (15.7%) South 99,975 (44.7%) 20,165 (45.7%) 20,000 (46.1%) 19,835 (45.8%) West 44,315 (19.8%) 8620 (19.5%) 7965 (18.4%) 8475 (19.6%) Primary expected payer P < 0.001 P < 0.001 Medicare 128,855 (57.7%) 25,360 (57.6%) 27,300 (63.1%) 24,975 (57.7%) Medicaid 35,000 (15.7%) 5995 (13.6%) 5830 (13.5%) 5850 (13.5%) Private insurance 40,745 (18.2%) 9120 (20.7%) 6780 (15.7%) 8955 (20.7%) Self-pay 10,745 (4.8%) 1585 (3.6%) 2005 (4.6%) 1555 (3.6%) Median household income P < 0.001 P = 0.52 0-25th percentile 75,500 (34.4%) 18,050 (41.6%) 18,090 (42.5%) 17,590 (41.3%) 26th-50th percentile 59,285 (27.0%) 11,235 (25.9%) 10,890 (25.6%) 11,055 (25.9%) 51st-75th percentile 47,640 (21.7%) 8660 (20.0%) 8350 (19.6%) 8550 (20.1%) 76th-100th percentile 36,995 (16.9%) 5460 (12.6%) 5265 (12.4%) 5445 (12.8%) Hospital bed size P < 0.001 P = 0.68 Small 44,830 (20.0%) 10,490 (23.8%) 9820 (23.0%) 10,045 (23.5%) Medium 67,315 (30.1%) 14,490 (32.9%) 14,280 (33.4%) 13,960 (32.7%) Large 111,595 (49.9%) 19,125 (43.4%) 18,615 (43.6%) 18,710 (43.8%) COPD, chronic obstructive pulmonary disease. Results A total of 267,845 hospitalizations for cardiac arrest were identified in the year 2020, with 44,105 patients (16.5%) having a concomitant diagnosis of COVID-19. The overall number of patients with cardiac arrest was higher in 2020 (n = 267,845) than in 2019 (n = 216,945). During 2020 the number of patients hospitalized with cardiac arrest and concomitant COVID-19 increased over time, with 3 distinct peaks (Fig 1 ).FIG 1 Trends in cardiac arrest hospitalizations with concomitant COVID-19. FIG 1 Baseline Characteristics Table 1 describes the baseline characteristics of patients admitted with cardiac arrest, with and without a concomitant diagnosis of COVID-19. Patients with cardiac arrest and concomitant COVID-19 were more likely to be older, male, African American, and Hispanic. There was a higher prevalence of cardiovascular comorbidities including diabetes mellitus, hypertension, chronic kidney disease, coagulopathy and obesity in patients with cardiac arrest and concomitant COVID-19 compared to those without COVID-19. However, the prevalence of congestive heart failure, peripheral vascular disorders, and cardiac arrhythmias were significantly lower. Patients with cardiac arrest and concomitant COVID-19 were more likely to have lower median household income. After propensity matching, there were 43,340 patients in each group, with no significant differences in baseline characteristics. (Table 1) Mortality There were significantly higher rates of in-hospital mortality in cardiac arrest patients with COVID-19 (87.0% vs 61.4%, P< 0.001) as shown in Table 2 . After propensity score matching, there were 43,340 patients in each group. In this propensity score-matched population, cardiac arrest patients with COVID-19 had a higher rate of in-hospital mortality compared with patients without COVID-19 (87% vs 64.5%, OR 3.67[95% CI: 3.38, 3.98] P < 0.001).TABLE 2 In-hospital outcomes of cardiac arrest hospitalizations stratified by COVID-19 Table 2 Pre-match cohort Post-match cohort No COVID-19 (n = 223,740) COVID-19 (n = 44,105) P value No COVID-19 (n = 43,340) COVID-19 (n = 43,340) P value In-hospital Mortality 137,390 (61.4%) 38,360 (87.0%) <0.001 27,955 (64.5%) 37,685 (87.0%) P < 0.001 Odds ratio 4.31 (4.00-4.64) <0.001 Ref. 3.67 (3.38-3.98) <0.001 Acute kidney injury 116,200 (51.9%) 28,695 (65.1%) <0.001 23415 (54.8%) 27710 (64.9%) <0.001 Odds ratio 1.66 (1.58-1.75) <0.001 Ref. 1.53 (1.44-1.62) <0.001 AKI leading to dialysis 15,705 (7.0%) 6175 (14.0%) <0.001 3515 (8.2%) 5930 (13.9%) <0.001 Odds ratio 2.04 (1.88-2.21) <0.001 Ref. 1.90 (1.72-2.11) <0.001 Sepsis 78,975 (35.3%) 26325 (59.7%) <0.001 17275 (40.4%) 25385 (59.4%) <0.001 Odds ratio 2.5 (2.43-2.74) <0.001 Ref. 2.23 (2.08-2.39) <0.001 Deep vein thrombosis 7375 (3.3%) 1735 (3.9%) <0.001 1330 (3.1%) 1690 (4.0%) <0.001 Odds ratio 1.25 (1.10-1.43) 0.001 Ref. 1.33 (1.12-1.58) 0.001 Pulmonary embolism 9795 (4.4%) 2095 (4.8%) 0.14 2210 (5.2%) 2050 (4.8%) 0.27 Odds ratio 1.17 (1.04-1.32) 0.008 Ref. 1.04 (0.90-1.21) 0.577 Stroke 6130 (2.7%) 470 (1.1%) <0.001 1385 (3.2%) 470 (1.1%) <0.001 Odds ratio 0.38 (0.31-0.47) <0.001 Ref. 0.36 (0.29-0.46) <0.001 Cardiogenic shock 15,950 (7.1%) 1400 (3.2%) <0.001 2300 (5.4%) 1380 (3.2%) <0.001 Odds ratio 0.45 (0.39-0.51) <0.001 Ref. 0.46 (0.40-0.53) <0.001 Ventricular tachycardia 34,290 (15.3%) 4170 (9.5%) <0.001 5010 (11.7%) 4115 (9.6%) <0.001 Odds ratio 0.59 (0.54-0.64) <0.001 Ref. 0.65 (0.58-0.71) <0.001 Ventricular fibrillation 35,020 (15.7%) 2915 (6.6%) <0.001 4615 (10.8%) 2855 (6.7%) <0.001 Odds ratio 0.41 (0.37-0.45) <0.001 Ref. 0.49 (0.44-0.54) <0.001 Vasopressor use 32,510 (14.5%) 6890 (15.6%) 0.05 6210 (14.5%) 6695 (15.7%) 0.07 Odds ratio 1.12 (1.03-1.22) 0.006 Ref. 1.09 (0.99-1.19) 0.088 Mechanical ventilation 31,895(68.1%) 152,445(72.3%) <0.001 30,275(69.9%) 31,280(72.2%) 0.0012 1.22 (1.15-1.30) <0.001 Ref. 1.12 (1.05-1.20) 0.001 Mechanical ventilation >24hours 96,730 (43.2%) 23,710 (53.8%) <0.001 19,070 (44.6%) 22,875 (53.6%) <0.001 Odds ratio 1.48 (1.41-1.57) <0.001 Ref. 1.41 (1.33-1.51) <0.001 Acute respiratory failure 162,860 (72.8%) 32,110 (72.8%) 0.98 31,285 (73.2%) 31,070 (72.7%) 0.52 Odds ratio 0.98 (0.92-1.05) 0.56 Ref. 0.93 (0.86-1.01) 0.065 VA-ECMO 1330 (0.6%) 105 (0.2%) <0.001 200 (0.5%) 105 (0.2%) <0.05 Odds ratio 0.58 (0.37-0.90) 0.015 Ref. 0.45 (0.26-0.77) 0.004 VV-ECMO 475 (0.2%) 345 (0.8%) <0.001 80 (0.2%) 340 (0.8%) <0.001 Odds ratio 5.20 (3.65-7.28) <0.001 Ref. 4.28 (2.42-7.55) <0.001 Impella 2330 (1.0%) 55 (0.1%) <0.001 335 (0.8%) 55 (0.1%) <0.001 Odds ratio 0.12 (0.07-0.22) <0.001 Ref. 0.13 (0.07-0.25) <0.001 IABP 3495 (1.6%) 90 (0.2%) <0.001 430 (1.0%) 90 (0.2%) <0.001 Odds ratio 0.12 (0.08-0.20) <0.001 Ref. 0.16 (0.10-0.26) <0.001 Targeted temperature management 3855 (1.7%) 605 (1.4%) <0.05 695 (1.6%) 595 (1.4%) 0.21 Odds ratio 0.86 (0.70-1.06) 0.158 Ref. 0.80 (0.62-1.04) 0.091 PCI 14,300 (6.4%) 370 (0.8%) <0.001 1740 (4.1%) 365 (0.9%) <0.001 Odds ratio 0.13 (0.10-0.16) <0.001 Ref. 0.19 (0.14-0.24) <0.001 ICD implantation 6355 (2.8%) 65 (0.1%) <0.001 635 (1.5%) 65 (0.2%) <0.001 Odds ratio 0.05 (0.03-0.09) <0.001 Ref. 0.07 (0.04-0.13) <0.001 Length of stay 8.9 (15.4) 12.9 (14.4) <0.001 8.7 (14.9) 12.9 (14.3) <0.001 Total cost 41,873 (78,353) 50,160 (69,023) <0.001 39,230 (63,164) 50,146 (69,470) <0.001 AKI, Acute kidney injury; VV, veno-venous; VA, veno arterial; ECMO, extracorporeal membrane oxygenation; PCI, percutaneous coronary intervention; ICD, implantable cardioverter defibrillator; IABP, intra aortic balloon pump; Ref., reference. Predictors of Mortality COVID-19 diagnosis was found to be an independent predictor of mortality in patients admitted with cardiac arrest (aOR 4.31 [95% CI 3.99, 4.64], P < 0.001). Among cardiac arrest patients with COVID-19, age (aOR per year of age 1.02 [95% CI 1.01,1.02], P < 0.001), female gender (aOR 1.09 [95% CI 1.06, 1.14], P < 0.001) diabetes mellitus (aOR 1.05 [95% CI 1.01, 1.1], P < 0.001), peripheral vascular disease (aOR 1.28[95% CI 1.11,1.26], P < 0.001), dementia [aOR 1.36 [95% CI 1.25,1.47] P < 0.001] and liver disease (aOR 1.53[95% CI 1.46, 1.61], P < 0.001) were found to be independently associated with increased odds of mortality on multivariate regression analysis (Fig 2 ).FIG 2 Independent predictors of mortality in patients admitted with cardiac arrest and concomitant COVID-19. FIG 2 Secondary Outcomes Cardiac arrest patients with COVID-19 were more likely to have acute kidney injury requiring dialysis, deep vein thrombosis and sepsis compared to those with cardiac arrest without COVID-19. COVID-19 patients were also more likely to have respiratory failure requiring mechanical ventilation as well as prolonged mechanical ventilation. There were significantly fewer patients in the COVID-19 group with cardiogenic shock, ventricular tachycardia, or ventricular fibrillation. (Table 2 and Fig 3 A)FIG 3 Outcomes of cardiac arrest Hospitalizations stratified by concomitant COVID-19. FIG 3 Cardiac arrest patients with COVID-19 were also less likely to undergo percutaneous coronary intervention (0.9% vs 4.1%, P < 0.001) or be treated with intra-aortic balloon pump (0.2% vs 1.0%, P < 0.001), Impella (0.1% vs 0.8%, P < 0.001), or veno-arterial ECMO (0.9% vs 4.1%, P < 0.001). Veno-venous ECMO use was higher in COVID-19 patients, (0.8% vs 0.2%, P < 0.001 respectively). Among the patients who survived to discharge, the rate of ICD implantation was lower in patients with COVID-19 (0.2% vs 1.5%, P < 0.001). (Fig 3B) Health Care Utilization Cardiac arrest patients with concomitant COVID-19 had longer length of stay (LOS) (median: 12.9 (14.3) days vs 8.7 (14.9) days; P < 0.001) and higher median cost of hospitalization costs ($50,146 (69,470)] vs $39,230 (63,164), respectively; P < 0.001) compared to patients without COVID-19. Discussion In a large population-based study, we report the characteristics and outcomes of hospitalizations for cardiac arrest associated with concomitant COVID-19 (Fig 4 : Central Illustration).FIG 4 Central illustration. FIG 4 An increase in out-of-hospital cardiac arrest has been reported during previous viral epidemics.10 This is in accordance with our current study, in which we noted a 23% increase in total cardiac arrests during 2020 compared to 2019. It has been hypothesized that this association is related to the impact of a systemic inflammatory response on the stability of atherosclerotic plaques, resulting in myocardial infarction and cardiac arrest.11 , 12 In addition, COVID-19 has been shown to cause endothelial injury, which can predispose to both arterial and venous thromboembolism and associated adverse outcomes.13 Further, previous reports have demonstrated that, during the pandemic, patients with acute cardiovascular diseases delayed care and avoided hospitals due to concerns over acquiring COVID-19.14 Further, detection of signs or symptoms that could have been harbingers of a cardiac arrest through outpatient clinic visits was likely adversely affected by the pandemic.15 The overall prevalence of COVID-19 in hospitalizations for cardiac arrest was 16.5% in 2020, with trends showing 3 distinct peaks. A French registry reported a COVID-19 prevalence of ∼8% in patients with out-of-hospital cardiac arrest.16 The higher prevalence of COVID-19 among cardiac arrest patients reported in the current study is likely related to our inclusion of in-hospital cardiac arrests, which were also more common during the COVID-19 pandemic.17 We found that COVID-19 was diagnosed more commonly among cardiac arrest patients who were African American or Hispanic, and in those with lower incomes. This finding likely reflects more general health-related disparities in the United States, stemming from a host of factors ranging from individual vulnerabilities to social and environmental influences. Such disparities have previously been reported with respect to multiple other aspects of the COVID-19 pandemic in the United States population.18, 19, 20 Outcomes were significantly worse among patients with cardiac arrest and concomitant COVID-19. In-hospital mortality for cardiac arrest with COVID-19 was 86.9% and was associated with a ∼3.67-fold higher odds of mortality compared to cardiac arrest without COVID-19. Prior reports have demonstrated similarly high mortality rates of more than ∼90% during the pandemic in cardiac arrest patients with COVID-19 infection.4 , 9 , 21 , 22 Further, there was a higher incidence of adverse outcomes such as AKI requiring dialysis and extended mechanical ventilation in cardiac arrest patients with COVID-19. Potential explanations include the fact that the COVID-19 pandemic resulted in a significant impact on the chain of survival such as early activation of emergency services, cardiopulmonary resuscitation (CPR), and defibrillation.3 Further, the concerns of contracting the virus during aerosol-generating procedures such as CPR and mechanical ventilation, as well as the need for personal protective equipment, could have adversely affected outcomes.23 Previous reports have demonstrated a delay and/or complexities in care due to sheer volume and immensely stretched resources during the peak of pandemic.2 , 24 Although the cause of cardiac arrest was not available in the NIS data set, several lines of evidence suggest that noncardiac causes may have been more common among those with concomitant COVID-19: the rates of cardiac complications such as cardiogenic shock and ventricular arrhythmias were significantly lower in patients with COVID-19; there was a lower utilization of cardiac procedures such as PCI, IABP, and Impella in those with COVID-19; and there was greater utilization of V-V ECMO and a lower utilization of V-A ECMO in the COVID-19 cohort. In addition, previous studies have demonstrated a lower incidence of shockable rhythms in patients with cardiac arrest occurring in patients with COVID-19 when compared to those without COVID-19, which also implies a greater burden of noncardiac causes of cardiac arrest in this population. As cardiac arrests from noncardiac causes tend to lead to higher mortality than those from cardiac causes, this likely explains at least a part of the higher mortality in COVID-19 patients.25 Our study has several limitations inherent to the administrative claim-based NIS database. Although such databases can be subject to misclassification errors, the HCUP-NIS attempts to mitigate potential errors by using vigorous internal and external quality control measures.26 We were not able to differentiate between out-of-hospital and in-hospital cardiac arrest, and these entities are known to have differential outcomes.27 By design our study is limited to patients who survived long enough to be hospitalized and thus does not account for the patients who died in the emergency department or outside the hospital. Conclusion There was a significant increase in cardiac arrest hospitalizations in 2020, the first year of the COVID-19 pandemic. During this time, patients hospitalized with cardiac arrest in the setting of concomitant COVID-19 had significantly worse outcomes, including mortality, when compared to patients without COVID-19. Potential explanations include adverse pathophysiologic effects of COVID-19, a higher prevalence of noncardiac etiology of cardiac arrest, and logistical challenges related to caring for patients with COVID-19. The authors have no conflicts of interest to disclose. ==== Refs References 1 WHO COVID-19 Dashboard. Geneva: World Health Organization, 2020. Available at: https://covid19.who.int/(last cited: [9/29/222]). 2 Nadarajah R Wu J Hurdus B The collateral damage of COVID-19 to cardiovascular services: A meta-analysis Eur Heart J 43 33 2022 3164 3178 36044988 3 Uy-Evanado A Chugh Harpriya S Sargsyan A Out-of-hospital cardiac arrest response and outcomes during the COVID-19 pandemic JACC: Clin Electrophysiol 7 1 2021 6 11 33478713 4 Chan PS Girotra S Tang Y Outcomes for out-of-hospital cardiac arrest in the United States during the coronavirus disease 2019 pandemic JAMA Cardiol 6 3 2021 296 303 33188678 5 Lai PH Lancet EA Weiden MD Characteristics associated with out-of-hospital cardiac arrests and resuscitations during the novel Coronavirus Disease 2019 pandemic in New York City JAMA Cardiol 5 10 2020 1154 1163 32558876 6 Marijon E Karam N Jost D Out-of-hospital cardiac arrest during the COVID-19 pandemic in Paris, France: A population-based, observational study Lancet Public Health 5 8 2020 e437 e443 32473113 7 Fugate JE Brinjikji W Mandrekar JN Post-cardiac arrest mortality is declining: A study of the US National Inpatient Sample 2001 to 2009 Circulation 126 5 2012 546 550 22740113 8 Merchant RM Topjian AA Panchal AR Part 1: executive summary: 2020 American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care Circulation 142 16_suppl_2 2020 S337 S357 33081530 9 Teoh SE Masuda Y Tan DJH Impact of the COVID-19 pandemic on the epidemiology of out-of-hospital cardiac arrest: A systematic review and meta-analysis Ann Intensive Care 11 1 2021 169 34874498 10 Suematsu Y Kuwano T Yamashita M Adult influenza epidemic is associated with out-of-hospital cardiac arrest: From the All-Japan Utstein Registry, a prospective, nationwide, population-based, observational registry Medicine (Baltimore) 101 24 2022 e29535 35713463 11 Nguyen JL Yang W Ito K Seasonal influenza infections and cardiovascular disease mortality JAMA Cardiol 1 3 2016 274 281 27438105 12 Madjid M Miller CC Zarubaev VV Influenza epidemics and acute respiratory disease activity are associated with a surge in autopsy-confirmed coronary heart disease death: results from 8 years of autopsies in 34 892 subjects Eur Heart J 28 10 2007 1205 1210 17440221 13 Bandyopadhyay D Akhtar T Hajra A COVID-19 Pandemic: Cardiovascular complications and future implications Am J Cardiovasc Drugs 20 4 2020 311 324 32578167 14 De Rosa S Spaccarotella C Basso C Reduction of hospitalizations for myocardial infarction in Italy in the COVID-19 era Eur Heart J 41 22 2020 2083 2088 32412631 15 Dupraz J Le Pogam M-A Peytremann-Bridevaux I Early impact of the COVID-19 pandemic on in-person outpatient care utilisation: A rapid review BMJ Open 12 3 2022 e056086 16 Baert V Beuscart JB Recher M Coronavirus disease 2019 and out-of-hospital cardiac arrest: No survivors Crit Care Med 50 5 2022 791 798 34605777 17 Girotra S Chan ML Starks MA Association of COVID-19 infection with survival after in-hospital cardiac arrest among US adults JAMA Net Open 5 3 2022 e220752 18 Abedi V Olulana O Avula V Racial, economic, and health inequality and COVID-19 infection in the United States J Racial Ethn Health Disparit 8 3 2021 732 742 19 Alcendor DJ. Racial disparities-associated COVID-19 mortality among minority populations in the US J Clin Med 9 8 2020 2442 32751633 20 Golestaneh L Neugarten J Fisher M The association of race and COVID-19 mortality EClinicalMedicine 25 2020 100455 21 Sultanian P Lundgren P Strömsöe A Cardiac arrest in COVID-19: Characteristics and outcomes of in- and out-of-hospital cardiac arrest. A report from the Swedish registry for cardiopulmonary resuscitation Eur Heart J 42 11 2021 1094 1106 33543259 22 Lim ZJ Ponnapa Reddy M Afroz A Incidence and outcome of out-of-hospital cardiac arrests in the COVID-19 era: A systematic review and meta-analysis Resuscitation 157 2020 248 258 33137418 23 Baert V Jaeger D Hubert H Assessment of changes in cardiopulmonary resuscitation practices and outcomes on 1005 victims of out-of-hospital cardiac arrest during the COVID-19 outbreak: registry-based study Scand J Trauma, Resusc Emerg Med 28 1 2020 1 10 31900203 24 Guddeti RR Yildiz M Nayak KR Impact of COVID-19 on acute myocardial infarction care Cardiol Clin 40 3 2022 345 353 35851458 25 Sasson C Rogers MA Dahl J Predictors of survival from out-of-hospital cardiac arrest: A systematic review and meta-analysis Circ: Cardiovasc Qual Outcomes 3 1 2010 63 81 20123673 26 HCUP QUALITY CONTROL PROCEDURES. (https://www.hcup-us.ahrq.gov/db/quality.jsp#procedures). 27 Høybye M Stankovic N Holmberg M In-Hospital vs. out-of-hospital cardiac arrest: Patient characteristics and survival Resuscitation 158 2021 157 165 33221361
PMC010xxxxxx/PMC10060010.txt	==== Front J Am Acad Dermatol J Am Acad Dermatol Journal of the American Academy of Dermatology 0190-9622 1097-6787 by the American Academy of Dermatology, Inc. S0190-9622(23)00519-4 10.1016/j.jaad.2023.03.031 Research Letter Association of herpes zoster with COVID-19 vaccination: A systematic review and meta-analysis Chen I-Ling MD a Chiu Hsien-Yi MD, PhD bcde∗ a Departments of Family Medicine, National Taiwan University Hospital Hsin-Chu Branch, Taiwan b Department of Medical Research, National Taiwan University Hospital Hsin-Chu Branch, Taiwan c Department of Dermatology, National Taiwan University Hospital Hsin-Chu Branch, Taiwan d Department of Dermatology, National Taiwan University Hospital, Taipei, Taiwan e Department of Dermatology, College of Medicine, National Taiwan University, Taipei, Taiwan ∗ Correspondence to: Hsien-Yi Chiu, MD, PhD, Department of Dermatology, National Taiwan University Hospital Hsin-Chu Branch, Taiwan, NO. 25, Lane 442, Sec. 1, Jingguo Rd, Hsinchu City 300, Taiwan (R.O.C.) 30 3 2023 30 3 2023 © 2023 by the American Academy of Dermatology, Inc. 2023 American Academy of Dermatology, Inc. Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Key words herpes zoster shingles COVID-19 COVID-19 vaccines meta-analysis ==== Body pmcTo the Editor: Herpes zoster (HZ), which is reactivation of the varicella zoster virus (VZV), is associated with older age, use of immunomodulatory drugs, trauma, family history, and other comorbidities.1 Moreover, case studies have reported development of HZ following administration of vaccinations against influenza, Japanese encephalitis, hepatitis A, and rabies.2 Recently, several cases of HZ after COVID-19 vaccinations have been reported1; however, the association remains a matter of debate due to the small number of cases and lack of control groups. We performed a systematic search within PubMed, EMBASE, and Web of Science for relevant publications from inception to November 2022 following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The protocol was registered in PROSPERO (CRD42023381589). Cohort studies, case-control cross-sectional studies, and randomized controlled trials reporting HZ outcomes in patients receiving COVID-19 vaccinations and control subjects were included. Studies with overlapping cases, lack of HZ outcomes, incomplete data, and case studies without controls were excluded (Supplementary Fig 1, available via Mendeley at https://data.mendeley.com/datasets/6jg7jkn65r/1). This meta-analysis (MA) used a random-effects model to calculate the pooled odds ratios (ORs) and 95% CIs to determine the risk of HZ in the COVID-19 vaccination group versus control groups. Subgroup analyses comparing the risk of HZ in the mRNA versus adenovirus vaccination groups and Moderna versus BioNTech vaccination groups were performed. Sixteen studies were included from initially identified 465 articles (Supplementary Table I, available via Mendeley at https://data.mendeley.com/datasets/6jg7jkn65r/1). COVID-19 vaccination was associated with a significantly increased risk of HZ (OR, 1.32; 95% CI, 1.09-1.62, P = .006) compared with controls (Supplementary Fig 2, available via Mendeley at https://data.mendeley.com/datasets/6jg7jkn65r/1). In subgroup analysis, the mRNA vaccination was associated with a higher risk of HZ compared with the adenovirus vaccination (OR, 1.67; 95% CI, 1.19-2.35, P = .003) (Supplementary Fig 3, available via Mendeley at https://data.mendeley.com/datasets/6jg7jkn65r/1). Further MA of studies comparing different brands of COVID-19 vaccinations showed no significant difference of HZ risks between Moderna and BioNTech (OR, 0.64; 95% CI, 0.18-2.21) (Supplementary Fig 4, available via Mendeley at https://data.mendeley.com/datasets/6jg7jkn65r/1). The mechanism underlying the link between COVID-19 vaccination and HZ remains elusive; however, vaccination-induced immunomodulation has been proposed. Vaccine-induced massive shift of CD8+ T cells and CD4+ helper T cells may cause temporary inability to suppress latent VZV, allowing for its reactivation.3 Previous studies indicate that immunocompromised status and older age are associated with a higher risk of VZV reactivations after vaccination.4 The reported median time to onset of HZ after COVID-19 vaccination was 7 to 10 days (range, 2-51 days).1 , 4 , 5 Although most cases of VZV reactivations were dermatome-limited, 2 cases of HZ infection after COVID-19 mRNA vaccination were disseminated.5 Our research has limitations. First, because most randomized controlled trials of COVID-19 vaccination did not report HZ as a separate individual adverse effect, the number of randomized controlled trials included in this MA is quite limited. Second, heterogeneity exists among the included studies, and the quality of the included studies is not very high (Supplementary Fig 5, available via Mendeley at https://data.mendeley.com/datasets/6jg7jkn65r/1). Nevertheless, our MA suggests an increased risk of HZ in patients receiving COVID-19 vaccination, and the mRNA vaccination is associated with a higher risk of HZ than the adenovirus vaccination. This highlights the awareness of possible reactivation of HZ following COVID-19 vaccination, particularly for high-risk individuals. Conflicts of interest H.Y.C. received speaking fees from AbbVie, Novartis Pharmaceuticals Corporation, Janssen-Cilag Pharmaceutica, Eli-Lilly, Kyowa Hakko Kirin Taiwan, and Pfizer Limited and conducted clinical trials for Eli-Lilly, AbbVie, and Sanofi Pharmaceuticals. I.L.C. has no conflicts of interest to declare. We thank the staff of Department of Medical Research, National Taiwan University Hospital Hsin-Chu Branch for their assistance in study design, statistical analysis, and providing careful review and insightful comments regarding the articles. Funding sources: This work was funded in part by grants from National Taiwan University Hospital, Hsin-Chu branch (112-HCH092, 112-HCH065) and Taiwan Ministry of Science and Technology (MOST 111-2314-B-002-244). The funders had no role in the study design, data collection and analysis, interpretation of findings, manuscript writing, or target journal selection. IRB approval status: Not applicable. Reprints not available from the authors. ==== Refs References 1 Rodríguez-Jiménez P. Chicharro P. Cabrera L.M. Varicella-zoster virus reactivation after SARS-CoV-2 BNT162b2 mRNA vaccination: report of 5 cases JAAD Case Rep 12 2021 58 59 33937467 2 Walter R. Hartmann K. Fleisch F. Reinhart W.H. Kuhn M. Reactivation of herpesvirus infections after vaccinations? Lancet 353 9155 1999 810 3 Psichogiou M. Samarkos M. Mikos N. Hatzakis A. Reactivation of varicella zoster virus after vaccination for SARS-CoV-2 Vaccines (Basel) 9 6 2021 572 34205861 4 Préta L.H. Contejean A. Salvo F. Treluyer J.M. Charlier C. Chouchana L. Association study between herpes zoster reporting and mRNA COVID-19 vaccines (BNT162b2 and mRNA-1273) Br J Clin Pharmacol 88 7 2022 3529 3534 35174524 5 Said J.T. Virgen C.A. Lian C.G. Cutler C.S. Merola J.F. LeBoeuf N.R. Disseminated varicella-zoster virus infections following messenger RNA-based COVID-19 vaccination JAAD Case Rep 17 2021 126 129 34568532
PMC010xxxxxx/PMC10060133.txt	==== Front Curr Nutr Rep Curr Nutr Rep Current Nutrition Reports 2161-3311 Springer US New York 36991238 464 10.1007/s13668-023-00464-1 Review Synbiotics and Surgery: Can Prebiotics and Probiotics Affect Inflammatory Surgical Outcomes? Trone Kristin [email protected] 1 Rahman Shahrose 1 Green Caitlin Homberger 2 Venegas Carla 3 Martindale Robert 1 Stroud Andrea 1 1 grid.5288.7 0000 0000 9758 5690 OHSU, 3181 S.W. Sam Jackson Park Rd., Mail Code: L223, Portland, OR 97239 USA 2 grid.259828.c 0000 0001 2189 3475 MUSC, Charleston, USA 3 Mayo, FL USA 30 3 2023 2023 12 2 238246 7 2 2023 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Purpose of Review Prebiotics, probiotics, and synbiotics have received increasing attention over the years for their beneficial impact on the gut microbiome and for their systemic anti-inflammatory effects. They have also been shown to improve surgical outcomes. Here, we review the inflammatory effects of surgery as well as the data which suggests a benefit of prebiotics, probiotics, and synbiotics taken in the perioperative period. Recent Findings Synbiotics and fermented foods may have an even greater anti-inflammatory effect than probiotics or prebiotics alone. Recent data suggest that the anti-inflammatory effects and microbiome changes brought on by prebiotics, probiotics, and synbiotics have the potential to improve surgical outcomes. We highlight the potential to alter systemic inflammation, surgical and hospital-acquired infections, colorectal cancer formation, recurrence, and anastomotic leak. Synbiotics could also impact metabolic syndrome. Summary Prebiotics, probiotics, and especially synbiotics may be extremely beneficial when taken in the perioperative period. Even short-term gut microbiome pre-habilitation could alter surgical outcomes significantly. Keywords Synbiotics Fermented foods Surgical outcomes Surgical site infections Inflammation issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction For many years, there has been increasing interest in the study of the gut microbiome. In 1992, probiotics were defined as “a preparation of or a product containing viable, defined microorganisms in sufficient numbers, which alter the microflora (by implantation or colonization) in a compartment of the host and by that exert beneficial health effects in this host” [1]. In more recent years, interest has turned to prebiotics, or “non-digestible food ingredients (fiber) that beneficially affect the host by selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon” [1]. These bacteria transform the fiber into short chain fatty acids which exert beneficial local and systemic effects [2]. The gut microbiome is dynamic and can be transformed quickly by supplements containing bacteria (probiotics) or fiber (prebiotics). In fact, a change in the amount of fiber in a diet can alter the composition of the microbiome in as little as 24 h [3]. Synbiotics, often in the form of fermented foods, combine prebiotics and probiotics, which act synergistically. In a 2012 study comparing a synbiotic supplement to a prebiotic, the synbiotics decreased circulating levels of interleukin (IL)-16 by approximately 50%, compared with the single prebiotic alone [4]. Among other effects, prebiotics, probiotics, and synbiotics act as anti-inflammatory supplements with the latter perhaps being the most effective. Because surgery has a clear inflammatory effect on the body [5], in this review, we explore the ways in which prebiotics, probiotics, and synbiotics may play a role in modulating the immune response in the perioperative period, and the extent to which they may affect surgical outcomes. Inflammation Inflammation, although required for the normal response to invading organisms and stress, when excessive and uncontrolled can precipitate a variety of chronic diseases and subdues healing in many forms. Inflammatory syndromes which fail to resolve can lead to dysfunction in a wide range of organ systems including vascular disease, metabolic syndrome, multiple gastrointestinal conditions, and neurologic diseases. In addition, unresolved inflammation can even lead to neoplastic disease, which is well understood in the case of chronic liver disease and hepatocellular carcinoma. Appropriate inflammatory signaling is vital to immune system function and excessive inflammation is detrimental to healing from surgical and medical diseases. Tissue injury from surgery initially promotes an inflammatory state. The body’s immediate response to surgery is the upregulation of the innate immune system, eliciting a furor of neutrophils, monocytes, and cytokines including IL-1β, IL-6, and tumor necrosis factor α (TNF-α). The goal of upregulation of the innate immune system is to target infection, limit tissue damage, and eliminate destroyed cells in order to promote healing [6, 7]. This initial inflammatory state triggers suppression of the adaptive immune system by dampening T cell proliferation in order to quell a hyper-inflammatory response which may hinder appropriate healing [5, 8]. The anti-inflammatory phase is prolonged in comparison to the initial heightened innate immune response and is associated with increased levels of anti-inflammatory cytokines including IL-1, IL-4, and IL-10, and bioactive lipids [6, 9]. Immune system stability is important for healing from surgery and disease, and a swing too far in either direction can lead to immune dysfunction and suppression. On one hand, hyper-inflammation defined by elevated inflammatory markers can lead to suppressed immunity. This is evidenced by recent data from the COVID-19 pandemic suggesting that elevated inflammatory markers correspond with more severe disease and worse outcomes [10]. Suppression of the adaptive immune system as seen in the delayed anti-inflammatory response to surgery can put the postoperative patient in an immunosuppressed state as well, and at risk for sepsis and even multi-system organ failure [5]. The immune system is a complex web of pathways modulated by ON/OFF signaling molecules. A paucity or overabundance of any one of these molecules may cause extreme effects downstream. In the context of post-surgical healing, there is scarcity of data directly linking levels of specific inflammatory molecules with specific surgical outcomes, but the need to avoid abundant inflammation is clear. For example, elevated inflammatory cytokines have been linked to postoperative delirium, excessive muscle catabolism, and prolonged hospital and ICU stays [11–13]. Cytokines may increase the permeability of the blood brain barrier and act on the hippocampus causing delirium and cognitive decline [13]. In colorectal cancer, high levels of inflammatory cytokines have been shown to promote malignant progression and recurrence after surgery [14]. Inflammation also compromises the mucosal barrier. This is pertinent to surgery as a compromised mucosal barrier exacerbates systemic inflammation secondary to bacterial metabolites, fragments, and possibly even intact bacteria getting into the systemic circulation [15]. There is evidence that prebiotics, probiotics, and synbiotics help enhance the mucosal barrier by several mechanisms [16]. If keeping inflammation at bay is the goal, one might ask what can be done to modulate the immune response? Consistent use of synbiotics, prebiotics, and probiotics has the potential to change our inflammatory status and may have implications in the perioperative period. In a recent study, 52 patients with colorectal cancer were given either a placebo or a probiotic supplement containing lactobacillus and bifidobacterium for 6 months after surgery. Patients in the probiotic group were found to have a significant reduction in levels of pro-inflammatory cytokines TNF-α, IL-6, IL-10, IL-12, IL-17A, IL-17C, and IL-22 [17]. In this study, Zaharuddin et al. observe that that IL-10 and IL-12 have somewhat of a dual functionality as anti-inflammatory and pro-inflammatory cytokines, but the study did not find a significant increase in uniquely pro-inflammatory cytokines with the use of probiotics. The mechanism by which lactic acid producing bacteria (as in the Zaharuddin et al. study) exert an anti-inflammatory effect is unknown, although recent studies have elucidated possibilities. One example might be the activation of the vitamin D receptor autophagy signaling pathway [18], a pathway that may be associated with levels of IL-6 and other inflammatory cytokines [19]. There is also evidence that probiotics may affect inflammatory cytokine levels by acting on the NF-κB and MAPK signaling pathways [20, 21]. Of course, this is probably just the tip of the iceberg; mechanisms could be numerous and mixed and likely vary by species or even genus of bacteria. Prebiotics have also been implicated in several different anti-inflammatory pathways. These include reduction of pro-inflammatory cytokines and macrophages as well as the increase of regulatory T cells and anti-inflammatory cytokines [22–24]. Fermented foods are synbiotics which are often high in both prebiotics and probiotics, thus providing the immune modulating benefits of both groups. In fact, fermented foods may be a powerful tool to improve human health. In a recent study, Wastyk et al. randomized 36 adults to either a high fiber arm or a high fermented foods arm [25•]. Participants in the high fermented food arm consumed an average of 0.4 ± 0.6 servings per day of fermented food at baseline, which increased to an average of 6.3 ± 2.9 servings per day during the study. Yogurt and vegetable brine drinks were consumed at higher rates relative to the other types of fermented foods. These two fermented foods are largely products of lactic acid fermentation, with analogous benefit to the lactic acid-producing bacteria administered in the colorectal cancer trial discussed above [17]. Wastyk et al. reported that microbiome alpha diversity (different types of bacteria) was significantly increased in the fermented food group, including new variants that were not present before the intervention. Microbial diversity has been correlated with human health [26, 27]. Although 90% of the bacteria in our microbiomes belong to just 20 species, the human microbiome has > 2300 species of bacteria that have been sequence [28]. The Wastyk et al. study demonstrates that in addition to an increase in microbiome diversity and introduction of new varieties of bacteria, several inflammatory markers decreased over the fermented food intervention, including IL-6, IL-10, and IL-12b [24]. These data support the anti-inflammatory findings of the probiotic and prebiotic data previously discussed and implicate fermented foods as a possible regulator of inflammation. Beyond just reducing circulating levels of inflammatory markers in the blood, recent data utilizing a murine model demonstrate that kefir, a fermented milk synbiotic, alleviates tissue injury. In this study, mice were exposed to particulate matter by endotracheal instillation in order to induce pulmonary inflammation, oxidative stress, and overexpression of inflammatory markers. The lung tissue of the mice that were fed kefir had a reduction in oxidative stress and local inflammatory cell infiltration [20]. These data suggest that synbiotics may provide a systemic tissue healing benefit beyond the benefit to the local GI mucosa alone. Although much of these data refer to the separate components, either prebiotics or probiotics, it does seem that the combination in the form of synbiotics and fermented foods may be of greater benefit than each component on its own. The anti-inflammatory nature of synbiotics provide an exciting potential therapeutic option to improve surgical outcomes. Surgical and Hospital-Acquired Infection Surgical site infection (SSI) is a potentially preventable cause of postoperative patient morbidity, and its occurrence contributes to increased healthcare costs. It is the leading cause of hospital readmission after surgery, approaching 20% of overall readmissions [29]. Surgeons and healthcare systems have increasingly focused on decreasing SSI rates through quality improvement initiatives and infection prevention bundles [30]. However, recent evidence has questioned the standard dogma that SSI results from intraoperative local contamination, but rather points to pathogens originating from sites remote from the operative wound [31]. Evidence against these long-held beliefs include studies demonstrating that > 80% of wounds with positive intraoperative cultures do not develop an SSI and wound cultures at the time of operation show no correlation with pathogens involved in the SSI [31]. Alverdy and colleagues have proposed a theory, termed the Trojan Horse hypothesis, whereby bacteria from the oral cavity or gastrointestinal tract can be taken up by immune cells and travel to the wound site, where they ultimately can cause an SSI [32]. Their team has been able to demonstrate this theory in a mouse model with fluorescence-labeled bacteria [32]. Given the above, is there a potential to alter the resident human oral and gastrointestinal microbiome to decrease wound infections following surgery? As already discussed in this review, administration of synbiotics can manipulate the composition of the gastrointestinal flora. Several randomized controlled trials (RCT) have employed synbiotics in abdominal surgery, with some trials demonstrating no difference when compared to placebo [33–35], but with the majority of studies demonstrating a benefit of synbiotics [36–45]. The trials have employed heterogeneous interventions, including probiotics only, probiotics plus fibers, and probiotics plus tube feeding containing fiber as well as various timing strategies with administration before, after, or both before and after surgery. Some trials have aimed to explore mechanisms, and many report effects on levels of inflammatory markers, as previously described, or on a decrease in pathogenic colonic bacteria (ref). Additionally, these trials have been combined as systematic review and meta-analysis, with the conclusion that synbiotics, specifically both before and after surgery, have the potential to reduce infectious complications significantly [46–49]. In the most recently published systematic review, including only RCT, there was an almost 50% reduction in postoperative infectious complications (RR 0.56, 95% CI 0.46–0.69; P < 0.00001, I2 = 42%) [46]. Finally, investigators in Japan have shown that perioperative oral care (professional oral care and oral self-care instruction) resulted in decreased risk of SSI compared to a control group (8.4 vs 15.7%, P < 0.001) [50]. Current meta-analysis suggests that synbiotics may also reduce the rate of respiratory, urinary tract, and wound infection complications following gastrointestinal surgery, in addition to shortening the length of hospital stay and antibiotic therapy, with no direct impact on mortality [51–57]. Newer data suggest that the use of preoperative plus postoperative synbiotics is more effective compared with only postoperative synbiotics or placebo, significantly reducing the incidence of infections, with less hospital stay and length of antibiotic usage [46, 58]. Synbiotics have also been associated with a greater benefit in reducing the incidence of VAP (RR 0.50, 95% CI 0.32–0.79) when compared to probiotics (RR 0.77, 95% CI 0.63–0.96) (P = 0.09) [51]: lower requirement for prokinetics, higher tolerance for tube feed administration, and decreased gastric residual volume (all P < 0/05) in critically ill patients [59]. Taken together, these data suggest that there is a potential benefit to perioperative administration of synbiotics for multiple types of abdominal surgery to decrease infectious complications. Administration both before and after surgery achieves the greatest benefit. Synbiotics are a relatively inexpensive intervention, which could result in fewer patients experiencing surgical infections and decreased healthcare costs. Results must be interpreted with caution as there is significant heterogeneity between studies and potential publication bias. Future studies should consider strain-specific evaluations to determine optimal formulations and consider ideal timing of the intervention. Colorectal Surgery as a Model System for Host-Microbiome Interactions Cancer Recurrence and Polyp Formation Colorectal cancer is associated with advancing age, genetics, and environmental conditions, including dietary factors, smoking history, physical activity, antibiotic exposure, and alterations in the intestinal microbiome [60, 61]. Increasing research on the intestinal microbiome has identified a relationship between intestinal microbial dysbiosis, colon polyps, and colorectal cancer. Further understanding of how intestinal dysbiosis contributes to tumorigenesis may reveal ways to augment the microbiome to improve colon health. Adenoma Formation Studies of the intestinal microbiome at the pre-neoplastic stage shed light on its relationship with the development of adenomas and progression to colorectal cancer. Recent evidence indicates that individuals with colorectal adenomas have distinctive microbiomes [62]. Watson et al. prospectively examined the microbiome of 104 individuals undergoing screening colonoscopies. Individuals were divided into adenoma and non-adenoma formers and oral, fecal, and mucosal microbiome samples were compared. They found that oral, fecal, and mucosal microbiomes are distinct. Specifically, they found that mucosal microbial abundances of adenoma formers have unique profiles, including specific taxa, that can reliably predict adenoma formation. Notably, oral and fecal abundances were not predictive of adenoma formation, suggesting that studies relying on fecal microbiome alone may be insufficient to characterize the intestinal microbiome, at least regarding adenoma formation. Colorectal Cancer Recurrence Despite advances in treatment, colorectal cancer recurs in up to 38% of patients who were designated to have undergone a curable resection [63, 64]. Much of the focus on recurrence has been attributed to factors inherent to the tumor, including grade, stage, lymphovascular invasion, presence of obstruction or perforation, and post-residual tumor status after resection [65]. However, there is mounting evidence for the role of the intestinal microbiome in both colorectal cancer development and recurrence. Diet is well established as a factor in the intestinal microbiome composition and is further linked to colorectal cancer recurrence by evidence that individuals consuming a Western diet (WD), or a diet high in fat and low in fiber and prebiotics, have a higher risk of colorectal cancer recurrence [66]. Gaines et al. used a murine model to demonstrate that a WD promoted collagenolytic organisms and contribute to tumor formation after colorectal surgery [67•]. Mice were fed a WD versus standard diet (SD) for 4 weeks prior to surgery. Mice were given pre-operative antibiotics and underwent colon resection and anastomosis. Mice were given an enterococcus faecalis enema on post-operative day (POD) 1, followed by an enema of colon carcinoma cells on POD 2. Upon examining feces and colons on day 21, 88% of WD fed mice had peri-anastomotic tumors versus 30% of SD mice. Interestingly, tumor formation correlated with presence of collagenolytic Enterococcus faecalis and Proteus mirabilis, such that WD mice had threefold higher colonization. This experiment also employed a novel therapy, ± Pi-PEG, a non-absorbable polyphosphate that suppresses bacterial collagenase. In addition to antibiotics, Pi-PEG was provided in the drinking water of some mice. The investigators found that while antibiotics eliminated collagenolytic bacteria, they did not prevent tumor formation and, in fact, promoted emergence of collagenolytic candida parapsilosis. Conversely, WD fed mice given antibiotics, E. faecalis and Pi-PEG, had a statistically significant 57% reduction in tumor formation and maintained microbial diversity compared with control WD fed mice without Pi-PEG [67•]. It has been demonstrated that adenoma formers have distinct mucosal microbiomes. Additionally, the evidence indicates that antibiotics, and dietary factors, specifically high fat and low fiber diet, induce intestinal dysbiosis and in certain instances promote microbes that disrupt anastomoses and contribute to colorectal cancer recurrence. Further understanding of these influences on the intestinal microbiome has the potential to impact outcomes related to colon polyps and colorectal cancer. Anastomotic Leak The reported rates of anastomotic leak (AL) vary between 1 and 19% in published data [68, 69]. Historically, tension, tissue perfusion, patient nutrition, and technique of anastomosis (stapled versus handsewn) are frequently investigated for causes of leaks. As our knowledge of the gut microbiome has increased, so too has our understanding of its effects on outcomes following gastrointestinal surgery and the major role it may play in anastomotic healing. Anastomotic leaks are strongly associated with local colorectal cancer recurrence [70], and anastomotic environment seems to play a similarly important role in both cases. Since bacteria colonize the mucosal surface of the bowel, the role of the mucosa should not be underappreciated when considering anastomotic leak. The resident microbial populations define the immune cells responsible for wound healing, such as the presence of M2 anti-inflammatory or “resolution” macrophages [71, 72]. Additionally, our current understanding is that the submucosa is composed of collagen and elastin, which provide the greatest tensile strength of all four layers of the bowel wall [73, 74]. Alverdy and colleagues again used a murine model to demonstrate that local microbial dysbiosis contributes to adverse surgical outcomes. They found that high abundances of Enterococcus faecalis and Pseudomonas aeruginosa play a critical role in the development of AL [75, 76]. In a mouse model, these bacteria contribute to AL’s through collagen lysis by high collagenase activity and activation of matrix metalloprotease-9, which further degrades collagen [77]. The discovery of Enterococcus faecalis and protease activation is notable as this is the most common pathogen isolated in AL in humans [76, 78]. Both colorectal cancer recurrence and anastomotic leak are affected by collagenolytic bacteria in the anastomotic environment [67•, 75, 76]. These findings raise the possibility of targeting the gut microbiome to prevent AL. If the abundance and diversity of beneficial bacteria can be increased while reducing the abundance of those that promote collagen lysis, perhaps this can result in a strategy to reduce AL, though future mechanistic studies are needed. Hyoju et al. demonstrated in a murine model that anastomotic healing was improved in mice who were fed a low-fat/high fiber diet compared to mice fed with a WD. This group again found an increase in abundance of Enterococcus faecalis in both the lumen and stool in the WD group, which we have seen is collagenolytic [79]. In the case of both colorectal cancer recurrence and anastomotic leak, prebiotic pre-habilitation in murine models has shown to improve outcomes by altering the local microbiome [67•, 79]. Human studies have revealed mixed if not incomplete findings. The COLON study examined the association between habitual fiber intake and risk of complications after surgery for colorectal cancer in 1399 patients. Of the 1237 patients who had an anastomosis, 5% experienced an AL. Interestingly, higher dietary fiber intake was associated with a lower risk of any complication, defined as cardiopulmonary complication, surgical site infection (SSI), or post-operative ileus [80]. However, no association was found with AL [80]. In a randomized, double-blind, placebo-controlled study performed by Kotzampassi et al., patients undergoing colorectal surgery either received capsules of placebo or a four-strain probiotic formulation 1 day before surgery and continued for 15 days post-operatively. Of the 84 patients in the probiotics group, 1.2% developed an AL compared to 8.8% of the 80 patients in the placebo group. These findings were statistically significant, and the study was prematurely stopped due to the high efficacy of the treatment [81]. In addition, Veziant et al. performed a systematic review in 2022 analyzing 21 randomized control trials where 15 trials included probiotics and 6 evaluated synbiotics in patients undergoing colorectal surgery. While the pooled data did demonstrate significantly fewer infectious complications and SSI’s, there was no difference seen for anastomotic leaks [82]. When analyzing the studies included, the studies varied in the timing of when the synbiotics/probiotics were given, there was heterogeneity in the formulations used, and doses varied. Overall, the data linking the gut microbiome to AL are compelling though incomplete. While the exact physiology and mechanism underlying its association remain unknown, both Alverdy and the more recent clinical data are impressive. There appears to be a changing paradigm in the causal factors of AL and SSI, and microbiome-altering supplements may be a solution. More research using evidence-based synbiotic formulations is needed prior to widespread implementation. Metabolic Syndrome Epidemiologic data over the past few decades have shown that the host microbiome plays a crucial role in human health, including affecting the determinants of metabolic syndrome. This includes links to obesity, type 2 diabetes mellitus, cardiovascular disease, liver disease, and malnutrition. The increased risk for adverse surgical outcomes in patients with metabolic syndrome is well established. This suggests that altering the microbiome may be a powerful means to prevent adverse surgical outcomes related to metabolic disease by improving the physiologic response inherent with these comorbidities. Patients with metabolic syndrome who undergo surgery have higher rates of death, cardiovascular events, coma, stroke, renal failure, and surgical site infections [83]. In addition to worse outcomes, these patients also experience prolonged hospitalizations, incur higher health service costs, and require more post-hospitalization care [84]. Although it is not realistic to alter the course of chronic diseases preoperatively, targeting the gut microbiome through dietary pre-habilitation may improve the immunologic response to surgery. Alverdy et al. have found in various murine models that intestinal microbiota are altered and surgical outcomes are improved even with a short duration high fiber pre-habilitation diet when compared to a WD arm [67•, 79, 85•]. In addition, there is evidence in human studies which link the composition of the gut microbiome to metabolic syndrome. Data have shown that the composition of the gut microbiota differ between lean and obese individuals. For example, Tims et al. performed a study profiling the gut microbiome in monozygotic twins discordant for obesity and found that the species Eubacterium ventriosum and Roseburia intestinalis were positively correlated with higher BMI [86]. These species are associated with more direct butyrate production, as opposed to scavenging of fermentation products to form butyrate, which may negatively affect host energy harvest [86]. Evidence suggests the gut microbiome can affect host gene expression by altering the metabolic and inflammatory pathways along the gut-brain axis [87]. Vrieze et al. administered the microbiota from lean individuals into the small intestine of men with metabolic syndrome. After 6 weeks, insulin sensitivity increased in the recipients, where the rate of median glucose disappearance increased from 26.2 to 45.3 μmol/kg/min [88]. We see that the gut microbiome can impact determinants of metabolic syndrome, and metabolic syndrome leads to negative surgical outcomes. This begs the question, could microbiome-directed interventions in the form of synbiotics improve surgical outcomes? For example, studies using synbiotics in the form of fermented foods have shown improvements in certain markers of metabolic syndrome. Three different small studies, with remarkably consistent findings, used kimchi intake as the intervention. In all three cases, waist circumference and BMI were decreased. Additionally, decreased insulin resistance and decreased blood pressure were found with the kimchi intervention [89–91] Similarly, a double-blind, placebo-controlled trial was conducted in a cohort of children with obesity. These children were given one daily probiotics for 16 weeks and were compared to placebo. At the conclusion of the study, the group who received daily probiotics had a significant decrease in body weight, percent body fat, reduction in level of interleukin-6, serum triglycerides, and an increase in Bifidobacterium compared with controls [92]. Overall, there appear to be a growing body of literature implicating a favorable gut microbiome phenotype for metabolic health. Additionally, we know that metabolic syndrome can negatively affect surgical outcomes. This possible connection invites future studies to determine the extent to which synbiotics may have positive effects on surgical outcomes by altering aspects of metabolic syndrome. Conclusion In this review, we have examined the inflammatory effects of surgery and the importance of the host-microbiome relationship on surgical outcomes. Multiple studies have demonstrated a beneficial effect of synbiotics in the perioperative period to decrease multiple negative outcomes. Dr. John Alverdy is a leader in rethinking surgical dogma and investigating the impact of resident human intestinal bacteria on surgical outcomes. His group’s work also suggests that even short-term gut microbiome pre-habilitation could alter surgical outcomes significantly. Future studies should consider evidence-based strain specific formulations and work to determine ideal duration of treatment. Additionally, dietary interventions, such as fermented foods and high fiber diets should be considered in perioperative regimens. Data Availability The data that support the findings of this study are available upon reasonable request. Compliance with Ethical Standards Conflict of Interest The authors declare no competing interests. Human and Animal Rights and Informed Consent This article does not contain any studies with human or animal subjects performed by any of the authors. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Papers of particular interest, published recently, have been highlighted as: • Of importance 1. Schrezenmeir J de Vrese M Probiotics, prebiotics, and synbiotics–approaching a definition Am J Clin Nutr 2001 73 2 Suppl 361S 364S 10.1093/ajcn/73.2.361s 11157342 2. Xiong RG Zhou DD Wu SX Huang SY Saimaiti A Yang ZJ Health benefits and side effects of short-chain fatty acids Foods Basel Switz 2022 11 18 2863 3. David LA Maurice CF Carmody RN Gootenberg DB Button JE Wolfe BE Diet rapidly and reproducibly alters the human gut microbiome Nature 2014 505 7484 559 563 10.1038/nature12820 24336217 4. West NP Pyne DB Cripps AW Christophersen CT Conlon MA Fricker PA Gut Balance, a synbiotic supplement, increases fecal Lactobacillus paracasei but has little effect on immunity in healthy physically active individuals Gut Microbes 2012 3 3 221 227 10.4161/gmic.19579 22572834 5. Choileain NN Redmond HP Cell response to surgery Arch Surg 2006 141 11 1132 1140 10.1001/archsurg.141.11.1132 17116807 6. Dąbrowska AM Słotwiński R The immune response to surgery and infection Cent Eur J Immunol 2014 39 4 532 537 10.5114/ceji.2014.47741 26155175 7. Shankar Hari M Summers C Major surgery and the immune system: from pathophysiology to treatment Curr Opin Crit Care 2018 24 6 588 593 10.1097/MCC.0000000000000561 30299310 8. Zhou C Wang Z Jiang B Di J Su X Monitoring pre- and post-operative immune alterations in patients with locoregional colorectal cancer who underwent laparoscopy by single-cell mass cytometry Front Immunol 2022 13 807539 10.3389/fimmu.2022.807539 35185893 9. Serhan CN Pro-resolving lipid mediators are leads for resolution physiology Nature 2014 510 7503 92 101 10.1038/nature13479 24899309 10. Lee EE Song KH Hwang W Ham SY Jeong H Kim JH Pattern of inflammatory immune response determines the clinical course and outcome of COVID-19: unbiased clustering analysis Sci Rep 2021 11 1 8080 10.1038/s41598-021-87668-z 33850271 11. Bano G Trevisan C Carraro S Solmi M Luchini C Stubbs B Inflammation and sarcopenia: a systematic review and meta-analysis Maturitas 2017 96 10 15 10.1016/j.maturitas.2016.11.006 28041587 12. Gentile LF Cuenca AG Efron PA Ang D Bihorac A McKinley BA Persistent inflammation and immunosuppression: a common syndrome and new horizon for surgical intensive care J Trauma Acute Care Surg 2012 72 6 1491 1501 10.1097/TA.0b013e318256e000 22695412 13. Feng X Valdearcos M Uchida Y Lutrin D Maze M Koliwad SK Microglia mediate postoperative hippocampal inflammation and cognitive decline in mice JCI Insight 2017 2 7 e91229 10.1172/jci.insight.91229 28405620 14. West NR McCuaig S Franchini F Powrie F Emerging cytokine networks in colorectal cancer Nat Rev Immunol 2015 15 10 615 629 10.1038/nri3896 26358393 15. Siddharthan R Chapek M Warren M Martindale R Probiotics in prevention of surgical site infections Surg Infect 2018 19 8 781 784 10.1089/sur.2018.231 16. Camilleri M Human intestinal barrier: effects of stressors, diet, prebiotics, and probiotics Clin Transl Gastroenterol 2021 12 1 e00308 10.14309/ctg.0000000000000308 33492118 17. Zaharuddin L Mokhtar NM Muhammad Nawawi KN Raja Ali RA A randomized double-blind placebo-controlled trial of probiotics in post-surgical colorectal cancer BMC Gastroenterol 2019 19 1 131 10.1186/s12876-019-1047-4 31340751 18. Lu R Shang M Zhang YG Jiao Y Xia Y Garrett S Lactic acid bacteria isolated from Korean kimchi activate the vitamin D receptor-autophagy signaling pathways Inflamm Bowel Dis 2020 26 8 1199 1211 10.1093/ibd/izaa049 32170938 19. Pojednic RM Ceglia L Lichtenstein AH Dawson-Hughes B Fielding RA Vitamin D receptor protein is associated with interleukin-6 in human skeletal muscle Endocrine 2015 49 2 512 520 10.1007/s12020-014-0505-6 25510525 20. Chen HL Hung KF Yen CC Laio CH Wang JL Lan YW Kefir peptides alleviate particulate matter <4 μm (PM4.0)-induced pulmonary inflammation by inhibiting the NF-κB pathway using luciferase transgenic mice Sci Rep 2019 9 1 11529 10.1038/s41598-019-47872-4 31395940 21. Thomas CM Versalovic J Probiotics-host communication: modulation of signaling pathways in the intestine Gut Microbes 2010 1 3 148 163 10.4161/gmic.1.3.11712 20672012 22. Canfora EE Blaak EE Acetate: a diet-derived key metabolite in energy metabolism: good or bad in context of obesity and glucose homeostasis? Curr Opin Clin Nutr Metab Care 2017 20 6 477 483 10.1097/MCO.0000000000000408 28795972 23. Tedelind S Westberg F Kjerrulf M Vidal A Anti-inflammatory properties of the short-chain fatty acids acetate and propionate: a study with relevance to inflammatory bowel disease World J Gastroenterol 2007 13 20 2826 2832 10.3748/wjg.v13.i20.2826 17569118 24. Föh B Buhre JS Lunding HB Moreno-Fernandez ME König P Sina C Microbial metabolite butyrate promotes induction of IL-10+IgM+ plasma cells PLoS ONE 2022 17 3 e0266071 10.1371/journal.pone.0266071 35333906 25. • Wastyk HC, Fragiadakis GK, Perelman D, Dahan D, Merrill BD, Yu FB, et al. Gut-microbiota-targeted diets modulate human immune status. Cell. 2021;184(16):4137–53.e14. This randomized controlled trial shows compelling evidence of the importance of diet on immune function. Beyond just supplements, fermented foods play an important role in modulating inflammation. 26. Lozupone CA Stombaugh JI Gordon JI Jansson JK Knight R Diversity, stability and resilience of the human gut microbiota Nature 2012 489 7415 220 230 10.1038/nature11550 22972295 27. Turnbaugh PJ Gordon JI The core gut microbiome, energy balance and obesity J Physiol 2009 587 Pt 17 4153 4158 10.1113/jphysiol.2009.174136 19491241 28. Blackwell GA Hunt M Malone KM Lima L Horesh G Alako BTF Exploring bacterial diversity via a curated and searchable snapshot of archived DNA sequences PLoS Biol 2021 19 11 e3001421 10.1371/journal.pbio.3001421 34752446 29. Merkow RP Ju MH Chung JW Hall BL Cohen ME Williams MV Underlying reasons associated with hospital readmission following surgery in the United States JAMA 2015 313 5 483 495 10.1001/jama.2014.18614 25647204 30. Keenan JE Speicher PJ Thacker JKM Walter M Kuchibhatla M Mantyh CR The preventive surgical site infection bundle in colorectal surgery: an effective approach to surgical site infection reduction and health care cost savings JAMA Surg 2014 149 10 1045 1052 10.1001/jamasurg.2014.346 25163027 31. Alverdy JC Hyman N Gilbert J Re-examining causes of surgical site infections following elective surgery in the era of asepsis Lancet Infect Dis 2020 20 3 e38 43 10.1016/S1473-3099(19)30756-X 32006469 32. Krezalek MA Hyoju S Zaborin A Okafor E Chandrasekar L Bindokas V Can Methicillin-resistant Staphylococcus aureus silently travel from the gut to the wound and cause postoperative infection? Modeling the “Trojan Horse Hypothesis” Ann Surg 2018 267 4 749 758 10.1097/SLA.0000000000002173 28187042 33. Anderson ADG McNaught CE Jain PK MacFie J Randomised clinical trial of synbiotic therapy in elective surgical patients Gut 2004 53 2 241 245 10.1136/gut.2003.024620 14724157 34. Horvat M Krebs B Potrc S Ivanecz A Kompan L Preoperative synbiotic bowel conditioning for elective colorectal surgery Wien Klin Wochenschr 2010 122 Suppl 2 26 30 10.1007/s00508-010-1347-8 20517667 35. McNaught CE Woodcock NP MacFie J Mitchell CJ A prospective randomised study of the probiotic Lactobacillus plantarum 299V on indices of gut barrier function in elective surgical patients Gut 2002 51 6 827 831 10.1136/gut.51.6.827 12427785 36. Rayes N Seehofer D Theruvath T Mogl M Langrehr JM Nüssler NC Effect of enteral nutrition and synbiotics on bacterial infection rates after pylorus-preserving pancreatoduodenectomy: a randomized, double-blind trial Ann Surg 2007 246 1 36 41 10.1097/01.sla.0000259442.78947.19 17592288 37. Reddy BS Macfie J Gatt M Larsen CN Jensen SS Leser TD Randomized clinical trial of effect of synbiotics, neomycin and mechanical bowel preparation on intestinal barrier function in patients undergoing colectomy Br J Surg 2007 94 5 546 554 10.1002/bjs.5705 17443852 38. Nomura T Tsuchiya Y Nashimoto A Yabusaki H Takii Y Nakagawa S Probiotics reduce infectious complications after pancreaticoduodenectomy Hepatogastroenterology 2007 54 75 661 663 17591036 39. Kanazawa H Nagino M Kamiya S Komatsu S Mayumi T Takagi K Synbiotics reduce postoperative infectious complications: a randomized controlled trial in biliary cancer patients undergoing hepatectomy Langenbecks Arch Surg 2005 390 2 104 113 10.1007/s00423-004-0536-1 15711820 40. Rayes N Seehofer D Theruvath T Schiller RA Langrehr JM Jonas S Supply of pre- and probiotics reduces bacterial infection rates after liver transplantation–a randomized, double-blind trial Am J Transplant Off J Am Soc Transplant Am Soc Transpl Surg 2005 5 1 125 130 10.1111/j.1600-6143.2004.00649.x 41. Rayes N Hansen S Seehofer D Müller AR Serke S Bengmark S Early enteral supply of fiber and Lactobacilli versus conventional nutrition: a controlled trial in patients with major abdominal surgery Nutr Burbank Los Angel Cty Calif 2002 18 7–8 609 615 10.1016/S0899-9007(02)00811-0 42. Eguchi S Takatsuki M Hidaka M Soyama A Ichikawa T Kanematsu T Perioperative synbiotic treatment to prevent infectious complications in patients after elective living donor liver transplantation: a prospective randomized study Am J Surg 2011 201 4 498 502 10.1016/j.amjsurg.2010.02.013 20619394 43. Tanaka K Yano M Motoori M Kishi K Miyashiro I Ohue M Impact of perioperative administration of synbiotics in patients with esophageal cancer undergoing esophagectomy: a prospective randomized controlled trial Surgery 2012 152 5 832 842 10.1016/j.surg.2012.02.021 22503510 44. Sugawara G Nagino M Nishio H Ebata T Takagi K Asahara T Perioperative synbiotic treatment to prevent postoperative infectious complications in biliary cancer surgery: a randomized controlled trial Ann Surg 2006 244 5 706 714 10.1097/01.sla.0000219039.20924.88 17060763 45. Zhang JW Du P Gao J Yang BR Fang WJ Ying CM Preoperative probiotics decrease postoperative infectious complications of colorectal cancer Am J Med Sci 2012 343 3 199 205 10.1097/MAJ.0b013e31823aace6 22197980 46. Chowdhury AH Adiamah A Kushairi A Varadhan KK Krznaric Z Kulkarni AD Perioperative probiotics or synbiotics in adults undergoing elective abdominal surgery: a systematic review and meta-analysis of randomized controlled trials Ann Surg 2020 271 6 1036 1047 10.1097/SLA.0000000000003581 31469748 47. Pitsouni E Alexiou V Saridakis V Peppas G Falagas ME Does the use of probiotics/synbiotics prevent postoperative infections in patients undergoing abdominal surgery? A meta-analysis of randomized controlled trials Eur J Clin Pharmacol 2009 65 6 561 570 10.1007/s00228-009-0642-7 19326107 48. Kinross JM Markar S Karthikesalingam A Chow A Penney N Silk D A meta-analysis of probiotic and synbiotic use in elective surgery: does nutrition modulation of the gut microbiome improve clinical outcome? JPEN J Parenter Enteral Nutr 2013 37 2 243 253 10.1177/0148607112452306 22750803 49. Skonieczna-Żydecka K Kaczmarczyk M Łoniewski I Lara LF Koulaouzidis A Misera A A systematic review, meta-analysis, and meta-regression evaluating the efficacy and mechanisms of action of probiotics and synbiotics in the prevention of surgical site infections and surgery-related complications J Clin Med 2018 7 12 E556 10.3390/jcm7120556 50. Nobuhara H Matsugu Y Soutome S Hayashida S Hasegawa T Akashi M Perioperative oral care can prevent surgical site infection after colorectal cancer surgery: a multicenter, retrospective study of 1,926 cases analyzed by propensity score matching Surgery 2022 172 2 530 536 10.1016/j.surg.2022.02.015 35396104 51. Cheema HA Shahid A Ayyan M Mustafa B Zahid A Fatima M Probiotics for the prevention of ventilator-associated pneumonia: an updated systematic review and meta-analysis of randomised controlled trials Nutrients 2022 14 8 1600 10.3390/nu14081600 35458162 52. Shimizu K Ogura H Kabata D Shintani A Tasaki O Ojima M Association of prophylactic synbiotics with reduction in diarrhea and pneumonia in mechanically ventilated critically ill patients: a propensity score analysis J Infect Chemother Off J Jpn Soc Chemother 2018 24 10 795 801 10.1016/j.jiac.2018.06.006 53. Watkinson PJ Barber VS Dark P Young JD The use of pre- pro- and synbiotics in adult intensive care unit patients: systematic review Clin Nutr Edinb Scotl 2007 26 2 182 192 10.1016/j.clnu.2006.07.010 54. Morrow LE Gogineni V Malesker MA Probiotic, prebiotic, and synbiotic use in critically ill patients Curr Opin Crit Care 2012 18 2 186 191 10.1097/MCC.0b013e3283514b17 22343306 55. Virk HS Wiersinga WJ Current place of probiotics for VAP Crit Care Lond Engl 2019 23 1 46 10.1186/s13054-019-2325-9 56. Fan QL Yu XM Liu QX Yang W Chang Q Zhang YP Synbiotics for prevention of ventilator-associated pneumonia: a probiotics strain-specific network meta-analysis J Int Med Res 2019 47 11 5349 5374 10.1177/0300060519876753 31578896 57. Sharif S Greer A Skorupski C Hao Q Johnstone J Dionne JC Probiotics in critical illness: a systematic review and meta-analysis of randomized controlled trials Crit Care Med 2022 50 8 1175 1186 10.1097/CCM.0000000000005580 35608319 58. Manzanares W Lemieux M Langlois PL Wischmeyer PE Probiotic and synbiotic therapy in critical illness: a systematic review and meta-analysis Crit Care Lond Engl 2016 19 19 262 10.1186/s13054-016-1434-y 59. Dehghani MH, Saghafi F, Bordbari Z, Zare-Kamali J, Jafari-Nedooshan J, Sahebnasagh A. Investigating the effect of oral synbiotic on enteral feeding tolerance in critically ill patients: a double-blinded controlled clinical trial of gut microbiota. Nutr Clin Pract Off Publ Am Soc Parenter Enter Nutr. 2022. 60. Lu SSM Mohammed Z Häggström C Myte R Lindquist E Gylfe Å Antibiotics use and subsequent risk of colorectal cancer: a Swedish nationwide population-based study J Natl Cancer Inst 2022 114 1 38 46 10.1093/jnci/djab125 34467395 61. Carr PR Weigl K Jansen L Walter V Erben V Chang-Claude J Healthy lifestyle factors associated with lower risk of colorectal cancer irrespective of genetic risk Gastroenterology 2018 155 6 1805 1815.e5 10.1053/j.gastro.2018.08.044 30201362 62. Watson KM, Gardner IH, Anand S, Siemens KN, Sharpton TJ, Kasschau KD, et al. Colonic microbial abundances predict adenoma formers. Ann Surg. 2021. 63. Manfredi S Bouvier AM Lepage C Hatem C Dancourt V Faivre J Incidence and patterns of recurrence after resection for cure of colonic cancer in a well defined population Br J Surg 2006 93 9 1115 1122 10.1002/bjs.5349 16804870 64. Schellenberg AE Moravan V Christian F A competing risk analysis of colorectal cancer recurrence after curative surgery BMC Gastroenterol 2022 22 1 95 10.1186/s12876-022-02161-9 35241002 65. Hermanek P Wiebelt H Staimmer D Riedl S Prognostic factors of rectum carcinoma–experience of the German Multicentre Study SGCRC German Study Group Colo-Rectal Carcinoma Tumori 1995 81 3 Suppl 60 64 66. Meyerhardt JA Niedzwiecki D Hollis D Saltz LB Hu FB Mayer RJ Association of dietary patterns with cancer recurrence and survival in patients with stage III colon cancer JAMA 2007 298 7 754 764 10.1001/jama.298.7.754 17699009 67. • Gaines S, van Praagh JB, Williamson AJ, Jacobson RA, Hyoju S, Zaborin A, et al. Western diet promotes intestinal colonization by collagenolytic microbes and promotes tumor formation after colorectal surgery. Gastroenterology. 2020;158(4):958–70.e2. Alverdy’s group again challenges traditional dogma about the impact of intestinal bacteria on the colon. These data indicate not only that diet can change the microbiome, but demonstrate a mechanism by which “undesirable” bacteria damage the gut. 68. Kang CY Halabi WJ Chaudhry OO Nguyen V Pigazzi A Carmichael JC Risk factors for anastomotic leakage after anterior resection for rectal cancer JAMA Surg 2013 148 1 65 71 10.1001/2013.jamasurg.2 22986932 69. Slieker JC Daams F Mulder IM Jeekel J Lange JF Systematic review of the technique of colorectal anastomosis JAMA Surg 2013 148 2 190 201 10.1001/2013.jamasurg.33 23426599 70. Mirnezami A Mirnezami R Chandrakumaran K Sasapu K Sagar P Finan P Increased local recurrence and reduced survival from colorectal cancer following anastomotic leak: systematic review and meta-analysis Ann Surg 2011 253 5 890 899 10.1097/SLA.0b013e3182128929 21394013 71. Bosmans JWAM Jongen ACHM Birchenough GMH Nyström EEL Gijbels MJJ Derikx JPM Functional mucous layer and healing of proximal colonic anastomoses in an experimental model Br J Surg 2017 104 5 619 630 10.1002/bjs.10456 28195642 72. Williamson AJ Alverdy JC Influence of the microbiome on anastomotic leak Clin Colon Rectal Surg 2021 34 6 439 446 10.1055/s-0041-1735276 34853567 73. Thompson SK Chang EY Jobe BA Clinical review: healing in gastrointestinal anastomoses, part I Microsurgery 2006 26 3 131 136 10.1002/micr.20197 16518804 74. Munireddy S Kavalukas SL Barbul A Intra-abdominal healing: gastrointestinal tract and adhesions Surg Clin North Am 2010 90 6 1227 1236 10.1016/j.suc.2010.08.002 21074038 75. Anderson DI Keskey R Ackerman MT Zaborina O Hyman N Alverdy JC Enterococcus faecalis is associated with anastomotic leak in patients undergoing colorectal surgery Surg Infect 2021 22 10 1047 1051 10.1089/sur.2021.147 76. Belmouhand M Krohn PS Svendsen LB Henriksen A Hansen CP Achiam MP The occurrence of Enterococcus faecium and faecalis is significantly associated with anastomotic leakage after pancreaticoduodenectomy Scand J Surg SJS Off Organ Finn Surg Soc Scand Surg Soc 2018 107 2 107 113 77. Shogan BD Belogortseva N Luong PM Zaborin A Lax S Bethel C Collagen degradation and MMP9 activation by Enterococcus faecalis contribute to intestinal anastomotic leak Sci Transl Med 2015 7 286 286ra68 10.1126/scitranslmed.3010658 25947163 78. Komen N Morsink MC Beiboer S Miggelbrink A Willemsen P van der Harst E Detection of colon flora in peritoneal drain fluid after colorectal surgery: can RT-PCR play a role in diagnosing anastomotic leakage? J Microbiol Methods 2009 79 1 67 70 10.1016/j.mimet.2009.08.004 19683548 79. Hyoju SK Adriaansens C Wienholts K Sharma A Keskey R Arnold W Low-fat/high-fibre diet prehabilitation improves anastomotic healing via the microbiome: an experimental model Br J Surg 2020 107 6 743 755 10.1002/bjs.11388 31879948 80. Kok DE Arron MNN Huibregtse T Kruyt FM Bac DJ van Halteren HK Association of habitual preoperative dietary fiber intake with complications after colorectal cancer surgery JAMA Surg 2021 156 9 827 835 10.1001/jamasurg.2021.2311 81. Kotzampassi K Stavrou G Damoraki G Georgitsi M Basdanis G Tsaousi G A four-probiotics regimen reduces postoperative complications after colorectal surgery: a randomized, double-blind, placebo-controlled study World J Surg 2015 39 11 2776 2783 10.1007/s00268-015-3071-z 25894405 82. Veziant J Bonnet M Occean BV Dziri C Pereira B Slim K Probiotics/synbiotics to reduce infectious complications after colorectal surgery: a systematic review and meta-analysis of randomised controlled trials Nutrients 2022 14 15 3066 10.3390/nu14153066 35893922 83. Norris P Ralph N Moloney C Does metabolic syndrome predict surgical complications? A protocol for a systematic review and meta-analysis Syst Rev 2017 6 1 115 10.1186/s13643-017-0515-6 28623943 84. Tzimas P Petrou A Laou E Milionis H Mikhailidis DP Papadopoulos G Impact of metabolic syndrome in surgical patients: should we bother? Br J Anaesth 2015 115 2 194 202 10.1093/bja/aev199 26109210 85. • Keskey R, Papazian E, Lam A, Toni T, Hyoju S, Thewissen R, et al. Defining microbiome readiness for surgery: dietary prehabilitation and stool biomarkers as predictive tools to improve outcome. Ann Surg. 2022;276(5):e361–9. Not only does what we eat affect the bacteria in our gut, but this change can happen quickly. These data indicate that we may be able to alter surgical outcomes with just a short prehabilitation period targeting the gut microbiome. 86. Tims S Derom C Jonkers DM Vlietinck R Saris WH Kleerebezem M Microbiota conservation and BMI signatures in adult monozygotic twins ISME J 2013 7 4 707 717 10.1038/ismej.2012.146 23190729 87. Bauer PV Hamr SC Duca FA Regulation of energy balance by a gut-brain axis and involvement of the gut microbiota Cell Mol Life Sci CMLS 2016 73 4 737 755 10.1007/s00018-015-2083-z 26542800 88. Vrieze A Van Nood E Holleman F Salojärvi J Kootte RS Bartelsman JFWM Transfer of intestinal microbiota from lean donors increases insulin sensitivity in individuals with metabolic syndrome Gastroenterology 2012 143 4 913 916.e7 10.1053/j.gastro.2012.06.031 22728514 89. Han K Bose S Wang JH Kim BS Kim MJ Kim EJ Contrasting effects of fresh and fermented kimchi consumption on gut microbiota composition and gene expression related to metabolic syndrome in obese Korean women Mol Nutr Food Res 2015 59 5 1004 1008 10.1002/mnfr.201400780 25688926 90. Kim EK An SY Lee MS Kim TH Lee HK Hwang WS Fermented kimchi reduces body weight and improves metabolic parameters in overweight and obese patients Nutr Res N Y N 2011 31 6 436 443 10.1016/j.nutres.2011.05.011 91. An SY Lee MS Jeon JY Ha ES Kim TH Yoon JY Beneficial effects of fresh and fermented kimchi in prediabetic individuals Ann Nutr Metab 2013 63 1–2 111 119 10.1159/000353583 23969321 92. Nicolucci AC Hume MP Martínez I Mayengbam S Walter J Reimer RA Prebiotics reduce body fat and alter intestinal microbiota in children who are overweight or with obesity Gastroenterology 2017 153 3 711 722 10.1053/j.gastro.2017.05.055 28596023
PMC010xxxxxx/PMC10061391.txt	==== Front Cancer Immunol Immunother Cancer Immunol Immunother Cancer Immunology, Immunotherapy 0340-7004 1432-0851 Springer Berlin Heidelberg Berlin/Heidelberg 36995489 3411 10.1007/s00262-023-03411-9 Meeting Report Cancer immunity and immunotherapy beyond COVID-19 Bellone Matteo [email protected] 1 Brevi Arianna 1 Bronte Vincenzo 2 Dusi Silvia 2 Ferrucci Pier Francesco 3 Nisticò Paola 4 Rosato Antonio 56 Russo Vincenzo 7 Sica Antonio 89 Toietta Gabriele 4 Colombo Mario Paolo [email protected] 10 1 grid.18887.3e 0000000417581884 Unit of Cellular Immunology, I.R.C.C.S. Ospedale San Raffaele, Milan, Italy 2 grid.411475.2 0000 0004 1756 948X Immunology Section, Department of Medicine, University and Hospital Trust of Verona, Verona, Italy 3 grid.15667.33 0000 0004 1757 0843 Unit of Tumor Biotherapy, Department of Experimental Oncology, I.R.C.C.S. European Institute of Oncology, Milan, Italy 4 grid.417520.5 0000 0004 1760 5276 Unit Tumor Immunology and Immunotherapy, I.R.C.C.S. Regina Elena National Cancer Institute, Rome, Italy 5 grid.5608.b 0000 0004 1757 3470 Department of Surgery, Oncology and Gastroenterology, University of Padova, Padua, Italy 6 grid.419546.b 0000 0004 1808 1697 Veneto Institute of Oncology IOV-I.R.C.C.S, Padua, Italy 7 grid.18887.3e 0000000417581884 Unit of Immuno-Biotherapy of Melanoma and Solid Tumors, I.R.C.C.S. Ospedale San Raffaele, Milan, Italy 8 grid.417728.f 0000 0004 1756 8807 Molecular Immunology Lab, I.R.C.C.S. Humanitas Clinical and Research Center, Rozzano (Mi), Italy 9 grid.16563.37 0000000121663741 Department of Pharmaceutical Sciences, University of Piemonte Orientale “A. Avogadro”, Novara, Italy 10 grid.417893.0 0000 0001 0807 2568 Molecular Immunology Unit, Department of Research, Fondazione I.R.C.C.S. Istituto Nazionale Dei Tumori, Via Amadeo 42, 20068 Milan, Italy 30 3 2023 2023 72 7 25412548 6 9 2022 12 2 2023 © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Keywords Immunotherapy Cancer vaccines Checkpoint blockade agents Adoptive immunotherapy Targeted therapies NIBIT issue-copyright-statement© Springer-Verlag GmbH Germany, part of Springer Nature 2023 ==== Body pmcIntroduction The COVID-19 pandemic has forced all of us to change priorities and perspectives. The reaction of the scientific community has been focused, fast and incredibly effective. It is difficult to recall in the history of mankind such a cohesion of intents and efforts among countries in defeating a new threat to humanity. We have learned that joining forces is the winning strategy against any threat, cancer included. However, SARS-CoV-2 only partially distracted the basic, translational, and clinical research in cancer. Inspired by this overwhelming experience and eager to share the last groundbreaking discoveries in cancer immunology and immunotherapy with the scientific community and for the benefit of cancer patients, the Italian Network for the Biotherapy of Cancer (NIBT) organized the XIX NIBIT Meeting 2021, whose main theme was “Cancer immunity and immunotherapy beyond the COVID-19 pandemic.” The meeting rolled out in the web on October 14–15, 2021, and gathered top clinicians and scientists to discuss about novel concepts in cancer immunology, such as trained immunity and cancer & immune metabolism. Almost 200 delegates were updated on cutting-hedge therapies in hematologic malignancies and solid tumors including melanoma, lung, breast, prostate, head and neck and several others. Each session hosted a 20’ open discussion animated by experts in the field. There was plenty of space for oral communications from the youngest investigators. Three poster sessions in the morning allowed 20 investigators to orally present their most recent and exciting findings (Supplementary Fig. S1). Thus, NIBIT was proud to meet the educational needs of its members and of young investigators committed to cancer immunotherapy. Session 1. What’s new in cancer immunotherapy The XIX NIBIT meeting began with a session focused on novelties in clinical cancer immunotherapy. This session was jointly organized by the NIBIT and the Associazione Italiana di Oncologia Medica (AIOM), and witnessed Rita Chiari (Padova, Italy), Lucia Del Mastro (Genova, Italy), Wolf-Herman Fridman (Paris, France) and Paolo Ascierto (Napoli, Italy) as discussants. Since the FDA approval of Ipilimumab in 2011, several immune checkpoint inhibitors (ICIs) have been added to the therapeutic arsenal against cancer [1]. These agents, in several cases, allow durable responses with acceptable safety and are now approved for the treatment of various types of malignancy. However, a relevant percentage of cancer patients still do not benefit from ICI treatment [1]. Therefore, preclinical and clinical research are focused on how to improve the outcome of non-responders. Within this vein, Alexander Eggermont (Utrecht, The Netherlands) discussed about recent advancements in the use ICI for melanoma patients. Whereas adjuvant therapy is currently applied to patients with stage III or IIB/C melanoma, most melanoma patients are diagnosed at stage I/IIA. Despite an excellent prognosis, and a 10-year survival rate higher than 90%, stage I/IIA melanomas account for more than a half of future melanoma-related deaths [2, 3]. Therefore, an unmet clinical need is to identify patients who will more likely relapse after surgery. The CP-GEP model combines patient age, Breslow thickness and gene expression profile of melanoma biopsy. The resulting score may improve the detection of melanoma patients that could avoid sentinel lymph node biopsy because of their low risk of nodal metastasis. The same model can be used to identify stage I/IIA patients who are at high risk of disease relapse and support clinical decision-making on adjuvant therapy [4]. Similarly, in the ongoing NivoMela trial (NCT04309409) stage II melanoma patients are screened by the MelaGenix GEP score to identify subjects at high risk of relapse, and patients are eventually randomized to receive either nivolumab as adjuvant treatment or observation only. In the neoadjuvant setting, data from the OpACIN-neo trial (NCT02977052), after a median follow-up of 24.6 months, showed a high rate of pathologic response and only the 2% within this group of patients relapsed. The PRADO trial (NCT02977052), an extension cohort of the OpACIN-neo study, aims at assessing personalized response-driven adjuvant therapy. In this trial, lymph node dissection was omitted in 59 (60%) patients, the consequences were fewer surgery-related adverse events and higher quality of life scores. The ongoing NADINA trial (NCT04949113) will further clarify the role of lymph node dissection in the neoadjuvant era. Adoptive T cell therapy (ACT) is one of the most promising innovative approaches among cancer treatments. Chiara Bonini (Milan, Italy) explored the major challenges of this area of research. CD44v6 emerged as a new target, expressed in acute myeloid leukemia (AML) and multiple myeloma (MM) and associates with poor prognosis [5]. A clinical trial to assess safety, antitumor activity, and feasibility of CD44v6 CAR T cell immunotherapy in AML and MM is currently ongoing (NCT04097301). One way to improve ACT efficacy, that showed promising results, consists in enabling T cells to fight the immunosuppressive tumor microenvironment [6] by editing endogenous TCR genes and inhibitory receptor genes [7]. Federico Cappuzzo (Rome, Italy) presented an impressive overview on progresses in non-small cell lung cancer (NSCLC) treatment. In the adjuvant setting, the data of Impower010, which evaluated Atezolizumab after surgery, have demonstrated a significant impact over disease free survival (DFS) [8]. In the locally advanced setting, the COAST trial (NCT03822351) investigated the addition of Oleclumab or Monalizumab to Durvalumab with interesting results. In the metastatic disease, data from EMPOWER-Lung 3 may add Cemiplimab among the therapeutic arsenal for PD-L1 negative NSCLC patients [9]. Moreover, in first line for advanced NSCLC patients, the combination of Durvalumab, Trametinib and chemotherapy showed promising results in the POSEIDON trial (NCT03164616) [10]. Immunotherapy has already changed the therapeutic algorithm of triple negative breast cancer patients. Rita Nanda (Chicago, USA) showed the results of the Impassion130 trial that led to the accelerated FDA approval in 2019 of Nab-paclitaxel plus Atezolizumab in PD-L1 positive triple negative breast cancer (TNBC) metastatic patients [11]. The Keynote-355 trial evaluated Pembrolizumab in association with chemotherapy and demonstrated a treatment benefit limited to PD-L1+ tumors (CPS > 10 using DAKO 22C3), which granted FDA accelerated approval on November 13th, 2020 [12]. In Stage II-III TNBC, as neoadjuvant treatment associated to chemotherapy, both Pembrolizumab (Keynote522) and Atezolizumab (IMpassion 131) were associated with improvement in pathologic complete response (NCT0303648; NCT03125902). Finally, Rita Nanda presented encouraging data form the I-SPY 2, a phase II platform trial, that used clinical biomarkers to classify breast cancer into 10 subtypes and assign the treatment arm, with the goals to tailor the treatment fitting the patient best (NCT01042379). Session 2. Adaptive and trained immunity in health and cancer The Società Italiana di Immunologia, Immunologia Clinica ed Allergologia (SIICA) contributed to the organization of Session 2. The concept of epigenetic imprinting and editing of the immune response was discussed in this session by exploring its relevance in cancer progression and in the implementation of immunotherapeutic approaches. Angela Santoni (Rome, Italy), Catherine Sautes-Fridman (Paris, France), Marco Cassatella (Verona, Italy) and Renato Ostuni (Milano, Italy) acted as discussants in this session. Mihai Netea (Bonn, Germany) discussed the metabolic status in trained monocytes, by showing that the metabolite mevalonate, of the cholesterol biosynthetic pathway, mediated training via activation of insulin growth factor 1 receptor and mTOR and subsequent histone modifications, in inflammatory pathways [13]. Statins, which block mevalonate generation, by interfering with the biosynthetic enzyme HMG-CoA, prevent trained immunity induction. Monocytes of patients with hyper immunoglobulin D syndrome, who are mevalonate kinase deficient and accumulate mevalonate, display constitutive trained immunity, along with typical attacks of sterile inflammation. He also showed that functional reprogramming of hematopoietic stem and progenitor cells (HSPCs) and peripheral monocytes characterize the induction of trained immunity and the beneficial effects of Bacille-Calmette-Guérin (BCG) vaccination, with a major difference in HPSC transcriptome and a bias toward myelopoiesis [14]. A double-blind randomized trial, showed that BCG vaccination is safe and can protect the elderly against new infections. On this line, Mihai showed how intravenous administration of BCG protects mice against lethal SARS-CoV-2 challenge and how trained immunity may represent a tool against a pandemic [15]. Triantafyllos Chavakis (Dresden. Germany) discussed the relevance of trained granulopoiesis in cancer. He showed that certain infections (e.g., Candida albicans—ß-glucan), vaccines (e.g., BCG) or Western diet can promote an enhanced response of myeloid cells to a secondary challenge, and ß-glucan-induced long-term myelopoiesis/granulopoiesis bias is transmissible to recipient mice [16]. He questioned as to whether trained immunity is involved in the anti-tumor response of beta-glucan. Indeed, ß-glucan enhances antitumor immune responses by regulating differentiation and function of monocytic myeloid-derived suppressor cells. ß-glucan treatment subverted the suppression of myeloid-derived suppressor cells by inducing PMN-MDSC apoptosis and M-MDSC differentiation to antigen presenting cell (APC) in cancer. In the B16-F10 melanoma model, innate immune training via ß-glucan inhibited tumor growth [17]. The anti-tumor effect of ß-glucan-induced trained immunity was associated with transcriptomic and epigenetic rewiring of granulopoiesis and neutrophil reprogramming toward an anti-tumor phenotype, a process that required type-I interferon (IFN) signaling. Noteworthy, trained neutrophils suppressed tumor growth in a ROS-dependent manner, whereas inhibition of type-I IFN signaling abrogated the innate immune training of neutrophils toward an anti-tumor phenotype. He concluded that appropriate rewiring of granulopoiesis is a novel therapeutically relevant anti-tumor facet of trained immunity. Miriam Merad (New York, USA). After reviewing the successes of immunotherapy, Miriam Merad discussed the interactions between APCs and T cells as central events for an effective antitumor response. Her group performed single-cell mapping analysis of NSCLC, hepatocellular carcinoma (HCC), colorectal cancer (CRC) lesions during treatment with checkpoint blockade, using a CITE-Seq approach. The analysis revealed common myeloid patterns across patients and across tumor types. They identified a lung cancer activation module (LCAMhi), consisting of PDCD1+ CXCL13 + activated T cells, IgG+ plasma cells, and SPP1+ macrophages, which was enriched in multiple NSCLC cohorts [18]. Further, using single-cell RNA sequencing in human and mouse non-small-cell lung cancers, they identified a cluster of DCs named ‘mature DCs enriched in immunoregulatory molecules (mregDCs), co-expressing immunoregulatory genes (Cd274, Pdcd1lg2 and Cd200) and maturation genes (Cd40, Ccr7and Il12b) [19]. These mregDCs have been found in normal tissues and in other inflammatory conditions (i.e., mouse normal lung and lymph nodes, human lung donors, human lung fibrosis). Upon tumor antigen uptake, DC1 and DC2 may undergo a molecular transformation (mregDC) expressing both regulatory and immunogenic programs and a migratory program to guide them to tertiary lymphoid structures (TLS) or lymph nodes (LN). These events are paralleled by PD-L1 expression, through engagement of the receptor tyrosine kinase AXL, while upregulation of interleukin (IL)-12 depends strictly on IFNγ and is controlled negatively by IL-4 signaling. Claudio Tripodo (Palermo, Italy) discussed how recombination and revision of the TCR machinery in the tumor microenvironment hints at the rising immune pressure, suggesting that the interface between T cells and tumor cells has prognostic significance. This assumption was based on the observation that the clonal status of TILs and TME is variably associated with prognosis in the presence or absence of immune checkpoint blockade [20]. He hypothesized that within the TME, TILs could re-express key elements of the TCR recombination machinery via gene recombination depending on RAG1/2. Signs of RAG1/2 expression events were indeed detected in the TME and increased expression of rag1/2 and dntt was observed along with T cell infiltration, in a model of DNA mismatch repair protein Mlh1-deficient 4T1 tumor [21]. In agreement, analysis of harmonized single-cell RNA sequencing data sets of human cancers identified a very small fraction of tumor-associated T cells, characterized by the expression of recombination/revision machinery transcripts. At the end of Session 2, Pier Francesco Ferrucci (Milan, Italy) introduced the Giorgio Parmiani Keynote Lecture 2021. He briefly honored the memory of Giorgio Parmiani, enthusiastic founder of the NIBIT and its first president, who passed away on March 21, 2021. Born in 1938, Giorgio Parmiani was a charismatic and internationally recognized pioneer in multiple fields of cancer immunobiology. In 2008, he was awarded the Smalley Price from the Society for Immunotherapy of Cancer (SITC), and in 2020, he and his teams received the SITC Team Science Award, being the face of NIBIT in the World Immunotherapy Council since 2010. The Giorgio Parmiani Keynote Lecture 2021 was honored to Bernard A. Fox (Providence, USA), who, among the many career achievements, also served as SITC president. Berny Fox delivered a lecture on: Translation, An Iterative and Team Process – Our Path to the Development of Triplet Cancer Immunotherapy. Starting from the evidence that we still do not know why not all metastatic cancer patients benefit from immunotherapy, he proposed to abandon the T cell-centric view, and focus instead on the contribution of NK cells, B cells and innate effectors. B cells can show effector mechanisms through complement activation, antibody production, direct cytotoxicity, induced phagocytosis and apoptosis. On the other hand, they could also act as suppressors of the immune responses. Cancer patients have broad anticancer immunity against non-mutated epitopes and shared antigens, showing a diversity of antigen-specific responses. In this sense, IgG antibodies could identify targets of CD8 T cell response, and once stimulated with shared antigens and cytokines, can “re-activate” T cells to kill cancer cells. Coordinated responses to individual tumor antigens by IgG antibody and CD8+ T cells, both recognizing component of the same long peptide and the tumor, have been demonstrated following cancer vaccination. On the other hand, it is good news that the immune system recognizes not-mutated shared antigens in different cancers, said Fox, so the challenge is to identify a vaccine with large number of overexpressed cancer antigens to prime or “re-activate” T cells. Hence, we can start the engine, accelerate, and relieve the brake simultaneously by combining vaccination with stimulating antibodies and immune check point blockade. Triple combination immunotherapy clinical trials are ongoing using complex vaccines, plus co-stimulation with anti-OX40 or anti-GITR, plus anti-PD1. Session 3. Metabolism at the intersection between cancer and immunity The Società Italiana di Cancerologia (SIC) helped the NIBIT to organize Session 3, which was centered on the metabolic switch in TME. Paola Chiarugi (Firenze, Italy), Antonio Rosato (Padova, Italy), Vincenzo Russo (Milan, Italy) and Ivan Zanoni (Boston, USA) were invited to chair and discuss this issue. In recent years, metabolism has been reported to influence both tumor and immune cells. Several reports have recently shown that the pharmacologic and genetic manipulation of metabolic pathways restores antitumor immune responses by activating or suppressing distinct cellular elements in the TME. Marina Garassino (Chicago, USA) discussed how obesity may interfere with spontaneous or induced immune responses [22]. Antonio Sica (Novara, Italy) discussed the pro-tumor role of myeloid cells and how to target them to unleash antitumor immune responses. Particularly, he discussed the steps of the emergency myelopoiesis, which determines the appearance of RORC1/RORγ+ myeloid cells infiltrating advanced tumors [23]. He also described strategies to target pro-tumor myeloid cells by antibodies recognizing colony stimulating factors or their receptors, such as anti-colony stimulating factor 1 receptor, or by drugs antagonizing the CXCR4 chemokine receptor, which is involved in the mobilization of myeloid precursors. He introduced the role of the nicotinamide phosphoribosyltransferase (NAMPT) enzyme in myeloid cell mobilization. NAMPT is the rate-limiting enzyme in the nicotinamide adenine dinucleotide pathway that converts nicotinamide to nicotinamide mononucleotide, thus controlling pro-tumor myeloid cell mobilization [24]. Finally, he focused on a newly identified pro-tumor subset of F4/80hiCD115hiC3aRhi TAMs expressing the heme-oxygenase 1 enzyme and involved in iron metabolism. This subset favors immunosuppression, angiogenesis and epithelial-to-mesenchymal transition. F4/80hiCD115hiC3aRhi TAMs originate from specific F4/80+HO-1+ bone marrow precursors and accumulate in the blood of patients affected by cancer. Of note, genetic or pharmacologic targeting of this subset blocked metastasis formation and improved anticancer immunotherapy. The relative expression of HO-1 in peripheral monocyte subsets, as well as in tumor lesions, impacted on the survival of advanced melanoma patients [25]. Roberta Zappasodi (New York, USA) described the role of glucose metabolism in Treg activity and how uncoupling glycolytic metabolism in Treg improves cancer immunotherapy. She showed that knock down of the gene encoding lactate dehydrogenase A in glycolytic tumors (glycolysis-defective tumors) improves tumor responses to CTLA-4 blockade. Investigating TIL subsets sensitive to this mechanism, she observed that CTLA-4 blockade-induced Treg instability in glycolysis-defective tumors, which was dependent on local lactate:glucose ratio. Finally, she observed that CTLA-4 blockade triggered CD28 signaling in Tregs ultimately promoting Treg glycolysis. Glycolysis supported Treg proliferation at the cost of reduced functional stability, namely increased IFN-γ production associated with reduced Treg suppression [26]. Dmitry Gabrilovich (Gaithersburg, USA) discussed the role of lipids and lipid metabolism in the regulation of MDSCs. He showed that PMN-MDSCs blocked cross-presentation by DCs. This effect was associated with the transfer of oxidized lipids to DCs. Moreover, he showed that PMN-MDSC generate oxidized lipids through the activity of myeloperoxidase (MPO). Indeed, MPO-deficient PMN-MDSCs did not dampen DCs. Of note, the pharmacological inhibition of MPO potentiated the antitumor effects of immune checkpoint blockade in different tumor models [27]. In addition, he discussed the role of endoplasmic reticulum (ER) stress response in the suppressive activity of tumor-infiltrating MDSCs. He showed that the acquisition of immune-suppressive activity by PMN-MDSCs in cancer was also controlled by IRE1α and ATF6 pathways of the ER stress response. Blockade of the ER stress response restored antitumor immune responses through the abrogation of PMN-MDSC activity [28]. Finally, he investigated the reactivation of dormant tumor cells, which is responsible for cancer patients’ mortality. He showed that stress hormones induced a rapid release of proinflammatory S100A8/A9 proteins by neutrophils. S100A8/A9 induced the activation of MPO, leading to the accumulation of oxidized lipids in these cells. Once released, these lipids upregulated the fibroblast growth factor pathway in tumor cells, favoring the formation of new tumor lesions. Finally, targeting of S100A8/A9 proteins abrogated stress-induced reactivation of dormant tumor cells [29]. Finally, Teresa Manzo (Milan, Italy), selected abstract, reported the identification of lipids endowed with the potential to differentiate antigen-specific T cells toward T cell memory cells. This metabolic rewiring of human and mouse T cells can be exploited to generate more potent tumor-specific CD8+ T cells for adoptive cell therapy purposes [30]. Session 4. Targeting immune-related tumor cell-extrinsic mechanisms Section 4 focused on tumor cell-extrinsic mechanisms that modulate cancer immunity also impacting cancer immunotherapy. The session was jointly organized with the Alleanza Contro il Cancro (ACC) and witnessed Paola Nisticò (Rome), Matteo Bellone (Milan), Vincenzo Bronte (Verona) and Rugero De Maria (Rome) as discussants. The tumor microenvironment organizes a metabolic barrier, hampering antitumor functions and promoting in turn resistance to immunotherapy [31]. Massimiliano Mazzone (Leuven, Belgium) presented interesting data emerging from computational analysis of the genes upregulated in human and murine transcriptomic and metabolomic datasets from non-responder vs responder to ICIs. Mazzone and collaborators identified an enzyme among the upregulated genes correlating to ICI resistance. The expression of this pyrimidine salvage pathway enzyme was acquired by pancreatic ductal adenocarcinoma (PDAC) tumor epithelial cells and correlated with poor disease outcome. In PDAC mouse models, enzyme knock down in cancer cells promoted tumor regression when combined with ICI, which correlated with increased number of activated CD8+ T cells and reduced numbers of immunosuppressive TAMs in tumors. The mechanism is still under investigation. Thus, metabolic cues might be exploited for therapeutic purposes to overcome resistance to cancer immunotherapy [32]. To date, PDAC remains a highly aggressive and treatment-refractory disease, characterized by stroma-rich and desmoplastic areas characterized by the presence of carcinoma-associated fibroblasts (CAFs) and stellate cells. In this regard, modification of the tumor stroma, with a particular focus on CAFs, is an attractive strategy to improve PDAC patients’ outcome. Shannon Turley (San Francisco, USA) reported on a recent work from her group aimed at defining the nature of the stromal compartment and its heterogeneity during PDAC evolution [33]. They performed bulk and single-cell RNAseq of stromal cells in normal tissues, nonmalignant adjacent tissue, and early and advanced tumors from Pdx1cre/ + ;LSL-KrasG12D/ + ;p16/p19flox/flox (KPP) mice. The analysis revealed fibroblast heterogeneity in healthy pancreas, which dictate the development trajectory of CAFs in the KPP mouse model. Among the different CAF clusters, two major subtypes arose after mapping the transcriptional changes during PDAC evolution. One was of particular interest due to its high representation in late stages of tumorigenesis and its TGFβ activation signature, which correlated with poor prognosis in PDAC patients. The transmembrane protein LRRC15 (Leucine-Rich Repeat Containing 15) was sufficient to distinguish TGFβ-driven CAFs from other fibroblast subsets in PDAC specimens. LRRC15 protein can be upregulated by TGFβ and is absent/low in normal tissues but strongly expressed in the stromal compartment of several tumor types [i.e., pancreatic, breast, and head and neck cancers; ref. [34]]. The presence of LRRC15+ CAFs was validated in published data of patients with PDAC [35], where the TGFβ-driven cluster represent about 52% of CAFs. Additionally, high expression of LRRC15 CAF signature and worse outcome were found in urothelial bladder cancer patients treated with anti-PD-L1 (atezolizumab), specifically in immune-excluded tumors. Importantly, also PDACs exhibited similar immune-desert landscapes. Additional data about the function of LRRC15+ CAFs and their reprogramming are needed to optimize fibroblast modulation and immunotherapy. The talk of Kathy McCoy (Calgary, Canada) was the trait d'union between metabolism and microbiota. She elegantly described how our microbes may influence the treatment of cancer through metabolites. She started from the observation that anti-PD-L1 and anti-CTLA4 allowed better tumor control and accumulation of tumor-infiltrating lymphocytes (TILs) in a CRC model driven by dextran sulfate sodium and azoxymethane [36]. This benefic effect could be transferred by transplanting microbial species (e.g., Bifidobacterium pseudolongum) or serum from responders. In the serum, inosine produced by Bifidobacterium pseudolongum and Akkermansia mediated tumor control by activating the cognate adenosine A2A receptor on T cells in the presence of costimulatory signals. However, better tumor control was obtained by combining these approaches with anti-CTLA4, which decreased gut barrier function and favored systemic translocation of inosine and activation of antitumor T cells [36]. The selected abstract of this session was from Laura Lucia Cogrossi (Milan, Italy). She reported on a recent publication showing that distinct Prevotella species differently impact induction of Th17 cells and in vivo tumor growth [37]. She investigated the mechanisms by which Prevotella heparinolytica (Ph) and Prevotella melaninogenica (Pm) interact with dendritic cells, inducing the release pro-inflammatory cytokines. Ph favored the release of cytokines promoting the switch to Th17 cells. Preliminary data suggested that the interaction between DCs and the two Prevotella strains occurs through different toll-like receptors. Together the last two presentations taught us that mere taxonomy of commensal bacteria is not enough to understand the relevant interactions with the immune system of the host. Conclusions The XIX NIBIT meeting smoothly rolled out in a stimulating atmosphere, regardless of the hurdles imposed by COVID-19 pandemic. Delegates were updated on the most recent discoveries in cancer immunology and immunotherapy. Additionally, several findings collected in inflammatory diseases including COVID-19 and reported at the meeting, provided relevant clues to better understand cancer-immune cell interactions. Supplementary Table 1 summarizes topics and take home message of every presentations. Sessions were rich in discussions and the youngest investigators had the opportunity to confront established researchers. The XIX annual meeting of the NIBIT was adjourned with the promise to meet in person in Padova in 2022. Supplementary Information Below is the link to the electronic supplementary material.Supplementary file 1 (PDF 107 kb) Supplementary file 2 (DOCX 21 kb) Abbreviations ACC Alleanza contro il cancro ACT Adoptive cell therapy AIOM Associazione Italiana di oncologia medica AML Acute myeloid leukemia APC Antigen presenting cell BCG Bacille-Calmette-Guérin CAF Carcinoma-associated fibroblast CDA Cytidine deaminase CRC Colorectal cancer DC Dendritic cell DFS Disease free survival HCC Hepatocellular carcinoma HSPC Hematopoietic stem and progenitor cell ICI Immune checkpoint inhibitor IFN Interferon IL Interleukin LN Lymph node LRRC15 Leucine-rich repeat containing 15 MDSC Myeloid-derived suppressor cell M-MDSC Monocyte myeloid-derived suppressor cell MM Multiple myeloma MPO Myeloperoxidase mregDC Dendritic cell enriched in immunoregulatory molecules NAMPT Nicotinamide phosphoribosyltransferase NIBIT Italian network for tumor biotherapy NSCLC Non-small cell lung cancer PMN-MDSC Polymorphonuclear myeloid-derived suppressor cell PDAC Pancreatic ductal adenocarcinoma SIC Società Italiana di cancerologia SIICA Società Italiana di Immunologia, Immunologia Clinica ed Allergologia SITC Society for immunotherapy of cancer TAM Tumor-associated macrophage TIL Tumor-infiltrating lymphocyte TLS Tertiary lymphoid structure TNBC Triple negative breast cancer UDP Uridine diphosphate UTP Uridine triphosphate Acknowledgements This meeting was organized in collaboration with the NIBIT Board of Directors. Author contributions All authors contributed to writing the manuscript. MB collected and assembled contributions from all authors. All authors revised and approved the final version of the manuscript. Funding This meeting was supported in part by unrestricted grants from AstraZeneca, Becton Dickinson (BD), Bristol-Meyers Squibb, Diatech Labline, Fluidigm, Incyte, Merck Sharp & Dome (MSD), Milteny Biotec, Nano String, Novartis, Pierre Fabre Oncology, Promega, and under the auspices of the AIOM, the Associazione Italiana Oncologia Toracica (AIOT), the Fondazione Associazione Italiana per la Ricerca sul Cancro (AIRC), the ACC, the Fondazione Melanoma onlus, the Fondazione Grazia Focacci, the Istituto Oncologico Veneto (IOV), the Fondazione Pezcoller, the SIC, the SIICA, and the Women for Oncology Italy. Declarations Conflict of interest PFF has received honorarium for advisory board participation from: Bristol Meyers Squibb, Novartis, MSD, Pierre Fabre and Roche. VB reports relationship with IoBiotech Aps and Codiak BioScience (personal fees), outside the submitted work. All other authors have no conflict of interest to declare. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. Morad G Helmink BA Sharma P Wargo JA Hallmarks of response, resistance, and toxicity to immune checkpoint blockade Cell 2021 184 5309 5337 10.1016/j.cell.2021.09.020 34624224 2. Landow SM Gjelsvik A Weinstock MA Mortality burden and prognosis of thin melanomas overall and by subcategory of thickness, SEER registry data, 1992–2013 J Am Acad Dermatol 2017 76 258 263 10.1016/j.jaad.2016.10.018 27887797 3. Whiteman DC Baade PD Olsen CM More people die from thin melanomas (1 mm) than from thick melanomas (>4 mm) in Queensland Austr J Invest Dermatol 2015 135 1190 1193 10.1038/jid.2014.452 4. Eggermont AMM Bellomo D Arias-Mejias SM Identification of stage I/IIA melanoma patients at high risk for disease relapse using a clinicopathologic and gene expression model Eur J Cancer 2020 140 11 18 10.1016/j.ejca.2020.08.029 33032086 5. Casucci M Nicolis di Robilant B Falcone L CD44v6-targeted T cells mediate potent antitumor effects against acute myeloid leukemia and multiple myeloma Blood 2013 122 3461 3472 10.1182/blood-2013-04-493361 24016461 6. Noviello M Manfredi F Ruggiero E Bone marrow central memory and memory stem T-cell exhaustion in AML patients relapsing after HSCT Nat Commun 2019 10 1065 10.1038/s41467-019-08871-1 30911002 7. Meric-Bernstam F Larkin J Tabernero J Bonini C Enhancing anti-tumour efficacy with immunotherapy combinations Lancet 2021 397 1010 1022 10.1016/S0140-6736(20)32598-8 33285141 8. Felip E Altorki N Zhou C Adjuvant atezolizumab after adjuvant chemotherapy in resected stage IB-IIIA non-small-cell lung cancer (IMpower010): a randomised, multicentre, open-label, phase 3 trial Lancet 2021 398 1344 1357 10.1016/S0140-6736(21)02098-5 34555333 9. Sezer A Kilickap S Gumus M Cemiplimab monotherapy for first-line treatment of advanced non-small-cell lung cancer with PD-L1 of at least 50%: a multicentre, open-label, global, phase 3, randomised, controlled trial Lancet 2021 397 592 604 10.1016/S0140-6736(21)00228-2 33581821 10. Caruso C Three-drug regimen bests chemo in NSCLC Cancer Discov 2021 10.1158/2159-8290.CD-NB2021-0380 33893148 11. Schmid P Rugo HS Adams S Atezolizumab plus nab-paclitaxel as first-line treatment for unresectable, locally advanced or metastatic triple-negative breast cancer (IMpassion130): updated efficacy results from a randomised, double-blind, placebo-controlled, phase 3 trial Lancet Oncol 2020 21 44 59 10.1016/S1470-2045(19)30689-8 31786121 12. Cortes J Cescon DW Rugo HS Pembrolizumab plus chemotherapy versus placebo plus chemotherapy for previously untreated locally recurrent inoperable or metastatic triple-negative breast cancer (KEYNOTE-355): a randomised, placebo-controlled, double-blind, phase 3 clinical trial Lancet 2020 396 1817 1828 10.1016/S0140-6736(20)32531-9 33278935 13. Bekkering S Arts RJW Novakovic B Metabolic induction of trained immunity through the mevalonate pathway Cell 2018 172 135–146 e9 10.1016/j.cell.2017.11.025 14. Cirovic B de Bree LCJ Groh L BCG Vaccination in humans elicits trained immunity via the hematopoietic progenitor compartment Cell Host Microbe 2020 28 322 34 10.1016/j.chom.2020.05.014 32544459 15. Giamarellos-Bourboulis EJ Tsilika M Moorlag S Activate: Randomized Clinical Trial of BCG Vaccination against Infection in the Elderly Cell. 2020 183 315 323 10.1016/j.cell.2020.08.051 32941801 16. Mitroulis I Ruppova K Wang B Modulation of myelopoiesis progenitors is an integral component of trained immunity Cell 2018 172 147 161 10.1016/j.cell.2017.11.034 17. Kalafati L Kourtzelis I Schulte-Schrepping J Innate immune training of granulopoiesis promotes anti-tumor activity Cell 2020 183 771 785 10.1016/j.cell.2020.09.058 33125892 18. Leader AM Grout JA Maier BB Single-cell analysis of human non-small cell lung cancer lesions refines tumor classification and patient stratification Cancer Cell 2021 39 1594 609 10.1016/j.ccell.2021.10.009 34767762 19. Maier B Leader AM Chen ST A conserved dendritic-cell regulatory program limits antitumour immunity Nature 2020 580 257 262 10.1038/s41586-020-2134-y 32269339 20. Valpione S Mundra PA Galvani E The T cell receptor repertoire of tumor infiltrating T cells is predictive and prognostic for cancer survival Nat Commun 2021 12 4098 10.1038/s41467-021-24343-x 34215730 21. Morello G Cancila V La Rosa M T cells expressing receptor recombination/revision machinery are detected in the tumor microenvironment and expanded in genomically over-unstable models Cancer Immunol Res 2021 9 825 837 10.1158/2326-6066.CIR-20-0645 33941587 22. Kichenadasse G Miners JO Mangoni AA Rowland A Hopkins AM Sorich MJ Association between body mass index and overall survival with immune checkpoint inhibitor therapy for advanced non-small cell lung cancer JAMA Oncol 2020 6 512 518 10.1001/jamaoncol.2019.5241 31876896 23. Strauss L Sangaletti S Consonni FM RORC1 regulates tumor-promoting “emergency” granulo-monocytopoiesis Cancer Cell 2015 28 253 269 10.1016/j.ccell.2015.07.006 26267538 24. Travelli C Consonni FM Sangaletti S Nicotinamide phosphoribosyltransferase acts as a metabolic gate for mobilization of myeloid-derived suppressor cells Cancer Res 2019 79 1938 1951 10.1158/0008-5472.CAN-18-1544 30777853 25. Consonni FM Bleve A Totaro MG Heme catabolism by tumor-associated macrophages controls metastasis formation Nat Immunol 2021 22 595 606 10.1038/s41590-021-00921-5 33903766 26. Zappasodi R Serganova I Cohen IJ CTLA-4 blockade drives loss of Treg stability in glycolysis-low tumours Nature 2021 591 652 658 10.1038/s41586-021-03326-4 33588426 27. Ugolini A Tyurin VA Tyurina YY Tcyganov EN Donthireddy L Kagan VE Gabrilovich DI Veglia F Polymorphonuclear myeloid-derived suppressor cells limit antigen cross-presentation by dendritic cells in cancer JCI Insight 2020 10.1172/jci.insight.138581 32584791 28. Tcyganov EN Hanabuchi S Hashimoto A Distinct mechanisms govern populations of myeloid-derived suppressor cells in chronic viral infection and cancer J Clin Invest 2021 10.1172/JCI145971 34228641 29. Perego M Tyurin VA Tyurina YY Reactivation of dormant tumor cells by modified lipids derived from stress-activated neutrophils Sci Transl Med 2020 10.1126/scitranslmed.abb5817 33268511 30. Manzo T Prentice BM Anderson KG Accumulation of long-chain fatty acids in the tumor microenvironment drives dysfunction in intrapancreatic CD8+ T cells J Exp Med 2020 10.1084/jem.20191920 32491160 31. Flerin NC Cappellesso F Pretto S Mazzone M Metabolic traits ruling the specificity of the immune response in different cancer types Curr Opin Biotechnol 2021 68 124 143 10.1016/j.copbio.2020.10.011 33248423 32. Van Acker HH Ma S Scolaro T Kaech SM Mazzone M How metabolism bridles cytotoxic CD8(+) T cells through epigenetic modifications Trends Immunol 2021 42 401 417 10.1016/j.it.2021.03.006 33867272 33. Dominguez CX Muller S Keerthivasan S Single-cell RNA sequencing reveals stromal evolution into LRRC15(+) myofibroblasts as a determinant of patient response to cancer immunotherapy Cancer Discov 2020 10 232 253 10.1158/2159-8290.CD-19-0644 31699795 34. Purcell JW Tanlimco SG Hickson J LRRC15 is a novel mesenchymal protein and stromal target for antibody-drug conjugates Cancer Res 2018 78 4059 4072 10.1158/0008-5472.CAN-18-0327 29764866 35. Peng J Sun BF Chen CY Single-cell RNA-seq highlights intra-tumoral heterogeneity and malignant progression in pancreatic ductal adenocarcinoma Cell Res 2019 29 725 738 10.1038/s41422-019-0195-y 31273297 36. Mager LF Burkhard R Pett N Microbiome-derived inosine modulates response to checkpoint inhibitor immunotherapy Science 2020 369 1481 1489 10.1126/science.abc3421 32792462 37. Calcinotto A Brevi A Chesi M Microbiota-driven interleukin-17-producing cells and eosinophils synergize to accelerate multiple myeloma progression Nat Commun 2018 9 4832 10.1038/s41467-018-07305-8 30510245
PMC010xxxxxx/PMC10063526.txt	==== Front Gen Hosp Psychiatry Gen Hosp Psychiatry General Hospital Psychiatry 0163-8343 1873-7714 Elsevier Inc. S0163-8343(23)00049-X 10.1016/j.genhosppsych.2023.03.015 Letter to the Editor Pregnant onsite essential workers: Mental health outcomes in a vulnerable population Feldman Natalie abc Koire Amanda ab Mittal Leena ab Erdei Carmina bd Lewis-O'Connor Annie bc Liu Cindy H. abd⁎ a Department of Psychiatry, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA b Harvard Medical School, 25 Shattuck Street, Boston, MA 02115, USA c Department of Medicine, Brigham and Women's Hospital, 75 Francis Street, Boston, MA 02115, USA d Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115, USA ⁎ Corresponding author at: Department of Psychiatry and Department of Pediatric Newborn Medicine, Brigham & Women's Hospital, 221 Longwood Avenue, Boston, MA 02115, USA. 31 3 2023 July-August 2023 31 3 2023 83 196198 21 3 2023 27 3 2023 27 3 2023 © 2023 Elsevier Inc. All rights reserved. 2023 Elsevier Inc. Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Keywords Essential workers Mental health in pregnancy Coping Resilience COVID-19 ==== Body pmcThe COVID-19 pandemic has strained mental health across society, including for essential workers [1], both medical and non-medical. Research suggests that mental health experiences vary across different populations of essential workers, including by gender, direct care of patients with COVID-19, and occupation of the essential worker [2,3]. Essential worker is not a rigorously defined class; for this study, we defined “essential” as anyone who self-reported as an essential worker, not limited to medical personnel. Little is known about pregnant essential workers (PEWs). Pregnancy confers an elevated risk of contracting COVID-19, which has been linked to worse mental health outcomes [4] as well as worse physical outcomes in pregnancy [5]. We theorized that pregnant women who are essential workers could be at particularly high risk of worsened mental health. We further hypothesized that PEWs who worked onsite would have poorer mental health compared to both non-essential workers and non-onsite workers. This study used self-report data from pregnant women collected between May 20, 2020–June 24, 2021 as part of the PEACE Study (see Supplementary Methods). See Table 1 for participant grouping; pregnant individuals were coded as on-site essential personnel if they self-reported as essential and were also going into their workplace. They were coded as non-onsite essential personnel if they self-reported as not essential or if they self-reported as essential but were not going into their workplace. Mood symptoms were assessed by the CES-D and GAD-7 scales, and differences in symptomatology between groups were analyzed while addressing demographic covariates and potential confounders including COVID-19 work risk, social support, past psychiatric history, and psychological factors (see Supplementary Methods).Table 1 Participant grouping. Based on self report. All participants were pregnant at the time of the study. Table 1 Essential worker Not essential worker Working onsite OEWs non-OEWs Not working onsite non-OEWs non-OEWs Prior to analysis, an inspection of variables indicated a normal distribution. Table 2 displays respondents' demographic characteristics. No statistically significant differences were found between OEWs and non-OEWs based on race or rates of pre-existing diagnosis of depression or GAD.Table 2 Demographic characteristics from the PEACE Study among pregnant participants by essential worker and onsite work status, data collected between May 20, 2020 to June 24, 2021. Table 2Key Variables Total (n = 725) Non-essential or not onsite (n = 525) Essential and onsite (n = 200) Chi square or t-tests Means or % Means or % Means or % Essential personnel also working onsite No 72.4% – – Yes 27.6% – – Maternal age (years) M = 32.6, SD = 3.74 M = 32.83, SD = 3.77 M = 32.05, SD = 3.62 t(723) = 2.25, p = .012* Maternal race χ2(4) = 7.28, p = .122 White 91.3% 91.6% 90.5% Black or African American 0.8% 0.6% 1.5% Hispanic or Latino 3.0% 2.5% 4.5% Asian and Pacific Islander 2.6% 2.5% 3.0% Other 2.2% 2.9% 0.5% Maternal education χ2(3) = 11.73, p = .008 Less than college 6.1% 5.9% 6.5% College 29.9% 28.4% 34.0% Masters 42.9% 46.7% 33.0% Doctorate 21.1% 19.0% 26.5% Pregnancy week at the time of survey M = 28.32, SD = 7.63 M = 28.83, SD = 7.74 M = 27.00, SD = 7.20 t(723) = 2.92, p = .004 Pre-existing diagnosis of depression χ2(1) = 0.972, p = .324 No 82.8% 81.9% 85.0% Yes 17.2% 18.1% 15.0% Pre-existing diagnosis of GAD χ2(1) = 0.255, p = .614 No 75.3% 75.8% 74.0% Yes 24.7% 24.2% 26.0% Instrumental support M = 18.33, SD = 2.50 M = 18.22, SD = 2.61 M = 18.63, SD = 2.17 t(723) = −2.00, p = .045* Resilience M = 27.70, SD = 5.86 M = 27.34, SD = 5.84 M = 28.66, SD = 5.85 t(723) = −2.73, p = .006 Distress tolerance M = 3.60, SD = 0.81 M = 3.58, SD = 0.82 M = 3.66, SD = 0.77 t(723) = −1.21, p = .227 Perceived risk for contracting COVID-19 at work M = 0.89, SD = 1.07 M = 0.49, SD = 0.87 M = 1.95, SD = 0.800 t(723) = −20.61, p < .001* Days between survey completion and pandemic start M = 141.66, SD = 70.29 M = 134.55, SD = 64.69 M = 160.33, SD = 80.45 t(723) = −4.47, p < .001*** Fig. 1 displays differences in reported depressive and anxiety symptoms based between OEWs and non-OEWs. Based on the unadjusted model, OEWs showed significantly lower levels of CES-D (p < .001) and GAD-7 (p < .03) scores compared to non-OEWs. These differences remained significant after adjusting for covariates (CES-D: p = .001; GAD-7: p = .003). Covariates positively associated with both CES-D and GAD-7 scores at a statistically significant level (p < .05) include gestational age of the fetus, pre-existing GAD diagnosis, instrumental support (also known as tangible support), resilience, and distress tolerance. Perceived risk of contracting COVID-19 at work was associated with higher GAD-7 scores (p < .001), but not with higher CES-D scores (p = .08). Pre-existing depression diagnosis and when the survey was completed within the pandemic period were not associated with either CES-D or GAD-7 scores.Fig. 1 Adjusted means testing of depressive and generalized anxiety symptoms among pregnant women from the PEACE Study, obtained from May 20, 2020 and June 24, 2021. Error bars reflect SD. OEW = onsite essential worker; non-OEW = non-onsite and/or non-essential worker. p = .001. *p = .003. Fig. 1 Contrary to our hypothesis, we found that OEWs in this sample experienced fewer depressive and anxiety symptoms than non-OEWs. This was true even when controlling for instrumental support, resilience, and distress tolerance. This finding joins research that suggests a complex relationship between essential worker status and mental health. Some studies have found worse mental health among essential workers, including healthcare workers [2] and non-healthcare workers [6]. However, other studies have found different results, such as a study in Australia [3] which found that healthcare workers had less depression and anxiety than both non-healthcare essential workers and the general population. These studies suggest that not all essential types of work confer equivalent mental health risk. Other studies in this area largely distinguished between essential and non-essential, or healthcare and non-healthcare, rather than onsite versus remote within essential workers. There may be a protective aspect to being an OEW, such as diminished isolation, behavioral activation, or informal exposure therapy. Additionally, OEWs may have been relatively insulated from concerns about job security. Finally, having a sense of purpose can be emotionally protective [7]; the OEWs in this study may have derived a sense of meaning from providing an essential service during a pandemic. It is also possible that the category of OEW includes multiple distinct groups. OEWs in this sample reported both service industry jobs and white-collar jobs. This variability is relevant considering education level may influence pregnancy-specific anxiety during the pandemic [8]. Additional research may focus on which areas of onsite essential work are protective for mental health. Selection bias may be at play as this sample is largely White and higher SES, and experience of safety and meaning at work may vary by SES. Women with higher anxiety or depression may have sought exemptions from onsite work, which would affect these findings. Finally, given that the mental health costs of trauma may not emerge until after the acute stressor [9], it is possible that a longitudinal study would find different outcomes. Overall, this data suggests that essential worker mental health remains complex. While pregnancy and essential worker status convey different risks, some pregnant OEWs have better mental health than pregnant non-OEWs. The findings of this study also highlight that essential worker is a heterogeneous category; further research is warranted into which factors are protective for essential workers. Funding This work was supported by the Mary A. Tynan Faculty Fellowship, NIMH under Grant NIMH K23 MH 107714-01 A1 (to C.H.L.), the Family Health and Resilience Fund, and the HMS Dupont Warren and Livingston Fellowships. Declaration of Competing Interest The authors have no disclosures to report. Appendix A Supplementary data Supplementary material: Supplementary Methods Image 1 Acknowledgements We are grateful to Ga Tin Finneas Wong for assistance in the data collection and preparation of this manuscript. Appendix A Supplementary data to this article can be found online at https://doi.org/10.1016/j.genhosppsych.2023.03.015. ==== Refs References 1 Holmes E.A. O’Connor R.C. Perry V.H. Tracey I. Wessely S. Arseneault L. Multidisciplinary research priorities for the COVID-19 pandemic: a call for action for mental health science Lancet Psychiatry 7 6 2020 547 560 10.1016/S2215-0366(20)30168-1 32304649 2 Pappa S. Ntella V. Giannakas T. Giannakoulis V.G. Papoutsi E. Katsaounou P. Prevalence of depression, anxiety, and insomnia among healthcare workers during the COVID-19 pandemic: a systematic review and meta-analysis Brain Behav Immun 88 2020 901 907 10.1016/j.bbi.2020.05.026 32437915 3 Toh W.L. Meyer D. Phillipou A. Tan E.J. Van Rheenen T.E. Neill E. Mental health status of healthcare versus other essential workers in Australia amidst the COVID-19 pandemic: initial results from the collate project Psychiatry Res 298 2021 113822 10.1016/j.psychres.2021.113822 4 Godleski S.A. Harris C.T. Fitzpatrick K.M. Kothari A. Social and behavioral vulnerability, pregnancy, and negative mental health outcomes in the U.S. during the Covid-19 pandemic. AIMS Public Health 9 2 2022 Feb 21 331 341 10.3934/publichealth.2022023 [PMID: 35634033; PMCID: PMC9114785] 5 Twanow J.E. McCabe C. Ream M.A. The COVID-19 pandemic and pregnancy: impact on mothers and newborns Semin Pediatr Neurol 42 2022 100977 10.1016/j.spen.2022.100977 6 Chowdhury N. Kainth A. Godlu A. Farinas H.A. Sikdar S. Turin T.C. Mental health and well-being needs among non-health essential workers during recent epidemics and pandemics Int J Environ Res Public Health 19 10 2022 5961 10.3390/ijerph19105961 35627494 7 Schaefer S.M. Morozink Boylan J. van Reekum C.M. Lapate R.C. Norris C.J. Ryff C.D. Purpose in life predicts better emotional recovery from negative stimuli PloS One 8 11 2013 e80329 10.1371/journal.pone.0080329 8 Moyer C.A. Compton S.D. Kaselitz E. Muzik M. Pregnancy-related anxiety during COVID-19: a nationwide survey of 2740 pregnant women Arch Womens Ment Health 23 6 2020 757 765 10.1007/s00737-020-01073-5 32989598 9 McFarlane A.C. The long-term costs of traumatic stress: intertwined physical and psychological consequences World Psychiatr 9 1 2010 3 10 10.1002/j.2051-5545.2010.tb00254.x
PMC010xxxxxx/PMC10069823.txt	==== Front Value Health Reg Issues Value Health Reg Issues Value in Health Regional Issues 2212-1099 2212-1102 International Society for Health Economics and Outcomes Research. Published by Elsevier Inc. S2212-1099(23)00022-5 10.1016/j.vhri.2023.02.004 Economic Evaluation Cost of Illness in Patients With COVID-19 Admitted in Three Brazilian Public Hospitals Oliveira Layssa Andrade MSc 1 Lucchetta Rosa Camila PhD 23 Mendes Antônio Matoso PhD 4 Bonetti Aline de Fátima PhD 1 Xavier Cecilia Silva 2 Sanches Andréia Cristina Conegero PhD 5 Borba Helena Hiemisch Lobo PhD 6 Oliota Ana Flávia Redolfi MSc 5 Rossignoli Paula MSc 7 Mastroianni Patrícia de Carvalho PhD 2 Venson Rafael PhD 8 Virtuoso Suzane PhD 5 de Nadai Tales Rubens PhD 9 Wiens Astrid MSc, PhD 6∗ 1 Postgraduate Program in Pharmaceutical Science, Federal University of Paraná, Curitiba, Brazil 2 School of Pharmaceutical Sciences, São Paulo State University, Araraquara, Brazil 3 Sustainability and Social Responsibility, Hospital Alemão Oswaldo Cruz, São Paulo, Brazil 4 Clinics Hospital Complex of the Federal University of Paraná, Curitiba, Brazil 5 Center for Medical and Pharmaceutical Sciences, State University of Western Paraná, Cascavel, Brazil 6 Pharmacy Department, Federal University of Paraná, Curitiba, Brazil 7 Department of Pharmaceutical Assistance, Paraná State Health Department, Curitiba, Brazil 8 School of Medicine, Dentistry and Nursing, University of Glasgow, Glasgow, Scotland, UK 9 Department of Public Health, Faculty of Dentistry of Bauru, São Paulo State University, Bauru, Brazil ∗ Correspondence: Astrid Wiens, MSc, PhD, Department of Pharmacy, Federal University of Paraná, Av. Lothário Meissner, 632, 80210-170, Jardim Botânico, Curitiba, Brazil. 3 4 2023 7 2023 3 4 2023 36 3443 7 2 2023 © 2023 International Society for Health Economics and Outcomes Research. Published by Elsevier Inc. 2023 International Society for Health Economics and Outcomes Research Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Objectives The severity and transmissibility of COVID-19 justifies the need to identify the factors associated with its cost of illness (CoI). This study aimed to identify CoI, cost predictors, and cost drivers in the management of patients with COVID-19 from hospital and Brazil’s Public Health System (SUS) perspectives. Methods This is a multicenter study that evaluated the CoI in patients diagnosed of COVID-19 who reached hospital discharge or died before being discharged between March and September 2020. Sociodemographic, clinical, and hospitalization data were collected to characterize and identify predictors of costs per patients and cost drivers per admission. Results A total of 1084 patients were included in the study. For hospital perspective, being overweight or obese, being between 65 and 74 years old, or being male showed an increased cost of 58.4%, 42.9%, and 42.5%, respectively. From SUS perspective, the same predictors of cost per patient increase were identified. The median cost per admission was estimated at US$359.78 and US$1385.80 for the SUS and hospital perspectives, respectively. In addition, patients who stayed between 1 and 4 days in the intensive care unit (ICU) had 60.9% higher costs than non-ICU patients; these costs significantly increased with the length of stay (LoS). The main cost driver was the ICU-LoS and COVID-19 ICU daily for hospital and SUS perspectives, respectively. Conclusions The predictors of increased cost per patient at admission identified were overweight or obesity, advanced age, and male sex, and the main cost driver identified was the ICU-LoS. Time-driven activity-based costing studies, considering outpatient, inpatient, and long COVID-19, are needed to optimize our understanding about cost of COVID-19. Keywords cost analysis cost of illness COVID-19 hospital care hospital costs ==== Body pmcIntroduction COVID-19 remains a pandemic, according to the World Health Organization. In the week between June 20 and 26, 2022 the cumulative number of cases reached 541 million worldwide, with 6.3 million cases progressing to death. In recent weeks, on average new cases have increased again; this increase reached 47% in the Eastern Mediterranean Region.1 These numbers demonstrate that caution is still needed when dealing with COVID-19 and there is a potential for us to live with the disease for the unforeseeable future. Therefore, knowing the implications and costs of this disease remains important. During the first pandemic wave, the Brazilian Society of Infectious Diseases estimated that 80% to 85% of the cases of the disease were mild and did not require hospitalization. In contrast, among the 15% to 20% of cases that required hospitalization, almost a third of inpatients needed intensive care unit (ICU),2 given that the infection can progress to acute respiratory distress syndrome, severe pneumonia, acute respiratory failure, multiple organ failure, and death.3 Because of this, it is believed that patients with COVID-19 present a high cost to the health system. Therefore, determining the costs involved in managing the disease, in addition to identifying the different cost components, provides very useful information and valuable data for the elaboration of complete economic evaluation.4 To date, only one Brazilian study has reported the costs associated with patients with COVID-19. Nevertheless, these data were reported only from a single hospital perspective and not multiple centers.5 The objective of this study was to perform a cost of illness (CoI) analysis of patients with confirmed COVID-19 from 2 perspectives, hospital and the Brazil’s Public Health System (SUS, for its acronym in Portuguese), and to create a predictor model for the costs related to SARS-CoV-2 through the correlation of clinical and sociodemographic factors. Methods Study Design This was a multicenter, retrospective, noncomparative, and analytical observational study with data collection from medical records and hospitalization reports of individuals hospitalized with COVID-19 in 3 Brazilian public hospitals. Costs were considered from the hospital perspective and from the SUS perspective. The checklists Strengthening the Reporting of Observational Studies in Epidemiology6 and Consolidated Health Economic Evaluation Reporting Standards7 were used to report the study. This study was approved by the Research Ethics Committee of the Clinics Hospital Complex of the Federal University of Paraná (CAAE 32 022 720.7.1001.0102). Settings The data collected came from individuals hospitalized in 3 Brazilian public hospitals: the Clinics Hospital Complex of the Federal University of Paraná, a federal hospital, with a capacity of 440 beds, being considered a large size hospital; the Americo Brasiliense State Hospital of the University of São Paulo, a state hospital, with a total of 104 beds; and the University Hospital of the Western of Paraná, a state hospital, with 279 beds, being considered a large size hospital. Medical records of patients diagnosed of COVID-19 who were admitted to the study hospitals between March 1 and September 30, 2020 were evaluated. Participants All patients admitted to one of the study hospitals diagnosed of COVID-19 were included. The following patients were excluded from the study: (1) patients with suspected, but not confirmed, COVID-19; (2) patients whose medical records were not available; (3) patients who did not reach the outcome (hospital discharge or death) during the study period; and (4) patients who were transferred to another hospital before reaching the primary outcome. Additionally, patients without hospital admission authorization were excluded from analyses from the SUS perspective. Variables Hospital discharge and death before discharge were considered the primary outcomes, given that they defined the end of hospital care. Cost of hospitalization, medications, procedures, and other health resources were considered secondary outcomes and were used as indicators of patient care costs. Clinical, imaging, serology, and real-time reverse transcription polymerase chain reaction (RT-PCR) were considered for the diagnosis of COVID-19, as recommended by the Brazilian Ministry of Health.8 Data Sources/Measurement Data from each patient were collected from their respective medical records, from the admission in COVID-19 care units to the hospital discharge or death before discharge; they included (1) sociodemographic data (ie, age, sex, self-declared color), (2) comorbidities (ie, diabetes mellitus [DM], chronic kidney disease, hypertension, asthma, chronic obstructive pulmonary disease, dyslipidemia, overweight or obesity, smoking, immunodeficiency, hypothyroidism), (3) resources (ie, medication, materials, laboratory tests, mechanical ventilation [MV] and noninvasive ventilation [NIV], tracheostomy, hemodialysis, enteral nutrition and imaging tests), and (4) clinical outcome (ie, hospital discharge or death before discharge). Clinical data were identified through the patient’s history present in the medical report. In addition to medical reports, body mass index (BMI) and/or weight and height were collected, whenever available. BMI was calculated for all patients with available data, and the variable “overweight or obesity” was adjusted for patients whose BMI did not match what had been reported, considering the World Health Organization’s definition of overweight and obesity (BMI ≥ 25 kg/m2 and ≥ 30 kg/m2, respectively).9 Nevertheless, for data collection and analysis purposes, patients were grouped into a single group (overweight or obesity). Length of stay (LoS) in the emergency room, ward, or ICU was extracted from each patient’s hospital admission reports. Medications and materials were extracted from the medication/materials reports, whereas the laboratory tests performed were extracted from the billing reports by patient. Costs from the perspective of the SUS were collected using a bottom-up microcosting approach,10 , 11 being extracted individually from the reports of hospital admission authorization of each patient. Costs from the hospital perspective were collected using bottom-up and top-down (aggregated cost technique) microcost approaches.10 , 11 The bottom-up microcosting technique10 , 11 was used to measure the costs of drugs and imaging examinations. For hospital 2 and hospital 3, hemodialysis cost per patient was also available, whereas for hospital 1 the costs of laboratory tests per patient were available. The top-down microcosting technique10 , 11 was used to identify personnel costs, apportionment of costs from other administrative and auxiliary/support cost centers (ie, distribution of various overhead items, in proportion to the department, such as hygiene and cleaning service, MV, concierge, security, laundry, sterilization, infection, nutrition, and dietetics, in addition to hemodialysis for the hospital 1), general costs (water, energy, telephone, building maintenance and contracts for non-medical outsourced services, such as security, in addition to services provided by the foundation for the hospital 1), and materials (hospital medical supplies, cleaning and hygiene, and gas for hospital use). The top-down costs10 , 11 were calculated considering the ratio of the total monthly cost, related to the type of accommodation (ward or ICU) by the number of patient-days, being then multiplied by the number of days that each patient was hospitalized in the respective accommodation and in the respective month. For the hospital 2, the estimated costs using the top-down microcosting technique10 , 11 were calculated using the monthly average of the hospital 3 costs for the ward and ICU and multiplied by the number of days of hospitalization for each patient. This imputation was necessary because these data were missing for this hospital. Study Size All individuals hospitalized for COVID-19 and who met the eligibility criteria were included, with no sampling technique being used. Data Analysis The analysis of CoI for both perspectives, SUS and hospital, was performed using only direct medical costs, defined as all resources that are consumed during treatment or intervention, generated by the use of health services.10 The analysis was performed to identify and measure aggregated and disaggregated costs related to COVID-19, cost drivers (most influential cost components per admission), and cost predictors (sociodemographic and clinical variables) per patients. Top-down costs (aggregated by accommodation and month) were apportioned by patients considering the ratio of the total monthly cost of a given type of accommodation (ward or ICU) to the number of patient-days, result that was multiplied by the number of days that each patient was hospitalized in the respective accommodation, as well as varying according to the month. To identify the total cost for each patient, the costs obtained by top-down were added to the costs obtained by bottom-up. All costs were converted into US$ according to the study period (March to September), in which US$1 corresponded, on average, to R$5.31.12 Statistical Analysis For the descriptive analyses, the continuous variables were described according to the frequency of distribution, measured through the central tendency. Thus, variables with parametric distribution were reported as mean and SD, whereas those with nonparametric distribution were reported as median and interquartile range 25% to 75%, defined using Shapiro-Wilk normality tests. Binary or categorical variables were expressed as number of cases and percentage. Nonparametric tests were performed to compare costs between subgroups: Mann-Whitney U test was used for binary variables (sex, comorbidities, outcome, resources used) and Kruskal-Wallis test was used for variables with 3 or more categories (hospital of study, age group, self-declared color, overweight or obesity, pregnant, and LoS). Given that data collection was performed from medical records, the report of comorbidities was collected as “yes” or “not reported”; not reported was used as the absence of comorbidities was not a reliable information. Additionally, missing data were treated as “not reported.” Univariate and multivariate analyses were performed using a gamma-type generalized linear regression model with log-link function. Univariate analyses were used to verify the variables of significance to be included in the multiple models, and the level of significance for the variable to be included in the multivariate model was 10%, in addition to the event having occurred in at least 10% of the total population. Collinearity between the different variables was defined using clinical criteria, as well as the variance inflation factor (VIF); variables with VIF > 4 showed collinearity and were included in the multivariate model together as interaction variables. Two multivariate regressions were performed. The first regression included only baseline characteristics and aimed to identify the predictors cost increase at the time of patient admission. The second model included resources use in addition to the baseline characteristics; it aimed to identify the cost drivers of COVID-19. All statistical analyses were performed using IBM SPSS Statistics v.26 (SPSS Inc, Chicago, IL). The default significance level considered in the analyses for statistical significance was 2-tailed P values α ≤ .05. Data Availability The individual data collected and the statistical analysis report are available in the public repository The Open Science Framework.13 Results Considering the period between March 1 and September 30, 2020 1084 patients met the inclusion criteria and were included in this study, which corresponds to a total of 1114 admissions in the hospital perspective; of these, 1067 patients (1090 admissions) were included in the SUS perspective (Fig. 1 ). All patients tested positive for SARS-CoV-2 by RT-PCR or serology, in addition to clinical evaluation and/or imaging examinations suggestive of COVID-19.Figure 1 Flowchart of COVID-19 patients included in the study. AIH indicates hospital admission authorization; SUS, Brazil’s Public Health System. Missing data occurred only for the sex of 3 patients (0.3%) and self-declared color of 28 patients (2.6%). Average age was 56 (± 17.2) years (N = 1084); the proportion of males was statistically higher (55.4%; N = 1084). Hypertension was the most prevalent comorbidity, followed by overweight or obesity and DM (Table 1 ).Table 1 Sociodemographic and clinical characteristics and comparison of direct medical costs per individual hospitalized for COVID-19, from March to September 2020. Characteristic n (%) SUS cost (US$), median (IQR) P value n (%) Hospital cost (US$), median [IQR] P value Total 1067 (100) 389.53 [308.17-2135.84] 1084 (100) 1423.38 [688.30-3469.12] Hospital Hospital 1 158 (14.8) 388.10 [310.57-916.10] .000∗ 158 (14.6) 3903.97 [1607.76-7509.96] .000∗ Hospital 2 253 (23.7) 727.53 [315.69-2504.87] 256 (23.6) 1777.22 [1012.97-4095.55] Hospital 3 656 (61.5) 334.54 [289.66-2414.58] 670 (61.8) 1033.46 [506.51-2325.74] Age 0-34 121 (11.3) 315.10 [286.07-1814.76] .000∗ 121 (11.2) 1038.34 [459.77-2379.85] .000∗ 35-44 140 (13.1) 327.24 [296.33-1206.18] 143 (13.2) 1376.66 [585.30-2989.42] 45-54 221 (20.7) 320.13 [303.98-1235.66] 224 (20.7) 1137.55 [573.47-2546.00] 55-64 243 (22.8) 352.40 [299.32-2363.68] 248 (22.9) 1418.52 [811.45-3443.04] 65-74 188 (17.6) 754.56 [311.76-2731.83] 192 (17.7) 1811.05 [738.09-5086.72] 75-84 115 (10.8) 938.73 [319.52-2762.50] 117 (10.8) 2204.95 [963.76-4459.23] ≥ 85 39 (3.7) 1266.93 [451.91-2438.36] 39 (3.6) 1687.56 [932.79-3484.95] Sex† Female 474 (44.5) 333.36 [297.18-1560.08] .004∗ 480 (44.3) 1366.09 [584.27-2815.22] .003∗ Male 590 (55.5) 521.01 [309.37-2432.38] 601 (55.4) 1530.15 [783.95-3992.07] NR 3 (0.3) 308.17 [284.62-4937.52] 3 (0.3) 732.43 [316.58-7031.48] Self-declared color† White 834 (78.2) 387.35 [300.83-2155.56] .774 848 (78.2) 1368.99 [669.86-3419.95] .008∗ Yellow 7 (0.7) 402.62 [284.88-3988.41] 8 (0.7) 876.73 [483.20-3692.72] Brown 69 (6.5) 549.91 [314.15-1266.93] 69 (6.4) 2086.79 [1181.97-6463.02] Black 130 (12.2) 332.47 [294.44-2125.65] 131 (12.1) 1515.40 [693.40-2836.80] NR 27 (2.5) 328.50 [310.25-2174.08] 28 (2.6) 1677.56 [707.96-2449.09] Clinical factors Active smoking 66 (6.2) 679.29 [315.35-3364.20] .147 66 (6.1) 2131.75 [860.24-7475.69] .015∗ Asthma 33 (3.1) 325.04 [308.17-1892.85] .543 34 (3.1) 1435.23 [790.56-2881.82] .936 CKD 37 (3.5) 624.47 [336.41-2320.43] .077 39 (3.6) 2494.14 [1029.42-6441.29] .015∗ COPD 67 (6.3) 886.32 [316.55-3210.71] .014∗ 68 (6.3) 1934.67 [1013.88-5792.94] .012∗ DM 309 (29.0) 561.19 [311.11-2162.71] .026∗ 313 (28.9) 1631.57 [932.79-4275.82] .001∗ DSLP 101 (9.5) 451.91 [294.44-2174.08] .887 102 (9.4) 1446.45 [692.76-3594.11] .994 Hypertension 542 (50.8) 626.41 [310.81-2566.67] .000∗ 551 (50.8) 1690.25 [834.19-4252.25] .000∗ Hypothyroidism 110 (10.3) 989.85 [312.96-2710.97] .004∗ 113 (10.4) 1782.16 [838.40-4459.23] .055 Immunodeficiency‡ 72 (6.7) 963.09 [312.96-3412.41] .040∗ 74 (6.8) 2106.18 [964.56-3992.07] .030∗ Overweight/obesity 365 (34.2) 698.53 [312.96-2428.21] .000∗ 368 (33.9) 2136.69 [1081.13-5376.21] .000∗ Pregnancy 19 (1.8) 423.19 [286.07-879.13] .465 19 (1.8) 542.09 [371.76-2046.73] .001∗ Other comorbidities 410 (38.4) 458.69 [309.37-2480.78] .041∗ 420 (38.7) 1661.23 [796.07-3938.79] .000∗ COPD indicates chronic obstructive pulmonary disease; CKD, chronic kidney disease; DM, diabetes mellitus; DSLP, dyslipidemia; HIV, human immunodeficiency virus; IQR, interquartile range; NR, not reported; SUS, Brazil’s Public Health System. ∗ Statistical significance: P < .05. † Variables analyzed with and without the NR category. ‡ HIV, cancer, transplant. When considering cost per patient admitted during the study period, a median cost of US$389.53 was observed for the SUS perspective compared with a median of US$1423.38 for the hospital perspective. When evaluating the costs among different hospitals from the SUS and hospital perspective, hospital 2 and hospital 1 have the highest median costs per patient, respectively (Table 1). In both perspectives, age groups, sex (male), and comorbidities (hypothyroidism, immunodeficiency, chronic obstructive pulmonary disease, overweight/obesity, hypertension, and DM) had significantly different mean costs per patient (Table 1). From the hospital perspective, being pregnant was associated with a lower median cost than pregnancy not reported in female (US$542.09 vs US$1368.84, P = .001), whereas self-declaring brown was associated with a higher median cost (Table 1). Considering the hospital perspective, the median cost per admission (N = 1114) was estimated at US$1385.80 (US$1188 for admissions in ward only and US$3213.94 for admissions comprising ICU). The cost significantly increases as the LoS in the ward or ICU increases. It is important to highlight high cost was identified for patients with “0 day in ward” because most of these patients received intensive care during the entire admission. In addition, resource utilization was associated with an increase in the cost of hospitalizations for patients using enteral therapy, hemodialysis, MV, NIV, and tracheostomy. Additionally, death before discharge was the outcome of 250 admissions (23.1%) and was associated with higher costs (Table 2 ).Table 2 Use of resources and comparison of direct medical costs per admission for COVID-19, from March to September 2020, from hospital perspective. Characteristics n (%) Hospital cost (US$), median [IQR] P value Total 1114 (100) 1385.80 [670.35-3282.51] Hospitalization unit Emergency 152 (13.6) 1208.37 [749.55-2303.03] .219 Ward 903 (81.1) 1188.80 [582.95-2595.86] .000∗ ICU 520 (46.7) 3213.94 [1566.06-6653.45] .000∗ Length of stay in the ward 0 day 211 (18.9) 3009.75 [1116.15-6660.96] .000∗ 1-4 days 457 (41.0) 684.48 [351.15-1416.73] 5-9 days 290 (26.0) 1446.45 [882.10-2476.90] 10-19 days 136 (12.2) 3100.85 [1831.57-6419.83] 20-29 days 13 (1.2) 4960.15 [3527.58-13 218.80] 30-39 days 4 (0.4) 9662.42 [6514.44-15 641.50] 40-49 days 2 (0.2) 17 964.55 [14 591.53-21 337.57] 50-59 days 1 (0.1) 27 768.20 [27 768.20-27 768.20] Length of stay in the ICU 0 day 594 (53.3) 768.68 [399.32-1329.15] .000∗ 1-4 days 167 (15.0) 1444.91 [885.79-2142.74] 5-9 days 135 (12.1) 2542.53 [1636.44-3946.09] 10-19 days 148 (13.3) 5534.06 [3646.42-7926.74] 20-29 days 50 (4.5) 9700.34 [6949.10-13 773.42] 30-39 days 13 (1.2) 12 126.19 [10 647.93-16 974.66] 40-49 days 6 (0.5) 15 773.16 [11 514.48-20 724.59] 50-59 days 0 - 60-69 days 1 (0.1) 36 430.00 [36 430.00-36 430.00] Resources use Enteral therapy 345 (31.0) 5088.75 [2659.45-8509.57] .000∗ Hemodialysis 105 (9.4) 6996.29 [3882.22-10 424.07] .000∗ MV 354 (31.8) 4598.51 [2284.47-8292.15] .000∗ NIV 764 (68.6) 1502.89 [786.36-3533.83] .000∗ Tracheostomy 71 (6.4) 9698.89 [5410.10-16 460.13] .000∗ Outcomes Hospital discharge 864 (77.6) 1092 [542.49-2300.84] .000∗ Death before discharge 250 (22.4) 3420.33 [1545.04-6949.10] ICU indicates intensive care unit; IQR, interquartile range; MV, mechanical ventilation; NIV, noninvasive ventilation. ∗ Statistical significance: P < .05. The main component identified for the composition of the cost from the hospital perspective was cost with professionals (39.0%), followed by apportionment cost (33.7%), costs with materials and medicines (17.8%), hemodialysis (6.3%), imaging examinations (2.1%), and costs with laboratory test (1.0%) (Appendix Fig. S1A,B in Supplemental Materials found at https://doi.org/10.1016/j.vhri.2023.02.004). The main component in the composition of the SUS perspective cost was ICU daily (78.1%), followed by COVID-19 treatment package (15.0%), other costs (2.6%), tomography (1.3%), hemodialysis (1.2%), enteral therapy (0.8%), physiotherapeutic treatment (0.8%), and ultrasonography (0.2%) (Appendix Fig. S2A,B in Supplemental Materials found at https://doi.org/10.1016/j.vhri.2023.02.004). The COVID-19 treatment package corresponds to the amount reimbursed for each patient with a minimum stay of 5 days, comprising the necessary actions for the clinical treatment of the hospitalized patient diagnosed of COVID-19.14 After performing multivariate analyses (Table 3 ), the main predictor of increased cost at admission for the hospital perspective was the patient being overweight or obese (58.4% higher cost), followed by being between 65 and 74 years old (42.9%) and being male (42.5%). Patients with BMI ≤ 25 kg/m2 demonstrated a 67% higher cost; nevertheless, it is not possible to confirm this due to the small number of hospitalizations in this category (7.7%).Table 3 Multivariable regression using a generalized linear model of gamma distribution to adjust variables to create a cost prediction for patients with COVID-19 from a hospital perspective (N = 1084). Variable Beta SE P value OR OR 95% CI Intercept 7.082 0.1019 .000 1190.80 975.21 1454.05 Hospital (vs hospital 3) Hospital 1 0.762 0.0978 .000∗ 2.142 1.768 2.595 Hospital 2 0.234 0.0855 .006∗ 1.264 1.069 1.495 Age (vs ≤ 34 years) 35-44 years −0.095 0.1228 .441 0.910 0.715 1.157 45-54 years −0.004 0.1134 .969 0.996 0.797 1.243 55-64 years 0.225 0.1147 .050∗ 1.252 1.000 1.567 65-74 years 0.357 0.1198 .003∗ 1.429 1.130 1.808 75-84 years 0.272 0.1348 .043∗ 1.313 1.008 1.710 ≥ 85 years 0.084 0.1847 .651 1.087 0.757 1.562 Self-declared color (vs white) Yellow −0.494 0.3495 .157 0.610 0.307 1.210 Brown 0.171 0.1303 .189 1.187 0.919 1.532 Black 0.048 0.0933 .609 1.049 0.874 1.259 Not reported −0.221 0.2051 .281 0.802 0.536 1.198 Sex (vs female) Male 0.354 0.0608 .000∗ 1.425 1.265 1.606 Not reported 0.998 0.6021 .097 2.714 0.834 8.832 Comorbidities (vs “not reported”) DM 0.102 0.0735 .166 1.107 0.959 1.279 Hypertension 0.095 0.0702 .177 1.099 0.958 1.261 Overweight/obesity (yes) 0.460 0.0732 .000∗ 1.584 1.372 1.829 Overweight/obesity (no) 0.513 0.1257 .000∗ 1.670 1.306 2.137 CI indicates confidence interval; DM, diabetes mellitus; OR, odds ratio; SE, standard error. ∗ Statistical significance: P < .05. For the SUS perspective, in the multivariate analysis, the following categories of variables were associated with a significantly increase in costs: being male (37.6% higher cost), being between 65 and 74 years old or 75 and 84 years old (46.5% and 38.7% higher costs, respectively), and being overweight or obese (69.0% increase in costs) (Appendix Table S1 in Supplemental Materials found at https://doi.org/10.1016/j.vhri.2023.02.004). For the multivariate analyses, the hospital was included only to adjust for a likely confounding factor in both perspectives. In the multivariate analysis for hospital perspective, when both baseline and admission variables were included, the main observed cost driver was ICU admission, with patients who stayed between 1 and 4 days in the ICU having 60.9% higher costs than patients who were not admitted to the ICU. The cost increases with the increase in LoS, reaching a prediction of 15 times higher costs for patients who were hospitalized in the ICU between 40 and 49 days than individuals who were not in the ICU. Additionally, men, DM, overweight/obesity, death, NIV, MV with enteral therapy, and hospital 2 predicted a cost increase from 1.1 to 1.7 times (Table 4 ).Table 4 Multivariable regression using a generalized linear model of gamma distribution to adjust the variables to identify the drivers of increased cost for patients with COVID-19 from the hospital perspective (N = 1114). Variable Beta SE P value OR OR 95% CI Intercept 5.916 0.0894 .000 370.843 312.230 441.875 Hospital (vs hospital 3) Hospital 1 0.989 0.0482 .000∗ 2.689 2.447 2.956 Hospital 2 0.464 0.0406 .000∗ 1.590 1.469 1.722 Age (vs ≤ 34 years) 35-44 years 0.102 0.0583 .078 1.108 0.988 1.242 45-54 years 0.026 0.0548 .639 1.026 0.922 1.142 55-64 years 0.083 0.0549 .132 1.086 0.975 1.209 65-74 years −0.068 0.0589 .247 0.934 0.832 1.048 75-84 years 0.014 0.0660 .837 1.026 0.891 1.154 ≥ 85 years −0.010 0.0921 .912 0.990 0.826 1.186 Self-declared color (vs white) Yellow −0.045 0.1680 .790 0.956 0.688 1.329 Brown −0.003 0.0621 .959 0.997 0.883 1.099 Black 0.007 0.0447 .877 1.007 0.922 1.126 Not reported 0.042 0.0954 .661 1.043 0.865 1.257 Sex (vs female) Male 0.103 0.0289 .000∗ 1.108 1.047 1.173 Not reported 0.338 0.2845 .235 1.402 0.803 2.449 Comorbidities (vs not reported) DM 0.105 0.0348 .002∗ 1.111 1.038 1.189 Hypertension −0.013 0.0335 .691 0.987 0.924 1.054 Overweight/obesity (yes) 0.171 0.0587 .003∗ 1.187 1.058 1.332 Overweight/obesity (no) 0.106 0.0594 .074 1.112 0.990 1.249 Outcome (vs hospital discharge) Death before discharge 0.328 0.0605 .000∗ 1.388 1.233 1.563 Length of stay in the ward (vs 0 days) 1-4 days −0.167 0.0574 .004∗ 0.846 0.756 0.947 5-9 days 0.501 0.0636 .000∗ 1.650 1.456 1.869 10-19 days 0.969 0.0696 .000∗ 2.636 2.299 3.021 20-29 days 1.266 0.1494 .000∗ 3.545 2.645 4.751 30-39 days 1.682 0.2503 .000∗ 5.377 3.292 8.782 40-49 days 2.566 0.3463 .000∗ 13.014 6.601 25.658 50-59 days 2.002 0.4778 .000∗ 7.403 2.902 18.885 Length of stay in the ICU (vs 0 days) 1-4 days 0.475 0.0448 .000∗ 1.609 1.473 1.756 5-9 days 0.880 0.0601 .000∗ 2.412 2.144 2.713 10-19 days 1.618 0.0714 .000∗ 5.041 4.383 5.798 20-29 days 2.024 0.0916 .000∗ 7.568 6.324 9.056 30-39 days 2.388 0.1452 .000∗ 10.896 8.198 14.483 40-49 days 2.723 0.2050 .000∗ 15.222 10.185 22.750 50-59 days† - - - - - - 60-69 days 2.479 0.4973 .000∗ 4.503 4.503 31.622 NIV (vs not) NIV 0.217 0.0356 .000∗ 1.243 1.159 1.333 Interaction MV and enteral therapy (vs not)‡ MV with ET 0.169 0.0667 .011∗ 1.185 1.039 1.350 MV without ET −0.190 0.0945 .044∗ 0.827 0.687 0.995 ET without MV 0.031 0.1021 .759 1.032 0.845 1.260 CI indicates confidence interval; DM, diabetes mellitus; ET, enteral therapy; ICU, intensive care unit; MV, mechanical ventilation; NIV, noninvasive ventilation; OR, odds ratio; SE, standard error; VIF, variance inflation factor. ∗ Statistical significance: P < .05. † No patients with ICU stay between 50 and 59 days. ‡ Variables showed collinearity through the VIF test. VIF test showed that MV and enteral nutrition presented collinearity, and these 2 variables were included in the multivariate model as interaction factors; from Table 4, it is possible to observe that the cost driver is MV, given that patients who required enteral nutrition without MV showed no significant cost difference. Patients who required MV without enteral nutrition (34 of 1114) presented a 20% decrease in cost, possibly because these patients, in most cases, died more quickly (26 of 34) or used MV for short period (2 [interquartile range 1-3] days) (Appendix Table S4 in Supplemental Materials found at https://doi.org/10.1016/j.vhri.2023.02.004). For the SUS perspective, the variables included in the multivariate analysis were different, given that only those identified in the hospital admission authorizations were included. The estimated median cost per admission was US$359.78 (US$428.72 for admissions that included the COVID-19 treatment package). COVID-19 ICU stay was associated with the highest costs, reaching a median of US$14 026.81 for patients with a stay between 40 and 49 days (Appendix Table S2 in Supplemental Materials found at https://doi.org/10.1016/j.vhri.2023.02.004). In the multivariate analysis for the SUS perspective, the main cost driver was the COVID-19 ICU stay (Appendix Table S3 in Supplemental Materials found at https://doi.org/10.1016/j.vhri.2023.02.004). Discussion COVID-19 has become a public health problem, being a matter of great concern to managers and health professionals. The first months of the pandemic were the most critical, given the lack of knowledge about the disease, the lack of a treatment options with proven efficacy, and the beginning of vaccine development. To the best of our knowledge, there is no published CoI study with the objective of predicting the cost increase based on available data at patient admission (ie, baseline data). This information may be of great value, because it may help optimizing hospitals budget management. Our study showed that being aged between 55 and 64, 65 and 74, and 75 and 84 years, being male, and being overweight or obese are related to an increase of 25.2%, 42.9%, 31.3%, 42.5%, and 58.4%, respectively, in patient cost. Being overweight or obese was associated with increased patient cost at admission. The worsening of obese patients was shown in a systematic review with meta-analysis where obese patients had a 2.32-fold greater probability of ICU admission and a 2.63-fold greater probability of needing MV and 49% greater risk of death in the adjusted analysis; all these factors were related to increased patient cost.15 A median cost per admission identified was US$1385.80 for the hospital perspective, whereas the median cost of reimbursement made by the SUS (federal portion) was US$360.52, which means that SUS provided a transfer of 26% of the cost spent by the hospital through the hospital admission authorization. Currently, it is known that this cost difference is due to the tripartite distribution of reimbursement in Brazil (ie, reimbursement is shared among the municipal, the state, and the federal governments). The Institute for Applied Economic Research identified that, between 2015 and 2019, federal, state, and municipal governments were responsible for financing 40%, 47%, and 13% of general admissions costs, respectively.16 Within this proportion, there was a gap in the reimbursement that should be investigated in detail. Difference in costs was observed between the hospitals in the study, which may be related to possible differences in the standard of care and in data collection. There was a remarkable difference in the mean cost of the aggregated cost categories from hospital perspective, mainly related to the cost of professionals. From the SUS perspective, the main difference was related to the cost of the ICU daily, which for hospital 1 was not reimbursed how specific COVID-19 UCI daily, but the general ICU daily, which corresponds to 37.5% of the cost of the specific COVID-19 ICU daily. In this context, studies point to the need to develop new methodologies to improve care delivery and avoid wasting already scarce resources. The time-driven activity-based costing method allows for measuring costs with high precision and for identification of processes that can direct actions to improve the quality of care.17 The CoI study conducted at Clinic Hospital of the Faculty of Medicine of the University of São Paulo (HCFMUSP) identified an average cost of US$12 637.42 per admission, almost 10 times higher than the median cost identified in this study (US$1385.80). Nevertheless, HCFMUSP was designated for patients with COVID-19 in critical conditions, whereas the hospitals included in our study had patients with disease severity ranging from mild to critical. Another discrepancy among the studies was that all our patients had diagnostic confirmation, in disagreement with the 17.9% of patients with negative RT-PCR or serology included in the HCFMUSP study. Additionally, 8.5% of patients did not complete care at the study hospital, with 0.6% of patients still hospitalized in the HCFMUSP study. Finally, although it was not possible to assess the correlation of hemodialysis in the patients in our study because only 9.4% of hospitalizations used this resource, 19% of patients in the HCFMUSP study used this resource, which was associated with an increase in the cost of hospitalizations.5 Unlike the study conducted at HCFMUSP, which identified a 24% decrease in cost for patients who died,5 our study identified an increase in cost (38.7%) related to this outcome. This is due to the median LoS in ICU (10 [5-17] days) for our patients who died, corroborated by the fact that LoS was the main driver of high cost. In contrast, a study conducted in Colombia identified a median cost of $1688.00 per patient, in addition to a median cost of $4118.00 for patients hospitalized in the ICU.18 These values are very close to those identified in our analyses. Finally, it is important to highlight that many patients were discharged with recommendations for rehabilitation or treatment for COVID-19-related conditions acquired during the course of the disease, but cost data were only collected from hospital admission to hospital discharge, as the treatment for any COVID-19-related condition was performed in other health units. Thus, long-term outcomes have not been assessed; future research could potentially include costs related to these outcomes, including the ones covered by a scoping review, in which 52 potential long-term outcomes related to COVID-19 were described.19 The inclusion of these costs may increase the cost of the patient, especially those with greater severity of the disease. This study has some limitations. First, data were collected from medical records, which may cause reliability issues with regard to completeness and accuracy of the data collected. Second, some categories of variables presented (age ≥ 85 years, being pregnant, admission to ward, ICU for > 20 days, and hemodialysis) showed significant results, but relied on a small number of patients, which may introduce uncertainty issues due to sample size and, therefore, must be interpreted with caution. Third, new SARS-CoV-2 variants and the development of vaccines have modified the profile of patients with COVID-19 and the severity of the disease.20, 21, 22 This study is valuable in characterizing the first wave of COVID-19 and allowing comparison with future studies that show costs of subsequent waves. Conclusions This multicenter study, including 1084 patients (1114 admissions), showed that predictors of rising cost of admission were being overweight or obese (58.4% higher cost), followed by being between 65 and 74 years old (42.9%) and male (42.5%). In addition, ICU admission was identified as the main cost driver, forecasting costs 15 times higher for patients who were hospitalized between 40 and 49 days than individuals who were not in the ICU. Furthermore, patients who died also showed a 38.8% higher cost than patients who were discharged with an outcome. Time-driven activity-based costing studies, considering outpatient, inpatient, and long COVID-19, are needed to optimize our understanding on cost of COVID-19. Article and Author Information Author Contributions: Concept and design: Oliveira, Lucchetta, Wiens. Acquisition of data:Oliveira, Mendes, Bonetti, Xavier, Sanches, Oliota, Rossignoli, Venson, Wiens. Analysis and interpretation of data:Oliveira, Lucchetta, Mendes, Bonetti, Xavier, Sanches, Borba, Venson, Wiens. Drafting of the manuscript: Oliveira, Borba, de Nadai, Wiens. Statistical analysis: Oliveira. Critical revision of paper: Lucchetta, Mendes, Bonetti, Xavier, Sanches, Borba, Oliota, Rossignoli, Venson, Mastroianni, Wiens. Obtaining funding: Lucchetta, Mastroianni. Supervision:Lucchetta, Wiens. Administrative, technical, and logistic support: Mendes, Mastroianni. Provision of study materials: Bonetti, Rossignoli, Wiens. Conflict of Interest Disclosures: The authors reported no conflicts of interest. Funding/Support: This study was partially funded by the 10.13039/501100002322 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES, Financial Code 001), 10.13039/501100003593 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, n. 07/2020, process 308923 / 2020-0), and Unesp-reitoria (PIBIC reitoria 2020-2021). Role of the Funder/Sponsor: The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; or decision to submit the manuscript for publication. Supplemental Materials Supplemental Materials Acknowledgment The authors thank all the staff members at the Hospital and Clinic Pharmacy at the State University of Western Paraná, Cascavel; members of the Pharmaceutical Care Center at the São Paulo State University, Araraquara; and the employees at the archive at the Clinics Hospital Complex of the Federal University of Paraná, who contributed to the data collection. Supplementary data associated with this article can be found in the online version at https://doi.org/10.1016/j.vhri.2023.02.004. ==== Refs References 1 Coronavirus disease (COVID-19) situation reports. World Health Organization https://www.who.int/emergencies/diseases/novel-coronavirus-2019/situation-reports/ 2 Inform from the Brazilian Society of Infectious Diseases (SBI) on the New Coronavirus (Updated on 03/12/2020). Brazilian Society of Infectology www.infectologia.org.br 3 Chen N. Zhou M. Dong X. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study Lancet 395 10223 2020 507 513 32007143 4 Methodological guidelines: economic evaluation guideline Ministry of Health, Secretariat of Science, Technology and Strategic Inputs, Department of Science and Technology, Brazil https://bvsms.saude.gov.br/bvs/publicacoes/diretrizes_metodologicas_diretriz_avaliacao_economica.pdf 5 Miethke-Morais A. Cassenote A. Piva H. COVID-19-related hospital cost-outcome analysis: the impact of clinical and demographic factors Braz J Infect Dis 25 4 2021 101609 34454894 6 von Elm E. Altman D.G. Egger M. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies PLoS Med 4 10 2007 e296 17941714 7 Husereau D. Drummond M. Augustovski F. Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022 explanation and elaboration: a report of the ISPOR CHEERS II good practices task force Value Health 25 1 2022 10 31 35031088 8 Guidelines for diagnosis and treatment of COVID-19 Ministry of Health, Secretariat of Science, Technology, Innovation and Strategic Inputs in Health – SCTIE, Brazil https://saude.rs.gov.br/upload/arquivos/202004/14140600-2-ms-diretrizes-covid-v2-9-4.pdf 9 Obesity. World Health Organization https://www.who.int/health-topics/obesity#tab=tab_1 10 Methodological guideline: micro-costing studies applied to economic evaluations in health. Ministry of Health, Secretariat of Science, Technology and Strategic Inputs, Department of Science and Technology, Brazil https://rebrats.saude.gov.br/images/Documentos/2022/20220419_diretrizes_microcusteio_15062021.pdf 11 Tan S.S. Microcosting in Economic Evaluations: Issues of Accuracy, Feasibility, Consistency and Generalisability. Optima Grafische Communicatie https://repub.eur.nl/pub/17354/091127_Tan,%20Siok%20Swan.pdf Accessed May 7, 2022. 12 Quotations and bulletins: currency quotation. Central Bank of Brazil - Federal Government https://www.bcb.gov.br/estabilidadefinanceira/historicocotacoes 13 Oliveira L.A. Lucchetta R. Wiens A. Cost of Illness in Patients With COVID-19 of Three Brazilian Public Hospital. Public Health Sctland https://publichealthscotland.scot/repository/cost-of-illness-in-patients-with-covid-19-admitted-in-three-brazilian-public-hospitals/ 14 Ordinance No. 245, of March 24, 2020: Includes Procedure in the Table of Procedures, Medications, Orthoses, Prostheses and Special Materials of the SUS, for Exclusive Care of Patients With a Clinical Diagnosis of COVID-19 and Changes the Inform System. Ministry of Health, Brazil https://bvsms.saude.gov.br/bvs/saudelegis/saes/2020/prt0245_15_06_2020_rep.html 15 Huang Y. Lu Y. Huang Y.M. Obesity in patients with COVID-19: a systematic review and meta-analysis Metabolism 113 2020 154378 16 Health accounts from the perspective of international accounting: SHA account for Brazil. Ministry of Health, Brazil. Oswaldo Cruz Foundation, Institute for Applied Economic Research (IPEA) https://www.ipea.gov.br/portal/images/stories/PDFs/livros/livros/220202_livro_contas_de_saude.pdf 17 Etges A.P.B.S. Stefani L.P.C. Vrochides D. Nabi J. Polanczyk C.A. Urman R.D. A standardized framework for evaluating surgical enhanced recovery pathways: a recommendations statement from the TDABC in health-care consortium J Heal Econ Outcomes Res 8 1 2021 116 18 Alvis-Zakzuk N.J. Flórez-Tanus Á. Díaz-Jiménez D. How expensive are hospitalizations by COVID-19? Evidence from Colombia Value Heal Reg Issues 31 2022 127 133 19 Lucchetta R.C. Lemos I.H. Santos A.C.S. Possíveis desfechos de longo prazo da Covid-19: uma revisão sistemática de escopos J Heal Biol Sci 9 1 2021 1 20 Wolter N. Jassat W. Walaza S. Early assessment of the clinical severity of the SARS-CoV-2 omicron variant in South Africa: a data linkage study Lancet 399 10323 2022 437 446 35065011 21 Lin L. Liu Y. Tang X. He D. The disease severity and clinical outcomes of the SARS-CoV-2 variants of concern Front Public Health 9 2021 1929 22 Antonelli M. Penfold R.S. Merino J. Risk factors and disease profile of post-vaccination SARS-CoV-2 infection in UK users of the COVID Symptom Study app: a prospective, community-based, nested, case-control study Lancet Infect Dis 22 1 2022 43 55 34480857
PMC010xxxxxx/PMC10071347.txt	==== Front J Natl Med Assoc J Natl Med Assoc Journal of the National Medical Association 0027-9684 1943-4693 Published by Elsevier Inc. on behalf of National Medical Association. S0027-9684(22)00182-1 10.1016/j.jnma.2022.12.007 Article The impact of COVID-19 on heart failure admissions in Suriname-A call for action Sairras S. a⁎ Baldew S. b Goberdhan C. b van der Hilst K. c Shankar A. d Zijlmans W. e Covert H. f Lichtveld M. f Ferdinand K. g a Scientific Research Center Suriname (SRCS), Academic Hospital Paramaribo (AZP), Suriname b Physical Therapy Department, Faculty of Medical Sciences, Anton de Kom University of Suriname, Paramaribo, Suriname c Thorax Center Paramaribo, Academic Hospital Paramaribo, Suriname d Department of Biostatistics, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA e Faculty of Medical Sciences, Anton de Kom University of Suriname, Paramaribo, Suriname f Department of Environmental Health Sciences, School of Public Health, University of Pittsburgh, Pittsburgh, USA g John W. Deming Department of Medicine, Tulane University School of Medicine, New Orleans, LA, USA ⁎ Corresponding author at: Academic Hospital Paramaribo, Picorni Street 11, Paramaribo, Suriname. 4 4 2023 6 2023 4 4 2023 115 3 283289 16 9 2022 28 10 2022 7 12 2022 © 2023 Published by Elsevier Inc. on behalf of National Medical Association. 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Introduction During the height of the COVID-19 pandemic, there was a worldwide reorganization of healthcare systems focusing on limiting the spread of the virus. The impact of these measures on heart failure (HF) admissions is scarcely reported in Low and Middle Income Countries (LMICs) including Suriname. We therefore assessed HF hospitalizations before and during the pandemic and call for action to improve healthcare access in Suriname through the development and implementation of telehealth strategies. Methods Retrospectively collected clinical (# hospitalizations per patient, in hospital mortality, comorbidities) and demographic (sex, age, ethnicity) data of people hospitalized with a primary or secondary HF discharge ICD10 code in the Academic Hospital Paramaribo (AZP) from February to December 2019 (pre-pandemic) and February to December 2020 (during the pandemic) were used for analysis. Data are presented as frequencies with corresponding percentages. T-tests were used to analyze continuous variables and the two-sample test for proportions for categorical variables. Results There was an overall slight decrease of 9.1% HF admissions (N pre-pandemic:417 vs N during the pandemic: 383). Significantly less patients (18.3%, p-value<0.00) were hospitalized during the pandemic (N: 249 (65.0%)) compared to pre-pandemic (N: 348 (83.3%)), while readmissions increased statistically significantly for both readmissions within 90 days (75 (19.6%) vs 55 (13.2%), p-value = 0.01) and readmissions within 365 days (122 (31.9%) vs 70 (16.7%), p-value = 0.00) in 2020 compared to 2019. Patients admitted during the pandemic also had significantly more of the following comorbidities: hypertension (46.2% vs 30.6%, p-value = 0.00), diabetes (31.9% vs 24.9%, p-value = 0.03) anemia (12.8% vs 3.1%, p-value = 0.00), and atrial fibrillation (22.7% vs 15.1%, p-value = 0.00). Conclusion HF admissions were reduced during the pandemic while HF readmissions increased compared to the pre-pandemic period. Due to in-person consultation restrictions, the HF clinic was inactive during the pandemic period. Distance monitoring of HF patients via telehealth tools could help in reducing these adverse effects. This call for action identifies key elements (digital and health literacy, telehealth legislation, integration of telehealth tools within the current healthcare sector) needed for the successful development and implementation of these tools in LMICs. Keywords Heart failure Hospitalizations COVID-19 Low and middle income countries Suriname ==== Body pmc1 Introduction The COVID-19 pandemic has led to a worldwide reorganization of our society including the healthcare system, most prominently the implementation of several restrictive measures with the aim to limit the spread of the virus.1 Patients with heart failure (HF) are in general already a vulnerable population predisposed to decompensation and hospitalization and are thus at elevated risk for the detrimental effects of the COVID-19 pandemic. These effects can be direct through SARS‑CoV‑2 infection and its associated morbidity and mortality or indirect due to the restrictive measures resulting in a decline of provided physical care within clinical and ambulatory settings.2 Hence, across several European countries, such as the UK,3, 4, 5 Germany,6 Italy7 , 8 and Spain,9 a significant decline in HF hospitalizations has been reported during the COVID-19 pandemic in 2020 compared to the previous year. The same has also been reported in the U.S.A.,10 Argentina,11 Brazil,12 Australia13 and Asia.14 , 15 Additionally, the decline in HF hospitalizations seems to be associated with a higher in-hospital mortality3 , 7 as well as a higher New York Heart Association (NYHA) functional class at admission.6 , 12 In High Income Countries (HICs) especially in North America and Europe, implementation of telehealth including virtual consultations, was strongly recommended, reimbursed, and implemented to ensure continuous ambulatory care.16, 17, 18 Early data on the effects of telehealth tools employed during the first year of the pandemic show that these tools are a viable option for quality healthcare delivery compared to in-person care.16 , 19 There is however little information available regarding the pandemic mitigating measures and the effect of these measures in Low and Middle Income Countries (LMICs) such as Suriname, situated on the northeast coast of South-America. The first case of COVID-19 in Suriname was reported on March 13, 2020, which immediately led to strict governmental rules and regulations to limit the transmission until the end of April 2020, when no more official documented active COVID-19 cases were present in Suriname. In June 2020, the number of active cases increased again in Suriname, reaching a peak in August 2020. During this period, the government introduced a nationwide full lockdown and other social distancing measures in various formats, including no social gatherings, no in-person routine ambulatory care, and promotion of remote school and work methods. During these months, the 6 hospitals in the country operated under special protocols geared to only urgent clinical and outpatient care while the majority of care was directed towards COVID-19 cases. Since telehealth strategies are very scarce and not reimbursed by insurance companies in Suriname, HF patients had limited healthcare access during these months. We therefore hypothesize that admissions for heart failure decreased during the pandemic while readmissions increased. In this context, this study aims to analyze and compare the clinical data of HF hospitalizations in the Academic Hospital Paramaribo (AZP) for the months from February to December 2019 (pre-pandemic) and compared to February to December 2020 (during the pandemic). Furthermore, we make a call for action to improve healthcare access in Suriname through the development and implementation of telehealth strategies. 2 Methods 2.1 Study design and site The Republic of Suriname is a small upper middle income country (Gross Domestic Product, GDP =2.86) situated on the north-east coast of South-America and is part of the Caribbean Community (CARICOM). The 2019 estimated population was 598,000 inhabitants of which 394.000 (65.9%) people are 20 years and older.20 The multiethnic and multicultural population consists mainly of people from African: Creole (15.7%) and Tribal communities (21.7%), and South-Asian: Hindustani (27.4%) and Javanese (13.7%) descent residing mostly in the coastal area, including the capital Paramaribo. The human development index (HDI) is 0.73 and about 70% of the population has at least a basic health insurance. The main economic drivers are the exploitation of natural resources, mainly gold and oil accounting for almost 80% of public sector revenues.21 There are 6 hospitals in Suriname of which 4 reside in the capital Paramaribo. The Academic Hospital Paramaribo (AZP) is the largest hospital in Suriname, situated in the capital Paramaribo, with 530 beds and approximately 26.000 annual admissions. The Thorax Center Paramaribo (TCP), with 34 beds and 2500 annual admissions, is located within the AZP, and serves as the reference cardiac center in Suriname. The Center delivers interventional cardiac care to more than 90% of patients with cardiovascular diseases (CVDs) in Suriname. In 2019, the TCP implemented the HF program aimed at improving HF care. At the core of HF care are regular follow-up outpatient consultations focused on HF education by a trained nurse, and optimization of guideline-directed medical therapy (GDMT) by a cardiologist. Our recent publication on HF admissions shows that there were approximately 1274 HF admissions of which 16% readmissions within the TCP between 2013 and 2015.22 Since then, the number of cardiologists has almost doubled, resulting in a total of 12 cardiologists. 2.2 Data collection For this study, data were retrospectively collected from the medical registry department at the AZP. All hospitalizations with a primary and or secondary International Statistical Classification of Diseases and Related Health Problems (ICD-10) discharge code: I11.0, I13.0, I13.2, and I50.0-I50.9 were retrieved from the administrative electronic health record system. The collected HF patient data include patient demographics (age, sex, residence, and ethnicity), identification number (used to determine number of admissions per patient), admission and discharge date, primary and secondary discharge diagnosis, status after discharge, and all secondary diagnoses. Ethnicity was self-reported and includes Asians: Hindustani, Javanese, and Chinese; African descendants: Creole, and Tribal communities, and Other (Caucasian, Indigenous and Mixed). Exclusion criteria were patients younger than 20 years and those with reversible acute HF secondary to trauma. For our analysis we divided the cohort into 2 groups according to the period. Group 1, the pre-pandemic period, ranging from February 1st- December 31st 2019 and was statistically compared to group 2, Pandemic period, ranging from February 1st- December 31st 2020. The month of January was excluded from analysis since there was no surveillance yet on COVID-19 at that time. 2.3 Study outcomes The primary study outcome is HF admissions during the pandemic period compared to the pre-pandemic period. Secondary outcomes are the admission trend, 30-, 90-day and 1 year HF hospital readmission, length of stay, comorbidities, and in-hospital mortality rate during the 2 periods. 2.4 Data analysis The data were analyzed using Statistical Package for the Social Sciences (SPSS) version 23 (IBM, Chicago, USA). Continuous variables are presented as mean with standard deviation (SD) (parametric analysis) or median (range) (non-parametric analysis). Student's T-test was used for testing statistical significance for the variables age and length of stay (LOS). Categorical variables (all other variables in Table 1 ) are presented as frequencies (N, percentages) and were analyzed for statistical significance using the 2 sample test for proportions. Differences were considered statistically significant when a p-value <0.05 is obtained.Table 1 Primary and secondary HF admissions in the TCP-AZP between February- December 2019 and 2020 Table 1 2019 2020 p-value Hospitalizations, N 417 383 Rate of first admissions per 100,000 pop ≥20 yrs 106 97 ^Hospitalizations versus patients 0.00 Patients, N (%) 347 (83.1) 249 (65.0) Readmissions, N (%) 70 (16.7) 134 (35.0) 0.00 Readmissions <30 days, N (%) 27 (6.5) 36 (9.4) 0.09 Readmissions <90 days, N (%) 55 (13.2) 75 (19.6) 0.01 Readmissions <365 days, N (%) 70 (16.7) 122 (31.9) 0.00 Length of stay 7.2 ± 7.5 6.6 ± 4.7 0.15 ^Gender Female, N (%) 167 (48.1) 125 (50.2) 0.64 ^Age at first admission, M (±SD) 64.9 ± 13.6 63.9 ± 12.7 0.36 ^Ethnicity 0.58 African descent 115 (33.1) 73 (29.3) Asian descent 178 (51.1) 134 (53.8) Other 54 (15.5) 42 (16.9) Risk factors DM 104 (24.9) 122 (31.9) 0.03 HT 128 (30.6) 177 (46.2) 0.00 Anemia 13 (3.1) 49 (12.8) 0.00 AF 63 (15.1) 87 (22.7) 0.00 Mortality, N (%) 8 (1.9) 1 (0.3) 0.03 *Asian descent (Chinese, Hindustani, Javanese), African descent (Creole and Tribal communities), Other (Indigenous, Mixed, Caucasian). ^ These variables are calculated using the number of patients per year. All other variables are calculated using the number of hospitalizations per year.# the 2019 mid-year estimated population of Suriname 20 years and older is 394,000. 3 Results A total of 800 admissions met the inclusion criteria of which 417 were pre-pandemic and 383 during the pandemic, resulting in an overall slight decrease of 9.1% HF admissions (Table 1). The number of patients significantly decreased by 18.3% (347 (83.1%) vs 249 (65.0%), p-value<0.00). In contrast, the number of readmissions increased statistically significantly for both readmissions within 90 days and readmissions within 365 days in 2020 compared to 2019. Patients on average stayed half a day longer in the hospital in 2019 compared to 2020 but this finding was not statistically significant. Table 1 also highlights the significant increase in comorbid admissions with hypertension (HT), diabetes (DM), anemia and atrial fibrillation (AF), all statistically significant more prevalent during the pandemic period compared to pre-pandemic. Figure 1 outlines the number of admissions on a monthly basis for the 2 study periods and shows that admissions decreased by approximately 35% (48 vs 31 admissions) in March 2020 compared to March 2019 and the decrease remained until April 2020. By mid-April 2020, Suriname had zero official documented COVID-19 cases and hospitals started scaling up their admissions, which reflects the influx of admissions at the end of April and May 2020. By June 2020, the government enforced country-wide lockdowns reducing in-person outpatient care. This resulted in a slight admission decrease in June, but an increase in HF admissions in July and August owing to an increase of readmissions (Figure 2 ). The performed logistic regression with the dependent variable readmission showed no significant association for the factors HT, DM, anemia, AF, sex, age, and ethnicity.Figure 1 Monthly HF admissions (N) for 2019 (blue bars) compared to 2020 (orange bars) (left Y-axis). The number of confirmed COVID-19 cases throughout the study period is seen in the grey line (Right y-axis) Figure 1 Figure 2 Percentage of 90-day readmission per month for 2019 (blue bars) and 2020 (orange bars) Figure 2 4 Discussion Our study shows that during the first 10 months of the COVID-19 pandemic, there was an overall drop in HF admissions varying between these months. We also report that especially early in the pandemic, fewer hospitalizations occurred while a significant number of those admissions were HF readmissions. Furthermore, the HF hospitalized patients in 2020 had significantly more comorbidities than those hospitalized in 2019. The increase in readmissions during the pandemic could be the result of several factors. For instance, during the pandemic there was decreased ambulatory care due to the governmental restrictions, leading to less strict monitoring of HF symptoms by healthcare providers. Additionally, studies have reported that patients were more reluctant to seek medical attention during the early months of the pandemic and mostly sought care from the cardiologist when HF symptoms were exacerbated, which then lead to being hospitalized.23 , 24 The study has some limitations that need to be taken into consideration. First, because this is a single center study, assessing only the HF admissions of HF patients does not fully capture the clinical history of these patients during the study period; HF patients are multimorbid which can lead to hospitalizations for their underlying conditions at various departments. Those hospitalizations are not included in this analysis. This may also cause selection bias since we included patients from one department in one hospital. However, with this assessment, we intended to present the impact of HF care disruption at the TCP. Another limitation is the lack of robust clinical and socio-demographic data which could give more insight into factors leading to the increase of readmissions and the state of patients entering the hospital during the pandemic. Furthermore, this is a retrospective analysis and some information that was missing could not be gathered. Further research and data collection may elucidate these questions. A call for action This study highlights the importance of exploring ways to guarantee the monitoring and management of HF patients in Suriname in times of a pandemic. It is well established that remote healthcare delivery via telehealth tools offers a practical solution and has added value in providing customized care for patients with chronic conditions during the pandemic25 , 26 but is also as an additional healthcare tool in the foreseeable future.27 , 28 However, this was not implemented in HF care in Suriname. The TCP implemented the HF care program in 2019 to improve HF care through comprehensive nurse-led consultations and educational sessions and is exploring ways to include telehealth. Telehealth can be valuable in times of a pandemic, but also for patients residing outside greater Paramaribo. These patients could be optimally monitored remotely and provided with the necessary care without extra travel time and costs that a physical appointment in the AZP, in the capital, entails. Analysis of the HF clinical patient population in the TCP show that the majority of patients come from the greater Paramaribo area (the capital Paramaribo and 2 surrounding districts), but that about 20% of HF patients travel from more distant districts for (outpatient) clinical care. Furthermore, care through telehealth can have economic benefits, reduce the pressure on outpatient care and contribute to the health related quality of life (HRQoL) of the HF patients.29 , 30 To offer remote care to our HF patients, thorough research and preparation for implementing these tools in low-income settings are urgently needed and will aid in decreasing worldwide disparities in access to healthcare.31 This can be summarized into a number of action steps.• First, a feasibility study on how care can be offered at a distance whereby the majority of patients can be reached must be conducted. We must examine which tools (e.g., telephone calls, mobile applications, and websites) are most feasible. Additionally, these studies must identify local barriers in order to determine the feasibility of the telehealth tools. • Second, the health professionals who will provide the remote care will need to have the tools, knowledge, and skills to provide care in an efficient and responsible manner and must be willing to use these tools. Our team is currently performing such a study in HF patients and health care workers in the TCP and preliminary findings indicate that most patients are confident that a mobile application, as an eHealth tool, to monitor their HF symptoms and for educational purposes can aid in HF management and healthcare delivery. More than 80% of surveyed patients had access to a smartphone with internet (manuscript in development). • Third, health care institutions and their providers will have to collaborate with health insurers on models to fund this new form of care. • Fourth, this transition requires the commitment of all partners involved in the care of HF patients, ensuring good collaboration between cardiologists, nurses, general practitioners, physiotherapists, dietitians, and social workers to provide complete remote care for HF patients. To realize the above-mentioned actions, developing policies for telehealth legislation, integrating these tools within the current healthcare sector, intensive cooperation between health workers and the ICT sector and addressing socio-demographic inequalities in healthcare delivery are pivotal to successfully implement these tools in our country.32 This proactive strategic roadmap of actions serves as a call to policy makers, healthcare institutions, health professionals, researchers, and governmental and non-governmental organizations to advance remote care specifically in LMICs. The benefits go beyond clinical HF outcomes and ultimately will lead to a more resilient health infrastructure, reducing the stressors on the health services system and ultimately decreasing health care costs. Acknowledgments We would like to thank the medical registration of the AZP for providing the data. Conflicts of Interest: The Authors have no conflict of interests to declare. The research paper was not funded by a grant. ==== Refs References 1 Shereen MA Khan S Kazmi A COVID-19 infection: origin, transmission, and characteristics of human coronaviruses J Adv Res 24 2020 91 98 10.1016/J.JARE.2020.03.005 32257431 2 Charman SJ Velicki L Okwose NC Insights into heart failure hospitalizations, management, and services during and beyond COVID-19 ESC Hear Fail 2020 10.1002/ehf2.13061 3 Cannatà A Bromage DI Rind IA Temporal trends in decompensated heart failure and outcomes during COVID-19: a multisite report from heart failure referral centres in London Eur J Heart Fail 22 12 2020 2219 2224 10.1002/EJHF.1986 32809274 4 Shoaib A Van Spall HGC Wu J Substantial decline in hospital admissions for heart failure accompanied by increased community mortality during COVID-19 pandemic Eur Hear J Qual Care Clin Outcomes 7 4 2021 378 387 10.1093/EHJQCCO/QCAB040 5 Bromage DI Cannatà A Rind IA The impact of COVID-19 on heart failure hospitalization and management: report from a Heart Failure Unit in London during the peak of the pandemic Eur J Heart Fail 22 6 2020 978 984 10.1002/ejhf.1925 32478951 6 König S Hohenstein S Meier-Hellmann A In-hospital care in acute heart failure during the COVID-19 pandemic: insights from the German-wide Helios hospital network Eur J Heart Fail 22 12 2020 2190 2201 10.1002/ejhf.2044 33135851 7 Colivicchi F Di Fusco SA Magnanti M The impact of the coronavirus Disease-2019 pandemic and italian lockdown measures on clinical presentation and management of acute heart failure J Card Fail 26 6 2020 464 465 10.1016/j.cardfail.2020.05.007 32417376 8 Severino P D'Amato A Saglietto A Reduction in heart failure hospitalization rate during coronavirus disease 19 pandemic outbreak ESC Hear Fail 7 6 2020 4182 4188 10.1002/ehf2.13043 9 Gonzalez-Manzanares R Heredia Campos G Fernandez-Aviles Irache C Impact of COVID-19 on heart failure hospitalizations: one year after Eur Heart J 42 Supplement_1 2021 10.1093/eurheartj/ehab724.0839 ehab724.0839 10 Babapoor-Farrokhran S Alzubi J Port Z Impact of COVID-19 on heart failure Hospitalizations SN Compr Clin Med 3 10 2021 2088 2092 10.1007/S42399-021-01005-Z 34189405 11 Burgos LM Villalba L Miranda RMP Impact of COVID-19 pandemic lockdown in decompensated heart failure hospitalizations Int J Hear Fail 3 2 2021 138 10.36628/IJHF.2021.0002 12 Portela MC de Aguiar Pereira CC Lima SML Patterns of hospital utilization in the Unified Health System in six Brazilian capitals: comparison between the year before and the first six first months of the COVID-19 pandemic BMC Health Serv Res 21 1 2021 1 13 10.1186/S12913-021-07006-X/TABLES/2 33388053 13 Toner L Koshy AN Ko J Clinical characteristics and trends in heart failure hospitalizations: an Australian experience during the COVID-19 lockdown JACC Heart Fail 8 10 2020 872 875 10.1016/j.jchf.2020.05.014 14 Ruan X Tan V. Huang W. The impact of COVID 19 on heart failure hospitalization and management from an Asian perspective Eur Heart J 42 Supplement_1 2021 10.1093/EURHEARTJ/EHAB724.0833 15 Choudhary R Mathur R Sharma JB Impact of Covid-19 outbreak on clinical presentation of patients admitted for acute heart failure in India Am J Emerg Med 39 2021 162 10.1016/J.AJEM.2020.10.025 16 Scherrenberg M Frederix I De Sutter J Use of cardiac telerehabilitation during COVID-19 pandemic in Belgium Acta Cardiol 2020 10.1080/00015385.2020.1786625 17 Gorodeski EZ Goyal P Cox ZL Virtual visits for care of patients with heart failure in the Era of COVID-19: a statement from the heart failure society of America J Card Fail 26 6 2020 448 456 10.1016/J.CARDFAIL.2020.04.008 32315732 18 Task Force for the management of COVID-19 of the European Society of Cardiology ESC guidance for the diagnosis and management of cardiovascular disease during the COVID-19 pandemic: part 2-care pathways, treatment, and follow-up Eur Heart J 43 11 2022 1059 1103 10.1093/eurheartj/ehab697 34791154 19 Sammour Y Spertus JA Austin BA Outpatient management of heart failure during the COVID-19 pandemic after adoption of a telehealth model JACC Heart Fail 9 12 2021 916 924 10.1016/J.JCHF.2021.07.003 34857175 20 Department: Population Statistics GBS. Tables of the Publication: Demographic Data 2017 –2019.; 2019. 21 Suriname Overview: Development news, research, data \| World Bank. https://www.worldbank.org/en/country/suriname/overview. Accessed October 19, 2022. 22 Sairras S Baldew SS van der Hilst K Heart failure hospitalizations and risk factors among the multi-ethnic population from a middle income country: the Suriname heart failure studies J Natl Med Assoc 2020 10.1016/j.jnma.2020.08.010 23 Hall ME Vaduganathan M Khan MS Reductions in heart failure hospitalizations during the COVID-19 pandemic J Card Fail 26 6 2020 462 463 10.1016/J.CARDFAIL.2020.05.005 32405232 24 Babapoor-Farrokhran S Alzubi J Port Z Impact of COVID-19 on heart failure hospitalizations[CE: DUPLICATE REFERENCE WITH REF. No. 10. PLEASE CHECK] SN Compr Clin Med 3 10 2021 2088 2092 10.1007/S42399-021-01005-Z 34189405 25 Severino P D'amato A Prosperi S Clinical support through telemedicine in heart failure outpatients during the COVID-19 pandemic period: results of a 12-Months follow up J Clin Med 11 10 2022 10.3390/JCM11102790 26 Galinier M Roubille F Berdague P Telemonitoring versus standard care in heart failure: a randomised multicentre trial Eur J Heart Fail 22 6 2020 985 994 10.1002/EJHF.1906 32438483 27 Zhu Y Gu X Xu C. Effectiveness of telemedicine systems for adults with heart failure: a meta-analysis of randomized controlled trials Heart Fail Rev 25 2 2020 231 243 10.1007/s10741-019-09801-5 31197564 28 Omboni S Padwal RS Alessa T The worldwide impact of telemedicine during COVID-19: current evidence and recommendations for the future Connect Heal 1 2022 10.20517/CH.2021.03 29 Lin M, Yuan W, Huang T, et al. Clinical effectiveness of telemedicine for chronic heart failure : a systematic review and meta-analysis. 2017:1-13. doi:10.1136/jim-2016-000199. 30 Zhu Y Gu X Xu C. Effectiveness of telemedicine systems for adults with heart failure: a meta-analysis of randomized controlled trials[CE: DUPLICATE REFERENCE WITH REF. No. 27. PLEASE CHECK] Heart Fail Rev 25 2 2020 231 243 10.1007/s10741-019-09801-5 31197564 31 Osei E Mashamba-Thompson TP Mobile health applications for disease screening and treatment support in low-and middle-income countries: a narrative review Heliyon 7 3 2021 10.1016/j.heliyon.2021.e06639 32 Ross J Stevenson F Lau R Factors that influence the implementation of e-health: a systematic review of systematic reviews (an update) Implement Sci 11 1 2016 10.1186/S13012-016-0510-7
PMC010xxxxxx/PMC10074353.txt	==== Front Int J Environ Res Int J Environ Res International Journal of Environmental Research 1735-6865 2008-2304 Springer International Publishing Cham 37034128 526 10.1007/s41742-023-00526-w Research Paper Recycling of Anti-COVID-19 Filtering Facepiece Respirators for Use as Preliminary Water Filters Song Uhram 1 http://orcid.org/0000-0002-7794-3475 Kim Jieun [email protected] [email protected] 2 1 grid.411277.6 0000 0001 0725 5207 Department of Biology, Jeju National University, Jeju, 63243 Korea 2 grid.412678.e 0000 0004 0634 1623 Department of Laboratory Medicine, Soonchunhyang University Seoul Hospital, Seoul, 04401 South Korea 5 4 2023 2023 17 3 3528 11 2022 8 2 2023 16 3 2023 © University of Tehran 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Although the United Nations has set sustainable management of water as an important worldwide goal, methods to supply clean water to underdeveloped countries are generally lacking. The ongoing COVID-19 pandemic as increased the worldwide use of filtering facepiece respirators (FFRs), resulting in enormous amounts of plastic waste. The present study tested whether FFRs could be recycled for use as preliminary water filters. Filtering of contaminated water with FFRs significantly reduced its turbidity, as well as concentrations of total organic carbon and major pollutants such as P, K, Mg, and Fe. Most of the filtered samples satisfied the drinking water quality standards of the World Health Organization. The additional use of FFRs decontamination process with hydrogen peroxide or ultraviolet germicidal irradiation, and sterilization with water purification tablets can eliminate disease-causing microorganisms and further reduce turbidity that would make water suitable for drinking. Recycling anti-COVID-19 FFRs for use as preliminary water filters is an effective and sustainable method for solving both drinking water problems and waste due to FFRs. Supplementary Information The online version contains supplementary material available at 10.1007/s41742-023-00526-w. Highlights Anti-COVID-19 filtering facepiece respirators (FFRs) was tested as water filters Filtering contaminated water with FFRs significantly improved water quality FFRs and water purification tablets can make water suitable for drinking Utilizing FFRs as water filters is an effective and sustainable recycling method Supplementary Information The online version contains supplementary material available at 10.1007/s41742-023-00526-w. Keywords Facepiece respirators Drinking water Sustainability Recycling Water quality http://dx.doi.org/10.13039/501100002560 Soonchunhyang University Soonchunhyang University Research Fund Kim Jieun issue-copyright-statement© University of Tehran 2023 ==== Body pmcIntroduction Drinking water quality is one of the greatest factors affecting human health. In many countries, especially in developing countries, drinking water quality is poor, with consumption of poor-quality drinking water inducing many waterborne diseases (Li and Wu 2019). It has been estimated that > 800 children under the age of 5 years die daily from diarrhea caused by dirty water, and that, by 2030, 700 million people worldwide could be displaced by intense water scarcity (Oxfam 2018). One of the most important sustainable development goals developed by the United Nations is to, ‘ensure availability and sustainable management of water and sanitation for all’ (United Nations 2018). Methods to supply adequate amounts of clean water to populations of underdeveloped countries remain inadequate. Water purification tablets containing calcium hypochlorite can sterilize water, eliminating disease-causing microorganisms (ScienceDaily 2013). Sterilized water, however, requires filtration (P and G 2021) to reduce turbidity and the number of floating particles (Kgabi et al. 2014). Much of the drinking water in underdeveloped countries is very turbid (Marobhe et al. 2007), indicating a need for additional filtration. The COVID-19 pandemic has increased the use of masks and respirators for both health workers and non-health-related workers, resulting in the production of enormous amounts of plastic waste (Klemeš et al. 2020; Okoro et al. 2020). Anti-COVID-19 filtering facepiece respirators (FFRs) consist of an inner melt blown (MB) filter made of polypropylene, and an outer layer consisting mostly of synthetic fibers. These plastic materials are difficult to recycle and do not decompose naturally. Although studies have investigated the reuse of these FFRs (Su-Velez et al. 2020; Vernez et al. 2020), many parts of FFRs, including their outside/inside layers, ear bands, and plastic hooks, are difficult to recycle as plastic resources (Battegazzore et al. 2020). Therefore, a fresh point of view for recycling FFR is required. The present study, therefore, assessed whether FFRs could be recycled for use as preliminary water filters. Materials and methods Anti-COVID-19 Filtering Facepiece Respirators (FFRs) N95 anti-COVID-19 FFRs is probably one of the most popular product that is used worldwide (Okoro et al. 2020) that have been reported to collect > 95% of particles under 0.3 μm in size present in air samples (United States National Institute for Occupational Safety and Health) (CDC 2019). The equivalent FFRs in other countries are called FFP2 in the European Union, KN95 in China, DL2 in Japan, and KF94 in South Korea (Liao et al. 2020). KF94 FFRs have been found to collect > 94% of dust particles under 0.4 μm (Park et al. 2020). The N95 and KF94 FFRs utilize the same principle, with MB (Melt Blown) filters in the middle layer filtering out dust and viruses. To avoid product differences between manufacturers, FFRs were purchased from the same company. N95 FFRs were purchased from Kimberly-Clark of the United States (Kimberly-Clark, Irving, Texas, USA), and KF94 FFRs were purchased from Yuhan-Kimberly of South Korea (Yuhan-Kimberly, Seoul, Korea). Dental mask type FFRs with MB filters in the middle layer were also purchased from Yuhan-Kimberly of South Korea. Preparation of Soil–Water Mixtures Soil was collected from a dried puddle at the roadside on Jeju Island, specifically from an area of bare soil without vegetation. After preliminary testing to determine the optimal soil:water ratio, the 2 g soil mixture, consisting of 1.4 g fine soil (sieved with 690 μm sieve) and 0.6 g coarse soil (sieved with 2 mm sieve), was mixed with 1 L water collected from a puddle (total area, 20 m2; maximum water depth, 30 cm) in a rock bed dry stream near Jeju University (Fig. S1 of Supplementary materials). Because people living in underdeveloped countries usually allow particles in collected water to settle out before drinking, the use of highly turbid water samples in this study would exaggerate the turbidity of the water collected in such underdeveloped countries. Thus, the maximum turbidity of the water samples was set at the margin where the bottom of the container became invisible. Filtering System Development and Filtration Three filtering systems were proposed (Fig. S2 of Supplementary materials). The first, a syringe-based filtering system, was composed of a 250 mL syringe, a rubber cap, and a hose clamp. The area used for filtering was about 20 cm2 (diameter, 5 cm), with an additional 1 cm margin required to avoid leaking. The second, a foot pump-based filtering system, was composed of a foot pump, a hose, two 2 L plastic bottles, and one 500 mL plastic bottle. The area used for filtering was about 50 cm2 (diameter, 8 cm) with additional margins of ~ 1–2 cm. The third, a plastic bottle-based filtering system, was composed of a soft (squeezable) plastic bottle and a rubber band. The area used for filtering was about 7.5 cm2 (diameter, 3.1 cm), with an additional 2 cm margin required to avoid leaking. Of the three methods, the syringe filtering system had the least leakage. After adding 2 g soil to 1 L collected water, the samples were mixed thoroughly and filtered with the FFR filtering system. Most samples were filtered with the syringe-based filtering system, although the plastic bottle-based filtering system using a 1 L milk bottle and a 2 L mineral water bottle was also used. Water and Soil Analysis The filtered water was filtered again through Whatman filter paper no. 2 (Whatman plc, Little Chalfont, United Kingdom), and the weight of the soil removed by the filter paper was measured by determining the increase in weight of the dried filter. Carbon (C) and nitrogen (N) contents of the soil were determined using an elemental analyzer (Flash EA 1112; Thermo Fisher Scientific, Waltham, MA, USA). The electroconductivity (EC) and pH of the water samples were measured with an Orion Star A329 portable multiparameter instrument (Thermo Fisher Scientific, MA, USA). To determine total phosphorus (TP), magnesium (Mg), potassium (K), and iron (Fe) contents of water samples, 10 mL aliquots of water were digested with 5 mL of 70% perchloric acid with shaking at 120 rpm for 24 h. These solutions were filtered through filter paper, and the contents of the filtrate were analyzed using an Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) (ICPS-1000IV; Shimadzu, Japan). To assess drinking water quality, total viable bacterial cell counts (TBCC), total viable Escherichia coli cell counts (TECC), biochemical oxygen demand (BOD), turbidity, total organic carbon (TOC), total nitrogen (TN), and SiO2 were analyzed by the Water Quality Analysis Center of the National Instrumentation Center for Environmental Management (NICEM), Korea. Statistical Analysis Differences between two groups were evaluated using the Wilcoxon two-sample test when normality assumptions were violated. Comparisons among three or more groups were assessed by one-way analysis of variance (ANOVA), followed by post hoc Tukey’s studentized range (HSD) test. All statistical analyses were performed using SAS 9.1 software (SAS Institute, Inc., Cary, NC, USA). Differences were considered statistically significant at p < 0.05. Results All types of FFRs and filtering systems tested were found to significantly remove soil from 1000 mL turbid water samples (Table 1). All FFRs showed > 90% filtration efficiency, with syringe-type filtration showing 95% efficiency. Dental masks showed significantly higher amounts of unfiltered soil than N95 and KF94 FFRs, but dental masks were able to filter > 50% of soil from water. Altering the volume filtered to 500 mL or 2000 mL had no effect on filtering efficiency.Table 1 Weight of unfiltered soil remaining in water after filtering Filter Filtering tool Diameter Volume filtered Unfiltered soil (g) N95 Syringe 5 cm 1000 mL 0.11 ± 0.03b N95 Syringe 5 cm 500 mL 0.11 ± 0.01b N95 Milk bottle 3.1 cm 1000 mL 0.21 ± 0.03b N95 Water bottle 2.5 cm 1000 mL 0.20 ± 0.04b KF94 Syringe 5 cm 1000 mL 0.09 ± 0.01b KF94 Syringe 5 cm 500 mL 0.10 ± 0.01b KF94 Syringe 5 cm 2000 mL 0.12 ± 0.00b KF94 Milk bottle 3.1 cm 1000 mL 0.12 ± 0.00b KF94 Water bottle 2.5 cm 1000 mL 0.17 ± 0.01b Dental Syringe 5 cm 1000 mL 0.99 ± 0.06a Data are presented as the mean ± SE of three replicates Means within a column followed by the same letter did not differ significantly (p > 0.05) Syringes had a capacity of 250 mL; milk bottles were plastic with a capacity of 1 L; and dental mask filters were melt blown (MB) filter grade products To normalize all results to filtering of 1000 mL water, soil weights were doubled after filtering of 500 mL and halved after filtering of 2000 mL The soil used for filtering experiments had low concentrations of N (0.03%) and C (1.24%) (Table 2). Jeju Island is a volcanic island with soil composed of volcanic ash, which has lower nutrient and organic matter content than yellow loess (Nanzyo et al. 1993). The ECs of water before and after filtration did not differ significantly, as expected for soils with low nutrient contents (Table 3). While filtering with N95 FFRs increased the pH of water, filtering with KF94 FFRs reduced the pH (Table 3). The concentrations of P, Mg, K, and Fe were significantly lower after than before filtering with both N95 and KF94 FFRs (Table 4). TBCC and TECC values showed large deviations among replicates following filtration, with no significant differences between N95 and KF94 FFRs (Table 5). Similarly, BOD values did not differ significantly between filters. Water turbidity was significantly reduced, by > 85%, by filtration with both N95 and KF94 FFRs (Table 6). Furthermore, TOC values were also significantly reduced by filtration with both N95 and KF94 FFRs (Table 6). However, filtration by FFRs did not significantly alter TN and SiO2 values for these water samples (Table 6).Table 2 Properties of soil used in these experiments Filter C (%) N (%) None 1.24 ± 0.08 0.03 ± 0.00 Data are presented as the mean ± SE of three replicates Table 3 Electro conductivity (EC) and pH of water after filtering Filter Volume filtered EC (μs/cm) pH None* 1000 mL 65.89 ± 1.69 7.22 ± 0.02ab N95 1000 mL 68.50 ± 1.61 7.32 ± 0.03a N95 500 mL 69.25 ± 1.25 7.29 ± 0.02ab KF94 1000 mL 64.44 ± 0.60 7.16 ± 0.03b KF94 500 mL 65.51 ± 0.47 6.99 ± 0.02c Data are presented as the mean ± SE of three replicates Means within a column followed by the same letter did not differ significantly (p > 0.05) None: Unfiltered water samples Table 4 Concentrations of elements in water after filtering Filter Volume filtered TP Mg K Fe None 1000 mL 0.08 ± 0.00a 0.71 ± 0.01a 0.57 ± 0.01a 1.74 ± 0.07a N95 1000 mL 0.02 ± 0.00b 0.31 ± 0.01b 0.45 ± 0.01b 0.35 ± 0.04b N95 500 mL 0.01 ± 0.00b 0.31 ± 0.01b 0.47 ± 0.01b 0.28 ± 0.03b KF94 1000 mL 0.01 ± 0.00b 0.31 ± 0.00b 0.45 ± 0.01b 0.21 ± 0.05b KF94 500 mL 0.01 ± 0.00b 0.29 ± 0.02b 0.45 ± 0.04b 0.19 ± 0.03b Data are presented as the mean ± SE of three replicates Means within a column followed by the same letter did not differ significantly (p > 0.05) None: Unfiltered water samples TP Total phosphorus Table 5 Concentrations of biological indicators in water after filtering Filter TBCC TECC BOD None 105.7 ± 47.2 666.3 ± 468.6 2.7 ± 0.1 N95 25.3 ± 5.2 112.0 ± 30.6 2.0 ± 0.1 KF94 61.0 ± 18.3 116.7 ± 23.3 2.8 ± 0.4 TBCC Total viable bacterial cell counts (colony-forming units [CFU]/mL), TECC Total viable Escherichia coli cell counts (number/100 mL), BOD Biochemical oxygen demand Data are presented as the mean ± SE of three replicates Means within a column followed by the same letter did not differ significantly (p > 0.05) None: Unfiltered water samples Table 6 Concentrations of physio-chemical indicators in water after filtering Filter Turbidity TOC TN SiO2 None 316.7 ± 22.3a 6.4 ± 0.1a 1.6 ± 0.0 3.8 ± 0.1 N95 37.6 ± 3.7b 5.0 ± 0.1b 1.5 ± 0.0 3.5 ± 0.1 KF94 34.1 ± 2.4b 5.4 ± 0.1b 1.5 ± 0.0 3.8 ± 0.1 TOC Total organic carbon, TN Total nitrogen Data are presented as the mean ± SE of three replicates Means within a column followed by the same letter did not differ significantly (p > 0.05) None: Unfiltered water samples *Turbidity (NTU: Nephelometry Turbidity Unit) Discussion Filtering Systems Using syringe-based filtering system with attached FFRs in front of the syringe has several advantages such as tight sealing, rapid filtering, and easy construction. However, syringe-based filtering systems can only filter a maximum of 250 mL water for a time. After filtering 250 mL of water, rubber caps in front of the syringe must be removed and replaced with new pieces of FFRs. Thus, four separate filtering steps were required to filter 1 L water, making this a time-consuming process to pour water through the back of the syringe. However, because this method was the most accurate, with lowest leakage, it was utilized as the standard method for analysis. Filtering with a foot pump was fastest, but constructing the system was very difficult. Thus, this method was not used to analyze water quality. Filtering systems using a 1 L plastic milk bottle were easiest to construct but there was some leakage during filtering, and squeezing the bottle repeatedly made the bottle fragile. However, because this system was easiest to construct and apply, it was used to test the filtering abilities of N95 and KF94 FFRs. Both provided rapid filtering (link to video of filtering: https://youtu.be/-TRKcjBNDxo), and when compared water colors before the filtration and after the filtration were distinctive that filtered water showed much more clear color (Fig. S3 of Supplementary materials). Water and Soil Analysis The filtration efficiency of each FFR was > 90%, with syringe-type filtration having 95% filtration efficiency for removing soil particles (Table 1). After filtration, the water became much clear, indicating that the particles and soil samples suspended in the water had been removed (Fig. S4 of Supplementary materials). Most of these soil and other particles were removed by the MB filter (Fig. S5A of Supplementary materials), with only small amounts remaining after filtration. Most anti-COVID-19 FFRs consist of three or four layers; products made by Kimberly have four layers. The second layer, consisting of the MB filter, is a very dense meshed structure, which is very effective at keeping soil particles from passing through. Very little soil and other particles were present on the third layer, after the MB filter, as most of these particles had been removed by the MB filter (Fig. S5B of Supplementary materials). Dental masks (anti-droplet masks) filtered > 50% of soil from the water, indicating that the filtration efficiency of dental masks containing MB filters was much lower than those of N95 and KF94 FFRs. Because the values of the dental mask were high, the other values of N95 and KF94 FFRs did not differ significantly. N95 milk bottle and N95 water bottle was significantly highest group while KF 94 water bottle was middle group and others are lowest group (Table 1). These differences may be due to the filtering areas, as water bottle used much less area for filtering [half diameter (quarter area) compared to Syringe], the loading of soil and particles to filter can be the reason. However, FFRs cannot be completely sealed when using plastic water and milk bottles with rubber bands. Although tightly holding fingers were used to minimize leaking, leaking became inevitable (link to video of filtering: https://youtu.be/-TRKcjBNDxo). High values may, therefore, be due to leaking, not to the limits of filtration capacity. Because milk bottles with a greater filtering area yielded the same results as water bottles, and syringe filtering of 2 L water had no effect on the results, it seems the volume of water filtered was lower than the filtration capacity of the device. Soil and other particles, however, were markedly reduced after filtration, suggesting that the use of plastic bottles in developing countries lacking sufficient equipment can remove soil and other particles from water. It was difficult to purchase N95 FFRs in Korea, and we’ve lost most of prepared N95 FFRs during testing prototype and practice. Therefore, we could not use N95 FFRs for double volume (2000 ml) test. However, it is likely that the N95 FFRs we used in this study also would not reach their limit with respect to filtration capacity. Because water in puddles used as a water source where undergoing limited water supply usually has many soil particles and characteristics of these soil particles are usually poor and bare, not organic-rich (WorldVision 2016, 2018). Therefore, in this study, we tried to use poor soils without many organic matters for our experiments. As those limited water source areas are usually arid places, with limited vegetation growth. Therefore, we collected soil from dried puddles without vegetation. As a result, the soil samples collected had low contents of N (0.03%) and C (1.2%) (Table 2). Because the soil samples used in the present experiments had relatively low concentrations of N and C, we expected that the concentrations of other elements, such as P and K, would also be low. The EC was not altered by the treatments (Table 3), indicating an absence of ionic substances from these soil samples, even though the water color was altered by filtration (Fig. S4 of Supplementary materials). Filtration of the water samples with N95 FFRs increased the pH, whereas filtration with KF94 FFRs reduced the pH, although both were around pH 7. KF94 FFRs are whiter in color than N95 FFRs, suggesting that the former probably contains a fluorescence brightening agent and that some chemical altered the pH of water. However, because the materials and processes used in manufacturing are proprietary information, we could not determine the reason for the difference in pH between waters filtered by the two FFRs. Still, the pH range of the filtered water was around pH 7, close to neutral range. P, Mg, K, and Fe concentrations were found to be significantly lower after than before filtration (Table 4). Phosphorus triggers eutrophication, which leads to the degradation of drinking water (Wang et al. 2018). Most treatments reduced TP concentration to one-eighth of that in prefiltered water, whereas treatment of 1000 mL water with N95 FFRs reduced the TP concentration to one-fourth of that prior to filtration. Mg in drinking water is a risk factor for cardiovascular diseases (Rylander et al. 1991). Filtration with FFRs reduced Mg concentrations in water to less than one-half that prior to filtration. In nature, K concentrations are low in water, but contamination of water by salts and potassium chloride (detergent) can expose people to high concentrations of K, which cause many side effects (Organization 2009). All the filtration treatments reduced K concentrations in the water by > 20%. Fe is considered an important indicator of water quality (Saha et al. 2018), with FFR filtration reducing the concentrations of Fe to 10–20% of those observed in prefiltered water. The significant reductions in the concentrations of elements analyzed by ICP emission spectrometry could be due in part to the acid digestion. This digestion dissociated elements attached to the soil particles, allowing their detection by ICP. Because elements in unfiltered water can enter the human gastrointestinal tract, their removal by filtration with FFRs may be an important step in the purification of drinking water. Water quality analysis of the microorganisms in these soil-in-water samples showed that different methods of filtration did not result in significant differences in TBCC and TECC values (Table 5). AS TBCC and TECC values had large deviations among replicates, no significant differences were detected. However, the absolute values of TBCC following filtration with N95 and KF94 FFRs were 25% and 60%, respectively, and TECC values following filtration were 20% of their prefiltered values. BOD values did not differ significantly, as mixed soil has low nutrient contents, thus having no effect on the concentrations of dissolved matter in water. The BOD value of prefiltered water was < 3 mg/L, satisfying the requirements for residential water (World Health Organization 2017), and indicating that the water collected from these puddles was not so contaminated. The most important factor degrading the quality of drinking water in developing countries is turbidity, with children drinking muddy water being especially at risk of various diseases (WorldVision 2016, 2018). FFRs significantly reduced the turbidity of water by > 85%. Despite the importance of turbidity to the quality of water, few studies to date have assessed the turbidity of drinking water in developing countries. One study (Marobhe et al. 2007) found that the average turbidity of drinking water in a developing country was around 200 nephelometry turbidity units (NTUs), despite these waters being collected from lakes and reservoirs, not puddles. Because the turbidity of water is very high in places where people must walk for hours to collect water from pools (puddles), filtering this water through FFRs would be a very effective method for managing drinking water. FFRs also significantly reduced the TOC values in our study. Because TOC is positively associated with an increase in pathogens (Williams et al. 2015), FFR-associated reductions in TOC would likely enhance the safety of stored water. In contrast to TOC values, FFRs did not significantly affect TN and SiO2 values. Because the Water Quality Analysis Center of the NICEM does not use a digestion method to analyze water samples, the results obtained for turbid and clear water was not different. Several safety concerns are associated with the use of worn FFRs, including the presence of pathogens, the viability of microorganisms on the mask surface, and the transmissibility of fomites. However, the risk of infection or reactivation of pathogens on FFRs will be reduced by maritime transport, as the surface viability of COVID-19 and other coronaviruses on porous surfaces was reported to be about 72 h (Van Doremalen et al. 2020). The survivability of microorganisms after 48 h on the surface of FFRs is expected to be low (Cho et al. 2014), with maritime transport under dry conditions eliminating most of the risk. To ensure 100% safety, decontamination with microwave heat and high dry heat can also destroy the activities of viruses and other microorganisms. As these processes also result in the degradation of the respirator material (Su-Velez et al. 2020), it is not used. However, as we are not using airborne particle filtration abilities of FFRs, applying such heating methods will not be a problem. Also, treatment with hydrogen peroxide (H2O2) has been shown to successfully remove mold spores and other pathogens without affecting airflow resistance or the fit of filters, and to maintain an initial filter penetration of < 5% (Rempel et al. 2021). Also, ultraviolet germicidal irradiation can effectively decontaminate respiratory viral agents (Yang et al. 2020). Proper sterilization of FFR filters can eliminate contamination problems, allowing the reuse of FFRs. Because we suggest using FFRs as preliminary water filters, mostly to remove suspended particles and soil samples from water, the additional use of water purification tablets can ensure sterilization of the water. Overall, filtering contaminated water with FFRs significantly reduced turbidity, TOC, and major pollutants and indicators, such as P, K, Mg, and Fe. Because the soil used in these experiments was of poor quality, with low C and N contents, results might be more dramatic if soils rich in organic matter and nutrients were used. The World Health Organization (WHO) has set the drinking water quality standard for Fe at 0.3 mg/L (World Health Organization 2017). Most of the treatmentss tested in this study resulted in water with < 0.3 mg/L Fe, although one treatment, of 1000 mL water with N95 FFR, yielded a marginal value. The WHO standard for Mg in drinking water is 0.3 mg/L (World Health Organization 2017). All of the FFR treatments in this study reduced Mg contents below the standard. Also water filtered with FFRs satisfied WHO standards for K (20 mg/L), EC (300 μs/cm), and pH (6.8–8.0) (World Health Organization 2017). The 2017 WHO standard did not set a maximum value for turbidity, but the 1971 WHO standard for turbiity of drinking water was 25 NTUs (Kumar and Puri 2012; Public Health Nigeria 2020). Although filtering water through FFRs reduced turbidity eight-fold, it remained over 25 NTUs. The WHO also set Escherichia coli cell counts at zero (World Health Organization 2017), but these bacteria were detected in filtered water. Therefore, a combination of filtering through FFRs and treatment with water purification tablets to eliminate disease-causing microorganisms could help to generate secure drinking water. Moreover, water purification tablets have some precipitation effects that can reduce turbidity (ScienceDaily 2013), making filtered water more suitable for drinking. Conclusions Utilizing FFRs for preliminary water filtering before treatment with water purification tablets is an effective method for providing clean drinking water to places where access to clean water is difficult. This method does not require complicated techniques or devices: a plastic bottle with a rubber band is sufficient for using FFRs as preliminary water filters. This simple method could save the lives and health of many people who experience intense water scarcity and could help to achieve one of the sustainable development goals of the United Nations, ensuring the availability and sustainable management of water and sanitation for all. In addition, using recycled FFRs could reduce plastic waste and conserve resources. As about USD 22,143 million is expected the face mask market in 2021 (markets and markets, 2020), recycling FFRs is also likely to be of great importance as a pioneering study in finding additional uses for huge economic costs. Thus, recycling anti-COVID-19 FFRs as preliminary water filters is an effective, economical and sustainable method for both providing safe drinking water and eliminating waste associated with FFR production. Supplementary Information Below is the link to the electronic supplementary material.Supplementary file1 (PDF 686 KB) Acknowledgements This work was supported by the Soonchunhyang University Research Fund. Data availability All data generated or analyzed during this study are included in this published article. Declarations Conflict of interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. ==== Refs References Battegazzore D Cravero F Frache A Is it possible to mechanical recycle the materials of the disposable filtering masks? Polymers 2020 12 2726 10.3390/polym12112726 33213008 CDC, C.f.D.C.a.P. (2019) Approved Particulate Filtering Facepiece Respirators. https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part/default.html. Cho I-Y Kang D-W Kang J Hwang H Won J-H Paek WK Seo S-Y A study on the biodiversity of benthic invertebrates in the waters of Seogwipo, Jeju Island, Korea J Asia-Pacific Biodivers 2014 7 e11 e18 10.1016/j.japb.2014.03.003 Kgabi N Mashauri D Hamatui N Utilisation of water purification “Tablets” at Household level in Namibia and Tanzania Open J Appl Sci 2014 4 560 Klemeš JJ Van Fan Y Tan RR Jiang P Minimising the present and future plastic waste, energy and environmental footprints related to COVID-19 Renew Sustain Energy Rev 2020 127 109883 10.1016/j.rser.2020.109883 34234614 Kumar M Puri A A review of permissible limits of drinking water Indian J Occup Environ Med 2012 16 40 44 10.4103/0019-5278.99696 23112507 Li P Wu J Drinking water quality and public health Exposure and Health 2019 11 73 79 10.1007/s12403-019-00299-8 Liao L Xiao W Yu X Wang H Zhao M Wang Q Chu S Cui Y Can N95 facial masks be used after disinfection? And for how many times medRxiv 2020 3099 19 Marobhe NJ Renman G Jacks G The study of water supply and traditional water purification knowledge in selected rural villages in Tanzania Indigenous Knowledge Syst Sustain Develop Relevance for Africa, Tribes and Tribals 2007 1 111 120 Nanzyo M, Dahlgren R, Shoji S (1993) Chemical characteristics of volcanic ash soils. Developments in soil science. Elsevier, pp. 145–187 Okoro OV Banson AN Zhang H Circumventing unintended impacts of waste N95 facemask generated during the COVID-19 pandemic: a conceptual design approach ChemEngineering 2020 4 54 10.3390/chemengineering4030054 Organization WH (2009) Potassium in drinking-water: background document for development of WHO guidelines for drinking-water quality. World Health Organization Oxfam (2018) Water and sanitation Available at: https://www.oxfam.org/en/what-we-do/issues/water-and-sanitation. Park SR Han J Yeon YM Kang NY Kim E Effect of face mask on skin characteristics changes during the COVID-19 pandemic Skin Res Technol 2020 27 554 559 10.1111/srt.12983 33217053 P&G (2021) A simple way to clean water. Available at: https://csdw.org/pg-purifier-of-water-packets/. Public Health Nigeria P (2020) 1971 WHO drinking water standards table. Available at: https://www.publichealth.com.ng/world-health-organization-who-drinking-water-standards-table/. Rempel D Henneman J Agalloco J Crittenden J Consortium ND Hydrogen Peroxide Methods for Decontaminating N95 Filtering Facepiece Respirators Applied Biosafety 2021 26 71 79 10.1089/apb.20.0042 36034688 Rylander R Bonevik H Rubenowitz E Magnesium and calcium in drinking water and cardiovascular mortality Scandinavian J Work Environ Health 1991 17 91 94 10.5271/sjweh.1722 Saha R Dey NC Rahman S Galagedara L Bhattacharya P Exploring suitable sites for installing safe drinking water wells in coastal Bangladesh Groundw Sustain Dev 2018 7 91 100 10.1016/j.gsd.2018.03.002 ScienceDaily (2013) Innovative water purification tablet for developing world. Available at: https://www.sciencedaily.com/releases/2013/02/130208105307.htm. Su-Velez BM Maxim T Long JL St John MA Holliday MA Decontamination methods for reuse of filtering Facepiece respirators JAMA Otolaryngol Head Neck Surg 2020 146 734 740 10.1001/jamaoto.2020.1423 32614377 United Nations U (2018) Ensure availability and sustainable management of water and sanitation for all Available at: https://sdgs.un.org/goals/goal6. Van Doremalen N Bushmaker T Morris DH Holbrook MG Gamble A Williamson BN Tamin A Harcourt JL Thornburg NJ Gerber SI Aerosol and surface stability of SARS-CoV-2 as compared with SARS-CoV-1 N Engl J Med 2020 382 1564 1567 10.1056/NEJMc2004973 32182409 Vernez D Save J Oppliger A Concha-Lozano N Hopf NB Niculita-Hirzel H Resch G Michaud V Dorange-Pattoret L Charrière N Reusability of filtering facepiece respirators after decontamination through drying and germicidal UV irradiation BMJ Glob Health 2020 5 e003110 10.1136/bmjgh-2020-003110 World Health Organization W (2017) Guidelines for drinking-water quality, 4th edition. Available at: https://www.who.int/publications/i/item/9789241549950. Wang C Wu Y Wang Y Bai L Jiang H Yu J Lanthanum-modified drinking water treatment residue for initial rapid and long-term equilibrium phosphorus immobilization to control eutrophication Water Res 2018 137 173 183 10.1016/j.watres.2018.03.018 29549799 Williams K Pruden A Falkinham JO Edwards M Relationship between organic carbon and opportunistic pathogens in simulated glass water heaters Pathogens 2015 4 355 372 10.3390/pathogens4020355 26066310 WorldVision (2016) Water is life. Available at: https://www.youtube.com/watch?v=FK5Z-9sYtLo. WorldVision (2018) Clean water changes everything. Available at: https://www.youtube.com/watch?v=Sk0KlvCUiqA. Yang H Hu J Li P Zhang C Ultraviolet germicidal irradiation for filtering facepiece respirators disinfection to facilitate reuse during COVID-19 pandemic: A review Photodiagn Photodyn Ther 2020 31 101943 10.1016/j.pdpdt.2020.101943
PMC010xxxxxx/PMC10076153.txt	==== Front spalj ALJ Alternative Law Journal 1037-969X 2398-9084 SAGE Publications Sage UK: London, England 10.1177_1037969X231161626 10.1177/1037969X231161626 Articles Rethinking prison visitation for children with incarcerated parents: Lessons from the Australian Capital Territory Cui Joanna 110935 Independent researcher , Australia https://orcid.org/0000-0001-6264-5443 Doyle Caroline Public Service Research Group, School of Business, 590770 UNSW Canberra , Australia Carey Lukas Faculty of Humanities, Arts & Social Sciences, 110924 University of New England , Australia Dr Caroline Doyle, Public Service Research Group, School of Business, University of New South Wales Canberra, Northcott Drive, Campbell ACT 2612, Australia. Email: [email protected] 4 4 2023 6 2023 4 4 2023 48 2 97101 © The Author(s) 2023 2023 Legal Service Bulletin Co-operative This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. Children of incarcerated parents experience a range of vulnerabilities which have led to them being dubbed the ‘invisible victims’ of the criminal justice system. This article discusses the needs of children with incarcerated parents using recent literature describing children’s experiences during prison visitation suspensions caused by the COVID-19 pandemic. We then critically examine the human rights-based communications framework, as well as the challenges faced by children of incarcerated parents, in the Australian Capital Territory (ACT). We recommend corrective services around Australia retain alternative contact methods and consider introducing in-cell communication technology. Children of prisoners parental incarceration human rights in-cell communication COVID-19 typesetterts10 ==== Body pmcThe children of incarcerated parents are often dubbed ‘invisible victims’ of the criminal justice system, given that policy tends to overlook their unique needs. 1 Recently, the inadequacy of policies to support children of incarcerated parents has been acknowledged through parliamentary inquiries in New South Wales (NSW) 2 and Victoria 3 and through the Commissioner for Children and Young People in South Australia. 4 In this article, we discuss how the COVID-19 pandemic had a significant impact on prison communication due to the suspension of face-to-face contact visits and the introduction of non-contact audio-visual link (AVL) ‘visits’. 5 But the pandemic also presented an opportunity for corrective services to see how visits can be adapted in a post COVID-19 world. We argue that correctional service departments should use lessons learnt during the COVID-19 pandemic to make permanent changes to visits to address some of the challenges children face visiting an incarcerated parent and to ultimately address these ‘invisible victims’ of the criminal justice system. This article is structured as follows. First, we discuss the challenges faced by children who experience parental incarceration, focusing on recent and primarily Australian-based literature including research on children’s experiences during the COVID-19 pandemic. Second, we move to our case study of the Australian Capital Territory (ACT), Australia’s only jurisdiction committed to a human rights framework in the operation of its prison, 6 to examine the visits program at the Alexander Maconochie Centre (‘AMC’), the ACT’s adult correctional centre. We reviewed independent reports and qualitative research against publicly available policy documents to identify challenges faced by children of incarcerated parents in this jurisdiction and identify areas of improvement within the visits program. Finally, we recommend that corrective services retain alternative contact methods and also consider introducing in-cell communication technology to address some of the challenges children with incarcerated parents can face. Impacts of COVID-19 on children with incarcerated parents Existing research has established the unique vulnerabilities faced by children who experience parental incarceration. They can experience a range of challenges such as poor mental and physical health outcomes 7 and are at greater risk of experiencing socioeconomic disadvantage and exposure to adverse childhood experiences including violence and household abuse. 8 Aboriginal and Torres Strait Islander children are more likely to experience parental incarceration than non-Aboriginal and Torres Strait Islander children, 9 and are thus particularly at risk. For example, when primary carers, usually mothers, are imprisoned, Aboriginal and Torres Strait Islander children are more likely than non-Aboriginal and Torres Strait Islander children to be taken into out-of-home care and be involved in child protection and youth justice systems. 10 Recently, a study of over 20,000 children in Western Australia (WA) found that parental incarceration significantly raised the likelihood of vulnerability in early development compared with both children whose parents served community orders and children whose parents had no convictions, suggesting that parental incarceration is an independent risk factor for children’s maladjustment. 11 Despite these challenges, there remains a lack of government oversight and recognition of these children in policymaking and judicial decision-making, leading to them being dubbed ‘invisible’ or ‘forgotten victims’. 12 By maintaining communication during imprisonment, such as via telephone, email, mail, or face-to-face visits, children are able to maintain familial ties which have been linked to stronger adjustment outcomes and can be a protective factor against the harms caused by parental imprisonment. 13 Maintaining the familial relationship during incarceration also helps promote parental rehabilitation by reconnecting people in prison with their parenting role and encouraging effective post-release transition. 14 For example, research conducted with Aboriginal and Torres Strait Islander mothers, in NSW and WA prisons, highlighted the importance of maintaining mothering and caregiving responsibilities towards the cultural identity, wellbeing and relationships of both mothers and children. 15 Mothers described the significance of children in shaping their rehabilitation and post-release plans, as well as the trauma of separation and their concerns over their children’s wellbeing while they were incarcerated. 16 The declaration of the COVID-19 pandemic in March 2020 saw prisons worldwide implement restrictions that banned or limited social contact visits to control the spread of COVID-19. 17 Many Australian jurisdictions responded by temporarily ceasing contact visits and implementing interim alternatives such as AVL visits, increased telephone access and, in some cases, socially distanced visits. Emerging research on the impacts of the pandemic on children with incarcerated parents, while limited, has revealed children’s broadly negative responses to the suspension of prison contact visits. For example, children received less contact time with their parents in prison, and telephone and video visits were not suitable for some children’s needs, particularly for younger children and children with disabilities. 18 Flynn et al’s Australian study of 84 caregivers of children with incarcerated parents identified how almost 95 per cent of respondents believed the visiting restrictions had resulted in negative consequences for children. 19 Yet COVID-19 also served as an opportunity for prisons to adapt to new challenges and implement positive changes. The rapid and widespread introduction of AVL visits, while explored by some Australian jurisdictions prior to COVID-19, 20 has been a significant development brought on by the pandemic. Reports on the uptake of AVL visits across Australia have generally been positive, with researchers identifying some challenges, such as issues in accessing appropriate devices and internet connectivity. 21 AVL visits can reduce the time, stress and financial costs of travelling to prison and may even build parenting skills in a manner more developmentally appropriate for children than written or audio-only communication. 22 As we have shown, both research and children’s experiences before and during the COVID-19 pandemic reinforced the importance of prisons having an appropriate visits program to support children with an incarcerated parent. We now move to the ACT to show some of the issues children have experienced visiting an incarcerated parent in this jurisdiction and how the visits program was adapted during the COVID-19 pandemic. The Alexander Maconochie Centre Opened in 2009, the AMC was intended to be a ‘human rights’ prison with a focus on human rights promotion and rehabilitation. 23 The AMC serves as a unique case study as the first, and only, prison in Australia designed to follow a human rights framework, with regularly reviewed and publicly available reports on its compliance with human rights benchmarks. With a clear intention and commitment towards rehabilitation within legislative and policy instruments, the AMC has been described as having the potential to become a ‘national benchmark for correctional services’ 24 and a model which other jurisdictions may learn from and work toward. 25 Encouraging connections with family are benchmarks of rehabilitation and release-preparation under the ACT Standards for Adult Correctional Services, published by the ACT Inspector of Correctional Services. 26 Despite this, there has been little movement towards recognising the experiences of children in the ACT when compared with other jurisdictions. The AMC holds both male and female prisoners, known as detainees, at different classification levels, sentenced and unsentenced (ie, on remand). 27 While the number of children who have a parent in the AMC is unknown, a 2016 Detainee Health and Wellbeing Survey found that, of 98 respondents, 71 per cent reported having children. 28 Research on the experiences of children with an incarcerated parent in the AMC is found in the studies by Saunders and McArthur, 29 Pridmore, Levy and McArthur, 30 and Saunders. 31 Saunders and McArthur interviewed 16 ACT children and young people who had experienced the incarceration of at least one parent. Children self-identified a range of vulnerabilities which they experienced such as housing instability, domestic violence, low educational achievement, mental illness and financial insecurity. 32 Prior to COVID-19 restrictions, the AMC visits policy allowed each detainee two one-hour visits per week. 33 However, research conducted before COVID-19 restrictions identified existing issues with the visits program which had been raised by detainees and their families. For example, detainees raised that the visits schedule was often incompatible with children’s school times, meaning children were forced to choose between visiting parents or participating in extra-curricular activities on weekends. 34 The geographic location of the prison also poses challenges. Children reported travel inaccessibility, noting the limited frequency of buses, indirect routes and inconvenient scheduling. 35 While social telephone calls have and continue to operate as an important non-contact option, research conducted both before and after COVID-19 have identified that prohibitive call rates restrict the number of phone calls that detainees can afford. 36 While the ACT government had agreed to undertake a comparative jurisdictional review of phone service providers for better call rates, 37 the review has failed to achieve a more affordable call fee for detainees. 38 In March 2020, social visits to the AMC were suspended and AVL visits were introduced. These were limited to one 60-minute visit per week for each detainee, and subject to conditions including behaviour, language, volume, clothing and location. 39 Physically distanced, non-contact social visits were introduced in September 2020 on a limited basis, with one adult and one child permitted per visit and restricted to immediate family and partners. Over the following months, restrictions were eased and then tightened again due to increasing cases of COVID-19 in the ACT. As of November 2022, visitors were required to arrive at least an hour before their scheduled visit to undergo rapid antigen testing on-site. This has meant some families must spend a significant portion of the day to attend a visit and some families have been refused visits due to lateness. 40 The public transport route has not been updated to reflect these new entry requirements, meaning visitors may wait almost two hours before their visit and exclude public transport as an option for families attending the earliest visits. The limited AVL availability and lack of alternative communication methods, such as accessible telephone calls or in-cell communication alternatives, continue to pose limitations for family contact during the periods where in-person visits are unavailable. Discussion and conclusion Previous research has acknowledged the harms suffered by children who experience parental incarceration, and the need for policies to support them and protect the family unit. COVID-19 visitation constraints created new challenges and highlighted existing issues, such as restrictive and unsuitable contact schedules and other communication methods being inaccessible. Despite some issues with implementation, the positive responses to AVL visits demonstrate its potential as a long-term contact option. The COVID-19 pandemic has shown how prisons can adapt to alternative contact methods and the potential of AVL visits as a permanent supplementary option. The ACT, Australia’s only jurisdiction committed to a human rights framework in the operation of the prison, has the potential to lead other states and territories in following an approach that recognises the experiences of children, protects family contact and promotes reintegration. Our discussion of the visiting framework in the ACT shows there are significant opportunities for improvement within this jurisdiction, including expanding the accessibility of AVL and the availability of alternative contact methods such as in-cell communication devices for detainees. We see that alternative contact methods would not only contribute to the policy goals of effective detainee reintegration through family contact but would also address some of the challenges that children experience with visiting an incarcerated parent, such as inaccessible visiting times and limited public transport options. Improving access to alternative contact methods would bring the AMC in line with its stated policy goals of promoting human rights and rehabilitation and raise the national standard for corrective services. On a national level, we recommend corrective services see the benefit of in-cell communications technology, such as tablets. The use of tablets is being trialled in NSW prisons with ‘overwhelmingly positive’ feedback from both detainees and prison staff. 41 In-cell technology has also been trialled and supported in Victoria, although this technology is limited to instant messaging services only and not for calls or AVL. 42 Tablets provide opportunities for continuous engagement with family through calls outside standard visiting periods. Together with the benefits of regular communication, tablets can also offer opportunities to support detainees’ post-release transition and re-entry into the community. 43 Now, nearly three years since COVID-19 first shut down prison visits, it remains clear that COVID-19 concerns are continuing to cause ongoing disruptions. In-cell communication is an important tool in maintaining family connections during times where access to visits may be disrupted with short notice by outbreaks of COVID-19 within the prison. The COVID-19 pandemic has presented an opportunity for corrective services to reconsider the needs of children and to address some of the issues experienced both before and during the pandemic. We acknowledge, however, that improving the accessibility to prison communication is only the first step in reconnecting families and supporting children. As the recent parliamentary inquiries have shown, there is significant scope for structural change, such as in decision-making, access to support, and collection of data on parents in prison. Our recommendations on the retention and expansion of alternative contact methods are therefore only initial steps towards improving contact between the ‘invisible victims’ of the criminal justice system and their incarcerated parents. Acknowledgment This work has been adapted from a report by Joanna Cui, completed as part of an internship with Prisoners Aid (ACT) through the Australian National Internships Program. Joanna Cui is an independent researcher and a recent graduate of the College of Law at the Australian National University. Caroline Doyle is a Senior Lecturer in the Public Service Research Group, School of Business at the University of New South Wales Canberra. Lukas Carey is a Lecturer in Criminology in the Faculty of Humanities, Arts and Social Sciences at the University of New England. ORCID iD Caroline Doyle https://orcid.org/0000-0001-6264-5443 Notes The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Joanna Cui undertook the research for this paper as part of an internship with Prisoners Aid (ACT). Caroline Doyle is the President of Prisoners Aid (ACT). Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article. 1 See Chris Trotter et al, The Impact of Incarceration on Children’s Care: A Strategic Framework for Good Care Planning (2016) 5, 19–25, 40–50; Vicky Saunders, ‘“Sins of our Fathers”: The Lived Experiences of Children and Young People with a Parent in Prison’ (PhD thesis, University of Adelaide, 2018) 63–80, 132–134. 2 Committee on Children and Young People, Parliament of New South Wales, Support for Children of Imprisoned Parents in New South Wales (Report No 4/57, June 2022). 3 Legislative Council Legal and Social Issues Committee, Parliament of Victoria, Inquiry into Children Affected by Parental Incarceration (PP No 360, 4 August 2022). 4 Helen Connolly, Commissioner for Children and Young People, South Australia, Join the Dots: Considering the impact of parental incarceration on children and young people (Project Report No 29, April 2022). 5 For example, Catherine Flynn et al, ‘Contact Experiences and Needs of Children of Prisoners before and during COVID-19: Findings from an Australian survey’ (2022) 27(1) Child & Family Social Work 67; Shona Minson and Catherine Flynn, ‘Symbiotic harms of imprisonment and the effect on children’s right to family life’ (2021) 29 International Journal of Children’s Rights 305. 6 Lorana Bartels and Jeremy Boland, ‘Human Rights and Prison: A Case Study from the Australian Capital Territory’ in Leanne Weber, Elaine Fishwick and Marinella Marmo (eds), The Routledge International Handbook of Criminology and Human Rights (Routledge, 2016) 556, 561; Anita Mackay, Towards Human Rights Compliance in Australian Prisons (ANU Press, 2020) 194–196, 299, 310–313. 7 Daragh Bradshaw et al, ‘Longitudinal Associations between Parental Incarceration and Children's Emotional and Behavioural Development: Results from a Population Cohort Study’ (2020) 46(2) Child Care Health and Development 195; Ram Sundaresh et al, ‘Exposure to Family Member Incarceration and Adult Well-being in the United States’ (2021) 4(5) JAMA Network Open e2111821: 1–12. 8 Kristin Turney, ‘Adverse Childhood Experiences among Children of Incarcerated Parents’ (2018) 89 Children and Youth Services Review 218. 9 Australian Institute of Health and Welfare, The Health of Australia’s Prisoners 2018 (Cat No PHE 246, 2019) 14. 10 Human Rights Law Centre/Change the Record Coalition, Over-represented and Overlooked: The Crisis of Aboriginal and Torres Strait Islander Women’s Growing Over-imprisonment (2017) 13; Elizabeth Sullivan et al, ‘Aboriginal Mothers in Prison in Australia: A Study of Social, Emotional and Physical Wellbeing’ (2019) 43(3) Australian and New Zealand Journal of Public Health 241. 11 Megan Bell et al, ‘Using Linked Data to Investigate Developmental Vulnerabilities in Children of Convicted Parents’ (2018) 54(7) Developmental Psychology 1219. 12 See Trotter et al (n 1); Saunders (n 1). 13 Friedrich Lösel, Risk and Protective Factors Associated with the Resettlement of Imprisoned Fathers & their Families (Final Report, January 2012) 82–9, 97, 111–113. 14 For example, Jonathon J Beckmeyer and Joyce A Arditti, ‘Implications of In-Person Visits for Incarcerated Parents’ Family Relationships and Parenting Experience’ (2014) 53(2) Journal of Offender Rehabilitation 129; Meghan M Mitchell et al, ‘The Effect of Prison Visitation on Reentry Success: A Meta-Analysis’ (2016) 47 Journal of Criminal Justice 74. 15 Sullivan et al (n 10); Thalia Anthony, Gemma Sentance and Larissa Behrendt, ‘“We’re Not Being Treated Like Mothers”: Listening to the Stories of First Nations Mothers in Prison’ (2021) 10(3) Laws 74, 76, 81–86. 16 Anthony, Sentance and Behrendt (n 15) 81–86, 89. 17 World Health Organization, ‘Preparedness, Prevention and Control of COVID-19 in Prisons and Other Places of Detention’ (Interim guidance, 15 March 2020). 18 Flynn et al (n 5) 71, 73–76; Minson and Flynn (n 5) 312–315. 19 Flynn et al (n 5) 73. 20 ACT Inspector of Correctional Services, The Care and Management of Remandees at the Alexander Maconochie Centre 2018 (2019) 64 (‘Remand Report’). 21 Committee on Children and Young People (n 2) 41–42; Legal and Social Issues Committee (n 3) 160–164. 22 Elizabeth Skora Horgan and Julie Poehlmann-Tynan, ‘In-Home Video Chat for Young Children and their Incarcerated Parents’ (2020) 14(3) Journal of Children and Media 400; Jacqueline Singer and David Brodzinsky, ‘Virtual Parent-Child Visitation in Support of Family Reunification in the time of COVID-19’ (2020) 2(3) Developmental Child Welfare 153. 23 Bartels and Boland (n 6). 24 Remand Report (n 20) 11. 25 Bartels and Boland (n 6) 564; Mackay (n 6) 202–3, 310–13. 26 ACT Inspector of Correctional Services, ACT Standards for Adult Correctional Services (2019) 6. 27 In the September 2022 quarter, there were 390 detainees in the AMC, with the majority being men (93.1%): Australian Bureau of Statistics, Corrective Services, Australia, September Quarter 2022 (Catalogue No 4512.0). 28 Jesse T Young et al, ACT Detainee Health and Wellbeing Survey 2016: Summary Results (ACT government, 2017) 22–24. 29 Vicky Saunders and Morag McArthur, Children of Prisoners: Exploring the Needs of Children and Young People who have a Parent Incarcerated in the Australian Capital Territory (SHINE for Kids, 2013). 30 William Pridmore, Michael H Levy and Morag McArthur, ‘Slipping Through the Cracks: Examining the Realities of a Child-Friendly Prison System’ (2017) 83 Children and Youth Services Review 226. 31 Saunders (n 1). 32 Saunders and McArthur (n 29); Saunders (n 1). 33 Remand Report (n 20) 59. 34 Ibid 60-61; ACT Inspector of Correctional Services, Healthy Prison Review of the Alexander Maconochie Centre 2019 (November 2019) (‘Healthy Prison Review 2019’) 139–140. 35 Saunders (n 1) 217; Pridmore, Levy and McArthur (n 30). 36 Healthy Prison Review 2019 (n 34) 163; Remand Report (n 20) 54; ACT Inspector of Correctional Services, Healthy Prison Review of the Alexander Maconochie Centre 2022 (November 2022) (‘Healthy Prison Review 2022’) 199–200. 37 Legislative Assembly for the Australian Capital Territory, ‘Government Response to the Report of a Review of a Correctional Centre by the ACT Inspector of Correctional Services: Healthy Prison Review of the Alexander Maconochie Centre 2019’ (2020). 38 Standing Committee on Justice and Community Safety, Legislative Assembly for the Australian Capital Territory, Inquiry into referred 2019–20 Annual and Financial Reports and Budget Estimates 2020-21 Answer to Question on Notice (JACS No 111, 18 March 2021). 39 ACT Corrective Services, Notice to Visitors: COVID-19 (26 March 2020) 40 Healthy Prison Review 2022 (n 35) 205. 41 Bridget Fitzgerald, ‘Tablet Computers have Kept Prisoners in Touch with Family during COVID-19’, ABC News (online, 21 November 2020) https://www.abc.net.au/news/2020-11-21/tablet-computers-to-prisoners-during-covid-19/12895870. 42 Legal and Social Issues Committee (n 3) 171. 43 Aysha Kerr and Matthew Willis, ‘Prisoner Use of Information and Communications Technology’ (2018) 560 Trends and Issues in Crime and Criminal Justice 1, 7–10.
PMC010xxxxxx/PMC10077305.txt	==== Front Pastoral Psychol Pastoral Psychol Pastoral Psychology 0031-2789 1573-6679 Springer US New York 1063 10.1007/s11089-023-01063-1 Article A Theoretical and Theological Reframing of Trauma Holton M. Jan 1 http://orcid.org/0000-0003-4395-9724 Snodgrass Jill L. [email protected] 2 1 grid.26009.3d 0000 0004 1936 7961 Duke Divinity School, Duke University, Box 90965, Durham, NC 27708-0965 United States of America 2 grid.259262.8 0000 0001 1014 2318 Loyola University Maryland, 4501 N. Charles Street, Baltimore, MD 21210 United States of America 6 4 2023 2023 72 3 337351 22 2 2023 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Racism, eco-violence, and myriad sociopolitical and interpersonal injustices continuously injure individuals, communities, and the globe, thereby challenging the human capacity to endure. The prevailing biomedical model of trauma, with its emphasis on pathology, fails to acknowledge the traumatic nature of these diffuse and pervasive injuries. The disciplines of spiritual and pastoral psychology are uniquely poised to reconceptualize trauma and reframe it as part of a stress-trauma continuum, given the way trauma can engender great suffering as well as resistance and the possibility of transformation. This perspective eschews the sentiment, ubiquitous in popular culture, that everything stressful is traumatic as well as the notion that “true” trauma is delimited by the Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR). This article posits a strength-based approach to trauma that contextualizes our societal negativity bias within spiritual values of hope, (post-traumatic) growth, and (possibly) resilience while not diminishing the very real suffering, even despair, that emerge from trauma of all kinds. Keywords Trauma Distress Stress-trauma continuum Theologies of trauma issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcTrauma has many types, and it is variously defined according to differences in discipline and context. Definitions of trauma are intended to describe a phenomenon or lived experience, yet they also inform how humans experience the self, relationships, events, and the world. The American Psychological Association defines trauma, in a general sense, as “an emotional response to a terrible event such as an accident, rape, or natural disaster” (APA, n.d.-c). All aspects of creation, including but not limited to humans, endure terrible events. The pervasiveness of such terrible events seemingly supports the attitude, rather ubiquitous in the United States, that everything stressful is traumatic. Yet, not every terrible event is traumatic simply because it is distressing. Many medical and mental health professionals argue that only experiences that entail “actual or threatened death, serious injury, or sexual violence” constitute real trauma (American Psychiatric Association, 2022). Racism, eco-violence, and myriad sociopolitical and interpersonal injustices continuously injure individuals, communities, and the planet, thereby challenging existence. Even so, the biomedical model of trauma put forth in the DSM-5-TR (APA, 2022), with its emphasis on pathology, fails to acknowledge the traumatic nature of these many diffuse and persistent injuries humans endure. Amid the varying conceptualizations of trauma, the disciplines of spiritual and pastoral psychology are uniquely poised to reconceptualize trauma and reframe it as part of a stress-trauma continuum (Dulmus & Hilarski, 2003), particularly given the way trauma can engender great suffering as well as resistance and even the possibility of transformation. It is important to acknowledge some of the tensions faced in endeavoring to reconceptualize and reframe trauma. At its core, this is an epistemological enterprise that requires more holistic understandings of “how we know what we know” (hooks, 1994, p. 174). It requires thinking more broadly as well as more narrowly about how trauma is defined, but most importantly, thinking differently. Most essential is that we value ways of knowing that are central to non-Western, Black, and Indigenous people and people of color (BIPOC), even if those ways of knowing are in tension with the medicalization of trauma privileged in the United States. While biomedical definitions of trauma are essential for diagnosis and treatment, they are necessarily narrow, limited, and designed to serve the larger biomedical system. Our aim is not to alter how trauma is defined in the DSM-5-TR. Nonetheless, we find it imperative to push against definitions of trauma that fail to acknowledge insidious “terrible events” such as those stemming from racism in the United States or the resilience via resistance that so often co-occurs. The effort to reframe understandings of trauma and push beyond the medical model is rooted in theoretical research as well as empirical research (Bonanno & Mancini, 2012; Frueh et al., 2005; Krupnik, 2019; Marsella et al., 1996; Spoont et al., 2009; van der Kolk et al., 2005). Method and Positionality Pastoral psychology is inherently interdisciplinary. Theorists and practitioners in the field aim to be “bilingual” in the “languages” of psychology and theology/religious studies (Doehring, 2015; Snodgrass, 2015). Questions of how these disciplines are integrated have endured for decades and present epistemological challenges (Townsend, 2009; Barbour, 1990) posited four common methods for managing the epistemic tension between science and religion: conflict, independence, dialogue, and integration. In seeking to reconceptualize and reframe trauma, we employ an integrative method wherein we view psychology and theology/religious studies as allied, mutually informing disciplines. Coherence between the two is possible because knowledge is always both constructed and revealed. The psychological sciences, and some may argue theology, aim for objectivity and neutrality, yet both are culturally informed and constructed. Therefore, we do not place primacy upon biomedical/psychological, nor upon theological/religious wisdom. Rather, we aim to understand how the wisdom from each can be integrated toward a coherent conception of trauma that is both culturally relevant and liberative. Although we take an integrative approach, our religious locations (Greider, 2019), and other aspects of our social identities and lived experience, dispose us to view the psychological with a hermeneutic of hope. As two White, cisgender, heterosexual females, we each experience myriad privileges in the United States. We are both ordained in Christian denominations (Jan in the United Methodist Church and Jill in the United Church of Christ), which biases us toward making deliberative meaning from affliction and seeking hope, practices most surely facilitated in part by our privileges. My (Jan’s) worldview is strongly impacted, personally and professionally, by my research over the years in refugee camps and conflict areas (South Sudan and the Democratic Republic of the Congo) with persons who have experienced war, famine, and violence in many forms. From them I have learned much about what we would call trauma as well as the many ways that people are resilient in the face of circumstances that cause despair. I am resolute in the inclusion of a cultural (and intercultural) lens through which to ask questions of God, faith, and the human predicament. I attempt, though imperfectly to be sure, to live into a vigilant stance of practicing and building social empathy in the world I inhabit. My (Jill’s) perspectives on trauma are influenced, in part, by my own experiences of distress that are often classified in U.S. culture, accurately or not, as traumatic (one example being miscarriage and infertility). My experience teaching undergraduate students amid the COVID-19 pandemic has shown me that the mental health crisis facing youth and emerging adults in the United States is indisputable (U.S. Department of Health & Human Services, 2021), yet students frequently consider their distress to be symptomatic of trauma. Certainly, their psycho-social-emotional development impacts how they appraise and construct their experiences. But culture also seems to support distorted appraisals of distress and coping. Current Cultural Constructions of Trauma Language Matters The use of the term “trauma” to describe personal distress has become so ubiquitous as to cause a recent New York Times opinion editor to ask: If everything is trauma, is anything? (Bennett, 2022). Trauma, much like depression and anxiety, has become a catch-all term for distress. We find ourselves in a vocabulary desert when it comes to words that describe difficult events and the feelings they evoke. What most people today do know, put simply, is that posttraumatic stress disorder (PTSD) is caused by terrible events that the mind cannot wrap itself around. Of course, the clinical language for PTSD and other stressors in the DSM-5-TR is much more complex. Nonetheless, in this current era when extraordinary events seem to be outcompeting themselves, colloquial practice has come to depend heavily on the use of the term trauma to describe these distressing experiences. Our “idioms of distress” have narrowed to the point that any distress can be labeled traumatic (Nichter, 1981). While it is easy to blame the dearth of linguistic agility on popular culture, the truth is much more complicated. Our cultural dependency on trauma language to describe psychological distress has been shaped by decades of increasing dependence on biomedical models for mental illness. In any given culture a variety of ways exist to express distress. Expressive modes are culturally constituted in the sense that they initiate particular types of interaction and are associated with culturally pervasive values, norms, generative themes, and health concerns (Nichter, 1981, p. 379). In the United States, and arguably in most Western societies, we depend on the formula of medical diagnosis, treatment, and cure to address our modern ills, be they physical or mental. The popular perception of and language with which we describe mental disorders have been shaped by these clinical models to such a degree that we have lost our ability to describe them otherwise (Davis, 2020). This trauma language serves to validate suffering of all kinds, particularly that over which we have little control (Fassin & Rechtman, 2009). Yet when our sole language for understanding trauma is bound by this biomedical model, we unnecessarily limit our understanding of which experiences are considered traumatic, what the effects of that trauma might look like in the lived experience, and even to whom (or to what creatures) we may apply the notion of trauma in the first place. Language informs how we construct, narrate, and understand our experiences. bell hooks (1994) noted that “shifting how we think about language and how we use it, necessarily alters how we know what we know” (p. 174). If what we come to know in the context of distressing experiences, especially in uncertain times when one seems to have no control, is consistently constructed as traumatic, it reduces the propensity toward resilience and growth. Naming all our experiences as traumatic can be life-limiting. Paradoxically, biomedical constructions of trauma delimited to events that entail “actual or threatened death, serious injury, or sexual violence” can invalidate the enduring distress that some humans experience in the face of systemic oppression or multiple stresses stemming from ongoing planetary devastation (APA, 2022). In these and other situations, naming such experiences as traumatic can be a life-giving witness to the damage and strain endured. Practicing “language care” is essential to reconceptualizing trauma and reframing it as part of a stress-trauma continuum (Bueckert & Schipani, 2006). Caring for the language we employ and taking care to define that language precisely can be both a pastoral practice (or discipline) and a pastoral intervention. The Seeming Pervasiveness of Trauma In many ways, the COVID-19 pandemic represents a turning point in the human experience of terrible events. Though not experienced on an equal level by all globally, the awareness of the potential for illness, the ever-increasing death toll, and the accompanying deleterious racial, economic, and political repercussions are unparalleled in recent memory, if not beyond. Concurrently, the media and popular culture has magnified the traumatic potential of myriad life experiences, including identifying as LGBTQ+ (LA Blade Digital Staff, 2022), running while Black (Streeter, 2020), gun violence and school shootings (Blake, 2022), interpersonal violence (Hillstrom, 2022), and other terrible events. The traumatic potential of everyday life has, some argue, shaped an entire generation. Maxwell Alejandro Frost, a 25-year-old running for Congress in Florida’s 10th congressional district, told an NPR interviewer, “Our generation [Gen Z] has been born into a lot of trauma and a lot of civil unrest around people being frustrated with things. And I think because of that, our generation naturally thinks about things in a bit of a different way” (Moore, 2022). Assertions such as these are often attempts to witness and honor suffering, but an unintended consequence can be the medicalization or the pathologizing of distress. Over 20 years ago, psychiatrist and philosopher Patrick Bracken (2002) argued against the “trauma industry.” According to Bracken, biomedical conceptualizations of trauma erroneously reify universal truths about terrible events by positing that the mind, regardless of whose mind, will process such events in the same general way. Yet, not all humans’ autonomic nervous systems function the same, and meaning-making is highly subjective and contextual. Humans most often make meaning of distressing events in community, not in isolation. Individuals, families, and communities conceptualize experiences of distress as traumatic in part because such conceptualizations are culturally supported in cultures where distress has been medicalized (White et al., 2017). Individually and collectively, many in the United States, particularly in this current time, seem to be struggling to cope with and manage their emotions of distress. Yet paradoxically, the medicalization of distress contributes to and supports a low tolerance of distress, which ultimately impedes our ability to cope. This is particularly problematic given that “low tolerance to distress is an important predictor of psychopathology and maladaptive health behaviors, including anxiety, depression, substance abuse, eating disorders, and borderline personality disorder,” the experience of which can contribute to our self-appraisal as being “traumatized” (McIntosh et al., 2021, p. 2). The Movement for Global Mental Health (White et al., 2017) and contemporary psychological aid to refugees exemplify the problems Bracken (2002) raised regarding the medicalization of distress. Humanitarian psychiatry has over the last 20 years exported the Western medical model of PTSD and the consequent dependence on trauma language to refugee and internal displacement camps, disaster zones, and conflict areas around the world (Bracken, 2002; Fassin & Rechtman, 2009; Summerfield 1999). Interestingly there is very often a notable absence of an indigenous word for trauma, or even some of the common responses to the effects of traumatic events, in these other cultures. For example, there is no indigenous word for trauma in South Sudan even though they have been engaged in some level of conflict for many decades or longer (Holton, 2011). Rather, as with Arabic words and cultural concepts subsumed into tribal languages, PTSD has likewise been imported to describe the specific clinical symptoms of trauma. It is difficult to believe that a people at war for decades would not have their own words to describe what are considered in the biomedical model to be universal emotions and behaviors associated with the effects of war. Some have made the argument that the South Sudanese were simply unaware of what responses one might expect from the trauma of war, a perspective that negates the wisdom of the culture and fails to embrace the concept that the meaning of such experiences is constructed rather than a foregone outcome of a terrible event like war. The medicalization of distress and the proliferation of the trauma industry are also evident in the qualifications for refugees seeking asylum in the United States. Refugees are required to show evidence of trauma, particularly by means of a psychiatric assessment but also through photographs of wounds and other sources of documentation (Fassin & Rechtman, 2009). This demonstrates not only the medicalization of distress but also its politicization. It is not without some degree of irony that while asylum-seekers are required to be trauma victims to receive asylum, the experiences of many BIPOC, who have endured arguably the greatest degree of racism, violence, and ongoing uncertainty in the United States, do not satisfy cultural or biomedical conceptions of trauma. Whose suffering will be legitimated by being granted or denied the arguable privilege of being deemed trauma induced? What authorities exercise this power, and why is it that everyone is so eager to have their experience validated and thereby be designated a trauma survivor? From Adverse Childhood Experience to Trauma Informed Before presenting psychological and theological conceptions of trauma, it is important to briefly reflect upon how trauma came from the margins to the center of cultural discourse. In 1966, the National Academy of Sciences identified trauma as the most “neglected disease of our society,” rendering trauma a central focal point for research across disciplines (Committee on Trauma and Committee on Shock, 1966). This sentiment set the groundwork for the Adverse Childhood Experiences study, a seminal study conducted from 1995 to 1997 by the Center for Disease Control and Prevention and Kaiser Permanente Health System that resulted in pivotal information about the correlation between the effects of various early life stressors and outcomes later in life. The study has proven indispensable for large-scale public health planning and policy even today. Over the last 20 years, however, the results of the ACE study also have been pushed to the frontlines in medical, social work, and other contexts on an individual level through the use of the ACE-10 questionnaire, a 10-question assessment that attempts to measure the number of specific stressors in childhood. In doing so, advocates for its use imply a causal relationship between early trauma and detrimental effects later in life. Public health researchers have strongly criticized these ACEs screenings, the algorithms used to assess risk, and how they are utilized, saying:[P]rojecting the risk of health or social outcomes based on any individual’s ACE score by applying grouped (or average) risk observed in epidemiologic studies can lead to significant underestimation or overestimation of actual risk; thus, the ACE score is not suitable for screening individuals and assessing risk for use in decision making about need for services or treatment [and further,] although the health conditions listed within the [ACE score] algorithm have been associated with ACEs in epidemiologic studies, most occurrences of many listed conditions are caused by factors other than ACEs. (Anda et al., 2020, pp. 293–294) The ACE study has also raised the question of how to train professionals to be aware of significant stressors, including trauma, in the lives of those to whom they offer services. From this has emerged a trauma-informed paradigm that now shapes the training of professionals across multiple disciplines, including healthcare, social work, church, and education, to name a few. Harris and Fallot (2001), early leaders in trauma informed mental health practice, advocate for “administrators [to] declare their intent to make an understanding of the impact of violence and victimization an integral part of the mission of their agencies” (p. 6). It would be difficult to argue that methods of improving the understanding of people’s lives and the events that shape them is not a good thing, but, like the use of ACE-testing, the push for trauma-informed services has frequently become overly reductive as it has spread beyond the mental health context. Ultimately, the over-popularization of the ACE study, ACE scoring, and trauma-informed paradigms, especially through social media during the recent years of the pandemic, make us aware of the tension always at play when discerning the value and use of large-scale studies and all that trickles down from them. Surely, professionals of all sorts and the citizens they serve benefit alike from being better informed. We must stay vigilant, however, for the increasing and unhelpful ways that distortions and unexamined overuse of these same tools shape and misshape trauma discourse among the general public. Theologies of Trauma The medicalization of distress, a cultural phenomenon, both influences and is influenced by Christian theological anthropology as well as understandings of God and Jesus. Whether we heard it from a grandmother or a seminary professor, many of us have been deeply shaped by the notions of humankind’s fallen, sinful nature and the idea that were it not for human disobedience, human existence would be perfect, immortal, and, most importantly, free of suffering and distress. This theology makes suffering not just unfortunate but a punishment to be avoided at all costs. It is a de facto theology of distress in which we can easily become perpetually caught between what should be and what is. The theological narrative we hear less often is one in which we are created by God as the finite creatures that we are and are celebrated as good, even within all of our limitedness (Farley, 1990; Tillich, 1951). In this view suffering, while not something to be celebrated, is still an experience of the human condition but one that comes to us without an implicit moral failing. This perspective does not mean that we do not also recognize the ways that humans always fail (in our finitude) to perfectly live into the love, expectations, and unlimited possibilities offered to us by a redeeming, loving, and grace-filled God. These are not just abstract philosophical musings. Our understanding of who we are in our naked creatureliness has practical consequences in feet-on-the-ground everyday living and particular consequences in how we shape a theology of trauma. The emphasis on humanity’s fallen nature also contributes to the Christian tradition’s focus on the woundedness and suffering of Christ and his followers. Paul attributed his own woundedness, a “thorn in the flesh,” to God that he might be “made perfect in weakness” (2 Corinthians 12:9). The belief that wounds are a conduit to faith pervaded the life of the early church, particularly when many endured persecution. In much of Christian theology, woundedness not only binds humans with one another in a common experience but connects humans to the suffering Christ and God. Historically, connection with the suffering Christ emboldened Christians to cope with life in a fallen world. For those who have suffered at the hands of others, the notion of living in the woundedness of Christ can draw one closer to God. The notion that suffering and trauma are inherent to the Christian journey is part of many Christians’ embedded theology.3 Regrettably, such theological perspectives are often used to normalize distress and trauma among contemporary Christians. Similar to the way that trauma language can validate our suffering, the enduring of suffering can be used to validate our faithfulness as Christians. Identifying with the suffering Christ in such a manner can be helpful but in the long term can also leave sufferers stalled in victimhood and unable to envision horizons of hope. Life-limiting theological perspectives on suffering have been employed to justify violence, abuse, and oppression. Conversely, the medicalization of distress has contributed to both implicit and explicit encouragement to take pride in the “privilege to suffer as Christians. . [for such] trials and tribulations in connection with the r are honorable and profitable” (Walker, 2020, paras. 2–3). The valorization of trauma is problematic, especially when emphasized over and above God’s transforming power in a manner that leads Christians to seek suffering (Dyer, 2010–2011). “That Jesus suffered and died for others to bring about salvation models behavior that Christians seek to follow,” thus communicating the message that “suffering is redemptive” (Dyer, 2010–2011, p. 181). Rather than focusing on the uniqueness of Jesus’ suffering, some Christians are misguidedly emboldened to “take up their cross and follow” Jesus (Matthew 16:24), sanctifying their own suffering and trauma and, in some cases, colluding with the abusive acts of perpetrators and transgressors. In contrast, exhortations on suffering such as those found in Hebrews were meant to help Christians resist evil, not to condone it (Stevenson-Moessner, 2003). Rather than perpetuating evil via life-limiting theologies, Christians can act with compassion toward the transformation of trauma and suffering (Swinton, 2007). Shifting problematic, embedded theologies of trauma to more deliberative, life-giving theologies is necessary but can be tremendously difficult. Nonetheless, Scripture and the Christian tradition offer profound wisdom for engaging in this task. Reframing Theologies of Trauma Too often trauma and resilience are framed as dichotomous constructs and experiences; resilience is considered the defeat of trauma (i.e., an outcome) when, according to both scriptural and psychological wisdom, resilience is also a process that co-occurs alongside adversity (Werdel & Wicks, 2012). Scriptural examples of this abound, but given the scope of this article we highlight just three. First, consider how Jacob wrestled with the “angel” as recounted in Genesis. Jacob wrestled the angel, physically toiling throughout the night, until the angel departed at daybreak. Jacob received a blow to the hip that wounded him, crippling him for the rest of his life. But, in spite of the scars, Jacob also received a new name, “Israel,” meaning “one who struggles with God.” Amid the trauma of his battle, a metaphorical and literal confrontation with his own growing edges and with God, Jacob was simultaneously wounded and blessed by the struggle. Second, the New Testament portrays Jesus, time and time again, with his “back against the wall” (Thurman, 1949/1996). In Jesus and the Disinherited, Howard Thurman reminds us of the essential fact that Jesus grew up and lived as a dark-skinned Jew under the oppression of empire. Among all the interpretations of Jesus’ life and death, the most important speak “to those who stand, at a moment in human history, with their backs against the wall” (Thurman, 1949/1996, p. 11). God did not take on human form as a Roman elite but as a poor Jew. Jesus lived as an outcast facing injustice daily. But Jesus’ life is ultimately one that demonstrates resilience amid oppression. He exercised power by choosing his response to the distresses of this world. Jesus taught that the alleviation of distress, or the eradication of injustice, would not be enacted by laws but by the ethical practice of love grounded in love of God, other, and self. Finally, although Jesus did not call Christians to seek trauma and suffering, the Scriptures offer numerous examples of Jesus speaking transparently about the simultaneously arduous and blessed nature of discipleship. Consider, for example, the Beatitudes recounted in Matthew. When Jesus stated, “Blessed are those who hunger and thirst for righteousness, for they will be filled” (Matthew 5:6 NRSV), he was not foreshadowing an eschatological, otherworldly blessing. It was not that the hungry will be blessed; they already are. The struggle for right relationship and justice is both inherently distressing and generative. Despite these scriptural examples of co-occurring resilience and adversity, many Christian theologies of trauma focus most closely, if not entirely, on how the suffering associated with PTSD is reflected in the wounds of Jesus at the end of his life as he hung on a cross. This can undoubtedly be a great comfort to victims of PTSD, especially those just recognizing themselves as such, who feel alone, abandoned, and misunderstood. To stay in this place of woundedness, though, risks condemning victims of trauma to a life of victimhood and undermines the power of ongoing resurrection that recognizes moments of growth amid suffering. Identifying solely with Christ’s wounded nature prevents one from becoming a victim-survivor. The cross is only one end of a continuum of suffering and stresses for Jesus and for all those who live under the thumb of oppression. A theology of trauma cannot overlook the ways that Jesus speaks into the lives of all who live on a continuum of traumatic injuries. In the secular context we as a western culture have held to the particular diagnostic truth that PTSD is the ultimate plumb line by which real trauma is determined. It is true that any theology of trauma must acknowledge that not all distress is traumatic; our finitude ensures that struggle is a part of life. A reframed pastoral theology of trauma, however, must recognize that the life spirit of those with their backs against the wall is a spirit that is denied its freedom and dignity and carries a trauma no less wounding than biomedically sanctioned PTSD. From his earliest days as a refugee through his life as a dark-skinned man living under the foot of empire, Jesus’ life reflects the suffering of people the world over who face injustice and oppression as their daily reality. His life and ministry offer a way of knowing about the world and the struggle it brings. A Christian trauma theology must be inclusive of Jesus’ life as a continuum in which persons of color, those living in poverty, and others see and find hope for their own traumatic struggle, even if it is not reflected in the DSM-5-TR diagnostic criteria for PTSD. Psychological Theories of Trauma Let us begin by noting that contemporary psychological wisdom is heavily informed by the DSM, first created by the American Psychiatric Association in the early 1950s to establish a common nomenclature around psychological pathology and distress that located its origins in biological causes. The advantages of a biomedical diagnostic model for the treatment and care of persons with mental disorders, including PTSD, has been substantial but is not without cost. Locating clinical psychology and diagnosis within a medical framework has legitimized mental illness not only for treatment purposes but also for healthcare reimbursement, pharmaceutical intervention (though dependence on pharmaceuticals may also tip over into a harmful trend), and, importantly, as areas of concern in the eyes of the general public. This deductive model, however, also narrows how we conceive of illness and diagnoses, thereby employing a deficit-based approach that eschews other important social influences that shape life experiences, health and unhealth, and the resourcefulness of individuals. It is these aspects that are especially relevant to expanding our understanding of trauma and that we bring into focus in this article. A history of psychological theories of trauma is beyond the scope of this project; however, it is important to note several touchstones along the way to a developed psychology of what today is termed trauma. Trauma, called in more recent decades shell shock, war neurosis, or combat fatigue, has been well recognized over the centuries as a response to the experiences of war and combat (Crocq & Crocq, 2000). The psychiatric treatment of “post-Vietnam syndrome” in Vietnam War veterans arguably served as an entryway into what became the DSM diagnosis of PTSD (Fassin & Rechtman, 2009). The focus then broadened in subsequent years to include the traumatic experiences of children and eventually of women; perhaps most notable in this regard was the seminal work of Judith Herman (1992). Regardless of the era or the population, psychological theories of trauma reflect and are embedded in the sociocultural context. The United States is unique among other countries in its use of the DSM-5-TR as the diagnostic tool for mental health conditions, including PTSD. Although Australia is rapidly also switching to its use, other member states of the World Health Organization adhere to the International Classification of Diseases (ICD) system, now in its eleventh version, for the centralized classification of all diseases, including mental illnesses. Although our purpose here is not to run a full comparison between the two classification systems, it is helpful to consider how the diagnosis of mental health disorders such as PTSD has been framed in this country and globally. Trauma neurosis, the experience of psychological and physical distress stemming from disasters and other experiences, has had a global presence in the treatment of psychiatric conditions for more than a century and in Japan as early as the 1870s (Goto & Wilson, 2003). The tragic event and consequence of the atomic bombings at Hiroshima and Nagasaki in 1945 were unprecedented in every way, including that of understanding the psychological response to catastrophic traumas. Interestingly, it was not until after the training of Japanese mental health professionals by the U.S. Community Crisis Response Team (CCRT) in response to the 1995 earthquake that PTSD became well known and ultimately the primary frame for understanding the effects of traumatic experience in Japan (Goto & Wilson, 2003). Indigenous and traditional ways of understanding distress are generally disregarded within contemporary psychological theories of trauma. The violence and cultural degradation experienced within many indigenous communities, and among marginalized peoples throughout history and the world, has an intergenerational impact (Danieli, 1998; Menakem, 2017; Pinderhughes, 2004). Distress and trauma do not result from cognitive appraisals made by disembodied organisms, nor are they primarily emotional responses. Distress and trauma are passed among people, including from one generation to the next. The DSM-5-TR diagnostic criteria for PTSD do not reflect this indigenous/traditional wisdom. In authoring the DSM-5, the American Psychiatric Association (2013) did attempt to acknowledge how distress and trauma are cultural constructions and, to aid clinicians in considering the impact of culture when diagnosing clients, they added a “Glossary of Cultural Concepts of Distress” in an appendix. The glossary lists nine common cultural syndromes of distress. For example, khyal cap, or a wind attack, “is a syndrome found among Cambodians in the United States and Cambodia” that includes symptoms of “dizziness, palpitations, shortness of breath, and cold extremities, as well as other symptoms of anxiety and autonomic arousal” (Thornton, 2017, p. 55). The belief that wind may arise within the body and blood, thus causing such symptoms, is acknowledged as a culturally distinctive manifestation of distress. However, khyal cap is then linked back to disorders in the main body of the DSM-5, including distinctly Western perceptions of distress such as panic attack and panic disorders. Therefore, while recent editions of the DSM have given a nod to the impact of social and cultural influences, these have been far outpaced by the rise of neuroscience and the search for neurological evidence of mental health pathology. The failure to integrate various social stressors such as racism, persecution of LGBTQ + persons, economic oppression, and other such factors into the diagnostic model means we often dismiss the severity and impact of having to endure these lifelong threats. Contemporary means of conceptualizing trauma, both clinical and popular, also fail to acknowledge the human tendency to focus on the negative. We “display a negativity bias, or the propensity to attend to, learn from, and use negative information far more than positive information” (Vaish et al., 2008, p. 383). Humans’ negativity bias serves adaptive purposes from an evolutionary perspective, but it also means that negative events have greater psychological, and arguably spiritual, impact than positive events. Conceptualizing all stressful events as traumatic is both an outgrowth of, and fuel for, our negativity bias. The pathology-focused clinical diagnostic frame only further reinforces both. Overemphasizing the negative to the point of normalizing trauma disposes us to minimize our ability to cope and supports deficit- rather than strength-based self-assessments. Consider, for example, the way violence and mass shootings have been normalized within U.S. culture. The widespread nature of such events caused the American Psychological Association to publish a cover story in Monitor on Psychology entitled “Stress of Mass Shootings Causing Cascade of Collective Traumas” (Abrams, 2022). Is the United States, as a nation, collectively traumatized by mass shootings? Though they are tragic events to be sure, Lowe and Galea (2015) reviewed 49 studies on the impact of mass shootings on mental health and found that PTSD prevalence was as low as 3% and as high as 91%, raising significant methodological concerns. Perhaps it is our negativity bias that causes us to conflate stress and trauma and fear in ways that diminish our ability to cope with distressing events. The Stress-Trauma Continuum Dulmus and Hilarski (2003) sought to aid researchers and practitioners in accurately defining the terms “stress,” “trauma,” and “crisis” with the goal of improved assessment and intervention. Toward this end they conceptualized the stress-trauma-crisis continuum to explain the uniqueness of and relationship among these constructs, each of which results from the perception of an event, not the event itself. Although crisis is outside the focus of this special issue of Pastoral Psychology, reconceptualizing a pastoral psychology of trauma is founded upon the stress-trauma continuum. To reiterate, we are not suggesting a continuum that reflects progressive phases of stress that ends at its ultimate, and thus most clinically legitimate, form of PTSD. First, it is essential to remember that not all stress is distress. Eustress is a positive stress response that is not only helpful but necessary for optimal performance. Eustress is “a type of stress that results from challenging but attainable and enjoyable or worthwhile tasks (e.g., participating in an athletic event, giving a speech)” (American Psychological Association, n.d.-b). Eustress differs from distress that is a negative stress response and involves “negative affect and physiological reactivity: a type of stress that results from being overwhelmed by demands, losses, or perceived threats. It has a detrimental effect by generating physical and psychological maladaptation and posing serious health risks for individuals” (American Psychological Association, n.d.-a). The same event—for example, giving a major speech—can cause one person eustress and another distress based upon their perception. Like eustress and distress, trauma also results from perception. “The bomb dropped on Hiroshima may be a trauma-producing event, a military victory, or a divine retribution depending on the individual’s. . attribution and perception of the occurrence” (Dulmus & Hilarski, 2003, p. 29). While distress and trauma can produce the same physiological responses (e.g., hypertension, migraines), the acute and long-term neurological impact of trauma is distinct. Because personality and culture influence our perceptions and appraisals of events, and because our spiritual and religious beliefs and practices influence our perceptions, religious leaders and practitioners of spiritually integrated psychotherapy should utilize the stress-trauma continuum in assessing any and every care receiver’s or client’s presentation of distress. Reframing a Spiritual and Pastoral Psychology of Trauma The above exploration of theological and psychological conceptions of trauma evidences why pastoral psychology as a discipline should be invested in reconceptualizing and reframing understandings of trauma. Our strengths-based, reframed understanding of trauma is built upon the following four working principles: Not all distress is trauma, nor should all distress be avoided. PTSD, as defined in the DSM-5-TR, does not encompass all categories of traumatic distress. Stress and trauma can co-occur with growth and resilience, as evidenced in the wisdom of Scripture and tradition. Stress and trauma exist on a continuum, not a hierarchy, and both are deserving of care. Centering and privileging Jesus’ crucifixion as the Christian example of trauma is a disservice to all those whose own experiences along the stress-trauma continuum leaves them longing to see their own life reflected in the life of Jesus. A deliberative Christian theology recognizes that the cross is only one end of a continuum of suffering reflected in the life of Jesus. Further, life for Jesus began on the margins of society, much as it does for many today living under the thumb of oppression. We ought not rush too quickly to resurrection, yet we must honor the resilience many enact in the face of traumatic experience that leads them to find hope, meaning, and even new life in a post-crucifixion world.4 Jesus’ ministry reflects the complex tensions of living in the unpredictable world of empire with hope constantly under threat. God’s grace revealed in Jesus Christ shows us that it is never either/or but always both/and. The wounds of the world are real, and yet a faith built upon the promise of an always faithful God opens the possibility to choose hope even while experiencing our woundedness. Built upon the promises of God, we are always living in the potential for being simultaneously broken and redeemed. Our distress and traumas alike offer the potential for resilience and, at times, posttraumatic growth. This reconceptualized and reframed spiritual and pastoral psychology of trauma is evident in contemporary examples of distress across myriad cultures, as is shown in the other articles in this special issue. Implications for Spiritual and Pastoral Psychology and Caregiving Religious leaders, spiritual caregivers, and clinicians offering spiritually integrated psychotherapy and care can benefit from grounding their perceptions, assessments, and interventions in a reframed pastoral psychology of trauma. This framework invites professionals to: Recognize the broad range of care receivers’ and clients’ need, whether their experience is most aptly termed distress or trauma. Both necessitate intervention and care. Assist care receivers and clients in identifying language that accurately reflects their distress beyond the biases and fixed terminology of trauma culture. Acknowledge that oppression can, but does not always, have a traumatic effect and that we need to create space for naming and experiencing it as such when relevant. Avoid exporting Western, biomedical conceptions of trauma and colonizing them within other cultures and contexts. We would do well to be mindful of this in our everyday discourse, in how we talk about events occurring in other contexts/cultures and also within intercultural relationships. Provide care receivers and clients with space to shift embedded theological understandings of trauma that center distress to the exclusion of hope, as well as understandings that center hope to the exclusion of distress, and help guide them in constructing more deliberative theologies of trauma. The work of reconceptualizing and reframing understandings of trauma is imperative. But, theories and theologies must be practiced and enacted in order to foster resistance and the possibility of transformation. 3 Drawing on the work of Stone and Duke (1996/2013), Carrie Doehring (2014) defined embedded theology as the “beliefs and values instilled throughout childhood, which exert an unconscious influence and surface under stress. Embedded theologies are those pre-critical and often unexamined beliefs and practices that have become a habitual part of one’s worldview and practices” (para. 8). 4 Socially and historically, the trauma of being Black in the United States is unique. Oppressions quite often compound, making it even more challenging to cope, and yet people keep going. People learn to struggle well, and often it is in resisting that people become resilient. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Abrams Z Stress of mass shootings causing cascade of collective traumas Monitor on Psychology 2022 53 6 20 American Psychiatric Association (2013). Diagnostic and statistical manual of mental disorders (5th ed.). American Psychiatric Association (2022). Diagnostic and statistical manual of mental disorders (5th ed., text rev.). 10.1176/appi.books.9780890425787 American Psychological Association. (n.d.-a).Distress. https://dictionary.apa.org/distress American Psychological Association. (n.d.-b).Eustress. https://dictionary.apa.org/eustress American Psychological Association. (n.d.-c).Trauma. https://www.apa.org/topics/trauma Anda RF Porter LE Brown DW Inside the adverse childhood experience score: Strengths, limitations, and misapplications American Journal of Preventive Medicine 2020 59 2 293 295 10.1016/j.amepre.2020.01.009 32222260 Barbour, I. (1990). Religion and science Harper San Francisco. Bennett, J. (2022, February 4). If everything is ‘trauma,’ is anything? The New York Times https://www.nytimes.com/2022/02/04/opinion/caleb-love-bombing-gaslighting-trauma.html Blake, M. (2022). August 8). U.S. children carry a double burden for gun violence and policy gaps.Newsweek. https://www.newsweek.com/us-children-carry-double-burden-gun-violence-policy-gaps-opinion-1730617 Bonanno GA Mancini AD Beyond resilience and PTSD: Mapping the heterogeneity of responses to potential trauma Psychological Trauma: Theory Research Practice and Policy 2012 4 1 74 83 10.1037/a0017829 Bracken, P. (2002). Trauma: Culture, meaning & philosophy Wiley. Bueckert, L. D., & Schipani, D. S. (2006). Interfaith spiritual caregiving: The case for language care. In L. D. Bueckert, & D. S. Schipani (Eds.), Spiritual caregiving in the hospital: Windows to chaplaincy ministry (pp. 245–263). Pandora Press, in association with the Institute of Mennonite Studies. Committee on Trauma and Committee on Shock (1966). Accidental death and disability: The neglected disease of modern society National Academies Press (US). https://www.ncbi.nlm.nih.gov/books/NBK222962/ Crocq MA Crocq L From shell shock and war neurosis to posttraumatic stress disorder: A history of psychotraumatology Dialogues in clinical neuroscience 2000 2 1 47 55 10.31887/DCNS.2000.2.1/macrocq 22033462 Danieli, Y. (Ed.). (1998). International handbook of multigenerational legacies of trauma. Plenum Press. Davis, J. E. (2020). Chemically imbalanced: Everyday suffering, medication, and our troubled quest for self-mastery. University of Chicago Press. Doehring, C. (2014). Spiritual care after violence: Growing from trauma with lived-theology. The Table Biola University Center for Christian Thought. https://cct.biola.edu/spiritual-care-violence-growing-trauma-lived-theology/ Doehring, C. (2015). The challenges of being bilingual: Methods of integrating psychological and religious studies. In E. A. Maynard, & J. L. Snodgrass (Eds.), Understanding pastoral counseling (pp. 87–99). Springer. Dulmus CN Hilarski C When stress constitutes trauma and trauma constitutes crisis: The stress-trauma-crisis continuum Brief Treatment and Crisis Intervention 2003 3 1 27 35 10.1093/brief-treatment/mhg008 Dyer, B. R. (2010–2011). ‘A great conflict full of suffering’: Suffering in the Epistle to the Hebrews in light of feminist concerns. McMaster Journal of Theology and Ministry, 12, 179–198. http://www.mcmaster.ca.proxy-ln.researchport.umd.edu/mjtm/ Farley, E. (1990). Good and evil: Interpreting a human condition. Fortress Press. Fassin, D., & Rechtman, R. (2009). The empire of trauma: An inquiry into the condition of victimhood (R. Gomme, Trans.). Princeton University Press. Frueh BC Elhai JD Grubaugh AL Monnier J Kashdan TB Sauvageot JA Hamner MB Burkett BG Arana GW Documented combat exposure of US veterans seeking treatment for combat-related post-traumatic stress disorder British Journal of Psychiatry 2005 186 6 467 472 10.1192/bjp.186.6.467 Goto T Wilson JP A review of the history of traumatic stress studies in Japan: From traumatic neurosis to PTSD Trauma Violence & Abuse 2003 4 3 195 209 10.1177/1524838003004003001 Greider, K. (2019). Religious location and counseling: Engaging diversity and difference in views of religion. In J. Snodgrass (Ed.), Navigating religious difference in spiritual care and counseling: Essays in honor of Kathleen J. Greider (pp. 11–44). Claremont Press. Harris, M., & Fallot, R. D. (2001). Envisioning a trauma-informed service system: A vital paradigm shift. In M. Harris, & R. D. Fallot (Eds.), Using trauma theory to design service systems (pp. 3–22). Jossey-Bass/Wiley. Herman, J. (1992). Trauma and recovery: The aftermath of violence—from domestic abuse to political terror. Basic Books. Hillstrom, C. (2022, March 1). The hidden epidemic of brain injuries from domestic violence. The New York Times Magazine. https://www.nytimes.com/2022/03/01/magazine/brain-trauma-domestic-violence.html Holton, M. J. (2011). Building the resilient community: Lessons from the lost boys of Sudan. Cascade Books. Hooks (1994). Teaching to transgress: Education as the practice of freedom Routledge. Krupnik, V. (2019). Trauma or adversity? Traumatology, 25(4), 256–261. 10.1037/trm0000169 LA Blade Digital Staff (2022, July 29). Trauma and suicide risk among LGBTQ + youth; New study released. LA Blade https://www.losangelesblade.com/2022/07/29/trauma-and-suicide-risk-among-lgbtq-youth-new-study-released/ Lowe S Galea S The mental health consequences of mass shootings Trauma Violence & Abuse 2015 18 1 62 82 10.1177/1524838015591572 Marsella, A. J., Friedman, M. J., Gerrity, E. T., & Scurfield, R. M. (1996). Ethnocultural aspects of PTSD: Some closing thoughts. In A. J. Marsella, M. J. Friedman, E. T. Gerrity, & R. M. Scurfield (Eds.), Ethnocultural aspects of posttraumatic stress disorder: Issues, research, and clinical applications (pp. 529–538). American Psychological Association. 10.1037/10555-022 McIntosh, R., Ironson, G., & Krause, N. (2021). Keeping hope alive: Racial-ethnic disparities in distress tolerance are mitigated by religious/spiritual hope among Black Americans. Journal of Psychosomatic Research, 144, 10.1016/j.jpsychores.2021.110403. Article 110403. Menakem, R. (2017). My grandmother’s hands: Racialized trauma and the pathway to mending our hearts and bodies. Central Recovery Press. Moore, E. (2022, July 6). The first Gen Z candidates are running for Congress—and running against compromise. All Things Considered. National Public Radio. https://www.npr.org/2022/07/06/1109193929/the-first-gen-z-candidates-are-running-for-congress-and-running-against-compromi Nichter, M. (1981). Idioms of distress: Alternatives in the expression of psychosocial distress—A case study from South India. Culture Medicine and Psychiatry, 5(4), 379–408. 10.1007/BF00054782 Pinderhughes, E. (2004). The multigenerational transmission of loss and trauma: The african-american experience. In F. Walsh, & M. McGoldrick (Eds.), Living beyond loss: Death in the family (2nd ed., pp. 161–181). W. W. Norton & Co. Stone, H. W., & Duke, J. O. (2013). How to think theologically (3rd ed.). Fortress Press. (Originally published 1996). Streeter, K. (2020, May 18). Running while Black: Our readers respond. The New York Times https://www.nytimes.com/2020/05/18/sports/running-while-black-ahmaud-arbery.html Snodgrass, J. L. (2015). Pastoral counseling: A discipline of unity amid diversity. In E. A. Maynard, & J. L. Snodgrass (Eds.), Understanding pastoral counseling (pp. 1–16). Springer. Spoont MR Sayer N Friedemann-Sanchez G Parker LE Murdoch M Chiros C From trauma to PTSD: Beliefs about sensations, symptoms, and mental illness Qualitative Health Research 2009 19 10 1456 1465 10.1177/1049732309348370 19805807 Stevenson-Moessner J The road to perfection: An interpretation of suffering in Hebrews Interpretation 2003 57 280 290 10.1177/002096430005700305 Summerfield D A critique of seven assumptions behind psychological trauma programmes in war-affected areas Social Science and Medicine 1999 48 10 1449 1462 10.1016/s0277-9536(98)00450-x 10369444 Swinton, J. (2007). Raging with compassion: Pastoral responses to the problem of evil. Wm. B. Eerdmans. Thornton, T. (2017). Cross-cultural psychiatry and validity in DSM-5. In R. G. White, S. Jain, D. M. R. Orr, & U. Read (Eds.), The Palgrave handbook of sociocultural perspectives on global mental health (pp. 51–69). Palgrave Macmillan/Springer Nature. Thurman, H. (1996). Jesus and the disinherited Beacon. (Original work published 1949) Tillich, P. (1951). Systematic theology (1 vol.). University of Chicago Press. Townsend, L. (2009). Introduction to pastoral counseling. Abingdon Press. U.S. Department of Health & Human Services (2021). U.S. Surgeon General issues advisory on youth mental health crisis further exposed by COVID-19 pandemic. https://www.hhs.gov/about/news/2021/12/07/us-surgeon-general-issues-advisory-on-youth-mental-health-crisis-further-exposed-by-covid-19-pandemic.html Vaish, A., Grossman, T., & Woodward, A. (2008). Not all emotions are created equal: The negativity bias in social-emotional development. Psychological Bulletin, 134(3), 383–403. 10.1037/0033-2909.134.3.383 van der Kolk BA Roth S Pelcovitz D Sunday S Spinazzola J Disorders of extreme stress: The empirical foundation of a complex adaptation to trauma Journal of Traumatic Stress 2005 18 5 389 399 10.1002/jts.20047 16281237 Walker, J. (2020). Suffering with Christ. Tabletalk, 53. https://tabletalkmagazine.com/article/2020/10/suffering-with-christ/ Werdel, M. B., & Wicks, J. (2012). Primer in posttraumatic growth: An introduction and guide. John Wiley and Sons. White, R. G., Jain, S., Orr, D. M. R., & Read, U. (Eds.). (2017). The Palgrave handbook of sociocultural perspectives on global mental health. Palgrave Macmillan/Springer Nature.
PMC010xxxxxx/PMC10080856.txt	==== Front Ment Health Prev Ment Health Prev Mental Health & Prevention 2212-6570 Published by Elsevier GmbH. S2212-6570(23)00017-X 10.1016/j.mhp.2023.200275 200275 Article Erratum regarding previously published article 7 4 2023 6 2023 7 4 2023 30 200275200275 © 2023 Published by Elsevier GmbH. 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcThe Declaration of Competing Interest statements were not included in the published version of article that appeared in the Volumes 26C, June 2022 of the Mental Health & Prevention. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper mentioned below. Promoting Educator Social Emotional Competence, Well-Being, and Student-Educator Relationships: A Pilot Study (Volume 26C, June 2022)
PMC010xxxxxx/PMC10083204.txt	==== Front Vaccine Vaccine Vaccine 0264-410X 1873-2518 The Author(s). Published by Elsevier Ltd. S0264-410X(23)00396-1 10.1016/j.vaccine.2023.04.013 Article Promises and challenges of mucosal COVID-19 vaccines Rathore Abhay P.S. a St. John Ashley L. abcd⁎ a Department of Pathology, Duke University Medical Center, Durham, North Carolina 27705, USA b Program in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, 169857 Singapore, Singapore c Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore d SingHealth Duke-NUS Global Health Institute, Singapore ⁎ Corresponding author at: Program in Emerging Infectious Diseases, Duke-National University of Singapore Medical School, 8 College Rd., Level 9, 169857 Singapore, Singapore. 10 4 2023 19 6 2023 10 4 2023 41 27 40424049 © 2023 The Author(s) 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Coronavirus disease-2019 (COVID-19) is an ongoing pandemic caused by the newly emerged virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Currently, COVID-19 vaccines are given intramuscularly and they have been shown to evoke systemic immune responses that are highly efficacious towards preventing severe disease and death. However, vaccine-induced immunity wanes within a short time, and booster doses are currently recommended. Furthermore, current vaccine formulations do not adequately restrict virus infection at the mucosal sites, such as in the nasopharyngeal tract and, therefore, have limited capacity to block virus transmission. With these challenges in mind, several mucosal vaccines are currently being developed with the aim of inducing long-lasting protective immune responses at the mucosal sites where SARS-COV-2 infection begins. Past successes in mucosal vaccinations underscore the potential of these developmental stage SARS-CoV-2 vaccines to reduce disease burden, if not eliminate it altogether. Here, we discuss immune responses that are triggered at the mucosal sites and recent advances in our understanding of mucosal responses induced by SARS-CoV-2 infection and current COVID-19 vaccines. We also highlight several mucosal SARS-COV-2 vaccine formulations that are currently being developed or tested for human use and discuss potential challenges to mucosal vaccination. ==== Body pmc1 Mucosal immunity and its functions Mucus membranes cover body cavities, forming the linings of the respiratory, digestive and reproductive organs. At these sites, foreign matter, including pathogens, can be cleared through distinctive physical properties including the presence of ciliated cells and the production of mucus. Apart from their chemical (e.g., soluble mediators, lysozyme, defensins etc.) and mechanical properties (such as mucociliary transport), the mucosae are also rich immunologically, with specialized cell populations and tissue structures that are key for protection against invading pathogens at each unique mucosal site [[1], [2]]. The respiratory mucosal tissues are comprised of the upper respiratory tract (nostrils, nasal cavity and pharynx) and the lower respiratory tract (trachea, bronchi, bronchioles and alveoli) (Fig. 1 ). At these tissue sites a single layered pseudostratified columnar epithelium forms the first line of defense containing cilia on their apical surface, which facilitate movement of mucus, innocuous substances and pathogens out of the airways [3]. The secretory club cells, mucus producing goblet cells and sensory pulmonary neuroendocrine cells are some of the examples of specialized epithelial cells that are present within the airways, which can coordinate a response to injury or infection with the professional immune cells [[3], [4]]. Various innate, antigen presenting and/or phagocytic immune cells including dendritic cells (DCs), macrophages, mast cells, NK cells and neutrophils are present just under the mucosal epithelial surface [5]. These cells are equipped with innate defenses, can provide early protection against an invading pathogen, and can help initiate the development of an adaptive immune response [[5], [6]]. Although they bear many similarities to immune cell subsets at other sites, there are several examples of immune cells that have developed specialized mucosal-specific phenotypes or activation programs. For example, NK cells, which are a major component of innate host defense at mucosal surfaces, display unique properties in the lungs, tonsils and Peyer’s patches, marked by low cytotoxic functionality and increased production of the cytokine IL-22 in humans [[7], [8]]. These cells were shown to promote epithelial cell release of antimicrobial peptides and epithelial survival [8]. Another example, DCs in the gut have been shown to lack significant expression of TLR4 at steady state, likely because of the high concentrations of LPS produced by host commensal bacteria in the gut [9]. Mast cells also have a unique mucosal-specific subset of cells that contain granules and promote pro-inflammatory responses to pathogens and vaccines [6], which are different from connective tissue resident mast cells, defined by their granule contents [10]. Plasma cells localized in the gut also mostly secrete IgA, the most important antibody for protection of mucosal surfaces [11]. These are only some examples of the unique attributes of mucosal immune cells which allow the immune response in the tissue to be site-specific and for the resulting adaptive immune response generated to retain a phenotype optimized for mucosal protection.Fig. 1 A simplified view of immune responses at the respiratory mucosae. During an exposure to natural or vaccine antigens via nasal delivery, (1) antigens can be taken up by DCs that reside in the respiratory mucosae and presented to the specialized B and TH cells located in the MALT, a lymphoid structure unique to each mucosal site. Certain antigens may also activate mast cells, which can then degranulate and release an array of immune mediators with diverse functions. (2) Antigen-specific lymphocytes that are activated in the MALT can traffic to the nearest draining cervical LN for their proliferation and differentiation. These mucosal tissue draining LNs provide a connecting link between peripheral sites and the systemic immune system. (3) Antigen-specific plasmablasts and/or effector T cells, Tc/TRM can then either directly home in to the mucosae or transit through MALT for their effector functions, (4) such as secretion of IgA, and IgM antibodies. IgA is the most abundantly secreted antibody at mucosal sites and has the capacity to neutralize SARS-CoV-2 at the first exposure site where infection initially begins. URT-upper respiratory tract, LRT-lower respiratory tract, MALT-mucosa associated lymphoid tissue, TH-helper T cell, Tc-cytotoxic T cell, TRM-tissue resident memory T cell, LN-lymph node. Some mucosal tissues are supported by distinct structures that facilitate the transition from innate to adaptive immune responses. This includes the highly compartmentalized mucosal associated lymphoid tissues (MALT) in which immune cells, including lymphocytes, accumulate in and/or traffic through [12]. In particular, MALT are uniquely enriched with B cells that differ both phenotypically and functionally from the B cells that are present in lymphoid tissues such as in the spleen or lymph nodes (LNs) [11]. For example, B cells that are activated in the Peyer’s patches or in the respiratory MALT often class-switch to become predominantly IgA-producing plasma cells [11]. These cells express α4β7 integrins and CCR9 or α4β1 and CCR10 to facilitate their preferential homing into the gut or respiratory mucosae, respectively [[13], [14]]. Although having similarities, these MALT tissues are often specific to the organ or mucosal surface that they protect, with the NALT (nasal associated lymphoid tissue, for rodents) or the analogous human structure, the palatine tonsils and adenoids, being the draining site for antigens exposed to the nasal or oral mucosae, while the Peyer’s patches serve this role for the gut [15]. Although these MALT tissues are connected to draining LNs which, themselves, can have tissue-draining specific properties [15], they have a function of being a dedicated site of immune activation more proximal to the mucosal tissue. This may both allow improved efficiency of immune activation, while also imprinting the environment in which activation occurred on the adaptive immune response and subsequent memory response. As highlighted above, a major aspect of the adaptive immune response at the mucosae is the production of secretory immunoglobulin, IgA, although IgM and IgG are also produced after mucosal challenges [16]. While IgA and IgM have an active transport mechanism across epithelial barriers and into the mucus layer, IgG and, to a lesser extent, other subclasses of antibodies can leak across blood vessels and may be found in saliva or other secretions [17]. Circulating IgA is monomeric while secretory IgA (sIgA) is mainly dimeric and mostly produced by plasma cells that are present in the subepithelial space or lamina propria of the mucosal tissue and transported across into the lumen by polymeric Ig receptor expressed on epithelial cells [18]. Although mice have one form of IgA, two types of IgAs exist in humans, IgA1 and IgA2 and their effector functions are different [19]. Structurally, IgA1 has an extended hinge region compared to IgA2, which is attributed to the insertion of a duplicated amino acid sequence stretch in IgA1 [20]. Functionally, IgA2 antibodies are found to be pro-inflammatory in nature, by activating neutrophils and macrophages more strongly compared to IgA1. These differences result from varied glycosylation profiles between IgA1 and IgA2 antibodies [19]. It is believed that the sIgA dimeric state and glycosylation provide protection from the degradation by high levels of proteases that are present in the mucosal fluids [21]. sIgA is important for blocking the pathogens or irritants that may be present within mucosal cavities. Interestingly, in the gut associated lymphoid tissues, including Peyer’s patches and mesenteric LNs, IgA can be formed and secreted in a T cell-independent manner, as shown by the production of IgA in T cell-deficient mouse models [22]. This T cell-independent IgA often binds to commensal bacteria and it can be induced through T cell independent class-switch recombination that is influenced by dietary factors [[23], [24], [25]]. IgA is more broadly cross-reactive compared to other subclasses of antibodies [[26], [27]], meaning it sometimes can bind to antigens that did not specifically trigger its production. In the context of Influenza, this has been shown to result in more cross-reactive antibodies that bind to different antigenically and evolutionarily divergent strains [28], which could be of particular relevance to SARS-CoV-2, which has evolved into multiple sub-variants [29]. sIgA is also found in breast milk, and may play a role in protection against infections in early life. For example, Influenza-specific IgA levels in breast milk were found to be associated with reduced viral respiratory infections in infants [30]. However, although IgA is key in preventing invasion of pathogens at the mucosal surface, selective IgA deficiency is one of the most common primary immune deficiencies in humans. Although individuals are largely asymptomatic, some may be more prone to recurrent infections [31]. This fact that humans are minimally effected by IgA-deficiency emphasizes the importance of other less-studied aspects of mucosal immunity to immune defense in these tissues, beyond the role of IgA. 2 Mucosal immune responses to SARS-CoV-2 Respiratory pathogens such as SARS-CoV-2 invade through the nasal and oral passages by droplets and aerosols, resulting in infection of the upper and lower respiratory tracts [32]. SARS-CoV-2 emerged as a novel coronavirus in 2019, and is a member of the family Coronaviridae with antigenic similarities and phylogenetic relationships with both seasonal coronaviruses and highly pathogenic coronaviruses such as SARS-CoV-1 and Middle East respiratory syndrome (MERS) viruses [[33], [34], [35]]. Upon exposure to mucosal surfaces, SARS-CoV-2 infects multiciliated airway epithelial cells expressing ACE2/TMPRSS2 receptors [[36], [37]]. However, SARS-CoV-2 is not confined to the upper and lower airways, it also has been shown to infect the gut and other tissues upon autopsy [[38], [39], [40]]. Gut infection by SARS-CoV-2 is characterized by the detection of viral antigen in epithelial cells of the intestine and glands, which is consistent with the expression of ACE2 by these cells [[38], [40]]. Viral RNA is shed in the fecal matter for prolonged periods with longer shedding periods reported for children than adults [41], although it remains to be proven whether shed virus is replication competent and infectious, with literature suggesting contradictory results [[42], [43], [44]]. This, nevertheless, supports that the gut mucosa is a site of SARS-CoV-2 antigen exposure. During natural SARS-CoV-2 infection, IgA levels were elevated in mucosal fluids including bronchoalveolar lavage (BAL) and saliva beginning with the onset of symptoms and were more neutralizing than circulating IgG [[45], [46]]. Antibody-producing plasmablasts with mucosal homing characteristics were identified in the circulation [45]. These cells expressed CCR10, a chemokine receptor and marker for lung homing [[45], [47], [48]], and produced antibodies directed against the Spike protein as well as the nucleocapsid protein [45]. It will be important to understand IgA subclasses, IgA1 vs IgA2, and specificities, that are evoked after natural SARS-CoV-2 infection or after vaccinations and their associations with acute COVID-19 disease and its sequelae. 3 Limited mucosal immune responses to first generation COVID-19 vaccines There are multiple approved vaccines against SARS-CoV-2, reviewed elsewhere [[49], [50]], that use varying approaches or platforms, including mRNA vaccines (e.g., BNT162b2/ Pfizer, mRNA-1273/Moderna), viral vector platforms (Oxford/AstraZeneca/AZD1222/ChAdOx1, Janssen vaccine/Ad26.COV2.S), inactivated vaccines (e.g., CoronaVac/Sinovac, Covaxin/Bharat biotech) and subunit vaccines (e.g., Nuvaxovid/Novavax, Covovax/Serum Institute). These are all given intramuscularly in current approved formats [50]. Of these platforms, mRNA vaccines have shown the highest levels of protection, at least in short-term studies evaluating outcomes within months of vaccination [51]. While current COVID-19 vaccines that are given intramuscularly provide excellent protection against severe disease and death, they do not efficiently limit re-infection and transmission. This may be, in part, due to the fact that systemic immunizations evoke weaker immune responses at mucosal sites, such as in the upper respiratory tract. Limited induction of mucosal immunity coupled with lower accessibility of serum IgG to the upper respiratory tract likely leaves one vulnerable for re-infection. Indeed, intramuscular COVID-19 vaccinations, so far, have failed to induce a sustained IgA response in the nasal and oral cavities [[52], [53], [54]]. In a matched case control study, breakthrough infections assessed within 2–4 weeks after the second dose mRNA vaccination were shown to be associated with lower levels of serum IgA (but not IgG) in study participants compared to those who remain uninfected, suggesting IgA responses may be important in preventing breakthrough infections [52]. During natural SARS-CoV-2 infection, nasal IgA was shown to persist for up to 9 months post-infection [54]. However, it is not known if the neutralizing activity of this IgA persisted after acute infection resolution since, for example, Omicron infections occurred in both vaccinated and previously infected individuals who had received first-generation vaccines based on the Spike protein from the ancestral strain of SARS-CoV-2 [[55], [56]]. Moreover, when convalescent individuals were boosted with the ChAdOx1 vaccine, only the serum IgG response was boosted and nasal IgA titers remained largely unchanged [54]. Mucosal IgA responses were boosted by mRNA vaccination primarily in those who had previous infections [57]. Similarly, unlike those who had prior immunity to SARS-CoV-2 obtained through natural infection, SARS-CoV-2 naïve individuals who received mRNA vaccines lacked virus-specific resident T cells in the nasal secretions and BAL [[58], [59]]. It was also shown that mRNA-vaccinated individuals had lower levels of the Spike receptor binding domain (RBD)-specific IgG or neutralizing antibodies in the BAL compared to convalescent individuals [58]. RBD-specific B cells and Spike-specific CD8 and CD4 T cells in the BAL were also higher in convalescent individuals compared to the vaccines [58]. In contrast to the picture at mucosal sites, vaccine-induced responses were more robust in plasma and PBMCs compared to convalescent individuals [58], although the differences in cellularity could be reflective of recent infection clearance from the upper and lower respiratory tract in convalescent individuals. Nevertheless, these studies have highlighted that the nasal IgA response following natural infection is potentially distinct from that of plasma IgA/IgG responses and not boosted upon further immunization using an intramuscular route. Given the limitations of current COVID-19 vaccines, efforts to develop the next generation vaccine platforms and formulations have begun. It is thought that immunization via the nasal route would induce antigen-specific immune responses in the upper respiratory tract including the nose and oral cavity where SARS-CoV-2 infection begins [60] (Fig. 1). This could have the potential not only to limit infection spread from the upper respiratory tract to lower respiratory tract but may also provide sterilizing immunity, which could reduce virus transmission within the population. 4 Mucosal vaccines for SARS-COV-2: Current knowledge and preclinical pipeline Several vaccine strategies are currently being pursued at various stages of preclinical and clinical development with the aim of improving vaccine-induced mucosal immune responses against SARS-CoV-2. Most pre-clinical studies of SARS-CoV-2 mucosal vaccines have been performed in mice or hamsters. These use various strategies, including subunit vaccines and viral vector-based platforms (Fig. 2 ).Fig. 2 Strategies currently being employed for the development of mucosal SARS-CoV-2 vaccines. In one study, inhalable virus-like particles (VLPs) were used to generate mucosal immune responses. These VLPs consist of recombinant RBD conjugated to lung-derived exosomes [61], which is thought to enhance retention of vaccine in both mucus airways and also in the lung parenchyma. In mice, this vaccine induced RBD-specific IgG in the serum and IgA in the nasopharyngeal lavage and BAL fluids, and CD4 and CD8 T cells in the lung with a strong induction of Th1 cytokines [61]. This strategy also protected hamsters from severe pneumonia after virulent SARS-CoV-2 challenge [61]. Furthermore, the particles comprising the vaccine were stable after lyophilization at room temperature for 3 months [61], which is interesting since stability is a key concern for mRNA vaccines. Other vaccines that are protein-based also have the potential advantage of stability. In another strategy, unadjuvanted Spike was given intranasally as a boost, following a prime with an mRNA vaccine (delivered i.m.). This resulted in induction of resident memory B and T cells and IgA in the respiratory mucosa, and also boosted systemic immunity, which protected hamsters from lethal SARS-CoV-2 infection [62]. These vaccines advance the idea that antigen alone can serve as a powerful inducer of mucosal immunity as either a first dose or booster, with successful outcomes in short-term animal studies. Contrasting these unadjuvanted challenges, there are also strategies that aim to develop adjuvanted vaccines for mucosal delivery (Fig. 2). For example, using three different adjuvants, carbomer-based nanoemulsion adjuvant Adjuplex (ADJ) with CpG or TLR4 agonist glucopyranosyl lipid A (GLA), K18-hACE2 mice (i.e. mice that have been engineered to express the human ACE2 receptor for SARS-CoV-2) were vaccinated intranasally against Spike using a prime-boost strategy. This evoked both respiratory tract-resident and systemic CD4 and CD8 memory T cells and protected against virulent homologous and heterologous SARS-CoV-2 challenges [63]. Those data also suggested protective role for T cells, since viral titers were higher in the lungs after antibody depletion of CD4 or CD8 T cells [63]. We also observed the potential of adjuvants to improve mucosal T cell responses after vaccination when we compared the T cell profile of animals vaccinated intranasally with Spike protein with or without the use of the experimental mucosal adjuvant mastoparan-7 (M7), compared to a standard subcutaneous challenge with Alum [64]. Nasal vaccination with M7 induced heightened T central memory (TCM) cells in the draining lymphoid tissues and spleen compared to unadjuvanted antigen or adjuvanted antigen delivered via a peripheral route [64]. TCM cells are characteristic of long-lived and systemic memory immune responses [[65], [66]]. Memory T cells also showed improved lung and brachial lymph node homing after antigen challenge to the lungs following vaccination against RBD adjuvanted with M7 when delivered to the nasal mucosa, compared to peripheral sub-cutaneous injection [64]. Furthermore, this vaccine strategy induced more broadly cross-protective antibodies that showed enhanced neutralization against multiple SARS-CoV-2 variants of concern [64]. These studies suggest that adjuvants could be used to improve mucosal vaccine responses. Although promising in preclinical testing, to-date, few adjuvants have been tested for mucosal delivery in humans, which has been a limitation to mucosal vaccine development [67]. Alternatively to subunit vaccines, viral-vectored and live-attenuated vaccines are also in development for SARS-CoV-2 infection control. An advantage of live-attenuated vaccines or replicating viral vector platforms is that they could possibly provide higher levels of antigen availability [68]. In one strategy, a live-attenuated Newcastle disease virus encoding Spike (rNDV-S) was administered intranasally in mice, which induced high levels of SARS-CoV-2-specific neutralizing antibodies in the serum, higher IgA and IgG2a antibodies in the pleural fluid and increased CD4 and CD8 T cells in the lung [69]. Hamsters immunized with two doses of this vaccine showed protection from lung infection, inflammation, and pathological lesions following SARS-CoV-2 challenge. Importantly, administration of two doses of intranasal rNDV-S vaccine also significantly reduced SARS-CoV-2 shedding in nasal turbinates and lungs of hamsters [69]. Similarly, intranasal administration of single dose vaccine containing parainfluenza virus 5 (PIV5) expressing Spike protected K18-hACE2 mice from lethal challenge and protected against infection and contact-based transmission in ferrets [70]. Lentivirus vectors have also been used and have demonstrated protection against SARS-CoV-2 in either hamster or mouse models [[71], [72]]. In one study, lentivirus encoding a stabilized Spike, in a non-integrating, non-replicative, non-cytopathic lentivirus was given to K18-hACE2 mice which had previously been given a prime and boost using an mRNA vaccine (i.m.). After waiting 4 months for natural waning of immunity, the animals were cross-immunized intranasally with a lentivirus-expressing Spike from the Beta variant. A strong boost of immunity was detected in terms of increased IgG, IgA and activated immune cells and the vaccine was also shown to provide cross-protection against Delta and Omicron VOCs [72]. A systemic prime followed by intranasal boost strategy was also effective when non-human primates (NHPs) were primed with Spike + Alum, followed by a boost using Spike plus an adjuvant cocktail containing CpG, polyIC and IL15, known as C15 nanoparticles [73]. Although, this formulation generated weaker systemic immune responses, it boosted dimeric IgA and IFNα production in the BAL and virus was cleared faster in NHPs boosted with Spike + CP15 upon challenge [73]. It is also suggested that vaccine formulations involving more than one viral antigen could induce a broader immune response. In this regard, one study utilized a trivalent vaccine containing the viral proteins Spike, nucleocapsid and RdRp, engineered in human or chimpanzee adenoviral vectors [74]. When given intranasally in mice, this formulation generated better humoral and cellular immune responses compared to intramuscular immunization and provided protection from challenges using the ancestral strain and VOCs [74]. It has been suggested that when Spike antigens were expressed in a non-replicating adenovirus type 5 vector as vaccines, there were differences in the cross-reactivity against multiple SARS-CoV-2 strains induced by different Spike sequences. Spike from the ancestral strain induced greater cross-reactive antibodies than Spike from Delta or Omicron, although all of these provided in vivo protection in a hamster model [75]. Together, these studies support that viral vector-based platforms could be viable as mucosal vaccines against SARS-CoV-2. Some of these rely on viruses that can replicate in vivo but are attenuated, while others are engineered for safety considerations to be non-replicating, which can affect antigen persistence [76]. These viral vector based approaches have potential benefits, such as not requiring an adjuvant for immune stimulation, as well as drawbacks, including the potential of off-target immune responses to the vector, or pre-existing immunity to the vector possibly limiting their efficacy or developmental potential. These and additional pros and cons of viral vector strategies have been reviewed elsewhere [76] and additional studies are needed comparing strategies such as viral vector-based platforms to sub-unit vaccines, side-by-side. There are numerous mucosal vaccine candidates, or mucosal boost protocols in clinical trials ( Table 1 ) [77], which show varying degrees of success and highlight some of the potential pitfalls that can meet mucosal vaccine development. In fact, several mucosal vaccine candidates showed limited efficacy in clinical trials. For example, recently, ChAdOx1 was evaluated in individuals who had previously been vaccinated intramuscularly with either ChAdOx1 or approved mRNA vaccines. A small cohort of 30 patients were boosted with a single intranasal ChAdOx1 dose, of multiple concentrations [78]. In this study, the intranasal boost failed to induce mucosal antibody responses that were higher than natural SARS-CoV-2 infection and further testing is currently on hold [79]. Although supporting data are not publicly available, Bharat Biotech’s iNCOVACC vaccine, a nasal spray also containing an adenovirus vector expressing Spike protein, was also recently approved for use in India [79].Table 1 Select mucosal SARS-CoV-2 vaccines at advanced stages of clinical development. Mucosal vaccine Type, delivery method Status iNCOVACC (Bharat Biotech) Non replicating viral vector, nasal drops Approved for use in India, (phase 3 trial completed with non-peer reviewed data available as preprint (https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4342771) CoviLiv (Codagenix) Live attenuated, nasal drops Ongoing phase 3 trial as a part of the WHO-sponsored solidarity trial vaccines Razi Vaccine Protein subunit, nasal spray Ongoing phase 3 trial (https://www.irct.ir/trial/58143) Convidecia (CanSino Biologics) Non replicating viral vector, nasal drops Approved for use as emergency use booster in China, clinical data not available VXA-CoV2-1.1-S (Vaxart) Non replicating viral vector, oral pill Ongoing phase 2 trial (https://clinicaltrials.gov/ct2/show/NCT05067933) In contrast to the testing of a nasally-delivered vaccines or boosts, oral vaccines have also been considered for SARS-CoV-2 [80]. In a single site, dose ranging, open labelled clinical trial, an oral SARS-CoV-2 vaccine comprised of a non-replicating adenoviral vector expressing Spike and nucleocapsid genes combined with a TLR3 agonist generated a cross-reactive IgA response in the nasal secretions and saliva [80]. These antibodies persisted for up to a year and neutralized the delta and omicron VOCs [80]. Supported by data that an orally-administered Adv5-nCOV vaccine was effective in boosting immunity in previously-vaccinated study participants, this strategy promoted by CanSino was recently approved for human use in China [[79], [81]]. Together these data provide evidence that nasal vaccines could be a tool to improve mucosal vaccine protection, while also suggesting that the vaccine platform, route of mucosal delivery and antigen could require optimization. Furthermore, these early attempts at mucosal vaccines against SARS-CoV-2 have provided evidence for potential mechanisms of protection or correlates of protection that could be used to monitor human responses in subsequent clinical trials. Other studies are ongoing, for example human testing of chimpanzee adenovirus-vectored vaccine encoding a stabilized Spike protein (ChAd-SARS-CoV-2-S) [[77], [82]] and a live Newcastle disease virus vector expressing a stabilized Spike protein (AVX/COVID-12-HEXAPRO) [[77], [83]], and these will be likely to provide more information regarding the viability of nasal vaccines in humans. 5 Challenges, historical perspective, and future goals SARS-CoV-2 mucosal vaccine development is built on a long history of efforts to improve vaccines at mucosal surfaces. There have been examples of safe and at least partially successful mucosal vaccines, including against polio virus, V. cholera, S. typhi, rotavirus, and influenza virus [84]. We are reminded of the precedent set by the Salk and Sabin Polio vaccines, where it became apparent that the oral vaccine induced superior mucosal responses including IgA, which protects from infection, while the intramuscular vaccine resulted in limited defense against infection of the gut and polio virus replication and transmission, even though they both strongly protected against poliomyelitis. These vaccines demonstrated the principle that mucosal administration can evoke both localized and systemic protective immune responses [85]. It is possible that SARS-CoV-2 vaccines may also eventually support the importance of mucosal immune protection to transmission, as the polio vaccines have. Although there are recent examples of mucosal vaccines against SARS-CoV-2 being given fast-track approval or emergency approval for use in certain countries, Flumist, comprised of live-attenuated influenza, is the only fully approved nasal vaccine for humans with wide-spread use [86]. In spite of examples of highly successful, safe and protective mucosal vaccines, there are also limitations and clinical development risks. First, there is a concern that mucosal surfaces are more prone to tolerogenic responses, by virtue of their constant exposure to commensals and innocuous foreign substances [84]. These tolerogenic immune programs, often site-specific, have the potential to lead to weak induction of pro-inflammatory responses. In the context of vaccines, breaking tolerance can be aided through the use of effective adjuvants. However, as discussed above, there are limited mucosal adjuvants that have a sufficient safety profile for development as human vaccines, and many of the most promising ones require further testing to demonstrate their safety and efficacy in humans. At mucosal surfaces where ciliated cells quickly clear away debris and pathogens in a protective mucous layer, antigen dilution could be an obstacle to vaccine delivery. This may necessitate optimizing the delivery of vaccine, as well as the dose of antigen/adjuvant. Multiple studies have demonstrated that soluble antigens are slowly absorbed and may promote tolerance [[87], [88], [89]]. Therefore, strategies to generate particulate antigens that could be better absorbed are also in development [[90], [91], [92], [93]] and may be applicable for mucosal vaccines. Furthermore, there may be limitations to our ability to provide mucosal protection against SARS-CoV-2, even with an optimal vaccine formation. Even though natural route infection with SARS-CoV-2 apparently induces superior immune protection at mucosal surfaces than intra-muscular vaccination [[52], [53], [54], [58], [59]], it also provides limited protection against re-infection. Indeed, many individuals experience multiple re-infections with SARS-CoV-2 [[94], [95]], some only months after their initial infection [94]. This outcome was observed prior to the emergence of SARS-CoV-2 in the frequent reinfections caused by seasonal coronaviruses [[96], [97]]. We also do not yet know how repeated antigen exposure at mucosal sites would alter long-term protective immunity. In some contexts, such as allergen immunotherapies, repeated exposure to antigens can re-establish tolerance [98]. Therefore, care must be taken when designing strategies for boosting vaccines in general, and mucosal vaccines as well. And finally, we know that mucosal vaccines, like other vaccine and therapeutic strategies, will also be at risk of becoming obsolete in the face of a highly host-adapted and mutating virus, which will require continued monitoring of newly emerging strains and assessments of long-term vaccine efficacy. Strategies that are currently in development towards targeting cross-reactive epitopes capable of neutralizing multiple coronaviruses could be applicable in this context for limiting the mutation of currently circulating strains as well as preventing the emergence of novel coronaviruses in the future. Yet, vaccines hold the promise of not only being able to induce immunity, but also to be engineered for optimal immunity, which can potentially overcome pathogen antagonism of immune responses, or other mechanisms that result in limited or non-protective immune responses during infection. Mucosal vaccines may also have advantages for vaccine compliance, being relatively easier to administer and noninvasive [99]. 6 Conclusions The information still emerging from research on the basic biology of SARS-CoV-2 and also clinical outcomes of infections and vaccinations, likely, will allow us to design second generation vaccines that are superior to natural immunity, either through vaccine design and/or vaccine schedule. Mucosal vaccines show great promise in solving the limitations of first-generation vaccines and providing needle-free alternatives to the vaccine hesitant. Rational vaccine design utilizing adjuvants and or immunomodulators may further improve the lasting efficacy and durability of vaccine-induced immune responses, an issue that afflicts current COVID-19 vaccines. Author contributions The authors contributed equally to all aspects of the article. Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ashley St. John has a patent pending to Duke-NUS Medical School. Data availability No data was used for the research described in the article. Acknowledgements BioRender was used to generate all figures. The authors acknowledge funding from the SingHealth Duke-NUS Global Health Institute (Duke-NUS/SDGHI_RGA(Khoo)/2021/0008). ==== Refs References 1 Boyton R.J. Openshaw P.J. Pulmonary defences to acute respiratory infection Br Med Bull 61 2002 1 12 11997295 2 Holmgren J. Czerkinsky C. Mucosal immunity and vaccines Nat Med 11 2005 S45 S53 15812489 3 Whitsett J.A. Alenghat T. Respiratory epithelial cells orchestrate pulmonary innate immunity Nat Immunol 16 2015 27 35 25521682 4 Zepp J.A. Morrisey E.E. Cellular crosstalk in the development and regeneration of the respiratory system Nat Rev Mol Cell Biol 20 2019 551 566 31217577 5 Iwasaki A. Foxman E.F. Molony R.D. Early local immune defences in the respiratory tract Nat Rev Immunol 17 2017 7 20 27890913 6 Abraham S.N. St John A.L. Mast cell-orchestrated immunity to pathogens Nat Rev Immunol 10 2010 440 452 20498670 7 Marquardt N. Kekalainen E. Chen P. Kvedaraite E. Wilson J.N. Ivarsson M.A. Human lung natural killer cells are predominantly comprised of highly differentiated hypofunctional CD69(-)CD56(dim) cells J Allergy Clin Immunol 139 2017 1321-30 e4 8 Cella M. Fuchs A. Vermi W. Facchetti F. Otero K. Lennerz J.K. A human natural killer cell subset provides an innate source of IL-22 for mucosal immunity Nature 457 2009 722 725 18978771 9 Coombes J.L. Powrie F. Dendritic cells in intestinal immune regulation Nat Rev Immunol 8 2008 435 446 18500229 10 St John A.L. Rathore A.P.S. Ginhoux F. New perspectives on the origins and heterogeneity of mast cells Nat Rev Immunol 23 2023 55 68 35610312 11 Brandtzaeg P. Johansen F.E. Mucosal B cells: phenotypic characteristics, transcriptional regulation, and homing properties Immunol Rev 206 2005 32 63 16048541 12 Croitoru K. Bienenstock J. 12 - Characteristics and Functions of Mucosa-Associated Lymphoid Tissue Ogra P.L. Mestecky J. Lamm M.E. Strober W. McGhee J.R. Bienenstock J. Handbook of Mucosal Immunology 1994 Academic Press Boston 141 149 13 Kato A. Hulse K.E. Tan B.K. Schleimer R.P. B-lymphocyte lineage cells and the respiratory system J Allergy Clin Immunol 131 2013 933 957 quiz 58 23540615 14 Brandtzaeg P. Mucosal immunity: induction, dissemination, and effector functions Scand J Immunol 70 2009 505 515 19906191 15 Kiyono H. Fukuyama S. NALT- versus Peyer's-patch-mediated mucosal immunity Nat Rev Immunol 4 2004 699 710 15343369 16 Kozlowski P.A. Williams S.B. Lynch R.M. Flanigan T.P. Patterson R.R. Cu-Uvin S. Differential induction of mucosal and systemic antibody responses in women after nasal, rectal, or vaginal immunization: influence of the menstrual cycle J Immunol 169 2002 566 574 12077289 17 Brandtzaeg P. Do salivary antibodies reliably reflect both mucosal and systemic immunity? Ann N Y Acad Sci 1098 2007 288 311 17435136 18 Kaetzel C.S. Robinson J.K. Chintalacharuvu K.R. Vaerman J.P. Lamm M.E. The polymeric immunoglobulin receptor (secretory component) mediates transport of immune complexes across epithelial cells: a local defense function for IgA Proc Natl Acad Sci U S A 88 1991 8796 8800 1924341 19 Steffen U. Koeleman C.A. Sokolova M.V. Bang H. Kleyer A. Rech J. IgA subclasses have different effector functions associated with distinct glycosylation profiles Nat Commun 11 2020 120 31913287 20 Furtado P.B. Whitty P.W. Robertson A. Eaton J.T. Almogren A. Kerr M.A. Solution structure determination of monomeric human IgA2 by X-ray and neutron scattering, analytical ultracentrifugation and constrained modelling: a comparison with monomeric human IgA1 J Mol Biol 338 2004 921 941 15111057 21 Brown W.R. Newcomb R.W. Ishizaka K. Proteolytic degradation of exocrine and serum immunoglobulins J Clin Invest 49 1970 1374 1380 4194190 22 Tezuka H. Abe Y. Asano J. Sato T. Liu J. Iwata M. Prominent role for plasmacytoid dendritic cells in mucosal T cell-independent IgA induction Immunity 34 2011 247 257 21333555 23 Isobe J. Maeda S. Obata Y. Iizuka K. Nakamura Y. Fujimura Y. Commensal-bacteria-derived butyrate promotes the T-cell-independent IgA response in the colon Int Immunol 32 2020 243 258 31858119 24 Tan J. Ni D. Taitz J. Pinget G.V. Read M. Senior A. Dietary protein increases T-cell-independent sIgA production through changes in gut microbiota-derived extracellular vesicles Nat Commun 13 2022 4336 35896537 25 Fagarasan S. Kawamoto S. Kanagawa O. Suzuki K. Adaptive immune regulation in the gut: T cell-dependent and T cell-independent IgA synthesis Annu Rev Immunol 28 2010 243 273 20192805 26 Liew F.Y. Russell S.M. Appleyard G. Brand C.M. Beale J. Cross-protection in mice infected with influenza A virus by the respiratory route is correlated with local IgA antibody rather than serum antibody or cytotoxic T cell reactivity Eur J Immunol 14 1984 350 356 6609824 27 Isho B. Florescu A. Wang A.A. Gommerman J.L. Fantastic IgA plasma cells and where to find them Immunol Rev 303 2021 119 137 34046908 28 Asahi-Ozaki Y. Yoshikawa T. Iwakura Y. Suzuki Y. Tamura S. Kurata T. Secretory IgA antibodies provide cross-protection against infection with different strains of influenza B virus J Med Virol 74 2004 328 335 15332283 29 Tracking SARS-CoV-2 variants. http://www.who.int/activities/tracking-SARS-CoV-2-variants; 2023. 30 Schlaudecker E.P. Steinhoff M.C. Omer S.B. McNeal M.M. Roy E. Arifeen S.E. IgA and neutralizing antibodies to influenza a virus in human milk: a randomized trial of antenatal influenza immunization PLoS One 8 2013 e70867 23967126 31 Yel L. Selective IgA deficiency J Clin Immunol 30 2010 10 16 20101521 32 Li Q. Guan X. Wu P. Wang X. Zhou L. Tong Y. Early Transmission Dynamics in Wuhan, China, of Novel Coronavirus-Infected Pneumonia N Engl J Med 382 2020 1199 1207 31995857 33 Coronaviridae Study Group of the International Committee on Taxonomy of V. The species Severe acute respiratory syndrome-related coronavirus: classifying 2019-nCoV and naming it SARS-CoV-2. Nat Microbiol 2020; 5: 536–44. 34 Le Bert N. Tan A.T. Kunasegaran K. Tham C.Y.L. Hafezi M. Chia A. SARS-CoV-2-specific T cell immunity in cases of COVID-19 and SARS, and uninfected controls Nature 584 2020 457 462 32668444 35 Shrock E. Fujimura E. Kula T. Timms R.T. Lee I.H. Leng Y. Viral epitope profiling of COVID-19 patients reveals cross-reactivity and correlates of severity Science 370 2020 36 Ahn J.H. Kim J. Hong S.P. Choi S.Y. Yang M.J. Ju Y.S. Nasal ciliated cells are primary targets for SARS-CoV-2 replication in the early stage of COVID-19 J Clin Invest 131 2021 37 Hou Y.J. Okuda K. Edwards C.E. Martinez D.R. Asakura T. Dinnon K.H. 3rd SARS-CoV-2 Reverse Genetics Reveals a Variable Infection Gradient in the Respiratory Tract Cell 182 2020 429-46 e14 38 Xiao F. Tang M. Zheng X. Liu Y. Li X. Shan H. Evidence for Gastrointestinal Infection of SARS-CoV-2 Gastroenterology 158 2020 1831-3 e3 39 Delorey T.M. Ziegler C.G.K. Heimberg G. Normand R. Yang Y. Segerstolpe A. COVID-19 tissue atlases reveal SARS-CoV-2 pathology and cellular targets Nature 595 2021 107 113 33915569 40 Liu J. Li Y. Liu Q. Yao Q. Wang X. Zhang H. SARS-CoV-2 cell tropism and multiorgan infection Cell Discov 7 2021 17 33758165 41 Li W.T. Zhang Y. Liu M. Liu Y.Q. Ma X. Prolonged viral shedding in feces of children with COVID-19: a systematic review and synthesis of data Eur J Pediatr 181 2022 4011 4017 36114833 42 Joshi M. Mohandas S. Prasad S. Shinde M. Chavan N. Yadav P.D. Lack of evidence of viability and infectivity of SARS-CoV-2 in the fecal specimens of COVID-19 patients Front Public Health 10 2022 1030249 36339137 43 Cerrada-Romero C. Berastegui-Cabrera J. Camacho-Martinez P. Goikoetxea-Aguirre J. Perez-Palacios P. Santibanez S. Excretion and viability of SARS-CoV-2 in feces and its association with the clinical outcome of COVID-19 Sci Rep 12 2022 7397 35513481 44 Xiao F. Sun J. Xu Y. Li F. Huang X. Li H. Infectious SARS-CoV-2 in Feces of Patient with Severe COVID-19 Emerg Infect Dis 26 2020 1920 1922 32421494 45 Sterlin D. Mathian A. Miyara M. Mohr A. Anna F. Claer L. IgA dominates the early neutralizing antibody response to SARS-CoV-2 Sci Transl Med 2021 13 46 Wang Z. Lorenzi J.C.C. Muecksch F. Finkin S. Viant C. Gaebler C. Enhanced SARS-CoV-2 neutralization by dimeric IgA Sci Transl Med 2021 13 47 Kunkel E.J. Kim C.H. Lazarus N.H. Vierra M.A. Soler D. Bowman E.P. CCR10 expression is a common feature of circulating and mucosal epithelial tissue IgA Ab-secreting cells J Clin Invest 111 2003 1001 1010 12671049 48 Mei H.E. Yoshida T. Sime W. Hiepe F. Thiele K. Manz R.A. Blood-borne human plasma cells in steady state are derived from mucosal immune responses Blood 113 2009 2461 2469 18987362 49 Francis A.I. Ghany S. Gilkes T. Umakanthan S. Review of COVID-19 vaccine subtypes, efficacy and geographical distributions Postgrad Med J 98 2022 389 394 50 COVID-19 Vaccines with WHO Emergency Use Listing. https://extranet.who.int/pqweb/vaccines/vaccinescovid-19-vaccine-eul-issued; 2023. 51 Barouch D.H. Covid-19 Vaccines - Immunity, Variants Boosters N Engl J Med 387 2022 1011 1020 36044620 52 Sheikh-Mohamed S. Isho B. Chao G.Y.C. Zuo M. Cohen C. Lustig Y. Systemic and mucosal IgA responses are variably induced in response to SARS-CoV-2 mRNA vaccination and are associated with protection against subsequent infection Mucosal Immunol 15 2022 799 808 35468942 53 Takamatsu Y. Omata K. Shimizu Y. Kinoshita-Iwamoto N. Terada M. Suzuki T. SARS-CoV-2-Neutralizing Humoral IgA Response Occurs Earlier but Is Modest and Diminishes Faster than IgG Response Microbiol Spectr 10 2022 e0271622 36219096 54 Liew F. Talwar S. Cross A. Willett B.J. Scott S. Logan N. SARS-CoV-2-specific nasal IgA wanes 9 months after hospitalisation with COVID-19 and is not induced by subsequent vaccination EBioMedicine 87 2023 104402 55 Tan S.T. Kwan A.T. Rodriguez-Barraquer I. Singer B.J. Park H.J. Lewnard J.A. Infectiousness of SARS-CoV-2 breakthrough infections and reinfections during the Omicron wave Nat Med 2023 56 Marking U. Havervall S. Greilert-Norin N. Christ W. Gordon M. Marking U. Mucosal Spike-Specific Iga Protects Against Sars-Cov-2 Omicron Infection 16TH VACCINE CONGRESS:P147 2022 57 Longet S. Hargreaves A. Healy S. Brown R. Hornsby H.R. Meardon N. mRNA vaccination drives differential mucosal neutralizing antibody profiles in naive and SARS-CoV-2 previously-infected individuals Front Immunol 13 2022 953949 58 Tang J. Zeng C. Cox T.M. Li C. Son Y.M. Cheon I.S. Respiratory mucosal immunity against SARS-CoV-2 after mRNA vaccination Sci Immunol 7 2022 eadd4853 35857583 59 Lim J.M.E. Tan A.T. Le Bert N. Hang S.K. Low J.G.H. Bertoletti A. SARS-CoV-2 breakthrough infection in vaccinees induces virus-specific nasal-resident CD8+ and CD4+ T cells of broad specificity J Exp Med 219 2022 60 Lavelle E.C. Ward R.W. Mucosal vaccines - fortifying the frontiers Nat Rev Immunol 22 2022 236 250 34312520 61 Wang Z. Popowski K.D. Zhu D. de Juan Abad B.L. Wang X. Liu M. Exosomes decorated with a recombinant SARS-CoV-2 receptor-binding domain as an inhalable COVID-19 vaccine Nat Biomed Eng 6 2022 791 805 35788687 62 Mao T. Israelow B. Pena-Hernandez M.A. Suberi A. Zhou L. Luyten S. Unadjuvanted intranasal spike vaccine elicits protective mucosal immunity against sarbecoviruses Science 378 2022 eabo2523 36302057 63 Kingstad-Bakke B. Lee W. Chandrasekar S.S. Gasper D.J. Salas-Quinchucua C. Cleven T. Vaccine-induced systemic and mucosal T cell immunity to SARS-CoV-2 viral variants Proc Natl Acad Sci U S A. 119 2022 e2118312119 64 O’Neill A, Kala MP, Wah TC, Saron WAA, Mantri CK, Rathore APS, et al. Mucosal vaccination for SARS-CoV-2 elicits superior systemic T central memory function and cross-neutralizing antibodies against variants of concern. bioRxiv. 2022:2022.09.09.507250. 65 Graef P. Buchholz V.R. Stemberger C. Flossdorf M. Henkel L. Schiemann M. Serial transfer of single-cell-derived immunocompetence reveals stemness of CD8(+) central memory T cells Immunity 41 2014 116 126 25035956 66 Wu C.Y. Kirman J.R. Rotte M.J. Davey D.F. Perfetto S.P. Rhee E.G. Distinct lineages of T(H)1 cells have differential capacities for memory cell generation in vivo Nat Immunol 3 2002 852 858 12172546 67 Harandi A.M. Medaglini D. Shattock R.J. Working Group convened by E. Vaccine adjuvants: a priority for vaccine research Vaccine 28 2010 2363 2366 20064476 68 Manicassamy S. Pulendran B. Modulation of adaptive immunity with Toll-like receptors Semin Immunol 21 2009 185 193 19502082 69 Park J.G. Oladunni F.S. Rohaim M.A. Whittingham-Dowd J. Tollitt J. Hodges M.D.J. Immunogenicity and protective efficacy of an intranasal live-attenuated vaccine against SARS-CoV-2 iScience 24 2021 102941 34368648 70 An D. Li K. Rowe D.K. Diaz M.C.H. Griffin E.F. Beavis A.C. Protection of K18-hACE2 mice and ferrets against SARS-CoV-2 challenge by a single-dose mucosal immunization with a parainfluenza virus 5-based COVID-19 vaccine Sci Adv 7 2021 71 Ku M.W. Bourgine M. Authie P. Lopez J. Nemirov K. Moncoq F. Intranasal vaccination with a lentiviral vector protects against SARS-CoV-2 in preclinical animal models Cell Host Microbe 29 2021 236-49 e6 72 Vesin B. Lopez J. Noirat A. Authie P. Fert I. Le Chevalier F. An intranasal lentiviral booster reinforces the waning mRNA vaccine-induced SARS-CoV-2 immunity that it targets to lung mucosa Mol Ther 30 2022 2984 2997 35484842 73 Sui Y. Li J. Zhang R. Prabhu S.K. Andersen H. Venzon D. Protection against SARS-CoV-2 infection by a mucosal vaccine in rhesus macaques JCI Insight 6 2021 74 Afkhami S. D'Agostino M.R. Zhang A. Stacey H.D. Marzok A. Kang A. Respiratory mucosal delivery of next-generation COVID-19 vaccine provides robust protection against both ancestral and variant strains of SARS-CoV-2 Cell 185 2022 896-915 e19 75 Braun M, Martinez C, SeanTucker, Dora E, Showalter L. Mucosal Immunization of Hamsters Elicits Cross-Reactive Antibodies and Decreases Viral Shedding Following Breakthrough Sars-Cov-2 Infection. 16TH VACCINE CONGRESS:P159; 2022. 76 Small J.C. Ertl H.C. Viruses - from pathogens to vaccine carriers Curr Opin Virol 1 2011 241 245 22003377 77 Waltz E. How nasal-spray vaccines could change the pandemic. Nature news feature; 2022; https://www.nature.com/articles/d41586-022-02824-3. 78 Madhavan M. Ritchie A.J. Aboagye J. Jenkin D. Provstgaad-Morys S. Tarbet I. Tolerability and immunogenicity of an intranasally-administered adenovirus-vectored COVID-19 vaccine: An open-label partially-randomised ascending dose phase I trial EBioMedicine 85 2022 104298 79 Carvalho T. Intranasal COVID-19 vaccine fails to induce mucosal immunity Nat Med 28 2022 2439 2440 36329319 80 Johnson S, Martinez CI, Jegede CB, Gutierrez S, Cortese M, Martinez CJ, et al. SARS-CoV-2 oral tablet vaccination induces neutralizing mucosal IgA in a phase 1 open label trial. medRxiv. 2022:2022.07.16.22277601. 81 Li J.X. Wu S.P. Guo X.L. Tang R. Huang B.Y. Chen X.Q. Safety and immunogenicity of heterologous boost immunisation with an orally administered aerosolised Ad5-nCoV after two-dose priming with an inactivated SARS-CoV-2 vaccine in Chinese adults: a randomised, open-label, single-centre trial Lancet Respir Med 10 2022 739 748 35605625 82 Hassan A.O. Kafai N.M. Dmitriev I.P. Fox J.M. Smith B.K. Harvey I.B. A Single-Dose Intranasal ChAd Vaccine Protects Upper and Lower Respiratory Tracts against SARS-CoV-2 Cell 183 2020 169-84 e13 83 Lara-Puente J.H. Carreno J.M. Sun W. Suarez-Martinez A. Ramirez-Martinez L. Quezada-Monroy F. Safety and Immunogenicity of a Newcastle Disease Virus Vector-Based SARS-CoV-2 Vaccine Candidate, AVX/COVID-12-HEXAPRO (Patria) Pigs. mBio. 12 2021 e0190821 84 Lycke N. Recent progress in mucosal vaccine development: potential and limitations Nat Rev Immunol 12 2012 592 605 22828912 85 Sheridan B.S. Lefrancois L. Regional and mucosal memory T cells Nat Immunol 12 2011 485 491 21739671 86 Carter N.J. Curran M.P. Live attenuated influenza vaccine (FluMist(R); Fluenz): a review of its use in the prevention of seasonal influenza in children and adults Drugs 71 2011 1591 1622 21861544 87 Limmer A. Ohl J. Kurts C. Ljunggren H.G. Reiss Y. Groettrup M. Efficient presentation of exogenous antigen by liver endothelial cells to CD8+ T cells results in antigen-specific T-cell tolerance Nat Med 6 2000 1348 1354 11100119 88 Thomas H.C. Parrott M.V. The induction of tolerance to a soluble protein antigen by oral administration Immunology 27 1974 631 639 4474140 89 Hartwell B.L. Pickens C.J. Leon M. Northrup L. Christopher M.A. Griffin J.D. Soluble antigen arrays disarm antigen-specific B cells to promote lasting immune tolerance in experimental autoimmune encephalomyelitis J Autoimmun 93 2018 76 88 30007842 90 Bedford J.G. Heinlein M. Garnham A.L. Nguyen T.H.O. Loudovaris T. Ge C. Unresponsiveness to inhaled antigen is governed by conventional dendritic cells and overridden during infection by monocytes Sci Immunol 5 2020 91 St John A.L. Chan C.Y. Staats H.F. Leong K.W. Abraham S.N. Synthetic mast-cell granules as adjuvants to promote and polarize immunity in lymph nodes Nat Mater 11 2012 250 257 22266469 92 Snapper C.M. Distinct Immunologic Properties of Soluble Versus Particulate Antigens Front Immunol 9 2018 598 29619034 93 Bento D. Staats H.F. Borges O. Effect of particulate adjuvant on the anthrax protective antigen dose required for effective nasal vaccination Vaccine 33 2015 3609 3613 26087299 94 Pulliam J.R.C. van Schalkwyk C. Govender N. von Gottberg A. Cohen C. Groome M.J. Increased risk of SARS-CoV-2 reinfection associated with emergence of Omicron in South Africa Science 376 2022 eabn4947 35289632 95 Bowe B. Xie Y. Al-Aly Z. Acute and postacute sequelae associated with SARS-CoV-2 reinfection Nat Med 28 2022 2398 2405 36357676 96 Callow K.A. Parry H.F. Sergeant M. Tyrrell D.A. The time course of the immune response to experimental coronavirus infection of man Epidemiol Infect 105 1990 435 446 2170159 97 Edridge A.W.D. Kaczorowska J. Hoste A.C.R. Bakker M. Klein M. Loens K. Seasonal coronavirus protective immunity is short-lasting Nat Med 26 2020 1691 1693 32929268 98 Akdis C.A. Akdis M. Advances in allergen immunotherapy: aiming for complete tolerance to allergens Sci Transl Med 7 2015 280ps6 99 Levine M.M. Dougan G. Optimism over vaccines administered via mucosal surfaces Lancet 351 1998 1375 1376 9593404
PMC010xxxxxx/PMC10085874.txt	==== Front J Infect J Infect The Journal of Infection 0163-4453 1532-2742 The British Infection Association. Published by Elsevier Ltd. S0163-4453(23)00204-9 10.1016/j.jinf.2023.04.004 Letter to the Editor Impact of COVID-19 on NHS tuberculosis services: Results of a UK-wide survey Morrison Hazel ⁎ Centre for Clinical Vaccinology and Tropical Medicine, Jenner Vaccine Trials, Churchill Hospital, Oxford, UK Perrin Felicity Department of Respiratory Medicine, King’s College Hospital NHS Foundation Trust, Denmark Hill, London, UK Dedicoat Martin Department of Infectious Diseases, University Hospitals Birmingham, Birmingham UK & TB Unit, UKHSA, 61 Colindale Avenue, London, UK Ahmed Rizwan Department of Respiratory Medicine, Royal Bolton Hospital, Farnworth, Bolton, UK Brown James Department of Respiratory Medicine, Royal Free London NHS Foundation Trust, Royal Free Hospital, Pond Road, London, UK Loughenbury Maria British Thoracic Society, 17 Doughty Street, London, UK Paul Suman Department of Respiratory Medicine, Liverpool University Hospitals NHS Foundation Trust, Royal Liverpool University Hospital, Mount Vernon Street, Liverpool, UK Souto Miguel British Thoracic Society, 17 Doughty Street, London, UK Ward Richard Department of Respiratory Medicine, Homerton University Hospital, Homerton Row, London, UK Lipman Marc Faculty of Medical Sciences, University College London, Gower St, London, UK Department of Respiratory Medicine, Royal Free London NHS Foundation Trust, Royal Free Hospital, Pond Road, London, UK ⁎ Corresponding author. 11 4 2023 7 2023 11 4 2023 87 1 5961 6 4 2023 © 2023 The British Infection Association. Published by Elsevier Ltd. All rights reserved. 2023 The British Infection Association Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcDear Editor, Xu et al. report in this journal the detrimental impact of COVID-19 on tuberculosis (TB) notifications in mainland China. They hypothesize that lockdown directives, including restricted access to hospitals, resulted in reduced opportunities for TB diagnosis.1 As in other countries since the start of the COVID-19 pandemic, the UK National Health Service (NHS) has experienced unparalleled demand to manage waves of SARS-CoV-2 infection whilst attempting to maintain other services. Due to their key public health importance, TB services were directed to remain operational throughout.2 As members of the British Thoracic Society TB Specialist Advisory Group (BTS TB SAG—a multidisciplinary group working in TB from across the UK), we conducted an online survey looking at the effects of the first waves of the pandemic on UK TB services. This was sent via email to all identified TB service leads in the UK in autumn of 2021, with 274 distributed. Responses were received from 72 sites, covering all English regions and the devolved nations, representing both high and low TB incidence areas. Eighty-three percent of responding TB services reported being adversely affected by COVID-19, with TB infection management most impacted. Almost two-thirds reported disruption to immediate contact tracing, with over 85% facing disruption to other latent TB (LTBI) activity. Face-to-face activity was also significantly impacted, with 68% describing this as moderately or greatly affected. Staff redeployment was experienced by nearly 70% of services. Laboratory support was the least impacted area ( Fig. 1). Services reporting themselves to be ‘not affected’ tended to be based in areas of the UK with low TB incidence.Fig. 1 Breakdown of activities affected by COVID-19, by percent of UK TB services. Pts = patients. Fig. 1 As of August 2021, 48% of TB services were fully restored to pre-pandemic levels. Thirty-six percent were partially restored with full restoration planned, with 16% partially restored and unlikely to be fully restored. Free text comments highlighted significant ongoing issues with medication supply and staff redeployment plus a backlog of LTBI cases. Thirty-two percent of respondents thought that changes due to COVID-19 had resulted in long-term detrimental effects. Services reported a loss of clinical space during the pandemic with difficulties in regaining or replacing this and a reduction in staffing numbers, in particular nursing staff. Increased workload was a concern, with staff fatigue and risk of burnout highlighted. Delays in both patients presenting to healthcare and subsequent onward referral to TB services were reported. Some changes were noted as potential positive effects. Many planned to continue utilizing telephone consultations and video observed therapy (VOT). Around a quarter planned to continue enhanced pharmacy services, including home delivery of medications. Upskilling of nursing staff (adaptive roles) enabled clinics to run with less frequent physician input ( Fig. 2).Fig. 2 Planned retention of changes resulting from COVID-19 by percent of TB services. VOT = Video Observed Therapy. Other category responses included increased support for patients in the community rather than in secondary care, better use of IT for virtual multidisciplinary team (MDT) meetings and closer working with other services, such as hepatitis screening services and combined infectious disease/respiratory TB clinics. Fig. 2 This survey highlights the substantial and ongoing impact of COVID-19 on UK TB services. The majority of respondents reported significant disruption, with nearly a third anticipating long-term detrimental changes to their local service. Reductions in staffing levels and loss of clinic space were common negative impacts. Treatment of active TB disease was prioritized but preventative activities, including contact tracing and LTBI treatment, were badly affected. The risk of staff burnout when expected to fill TB and COVID-19 related roles or take on the workload of redeployed colleagues was highlighted. Our results align with the 2021 UK Health Security Agency (UKHSA) data on TB control in England, which reported a significant reduction in LTBI treatment and also saw a fall in TB case notifications in England in 2020, with 4125 notifications compared to 4725 in the previous year.3 Although TB incidence has been declining in the UK, this abrupt fall is unlikely to reflect a true reduction in TB disease. As Xu et al. highlight, delays in identification of those with TB is concerning. Individually, this may lead to more advanced disease at presentation. On a public health level, delays in initiating treatment may result in increased TB transmission. Both were reported within this survey, emphasizing the crucial importance of maintaining TB services to ensure personal and public health. The recovery of TB services is the first priority of the UKHSA TB Action Plan for 2021–26.4 New ways of working and a greater use of remote consultations and treatment monitoring were reported as positive changes. Many felt that these would be maintained as they enhanced pre-existing practice. The crucial role of TB specialist nurses was highlighted, including the positive impact of upskilling nursing staff to run clinics more independently. Adequate support and funding are needed for this to continue and should be considered when future services are developed and commissioned. There were disparities across the UK in the availability of key TB drugs and formulations during this period, which need to be addressed.5 Questions about disruption to drug supply were not explicitly asked in this survey, but free text responses have made it clear that this was of great concern to many. The maintenance of a reliable TB drug supply is crucial to treatment completion and warrants more attention at a national level. Communications from national health bodies to local TB services across the UK were inconsistent during the pandemic. This survey was circulated through BTS and British Infection Association channels but it is uncertain if all TB services were reached, highlighting potential communication gaps. The BTS maintains a list of TB service leads, which should be regularly updated to ensure that information can be rapidly and consistently disseminated during a crisis. Based on themes identified, we highlight several key findings, which may be used to inform future planning to maintain and strengthen UK TB services. Key survey findings • Functioning TB services are a public health priority and maintaining them should be included in healthcare planning for resilience during emergency situations. • To ensure effective communication between central bodies and local services, a comprehensive list of TB services and their leads needs to be maintained. • The UK Joint Tuberculosis Committee and British Thoracic Society have key roles in providing UK leadership and communication with TB service providers. • Digital infrastructure that enables remote consultations and mechanisms which ensure a consistent supply of drugs to patients can mitigate disruption of face-to-face services. • TB services have a capable and resilient workforce who can respond to unforeseen challenges. It is important to ensure that the value of this important NHS asset continues to be recognized. Overall, these results document the considerable disruption experienced even by services directed to continue during the pandemic. Strategies to maintain TB services must be included in healthcare planning for resilience during future emergency situations, and the momentum to achieve this must not be lost. CRediT authorship contribution statement JB, MD, HM, FP and MLi wrote the article. MD, MLi, HM, SP, FP RW and MLo designed and created the survey. MS, MD, FP and MLi collated the data and performed initial analysis. All authors critically reviewed and approved the final report. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Declaration of Competing Interest None. Acknowledgments The authors would like to acknowledge Ms Christina Moll, 10.13039/501100000574 British Thoracic Society , for support provided in conducting the survey. ==== Refs References 1 Xu J. Wang Y. Liu F. Yang H. Changes of tuberculosis infection in mainland China before and after the COVID-19 pandemic J Infect 86 2 2023 154 225 10.1016/j.jinf.2022.12.008 [Epub 2022/12/15. PubMed PMID: 36516903; PMCID: PMC9741555] 2 NHS England and NHS Improvement. COVID-19: provision of tuberculosis services update 2020. Available from: 〈https://www.brit-thoracic.org.uk/covid-19/covid-19-information-for-the-respiratory-community/〉. 3 UK Health Security Agency Tuberculosis in England: 2021 2021 UK Health Security Agency London 4 UK Health Security Agency. TB action plan for England, 2021–2026. London; 2021. 5 DHSC. Department of Health and Social Care medicine supply notification. 〈https://www.sps.nhs.uk/home/planning/medicines-supply-tool/〉, [cited 2022 14 August 2022].
PMC010xxxxxx/PMC10088739.txt	==== Front Curr Nutr Rep Curr Nutr Rep Current Nutrition Reports 2161-3311 Springer US New York 37032416 468 10.1007/s13668-023-00468-x Review Nutritional Quality and Biological Application of Mushroom Protein as a Novel Protein Alternative Ayimbila Francis 12 http://orcid.org/0000-0002-6836-4578 Keawsompong Suttipun [email protected] 12 1 grid.9723.f 0000 0001 0944 049X Specialized Research Units: Prebiotics and Probiotics for Health, Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Bangkok, 10900 Thailand 2 grid.9723.f 0000 0001 0944 049X Center for Advanced Studies for Agriculture and Food, KU Institute of Advanced Studies, Kasetsart University (CASAF, NRU-KU), Bangkok, 10900 Thailand 10 4 2023 2023 12 2 290307 13 3 2023 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Purpose of Review Global concerns about population growth, economic, and nutritional transitions and health have led to the search for a low-cost protein alternative to animal origins. This review provides an overview of the viability of exploring mushroom protein as a future protein alternative considering the nutritional value, quality, digestibility, and biological benefits. Recent Findings Plant proteins are commonly used as alternatives to animal proteins, but the majority of them are low in quality due to a lack of one or more essential amino acids. Edible mushroom proteins usually have a complete essential amino acid profile, meet dietary requirements, and provide economic advantages over animal and plant sources. Mushroom proteins may provide health advantages by eliciting antioxidant, antitumor, angiotensin-converting enzyme (ACE), inhibitory and antimicrobial properties over animal proteins. Protein concentrates, hydrolysates, and peptides from mushrooms are being used to improve human health. Also, edible mushrooms can be used to fortify traditional food to increase protein value and functional qualities. These characteristics highlight mushroom proteins as inexpensive, high-quality proteins that can be used as a meat alternative, as pharmaceuticals, and as treatments to alleviate malnutrition. Summary Edible mushroom proteins are high in quality, low in cost, widely available, and meet environmental and social requirements, making them suitable as sustainable alternative proteins. Keywords Edible mushrooms Alternative protein Protein quality Bioactive proteins issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction Protein has long been regarded as an essential component of the health of man. In addition to being a source of energy, protein serves a variety of vital activities in biological tissues, hormones, or enzymes [1]. Human sources of proteins are mostly derived from animal products such as red and processed meat. Animal proteins are generally considered complete proteins because they contain all nine essential amino acids, but their production is incredibly expensive [2]. In addition, livestock occupies around one-third of all land on the earth. Meat production also contributes significant greenhouse gas emissions (about 14% of all human-caused greenhouse gas emissions), which has a significant environmental impact. Moreover, red and processed meat has been linked to a variety of human health problems, including heart disease and colon cancer [3]. In resolving these problems, plant-based proteins have gained popularity as an alternative to animal proteins in recent decades. This is due to the low cost of production, abundant supply, and presence of bioactive and phytochemical compounds in plant-based proteins [4•]. However, plant proteins are deficient in one or more essential amino acids; thus, plant-based proteins cannot be considered complete proteins [4•]. For instance, cereals contain low values of lysine, and legumes are deficient in sulfur amino acids (e.g., methionine and cysteine) [4•]. Recently, edible mushrooms are being recognized as safe sources of high-quality proteins owing to low fat, high fiber, and functional ingredients such as phenolics (Fig. 1). Mushrooms contain a high amount of protein content with an average value of 23.80 g/100 g dry weight (DW). Mushroom proteins have lately gained acceptance in the food industry in view of their high nutritional value and complete essential amino acids [5–7]. When compared to animal and plant sources, mushroom proteins normally have a complete essential amino acid profile, meeting dietary requirements while having certain economic advantages. Several mushrooms can also grow in agro-industrial waste and produce high yields in a short time. Furthermore, mushroom proteins have a high branched-chain amino acid (BCAA) content, which is mostly found only in animal-based protein sources [8••]. Again, mushroom proteins have high thermal and pH stability and their digestibility of ranges from 60 to 70% [9]. However, the phenolics, phytates, and tannins found in mushrooms have been shown to inhibit digestive enzymes; amylase, pepsin, and pancreatin, while the high fiber content of mushrooms may cause some reducing sugars to be released during digestion, resulting in a Maillard reaction and a decrease in assimilable lysine, methionine, and tryptophan. The lipids that remain may also oxidize, leading to rancidity [10]. Fortunately, protein digestibility can be improved by removing the above-mentioned food components through processing [9]. It is worth noting that mushroom fruiting bodies are commonly consumed as a source of protein, which may provide a substantial portion of amino acids for body functioning as well as fermentable substrates to stimulate the microbiota for host health benefits [11], indicating the ability of both processed and unprocessed mushroom proteins to positively influence human health. Current studies have discovered that mushroom protein concentrates, hydrolysates, and peptides have potent angiotensin-converting enzyme (ACE) inhibitory, antioxidant, antimicrobial, anticancer, antiviral, and gut microbiota modulation properties [8••, 11]. Moreover, there are other bioactive proteins found in mushrooms include lectins, fungal immunomodulatory proteins (FIP), ribosome-inactivating proteins (RIP), antimicrobial/antifungal proteins, ribonucleases, and laccases [12]. Notably, these point to mushrooms as a viable source of bioactive proteins alternative to animal sources. However, because there are thousands of different kinds of mushrooms, the best mushroom species in terms of high protein quantity and quality are sought after by food industries for effective utilization.Fig. 1 Mushrooms as safe sources of quality proteins and functional ingredients [108] Increased production of high-quantity and quality protein is required to meet the growing demand resulting from global population growth, economic and nutritional transitions, and health concerns [13]. It has been predicted that by 2050, the global population will be surpassed 9 billion, implying a rise in food consumption. According to the Food and Agriculture Organization (FAO), agricultural production will have to expand by 70% to fulfill demand [14]. Subsequently, global protein demand will rise, and in the absence of alternative sources, environmental resources will be under intense pressure. As a result, an alternative protein source, such as edible mushrooms, that can provide high-quality protein at a low cost, faster, and with little to no negative environmental impact, would be much preferred. This review aims to reveal the feasibility of using mushroom protein as an alternative protein to conventional protein sources, taking into account important factors such as protein quality, digestibility, and biological benefits. Because there is little available literature on the use of mushroom protein for future protein sources, this review may be especially useful in uncovering the importance of using this underutilized source of protein to combat malnutrition, as a meat substitute, and as a pharmaceutical compound. Methods To find relevant articles, we searched Google Scholar, PubMed, and Scopus using the terms “edible mushroom” OR “edible mushroom protein” with the filters “protein quality,” “protein digestibility,” and “biological functions” alone or in any combination. Several articles that were pertinent to the main subject were used, with the majority of them being those that were released in English between 2020 and 2022. Only very relevant earlier articles were added. Research on inedible mushrooms was not included. Nutritional Value of Edible Mushroom Proteins Mushrooms must be available as a high-protein sources before they can be considered an acceptable alternative protein source. In 2018 alone, about 9 million tons of cultivated mushrooms were produced worldwide according to data from the United Nations’ Food and Agriculture Organization [15]. The most common farmed species are Agaricus bisporus (white button mushroom), Lentinula edodes (shiitake), Pleurotus ostreatus (oyster mushroom), and Flammulina Velutipes (golden needle mushroom). Agaricus bisporus is the most extensively consumed fungus in the world, followed by Pleurotus spp. and Lentinus edodes [9]. Several other edible mushrooms with high protein values are also cultivated worldwide. The human body requires a significant amount of protein for growth and maintenance as regards physiological functions, such as the vital performance of hormones and enzymes [8••]. Though the protein value of mushrooms varies depending on species and strains, maturation stage, the substrate used for cultivation, and other environmental factors, mushrooms provide significant protein at a lower cost than plant and animal sources [16]. Protein value is requisite since protein accounts for around 17% of total calorie consumption [13]. Many reports unveiled that crude protein is particularly found in high levels in mushrooms. Protein content in edible mushrooms ranged from 6.60 to 36.87 g/100 with an average value of 23.80 g/100 g dry weight [17] as shown in Table 1. Tricholoma exhibited the highest value of protein, while Laetiporus sulphureus and Polyporus dictyopus showed the lowest content [5]. Popular edible mushroom species such as Lentinus edodes, Agaricus spp., and Pleurotus spp. contained 14.87 to 27.13% [18], 26.60 to 39.84% [6], and 18 to 19.15 g/100 of protein [19], respectively. Crude protein ranged from 6.60 to 30.69 g/100 g among mushrooms obtained from the Kilum-Ijim forest in Cameroon [7]. Lentinus squarrosulus powder presented an excellent protein value of 30.12 g/100 g [11]. Even though the whole fruiting body of a mushroom is commonly consumed, it is interesting to note that different parts of the mushroom present different protein values. Nutritional analysis of growing mushrooms in South Africa revealed protein values ranging between 18% (L. deliciosus) to 37.0% (B. edulis), with the pileus having richer protein [20]. Lentinus crinitus comprised a protein value of 14.4% (pileus) and 9.5% (stipe) [21]. The data show that edible mushrooms have high protein levels, but this varies by species and morphology (pileus or stipe). Despite these influences, some edible mushrooms are noted to have a higher protein value than vegetables, fruits, and grains [5].Table 1 Nutritional values of some edible mushrooms Mushroom Protein, g/100 g Reference Tricholoma 36.87 [5] Copyinds comatus (MUII. Fr) Gray 30.90 Volvariella volvacea (Bull.: Fr.) Sing. 28.10 Russula vinosa Lindblad 27.26 Agaricus blazei Murrill 26.60 Morchella esculenta 25.85 Cordyceps militaris 25.56 Agrocybe aegerita 24.79 Boletus 23.99 Lentinus edodes (Berk.) Sing 23.26 Pleurotus eryngii 19.15 Dictyophora indusiate (Vent.ex Pers) 18.25 Polyporus tenuiculus 10.89 [7] Termitomyces striatus 21.76 Termitomyces macrocarpus 30.69 Auricularia polytricha 17.44 Laetiporus sulphureus 8.62 Termitomyces sp.1 28.24 Termitomyces sp.2 21.26 Polyporus dictyopus 6.60 Boletus edulis Pileus (37.0%), stipe (21.3%) [20] Boletus mirabilis Pileus (33.0%), stipe (27.4%) Lactarius deliciosus Pileus (20.8%), stipe (18.0%) P. ostreatus 18.08% [19] A. bisporus 29.64 to 39.84% [6] L. edodes 14.80 to 27.13% [18] L. squarrosulus 30.12 g/100 g [11] The nutritional value of mushroom protein is determined not only by its quantity but also by its ability to meet dietary requirements; recommended dietary allowance (RDA) and protein efficiency ratio (PER). Based on the data presented in Table 1 (reports within 2020–2022), species of Tricholoma, Copyinds, Volvariella, Termitomyces, Lentinus, and Agaricus exhibited high protein value (25–40%). Notably, 100 g of mushrooms can provide between 29.41 and 66.0% of the RDA for men and between 35.80 and 80.35% of the RDA for women, whereas beef jerky and whole milk can provide between 47.0 and 59.28% for men and between 57.22 and 67.75% for women [8••]. According to USDA data [22] and a review report [8••], P. ostreatus (black oyster) showed the highest protein efficiency ratio (PER) of any mushroom, surpassing beef jerky. A. bisporus (Portobello) and A. brasilensis also outperformed jerky in terms of PER. A. bisporus (Champignon) had a PER comparable to lentils, Pleurotus djamor, Pleurotus eryngii, and Pleurotus ostreatus (white oyster) displayed PER similar to black beans, and Flammulina velutipes and L. edodes had the lowest PER of the mushrooms, equivalent to whole milk. It is important to point out that a lack of information in the literature limits the realization of RDA and PER of other high-protein mushrooms. Meanwhile, the information presented indicates that mushroom species such as Agaricus and Pleurotus appear to have good protein value and PER. The protein value of animal sources (on a dry basis) is 27% for milk, 53% for eggs, 37–83% for meat, and 58–90% for fish and crustaceans. Proteins are found in legumes at 22–40%, cereals at 8–18%, nuts at 4–20%, other seeds at 18–32%, and tubers at less than 10% [13]. Some edible mushrooms can provide protein values that are higher than or comparable to animal sources such as milk, egg, meat, and fish, as well as the highest plant-based protein sources. Thus, edible mushrooms are an excellent source of high-quality protein that can be produced more easily, more cheaply, and with less impact on the environment [8••]. Edible mushrooms as a protein source offer an appealing alternative to animal and other plant protein sources. Quality of Mushroom Protein Mushroom proteins have attracted more attention in recent times beside the lower production costs and environmental issues over animal and other plant proteins and pose some unique qualities that make them suitable alternative protein sources in the future. The ability to provide essential amino acids for growth and bodily functions is the essence of mushroom quality [23]. Several protein-containing food scoring systems have been developed to effectively compare the quality of protein foods. Extensive review reports on strategies for scoring protein-containing foods have lately been published [8••, 13]; hence, this section will focus on some commonly used methods. The Essential Amino Acid Score (EAAS), also known as the chemical score, compares the proportion of each essential amino acid in a test protein to a reference standard that contains all of the essential amino acids in the appropriate quantities to meet the demands, according to the WHO/FAO/UNU reference [8••, 24]. On the report of González et al., A. bisporus, P. djamor, P. ostreatus, and Lentinus edodes recorded EAA scores > 1.0, which met EAA requirements, whereas Agaricus brasilensis, Pleurotus eryngii, Pleurotus ostreatus, and Flammulina velutipes had EAA scores less than 1.0 due to limiting in some individual amino acids such as isoleucine and valine, leucine, leucine, and leucine, respectively. Even though these values vary greatly among mushrooms, they indicate that mushrooms can provide a high amount of quality protein, particularly Agaricus spp., Pleurotus spp. and Letinus edodes. Moreover, Pleurotus citrinopileatus, Pleurotus geesteranus, Pleurotus eryngii, Oudemansiella raphanipes, Pholiota adiposa, and Hericium erinaceus were shown to have a complete range of amino acids and Amino Acid Scores comparable to the WHO standard [25]. Lentinula edodes strains, particularly the strain named Shenxiang 18, exhibited good amino acid profile and protein quality [26]. The quality of the amino acid profile is determined by the combination of free and bound amino acids (AA). Hericium erinaceus, P. cystidiosus, P. eryngi, and P. sajor-caju had the highest levels of essential free and bound AAs and chemical scores for isoleucine, tryptophan, and phenylalanine. The free proportion of used mushrooms had isoleucine (Ile) levels equivalent to or more than the best five plant sources, whereas tryptophan (Trp) levels were nearly double [27]. Leucine, valine, and glutamic acid were the three most prevalent essential amino acids (EAA) in P. colossus. Other EAA included lysine, phenylalanine, histidine, tryptophan, and methionine [28]. In another study, six amino acids, aspartic acid, glycine, alanine, proline, histidine, and arginine, were found in Cordyceps militaris fruiting bodies [29]. The levels of amino acids, for example, varied among Agaricus bisporus from the same source, indicating the influence of production conditions. Cooking also resulted in 50% losses of glutamic acid, arginine, glycine, serine, threonine, proline, and alanine. During canning, however, glutamic acid, serine, valine, proline, arginine, glycine, and aspartic acid losses were higher (70%) [30]. A study investigated free amino acid profile changes in raw, sautéed, and roasted portobello and shiitake, and certain volatiles from mushroom culinary preparation. Cooking methods caused a significant free amino acid loss, while mushroom variety significantly impacted most amino acid contents [31]. L. edodes grown on logs had lower levels of amino acids than sawdust [32]. L. edodes fruiting body extracts revealed the presence of 36 essential primary metabolites, including amino acids, organic acids, and sugars. A study looked into the effects of different packaging on the umami taste and aroma of dried Suillus granulatus. The content of l-Aspartic acid was significantly lower than that of l-Glutamic acid. During storage, the changes in l-Glutamic acid and total Monosodium glutamate (MSG)-like amino acids were consistent. After 2, 4, and 6 months of storage, the total content of MSG-like amino acids in light-proof packaging (LPP) was higher than that in light-transparent packaging (LTP), but lower than that in LTP at 8 and 10 months [33]. Indicating that a variety of factors interact to determine the amino acid concentration during storage. Free amino acids play a very important role in the presentation of the taste and deliciousness of edible mushrooms. A recent study found that the value of EAA/ (EAA + NEAA) among the five types of edible fungus studied ranged from 32.20 to 41.87%, and the value of EAA/NEAA was 47.48 to 72.03%. EAA/ (EAA + NEAA) and EAA/NEAA values were lowest in Lentinus edodes but Pleurotus citrinopileatus best fulfilled the optimal protein standard [18]. In all, the above data point to the fact that mushroom proteins have a complete essential amino acid profile, though the amount varied by variety of factors such as species, production, and processing conditions, but cannot be generalized. This rather determine whether a particular mushroom can offer high-quality protein as best substitute protein. Protein digestibility is useful for estimating protein nutritional quality. The amount of protein accessible for absorption after digestion is determined by how easily peptide linkages are hydrolyzed. Protein Digestibility Corrected Amino Acid Score (PDCAAS) is one of the earliest methods the Food and Agriculture Organization and the World Health Organization devised to evaluate protein quality. Protein digestibility-correlate amino acid score (PDCAAS) assesses protein quality by taking into account both human amino acid needs and digestive capabilities. PDCAAS values for several edible mushroom species and other plant and animal-origin foods have been reported. PDCAAS values for mushrooms ranged from 0.35 to 0.70 based on in vitro and in vivo digestibility studies. Scores for Agaricus brasiliensis, Lentinus edodes, Pleurotus ostreatus, Agaricus macrosporus, and Tricholoma terreum were 0.36, 0.38, 0.44, 0.40, and 0.70, respectively. Compared to other protein sources some mushrooms outperformed oilseeds; 0.48, fruits; 0.64 and cereals; 0.58 and comparable to tubers; 0.73 and vegetables; 0.74, but lower than meat and dairy with a score of 0.94. It should also be highlighted that using mushrooms two times the weight of meat and dairy could result in a score equivalent to or higher than these animal proteins. Moreover, the Biological Value (BV) of protein is the percentage of amino acids ingested by the intestines that the body retains. The amount of nitrogen consumed and excreted is used for the calculation. First, the required nitrogen losses in the urine and feces must be estimated, which necessitates giving nitrogen-free diets [8••]. The BV score of mushrooms (80) is at par with milk (100) and meat (80–85), and higher than cereal (40–45) and legume (50–55) [34]. The excellent digestion justifies the use of mushroom protein as an alternative protein in the future. Mushroom protein digestion has been studied both in vitro and in vivo. The digestibility of mushroom protein can be altered by a variety of factors, including anti-nutritional factors (phenolics, phytates and tannins, trypsin inhibitors and hemagglutinins). This content, however, is below the WHO toxicity level and poses no risk to humans [8••]. Few works have reported the digestibility of processed and unprocessed mushroom proteins, particularly in the last 3 years. Protein concentrate was produced from Pleurotus ostreatus [9]. When Pleurotus mushrooms with 18.3% protein were digested in vitro with trypsin, the digestibility was 68.2% [35]. INFOGEST in vitro digestion (which simulates oral, gastric, and intestinal conditions) revealed that the concentrate digested greatly than mushroom flour. After gastric digestion, the hydrolysis degree (HD) of the mushroom flour and the protein concentrate were 16.5% and 20.3%, respectively. The HD of the protein concentrate increased the most when it transitioned from the gastric to the intestinal phase, rising to an HD of 76.2 ± 1.3%, whereas mushroom flour only reached an HD of 23.5 ± 4.6%. Several proteolytic enzymes are secreted during intestinal digestion, and it is most likely that these enzymes in the pancreatin completely digest the proteins from the concentrate into smaller peptides. It was also found that [36], cooking and canning reduced the number of amino acids present, but in vitro, gastric and intestinal digestion increased the overall amino acid concentration and allowed the detection of two new amino acids (arginine and methionine). The majority of the amino acids were released during the intestinal phase of in vitro digestion. Mushrooms provide enough amino acids per gram of protein that meet the majority of FAO amino acid patterns for adults after in vitro digestion. Overall, mushroom protein digestibility is excellent, supporting PDAAS and BV ratings. This makes edible mushrooms an important part of human nutrition. The Biological Role of Mushroom Proteins in Human Diet Conventionally, mushrooms have been consumed as a source of protein as part of a meal and as an ingredient in food preparations. In both ways, the digestibility of the mushroom protein fraction is vital in terms of impacting host physiology and health. High digestion of protein is paramount in releasing amino acids to support host physiology. Concurrently, unhydrolyzed protein may improve health by stimulating the gut microbiota as revealed in previous studies. Ayimbila et al. found that simulated gastro-intestinal digestion of L. squarrosulus powder resulted in 58.59% of its protein hydrolyzed in gastric condition and only reached 59.59% after hydrolysis in intestinal condition [11]. Protein profile and digestibility of G. lingzhi (GZ) and G. lucidum (GL)-Madrid mushroom proteins in simulated gastric fluid differ significantly. GL and GZ contain some proteins that are totally or partially resistant to simulated gastric fluid [37]. Partially hydrolyzed protein components in the mushroom are fermentable by gut microbes to release branch-chain fatty acids to enhance host health [11]. Dietary fiber in the aforementioned mushrooms may have reduced protein digestibility by obstructing enzymatic diffusion and limiting protein hydrolysis. This renders mushrooms suitable for consumption as part of a regular diet in typical food matrixes [38]. Edible mushrooms have recently been used for food fortification or enrichment. According to the Codex General Principles for the Addition of Essential Nutrients to Foods, “fortification” is defined as the addition of one or more essential nutrients to a food product, whether or not that nutrient is typically present in the food. Fortification helps to prevent, reduce, and control micronutrient deficiencies [8••]. Incorporating mushrooms into food products boosts nutritional value, particularly protein, as evidenced by the following studies. The addition of L. edodes (5–15%) and A. auricula (15%) increased the protein content of sorghum biscuits. However, the protein content of T. fuciformis inclusion was comparable to that of control biscuits. Proteins in biscuits had major bands with molecular weights ranging from 18 to 28 kDa before hydrolysis. After in vitro digestion, L. edodes and T. fuciformis enrichment increased the soluble protein content (small peptide) of sorghum biscuits. The protein profile of 15% T. fuciformis contained a small band at 12 kDa, indicating an increase in the small Mw protein fractions after in vitro digestion [39]. By adding 5% A. bisporus flour to beef patties, the protein content increased significantly, along with an increase in dietary fiber and a decrease in fat and sodium [40]. Also, cakes fortified with 10% to 15% Agaricus bisporus powder increased protein and were found to be the most satisfying [41]. According to a study, adding 15% shiitake powder increased the protein content of noodles. Noodles (15.64 ± 0.12%) with shiitake cap powder had a higher protein content than noodles (14.44 ± 0.02%) with stem powder and noodles (15.23 ± 0.06%) with whole shiitake powder compared to the control (13.35 ± 0.06%) [42]. Kolawole et al. indicated that with the addition of 30% sclerotium flour to Orange Fleshed Sweet Potato (OFSP) and sclerotium of Pleurotus tubberegium blended cookies (OFSP) flour, the protein and fiber contents of the cookies increased by approximately 95% while ash content increased by 62% [43]. Pleurotus ostreatus mushroom enriched noodles (MFN) had greater protein, fiber, iron, calcium, and potassium content. Mushroom powder supplements of 5%, 8%, and 10% increased the protein content (g/100 g) to 14.40, 14.72, and 16.58, respectively, as opposed to the 12.75 in noodles made solely of wheat flour [44]. Indeed, the inclusion of mushrooms in food products increase the protein value as well as the dietary fiber required to improve health. Furthermore, food that is nutritious, delicious, and high in protein from plants and mushrooms is becoming more popular. These meat substitutes satisfy dietary requirements and enhance personal well-being. In addition to providing dietary protein, lipids and fatty acids, vitamins, fiber, and flavor, mushrooms can enhance the organoleptic or sensory qualities of processed foods, such as meat substitutes. Mushrooms are fibrous, which makes the meat analogues that are made from them more chewable. Fusarium graminearu was the first edible filamentous fungus to be used in sausages and burger patties. The sweetness and umami flavor of fungi gives food a taste that is similar to meat and improves palatability [45]. Mushrooms in meat analogues-based products provide nutrients and promote the appearance, texture, and flavor of the product. To create an extruded mushroom-based meat substitute with a 35% water content, 15% each of Lentinus edodes (LE), Pleurotus ostreatus (PO), and Coprinus comatus (CC) and soybean protein isolate were used. The textural profiles of the CC derived meat were strikingly similar to those of real beef [46]. The products from the LE and CC mushrooms, however, had hardness values that were most similar to those of beef. Regardless of this, springiness of meat analogues and various mushroom species was comparable. Thus, the addition of various mushroom species has a significant impact on the texture of the meat analogues. Also, the textural qualities and antioxidant activity of the full fat soy (FFS)-based meat analog were improved by the addition of oyster mushrooms [47]. The addition of soy proteins creates a fibrous-structured of meat analog in which the oyster mushroom content reduced the expansion ratio and enhanced water absorption indices [48]. Therefore, mushrooms are an important ingredient in muscle foods because of the fibrous structure, which resembles that of meat and imparts a distinct umami flavor. Therapeutic Properties of Edible Mushroom Proteins Mushroom bioactive components are also appealing to consumers and food scientists because they can improve health and reduce the risk disease. Specifically, after the SARS-CoV-2 (COVID-19) pandemic era, people are becoming more interested in using food to improve health (41). In terms of human health, red and processed meats have been linked to cardiovascular disease and colon cancer. This is because some animal-derived foods contain high levels of cholesterol and saturated fat, both of which are harmful to the heart. Concerning colon cancer, it is thought to be caused by protein fermentation in the distal colon, releasing toxic metabolites such as ammonia, amines, phenols, and sulfides [8••]. Long-term high protein diets increase the risk of type 2 diabetes (T2DM), obesity, central nervous system (CNS) diseases, and cardiovascular disease (CVD) by increasing the production of amines, H2S, and ammonia in the colon [27]. Contrary, mushroom proteins have been linked with medicinal properties, and specific protein preparations or isolates such as concentrates, hydrolysates, peptides, ageritins, lectins, fungal immunomodulatory proteins (FIP), ribosome-inactivating proteins (RIP), antimicrobial/antifungal proteins, ribonucleases, and laccases [12] have been studied. They exert a variety of health benefits such as improved digestion, absorption of exogenic nutritional constituents, immune function modification to help the host defend against pathogen invasions, and suppression of specific enzyme activity [49]. This occurs as a result of the ability to induce angiotensin-converting enzyme (ACE) inhibitory, antioxidant, antimicrobial, and anticancer properties (Fig. 2). In Table 2, the biological function of these protein fractions from edible mushrooms is shown. The production of protein concentrates from mushrooms may result in enhanced digestibility since many of the components that impede digestion may have been eliminated. Few studies have been reported on the health effects of mushroom protein concentrates recently. A Boletus edulis anti-tumor protein (BEAP) with a MW of 16.7 KD displayed strong anti-cancer activity on A549 (human non-small-cell lung cancer) cells both in vitro and in vivo. BEAP cytotoxicity was aided by the activation of apoptosis and the arrest of A549 cells in the G1 phase of the cell cycle [50]. Likewise, the protein extract, PS60 from P. tuber-regium sclerotium was the most effective protein extract against the breast cancer cell line MDA-MB-23. In MDA-MB-231 cells, PS60 elicited cytotoxic effects that resulted in apoptosis and cell cycle arrest at the G1/G0 and S phases [51]. Yet, Pholiota nameko protein (PNAP) displayed anti-proliferative and apoptosis-inducing effects in a human breast cancer cell line (MCF-7). The malignant proliferation of MCF-7 solid tumors can be successfully stopped by PNAP, according to in vivo tests. This is because PNAP can effectively activate the mitochondrial apoptosis and death receptor pathways of MCF-7 tumor cells in vivo, causing the cancer cells to wither [52]. Protein extracts from Auricularia auricula-judae were effective as ciprofloxacin and fluconazole in inhibiting Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, yeast (Candida albicans), and dermatophytic pathogens [53]. Protein extracts from two different mushroom species (oyster and button) demonstrated significant antimicrobial activity against P. aeruginosa and B. subtilis [54]. Hence, it would be interesting to exploit mushroom protein concentrates to control various diseases and live a healthy life.Fig. 2 Importance of mushroom proteins as bioactive compounds [78•] Table 2 Health benefits of some mushroom proteins in human diet and as therapeutic agents Protein isolates Health benefits Source Features Reference Peptides ACE inhibitory Lentinula edodes 1265.43 Da N-terminal: KIGSRSRFDVT [66] S. rugosoannulata Peptide mixtures [67] Agaricus bisporus Peptide mixtures [68] Ganoderma sinense Peptide mixtures [109] Grifola frondose (mycelia) Peptide mixtures [69] Antioxidant Schizophyllum commune MW < 0.65 kDa [74] Hericium erinaceus MW 0.65 kDa [75] Agrocybe aegerita Peptide mixtures [76] Antioxidant and ACE inhibitory Boletus mushroom KBMPHF1 (> 10 kDa), KBMPHF2 (3–10 kDa), KBMPHF3 (1–3 kDa), and KBMPHF4 (1 kDa) [80] Antioxidant Agaricus bisporus Peptides, 1–3 kDa fraction [77] Antioxidant activity, ACE inhibitory activity, and anticancer activity King Boletus mushroom Peptide mixtures [81] Morchella importuna 831 Da Ser-Leu-Ser-Leu-Ser-Val-Ala-Arg [52] Hepatoprotective and gut microbiota modulation Pleurotus citrinopileatus Peptide mixtures [84] Neuroprotection and gut microbiota modulation Se-enriched Cordyceps militaris VPRKL(Se)M (Se-P1) and RYNA(Se)MNDYT (Se-P2) [85] Antiviral (coronaviruses) Pseudoplectania nigrella, Russula paludosa, and Clitocybe sinopica Peptide mixtures [82] Anti-inflammation Tricholoma matsutake Peptide mixtures N-terminal: SDLKHFPF and SDIKHFPF [86] Ribonuclease Anti-HIV viral Lepista personata Ribonuclease 27.8 kDa [90] Ribotoxin-like proteins C. aegerita ribotoxin-like proteins (enzymes) 15 kDa [110] Ostreatin Novel tool for biotechnological applications Pleurotus ostreatus ribotoxin-like proteins: 131 amino acid and 14,263.51 Da Extract Antitumor Pleurotus tuber-regium Protein extract [51] Pholiota nameko Protein extract [52] Boletus edulis Protein extract 16.7 KD [50] Antimicrobial Auricularia auricula-judae Aqueous protein extracts [53] Mushroom (Oyster and button) Protein extracts [54] Inonotus hispidus Mixtures of peptides, proteins and other compounds [111] Protein hydrolysates Neuroprotective effects Pleurotus geesteranus Hydrolysates [58] Antioxidative, angiotensin rennin converting enzyme (ACE) inhibitory and antiproliferative activities Pleurotus ostreatus Hydrolysates [57] Hepatoprotective effects Pleurotus ostreatus Hydrolysates [112] Antioxidant properties and cytoprotective effects Pleurotus geesteranus Hydrolysates [59] Antioxidants and reduction of lipid peroxidation Ganoderma lucidum Hydrolysates [60] Protein hydrolysates contain a mixture of polypeptides, oligopeptides, and free amino acids that can be produced by chemical (using acids or alkalis) or enzymatic (using proteases) methods [55]. By simulating gastrointestinal digestion, protein hydrolysates with neuroprotection made from Pleurotus geesteranus proteins showed a good pre-protective impact in oxidatively damaged PC12 cells. The hydrolysate pre-protection may also change the expression of endogenous antioxidant enzymes [56]. Protein hydrolysates with varying degrees of hydrolysis were found to have an antioxidative, ACE inhibitory, and antiproliferative properties [57]. P. geesteranus protein hydrolysates show neuroprotective activity in H2O2-damaged pheochromocytoma (PC12) cells by reducing ROS production and increasing antioxidant enzymatic system activity [58]. Also, protein hydrolysates (MTT) derived from Pleurotus ostreatus exhibited profound antioxidative and ACE inhibitory activities. Besides, remarkable antiproliferative properties of MPHs against the human cervical carcinoma cell line (HeLa) were shown [57]. In other reports, Pleurotus ostreatus protein hydrolysate (POPEP-III) induced strengthened serum ALT and AST activities, and oxidative liver histological alteration in mice. It was reported Pleurotus geesteranus hydrolysates (PGPH) induced superior antioxidant and cytoprotective effects [59], while Lingzhi protein hydrolysates displayed good antioxidant activity and reduced lipid peroxidation [60]. Protein hydrolysates with hydrolysis degree ≥ 10% are usually intended for the development of specialized food products. Athletes make extensive use of food products containing protein hydrolysates [8••]. Protein hydrolysates are known to be more easily and quickly absorbed than native proteins, and when combined with carbohydrates, they produce an insulinotropic effect, proving useful for increasing muscle glycogen and muscle mass. This aids digestion and is useful in the production of products for patients with impaired gastrointestinal function [61]. Also, protein hydrolysates are suitable for the development of hypoallergenic foods due to a reduced or eliminated antigenic potential. Although the bitter taste that is produced when some hydrophobic peptides are released during hydrolysis limits the use of protein hydrolysates in the food industry, the bitterness can be masked with other flavors, removed through enzymatic and chromatographic methods, or processed using activated charcoal [62]. As a result, edible mushrooms are a safe source of bioactive protein hydrolysates. Therapeutic Role of Bioactive Proteins from Edible Mushrooms Recent findings on the biological function of proteins are shown in Table 2. Bioactive peptides (BAPs) are small fragments of proteins that provide some physiological health benefits [63]. Edible mushrooms are interesting sources of bioactive peptides because they contain a considerable quantity of high-quality proteins. The biological function of most bioactive proteins has been attributed to the encoded BAPs that can be released without losing their bioactivities [64]. Current reports showed that mushroom peptides render antihypertensive, antioxidant, antimicrobial, and other functions [17]. Angiotensin-Converting Enzyme (ACE) Inhibitory Property Hypertension is a chronic health problem that causes patients to have high blood pressure leading to heart disease, stroke, aneurysm, and renal failure. Fortunately, ACE inhibitors including peptides are available to treat hypertension [65]. ACE inhibitory peptides with different molecular weights (MW) and amino acids composition from mushrooms have been reported lately. A synthesized peptide from Lentinula edodes, named KIGSRSRFDVT with MW of 1265.43 Da, induced ACE inhibitory activity (IC50) of 37.14 μM. KIGSRSRFDVT is a non-competitive inhibitor that binds at an inactive ACE site to inhibit ACE activity [66]. It was shown that Stropharia rugosoannulata peptides can bind to zinc ions, critical amino acids, or amino acid residues in the ACE active pocket, which inhibits the action of ACE [67]. Hydrolysis of A. bisporus scraps yielded three novel ACE inhibitory peptides; LVYP, VYPW, and YPWT which exhibited an average ACE inhibitory activity of 80.68%, and the IC50 value was 0.9 mg/mL. They also showed good tolerance to temperature, pH, and gastrointestinal digestive enzymes, indicating excellent properties for the development of drugs for lowering blood pressure [68]. Peptides from Grifola frondosa mycelia hydrolysate induced higher ACE inhibitory activity [69]. When compared to chemosynthetic medications, mushroom peptides may have fewer negative effects on humans and have the ability to decrease blood pressure. However, clinical studies are needed to endorse these claims. Antioxidant Effects In the process of normal cellular metabolism, free radicals and reactive species, such as reactive oxygen species (ROS), are created continuously in the human body. Endogenous enzymatic and nonenzymatic defense systems quickly remove free radicals and reactive species; however, under certain conditions, such as drug use, inflammation, air pollution, smoking, and irradiation, endogenous antioxidant systems can be overwhelmed, resulting in oxidative stress, which can cause aging, cancer, and atherosclerosis [70, 71]. Although numerous studies have revealed that hydrolyzed peptides and proteins reduce enzymatic and nonenzymatic oxidation by eliminating free radicals and chelating metal ions, the exact mechanism by which mushroom peptides exert antioxidant properties is still not entirely understood. Peptides may act as antioxidants to eliminate free radicals directly by supplying protons and/or electrons, or indirectly by suppressing endogenous oxidases (e.g., via activation of the Keap1-Nrf2 signaling pathway), and chelating metal ions implicated in a radical generation [17, 72, 73]. Antioxidant peptides contain 5–16 amino acids. Studies have confirmed excellent antioxidant peptides (0.65–3 kDa) from Schizophyllum commune [74], Hericium erinaceus [75], Agrocybe aegerita [76], and A. bisporus [77]. Peptide composition, structure, and hydrophobicity are primarily responsible for their antioxidant capabilities [78•]. Antitumor Property Active ingredients with antitumor effects have been isolated from mushrooms. A new peptide (MIPP) from Morchella importuna lowered human cervical cancer HeLa cell line viability. MIPP inhibited cell proliferation via a mitochondrial-dependent mechanism, as evidenced by Bcl-2/Bax downregulation, facilitation of cytochrome C transport from the mitochondria to the cytoplasm, and activation of caspase-9 and caspase-3 [79]. Four novel bioactive peptides > 10 kDa obtained from Boletus mushroom displayed antioxidant and ACE inhibitory activity greatly by KBMPHF4 fraction [80]. Again, King Boletus mushroom protein hydrolysate or bioactive peptide (eb-KBM) isolated by enzymatic method demonstrated high antioxidant activity, ACE inhibitory activity, and anticancer activity-relevant cytotoxicity in ChaGo-K1 (undifferentiated lung carcinoma) and HEP-G2 (hepatocarcinoma) cells. It was concluded that eb-KBM elicits a high biological activity due to the high content of hydrophobic and aromatic amino acids [81]. Other Bioactivities Several studies have revealed that mushroom protein has the potential to be used control pathogenic microbes and other human diseases. Peptides derived from Pseudoplectania nigrella, Russula paludosa, and Clitocybe sinopica exhibited binding affinity and the ability to modulate the flexibility and stability of selected coronavirus proteins, including ACE-related carboxypeptidase, SARS-Coronavirus HR2 Domain, and COVID-19 main protease [82]. Nowadays, the hepatoprotective effects of polysaccharide-peptides from mushrooms have been evaluated against nonalcoholic fatty liver disease (NAFLD). It is known that nutrient digestion and absorption are mediated by the hepatointestinal system. Dysbiosis in the gut and modifications to its metabolic processes are linked to NAFLD [83]. Pleurotus citrinopileatus polysaccharide-peptides (PSI and PSII) were shown by Huang et al. [84] to exhibit hepatoprotective effects in injured HepG2 cells by increasing the survival rates of injured cells, decreasing the accumulation of intracellular TGs, increasing the intracellular activity of SOD, reducing extracellular transaminase release, and maintaining cell integrity. PSI and PSII boosted both the richness and diversity of the human gut microbiota. Escherichia-Shigella genera were less prevalent due to PSI and PSII, while SCFAs were improved, which impacted liver functioning. Therefore, PSI and PSII may induce effects via the liver-gut axis system. Similarly, two novel selenium peptides (Se-Ps), VPRKL(Se)M (Se-P1) and RYNA(Se)MNDYT (Se-P2), isolated from Se-enriched Cordyceps militaris induced pre-protection against LPS-induced inflammatory and oxidative stress in the colon and brain by inhibiting the production of proinflammatory mediators. Se-Ps improved intestinal mucosa and positively affected gut microbiota dysbacteriosis [85]. Also, Tricholoma matsutake-derived peptides (SDLKHFPF and SDIKHFPF) attenuated ethanol-induced inflammatory responses and apoptosis by suppressing NF-κB signaling activation [86]. The peptides SDIKHFPF and SDLKHFPF produced from the Tricholoma matsutake improved barrier function by controlling TJ protein expression and the release of pro-inflammatory cytokines [87] as shown in Fig. 3.Fig. 3 Molecular mechanism through which Tricholoma matsutake-derived peptides SDIKHFPF (left) and SDLKHFPF (right) suppress the NF-κB/MLCK/p-MLC signaling pathway in DSS-induced colitis mice [113] Ageritin is a particular ribonuclease that is isolated from the edible fungus Cyclocybe aegerita (also known as Agrocybe aegerita). It cleaves a single phosphodiester bond present within the universally conserved alpha-sarcin loop (SRL) of 23-28S rRNAs. Apoptosis, which is the process by which cells die, occurs after this cleavage inhibits protein production. Ageritin exhibits ribonucleolytic activity on ribosomes, ribonuclease activity on Tobacco Mosaic Virus (TMV) RNA, endonuclease activity on a plasmid and genomic DNAs, and antiproliferative and defense activities, which have been fully reviewed in recent review paper [88]. Ageritin has considerable beneficial impacts on the viability of cancer SVT2 cells, but only slightly on healthy BALB/c 3T3 cells, according to a study on the selective toxicity of the toxin against malignant cells [89]. In addition, ageritin induces antifungal, entomotoxic, and nematotoxic, antibacterial activities [88]. Additionally, the Lepista personata ribonuclease suppressed HIV-1 reverse transcriptase [90]. Discovering new medications to stop the worldwide pandemic infection using natural bioactive molecules could be a promising avenue. Ways to Exploit Mushroom Protein in the Future Edible mushrooms and their proteins have the potential to be extensively involved in a variety of areas with diverse applications in the future. Feeding the growing world population, mitigating and adapting to climate change, reducing pollution, waste and biodiversity loss, and preserving human health are just a few of the many issues that the modern food and agriculture sector must address quickly. Food should also be tasty, affordable, convenient, and safe [91]. By 2050, 9.2 billion people are expected to live on earth and consume twice as many resources as today. FAO estimates that agricultural production will need to increase by 70% to feed the entire population [92]. Based on nutritional value, quality, and digestibility, as well as the associated health benefits and economic advantages, mushrooms can be used as source of protein in a variety of ways (Fig. 4).Fig. 4 Different ways to exploit mushroom proteins [114] Mushrooms Provide Future Alternative Protein to Fight Food Insecurity and Malnutrition Asia and Africa are coping with serious challenges with hunger and malnutrition, based on the Global Hunger Index report in 2020. Also, due to the COVID-19 epidemic, the ensuing economic collapse, and a significant desert locust outbreak in the Horn of Africa, millions of people are experiencing food and nutrition insecurity [93]. The increase in COVID-19 also had an indirect effect on human health. Moreover, because of the significant increase in poverty and food insecurity recently, people are compelled to switch to less healthy and low-quality diets. As a result, the risks of undernutrition, especially protein deficits, have increased, affecting both high- and low-income countries [91, 93]. By 2030, governments around the world must achieve food security, reduce hunger, and improve nutrition, especially for the underprivileged and most vulnerable populations, including infants. Nearly 690 million people or 8.9% of the world’s population are estimated to be undernourished, mostly in Asia (381 million), Africa (250 million), Latin America, and the Caribbean (48 million) (WHO 2020). The ever-increasing human requirement for protein-rich food and the inefficiency of conventional technologies have necessitated the need to carefully investigate options for creating affordable and novel protein-rich foods, with related health benefits. Using mushrooms in a form of eating the whole fruiting body (fresh or powder), protein concentrates, and hydrolysates offers nutrition and medicinal advantages [23]. In addition, the immunomodulatory agents released during digestion could stimulate intestinal immunity to fight diseases. Undigested mushroom carbohydrates and proteins constitute the major substrates at the disposal of the microbiota, which have been shown to stimulate the microbiota by promoting the growth of beneficial microbes and SCFA production [11, 94]. Mushrooms clearly provide bioactive substances that can aid in disease control and improvement in malnourished populations. Additionally, mushroom protein, agentin have useful applications in agriculture. Given the increasing worldwide food demand caused by population growth, novel management measures for crop protection against pathogens or pests must be tested, while minimizing the use of ecologically damaging phytochemicals [88]. Given that the ageritin protein product has insecticidal activity, transfecting the ageritin gene into plant cells could be a potential strategy for controlling diseases or pests. This is feasible in light of recent developments in in vitro cultures and genetic plant engineering. Given Ageritin’s antifungal action, a similar experimental strategy is helpful for preventing fungal illnesses. Because ‘Ageritin’ toxin is present in Pioppino edible mushroom, which is commonly consumed, the use of Ageritin for plant protection against diseases can be easily accepted by the public [89]. Overall, the broad framework supports additional research on Ageritin and homologous members of the RL-Ps group for controlling pathogens in crops in order to increase food production. Mushroom Protein is an Excellent Substitute for People Who Do Not Consume Animal Protein The nutritional demands of individuals who do not eat animal products are met by meat substitutes [95]. Religious convictions and animal compassion are the main motivations for consuming such non-animal products, beside nutritional and health benefits and environmental considerations [8••]. A vegetarian or vegan diet is gaining popularity. According to research and market alternatives, there are two generations of products based on traditional proteins such as soy or gluten, as well as newer generation proteins such as peas or faba beans [96]. Edible mushrooms offer a cheap and less resource-intensive source of protein to partially replace meat or meat products [97]. Mushrooms may play a key role in meat analogs by delivering nutrients and stimulating the development of sensory qualities such as the appearance, texture, and flavor [46]. Edible mushrooms have been utilized in meat product as meat replacements or fillers to increase the physicochemical and sensory attributes and nutritional quality. Mycoprotein is a high-protein, low-fat dietary ingredient that is created by manufacturers by fermenting fungal spores with glucose and other ingredients [98, 99]. According to Singh et al., although Fusarium venenatum is grown to produce mycoprotein and make meat substitutes, it is rarely employed to generate meat analogues due to its limited digestibility [100]. Mycoproteins have a biological value comparable to typical meats and are high in quality proteins, dietary fiber (-glucans and chitin), and other nutrients. Mycoproteins are also highly digestible (0.99), equivalent to animal protein sources such as milk, and important amino acids [101]. Consuming mycoprotein is linked to lower glycaemic indicators and energy density consumption [102]. Many Asian countries use Monascus purpureus, which is treated with yeast to produce red rice, and Aspergillus oryzae, which is fermented with soy to make hamanato, miso, and shoyu. The British-developed meat alternative QuornTM is now offered in the European market. The use of P. albidus mycoprotein flour can aggregate nutritional and biological value in chocolate cookies [98]. Therefore, future years will undoubtedly witness an increase in the need for non-animal protein as we search for alternative protein sources to satisfy the demands of the growing population. Mushrooms offer some optimism because of their nutrient hub and simplicity of modification. Notably, products made from mushroom mycoproteins are a promising new generation of functional alternative proteins since they have a meaty flavor, excellent nutrition, and biological properties. Mushroom Proteins are Important Pharmaceutical Agents Another important feature of bioactive proteins is the ability to be used as pharmaceutical agents. Mushroom proteins and peptides have antihypertensive, immunomodulatory, antifungal, antibiotic, and antibacterial activities, and anticancer, antiviral, antioxidant, and ACE inhibitory effects [50, 52, 78•, 86]. Considering the different biological activities in Table 1 (searched articles within 2020–2022) it emerged that about 25% of bioactive proteins possessed ACE inhibitory activity, mainly peptides (single and mixture) and only one protein hydrolysate. Whereas about 30% mostly being peptides and protein hydrolysates exhibited antioxidant activity, while about 25% composed of peptides, hydrolysates, and extracts showed hepatoprotective, antiviral, and anticancer activities, and the others displayed neuroprotection, antimicrobial, gut modulation anti-inflammation properties. These bioactive proteins were obtained from popular mushrooms including A. bisporus, Lentinula edodes, Pleurotus spp, and Ganoderma spp. Others include Schizophyllum commune, Auricularia auricula-judae, Inonotus hispidus, Boletus mushroom, and Tricholoma matsutake, with Pleurotus species emerged as the primary source of bioactive proteins and peptides making up majority of the proteins. Nevertheless, compared to the enormous number of peptides isolated from plants and animals, only a small number of peptides derived from mushrooms are currently recognized. Also, less than 0.5% of the thousands of documented mushroom species are utilized for food and medicine, which include Lentinula edodes, Pleurotus spp., Agaricus spp., and Ganoderma spp. Other edible mushrooms, however, have significant or even high protein content that can be exploited. Lectins are also of therapeutic or pharmaceutical interest. Lectins are non-catalytic proteins that reversibly bind to sugars. Individual lectins typically bind their ligands with a high degree of stereochemical selectivity. The applications of lectins from mushrooms in terms of their antiproliferative activity, immune-stimulating, antimicrobial, and antioxidant effects have been highlighted [103]. A. bisporus lectin (ABL) and A. bisporus mannose-binding protein (Abmb) exhibited anti-proliferative effects on cancer cells as well as an immune system-stimulating property [104]. Yousra et al. review report indicated that mushroom lectins have potent inhibitory activity against a variety of human pathogenic viruses including HIV, herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), hepatitis C virus (HCV), and influenza virus. The lectins work by preventing viral entry and inhibiting replication through enzyme inactivation [105]. Despite that, lectins differ in structure, molecular weight, and carbohydrate specificity, which influences their pharmaceutical applications. Lectins have been discovered in mushroom species such as Hygrophorus, Agaricus, Boletus, Russula, Pleurotus, Agrocybe, Lentinus, Grifola, and Ganoderma. Lectins include fungal immunomodulatory proteins, ubiquitin-like proteins, enzymes, and unclassified proteins that are carbohydrate-free or possess less than 1–2% carbohydrate. The low-carbohydrate proteins and peptides (LCP) exert anticancer activities via specific pathways including DNase activity, endoplasmic reticulum stress, PI3K/Akt/mTOR-signaling pathway, and ubiquitin-mediated pathway, which are different from the common extrinsic or intrinsic apoptosis pathways [106]. Lately, interest in prebiotic property of mushroom fruity bodies (fresh or powder) and extracted compounds such as polysaccharide-peptides is growing. Prebiotics are food compounds that affect the gut microbiota’s composition or metabolism positively, including bifidogenic bacteria (Bifidobacterium sp.) and lactic acid bacteria (Lactobacillus sp.). Prebiotics are involved in pathogenic suppression, gastrointestinal tolerance, and probiotic growth stimulation. Polysaccharides in edible mushrooms, such as hemicellulose, chitin–and–glucans, mannans, xylans, and galactans slow digestion [17, 107]. The hydrolysates can serve as substrates to promote the growth of beneficial gut microbes and their metabolite production leading to health benefits. Short-chain fatty acids (SCFA), primarily acetic, butyric, and propionic acids, are the primary end products of bacterial fermentation of unhydrolyzed carbohydrates and proteins in the gut [11]. Concerns over the effects of gut dysbiosis on diseases like inflammatory bowel disease (IBD), diabetes, cancer, obesity, and liver disease have lately grown. The digestion and absorption of nutrients have an impact on health. Humans have long used mushrooms as food and medicine, and potential applications for mushroom components such as protein are currently being explored. Recent work revealed that polysaccharide-peptides (PSI and PSII) from P. citrinopileatus excite protective effects on hepatoprotective and gut microbiota [84]. The adiponectin pathway was stimulated by PSI and PSII, which also resulted in less lipid buildup in liver cells, modulated gut microbiota, and increased butyric and acetic acids production, suggesting that the liver-gut axis system is a mechanism through which PSI and PSII elicit these beneficial effects. In another report, the simulated digestion of protein extracted from selenium-enriched Cordyceps militaris yielded two selenium peptides, VPRKL(Se)M (Se-P1) and RYNA(Se)MNDYT (Se-P2). Se-Ps promoted biological activities such as lessening inflammation and oxidative stress (OS) in the brain, reducing LPS-Induced inflammation and OS in the colon, and potentially modulating the relative abundance of gut microbiota of LPS-Injured mice. Se-P2 increased the abundance of Lactobacillus and Alistipes but decreased the abundance of Akkermansia and Bacteroides. Thus, Se-Ps collectively affected the gut and gut microbiota, which may offer a crucial strategy to lessen neuroinflammation and associated Alzheimer’s disease via the microbiota-gut-brain axis [85]. Thus, the use of mushrooms as a future alternative protein source may provide bioactive compounds that can stimulate the gut microbiota to control or prevent a variety of human diseases. However, more research into how mushroom proteins affect human gut microbiota and the health implications is required to gain a deeper understanding. Conclusion and Prospects Edible mushrooms are a valuable source of protein for both food and medicine. Mushrooms contain more protein than vegetables, fruits, and grains. Mushroom proteins are safer than meat proteins, with little to no risk of diseases. As a result, they meet dietary requirements: recommended dietary allowance (RDA) and protein efficiency ratio (PER). In addition, mushroom protein is of high protein quality in terms of complete essential amino acids and excellent digestibility. Consequently, mushrooms are utilized in food product fortification to increase nutritional value, particularly protein. Also, mushroom peptides, concentrate, and hydrolysates have been associated with an angiotensin-converting enzyme (ACE) inhibitory, antioxidant, antimicrobial, anticancer, and gut microbiota modulation properties. In contrast, significant progress has been made in the study of mushroom proteins from the species of Agaricus, Lentinus, and Pleurotus. However, several high-protein mushrooms, such as Tricholoma, Copyinds comatus, and Volvariella volvacea are yet to be fully utilized. Furthermore, it is widely acknowledged that the chemical structure of protein isolates such as peptides is directly related to their activities and mechanisms of action (42). However, some of the current research, particularly those on ACE-inhibitory, antioxidant, and antimicrobial activities have only been done on protein mixtures, without detailed physiochemical composition or purification and identification of active components, let alone studying the mechanisms of action. Finally, edible mushrooms provide suitable alternative protein sources for increasing protein production to meet the growing demand due to global population growth. Mushroom-based proteins can be used to combat food insecurity and malnutrition, as a meat substitute, as pharmaceutical agents, and as substrates to stimulate the gut microbiota to enhance human health. Notably, mushroom proteins are future high-quality protein substitutes that are easily accessible to both wealthy and underprivileged populations. Acknowledgements This work was financially supported by the Office of the Ministry of Higher Education, Science, Research and Innovation, and the Thailand Science Research and Innovation through the Kasetsart University Reinventing University Program 2022. Compliance with Ethical Standards Conflict of Interest The authors declare no conflicts of interest. Human and Animal Rights and Informed Consent This article does not contain any studies with human or animal subjects performed by any of the authors. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance 1. Adhikari S Schop M de Boer IJ Huppertz TJN Protein quality in perspective: a review of protein quality metrics and their applications Nutrients 2022 14 5 947 10.3390/nu14050947 35267922 2. Singh BP, Bangar SP, Albaloosh M, Ajayi FF, Mudgil P, Maqsood S. Plant-derived proteins as a sustainable source of bioactive peptides: recent research updates on emerging production methods, bioactivities, and potential application. Crit Rev Food Sci Nutr. 2022;1–22. 3. Leroy F Beal T Gregorini P McAuliffe GA Van Vliet S Hills J Nutritionism in a food policy context: the case of ‘animal protein’ Anim Prod Sci 2022 62 8 712 720 10.1071/AN21237 4. • Sá AGA, Moreno YMF, Carciofi BAM. Plant proteins as high-quality nutritional source for human diet. Trends Food Sci Technol. 2020;97:170–84. This critical review discusses the primary sources of plant proteins as well as their nutritional composition in terms of protein quantity and amino acid profile. It also aims to inspire and clarify the possibility of using plants as protein sources, emphasizing the nutritional benefits for humans and technological implications for industrial processing. 5. Yu Q Guo M Zhang B Wu H Zhang Y Zhang L Analysis of nutritional composition in 23 kinds of edible fungi J Food Qual 2020 2020 8821315 10.1155/2020/8821315 6. Krishnamoorthi R Srinivash M Mahalingam PU Malaikozhundan B Dietary nutrients in edible mushroom, Agaricus bisporus and their radical scavenging, antibacterial, and antifungal effects Process Biochem 2022 121 10 17 10.1016/j.procbio.2022.06.021 7. Ache NT Manju EB Lawrence MN Tonjock RK Nutrient and mineral components of wild edible mushrooms from the Kilum-Ijim forest, Cameroon Afr J Food Sci 2021 15 4 152 161 10.5897/AJFS2021.2089 8. •• González A, Cruz M, Losoya C, Nobre C, Loredo A, Rodríguez R, et al. Edible mushrooms as a novel protein source for functional foods. Food Funct. 2020;11(9):7400–14. This review discusses the use of mushrooms as sustainable functional food. 9. González A Nobre C Simões LS Cruz M Loredo A Rodríguez-Jasso RM Evaluation of functional and nutritional potential of a protein concentrate from Pleurotus ostreatus mushroom Food Chem 2021 346 128884 10.1016/j.foodchem.2020.128884 33401088 10. Yadav D Negi PS Bioactive components of mushrooms: processing effects and health benefits Food Res Int 2021 148 110599 10.1016/j.foodres.2021.110599 34507744 11. Ayimbila F Siriwong S Nakphaichit M Keawsompong S In vitro gastrointestinal digestion of Lentinus squarrosulus powder and impact on human fecal microbiota Sci Rep 2022 12 1 1 17 10.1038/s41598-022-06648-z 34992227 12. Fung S-Y Razif MF Bioprospecting macrofungi for biotechnological and biomedical applications Advances in macrofungi 2021 CRC Press 53 69 13. Floret C Monnet A-F Micard V Walrand S Michon C Replacement of animal proteins in food: how to take advantage of nutritional and gelling properties of alternative protein sources Crit Rev Food Sci 2021 63 920 946 10.1080/10408398.2021.1956426 14. Scialabba NE-H Livestock and future food supply scenarios Managing health livestock production and consumption 2022 Elsevier 107 121 15. Singh M Kamal S Sharma VP Status and trends in world mushroom production-III-world production of different mushroom species in 21st century 2021 Solan Mushroom Society of India 16. Kaur J Singh J Bhadariya V Gogna S Jarial S Rasane P Edible mushrooms: a source of quality protein Wild mushrooms 2022 CRC Press 169 192 17. Zhou J Chen M Wu S Liao X Wang J Wu Q A review on mushroom-derived bioactive peptides: preparation and biological activities Food Res Int 2020 134 109230 10.1016/j.foodres.2020.109230 32517923 18. Li J Ma J Fan S Mi S Zhang Y Comparison of the nutritional and taste characteristics of 5 edible fungus powders based on the composition of hydrolyzed amino acids and free amino acids J Food Qual 2022 2022 3618002 10.1155/2022/3618002 19. Dilfy SH Hanawi MJ Al-bideri AW Jalil AT Determination of chemical composition of cultivated mushrooms in Iraq with spectrophotometrically and high performance liquid chromatographic J Green Eng 2020 10 12 (1) 6200 20. Rasalanavho M Moodley R Jonnalagadda SB Elemental bioaccumulation and nutritional value of five species of wild growing mushrooms from South Africa Food Chem 2020 319 126596 10.1016/j.foodchem.2020.126596 32199145 21. Murillo W Suárez HJH Evaluation of nutritional values of wild mushrooms and spent substrate of Lentinus crinitus (L.) Fr Heliyon 2020 6 3 e03502 10.1016/j.heliyon.2020.e03502 32181387 22. McKillop K Harnly J Pehrsson P Fukagawa N Finley J FoodData Central, USDA’s Updated approach to food composition data systems Curr Dev Nutr 2021 5 Supplement_2 596 10.1093/cdn/nzab044_027 23. González A Cruz M Losoya C Nobre C Loredo A Rodríguez R Edible mushrooms as a novel protein source for functional foods Food Funct 2020 11 9 7400 7414 10.1039/D0FO01746A 32896845 24. WHO Protein and amino acid requirements in human nutrition 2007 25. Huang Q, Wang L, Zhang L, Wang Q, Liang L, Chen J, Lin J. Evaluation of amino acid characteristics and nutrient composition of six edible fungi cultivated by cinnamon[J]. Chin J Trop Crops. 2021;42(12):3529–36. 26. Li Q Liu J Shang X Li Y Zhang L Li Z Characterizing diversity based on the chemical and nutritional composition of shiitake culinary-medicinal mushroom Lentinula edodes (Agaricomycetes) commonly cultivated in China Int J Med Mushrooms 2021 23 8 51 64 10.1615/IntJMedMushrooms.2021039240 34587425 27. Cai J Chen Z Wei Wu Lin Q Liang Y High animal protein diet and gut microbiota in human health Crit Rev Food Sci Nutr 2022 62 22 6225 6237 10.1080/10408398.2021.1898336 33724115 28. Liaotrakoon W Liaotrakoon V Amino acid profile, phytochemical composition and antimicrobial activities of edible tropical bolete mushroom (Phlebopus colossus (R. Heim) Singer) J Food Meas Charact 2022 16 3 1967 1973 10.1007/s11694-022-01331-3 29. Ha SY Jung JY Park HM Yang J-K Comparison of the metabolic profile of the mycelia and fruiting bodies of artificially cultured Cordyceps militaris J Mushroom 2022 20 1 13 21 30. Reis GC Guidi LR Fernandes C Godoy HT Gloria MBA UPLC-UV method for the quantification of free amino acids, bioactive amines, and ammonia in fresh, cooked, and canned mushrooms Food Anal Methods 2020 13 8 1613 1626 10.1007/s12161-020-01777-5 31. Sissons J Davila M Du X Sautéing and roasting effect on free amino acid profiles in portobello and shiitake mushrooms, and the effect of mushroom-and cooking-related volatile aroma compounds on meaty flavor enhancement Int J Gastron Food Sci 2022 28 100550 10.1016/j.ijgfs.2022.100550 32. Nam M Choi JY Kim M-S Metabolic profiles, bioactive compounds, and antioxidant capacity in Lentinula edodes cultivated on log versus sawdust substrates Biomolecules 2021 11 11 1654 10.3390/biom11111654 34827654 33. Feng Y Xin G Wei Y Xu H Sun L Hou Z Comparison of the umami taste and aroma of dried Suillus granulatus packed using four different packaging methods Food Chem 2022 366 130570 10.1016/j.foodchem.2021.130570 34311238 34. Thakur M Advances in mushroom production: key to food, nutritional and employment security: Aareview Indian Phytopathol 2020 73 3 377 395 10.1007/s42360-020-00244-9 35. Schimbator M Culețu A Susman I Duță DE Digestibility of proteins from different sources Ann Univ Dunarea Jos Galati Fascicle VI Food Technol 2020 44 2 43 50 10.35219/foodtechnology.2020.2.03 36. Reis GC Dala-Paula BM Tavano OL Guidi LR Godoy HT Gloria MBA In vitro digestion of spermidine and amino acids in fresh and processed Agaricus bisporus mushroom Food Res Int 2020 137 109616 10.1016/j.foodres.2020.109616 33233206 37. Fraile-Fabero R Ozcariz-Fermoselle MV Oria-de-Rueda-Salgueiro JA Garcia-Recio V Cordoba-Diaz D del P. Jiménez-López M Differences in antioxidants, polyphenols, protein digestibility and nutritional profile between Ganoderma lingzhi from industrial crops in Asia and Ganoderma lucidum from cultivation and Iberian origin Foods 2021 10 8 1750 10.3390/foods10081750 34441528 38. Venturella G Ferraro V Cirlincione F Gargano ML Medicinal mushrooms: bioactive compounds, use, and clinical trials Int J Mol Sci 2021 22 2 634 10.3390/ijms22020634 33435246 39. Tu J Brennan MA Wu G Bai W Cheng P Tian B Delivery of phenolic compounds, peptides and β-glucan to the gastrointestinal tract by incorporating dietary fibre-rich mushrooms into sorghum biscuits Foods 2021 10 8 1812 10.3390/foods10081812 34441591 40. Cerón-Guevara MI Rangel-Vargas E Lorenzo JM Bermúdez R Pateiro M Rodriguez JA Effect of the addition of edible mushroom flours (Agaricus bisporus and Pleurotus ostreatus) on physicochemical and sensory properties of cold-stored beef patties J Food Process Preserv 2020 44 3 e14351 10.1111/jfpp.14351 41. Al-zamani Z, Kumar A, Al-dalali S, Aleryani H, Abdo A. Development of protein-enriched cake incorporated with mushroom powder (Agaricus bisporus). Int J Food Sci Nutr. 2022;7(2):23–28. 42. Wang L Zhao H Brennan M Guan W Liu J Wang M In vitro gastric digestion antioxidant and cellular radical scavenging activities of wheat-shiitake noodles Food Chem 2020 330 127214 10.1016/j.foodchem.2020.127214 32521398 43. Kolawole FL Akinwande BA Ade-Omowaye BI Physicochemical properties of novel cookies produced from orange-fleshed sweet potato cookies enriched with sclerotium of edible mushroom (Pleurotus tuberregium) J Saudi Soc Agric Sci 2020 19 2 174 178 44. Parvin R Farzana T Mohajan S Rahman H Rahman SS Quality improvement of noodles with mushroom fortified and its comparison with local branded noodles NFS J 2020 20 37 42 10.1016/j.nfs.2020.07.002 45. Oosone S Kashiwaba A Yanagihara N Yoshikawa J Kashiwagi Y Maehashi K The role of amylolytic and proteolytic enzyme activities of vegetables, fruits, and edible fungi in flavor enhancement during cooking Int J Gastron 2020 22 100264 46. Yuan X Jiang W Zhang D Liu H Sun B Textural, sensory and volatile compounds analyses in formulations of sausages analogue elaborated with edible mushrooms and soy protein isolate as meat substitute Foods 2021 11 1 52 10.3390/foods11010052 35010178 47. Cho SY Ryu GH Effects of oyster mushroom addition on physicochemical properties of full fat soy-based meat analog by extrusion process Ind Food Eng 2021 25 2 85 94 48. Mohamad Mazlan M Talib RA Chin NL Shukri R Taip FS Mohd Nor MZ Physical and microstructure properties of oyster mushroom-soy protein meat analog via single-screw extrusion Foods 2020 9 8 1023 10.3390/foods9081023 32751949 49. Altaf U Hashmi S Sharma YP Therapeutic potential of mushroom bioactive nutraceuticals Biology, cultivation and applications of mushrooms 2022 Singapore Springer 357 386 50. Zhang Y Zhou R Liu F Ng TB Purification and characterization of a novel protein with activity against non-small-cell lung cancer in vitro and in vivo from the edible mushroom Boletus edulis Int J Biol Macromol 2021 174 77 88 10.1016/j.ijbiomac.2021.01.149 33508361 51. Abdullah E Abidin NZ Aminudin N Abdullah N Characterization of cytotoxic proteins from king tuber oyster medicinal mushroom, Pleurotus tuber-regium (Agaricomycetes), sclerotium for human breast MDA-MB-231 cancer cells Int J Med Mushrooms 2022 24 5 27 40 10.1615/IntJMedMushrooms.2021041548 35442593 52. Zhang Y Zhang Y Gao W Zhou R Liu F Ng TB A novel antitumor protein from the mushroom Pholiota nameko induces apoptosis of human breast adenocarcinoma MCF-7 cells in vivo and modulates cytokine secretion in mice bearing MCF-7 xenografts Int J Biol Macromol 2020 164 3171 3178 10.1016/j.ijbiomac.2020.08.187 32858105 53. Oli AN Edeh PA Al-Mosawi RM Mbachu NA Al-Dahmoshi HO Al-Khafaji NS Evaluation of the phytoconstituents of Auricularia auricula-judae mushroom and antimicrobial activity of its protein extract Eur J Integr Med 2020 38 101176 10.1016/j.eujim.2020.101176 32834875 54. Bansal V Tyagi S Ghosh K Gupta A Extraction of protein from mushroom and determining its antioxidant and anti-inflammatory potential Res J Pharm Technol 2020 13 12 6017 6021 10.5958/0974-360X.2020.01049.5 55. Hou Y Wu Z Dai Z Wang G Wu G Protein hydrolysates in animal nutrition Bioactive peptides from food 2022 CRC Press 209 232 56. Wu S Chen M Liao X Huang R Wang J Xie Y Protein hydrolysates from Pleurotus geesteranus obtained by simulated gastrointestinal digestion exhibit neuroprotective effects in H2O2-injured PC12 cells J Food Biochem 2022 46 4 e13879 10.1111/jfbc.13879 34309037 57. Goswami B Majumdar S Das A Barui A Bhowal J Evaluation of bioactive properties of Pleurotus ostreatus mushroom protein hydrolysate of different degree of hydrolysis LWT 2021 149 111768 10.1016/j.lwt.2021.111768 58. Wu S Chen M Liao X Huang R Wang J Xie Y Protein hydrolysates from Pleurotus geesteranus obtained by simulated gastrointestinal digestion exhibit neuroprotective effects in H2O2-injured PC12 cells J Food Biochem 2022 46 4 e13879 10.1111/jfbc.13879 34309037 59. Liao X Zhu Z Wu S Chen M Huang R Wang J Preparation of antioxidant protein hydrolysates from Pleurotus geesteranus and their protective effects on H2O2 oxidative damaged PC12 cells Molecules 2020 25 22 5408 10.3390/molecules25225408 33227951 60. Krobthong S Choowongkomon K Suphakun P Kuaprasert B Samutrtai P Yingchutrakul Y The anti-oxidative effect of Lingzhi protein hydrolysates on lipopolysaccharide-stimulated A549 cells Food Biosci 2021 41 101093 10.1016/j.fbio.2021.101093 61. López-Martínez MI Miguel M Garcés-Rimón M Protein and sport: alternative sources and strategies for bioactive and sustainable sports nutrition Front Nutr 2022 9 926043 10.3389/fnut.2022.926043 35782926 62. Hu X, Zhang Q, Zhang Q, Ding J, Liu Y, Qin W, et al. An updated review of functional properties, debittering methods, and applications of soybean functional peptides. Crit Rev Food Sci. 2022;1–16. 63. Bhandari D Rafiq S Gat Y Gat P Waghmare R Kumar V A review on bioactive peptides: physiological functions, bioavailability and safety Int J Pept Res Ther 2020 26 1 139 150 10.1007/s10989-019-09823-5 64. Montesano D Gallo M Blasi F Cossignani L Biopeptides from vegetable proteins: new scientific evidences Curr Opin Food Sci 2020 31 31 37 10.1016/j.cofs.2019.10.008 65. Sonklin C Alashi MA Laohakunjit N Kerdchoechuen O Aluko RE Identification of antihypertensive peptides from mung bean protein hydrolysate and their effects in spontaneously hypertensive rats J Funct Foods 2020 64 103635 10.1016/j.jff.2019.103635 66. Paisansak S Sangtanoo P Srimongkol P Saisavoey T Reamtong O Choowongkomon K Angiotensin-I converting enzyme inhibitory peptide derived from the shiitake mushroom (Lentinula edodes) J Food Sci Technol 2021 58 1 85 97 10.1007/s13197-020-04517-z 33505054 67. Li W Chen W Ma H Wu D Zhang Z Yang Y Structural characterization and angiotensin-converting enzyme (ACE) inhibitory mechanism of Stropharia rugosoannulata mushroom peptides prepared by ultrasound Ultrason Sonochem 2022 88 106074 10.1016/j.ultsonch.2022.106074 35753137 68. Wang R Yun J Wu S Bi Y Zhao FJF Optimisation and characterisation of novel angiotensin-converting enzyme inhibitory peptides prepared by double enzymatic hydrolysis from Agaricus bisporus Scraps Foods 2022 11 3 394 10.3390/foods11030394 35159545 69. Kheng YS Jeng YL Nor MM Jia GB The analysis of Angiotensin-I Converting Enzyme (ACE) by maitake (Grifrola frondosa) mycelia J Trop Resour Sustain Sci 2020 8 2 69 72 70. Kurek M Benaida-Debbache N Elez Garofulić I Galić K Avallone S Voilley A Antioxidants and bioactive compounds in food: critical review of issues and prospects Antioxidants 2022 11 4 742 10.3390/antiox11040742 35453425 71. Qu H Sun Q Pang J Ding D Bai J Molecular structure design of polyhydroxyl antioxidants and mechanism of hydroxyl radical scavenging reaction Sch J Agric Vet Sci 2022 4 54 59 72. Arias A Feijoo G Moreira MT Exploring the potential of antioxidants from fruits and vegetables and strategies for their recovery Innov Food Sci Emerg Technol 2022 77 102974 10.1016/j.ifset.2022.102974 73. Yang X Sun Z Wang W Zhou Q Shi G Wei F Developmental toxicity of synthetic phenolic antioxidants to the early life stage of zebrafish Sci Total Environ 2018 643 559 568 10.1016/j.scitotenv.2018.06.213 29945090 74. Wongaem A Reamtong O Srimongkol P Sangtanoo P Saisavoey T Karnchanatat A Antioxidant properties of peptides obtained from the split gill mushroom (Schizophyllum commune) J Food Sci Technol 2021 58 2 680 691 10.1007/s13197-020-04582-4 33568862 75. Sangtitanu T Sangtanoo P Srimongkol P Saisavoey T Reamtong O Karnchanatat AJF Peptides obtained from edible mushrooms: Hericium erinaceus offers the ability to scavenge free radicals and induce apoptosis in lung cancer cells in humans Food Funct 2020 11 6 4927 4939 10.1039/D0FO00227E 32432266 76. Song R Liang T Shen Q Liu J Lu Y Tang C The optimization of production and characterization of antioxidant peptides from protein hydrolysates of Agrocybe aegerita LWT 2020 134 109987 10.1016/j.lwt.2020.109987 77. Kimatu BM Fang D Zhao L Hu Q Agaricus bisporus peptide fractions confer cytoprotective ability against hydrogen peroxide-induced oxidative stress in HepG2 and Caco-2 cells J Food Meas Charact 2020 14 5 2503 2519 10.1007/s11694-020-00497-y 78. • Landi N, Clemente A, Pedone PV, Ragucci S, Di Maro A. An updated review of bioactive peptides from mushrooms in a well-defined molecular weight range. Toxins. 2022;14(2):84. This review reported on the present state of bioactive peptides isolated and described from mushrooms over the last 20 years, with 'peptide' defined as a succession of 2 to 100 amino acid residues. 79. Xiong C Li P Luo Q Phan CW Li Q Jin X Induction of apoptosis in HeLa cells by a novel peptide from fruiting bodies of Morchella importuna via the mitochondrial apoptotic pathway Evid Based Complementary Altern Med 2021 2021 5563367 80. Kaprasob R Khongdetch J Laohakunjit N Selamassakul O Kaisangsri N Isolation and characterization, antioxidant, and antihypertensive activity of novel bioactive peptides derived from hydrolysis of King Boletus mushroom LWT 2022 160 113287 10.1016/j.lwt.2022.113287 81. Khongdetch J Laohakunjit N Kaprasob R King Boletus mushroom-derived bioactive protein hydrolysate: characterisation, antioxidant, ACE inhibitory and cytotoxic activities Int J Food Sci Technol 2022 57 3 1399 1410 10.1111/ijfs.15100 82. Oso BJ Ogidi CO Repositioning of fungal-based peptides as modulators of angiotensin-converting enzyme-related carboxypeptidase, SARS-coronavirus HR2 domain, and coronavirus disease 2019 main protease J Transl Intern Med 2021 9 3 190 199 10.2478/jtim-2021-0038 83. Rodríguez-Pastén A Pérez-Hernández N Añorve-Morga J Jiménez-Alvarado R Cariño-Cortés R Sosa-Lozada T The activity of prebiotics and probiotics in hepatogastrointestinal disorders and diseases associated with metabolic syndrome Int J Mol Sci 2022 23 13 7229 10.3390/ijms23137229 35806234 84. Huang Y Gao Y Pi X Zhao S Liu W In vitro hepatoprotective and human gut microbiota modulation of polysaccharide-peptides in Pleurotus citrinopileatus Front Cell Infect Microbiol 2022 12 892049 10.3389/fcimb.2022.892049 35669115 85. Wu S Wu Q Wang J Li Y Chen B Zhu Z Novel selenium peptides obtained from selenium-enriched Cordyceps militaris alleviate neuroinflammation and gut microbiota dysbacteriosis in LPS-injured mice J Agric Food Chem 2022 70 10 3194 3206 10.1021/acs.jafc.1c08393 35238567 86. Li M Lv R Xu X Ge Q Lin S Tricholoma matsutake-derived peptides show gastroprotective effects against ethanol-induced acute gastric injury J Agric Food Chem 2021 69 49 14985 14994 10.1021/acs.jafc.1c07050 34866395 87. Li X Zhang ZH Zabed HM Yun J Zhang G Qi X An insight into the roles of dietary tryptophan and its metabolites in intestinal inflammation and inflammatory bowel disease Mol Nutr Food Res 2021 65 5 2000461 10.1002/mnfr.202000461 88. Ragucci S Landi N Russo R Valletta M Pedone PV Chambery A Ageritin from pioppino mushroom: the prototype of ribotoxin-like proteins, a novel family of specific ribonucleases in edible mushrooms Toxins 2021 13 4 263 10.3390/toxins13040263 33917246 89. Lampitella E Landi N Oliva R Gaglione R Bosso A De Lise F Toxicity and membrane perturbation properties of the ribotoxin-like protein Ageritin J Biochem 2021 170 4 473 482 10.1093/jb/mvab062 33993266 90. Xu L Geng X Chang M Meng J Wang H Ng TB A novel ribonuclease with HIV-1 reverse transcriptase inhibitory activity purified from the field Blewit Mushroom Lepista personata (Agaricomycetes) Int J Med Mushrooms 2020 22 10 991 1000 10.1615/IntJMedMushrooms.2020035810 33426828 91. Aborode AT Ogunsola SO Adeyemo AO A crisis within a crisis: Covid-19 and hunger in African children Am J Trop Med Hyg 2021 104 1 30 10.4269/ajtmh.20-1213 33236705 92. Grimblatt V The challenge of agriculture: increase the productivity in a sustainable way 2021 Forum on specification & Design Languages (FDL) 2021 IEEE 93. Padhani ZA Das JK Akhtar S Ismail T Bhutta ZA Tackling protein-calorie malnutrition during world crises Ann Nutr Metab 2022 78 1 6 16 94. Li M Yu L Zhao J Zhang H Chen W Zhai Q Role of dietary edible mushrooms in the modulation of gut microbiota J Funct Foods 2021 83 104538 10.1016/j.jff.2021.104538 95. Santo RE Kim BF Goldman SE Dutkiewicz J Biehl E Bloem MW Considering plant-based meat substitutes and cell-based meats: a public health and food systems perspective Front Sustain Food Syst 2020 4 134 10.3389/fsufs.2020.00134 96. Kurek MA Onopiuk A Pogorzelska-Nowicka E Szpicer A Zalewska M Półtorak A Novel protein sources for applications in meat-alternative products–insight and challenges Foods 2022 11 7 957 10.3390/foods11070957 35407043 97. Lee HJ Yong HI Kim M Choi Y-S Jo C Status of meat alternatives and their potential role in the future meat market–a review Asian Australas J Anim Sci 2020 33 10 1533 10.5713/ajas.20.0419 32819080 98. Stoffel F de Oliveira SW Fontana RC Camassola M Use of Pleurotus albidus mycoprotein flour to produce cookies: evaluation of nutritional enrichment and biological activity Innov Food Sci Emerg Technol 2021 68 102642 10.1016/j.ifset.2021.102642 99. Hashempour-Baltork F Hosseini SM Assarehzadegan MA Khosravi-Darani K Hosseini H Safety assays and nutritional values of mycoprotein produced by Fusarium venenatum IR372C from date waste as substrate J Sci Food 2020 100 12 4433 4441 10.1002/jsfa.10483 100. Singh M Trivedi N Enamala MK Kuppam C Parikh P Nikolova MP Plant-based meat analogue (PBMA) as a sustainable food: a concise review Eur Food Res Technol 2021 247 10 2499 2526 10.1007/s00217-021-03810-1 101. Coelho MO Monteyne AJ Dunlop MV Harris HC Morrison DJ Stephens FB Mycoprotein as a possible alternative source of dietary protein to support muscle and metabolic health Nutr Rev 2020 78 6 486 497 10.1093/nutrit/nuz077 31841152 102. Cherta-Murillo A Frost GS The association of mycoprotein-based food consumption with diet quality, energy intake and non-communicable diseases’ risk in the UK adult population using the National Diet and Nutrition Survey (NDNS) years 2008/2009–2016/2017: a cross-sectional study Br J Nutr 2022 127 11 1685 1694 10.1017/S000711452100218X 34134798 103. Singh RS Walia AK Kennedy JF Mushroom lectins in biomedical research and development Int J Biol Macromol 2020 151 1340 1350 10.1016/j.ijbiomac.2019.10.180 31751693 104. Tirta Ismaya W Tjandrawinata RR Rachmawati H Lectins from the edible mushroom Agaricus bisporus and their therapeutic potentials Molecules 2020 25 10 2368 10.3390/molecules25102368 32443732 105. El-Maradny YA El-Fakharany EM Abu-Serie MM Hashish MH Selim HS Lectins purified from medicinal and edible mushrooms: insights into their antiviral activity against pathogenic viruses Int J Biol Macromol 2021 179 239 258 10.1016/j.ijbiomac.2021.03.015 33676978 106. Rezvani V Pourianfar HR Mohammadnejad S Madjid Ansari A Farahmand L Anticancer potentiality and mode of action of low-carbohydrate proteins and peptides from mushrooms Appl Microbiol Biotechnol 2020 104 16 6855 6871 10.1007/s00253-020-10707-8 32556413 107. Balakrishnan K Dhanasekaran D Krishnaraj V Anbukumaran A Ramasamy T Manickam M Edible mushrooms: a promising bioresource for prebiotics Advances in probiotics 2021 Elsevier 81 97 108. You SW Hoskin RT Komarnytsky S Moncada M Mushrooms as functional and nutritious food ingredients for multiple applications ACS Food Sci Technol 2022 2 8 1184 1195 10.1021/acsfoodscitech.2c00107 109. Zheng S Zhu N Shi C Zheng HJP Genomic data mining approaches for the discovery of anticancer peptides from Ganoderma sinense Phytochemistry 2020 179 112466 10.1016/j.phytochem.2020.112466 32823212 110. Ragucci S Landi N Russo R Valletta M Citores L Iglesias R Effect of an additional N-terminal methionyl residue on enzymatic and antifungal activities of Ageritin purified from Agrocybe aegerita fruiting bodies Int J Biol Macromol 2020 155 1226 1235 10.1016/j.ijbiomac.2019.11.090 31726122 111. Jaloot AS Owaid MN Naeem GA Muslim RF Mycosynthesizing and characterizing silver nanoparticles from the mushroom Inonotus hispidus (Hymenochaetaceae), and their antibacterial and antifungal activities Environ Nanotechnol Monit Manag 2020 14 100313 112. Zhang L Lu Y Feng X Liu Q Li Y Hao J Hepatoprotective effects of Pleurotus ostreatus protein hydrolysates yielded by pepsin hydrolysis Catalysts 2020 10 6 595 10.3390/catal10060595 113. Li M Ge Q Du H Jiang P Bao Z Chen D Potential mechanisms mediating the protective effects of Tricholoma matsutake-derived peptides in mitigating DSS-induced colitis J Agric Food Chem 2021 69 19 5536 5546 10.1021/acs.jafc.1c01908 33955220 114. Kumar H Bhardwaj K Sharma R Nepovimova E Cruz-Martins N Dhanjal DS Potential usage of edible mushrooms and their residues to retrieve valuable supplies for industrial applications J Fungi 2021 7 6 427 10.3390/jof7060427
PMC010xxxxxx/PMC10091317.txt	==== Front Onkologie Die Onkologie 2731-7226 2731-7234 Springer Medizin Heidelberg 1340 10.1007/s00761-023-01340-x Journal Club Einfluss der COVID-19-Pandemie auf Krebsvorsorgeuntersuchungen Impact of the COVID-19 pandemic on cancer screeningBochtler Jonathan Hartmann Milan J. M. Alakus Hakan [email protected] grid.411097.a 0000 0000 8852 305X Klinik und Poliklinik für Allgemein‑, Viszeral‑, Tumor- und Transplantationschirurgie, Universitätsklinikum Köln (AöR), Kerpener Str. 62, 50937 Köln, Deutschland 12 4 2023 2023 29 5 455456 3 3 2023 © The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature 2023, korrigierte Publikation 2023 This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. issue-copyright-statement© Springer Medizin Verlag GmbH, ein Teil von Springer Nature 2023 ==== Body pmcOriginalpublikation Zhang X, Elsaid MI, DeGraffinreid C, Champion VL, Paskett ED (2023) Impact of COVID-19 on behaviors across the cancer control continuum in Ohio group. Impact of the COVID-19 pandemic on cancer screening delays. J Clin Oncol. 10.1200/JCO.22.01704. Hintergrund. COVID-19 hat die Gesellschaft in vielerlei Hinsicht beeinflusst und vor große Herausforderungen gestellt. So hat sie in den USA dazu geführt, dass die Menge an Krebsvorsorgeuntersuchungen vor allem in der Anfangsphase der Pandemie dramatisch sank (bis zu 86–94 % verglichen mit den Vorjahren; [1]) und auch die neu gestellten Krebsdiagnosen abnahmen (bis zu 19–78 %; [2]). Aufgrund dieser Missstände geht man davon aus, dass in den nächsten Jahrzehnten in den USA ungefähr 10.000 zusätzliche Krebstodesfälle durch Brust- und kolorektale Karzinome auftreten werden [3]. In ohnehin benachteiligten Bevölkerungsgruppen wie Menschen aus geringeren Bildungsschichten, Menschen asiatischer Herkunft, Hispanoamerikanerinnen oder Afroamerikanerinnen könnten sich diese Verzögerungen in der Krebsvorsorge besonders deutlich manifestieren. Das Ziel dieser Studie war es daher, die Unterschiede zwischen verschiedenen Bevölkerungsgruppen bei Verzögerungen in der Krebsvorsorge zu identifizieren. Methoden. Diese Studie wurde von einem Konsortium von 17 Krebszentren, dem IC‑4 (Impact of COVID-19 on the Cancer Continuum Consortium), in den Bundesstaaten Ohio und Indiana durchgeführt. Die Teilnehmerinnen der Studie wurden aus einer Gruppe von Personen und ihren Bezugspersonen rekrutiert, die an früheren Studien teilnahmen. Die Datenerhebung erfolgte mittels Online‑/Telefon- und Papierfragebögen. Dabei wurden demografische Parameter wie Alter, Geschlecht (Mann oder Frau), ethnische Abstammung (weißer, asiatischer, schwarzer/afroamerikanischer oder „anderer“ Abstammung mit Möglichkeit der Mehrfachauswahl), Familienstand (Single oder nie verheiratet, verheiratet oder in Partnerschaft lebend, geschieden, getrennt, verwitwet oder „sonstige“), Versicherungsstatus (privat, öffentlich, beides) und Urbanität des Wohnorts (urban, ländlich) erfasst. Grundsätzlich wurde gefragt, ob die Probandinnen zwischen März und Dezember 2020 eine Krebsvorsorgeuntersuchung geplant hatten und ob diese aufgrund der COVID-19-Pandemie verschoben wurde. Ergebnisse. 7115 Teilnehmerinnen im durchschnittlichen Alter von 57,3 Jahren wurden in die Studie inkludiert. Davon lebten 95,8 % in Ohio, die restlichen Teilnehmerinnen in Indiana. 75 % der Teilnehmerinnen waren Frauen, 89 % waren nichtlateinamerikanisch weiß, 14 % waren gesetzlich versichert und 34 % lebten in ländlichen Gebieten. Insgesamt waren die Teilnehmerinnen, die eine Krebsvorsorgeuntersuchung planten (60 %), eher jünger, häufiger weiblich, hatten einen höheren Bildungsgrad, waren eher privat versichert und lebten auf dem Land. Im Vergleich zu nichtlateinamerikanisch weißen Frauen hatten schwarze Frauen eine geringere Aussicht auf eine Verzögerung ihrer Mammographie (Odds Ratio [OR] 0,60; 95 %-Konfidenzintervall [CI] 0,39–0,94), lateinamerikanische Frauen höhere Aussicht auf Vertagung ihres Pap(Papanicolaou)-Test (OR 2,46; 95 %-CI 1,34–4,55) und Frauen aus anderen Ethnizitäten höhere Wahrscheinlichkeit auf eine Verzögerung sowohl beim Pap-Test (OR 2,38; 95 %-CI 1,14–4,02) als auch beim HPV-Test (OR 5,37; 95 %-CI 1,44–19,97). Alles zusammengenommen wurden 36,2 % der Koloskopien, 27,1 % der Pap-Abstriche, 26,8 % der HPV-Tests, 24,5 % der Mammographien und 11,3 % der Untersuchungen auf Blut im Stuhl verschoben. Zusätzlich zeigte sich noch, dass Frauen in höherem Lebensalter Mammographien mit geringerer Wahrscheinlichkeit als jüngere verschoben. Diskussion. In dieser Studie wurden erstmalig die Verzögerungen der Krebsvorsorgeuntersuchungen im Kontext demografischer Unterschiede erfasst, wobei 11–36 % der geplanten Krebsvorsorgeuntersuchungen zwischen März und Dezember 2020 verschoben wurden. Eine Krebsvorsorgeuntersuchung war eher von jüngeren, verwitweten, getrennten oder geschiedenen Teilnehmer*innen geplant sowie von solchen mit höherer Bildung, höherem Einkommen, privater Versicherung oder Wohnsitz im ländlichen Umfeld. Koloskopien wurden am häufigsten verschoben (36,2 %), gefolgt von Pap-Abstrichen, HPV-Tests und Mammographien. In anderen Studien wurde zusätzlich ein allgemeiner Anstieg von Tests auf Blut im Stuhl festgestellt [4, 5]. Dies könnte möglicherweise eine Gegenregulation zu den Koloskopien sein, die häufiger verschoben wurden. Bereits in einer vorherigen Erhebung konnte gezeigt werden, dass vor allem Menschen geringeren Bildungsstands und ethnische Minderheiten von zusätzlichen Verzögerungen in der Krebsvorsorge im Rahmen der COVID-19-Pandemie betroffen sind [4]. Dies ist vor allem deshalb besorgniserregend, weil diese Bevölkerungsgruppen (z. B. Hispanoamerikaner oder Ureinwohner) ein erhöhtes Risiko für Zervixkarzinome zeigten [4]. Kommentar Auch wenn die Ergebnisse der Studie möglicherweise nicht uneingeschränkt auf andere Gebiete der USA oder der westlichen Welt anwendbar sind und die Auswertung ausschließlich auf einer Befragung fundierte, zeigen sie eindrücklich, welchen großen Einfluss demografische Faktoren auf eine adäquate Krebsfrüherkennung im Rahmen der COVID-19-Pandemie haben können. Fazit für die Praxis Das Aufklären vulnerabler Patientengruppen über die Relevanz von Krebsvorsorgeuntersuchungen durch Gesundheitsdienstleister könnte einen positiven Einfluss auf die Krebsfrüherkennungsraten haben und Krebstote verhindern. Vor allem Gesellschaftsgruppen, die ohnehin bei der Krebsvorsorge benachteiligt waren, erlebten eine weitere Verschlechterung der Situation durch die COVID-19-Pandemie. Interessenkonflikt J. Bochtler, M.J. Hartmann und H. Alakus geben an, dass kein Interessenkonflikt besteht. QR-Code scannen & Beitrag online lesen Die Originalversion dieses Beitrags wurde korrigiert: Der Name des Autors Jonathan Bochtler wurde in diesem Artikel falsch geschrieben. Change history 6/13/2023 Zu diesem Beitrag wurde ein Erratum veröffentlicht: 10.1007/s00761-023-01368-z ==== Refs Literatur 1. Epic Health Research Network Preventive cancer screenings during COVID-19 pandemic. https://epicresearchblob.blob.core.windows.net/cms-uploads/pdfs/Preventive-Cancer-Screenings-during-COVID-19-Pandemic.pdf. Zugriffsdatum Februar 2023 2. Bakouny Z Paciotti M Schmidt AL Cancer screening tests and cancer diagnoses during the COVID-19 pandemic JAMA Oncol 2021 7 458 460 10.1001/jamaoncol.2020.7600 33443549 3. Sharpless NE COVID-19 and cancer Science 2020 368 1290 10.1126/science.abd3377 32554570 4. Fedewa SA Star J Bandi P Changes in cancer screening in the US during the COVID-19 pandemic JAMA Netw Open 2022 5 2215490 10.1001/jamanetworkopen.2022.15490 5. Jaklevic MC Pandemic spotlights in-home colon cancer screening tests JAMA 2021 325 116 118
PMC010xxxxxx/PMC10098989.txt	==== Front Inn Med (Heidelb) Inn Med (Heidelb) Innere Medizin (Heidelberg, Germany) 2731-7080 2731-7099 Springer Medizin Heidelberg 37052623 1501 10.1007/s00108-023-01501-5 Medizin Aktuell Die Grenzen der Inneren Medizin The limits of internal medicineLerch Markus M. [email protected] grid.411095.8 0000 0004 0477 2585 Ärztliches Direktorat, LMU Klinikum München, Marchioninistraße 15, 81377 München, Deutschland 13 4 2023 2023 64 Suppl 2 135143 1 3 2023 © The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature 2023 This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. „Die Grenzen der Inneren Medizin“ bildeten das Kongressmotto des 128. Internistenkongresses im Jahr 2022 in Wiesbaden. In seiner Präsidentenrede ging Prof. Lerch auf vier Aspekte dieses Mottos ein: ärztliches Handeln am Lebensende, Lektionen aus der Coronapandemie, Defizite in der Digitalisierung des deutschen Gesundheitswesens und der deutsche Sonderweg beim Datenschutz in der Medizin. Anhand von Daten aus Kanada, der Schweiz und den Niederlanden, in denen Sterbehilfe praktiziert wird, appellierte Prof. Lerch an Internistinnen und Internisten – v. a. hausärztlich tätige –, sich nach dem Urteil des Bundesverfassungsgerichtes intensiv mit dieser Thematik auseinanderzusetzen. Mit Blick auf die Entwicklungen der Coronapandemie diskutierte er Gründe der fehlenden Impfbereitschaft in Teilen der Gesellschaft sowie die Frage, warum v. a. nicht klinisch tätige und kaum patientenversorgende Fächer die Diskussion um Coronaschutzmaßnahmen in Deutschland geprägt haben. Ein weiterer Schwerpunkt der Rede war die unzureichende Digitalisierung des deutschen Gesundheitswesens, das im Hinblick auf seine digitale Transformation im internationalen Vergleich deutlich zurückliegt. Ärztinnen und Ärzte müssten sich stärker in die digitale Transformation einbringen, um das Gesundheitswesen zum Wohle der Patienten umzugestalten. Der deutsche Sonderweg bei der Auslegung der Datenschutz-Grundverordnung (DSGVO) bedarf einer gesetzlichen Regelung, die eine pragmatische und fortschrittliche Nutzung von Patientendaten für die Krankenversorgung und die medizinische Forschung erlaubt. “The limits of internal medicine” was the congress motto of the 128th Congress of the German Society of Internal Medicine in Wiesbaden in 2022. In his presidential address Prof. Lerch focused on four aspects of this motto: physician-assisted suicide, lessons from the corona pandemic, deficits in the digitalization of the German healthcare system and the German Sonderweg in applying EU regulations for patient data protection. Using data from Canada, Switzerland and the Netherlands, where different forms of physician-assisted suicide are practiced, Prof. Lerch appealed to internists, specifically in family practices, to confront this issue in view of a German Supreme Court ruling. With respect to the development of the corona pandemic he discussed the root causes of the opposition to vaccination in parts of society as well as the question why non-clinically active and only few clinical disciplines have shaped the discussion about corona protection measures in Germany. Another focus of his speech was the insufficient digital maturity of the German healthcare system, which clearly lags behind other countries with respect to digital transformation. Physicians need to become more involved in the digital transformation in order to reorganize the healthcare system for the benefit of the patients. The German Sonderweg in the application of the General Data Protection Regulation (GDPR) requires a new legal framework to enable a pragmatic and progressive use of patient data for medical research and patient safety. Schlüsselwörter Sterbehilfe COVID-19-Pandemie Datenschutz Digitalisierung Datenschutz-Grundverordnung Keywords Assisted suicide COVID-19 pandemic Data protection Digitalization General Data Protection Regulation issue-copyright-statement© Springer Medizin Verlag GmbH, ein Teil von Springer Nature 2023 ==== Body pmcMeine sehr verehrten Damen und Herren! Liebe Kolleginnen und Kollegen! Heute an dieser Stelle zu stehen, empfinde ich als wirklich großes Privileg. Zum einen, weil bis vor wenigen Wochen noch unklar war, ob die seit 2 Jahren in Wellen verlaufende Coronapandemie oder der am 24.02.2022 begonnene russische Angriffskrieg auf die Ukraine es überhaupt erlauben würden, diesen Kongress und diese festliche Abendveranstaltung im prächtigsten Festsaal des Landes in Präsenz veranstalten zu können. Zum anderen, weil ich nicht sicher war, ob es mir selbst gelingen würde, dem Virus trotz Impfung und Auffrischung einer Ansteckung durch die Omikronvariante zu entgehen. Wenn Sie in das Amt der Vorsitzenden der Deutschen Gesellschaft für Innere Medizin, deren Gründung sich in diesem Jahr zum 140. Mal jährt, gewählt werden, dann wird Ihnen die Chance gegeben, für exakt ein Jahr Themenschwerpunkte zu setzen, von denen Sie glauben, dass sie eine breite Öffentlichkeit verdienen, dass sie unter Internistinnen und Internisten diskutiert und in der Medizin berücksichtigt und behandelt werden sollten. Bei einer Fachgesellschaft mit 28.000 Mitgliedern hat das Gewicht und bedeutet eine große Verantwortung. Es ist aber auch eine große Ehre, diese Aufgabe übernehmen zu dürfen. Mein Thema in den vergangenen 12 Monaten und das Motto des Kongresses sind „Die Grenzen der Inneren Medizin“. Das sind sehr vielfältige Grenzen, und ich habe vier persönliche Anliegen in der Zeit der Präsidentschaft als Schwerpunkte gesetzt oder versucht, für diese zumindest Aufmerksamkeit zu erzeugen. Auf diese Schwerpunkte werde ich heute Abend eingehen: Ich beginne mit den Grenzen des ärztlichen Handelns am Lebensende – und das ist wahrscheinlich die härteste Herausforderung, von der ich glaube, dass wir uns als Ärzte mit ihr auseinandersetzen müssen. Ich möchte als Nächstes über einige Lektionen sprechen, die ich persönlich in der Coronapandemie gelernt habe. Im Weiteren werde ich über die Grenzen und Defizite der Digitalisierung im Gesundheitssystem unseres Landes sprechen und zuletzt auch ein paar Bemerkungen zum deutschen Sonderweg beim Datenschutz machen. Ich glaube, dass die beiden letzteren Punkte in direktem Zusammenhang miteinander stehen. Grenzen des ärztlichen Handelns am Lebensende Wir haben am 26.02.2020 ein Urteil des Bundesverfassungsgerichts zum ärztlich assistierten Suizid oder zur Sterbehilfe erhalten. Mein Eindruck ist, dass wir uns als Internistinnen und Internisten nicht ausreichend mit dieser Frage beschäftigen. Das Bundesverfassungsgericht hat Folgendes festgelegt: „Das allgemeine Persönlichkeitsrecht umfasst als Ausdruck persönlicher Autonomie ein Recht auf selbstbestimmtes Sterben“. Es gab Zeiten, da war Suizid strafbar, wenn er überlebt wurde. „Das Recht auf selbstbestimmtes Sterben schließt die Freiheit ein, sich das Leben zu nehmen. Die Entscheidung des Einzelnen, seinem Leben entsprechend seinem Verständnis von Lebensqualität und Sinnhaftigkeit der eigenen Existenz ein Ende zu setzen, ist im Ausgangspunkt als Akt autonomer Selbstbestimmung von Staat und Gesellschaft zu respektieren. Die Freiheit, sich das Leben zu nehmen, umfasst auch die Freiheit, hierfür bei Dritten Hilfe zu suchen, und Hilfe, soweit sie angeboten wird, in Anspruch zu nehmen“. Damit ist auch vollständig geklärt, dass jeder, der diesen Wunsch hat, Deutschland verlassen darf, um in der Schweiz, in den Niederlanden oder in Kanada den ärztlich assistierten Suizid, sofern er bei uns nicht angeboten würde, tatsächlich nachzusuchen. Mein Eindruck ist, dass zurzeit sehr viel von Juristen über diese Frage diskutiert wird, nicht aber von Medizinern außerhalb der Intensivmedizin bzw. der Palliativmedizin. Ich möchte Ihnen jetzt aufzeigen, was in anderen Ländern, die dies seit Längerem erlauben, an Veränderungen stattgefunden hat. Zuerst zeige ich Ihnen die Zahlen aus der Schweiz. In der Schweiz ist ärztlich assistierter Suizid gesetzlich erlaubt. Seit 2016 wird er statistisch erfasst, und es werden jährlich etwa 928 Fälle registriert. Zählt man die Ausländer mit, überwiegend Deutsche, die dazu in die Schweiz einreisen, dann sind es noch etwa 100 mehr. Das entspricht etwa 1,4 % der Todesfälle, die in der Schweiz jährlich insgesamt registriert werden. In den Niederlanden sieht es etwas anders aus. Dieses Land hat in dieser Frage auch eine längere Tradition. Dort wurden 2019 der entsprechenden Kommission 6361 Fälle von Sterbehilfe gemeldet. Das entspricht inzwischen 4,2 % aller Todesfälle in den Niederlanden, und im letzten Jahr gab es einen erneuten Anstieg von 3,8 % (Abb. 1). Ich habe für Sie die wichtigsten Einzelergebnisse aus dieser Statistik zusammengestellt. Es sind meistens ältere Menschen, zwischen 70 und 80 Jahren, die um einen ärztlich assistierten Suizid nachsuchen. Aber es gibt auch 40- bis 50-Jährige in signifikanter Zahl, die den Zeitpunkt ihres Todes mit ärztlicher Begleitung selbst wählen möchten. Die weit überwiegende Mehrzahl dieser Menschen begeht zu Hause und in hausärztlicher Begleitung assistierten Suizid (Abb. 2). Der überwiegende Teil der Menschen, die diesen Schritt wählen, leidet an Krebserkrankungen. Im Unterschied zu anderen Ländern besteht in den Niederlanden ebenso wie in Kanada nicht nur die Möglichkeit zum ärztlich assistierten Suizid, also der Hilfe zur Selbstmedikation der tötenden Medikamente, sondern es gibt auch die Möglichkeit des Tötens auf Verlangen. Das heißt, der Arzt führt die Infusion, die zum Tode führt, selbst aus und verlässt nicht den Raum, nachdem die Infusion angelegt wurde. Diese Form der ärztlichen Begleitung in den Tod betrifft mit 6092 fast alle Fälle von Sterbehilfe in den Niederlanden. Als Nächstes fasse ich die Situation in Kanada zusammen. Dort nennt sich der Vorgang Medical Assistance in Dying (MAID). Im Zeitraum von 2016 bis 2019 war MAID bei 2 % der Todesfälle Todesursache. Zu 65 % wird MAID von Hausärzten durchgeführt, deutlich seltener von Palliativmedizinern und noch seltener von Anästhesisten. Daneben werden auch Internisten aus Krankenhäusern hinzugezogen, und bei 7,1 % der Patienten wird MAID von Krankenpflegekräften, „nurse practitioners“, die dafür in Kanada lizensiert sind, durchgeführt. Die Schlussfolgerung aus den Daten und Fakten, die ich Ihnen hier zusammengestellt habe, sind Folgende: Ärztlich assistierter Suizid ist in Deutschland erlaubt. Auch unsere Bundesärztekammer hat ihre Regularien im Sinne des Urteils verändert. Auch das Berufsrecht der Ärzte schließt die Möglichkeit dazu ein oder zumindest das Verbot eines ärztlich assistierten Suizids aus. Die meisten ärztlich assistierten Suizide in anderen Ländern werden von Hausärzten begleitet und erfolgen in der häuslichen Umgebung. Somit ist dies dort kein Thema für den Krankenhaussektor, es ist ein Thema für den hausärztlichen ambulanten Sektor, und ich möchte unseren hausärztlich tätigen Internisten ans Herz legen, sich mit dieser Frage auseinanderzusetzen. Der zweite Punkt ist: Über 90 % der Patienten, die um einen ärztlich assistierten Suizid nachsuchen, wurden vorher ausreichend und kompetent palliativmedizinisch behandelt. Wenn Sie dann noch diejenigen dazu rechnen, denen eine palliativmedizinische Behandlung angeboten wurde, und die diese abgelehnt haben, sind es 99 %. Es geht also nie um eine Konkurrenzsituation zwischen Palliativmedizin und ärztlich assistiertem Suizid, sondern die Betroffenen wurden fast ausnahmslos vorher palliativmedizinisch ausbehandelt. Kanadische Einrichtungen raten zu ärztlich durchgeführtem Suizid statt suizidaler Selbstmedikation Der dritte Punkt ist: Wenn sowohl Tötung auf Verlangen, also „clinician-administered“, als auch Sterbehilfe durch Verschreibung von Medikamenten, „self-administered“, erlaubt sind, wie in Kanada und den Beneluxländern, wird in fast 99 % der Fälle die Tötung auf Verlangen durchgeführt. Der Grund dafür ist, dass alle ärztlichen oder pflegenden Beteiligten sagen oder befürchten, dass die Betroffenen die Medikation für den Suizid, wenn sie dazu entschlossen sind, weder effektiv noch sicher selbst durchführen können und schwerwiegende Komplikationen, die dann eben nicht zum Tode führen, sondern zu schweren Behinderungen, eintreten können. Kanadische Einrichtungen raten inzwischen dringend von der Selbstmedikation zum Suizid ab und empfehlen den ärztlich durchgeführten Suizid. Das ist der Status quo. Mein Eindruck ist, dass in unserem Kreis dieses Thema am ehesten verdrängt wird, und dass sich im Moment hauptsächlich Juristen damit auseinandersetzen. Ich bin auch nicht sicher, in welcher Form es dazu eine Gesetzgebung geben wird oder überhaupt geben sollte. Aber wir müssen dieses Thema in unseren Reihen bearbeiten, uns dazu positionieren, festlegen, welche Möglichkeiten wir sehen und welche Grenzen wir ziehen wollen, weil die Anfragen der Patienten an uns herangetragen werden. Wir sollten nicht die Bedürfnisse unserer Patienten ignorieren, wie wir es bei der Präimplantationsdiagnostik jahrelang erfolgreich getan haben, sodass damals alle betroffenen Familien in die gleiche belgische Klinik gereist sind. Jetzt fahren die Patienten, die den Wunsch haben, durch ihren Arzt in den Tod begleitet zu werden, nach Holland oder in die Schweiz. Wir sollten uns damit beschäftigen, um auch für unser Land eine von uns getragene Lösung zu finden. Lektionen aus der Coronapandemie Mein zweiter Punkt sind die Lektionen aus 2 Jahren Coronapandemie und die Schlussfolgerungen, die ich persönlich daraus gezogen habe. Diese Pandemie war ein absoluter Stresstest für unser Gesundheitssystem, für unsere persönliche Belastung, auch für unsere persönliche Betroffenheit. Wir alle rechnen im Moment schon in Wellen. Man erzählt schon: „Weißt du noch, in der zweiten Welle, damals, als wir auf der Intensivstation keine ECMO mehr zur Verfügung hatten?“ „Erinnerst du dich noch an die vierte Welle, als Omikron begann?“ Wir haben inzwischen eine der größten weltweiten pandemischen Erkrankungen, an die wir uns erinnern können, selbst im Vergleich zur Grippepandemie 1918/1919. Wir wissen von 6,2 Mio. gesicherten Todesopfern mit Nachweis des Virus. Die Dunkelziffer wird um ein Vielfaches höher sein. Wir haben inzwischen eine halbe Milliarde Menschen, die nachweislich an COVID-19 erkrankt ist. Wenn man nur die Zahlen für Deutschland betrachtet, sind es, Stand Ende April 2022, immerhin schon 23 Mio. bestätigte Fälle. Die Dunkelziffer ist wahrscheinlich doppelt so hoch, und fast 140.000 Todesopfer sind zu beklagen. Das hat selbst eine Grippeepidemie in den letzten 20 Jahren nicht an Todesopfern in unserem Land gefordert. Wie haben wir darauf reagiert? Es gab in einer faszinierenden Geschwindigkeit die Möglichkeit, diese Krankheit zu verhindern: durch die RNA-basierte Impfung, die durch zwei Unternehmen konkurrierend und hocheffizient an den Start gebracht worden ist. Ich persönlich habe mit großem Enthusiasmus beobachtet, wie die Zahl der Geimpften anstieg, nachdem die Impfung im Dezember 2020 eingeführt war. Dann kam es zu Anschuldigungen gegen Lokalpolitiker, die sich vier Tage vor dem eigentlichen Impfstart oder dem Zeitpunkt, an dem sie an der Reihe gewesen wären, haben impfen lassen. Das waren die Skandale im Dezember und im Januar 2020/2021. Heute ist der Skandal ein anderer. Wir stellten nämlich plötzlich fest, dass ab Juli, August 2021 die Impfquote überhaupt nicht mehr zunimmt. Die Gesundheitspolitik hatte anfangs Sorge, dass sie nicht genug Impfstoff beschaffen könnte – und es passierte etwas völlig anderes: Ein Viertel der Bevölkerung ließ sich nicht impfen; ein Viertel der Bevölkerung lässt sich auch heute noch nicht impfen. Ab Oktober ging es dann mit den Booster-Impfungen los. Dieselben Personen, die sich zum ersten Mal haben impfen lassen, ließen sich dann auch ihre Impfung auffrischen, aber keine neuen Bürger kamen zur Impfung. In meiner eigenen Einrichtung sind wir so weit gegangen, Impfvideos in türkischer und serbokroatischer Sprache zu produzieren, um auch noch die letzten Gruppen der Impfskeptiker zu überzeugen. Auch Eckart von Hirschhausen ist in seiner Festrede darauf eingegangen: Der Prozentsatz der Geimpften wird nicht mehr weiter steigen, wenn nicht wirklich etwas Dramatisches passiert. Und ich kann Ihnen nicht beantworten, warum. In Oberbayern hat Markus Söder einmal eine Erklärung dafür angeboten: Dort, wo die Impfrate besonders niedrig sei, im Voralpenland, wäre die Esoterik besonders verbreitet; das könnte man an der rückläufigen Zahl der niedergelassenen Ärzte und der steigenden Zahl niedergelassener Heilpraktiker deutlich ablesen. Ich fand es sehr mutig, dass ein Politiker erstmals einen direkten Zusammenhang zwischen Esoterik und Heilpraktikertum hergestellt hat. Möglicherweise hat er recht. Mitarbeiter in Praxen und Kliniken müssen von der Notwenigkeit der COVID-19-Impfung überzeugt werden Wir sehen ein zweites Problem im Nord-Süd-Gefälle und im West-Ost-Gefälle der Impfbereitschaft. Eine französische Zeitung hat mir einmal ein Interview dazu abgerungen, und ich habe versucht zu erklären, dass die französische Aufklärung nur sehr unvollständig im noch von der Romantik geprägten Deutschland angekommen ist und wir möglicherweise tatsächlich noch in Mythen und Mysterien denken und deshalb Impfung als Präventionsmaßnahme nicht akzeptieren. Eine wirkliche Antwort habe ich nicht. Wir sind aber gehalten, uns wenigstens mit der Impfskepsis bei unseren Mitarbeitern zu beschäftigen – weniger den Ärzten, aber ganz sicher bei den Pflegenden – viele von ihnen lassen sich immer noch nicht impfen. Nach den Zahlen des RKI von Ende April waren es 47.000 in nur 20 deutschen Städten und noch nicht mal in einer bundesweiten Statistik. Bis zum Herbst müssen wir einen Weg finden, zumindest die Mitarbeiter in unseren Praxen und Kliniken von der Notwenigkeit der Impfung an vorderster Front zu überzeugen, weil sonst die nächste Welle unser Gesundheitssystem erneut an seine Grenze bringen wird. Ich habe noch andere Lektionen aus der Coronapandemie gelernt. Das ist der Zweifel daran, ob die Coronapneumonie mit COVID-19 eine Krankheit für Virologen oder Hygieniker ist. Wenn Sie sich erinnern, wer die Öffentlichkeit vor laufenden Fernsehkameras informiert hat, wer die Politik beraten hat, dann waren das in anderen europäischen Ländern Infektiologen, Pneumologen, ggf. Intensivmediziner und Anästhesisten. Deutschland hatte dagegen eine Sonderstellung, in dem die, die Maßnahmen gegen Corona vorgeschlagen, propagiert und vertreten haben, Virologen waren, z. T. Hygieniker. Das hat aus meiner Sicht zu gewissen Verzerrungen in unserer Wahrnehmung und unseren Reaktionen geführt. Einige dieser Virologen hatten sich nie mit so etwas wie dem Coronavirus beschäftigt. Nicht selten waren es AIDS-Spezialisten, also Experten für ein ziemlich anderes Krankheitsbild. Aber die Empfehlungen gipfelten dann in Untersuchungen wie in diesem Artikel aus Deutsches Ärzteblatt: „Covid-19 Patienten husten Viren durch chirurgische Masken und Baumwollmasken hindurch“ (Deutsches Ärzteblatt vom 07.04.2020), übrigens auch durch FFP2-Masken. Die Untersucher sind hingegangen und haben die Porengröße der Masken rasterelektronenmikroskopisch bestimmt. Das Coronavirus ist ungefähr 100 nm groß. Wenn die Poren in diesen Maske 120 nm weit waren, wurde daraus gefolgert, dass die Masken nicht schützen können. Jeder Infektiologe in Deutschland hätte gesagt: „Alle Atemschutzmasken schützen vor bakteriellen und viralen Infektionen.“ Das ist Erfahrungswissen und vielfach durch Studien belegt, weil Viren auch elektrostatisch in den Masken haften bleiben. Auf das Gegenteil wäre ein Infektiologe nicht gekommen. Und es hatte wirkliche Konsequenzen, weil die Masken lange verteufelt und abgelehnt wurden. Das Zweite sind Instrumente wie ein kontaktfreier Türöffner. Dieser geht auf eine Studie der Hygieniker zurück. Diese haben Abstriche von Türklinken gemacht, dabei Virus-RNA gefunden und daraus geschlossen „Das Händeschütteln und Türklinken sind wichtige Übertragungswege für das Coronavirus.“ Kontaktlose Türöffner kann man bis heute für 4,99 € bei Amazon erwerben. Auch der berührungsfreie Gruß und das Vermeiden des Händeschüttelns haben wir der Entdeckung von RNA-Fragmenten auf Oberflächen zu verdanken. Pneumologen und Infektiologen wären nicht primär auf die Idee gekommen, dass man durch einen RNA-Nachweis auf einer Oberfläche einen Infektionsmodus für ein Virus, das über die Atemwege und Aerosole übertragen wird, postulieren kann. In diesem Feld hat es aber eine Veränderung gegeben, und ich betrachte es als einen der größten berufspolitischen Erfolge der letzten Jahre, den der Berufsverband Deutscher Internistinnen und Internisten (BDI) und die Deutsche Gesellschaft für Innere Medizin (DGIM) gemeinsam erstritten haben, dass am Mittwoch, den 05.05.2021, der Facharzt für Innere Medizin und Infektiologie in Deutschland eingeführt worden ist. Ein Facharzt, den unsere Nachbarländer schon seit Jahren anbieten und dessen Einführung bei uns jetzt mit reichlicher Verzögerung erfolgt ist. Dies ist letztlich gelungen, weil auch die Fächer außerhalb der Inneren Medizin erkannt haben, dass man in einer Coronapandemie die Hilfe von Infektiologen in der Krankenversorgung benötigt und am Krankenbett weniger die von Fächern, die diagnostisch ausgerichtet sind. Die Zusatzweiterbildung für Infektiologie war vor einigen Jahren für Mikrobiologen, Virologen und Hygieniker geöffnet worden; Fächer, die bei der Behandlung am Krankenbett aber keine Hilfe leisten können. Das hat es am Ende leichter gemacht, mit Argumenten zu überzeugen, und somit auch in Deutschland den Internisten und Infektiologen einzuführen. Welche Werkzeuge haben wir zur Bekämpfung der Pandemie genutzt? In Deutschland, im Vergleich zu anderen Ländern, nicht sehr viele. Die großen Studien zur Behandlung von COVID-19, z. B. der RECOVERY collaborative group [3] kamen aus Großbritannien und anderen Ländern. Wir haben dazu wenig beigetragen. Eines der Werkzeuge, nicht unbedingt ein internistisches, war die PCR-Testung, die wir an all unseren Kliniken in Windeseile aufgebaut haben. Dies ist gelungen, aber durch das Testen verschwindet eine Krankheit noch nicht. Es hilft nur, die Betroffenen zu isolieren. Die wirklich wichtigen Werkzeuge waren die Fax-Maschine zum Datenaustausch zwischen Krankenhäusern und Gesundheitsämtern und die Corona-Warn-App, die von einigen als Errungenschaft gefeiert wurde. Ich selbst erinnere mich sehr schmerzhaft daran, dass 6 Mitarbeiter des LMU-Klinikums gleichzeitig versucht haben, die gesetzlich vorgeschriebenen Meldungen ans Gesundheitsamt zu übermitteln. Da das örtliche Gesundheitsamt aber nur eine Fax-Maschine für diesen Zweck vorhält und diese einen Papierstau hatte, war über Stunden keine Meldung möglich. Es gibt seit über einem Jahr ein digitales Meldeprogramm für diesen Zweck, das aber noch nicht einmal in seiner Beta-Version zur Verfügung steht. Die Corona-Warn-App halte ich für einen Misserfolg, auch wenn sie technisch gut programmiert wurde. Sie ist 41 Mio. Mal in Deutschland heruntergeladen worden. Man muss aber wissen, dass zwei Drittel der Handys, die heute im Umlauf sind, diese App nicht verwenden können, weil ihr veraltetes System die Software nicht nutzen kann. Von den Coronafällen, die identifiziert wurden, wurden nur 20 % der Erkrankten an die App gemeldet, weil man das Prinzip der Freiwilligkeit als höchste Priorität festgelegt hatte. Somit wurde nur vor jedem vierten oder fünften Erkrankungsfall tatsächlich gewarnt, ohne genaue Orts- und Zeitangabe und ohne, dass die identifizierenden Labore das Testergebnis direkt in die Corona-Warn-App eingespielt hätten, wie z. B. die erfolgten Impfungen direkt an die COV-App oder die Warn-App weitergeleitet wurden. Andere Länder haben das besser gehandhabt, und dort haben die Warnsystem auch funktioniert. Defizite in der Digitalisierung des deutschen Gesundheitswesens Das bringt uns zum Grad der Digitalisierung in Deutschland. Heyo Kroemer hat bei seinem Vortrag in der Eröffnungssitzung bereits dargestellt, dass mehr als 95 % der Informationen zwischen Einrichtungen der Krankenversorgung in Deutschland bis heute auf Papier oder per Fax ausgetauscht werden. In keinem anderen Bereich des öffentlichen Lebens wird so wenig digitale Information übermittelt. Für die Krankenhäuser wird der Grad der Digitalisierung international anhand der Klassifikationen des Electronic Medical Records Adoption Model (EMRAM) mit den Stufen von 1 bis 7 gemessen, wobei 7 nur für Krankenhäuser mit durchgängig digitalen Patientenakten vergeben wird. Solche Krankenhäuser gibt es nur in den USA, den Niederlanden und Dänemark. Zur nächsten Stufe 6 gehören nur sehr wenige Krankenhäuser in Deutschland. Bildet man den Durchschnitt, beträgt der Mittelwert in Deutschland 2,3, in Dänemark 5,4, in den USA 5,3, und auch die Türkei hat einen höheren Digitalisierungsgrad ihrer Krankenhäuser erreicht als wir. Noch bedenklicher ist die Tatsache, dass Deutschland zwischen 2016 und 2018 im Ranking im Vergleich zu anderen Ländern zurückgefallen ist und diese Länder an uns vorbeiziehen (Tab. 1). Deutschland Österreich Europa Vereinigtes Königreich Türkei Spanien Niederlande USA Dänemark Level 7 – – 0,3 – 0,1 – 5,6 6,4 – Level 6 1,2 5,6 13,4 2,9 24,2 5,1 5,6 33,8 4,2 Level 5 18,0 11,1 30,0 52,4 19,1 50,0 66,7 32,9 95,8 Level 4 5,4 – 4,9 3,8 6,5 4,5 – 10,2 – Level 3 9,0 – 5,2 – 5,9 3,2 – 12,0 – Level 2 26,9 50,0 28,8 14,3 32,3 26,3 19,4 1,8 – Level 1 1,2 5,6 6,0 9,5 5,0 1,9 2,8 1,5 – Level 0 38,3 27,8 11,4 17,1 7,0 9,0 – 1,4 – Anzahl (n) 167 18 1455 105 682 156 36 5487 24 EMRAM-Mittelwert 2,3 2,3 3,6 3,7 3,8 3,9 4,8 5,3 54 Das signalisiert, dass wir keine wirklich überzeugenden Anstrengungen unternehmen, unsere Krankenhäuser oder unser Gesundheitssystem in Bezug auf die elektronische Patientenakte tatsächlich nach vorn zu bringen. Für Deutschland ist die umfassende Digitalisierung noch immer ferne Zukunftsmusik Estland und Dänemark sind Beispiele, wie dies vorbildlich gelingt. In Dänemark werden für alle 5 Regionen des Landes alle Patienteninformationen von Haus- und Fachärzten, von allen Leistungserbringern, einschließlich Physiotherapie und Apotheke, die gesamte digitale Bildgebung und alle Laborbefunde in einer zentralen Datenbank abgelegt. Es gibt einen elektronischen Medikationsplan, einschließlich aller elektronischen Rezepte, auch aller Folgerezepte. So lässt sich über Jahre nachverfolgen, welche Medikamente verschrieben und von Apotheken ausgegeben wurden, und wann sie aus welchem Grund abgesetzt wurden. Es gibt selbstverständlich ein elektronisches Impfregister, nicht nur für COVID-19, sondern für alle Impfungen. Darüber hinaus existieren eine elektronische Patientenverfügung und der Organspendeausweis. Patienten können über dieselbe zentrale Plattform online ihre Termine beantragen, und es wird nachgehalten, wie schnell ihnen ein Termin angeboten wurde – in jedem Krankenhaus mit Echtzeitwartezeiten. Auch die Patientenbewertungen werden dort hinterlegt. Alle Bürger können sich über ihre elektronische Patientenakte für Vorsorge- und Screeningprogramme, einschließlich der Kolonkarzinomvorsorge, anmelden. Die Registrierung als Blut‑, Stamm- oder Eizellspender findet über dasselbe Portal statt und auch die Einschreibung in klinische Studien, so die Patienten dies wünschen. Alle Partner, Patienten, Ärzte, Krankenhäuser kommunizieren webbasiert über diese Plattform. So sieht ein digitales Gesundheitssystem aus. Für unser Land ist dies alles sehr ferne Zukunftsmusik, auch wegen des Widerstands aus den eigenen Reihen der Ärzteschaft. Nehmen wir nur die elektronische Gesundheitsakte, die Telematikinfrastruktur, die 10 Jahre komplett blockiert wurde. Ich hatte mir erlaubt, in einem Leitthemenbeitrag dazu Herrn Dr. Axel Brunngraber zu zitieren, der vor 11 Jahren beim Ärztetag gesagt hat: „Wir haben in den vergangenen Jahren wichtige Bollwerke geschaffen und das Projekt auf Jahre hin gestoppt. Und das werden wir auch weiter durchhalten.“ Als ich dies geschrieben habe, hat mich Kollege Brunngraber, der niedergelassener Internist in Hannover ist, kontaktiert, um seine Gründe darzulegen: „Der Kern der Telematikinfrastruktur ist nicht die Förderung ärztlicher Arbeit (und das sollte es eigentlich sein), sondern der Zugriff auf die Ergebnisse ärztlicher Arbeit. Nach einer jahrelangen aufwendigen Beta-Testung schlecht programmierter Vehikel, die eigentlich von den Krankenkassen hätten betrieben werden müssen, liegen nun keinerlei innovative, die Qualität unserer Bemühungen unterstützende Features vor. Stattdessen prägen gravierende funktionelle Defizite den Alltag des Projektes seit über zehn Jahren.“ Dies ist sicher einer der Gründe, warum wir uns als Ärzte mit der Digitalisierung so schwertun. Die Programme und Strukturen wurden nicht von uns geschaffen, sie wurden uns übergestülpt, und wir waren viel zu selten und viel zu marginal daran beteiligt. Auch die Krankenhausinformationssysteme sind für Programmierer, Abrechnungsstellen, Rechtsabteilungen und Verwalter geschrieben worden, aber nicht für unsere ärztliche Tätigkeit. Das zu ändern, erfordert einerseits eine viel größere digitale Kompetenz unter den Ärztinnen und Ärzten und andererseits politische Vorgaben vonseiten der Ärzteschaft, damit die Weiterentwicklung in unserem Sinne und im Sinne der Patienten vollzogen wird. Die DGIM hat ihre Kommission „Digitale Transformation in der Inneren Medizin“ dafür aufgerüstet und ausgezeichnet positioniert. Deutscher Sonderweg beim Datenschutz in der Medizin Das bringt mich zum letzten Punkt, dem Datenschutz und der deutschen Auslegung der DSGVO; ein Thema, das immer mehr an Brisanz gewinnt. Unternehmen mit mehr als 20 Mitarbeitern, die personenbezogene Daten verarbeiten, benötigen nach der DSGVO einen Datenschutzbeauftragten. Die 2016 von Jan Philipp Albrecht, heute Minister in Kiel, damals Europaparlamentarier, praktisch im Alleingang durchs Europaparlament gebrachte DSGVO fordert dies ein. Das Ziel war, die Bürger vor Schaden durch den Missbrauch ihrer Daten durch Google, Apple, Amazon und vielleicht sogar die Schufa zu schützen. Die gleiche DSGVO wird aber auch auf den Medizinbereich und alle Bereiche des öffentlichen Lebens angewandt. In Deutschland unterliegen 200.000 Unternehmen der DSGVO und müssen, wenn sie noch keinen haben, einen Datenschutzbeauftragten nach DSGVO ernennen. Dies vergeben 35 % der Unternehmen an externe Berater, die nicht Mitarbeiter der Firma sind. In der Summe bedeutet das, dass in Deutschland 130.000 Datenschutzbeauftragte tätig sein werden, die uns vorgeben, wie wir im Datenschutz alles richtig machen, oder kontrollieren, ob wir es richtig gemacht haben. Im Vergleich dazu: In Deutschland sind 100.000 Steuerberater und 4000 Steuerfahnder tätig. Ich unterstelle einmal, dass der Schaden, der unserem Land und jedem einzelnen Bürger durch Missbrauch im Steuerecht entsteht, den Schaden, der durch Missbrauch im Datenschutz entstanden ist, um ein Vielfaches übersteigt. Trotzdem haben wir uns als Gesellschaft und als Staat dazu entschlossen, eine viel größere regulatorische Kontrollbürokratie für den Datenschutz aufzubauen als für das Steuerrecht. Die Sanktionen sind drakonisch. Nutzt man den Bußgeldrechner, der im Internet angeboten wird, wird ein Unternehmen mit einem Jahresumsatz von 500 Mio. € – das ist ungefähr die Hälfte der deutschen Universitätsklinika – für eine Datenschutzverletzung, die nicht „formell“, sondern „materiell“ ist und die weder „leicht“, noch „mittelschwer“ sondern als „sehr schwer“ eingeschätzt wird, mit einem Bußgeld zwischen 10 Mio. und 20 Mio. € belegt. Auch das Strafmaß ist deutlich schärfer als im Steuerrecht oder bei Körperverletzung. Komplizierend kommt hinzu, dass wir unterschiedliche Regelungen in den Bundesländern haben. In Bayern gibt es beispielsweise eine Regelung, dass die Daten von Patienten zwar für Forschung genutzt werden, nicht aber das Gelände des Krankenhauses verlassen dürfen. Sie dürfen auch Forscher, die nicht Mediziner oder an der Behandlung beteiligt sind, damit beauftragen, also z. B. Epidemiologen oder Statistiker, aber nur, wenn die Daten das Krankenhausgelände nicht verlassen. Dieses Gesetz wurde geschaffen, als man noch mit Mikrofilmen oder Papierakten arbeitete. Das hat für bayerische Uniklinika gravierende Konsequenzen, weil die Firewalls in Bayern unvergleichbar höher sind als in anderen Bundesländern. Das bedeutet aber auch, dass das LMU-Klinikum des Freistaats keine Auswertung personenbezogener Patientendaten am Leibniz-Rechenzentrum des Freistaats mit seinem achtschnellsten Rechner der Welt vornehmen darf. Krankenhäuser dürfen andere Krankenhäuser zur Speicherung oder zur Auswertung ihrer Daten nutzen, aber eben kein unabhängiges Rechenzentrum und schon gar keine bayernweite Cloud. All das verbietet der Datenschutz. In Deutschland darf jedes Krankenhaus retrospektive Patientendaten anonymisiert wissenschaftlich auswerten. Aber die Daten aus verschiedenen Krankenhäusern dürfen für diesen Zweck nicht zentral zusammengeführt werden, auch das aus Datenschutzgründen. Interessant ist, dass der Datenschutz in Ländern, die unter derselben DSGVO arbeiten, wie Estland, Österreich oder Skandinavien, dies erlaubt. In diesen Ländern findet der Datenschutz pragmatische und umsetzbare Lösungen, die den schnellen Zugriff auf Gesundheitsdaten im Notfall und zum Nutzen des betroffenen Patienten ermöglicht und die Forschung mit Gesundheitsdaten nicht verhindert. In Deutschland sollen unter derselben DSGVO präventiv hypothetische Datenschutzverletzungen durch technische Blockaden verhindert werden, auch wenn diese nur mit höchster krimineller Energie möglich wären. Die Bundesregierung hat im Koalitionsvertrag ein Gesundheitsdatennutzungsgesetz und ein Registergesetz für Gesundheitsdaten angekündigt. Ich glaube, wir müssen auf die Gestaltung dieses Gesetzes Einfluss nehmen – einerseits im Interesse unserer Patienten, andererseits zum Nutzen für die medizinische Forschung. Datensparsamkeit und Fristvorgaben zur Datenvernichtung in der Medizin vergeuden wichtige Ressourcen Dazu habe ich einige Vorschläge: Der Austausch von Patientendaten zwischen Medizinern kann Menschenleben retten. Das ist vielfach belegt und nicht nur anekdotisch. Die Beweggründe und Motive sind andere als bei Google, Amazon oder der Schufa. Die deutschen Hüter der DSGVO berücksichtigen diesen Umstand nicht, sollten sie aber. Ziel des Datenschutzes in der Medizin sollte nicht sein, den Zugang zu und die Nutzung von Daten zu verhindern, sondern Patienten vor einem Schaden durch Missbrauch ihrer Daten zu schützen. Hierin liegt der Unterschied zwischen der Auslegung der DSGVO in unserem Land und in unseren europäischen Nachbarländern. Die wichtigsten Forschungsergebnisse und Behandlungsfortschritte zur Bekämpfung der Coronapandemie kamen nicht aus Deutschland. Unsere Auslegung der DSGVO ist einer der Gründe dafür. Datensparsamkeit und Fristvorgaben zur Vernichtung von medizinischen Daten sind eine gigantische Verschwendung menschlicher, wirtschaftlicher und wissenschaftlicher Ressourcen. Wir hatten 1982 in Deutschland den weltweit größten jemals aufgezeichneten Trichinose-Ausbruch in Bitburg. Dort gab es damals ein großes Volksfest, viele haben rohes Mett gegessen, und 137 Teilnehmer haben eine Trichinose entwickelt. Die einzigen Behandlungsverläufe weltweit zu einer solchen Epidemie stammen somit aus Deutschland. Alle Akten, Health Records und Unterlagen – hätte die DSGVO damals gegolten – wären 1997 komplett vernichtet worden. Wir wüssten heute nichts über den nunmehr 40-jährigen Verlauf der Erkrankung, wir wüssten nichts über die Langzeiteffektivität irgendeiner Therapie gegen Trichinose und ebenso wenig über die letztlichen Todesursachen der Patienten, wenn die Daten, wie heute vorgeschrieben, nach 15 Jahren vernichtet worden wären. Vorschläge für die Gestaltung des geplanten neuen Gesetzes könnten sein: Die Auswertung von anonymisierten Daten aus klinischen Studien und in Krankheitsregistern sollte keine persönliche und individuelle Zustimmung mehr erfordern. Die Bayerische Akademie der Wissenschaften fordert dies konkret auch für pseudonymisierte Daten, was für die Untersuchung von Krankheitsverläufen sehr viel nützlicher ist. Eine solche individuelle Zustimmung wird auch im Steuer-, im Melde-, im Verkehrs- und im Personenstandsrecht nicht gefordert. Sonst könnte der Staat keine Steuerschätzung und keine Unfallstatistik veröffentlichen. Warum sollen diese dann für anonymisierte oder pseudonymisierte Gesundheitsdaten gelten? Die Frist zur Löschung von medizinischen Daten aus klinischen Studien und Krankheitsregistern gehört abgeschafft. Langzeitbeobachtungen über Medikamentennebenwirkungen oder chronische Erkrankungen sind sonst unmöglich. Ich habe Ihnen das Beispiel der Trichinose genannt. Register müssen darüber hinaus zusammengeführt werden können, um statistische Auswertungen erst valide zu machen und mithilfe künstlicher Intelligenz überhaupt untersuchen zu können. Datenminimierung, einer der wichtigsten Grundsätze des Bundesdatenschutzbeauftragten, macht in der Medizin überhaupt keinen Sinn. Wir müssen alles, was wir an Information über unsere Patienten erhalten haben, sammeln und speichern dürfen. Nur daraus ergeben sich individuelle Schlussfolgerungen für die Behandlung des einzelnen Patienten, v. a. in Notfallsituationen, und nur daraus lassen sich Forschungszusammenhänge zwischen Gesundheitswirkungen oder schädlichen Wirkungen, z. B. von Medikamenten, ableiten. Die Datenminimierung verhindert die Aufdeckung seltener Nebenwirkungen oder bisher unbekannter Krankheitszusammenhänge. Und als letzter Punkt: Eine enge Zweckbestimmung der Datennutzung, die über die Nutzung für die Erforschung von Krankheitsursachen oder von Behandlungsergebnissen hinausgeht, darf es nicht mehr geben. Ich war fast 20 Jahre in verschiedenen Ethikkommissionen tätig, und wann immer beantragt wurde, die Daten aus einer Hypertoniestudie erneut auf Zusammenhänge mit Diabetes und Herzinsuffizienz auszuwerten, wurde dies abgelehnt, weil die ursprüngliche Patientenaufklärung diese Auswertung nicht dezidiert eingeschlossen hatte. Die Zustimmungen müssen breit sein; prospektiv gesammelte Daten müssen ebenso wie Routinedaten ähnlich wie bei epidemiologischen Studien breit für die medizinische Forschung ausgewertet werden können. Schlussworte Meine Damen und Herren, zwischen Ihnen und dem Empfang der Stadt Wiesbaden steht nur noch meine letzte Folie. Ärztliches Handeln am Lebensende, Lektionen aus der Coronapandemie, Defizite in der Digitalisierung und beim deutschen Sonderweg für die Anwendung der DSGVO durch den Datenschutz in der Medizin, das waren die vier Grenzen der Medizin, bei denen ich mir die Freiheit genommen habe, sie zu Schwerpunkten zu machen und sie Ihnen mit auf den Weg zu geben. Dieses sind auch die Themen, denen unsere Fachgesellschaft im letzten Jahr – und ich hoffe auch weiterhin – eine hohe Priorität eingeräumt hat. Es ist mir eine wirklich große Ehre und ein echtes Privileg, hier heute vor Ihnen stehen zu dürfen. Ich danke Ihnen sehr herzlich für Ihre Aufmerksamkeit und Ihre Zeit. Markus M. Lerch, München Einhaltung ethischer Richtlinien Interessenkonflikt M. M. Lerch gibt an, dass kein Interessenkonflikt besteht. Für diesen Beitrag wurden vom Autor keine Studien an Menschen oder Tieren durchgeführt. Für die aufgeführten Studien gelten die jeweils dort angegebenen ethischen Richtlinien. Rede des Vorsitzenden der Deutschen Gesellschaft für Innere Medizin e. V., Professor Dr. med. Markus M. Lerch, gehalten im Rahmen der festlichen Abendveranstaltung zum 128. Kongress der Deutschen Gesellschaft für Innere Medizin, 01.05.2022, Kurhaus Wiesbaden. QR-Code scannen & Beitrag online lesen ==== Refs Literatur 1. https://www.consciencelaws.org/background/procedures/assist019.aspx. Zugegriffen: 29. Apr. 2022 2. https://fowid.de/meldung/sterbehilfe-niederlande-2011-2021. Zugegriffen: 29. Apr. 2022 3. RECOVERY Collaborative Group; Horby P, Lim WS, Emberson JR, Mafham M, Bell JL, Linsell L, Staplin N, Brightling C, Ustianowski A, Elmahi E, Prudon B, Green C, Felton T, Chadwick D, Rege K, Fegan C, Chappell LC, Faust SN, Jaki T, Jeffery K, Montgomery A, Rowan K, Juszczak E, Baillie JK, Haynes R, Landray MJ (2021) N Engl J Med 384(8):693–704. 10.1056/NEJMoa2021436 4. Stephani V Klauber J Benchmarking der Krankenhaus-IT: Deutschland im internationalen Vergleich Krankenhausreport 2019
PMC010xxxxxx/PMC10101480.txt	==== Front J Infect J Infect The Journal of Infection 0163-4453 1532-2742 The British Infection Association. Published by Elsevier Ltd. S0163-4453(23)00205-0 10.1016/j.jinf.2023.04.005 Letter to the Editor SARS-CoV-2 variant-dependent inflammasome activation Teyssou Elisa ⁎ Marot Stéphane Gothland Adélie Malet Isabelle Zafilaza Karen Leducq Valentin Cocherie Théophile Todesco Eve Soulié Cathia Marcelin Anne-Geneviève Calvez Vincent Sorbonne Université, INSERM, Institut Pierre Louis d′Epidémiologie et de Santé Publique, AP-HP, Hôpitaux Universitaires Pitié Salpêtrière – Charles Foix, Laboratoire de Virologie, F-75013 Paris, France ⁎ Corresponding author. 13 4 2023 7 2023 13 4 2023 87 1 6263 8 4 2023 © 2023 The British Infection Association. Published by Elsevier Ltd. All rights reserved. 2023 The British Infection Association Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcDear Editor, A previous study showed that expression of the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome, an innate immunity pathway, was up-regulated in cancer patients infected by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and possibly associated with the severity of the coronavirus disease 2019 (Covid-19).1 It has been shown that SARS-CoV-2 infection led to the activation of the NLRP3 inflammasome, and suggested that inflammasomes could be used as markers of the disease severity.2 Indeed, it has been observed that SARS-CoV-2 replication and infection in lung human macrophages is a critical driver of the Covid-19 disease.3 Innate immunity is the first line of defense in response to pathogens, which acts locally and also leads the stimulation of adaptive immunity through at least with Interleukin-1β (IL-1β), one of the major secreted cytokine of the NLRP3 inflammasome.4 The aim of this study was to assess and compare the level of IL-1β secretion in monocyte-like cells infected with six different SARS-CoV-2 variants of concern and possibly observed a variant-dependent pattern of inflammasome activation. Six SARS-CoV-2 variants (historical (B.1, D614G), Alpha, Beta, Gamma, Delta and Omicron BA.1) were isolated from COVID-19 molecular proven hospitalized patients by inoculation of Vero or Vero-TRMPSS2 cells. THP-1 monocyte-like, that are the most commonly used cell line for the study of inflammasome activation, were cultured with RPMI-hepes 10% FBS-0.05 mM 2-mercaptoethanol. A total of 5 × 104 of THP-1 cells was plated per well in 96-wells plate and differentiated in macrophages-like cells with 10 nM of PMA for 24 h.5 The SARS-CoV-2 infection of the differentiated THP-1 was first confirmed by RT-qPCR. The relative viral load (VL) was assessed from CT values (ORF1ab target gene) obtained by the TaqPath COVID-19 RT-PCR assay (ThermoFisher, Waltham, USA) and by linear regression in log10 copies/ml with a standard curve realized from a SARS-CoV-2 positive nasopharyngeal sample quantified by Droplet-Digital PCR (Bio-Rad). Cells were infected with the historical SARS-CoV-2 strain at an MOI of 0.1 and relative VL were measured at 4 and 24 h post infection in the supernatant. Differenciated-THP-1 were first primed with LPS 1 µg/ml for 2 h and infected with different SARS-CoV-2 variants at an MOI of 0.1. IL-1β was measured by the Lumit Human IL-1β Immunoassay in the supernatant after 24 h of infection. Results come from multiple independent experiments. We first observed an increase of the VL between 4 h and 24 h post infection which showed that the THP-1 cells are permissive to the historical SARS-CoV-2 strain ( Fig. 1A).Fig. 1 SARS-CoV-2 variants-dependent IL-1β secretion in macrophage-like THP-1 cells. A) Supernatant relative viral load of differentiated-THP-1 cells infected by the SARS-CoV-2 historical strain after 4 and 24 h post infection at an MOI of 0.1 indicative of a permissive infection. B) Histograms represent IL-1β quantification in supernatants of non- (mock) or SARS-CoV-2 infected cells. Nigericin is used as positive control for NLRP-3 activation in differentiated-THP-1 cells. p < 0.05; ***p < 0.0001. Data shown result from multiple independent experiments. Fig. 1 We next compared IL-1β secretion induced by the 6 SARS-CoV-2 sublineages after infection of macrophages-like THP-1. We observed that THP-1 cells infected with SARS-CoV-2 variants presented a significantly higher IL-1β secretion than non-infected cells (Fig. 1B) and that some SARS-CoV-2 variants led to a stronger IL-1β secretion. We observed a significantly higher level of IL-1β cells infected with Omicron BA.1 sublineage compared to other tested variants, in particular. Indeed, Omicron BA.1 infected cells presented the higher IL-1β secretion (median 385.7 pg/ml IQR [302.6–426.3]) follows by the Delta and the historical variants (median 303.6 [266.3–391.9] and 281.9 [207.2–410], respectively). Alpha, Beta and Gamma variants presented the lowest IL-1β secretion (median 228.1 [192.5–276.4], 219.1 [185.1–354.2] and 211 [149.8–228.8]) (Fig. 1B). Our results showed, as expected, that inflammasome activation is induced by all the 6 SARS-CoV-2 sublineages. However, a variation in the level of IL-1β secretion was observed between the variants. Hence, our results shown that Omicron BA.1 sublineage lead to a higher IL-1β secretion, which could possibly activate adaptative T cell immunity faster. Our results therefore suggested that Omicron BA.1 was more sensed by the innate immune cells or was less prone to counteract inflammasome activation than the other variants. This higher activation of the inflammasome pathway could lead to a viral neutralization with a better efficiency, and associated to the upper respiratory tract tropism of the Omicron BA.1, could possibly explain its less clinical virulence. Indeed, several studies have shown that Omicron BA.1 sublineage present a stronger tropism for the upper airway cells with a less efficient replication in the lung cells than others SARS-CoV-2 variants.6, 7 Even with a higher response of IL-1β secretion, Omicron infection probably not led to a cytokine storm in the lung, which is associated with a poor prognosis, due to its upper respiratory tract preferential localization. Pyroptosis, the pore-forming inflammatory cell death pathway triggered by NRLP3 inflammasome was observed in SARS-CoV-2 infection and known to contribute to Covid-19 pathology.8 It would be interesting to further our study and explore if a variant-dependent modulation of this cell death pathway could be observed. Taking together, these results suggest that the innate immune response and precisely, IL-1β secretion pathways were induced in a SARS-CoV-2 variant-dependent manner. Declaration of Competing Interest The authors declare that they have no conflict of interest. Acknowledgments The authors acknowledged all the members of the Pitié-Salpêtrière, for their implication in the SARS-CoV-2 patient care. We thank the ANRS-MIE (Agence Nationale de Recherches sur le SIDA et les hépatites virales-Maladies Infectieuses Emergentes) (AC43, Medical Virology) and the Emergen Consortium for their support and funding. ==== Refs References 1 Cui Haoran Liu Jiaxin Zhang Leiliang The high expression of key components of inflammasome and pyroptosis might lead to severe COVID‐19 infection in cancer patients J Infect 84 4 2022 e19 e21 10.1016/j.jinf.2022.01.043 2 Rodrigues Tamara S. de Sá Keyla S.G. Ishimoto Adriene Y. Amanda Becerra Samuel Oliveira Leticia Almeida Inflammasomes are activated in response to SARS-CoV-2 infection and are associated with COVID-19 severity in patients J Exp Med 218 3 2021 e20201707 10.1084/jem.20201707 3 Sefik Esen Qu Rihao Junqueira Caroline Kaffe Eleanna Mirza Haris Zhao Jun Inflammasome activation in infected macrophages drives COVID-19 pathology Nature 606 7914 2022 585 593 10.1038/s41586-022-04802-1 35483404 4 Van Den Eeckhout Bram Tavernier Jan Gerlo Sarah Interleukin-1 as innate mediator of T cell immunity Front Immunol 11 2021 621931 10.3389/fimmu.2020.621931 5 The choice of phorbol 12-myristate 13-acetate differentiation protocol influences the response of THP-1 macrophages to a pro-inflammatory stimulus. Elsevier Enhanced Reader〉; n.d. DOI: 〈10.1016/j.jim.2016.01.012. 6 Nori Wassan Ghani Zghair Muna Abdul Omicron targets upper airways in pediatrics, elderly and unvaccinated population World J Clin Cases 10 32 2022 12062 12065 10.12998/wjcc.v10.i32.12062 36405264 7 Meng Bo Abdullahi Adam Ferreira Isabella A.T.M. Goonawardane Niluka Saito Akatsuki Kimura Izumi Altered TMPRSS2 usage by SARS-CoV-2 Omicron impacts infectivity and fusogenicity Nature 603 7902 2022 706 714 10.1038/s41586-022-04474-x 35104837 8 Bittner Zsofia Agnes Schrader Markus George Shilpa Elizabeth Amann Ralf Pyroptosis and its role in SARS-CoV-2 infection Cells 11 10 2022 1717 10.3390/cells11101717 35626754
PMC010xxxxxx/PMC10102536.txt	==== Front J Infect J Infect The Journal of Infection 0163-4453 1532-2742 The British Infection Association. Published by Elsevier Ltd. S0163-4453(23)00203-7 10.1016/j.jinf.2023.04.003 Letter to the Editor Cellular immunity against SARS-CoV-2 depends on the serological status Pighi Laura Section of Clinical Biochemistry, University of Verona, Verona, Italy Service of Laboratory Medicine, Pederzoli Hospital, Peschiera del Garda, Italy Henry Brandon M. Clinical Laboratory, Division of Nephrology and Hypertension, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA De Nitto Simone Salvagno Gian Luca Section of Clinical Biochemistry, University of Verona, Verona, Italy Service of Laboratory Medicine, Pederzoli Hospital, Peschiera del Garda, Italy Lippi Giuseppe * Section of Clinical Biochemistry, University of Verona, Verona, Italy * Correspondence to: Section of Clinical Biochemistry, University Hospital of Verona, Piazzale L.A. Scuro, 10, 37134 Verona, Italy. 14 4 2023 7 2023 14 4 2023 87 1 5758 5 4 2023 © 2023 The British Infection Association. Published by Elsevier Ltd. All rights reserved. 2023 The British Infection Association Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Abbreviations SARS-CoV-2 severe acute respiratory syndrome coronavirus 2 COVID-19 coronavirus disease 2019 IFN-γ interferon-gamma IGRA interferon-gamma release assay (IGRA) ==== Body pmcDear Editor, Cellular and humoral immunity against severe acute respiratory syndrome coronavirus (SARS-CoV-2), either naturally acquired or vaccine-elicited, are both essential for limiting acute infections and preventing unfavorable outcomes in those who develop coronavirus disease 2019 (COVID-19).1 Recent data, like those published by Bonnet et al.,2 show that the cellular immunity measured with an interferon-gamma (IFN-γ) release assay (IGRA) displays a progressive decline 6 months after full vaccination with various COVID-19 vaccines, but persists at higher values in those with prior SARS-CoV-2 infection. This study was hence planned to better elucidate the 1-year kinetics of cellular immunity in recipients of COVID-19 vaccine, with or without incident SARS-CoV-2 infection. We enrolled a cohort of ostensibly healthy healthcare workers of the Pederzoli Hospital in Peschiera del Garda (Verona) who had previously received a complete primary vaccination cycle and a single homologous booster with the monovalent Pfizer/BioNTech mRNA BNT162b2 vaccine (Comirnaty, Pfizer Inc, NY, USA). Patients were recruited on voluntary basis between November-December 2022, before receiving a second booster with the new bivalent formulation (Comirnaty, Pfizer Inc, NY, USA) nearly 1 year after the last vaccine dose. Blood was drawn before bivalent vaccine administration. Cellular immunity was assayed with Elecsys IGRA SARS-CoV-2 test (Roche Diagnostics, Basel, Switzerland), as comprehensively described elsewhere.3 Serostatus, reflecting immunological memory and incident SARS-CoV-2 infection between the two vaccine boosters, was measured with anti-SARS-CoV-2 antibodies (MAGLUMI 2019-nCoV lgG CLIA; SNIBE, Shenzhen, China). This test detects the presence of IgG antibodies directed against both SARS-CoV-2 S and N proteins, the latter not included into the BNT162b2 vaccine earlier administered. Serum values ≥ 1.1 IU/mL are reactive.4 Test results, expressed as median and interquartile range (IQR), were analyzed with Mann-Whitney U test and multivariate analysis (multiple linear regression analysis), using Analyse-it (Analyse-it Software Ltd, Leeds, UK). All subjects recruited in this prospective observational study provided written informed consents for participation. The study was conducted in accordance with the Declaration of Helsinki and the protocol was approved by the Ethics Committee of Verona and Rovigo Provinces (59COVIDCESC; November 8, 2021). The final study population consisted of 74 subjects (55% female) recruited before BNT162b2 bivalent vaccination (median age 45 years; IQR: 35–53 years)The median time passed since the last vaccination (i.e., the first vaccine booster) was 12 months (IQR, 12–13 months). Overall, 35 subjects had anti-SARS-CoV-2 N/S IgG antibodies below the 1.1 cutoff value (0.3 AU/mL; IQR 0.0–0.7 AU/mL), whilst 39 had serum values above such cutoff (6.6 AU/mL; IQR, 3.7–14.5 AU/mL), respectively. As shown in Fig. 1, the median IGRA value was significantly higher in seropositive (0.66 IU/mL; IQR, 0.21–1.32 IU/mL) than in seronegative subjects (0.36 IU/mL; IQR; 0.10–0.79 IU/mL; p < 0.001). Sex (p = 0.514), age (p = 0.465) and time since the last vaccine dose (p = 0.057) were similar between these two cohorts. In multivariable analysis, anti-SARS-CoV-2 N/S IgG seropositivity (p = 0.001), but not sex (p = 0.946), age (p = 0.622) or time since the last vaccine dose (p = 0.772), significantly predicted IGRA values.Fig. 1 IGRA SARS-CoV-2 values in ostensibly healthy healthcare workers stratified according to anti-SARS-CoV-2N/S IgG serostatus. SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; IGRA, interferon gamma release assay. Fig. 1 Taken together, the results of our study suggest that the SARS-CoV-2 serostatus may be a significant and independent predictor of cellular immunity. In particular, subjects with anti-SARS-CoV-2N/S IgG antibodies above the cutoff of the assay, likely reflecting an incident infection after the last vaccine dose, are more likely to present a sustained cellular immunity and, therefore, likely better protection against the risk of severe COVID-19 illness.5 Finally, given that serologic assays are more widely available, have a faster turnaround time and a higher throughput compared to IGRA, the ability of serostatus to potentially predict cellular immunity may be a useful tool in identifying vulnerable patients requiring boosters for protection against severe disease and thus should be further evaluated in future studies. Funding The authors received no funding for this work. Ethical approval Research involving human subjects complied with all relevant national regulations, institutional policies and was performed in accordance with the tenets of the Helsinki Declaration (as revised in 2013), and has been approved by the Ethics Committee of the Provinces of Verona and Rovigo (59COVIDCESC; November 8, 2021). CRediT authorship contribution statement B.M.H., G.L.S. and G.L. planned the research; L.P, and S.D.N. performed the enrollment of participants and managed the study; G.L analyzed the data and realized the statistic tests; G.L. wrote the paper. All authors have accepted responsibility for the entire content of this manuscript and approved its submission. Declaration of Competing Interest Authors state no conflict of interest. Acknowledgments None. ==== Refs References 1 Diani S. Leonardi E. Cavezzi A. Ferrari S. Iacono O. Limoli A. SARS-CoV-2-the role of natural immunity: a narrative review J Clin Med 11 2022 6272 36362500 2 Bonnet B. Chabrolles H. Archimbaud C. Brebion A. Godignon M. Dutheil F. Comparative T and B immune responses of four different anti-COVID-19 vaccine strategies 6 months after vaccination J Infect 84 2022 e45 e47 35278482 3 Salvagno G.L. Pighi L. Henry B.M. Valentini M. Tonin B. Bragantini D. Assessment of humoral and cellular immunity after bivalent BNT162b2 vaccination and potential association with reactogenicity Clin Chem Lab Med 2023 10.1515/cclm-2023-0055 4 Lippi G. Henry B.M. Pighi L. De Nitto S. Salvagno G.L. Are anti-SARS-CoV-2 S/N IgG/IgM antibodies always predictive of previous SARS-CoV-2 infection? Adv Lab Med 2023 10.1515/almed-2023-0008 (Epub ahead of print) 5 Lippi G. Mattiuzzi C. Henry B.M. Is cellular immunity the future key for deciphering and monitoring COVID-19 vaccines efficacy? J Lab Precis Med 7 2022 1
PMC010xxxxxx/PMC10103036.txt	==== Front Food Environ Virol Food Environ Virol Food and Environmental Virology 1867-0334 1867-0342 Springer US New York 37058225 9553 10.1007/s12560-023-09553-4 Research Genotype Diversity of Enteric Viruses in Wastewater Amid the COVID-19 Pandemic Hoque Sheikh Ariful 12 Kotaki Tomohiro 3 Pham Ngan Thi Kim 1 Onda Yuko 1 Okitsu Shoko 1 Sato Shintaro 34 Yuki Yoshikazu 5 Kobayashi Takeshi 3 Maneekarn Niwat 6 Kiyono Hiroshi 578 Hayakawa Satoshi 1 Ushijima Hiroshi [email protected] 1 1 grid.260969.2 0000 0001 2149 8846 Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, 30-1 OyaguchiKamicho, Itabashi-Ku, Tokyo, 173-8610 Japan 2 grid.8198.8 0000 0001 1498 6059 Cell and Tissue Culture Laboratory, Centre for Advanced Research in Sciences (CARS), University of Dhaka, Dhaka, 1000 Bangladesh 3 grid.136593.b 0000 0004 0373 3971 Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 565-0871 Japan 4 grid.412857.d 0000 0004 1763 1087 Department of Microbiology and Immunology, School of Pharmaceutical Sciences, Wakayama Medical University, Wakayama, 640-8156 Japan 5 grid.411321.4 0000 0004 0632 2959 Department of Human Mucosal Vaccinology, Chiba University Hospital, Chiba, Japan 6 grid.7132.7 0000 0000 9039 7662 Department of Microbiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand 7 grid.136304.3 0000 0004 0370 1101 Research Institute of Disaster Medicine, Institute for Global Prominent Research, Institute for Advanced Academic Research, Chiba University, Chiba, Japan 8 grid.266100.3 0000 0001 2107 4242 CU-UCSD Center for Mucosal Immunology, Allergy and Vaccines (cMAV), Division of Gastroenterology, Department of Medicine, University of California, San Diego, USA 14 4 2023 2023 15 2 176191 27 12 2022 15 3 2023 © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Viruses remain the leading cause of acute gastroenteritis (AGE) worldwide. Recently, we reported the abundance of AGE viruses in raw sewage water (SW) during the COVID-19 pandemic, when viral AGE patients decreased dramatically in clinics. Since clinical samples were not reflecting the actual state, it remained important to determine the circulating strains in the SW for preparedness against impending outbreaks. Raw SW was collected from a sewage treatment plant in Japan from August 2018 to March 2022, concentrated by polyethylene-glycol-precipitation method, and investigated for major gastroenteritis viruses by RT-PCR. Genotypes and evolutionary relationships were evaluated through sequence-based analyses. Major AGE viruses like rotavirus A (RVA), norovirus (NoV) GI and GII, and astrovirus (AstV) increased sharply (10–20%) in SW during the COVID-19 pandemic, though some AGE viruses like sapovirus (SV), adenovirus (AdV), and enterovirus (EV) decreased slightly (3–10%). The prevalence remained top in the winter. Importantly, several strains, including G1 and G3 of RVA, GI.1 and GII.2 of NoV, GI.1 of SV, MLB1 of AstV, and F41 of AdV, either emerged or increased amid the pandemic, suggesting that the normal phenomenon of genotype changing remained active over this time. This study crucially presents the molecular characteristics of circulating AGE viruses, explaining the importance of SW investigation during the pandemic when a clinical investigation may not produce the complete scenario. Keywords COVID-19 pandemic Enteric viruses Genotypes Raw sewage issue-copyright-statement© Springer Science+Business Media, LLC, part of Springer Nature 2023 ==== Body pmcIntroduction Acute gastroenteritis (AGE) remains a major global health problem: causing significant morbidity and mortality, though mainly in developing countries, it poses a substantial economic burden in both developing and developed countries around the world (Chow et al., 2010; Hoque et al., 2019a, 2019b). Viruses including rotavirus (RV), norovirus (NoV), adenovirus (AdV), astrovirus (AstV), sapovirus (SV), and enteroviruses (EV) remain the leading causes of AGE, particularly, in children which represent about 70% of total AGE (Chow et al., 2010; Maria & Hrishikesh, 2018). Being a developed and industrialized nation, Japan still struggles against AGE-associated morbidity and economic losses throughout the year (Kawata et al., 2020). To prevent severe RV infections, Japan has introduced RV vaccines as voluntary vaccines since 2011 and included these in the national immunization program from October 2020, yet the diversity in RV genotypes and increasing trends of other diarrheal viruses have been found in post-RV-vaccination era worldwide including Japan (Gikonyo et al., 2020; Hoque et al., 2022a, 2022b, 2022c; Tsugawa et al., 2021). However, after the emergence of the pandemic coronavirus disease-2019 (COVID-19), the implementation of non-pharmaceutical interventions (NPIs) like social distancing, mask-wearing, increased hand hygiene, school closures, and working from home have proven effective to reduce COVID-19 along with many other infectious diseases including AGE (Eigner et al., 2021; Zhang et al., 2022). It was thought that the precautious lifestyle adopted during the COVID-19 pandemic may have decreased viral AGE. However, more recently, we detected an abundance of diarrheal viruses in raw sewage during the COVID-19 pandemic, suggesting that infections in the population may not have decreased with the introduction of NPIs (Hoque et al., 2022a, 2022b, 2022c). The number of cases declined, likely due to reduced transmission because of school closures, activity restrictions, as well as patients’ disinterest in seeking medical care during the pandemic, resulting in fewer reports (Armistead et al., 2022). Since the infections are widespread in the community, there is a constant risk that a new outbreak strain may emerge in a short time. Therefore, it remains urgent to investigate the circulating strains in the wastewater, exceptionally, when clinical samples are no more efficient to provide the complete scenario of the infections. In fact, wastewater-based epidemiology (WBE), filling the gap of individual testing, provides an early warning of the emergence of infectious agents in the community and its subsequent progression toward an outbreak. WBE is especially important for AGE viruses, as diarrhea is usually caused by contaminated food and/or water that may be adulterated from the environment (Hafliger et al., 2000; Laine et al., 2011). Again, enteric viruses may remain asymptomatic (Okitsu et al., 2020), which could be missed in clinical diagnosis but identified by WBE. In this study, we collected raw sewage water (SW) regularly from a wastewater treatment plant in Japan well before the pandemic and examined the molecular characteristics of circulating strains of the major diarrheal viruses before and after the emergence of the COVID-19 pandemic, which remain critical for understanding the evolutionary relationship among genotypes during the pandemic. Materials and Methods Design of the Study A total of 39 raw SWs collected almost monthly from August 2018 to March 2022 from a sewage treatment plant in the Kansai region of Japan were concentrated and analyzed for the presence of group A RV (RVA), NoV GI, NoV GII, AdV, AstV, SV, EV, and in addition nCoV (novel coronavirus 2019) after detection of spiked internal control murine norovirus (MNV) by reverse transcription-polymerase chain reaction (RT-PCR). In Japan, although the first COVID-19 case was identified on January 14, 2020, a series of containment measures, including suspension of large gatherings, campaigning for hygiene, and nationwide school closures were implemented from early March 2020 (Imai et al., 2022). Thus, 16 samples collected from August 2018 to February 2020 were considered pre-restriction samples, while the remaining 23 samples were collected thereafter during the restriction period of COVID-19. Sewage Water (SW) Collection and Concentration About half-liter of the inlet raw SW was collected in a clean PET bottle and kept frozen until further processing for concentration. About 50 ml of raw SW was first mixed with MNV as internal process control and centrifuged at 3000 rpm (RCF 1000×g) for 10 min to remove large particles from the supernatant. The clear supernatant was then mixed with 4 g of polyethylene glycol (PEG)-6000 (Kanto Chemical Co., Inc., Tokyo, Japan) and 1.2 g of NaCl (Sigma Aldrich, St. Louis, MO) and stirred at room temperature for 4 h. The suspension was then centrifuged at 10,000 rpm (RCF 11,900×g) for 30 min and the supernatant was discarded without disturbing the pellet. Finally, the pellet was suspended in 0.5 ml of nuclease-free water (QIAGEN, Hilden, Germany), aliquoted at 200 µl/tube for storage at − 30 °C. Extraction of Viral RNA and Reverse Transcription (RT) Viral RNA was extracted from 140 µl of concentrated SW using QIAamp Viral RNA mini kit (QIAGEN) following the manufacturer’s instructions and stored at − 30 °C until use. For cDNA synthesis, 5 µl of RNA was mixed with 0.5 µl of 50% DMSO and denatured at 95 °C for 5 min, followed by immediate cooling on ice. The RT was performed using ReverTra Ace reverse transcriptase (Toyobo, Osaka, Japan) and random primers (Takara, Shiga, Japan) through a single thermal cycle of 30 °C for 10 min, followed by 42 °C for 40 min, and 95 °C for 5 min before cooling or storage at − 30 °C. Detection of Viruses and Molecular Analyses Target viruses were detected after the RT by monoplex polymerase chain reaction (PCR) using GoTaq Green Master mixes (Promega, Madison, WI) and specific primers as described previously (Thongprachum et al., 2018). Namely, the partial regions of VP7 of RVA (primer pair: sBeg9-VP7-1’), capsid of NoV GI (G1SKF-G1SKR), GII (1st PCR: COG2F-G2SKR, nested PCR: G2SKF-G2SKR) and SV (SLV5317-SLV5749), hexon of AdV (Ad1-Ad2), ORF-1b of AstV (SF0073-SF0076), and 5’UTR of EV (F1-R1) were amplified and sequenced for screening and genotyping, respectively (Thongprachum et al., 2018). The MNV was confirmed by a nested RT-PCR (Kitajima et al., 2009). The PCR was maintained: initial denaturation at 94 °C for 3 min, followed by 37 cycles of denaturation, annealing, and elongation, each for 1 min at 94 °C, 50 °C, and 72 °C, respectively, and the final extension at 72 °C for 7 min. The first PCR product (1 μl) was re-amplified using the same specific primers if the first PCR remained negative or faint. In addition, RV-vaccine strain-specific RT-qPCR was done to assess Rotarix (NSP2 gene) and RotaTeq (VP6 gene) strains in all RVA-positive samples as described previously (Gautam et al., 2014; Hoque et al., 2022a, 2022b, 2022c). To detect nCoV, both nested and real-time RT-PCRs were performed using primer sets of ORF1a (Shirato et al., 2020) and CDC 2019-nCoV_N2 (Kitamura et al., 2021), respectively. PCR amplicons were purified and sequenced through the Sanger sequencing method. The sequences were analyzed using the Chromas (ver 2.6.6) and Bioedit Sequence Alignment Editor (ver 7.2.6.1). The genotypes were determined by the identity (nucleotide identity) with reference sequences obtained from the NCBI GenBank database (https://blast.ncbi.nlm.nih.gov/Blast.cgi). In addition, the major G-genotypes including G1, G2, human typical G3, equine-like G3 (G3e), G4, G8, G9, and G12 were determined in RVA-positive samples by nested PCR using primers as described by Fujii et al., (2019) with some modifications: the 1st PCR products were 30-fold diluted and 1 μl of it was used in 2nd monoplex PCR ran for 30 cycles. The final multiple sequence alignments and the construction of the phylogenetic trees were performed using MEGA7 software using the Neighbor-Joining method with the Kimura 2-parameter model and statistical significance testing by 1000 bootstrapping replicates. Nucleotide Accession Number A total of 76 nucleotide sequences determined in this study were deposited in the GenBank database for the accession numbers: RVA (OP696914-OP696931), NoV GI (OP692718-OP692724), NoV GII (OP692737- OP692751), SV (OP696906-OP696913), AdV (OP696942-OP696949), AstV (OP696932-OP696941), and EV (OP696950-OP696959). Results An Abundance of Enteric Viruses Before and After the Emergence of Pandemic Among the 16 pre-restriction samples, SV was detected in 81.2% (13 of 16) of the samples, whereas other viruses were detected in nearly 50% (7 or 8 of 16) of the samples (Table 1). In contrast, RVA, NoV GI, and SV were positively detected in about 70% (16 of 23) of samples, followed by 65.2% AstV, 61% NoV GII, 47.8% EV, and 43.5% AdV among 23 samples collected during the restriction period of COVID-19 from March 2020 to March 2022.Table 1 Distribution of genotypes before and after restriction activities in COVID-19 pandemic Total positives Before (Aug’18-Feb’20) (n = 16) After (Mar’20-Mar’22) (n = 23) RVA 61.5% (24 of 39) 50% (8 of 16) G1 (8.3%), G2 (8.3%), G3 (20.8%), G3e (8.3%), G8 (12.5%), G9 (12.5%), G11 (4.2%), and undetected (4.2%) 69.6% (16 of 23) G1 (25%), G2 (16.7%), G3 (50%), G3e (37.5%), G6 (4.2%), G8 (33.3%), G9 (37.5%), G10 (4.2%), and undetected (12.5%) NGI 59% (23 of 39) 43.7% (7 of 16) GI.3 (4.3%), and undetected (26.1%) 69.6% (16 of 23) GI.1 (8.7%), GI.3 (13%), GI.6 (4.3%), and undetected (43.5%) NGII 56.4% (22 of 39) 50% (8 of 16) GII.1 (4.5%), GII.2 (4.5%), GII.17 (4.5%), and undetected (22.7%) 60.9% (14 of 23) GII.2 (40.9%), GII.6 (4.5%), GII.17 (9.1%), and undetected (9.1%) SV 74.4% (29 of 39) 81.2% (13 of 16) GI.2 (3.4%), GII.3 (10.3%), and undetected (31%) 69.6% (16 of 23) GI.1 (10.3%), GI.2 (3.4%), and undetected (41.4%) AdV 46.1% (18 of 39) 50% (8 of 16) F41 (27.8%), and undetected (16.7%) 43.5% (10 of 23) F41 (16.7%), and undetected (38.9%) AstV 59% (23 of 39) 50% (8 of 16) MLB1 (8.7%), MLB3 (4.3%), and undetected (21.7%) 65.2% (15 of 23) MLB1 (8.7%), CAstV (21.7%), and undetected (34.8%) EV 48.7% (19 of 39) 50% (8 of 16) CV-A2 (5.3%), CV-A10 (5.3%), CV-A16 (5.3%), CV-A24 (5.3%), CV-B4 (5.3%), E11 (5.3%), and undetected (10.5%) 47.8% (11 of 23) CV-A4 (5.3%), CV-A6 (5.3%), CV-A19 (5.3%), E30 (5.3%), and undetected (36.8%) % among positives. Since RVA genotypes were investigated by nested RT-PCR, multiple genotypes were detected in RVA but not in other viruses The average detection rates in the pre- (53.6%) and post-restriction (61%) periods did not differ significantly (P = 0.26 of t-test), suggesting that AGE did not decrease in the community during the pandemic. However, nCoV was not detected in any of these samples. Seasonal Distributions Although these viruses remain abundant in all four seasons found in Japan including the spring (March to May), summer (June to August), autumn (September to November), and winter (December to February), the average detection rate remained highest in the winter (74.6%), followed by spring (61.4%), autumn (52.3%), and summer (42.8%) (Table 2). Namely, except EV, all other six diarrheal viruses were detected most frequently in the winter and lowest in the summer, while EV was detected vice versa (Table 2). Seasonal distribution of these viruses appeared similar before and after the pandemic (Table 2).Table 2 Seasonal distribution of major AGE viruses in raw SW Seasons Year* Sample No./season RVA NGI NGII SV AdV AstV EV Total Summer (Jun–Aug) 2018 1 1(100) 0(0) 0(0) 1(100) 1(100) 1(100) 1(100) 24 of 56 (42.8)* 2019 3 0(0) 0(0) 2(66.6) 2(66.6) 0(0) 0(0) 2(66.6) 2020 2 1(50) 1(50) 0(0) 2(100) 1(50) 0(0) 1(50) 2021 2 1(50) 2(100) 1(50) 1(50) 0(0) 2(100) 1(50) Autumn (Sep–Nov) 2018 3 0(0) 2(66.6) 0(0) 2(66.6) 1(33.3) 1(33.3) 2(66.6) 44 of 84 (52.3) 2019 3 3(100) 0(0) 3(100) 2(66.6) 3(100) 2(66.6) 2(66.6) 2020 3 2(66.6) 1(33.3) 1(33.3) 1(33.3) 1(33.3) 0(0) 1(33.3) 2021 3 1(33.3) 1(33.3) 3(100) 2(66.6) 2(66.6) 3(100) 2(66.6) Winter (Dec–Feb) 2018 0 – – – – – – – 47 of 63 (74.6) 2019 3 2(66.6) 3(100) 2(66.6) 3(100) 3(100) 2(66.6) 0(0) 2020 3 3(100) 3(100) 2(66.6) 2(66.6) 1(33.3) 2(66.6) 1(33.3) 2021 3 2(66.6) 3(100) 3(100) 3(100) 3(100) 3(100) 1(33.3) Spring (Mar–May) 2018 0 – – – – – – – 43 of 70 (61.4) 2019 3 2(66.6) 2(66.6) 2(66.6) 3(100) 0(0) 2(66.6) 1(33.3) 2020 3 2(66.6) 2(66.6) 0(0) 2(66.6) 1(33.3) 1(33.3) 2(66.6) 2021 3 3(100) 2(66.6) 3(100) 2(66.6) 0(0) 3(100) 2(66.6) 2022 1 1(100) 1(100) 1(100) 1(100) 1(100) 1(100) 0(0) Pandemic seasons have been covered by bold Number of positives (% among sample number in that season) **Total positives of total samples for 7 viruses (%) Genotype Diversity of RVA As shown in Table 1, all major genotypes of RVA including G1, G2, G3, G3e, G8, and G9 increased sharply during the pandemic. The most common genotype was G3 (85%), followed by G3e, G8, G9 (each remained 55%), G1 (40%), G2 (30%), and G6, G10, G11 (each remained 5%) over the study period. Since RVAs are found in both humans and animals, we did a sequence analysis of the VP7 gene to differentiate the animal strains and human strains of RVAs. Phylogenetic analysis of RVA revealed that this raw sewage contained RVA from both human and animal sources: R41, R48, R50, R51, and R60 strains remained genetically close (93–100% identity) to animal strains, while R40, R49, R52, R61, and R63 exhibited almost similar identities (98.2%) with both human and animal strains (Fig. 1). R25 remained 100% interchangeable with Tokyo 18–25 strain (LC477366) detected in the same year (2018) from human stool and characterized as G3e bearing DS-1-like backbone with P[8] genes (Fujii et al., 2020). Both G2 genotypes (R29 and R35) belonged to the IV-A1 sub-lineage and showed 98.2% nucleotide identity with Sewage_4 strain (KX931935) detected previously from the same sewage plant in 2015 (Thongprachum et al., 2018) and akin to the epidemic strains of 2014/2015 and 2016/2017 seasons in Japan (Fujii et al., 2020; Thongprachum et al., 2018). RotaTeq, but not Rotarix, vaccine strains were detected in only 2 (5.2%) SW samples by RT-qPCR: one in March 2020 (20 copies/ml), and another in February 2022 (2.4 × 103 copies/ml).Fig. 1 Phylogenetic analysis of RVA based on partial VP7 region. The tree was constructed by the Neighbor-Joining method and drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic tree. The tree is rooted by the G18 strain and constructed with the study strains (bold, underlined with sampling time and accession number in the first bracket) and the reference strains obtained from the GenBank database. Bootstrap values ≥ 75% are shown at the branch nodes Genetic Diversity of NoVs and SVs Both NoV GI and GII increased sharply in SWs during the pandemic (Table 1). Among NoV GI-positive samples, the detection rate of the GI.3 genotype was increased from 4.3 to 13% during the pandemic. In addition, GI.1 (8.7%) and GI.6 (4.3%) were detected only during the pandemic. As shown in Fig. 2A, NGI50 and NGI60 showed 100% identities with a strain (LC521521) detected from asymptomatic/less symptomatic people in Thailand in 2018 (Phattanawiboon et al., 2020), whereas NGI30 and NGI61 remained 100% indistinguishable from epidemic strains (MN922737, MT491999), as well as environmental strains (MN752674, MN495013), detected in Taiwan, Spain, Thailand, and South Korea in 2018–2019 (Chiu et al., 2020). Both NGI62 and NGI63 were related (> 99.5% identity) to GI.1 clinical (MT492066) and environmental (MZ021974) strains. NGI49 showed 100% similarity with GI.6 strains detected in the wastewater in South Korea (MN494556) and Pakistan (OK326849) in 2018 and later reported in the patients in Tokyo in 2021 (LC646339).Fig. 2 Phylogenetic analysis of NoV GI (a), NoV GII (b), and SV (c) based on partial capsid region. The trees were constructed by the Neighbor-Joining method and drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic trees. The strains detected in this study are shown with the collection time and accession number in bold and underlined. Bootstrap values ≥ 75% are shown at the branch nodes. Asterisks represent the prototypes Among NoV GII genotypes, GII.2 (45.5%) remained the major that was mainly detected during the pandemic (Table 1). Other dominating NoV GII genotypes include GII.17 (13.6%), GII.1 (4.5%), and GII.6 (4.5%). Phylogenetic analysis demonstrated that, except the NGII39 and NGII63, other GII.2 strains remained close to the circulating GII.P16-GII.2 strain that was isolated from both sporadic cases and outbreaks in many countries including Japan (Honjo et al., 2022; Nagasawa et al., 2018), and is thought to be derived from the epidemic GII.2 strains of 2010–2012 (Fig. 2(B)). NGII37, NGII52, and NGII62 remained in a cluster with strain (LC169560) characterized as sub-lineage IIIc of GII.17 and has the similarity with outbreak strain reported in central Japan in 2015 (Thongprachum et al., 2018). In contrast, the detection rate of SVs decreased slightly (81.2–69.6%) during the pandemic, yet remained comparative to other viruses. S60, S61, and S62 strains, detected in the winter of 2021–2022, showed 100% identities with clinical strains of the GI.1 genotype that were reported from different parts of the world including China (2013–2017), Japan (2010, 2017), Russia (2012), Brazil (2010) and USA (2014) (Fig. 2(C)) (Okitsu et al., 2021). S39 and 41 remained similar to GI.2 strains detected in China in 2016–2017, while S33, S34, and S40 were clustered in the GII.3 genotype with both environmental and clinical strains collected from China and Russia earlier. The Predominance of HAdV Type F41 and the Genetic Diversity of AstVs and EVs The detection rate of AdV and EV decreased slightly (3–8%), whereas AstV increased by > 15% during the pandemic (Table 1). Genotyping was possible for 44.4% (8 of 18) of AdV which all showed 100% identity with the F41 genotype and remained largely divided into two groups (Fig. 3A). Importantly, most strains detected during the pandemic (AD38, AD40, AD60, AD61, and AD63) remained in a group with strains of lineage 1, while AD25, 26, and 37 strains detected earlier were clustered into the alternate group with strains of lineage 2 and 3 of F41 (Jasper Götting, 2022), indicating the emergence of different F41 strains during the pandemic.Fig. 3 Phylogenetic analysis of AdV (a), AstV (b), and EV (c) based on partial hexon, ORF-1b, and 5’UTR regions, respectively. The trees were constructed by the Neighbor-Joining method and drawn to scale, with branch lengths in the same units as those of the evolutionary distances used to infer the phylogenetic trees. The strains detected in this study are shown with the isolation time in bold, underlined. Bootstrap values ≥ 75% are shown at the branch nodes. The name of the disease other than AGE has been mentioned if available To determine the evolutionary relationships among AstV-genotypes, the partial ORF-1b region of 10 AstV-positive samples were sequenced. Half of them pertained to MLB (Melbourne) clade including MLB1 (AS37, AS38, AS60, and AS61) and MLB3 (AS39) showing 99–100% identities with clinical strains detected worldwide in various countries including Japan (LC694998 and LC695000) (Fig. 3B). The remaining half was related to canine AstV (CAstV), close to the strain (KY271995) characterized earlier as China-type group-2 CAstV (Zhou et al., 2017). However, both classical (HAstV) and Virginia (VA) types AstVs were not detected in this study. To find out the genetic diversity of EVs, the 5’UTR region of 10 EV-positive samples were sequenced. Half (5/10, 50%) of them remained attached to human EV-A species of CVA2, CVA4, CVA6, CVA10, and CVA16 serotypes, while 30% (3/10) strains matched with human EV-B of CVB4, E11, and E30 genotypes, and remaining 20% (2/10) fitted with human EV-C of CVA19 and CVA24 types. Among these, EV32 (CVA16), EV25 (CVA10), and EV41 (CVA19) remained relevant to strains responsible for HFMD in China, Australia, and Malaysia (Wang et al., 2022; Yi et al., 2022; Zhou et al., 2011), while EV59 (CVA4) was akin to strain (MN964082) caused herpangina in China in 2018 (Guo et al., 2020) (Fig. 3C). EV30 strain showed 98.4% identity with the outbreak strain (MZ171089) caused hemorrhagic conjunctivitis in China in 2007 (Li et al., 2022). Since HFMD, herpangina, and hemorrhagic conjunctivitis remain summer diseases (Ghaznavi et al., 2022), it explains the reason for the high detection rate of EVs in the summer (Table 2). Discussion Recently, we wrote a letter to the editor pointing out the abundance of AGE viruses in raw SW during the COVID-19 pandemic, when AGE patients in clinics were drastically reduced (Hoque et al., 2022a, 2022b, 2022c). However, the molecular characteristics of circulating strains in SW during the pandemic are not yet known. Because the emergence or reemergence of predominant genotypes through evolutionary change is a common phenomenon in AGE viruses, understanding the molecular changes in genotypes over time is absolutely essential to be prepared for impending outbreaks caused by emerging variants. SW remained the best means of determining the circulating strains, especially when the number of clinical specimens declined during the pandemic. The SWs collected in the present study remained a mixture of black (wastewater from toilets) and gray waters (all domestic wastewater except toilets) from approximately 245,000 inhabitants, coming from homes, schools, markets, farms, and hospitals (after initial treatment), together with environmental waste from rainwater. We observed that although the detection rates of SV, AdV, and EV decreased slightly with the introduction of NPIs, most enteric viruses such as RVA, NoV GI, GII, and AstV were detected more frequently at the time of the pandemic (Table 1). The SWs of this SW treatment plant were also studied in 2015–2016 (Thongprachum et al., 2018). As expected, several similarities and dissimilarities in genotypes were found between past and present data. For example, the G3-genotype of RVA remained high in both the pre- and post-pandemic periods in the present study, while the major RVA genotype was G2 in the earlier study (Thongprachum et al., 2018). Several clinical data revealed that the G2 genotype dominated in many places in Japan during 2014–2017 (Hoque et al., 2020; Khandoker et al., 2018), whereas the G3 genotype emerged in the post-vaccine era with an equine-like G3 (eG3) containing the DS-1-like genotype constellation that was firstly reported to cause an outbreak in Japan in Hokkaido in 2016 and then gradually increased (Akane et al., 2021; Okitsu et al., 2022). Importantly, RVA was detected frequently even after the introduction of RV vaccines in the national immunization program, although the RV-vaccine strains were detected in only 2 SW samples. Previously, we have shown that RV vaccines can reduce the severity of disease but cannot prevent the occurrence of RV infection (Hoque et al., 2019a, 2019b; Kawata et al., 2021; Ushijima et al., 2021), which is consistent with the present results. A similar interpretation has also been documented by other groups (Araki et al., 2016; Braeckman et al., 2012; Fujii et al., 2017; Kozawa et al., 2022; Markkula et al., 2017, 2020; Payne et al., 2019; Santos et al., 2016). Indeed, RV vaccines were originally developed to protect against serious diseases caused by commonly circulating strains (Hoque et al., 2018a, 2018b). The introduction of RV vaccination has succeeded in nearly halving the number of global RV deaths from 453,000 in 2008 to 215,000 in 2013 (Moyo et al., 2014; Tate et al., 2012). Indeed, RV vaccines continue to be successful in minimizing disease severity as well as hospitalizations and thus reducing mortality from RV infection, but the infection nevertheless remains ineradicable, showing multiple outbreaks and greater diversity of circulating RV genotypes in the post-vaccination period documented in our previous studies (Hoque et al., 2020; Okitsu et al., 2022) as well as by other groups (Gibory et al., 2022; Gikonyo et al., 2020; Tsugawa et al., 2021). A similar diversity of RV genotypes was observed in the present study at SW (Table 1). RV vaccines provide poor protection from some emerging strains like G8P[8] (Hoque et al., 2018a, 2018b). Again, since the target population for RV vaccination is infants (≤ 6 months), there is a possibility that the vaccines failed to protect older children (≥ 3 years) from infection due to not receiving the vaccine or that the effectiveness of the vaccine may have declined. RV vaccine strains were detected low in SW in earlier studies as well (Ito et al., 2021), probably because the infants typically use diapers. In agreement with the prior study (Thongprachum et al., 2018), AdV-F41, Ast-MLB1, and different species of EVs predominated in the present study (Table 1). However, globally dominant NoV GII.4 was not detected in the present study; instead, NoV GII.2 has emerged in this population. Indeed, NoV GII.2 (particularly GII.P16-GII.2) has emerged abruptly in the last 6–7 years and remained associated with both sporadic cases and outbreaks in many countries, e.g., the USA, Australia, Thailand, China, and Japan, including this community (Gao et al., 2019; Nagasawa et al., 2018; Supadej et al., 2019). Importantly, herein, we detected a high genotype diversity of AGE viruses in raw sewage in both pre-and post-pandemic eras. Although some stains looked like the animal strains (e.g., RVA from bovine/dog/cat/porcine/equine, and canine AstV) and some remained associated with different diseases (e.g., HFMD, herpangina, and hemorrhagic conjunctivitis), yet most of these viruses remained closely related to human enteric viruses. In addition, most of the strains like G1, G3 of RVA, GI.1 of NoV GI, GII.2 of NoV GII, GI.1 of SV, and MLB1 of AstV either increased or re-emerged amid the pandemic, suggesting that the normal phenomena of genotype changes remained active during the pandemic. Although these types of molecular data are deemed evidence of viral fragments, and not the infectious virus directly, the risk of impending outbreaks through exposure cannot be ruled out. Several extensive AGE outbreaks have been reported due to contamination with SW (Hafliger et al., 2000; Laine et al., 2011). Of note, nCoV was not detected in the present study by both conventional and real-time RT-PCR, suggesting that COVID-19 infection remained low in the community which was difficult to detect from the wastewater. According to WHO, the absence of nCoV in wastewater does not indicate a lack of the virus in the community (WHO, 2022). However, the possibility of inefficient recovery of RNA from enveloped viruses like nCoV cannot be ruled out. Recent evidence suggests that, unlike non-enveloped viruses, the detection of enveloped nCoV from the sewage is much more difficult, particularly from the effluent (Hata et al., 2021; Kitamura et al., 2021). Very recently, Adachi Katayama et al. (2023) demonstrated a novel highly sensitive COPMAN (Coagulation and Proteolysis method using Magnetic beads for detection of Nucleic acids) method to detect nCoV from wastewater. Since our chief objective was to determine non-enveloped diarrheal viruses from the SW, we used non-enveloped MNV as the process control and the PEG precipitation (ppt) method for the concentration of the virus, which remained the most popular and widely used method for the concentration of non-enveloped diarrheal viruses from wastewater. Nonetheless, in agreement with recent evidence (Adachi Katayama et al., 2023), the weakness of the PEG ppt method for the detection of nCoV from SW has been found in the present study. Rather than quantitative analyses, the goal of this study was to gain insight into molecular characteristics and changes in genotypes of diarrheal viruses in the community. However, samples that yielded faint and/or multiple bands were not sequenced for genotyping. Thus, some genotypes remained unidentified. One major limitation of our sequenced-based genotyping method was only a single dominating strain could be identified from a single sample of a month which could not reflect the prevalence of the infection in the community. In addition, this study did not include the examination of clinical samples of the same area. Therefore, the exact correlation between human infection and SW remained unknown. Nevertheless, a considerable length of time before and after the emergence of COVID-19, plus the genotyping results of the majority of samples with evolutionary relationships, remained sufficient to understand the overall trend of infections over this period. In conclusion, this study provides the first crucial information on the circulating strains in the community during the COVID-19 pandemic. The data reveals not only the high frequency of infections in the community but also the existence of robust genetic evolutionary features among genotypes during the pandemic. Concurrently, the present study also explains the importance of WBE during the pandemic when clinical data fail to delineate the actual scenario. WBE should be strengthened further for regular monitoring of the trend of infection and early interventions before any emerging variant attends an epidemic. Acknowledgements The research was performed by an International Research Fellow of the Japan Society for the Promotion of Science (Long-term Invitational Fellowships for Research in Japan). This work was supported by Grants-in-Aid for Japan Agency for Medical Research and Development (AMED) [grant number JP22fk0108122 and JP22wm0225006 to S.S., T.K., and H.U; and the Nihon University Research Grant for 2022. We express utmost gratitude to the former Director, Prof. Dr. M. A. Malek, and present Director, Prof. Dr. Ishtiaque M. Syed, of the Centre for Advanced Research in Sciences (CARS), the University of Dhaka, Bangladesh for allowing this collaborative study between the University of Dhaka, Bangladesh, and Nihon University School of Medicine, Japan. We gratefully acknowledge all members of the Division of Microbiology, Department of Pathology and Microbiology, Nihon University School of Medicine, for their generous cooperation throughout this work. Author contributions SAH performed the major portion of the study and wrote the manuscript. TOK performed the qPCR portion and analyzed the data. NTKP and YO helped in the study. SS, TAK, and HU received the grant and designed the study. SO, YY, NM, and HU helped with data analysis, manuscript editing, and critical comments. SH and HU supervised the whole study. All authors reviewed the manuscript. Declarations Conflict of Interest The authors have no financial or proprietary interests in any material discussed in this article. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References Adachi Katayama Y Hayase S Ando Y Kuroita T Okada K Iwamoto R COPMAN: a novel high-throughput and highly sensitive method to detect viral nucleic acids including SARS-CoV-2 RNA in wastewater Science of the Total Environment 2023 856 Pt 1 158966 10.1016/j.scitotenv.2022.158966 36162583 Akane Y Tsugawa T Fujii Y Honjo S Kondo K Nakata S Molecular and clinical characterization of the equine-like G3 rotavirus that caused the first outbreak in Japan, 2016 Journal of General Virology 2021 10.1099/jgv.0.001548 33847554 Araki K Hara M Sakanishi Y Shimanoe C Nishida Y Matsuo M Tanaka K Estimating rotavirus vaccine effectiveness in Japan using a screening method Human Vaccines & Immunotherapeutics 2016 12 5 1244 1249 10.1080/21645515.2015.1121337 26680277 Armistead I Tran A White AE Wilson E Scallan Walter EJ Trends in outpatient medical-care seeking for acute gastroenteritis during the COVID-19 Pandemic, 2020 Foodborne Pathogens and Disease 2022 19 4 290 292 10.1089/fpd.2021.0099 35020464 Braeckman T Van Herck K Meyer N Pircon JY Soriano-Gabarro M Heylen E Effectiveness of rotavirus vaccination in prevention of hospital admissions for rotavirus gastroenteritis among young children in Belgium: Case-control study BMJ 2012 345 e4752 10.1136/bmj.e4752 22875947 Chiu SC Hsu JK Hu SC Wu CY Wang YC Lin JH Molecular Epidemiology of GI.3 Norovirus Outbreaks from Acute Gastroenteritis Surveillance System in Taiwan, 2015–2019 BioMed Research International 2020 2020 4707538 10.1155/2020/4707538 32104692 Chow CM Leung AK Hon KL Acute gastroenteritis: From guidelines to real life Clinical and Experimental Gastroenterology 2010 3 97 112 10.2147/CEG.S6554 21694853 Eigner U Verstraeten T Weil J Decrease in norovirus infections in Germany following COVID-19 containment measures Journal of Infection 2021 82 6 276 316 10.1016/j.jinf.2021.02.012 33581238 Fujii Y Doan YH Wahyuni RM Lusida MI Utsumi T Shoji I Katayama K Improvement of rotavirus genotyping method by using the semi-nested multiplex-PCR with new primer set Frontiers in Microbiology 2019 10 647 10.3389/fmicb.2019.00647 30984154 Fujii Y Noguchi A Miura S Ishii H Nakagomi T Nakagomi O Takahashi T Effectiveness of rotavirus vaccines against hospitalisations in Japan BMC Pediatrics 2017 17 1 156 10.1186/s12887-017-0916-7 28693503 Fujii Y Oda M Somura Y Shinkai T Molecular Characteristics of Novel Mono-Reassortant G9P[8] Rotavirus A Strains Possessing the NSP4 Gene of the E2 Genotype Detected in Tokyo, Japan Japanese Journal of Infectious Diseases 2020 73 1 26 35 10.7883/yoken.JJID.2019.211 31564695 Gao Z Liu B Yan H Li W Jia L Tian Y Norovirus outbreaks in Beijing, China, from 2014 to 2017 Journal of Infection 2019 79 2 159 166 10.1016/j.jinf.2019.05.019 31150745 Gautam R Esona MD Mijatovic-Rustempasic S Ian Tam K Gentsch JR Bowen MD Real-time RT-PCR assays to differentiate wild-type group A rotavirus strains from Rotarix((R)) and RotaTeq((R)) vaccine strains in stool samples Human Vaccines & Immunotherapeutics 2014 10 3 767 777 10.4161/hv.27388 24342877 Ghaznavi C Sakamoto H Kawashima T Horiuchi S Ishikane M Abe SK Decreased incidence followed by comeback of pediatric infections during the COVID-19 pandemic in Japan World Journal of Pediatrics 2022 18 8 564 567 10.1007/s12519-022-00575-9 35641696 Gibory M Bruun T Flem E Dembinski JL Haltbakk I Stordal K Genetic diversity of rotavirus strains circulating in Norway before and after the introduction of rotavirus vaccination in children Journal of Medical Virology 2022 94 6 2624 2631 10.1002/jmv.27484 34837228 Gikonyo JN Mbatia B Okanya PW Obiero GFO Sang C Steele D Nyangao J Post-vaccine rotavirus genotype distribution in Nairobi County, Kenya International Journal of Infectious Diseases 2020 100 434 440 10.1016/j.ijid.2020.09.005 32898668 Guo WP Chen GQ Xie GC Du LY Tang Q Mosaic genome of Human Coxsackievirus A4 associated with herpangina and HFMD in Yancheng, China, 2016 and 2018 International Journal of Infectious Diseases 2020 96 538 540 10.1016/j.ijid.2020.05.057 32439540 Hafliger D Hubner P Luthy J Outbreak of viral gastroenteritis due to sewage-contaminated drinking water International Journal of Food Microbiology 2000 54 1–2 123 126 10.1016/s0168-1605(99)00176-2 10746582 Hata A Hara-Yamamura H Meuchi Y Imai S Honda R Detection of SARS-CoV-2 in wastewater in Japan during a COVID-19 outbreak Science of the Total Environment 2021 758 143578 10.1016/j.scitotenv.2020.143578 33221007 Honjo S Kuronuma K Fujiya Y Nakae M Ukae S Nihira H Genotypes and transmission routes of noroviruses causing sporadic acute gastroenteritis among adults and children, Japan, 2015–2019 Infection, Genetics and Evolution 2022 104 105348 10.1016/j.meegid.2022.105348 35952938 Hoque SA Iizuka I Kobayashi M Takanashi S Anwar KS Islam MT Determining effectiveness of rotavirus vaccine by immunochromatography and reverse transcriptase polymerase chain reaction: A comparison Vaccine 2019 37 39 5886 5890 10.1016/j.vaccine.2019.07.091 31451325 Hoque SA Islam MT Kobayashi M Takanashi S Anwar KS Watanabe T Our response to the letter to the editor Vaccine 2018 36 34 5110 5111 10.1016/j.vaccine.2018.05.004 30103896 Hoque SA Khandoker N Thongprachum A Khamrin P Takanashi S Okitsu S Distribution of rotavirus genotypes in Japan from 2015 to 2018: Diversity in genotypes before and after introduction of rotavirus vaccines Vaccine 2020 38 23 3980 3986 10.1016/j.vaccine.2020.03.061 32307276 Hoque SA Kobayashi M Takanashi S Anwar KS Watanabe T Khamrin P Role of rotavirus vaccination on an emerging G8P[8] rotavirus strain causing an outbreak in central Japan Vaccine 2018 36 1 43 49 10.1016/j.vaccine.2017.11.056 29183732 Hoque SA Kotaki T Pham NTK Onda Y Okitsu S Sato S Abundance of Viral Gastroenteritis before and after the Emergence of COVID-19: Molecular Evidence on Wastewater Journal of Infection 2022 10.1016/j.jinf.2022.11.007 36402208 Hoque SA Nishimura K Thongprachum A Khamrin P Thi Kin Pham N Islam MT An increasing trend of human sapovirus infection in Japan, 2009 to 2019: An emerging public health concern Journal of Infection and Public Health 2022 15 3 315 320 10.1016/j.jiph.2022.01.019 35124328 Hoque SA Thongprachum A Takanashi S Mostafa SM Saito H Anwar KS Alarming situation of spreading enteric viruses through sewage water in Dhaka city: Molecular nces Food and Environmental Virology 2019 11 1 65 75 10.1007/s12560-018-09363-z 30607905 Hoque SA Wakana A Shimizu H Takanashi S Okitsu S Anwar KS Detection of rotavirus strains in freshwater clams in Japan Food Environ Virol 2022 14 1 94 100 10.1007/s12560-021-09505-w 34981415 Imai N Gaythorpe KAM Bhatia S Mangal TD Cuomo-Dannenburg G Unwin HJT COVID-19 in Japan, January-March 2020: Insights from the first three months of the epidemic BMC Infectious Diseases 2022 22 1 493 10.1186/s12879-022-07469-1 35614394 Jasper Götting AKC Steinbrück L Heim A Molecular Phylogeny of human adenovirus type 41 lineages bioRxiv 2022 10.1101/2022.05.30.493978 Kawata K Hikita T Takanashi S Hikita H Ogita K Okitsu S Diagnosis of acute gastroenteritis with immunochromatography and effectiveness of rotavirus vaccine in a Japanese Clinic Access Microbiology 2020 2 3 acmi000085 10.1099/acmi.0.000085 32974566 Kawata K Hoque SA Nishimura S Yagyu F Islam MT Sharmin LS Role of rotavirus vaccination on G9P[8] rotavirus strain during a seasonal outbreak in Japan Human Vaccines and Immunotherapeutics 2021 10.1080/21645515.2021.1925060 34033735 Khandoker N Thongprachum A Takanashi S Okitsu S Nishimura S Kikuta H Molecular epidemiology of rotavirus gastroenteritis in Japan during 2014–2015: Characterization of re-emerging G2P[4] after rotavirus vaccine introduction Journal of Medical Virology 2018 90 6 1040 1046 10.1002/jmv.25067 29488230 Kitajima M Oka T Tohya Y Katayama H Takeda N Katayama K Development of a broadly reactive nested reverse transcription-PCR assay to detect murine noroviruses, and investigation of the prevalence of murine noroviruses in laboratory mice in Japan Microbiology and Immunology 2009 53 9 531 534 10.1111/j.1348-0421.2009.00152.x 19703247 Kitamura K Sadamasu K Muramatsu M Yoshida H Efficient detection of SARS-CoV-2 RNA in the solid fraction of wastewater Science of the Total Environmen 2021 763 144587 10.1016/j.scitotenv.2020.144587 Kozawa K Higashimoto Y Kawamura Y Miura H Negishi T Hattori F Rotavirus genotypes and clinical outcome of natural infection based on vaccination status in the post-vaccine era Human Vaccines & Immunotherapeutics 2022 18 1 2037983 10.1080/21645515.2022.2037983 35240934 Laine J Huovinen E Virtanen MJ Snellman M Lumio J Ruutu P An extensive gastroenteritis outbreak after drinking-water contamination by sewage effluent, Finland Epidemiology and Infection 2011 139 7 1105 1113 10.1017/S0950268810002141 20843387 Li J Huang F Zhang Y Ji T Zhu S Wang D Molecular analysis of Coxsackievirus A24 variant isolates from three outbreaks of acute hemorrhagic conjunctivitis in 1988, 1994 and 2007 in Beijing, China Virologica Sinica 2022 37 2 168 176 10.1016/j.virs.2022.01.024 35277374 Maria C Hrishikesh S Diarrhea 2018 StatPearls Publishing Markkula J Hemming-Harlo M Salminen MT Savolainen-Kopra C Pirhonen J Al-Hello H Vesikari T Rotavirus epidemiology 5–6 years after universal rotavirus vaccination: Persistent rotavirus activity in older children and elderly Infectious Diseases (london) 2017 49 5 388 395 10.1080/23744235.2016.1275773 Markkula J Hemming-Harlo M Savolainen-Kopra C Al-Hello H Vesikari T Continuing rotavirus circulation in children and adults despite high coverage rotavirus vaccination in Finland Journal of Infection 2020 80 1 76 83 10.1016/j.jinf.2019.09.009 31580869 Nagasawa K Matsushima Y Motoya T Mizukoshi F Ueki Y Sakon N Phylogeny and immunoreactivity of norovirus GII.P16-GII.2, Japan, winter 2016–17 Emerging Infectious Diseases 2018 24 1 144 148 10.3201/eid2401.170284 29260675 Okitsu S Khamrin P Hikita T Thongprachum A Pham NTK Hoque SA Changing distribution of rotavirus A genotypes circulating in Japanese children with acute gastroenteritis in outpatient clinic, 2014–2020 Journal of Infection and Public Health 2022 15 7 816 825 10.1016/j.jiph.2022.06.009 35759807 Okitsu S Khamrin P Takanashi S Thongprachum A Hoque SA Takeuchi H Molecular detection of enteric viruses in the stool samples of children without diarrhea in Bangladesh Infection, Genetics and Evolution 2020 77 104055 10.1016/j.meegid.2019.104055 31629889 Okitsu S Khamrin P Thongprachum A Hikita T Kumthip K Pham NTK Diversity of human sapovirus genotypes detected in Japanese pediatric patients with acute gastroenteritis, 2014–2017 Journal of Medical Virology 2021 93 8 4865 4874 10.1002/jmv.26934 33704833 Payne DC Englund JA Weinberg GA Halasa NB Boom JA Staat MA Association of rotavirus vaccination with inpatient and emergency department visits among children seeking care for acute gastroenteritis, 2010–2016 JAMA Network Open 2019 2 9 e1912242 10.1001/jamanetworkopen.2019.12242 31560386 Phattanawiboon B Nonthabenjawan N Boonyos P Jetsukontorn C Towayunanta W Chuntrakool K Norovirus transmission mediated by asymptomatic family members in households PLoS ONE 2020 15 7 e0236502 10.1371/journal.pone.0236502 32702014 Santos VS Marques DP Martins-Filho PR Cuevas LE Gurgel RQ Effectiveness of rotavirus vaccines against rotavirus infection and hospitalization in Latin America: Systematic review and meta-analysis Infectious Diseases of Poverty 2016 5 1 83 10.1186/s40249-016-0173-2 27514855 Shirato K Nao N Katano H Takayama I Saito S Kato F Development of Genetic Diagnostic Methods for Detection for Novel Coronavirus 2019(nCoV-2019) in Japan Japanese Journal of Infectious Diseases 2020 73 4 304 307 10.7883/yoken.JJID.2020.061 32074516 Supadej K Khamrin P Kumthip K Malasao R Chaimongkol N Saito M Distribution of norovirus and sapovirus genotypes with emergence of NoV GII.P16/GII.2 recombinant strains in Chiang Mai, Thailand Journal of Medical Virology 2019 91 2 215 224 10.1002/jmv.25261 29995327 Thongprachum A Fujimoto T Takanashi S Saito H Okitsu S Shimizu H Detection of nineteen enteric viruses in raw sewage in Japan Infection, Genetics and Evolution 2018 10.1016/j.meegid.2018.05.006 29753903 Tsugawa T Akane Y Honjo S Kondo K Kawasaki Y Rotavirus vaccination in Japan: Efficacy and safety of vaccines, changes in genotype, and surveillance efforts Journal of Infection and Chemotherapy 2021 27 7 940 948 10.1016/j.jiac.2021.04.002 33867267 Ushijima H Hikita T Kobayashi M Pham NTK Onda-Shimizu Y Kawagishi T The Detection of Rotavirus Antigenemia by Immunochromatographic Kits: a Case Series Clinical Laboratory 2021 10.7754/Clin.Lab.2021.210125 34655198 Wang J Liu J Fang F Wu J Ji T Yang Y Genomic surveillance of coxsackievirus A10 reveals genetic features and recent appearance of genogroup D in Shanghai, China, 2016–2020 Virologica Sinica 2022 37 2 177 186 10.1016/j.virs.2022.01.028 35234621 WHO. (2022). Wastewater surveillance of SARS-CoV-2: Questions and answers. Retrieved 28th Sept, 2022, from https://apps.who.int/iris/bitstream/handle/10665/353058/WHO-EURO-2022-5274-45038-64164-eng.pdf?sequence=4&isAllowed=y Yi L Zhang L Feng L Luan X Zhao Q Xu P Genomic analysis of a recombinant coxsackievirus A19 identified in Xinxiang, China, in 2019 Archives of Virology 2022 167 6 1405 1420 10.1007/s00705-022-05433-7 35397685 Zhang J Cao J Ye Q Nonpharmaceutical interventions against the COVID-19 pandemic significantly decreased the spread of enterovirus in children Journal of Medical Virology 2022 94 8 3581 3588 10.1002/jmv.27806 35474224 Zhou F Kong F Wang B McPhie K Gilbert GL Dwyer DE Molecular characterization of enterovirus 71 and coxsackievirus A16 using the 5' untranslated region and VP1 region Journal of Medical Microbiology 2011 60 Pt 3 349 358 10.1099/jmm.0.025056-0 21148280 Zhou H Liu L Li R Qin Y Fang Q Balasubramaniam VR Detection and genetic characterization of canine astroviruses in pet dogs in Guangxi, China Virology Journal 2017 14 1 156 10.1186/s12985-017-0823-4 28814340
PMC010xxxxxx/PMC10106811.txt	==== Front J Fr Ophtalmol J Fr Ophtalmol Journal Francais D'Ophtalmologie 0181-5512 1773-0597 Elsevier Masson SAS. S0181-5512(23)00228-0 10.1016/j.jfo.2023.02.006 Original Article Evaluation of the retina with optical coherence tomography angiography (OCTA) in patients with coronavirus (COVID-19) infection Évaluation de la rétine par angiographie par tomographie à cohérence optique (OCTA) chez les patients atteints d’une infection à coronavirus (COVID-19)Soysal G.G. a⁎ Kimyon S. b Mete A. b Güngör K. b a Ersin-Arslan Education and Research Hospital Ophthalmology Department, 27000 Gaziantep, Turkey b Gaziantep University Hospital Ophthalmology Department, Gaziantep, Turkey ⁎ Corresponding author. 17 4 2023 6 2023 17 4 2023 46 6 639645 19 11 2022 12 2 2023 © 2023 Elsevier Masson SAS. All rights reserved. 2023 Elsevier Masson SAS Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. Purpose The goal of this study is to compare the optical coherence tomography angiography (OCTA) findings in Coronavirus (COVID-19) positive adult and pediatric patients with those of healthy volunteers with the same demographic characteristics. Methods The right eye of 157 adults infected with covid, 168 healthy adult volunteers, 40 children (6–18 years of age) infected with covid, and 44 healthy children (6–18 years of age) were included in this prospective study. All participants underwent ophthalmological examination and OCTA. The OCTA findings were evaluated. Results Deep nasal density (DND), deep inferior density (DID), and deep parafoveal density (DPD) were significantly lower in the pediatric covid-affected group (PCAG) than in the pediatric healthy control group (PHCG) (P = 0.034, P = 0.029, P = 0.022 respectively). On the other hand, radial peripapillary capillary vessel density (RPCVD) intra-disc measurements were significantly higher in the PCAG compared to the PHCG (P = 0.025). There was no significant difference between the OCTA measurements of the adult covid-affected group (ACAG) and the adult healthy control group (AHCG). Conclusion In our study, significant differences were found in OCTA measurements between the covid group and the healthy control group in children. Retinal microvascular changes may occur in patients with covid infection, and these patients might be followed for long-term retinal changes. Résumé Objectif L’objectif de cette étude est de comparer les résultats de l’angiographie par tomographie à cohérence optique (OCTA) de patients adultes et pédiatriques positifs au coronavirus (COVID-19) avec des volontaires sains présentant les mêmes caractéristiques démographiques. Méthodes L’œil droit de 157 adultes infectés par la covid, 168 volontaires adultes sains, 40 enfants (6–18 ans) infectés par la covid et 44 enfants sains (6–18 ans) ont été inclus dans cette étude prospective. Tous les participants ont subi un examen ophtalmologique et une OCTA a été réalisée. Les résultats de l’OCTA ont été évalués. Résultats La densité nasale profonde (DND), la densité inférieure profonde (DID) et la densité parafovéale profonde (DPD) étaient significativement plus faibles dans le groupe pédiatrique atteint de la covid (PCAG) que dans le groupe témoin sain (PHCG) (p = 0,034, p = 0,029, p = 0,022 respectivement). D’autre part, les mesures de la densité des vaisseaux capillaires péripapillaires radiaux (RPCVD) à l’intérieur du disque étaient significativement plus élevées dans le PCAG que dans le PHCG (p = 0,025). Il n’y avait pas de différence significative entre les mesures OCTA du groupe d’adultes atteints de la covid (ACAG) et du groupe de contrôle adulte sain (AHCG). Conclusion Dans notre étude, des différences significatives ont été trouvées dans les mesures OCTA entre le groupe covid et le groupe de contrôle sain chez les enfants. Des changements microvasculaires rétiniens peuvent se produire chez les patients atteints d’une infection de la covid, et ces patients peuvent être suivis pour des changements rétiniens à long terme. Keywords Coronavirus Optical coherence tomography angiography Foveal avascular zone Retina Mots clés Coronavirus Angiographie par tomographie par cohérence optique Zone avasculaire fovéale Rétine ==== Body pmcIntroduction Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a betavirus, caused the coronavirus (COVID 19) epidemic that emerged in 2019, spreading rapidly around the world and causing a large number of deaths [1]. It is known that SARS-CoV-2 virus uses the angiotensin-converting enzyme-associated carboxypeptidase (ACE) 2 receptor to enter the cell. Angiotensin-converting enzyme 2 receptors are found on the cell membranes of type II alveolar cells in the lung and enterocytes of the small intestine, as well as on arterial and venous endothelium [2]. It is found in different cell types of the retina, including choroid and müller cells, ganglion cells, retinal vascular endothelial cells, and photoreceptor cells. It is known that the ACE 2 receptor plays a role in diabetic and hypertensive retinopathy [3]. In addition to damaging the endothelium via the ACE 2 receptor, SARS-CoV-2 virus can cause microvascular damage and coagulopathy because of complement activation and intense inflammatory response [4]. The prevalence of ocular symptoms in COVID-19 patients has been reported to range from 2 to 32% [5], [6], [7], [8]. It has been reported that COVID 19 infection causes ophthalmologic involvement such as conjunctival congestion, chemosis, conjunctivitis and enlarged vessels and increased vascular tortuosity, bleeding areas, etc. [9]. In addition, it has been reported that coronaviruses cause ocular infections in animals, including retinitis and optic neuritis [3]. In this study, our aim is to investigate the effects of COVID 19 infection on the vascular structures of the retina and optic disc in adults (19–60 years old) and children (6–18 years old) using optical coherence tomography angiography (OCTA). Materials and methods This prospective study was carried out at Gaziantep University Şahinbey Training and Research Hospital between January 2021 and July 2021. The principles of the Declaration of Helsinki were followed. Approval was granted by the Ethics Committee of Gaziantep University. Consent forms were obtained from patients and volunteers. Our study includes 157 adults with PCR positive covid infection referred from covid polyclinics, 168 healthy adult volunteers who applied to the eye diseases outpatient clinic for control, 40 children (6–18 years old) with PCR positive covid infection and 44 healthy children (6–18 years old). Patients were evaluated within 3 to 6 months after the positive result of covid 19 PCR test. Only right eyes were included in statistical analysis. Inclusion criteria for the study were; ages between 6 and 60, open optic axis, adequate pupil dilation and fixation for OCTA. Exclusion criteria were: history of previous ocular surgery, an additional systemic disease, retinal and optic disc disease, history of regular drug use, and refraction values above ± 3 diopters. OCTA assessments Patients with covid infection and healthy volunteers included in our study were evaluated by taking 3 × 3 mm macular images centered on the fovea and 4.5 × 4.5 mm optic disc images using AngioVue® (RTVue-XR, Fremont, California, USA; software version 2017.1.0.151). Patients with image quality less than 6/10 were excluded from the study. Foveal avascular zone (FAZ) area, flow area, foveal density (FD), vascular density were evaluated. Foveal density (FD), the ratio of the vascular image to the whole area in the images made with OCTA gives the density as a percentage. Density measurements were made automatically in two segments as superficial capillary plexus (SCP) and deep capillary plexus (DCP) with the OCTA device. The circle with a radius of 1 mm from the center of the fovea was evaluated as the density of the fovea, and the circle between 3 and 1 mm was considered as the density of the parafovea. The segments are divided by the device into 4 quadrants: temporal, superior, nasal, and inferior. Central macular thickness (CMT) measurement is made by applying the Quickvue module in OCTA. The optic disc images were taken with a 4.5 × 4.5 mm measurement. The device automatically calculates the average vessel densities in and around the optic disc. Measurement of radial peripapillary capillary vascular density (RPCVD) with OCTA and peripapillary retinal nerve fiber layer (PPRNFL) in a 3.45 mm diameter circle around the optic disc were also evaluated. Statistical analysis Categorical measurements were summarized as numbers and percentages, and continuous measurements as mean and standard deviation (median and minimum-maximum where necessary). Shapiro-Wilk test was used to check normal distribution. The Mann-Whitney U test was used to compare the non-normally distributed variables in the two groups. SPSS 22.0 Windows version was used in the analysis. P < 0.05 was considered significant. Results Comparison of findings of patients in the adult group (18–60 years) The mean age of the adult healthy control group (AHCG) (18–60) was 36.39 ± 9.1 years, and the mean age of the adult covid-affected group (ACAG) was 36.23 ± 9.28 years. Age distributions between the groups were homogeneous (P = 0.712). No significant difference was found between the groups in macular thickness and flow field measurements made in the adult age group. It is shown in Table 1 .Table 1 Adult group macular thickness and flow field measurements. Table 1 ACAG n = 157 AHCG n = 168 P CMT (μm) 249.31 ± 19.69 251.67 ± 18.08 0.651 FAZ area (mm2) 0.28 ± 0.12 0.26 ± 0.09 0.344 CC flow area (mm2) 2.09 ± 0.16 2.12 ± 0.12 0.077 CMT: central macular thickness; FAZ area: foveal avascular zone area; CC: choriocapillaris. P-values were measured using Mann-Whitney U test. When the vascular density measurements of SCP and DCP were examined, there was not significant difference between two groups in all parameters (P > 0.05) as shown Table 2 .Table 2 Comparison of adult group macular OCTA findings. Table 2 ACAG n = 157 AHCG n = 168 P SFD (%) 19.01 ± 6.35 19.71 ± 5.04 0.363 SPD (%) 50.85 ± 3.9 51.21 ± 2.84 0.619 STD (%) 49.15 ± 3.71 49.71 ± 3.08 0.134 SSD (%) 52.14 ± 4.26 52.23 ± 3.33 0.852 SND (%) 49.98 ± 4.46 50.48 ± 3.02 0.549 SID (%) 52.09 ± 4.28 52.58 ± 3.23 0.647 DFD (%) 34.7 ± 7.49 36.09 ± 6.28 0.278 DPD (%) 54.81 ± 3.72 54.97 ± 2.79 0.927 DTD (%) 54.73 ± 3.85 55.04 ± 3.15 0.579 DSD (%) 55.13 ± 3.98 54.9 ± 3.13 0.310 DND (%) 55.07 ± 3.93 55.31 ± 2.57 0.874 DID (%) 54.44 ± 4.22 54.52 ± 3.47 0.895 SFD: superficial foveal density; SPD: superficial parafoveal density; STD: superficial temporal density; SSD: superficial superior density; SND: superficial nasal density; SID: superficial inferior density; DFD: deep foveal density; DPD: deep parafoveal density; DTD: deep temporal density; DSD: deep superior density; DND: deep nasal density; DID: deep inferior density. P-values were measured using Mann-Whitney U test. There was not any significant difference between two groups when comparing optic disc OCTA measurements (P > 0.05 for all parameters) as shown Table 3 .Table 3 Comparison of adult group optic disc OCTA findings. Table 3 ACAG n = 157 AHCG n = 168 P PPRNFL mean (μm) 113.7 ± 11.79 112.31 ± 10.63 0.536 PPRNFL sup (μm) 113.49 ± 12.69 112.31 ± 10.63 0.737 PPRNFL inf (μm) 113.99 ± 12.65 112.77 ± 13.13 0.290 RPCVD mean (%) 52.08 ± 2.67 51.97 ± 2.64 0.702 RPCVD sup (%) 52.07 ± 2.84 51.82 ± 2.95 0.430 RPCVD inf (%) 52.02 ± 2.77 52.08 ± 2.72 0.897 RPCVD intra-disc (%) 50.85 ± 4.66 50.47 ± 5.02 0.610 PPRNFL mean: peripapillary retinal nerve fiber layer average; PPRNFL sup: peripapillary retinal nerve fiber layer superior; PPRNFL inf: peripapillary retinal nerve fiber layer inferior; RPCVD mean: radial peripapillary capillary vessel density average; RPCVD sup: radial peripapillary capillary vessel density superior; RPCVD inf: radial peripapillary capillary vessel density inferior; RPCVD intra-disc: radial peripapillary capillary vessel density intra-disc. P-values were measured using Mann-Whitney U test. Comparison of findings of patients in the pediatric group (6–18 years) The mean age of pediatric covid-affected group (PCAG) was 10.40 ± 3.02 years, and the mean age of pediatric healthy control group (PHCG) was 11.75 ± 3.86 years. Age distributions between the groups were homogeneous (P = 0.670). No significant difference was found between the groups in macular thickness and flow field measurements made in the pediatric age group. It is shown in Table 4 .Table 4 Pediatric group macular thickness and flow field measurements. Table 4 PCAG n = 40 PHCG n = 44 P CMT μm 238.4 ± 15.55 241.88 ± 18.92 0.515 FAZ area (mm2) 0.28 ± 0.12 0.28 ± 0.12 0.602 CC flow area (mm2) 2.25 ± 0.14 2.24 ± 0.1 0.349 CMT: central macular thickness; FAZ area: foveal avascular zone area; CC: choriocapillaris. P-values were measured using Mann-Whitney U test. Table 5 shows the SCP and DCP vascular density measurements between 2 pediatric groups. Deep parafoveal density (DPD), deep nasal density (DND), deep inferior density (DID) were significantly lower in PCAG compared to PHCG (P = 0.022, P = 0.034, P = 0.029, respectively). There was not a significant difference between two groups in all other measured parameters (P > 0.05).Table 5 Comparison of pediatric group macular OCTA findings. Table 5 PCAG n = 40 PHCG n = 44 P SFD (%) 19.13 ± 5.59 19.69 ± 6.78 0.775 SPD (%) 50.86 ± 3.34 51.33 ± 2.28 0.861 STD (%) 49.69 ± 3.29 49.72 ± 2.42 0.638 SSD (%) 51.87 ± 4.28 52.41 ± 2.31 0.521 SND (%) 50.14 ± 3.72 50.3 ± 2.63 0.934 SID (%) 51.7 ± 3.63 52.8 ± 2.96 0.172 DFD (%) 35.75 ± 7.87 35.1 ± 8.65 0.481 DPD (%) 55.22 ± 4.24 57.04 ± 3.39 0.022* DTD (%) 55.47 ± 3.97 56.72 ± 3.71 0.096 DSD (%) 55.69 ± 4.98 57.55 ± 3.16 0.066 DND (%) 55.44 ± 3.93 57.15 ± 3.22 0.034* DID (%) 54.53 ± 5.41 56.72 ± 4.38 0.029* SFD: superficial foveal density; SPD: superficial parafoveal density; STD: superficial temporal density; SSD: superficial superior density; SND: superficial nasal density; SID: superficial inferior density; DFD: deep foveal density; DPD: deep parafoveal density; DTD: deep temporal density; DSD: deep superior density; DND: deep nasal density; DID: deep inferior density. * P < 0.05 were considered statistically significant using Mann-Whitney U test. Radial peripapillary capillary vessel density (RPCVD) intra-disc measurements were 53.81 ± 4.75 in PCAG and 52.09 ± 3.17 in PHCG, and a statistically significant difference was found between these two measurements (P = 0.025) as shown in Table 6 .Table 6 Comparison of pediatric group optic disc OCTA findings. Table 6 PCAG n = 40 PHCG n = 44 P PPRNFL mean (μm) 111.69 ± 16.82 110.15 ± 10.29 0.691 PPRNFL sup (μm) 113.46 ± 17.18 110.88 ± 10.28 0.609 PPRNFL inf (μm) 109.63 ± 17.44 109.46 ± 11.06 0.857 RPCVD mean (%) 50.65 ± 3.01 50.03 ± 2.46 0.175 RPCVD sup (%) 50.63 ± 3 50.12 ± 2.61 0.222 RPCVD inf (%) 50.67 ± 3.45 50.03 ± 2.6 0.200 RPCVD intra-disc (%) 53.81 ± 4.75 52.09 ± 3.17 0.025* PPRNFL mean: peripapillary retinal nerve fiber layer average; PPRNFL sup: peripapillary retinal nerve fiber layer superior; PPRNFL inf: peripapillary retinal nerve fiber layer inferior; RPCVD mean: radial peripapillary capillary vessel density average; RPCVD sup: radial peripapillary capillary vessel density superior; RPCVD inf: radial peripapillary capillary vessel density inferior; RPCVD intra-disc: radial peripapillary capillary vessel density intra-disc. * P < 0.05 were considered statistically significant using Mann-Whitney U test. Discussion There is increasing evidence of impaired retinal microcirculation during SARS-CoV-2 infection due to vasculitis and coagulopathy [10]. In this study, we aimed to evaluate the microvascular changes that may be caused by COVID 19 infection in the retina using OCTA and to compare it with the findings of healthy volunteers. As a result of our study, it was found that the DPD, DID, DND values of pediatric patients with covid were statistically significantly lower and RPCVD intra-disc values were higher than the control group. No statistically significant difference was found in other findings. COVID 19 infection is thought to cause retinal changes. Invernizzi et al. detected retinal hemorrhages (9.25%), cotton blots (7.4%), dilated vessels (27.7%), and tortuous vessels (12.9%) in 54 COVID-19 patients in scanning with fundus photography [11]. They also found that retinal vein diameter directly correlates with disease severity, suggesting that this may be a non-invasive parameter for monitoring inflammatory response and/or endothelial damage in COVID 19. Lecler et al. performed FLAIR-weighted magnetic resonance imaging in 9 patients with COVID 19 infection and found abnormal findings consisting of one or more hyperintense nodules in the macular region [12]. These lesions were thought to be either direct inflammatory infiltration of the retina or microangiopathic disease resulting from viral infection. In animal model studies, conditions such as retinal vasculitis, retinal degeneration and disruption of the integrity of the blood-retina barrier were observed [13], [14], [15]. There are studies on the retinal findings of patients with COVID-19 infection, but few of them used OCTA. In a study conducted by Abrishami et al., it was observed that the mean SCP vascular densities and DCP vascular densities decreased in patients who did not have COVID-19 as a result of OCTA applied at least 2 weeks later in patients with COVID-19 infection [16]. In our study, in the comparison of the adult group, it was observed that the vascular densities of SCP and DCP were decreased in the group that had COVID 19 group, but there was not any significant difference. Similar studies showed that vascular densities decrease in patient groups with COVID 19 [3], [17]. In the study by Tiryaki Demir et al., SCP, DCP and choriocapillaris flow area values in pediatric patient groups were found to be lower in the COVID-19 group than in the control group [18]. In our study the pediatric age group, a significant difference was found between the study and control groups in terms of DPD, DND and DID measurements. It is thought that there are several reasons why the macular vessel densities of patients with COVID 19 infection, especially the deep plexus density, were decreased compared to the control group. Local foveal flow disturbance may occur as a result of an obstructive event in the vessel lumen caused by thrombotic events caused by SARS-COV-2 infection. Because SARS-COV-2 infection causes proinflammatory endothelial dysfunction, a decrease in vascular density may occur as a result of increased apoptosis and pyroptosis of endothelial cells [19]. It is thought that the deep plexus is more affected than the superficial plexus because of its distance to the large arterioles and its proximity to the high metabolic activity of the retina. The retina and choroid are among the tissues with the highest vascularization per unit area in the body. For this reason, the effects of the pathophysiological processes of systemic diseases that will cause inflammation and ischemia can be observed locally in these two tissues. COVID-19 is associated with diffuse microvascular changes; therefore, it has the potential to cause disruption of retinal and choriocapillary blood flow [20]. In a study by Abrishami et al., the FAZ area in patients with COVID-19 infection was found to be larger in the group with COVID-19 infection, but this was not statistically significant. In our study, the FAZ area in the adult age group was found to be larger in patients with COVID 19 infection than in healthy patients, and it was not statistically significant. In the pediatric age group, mean FAZ area values were found to be equal between the group with COVID 19 infection and the control group. Unlike other tissues with collateral blood vessels, retinal plexi consists of terminal arteries without anastomotic connections [21]. Since the boundary delimiting the FAZ area consists of these terminal vessels, an area particularly susceptible to ischemic changes occurs [22]. It has been thought that FAZ area enlargement may occur with capillary loss in various different retinal vascular diseases such as diabetic retinopathy and retinal vascular occlusions [23], [24]. Retinal macular microvascular changes caused by COVID-19 infection may also have increased the FAZ area. There are few studies in the literature that measured retinal nerve fiber layer (RNFL) thickness in patients with COVID-19 infection. Burgos-Blasco et al. found that peripapillary RNFL thickness was increased in patients with COVID-19 infection [25]. In another study, it was defined that peripapillary RNFL thickness increased in patients with COVID-19 infection [3]. In another study with children, it was observed that the retinal nerve fiber layer thickness increased in pediatric patients who had COVID-19 [26]. In our study, the mean RNFL thickness measurement was found to be higher in the covid group in both age groups. But the difference between the measurements was not statistically significant. The radial peripapillary capillary (RPC) plexus is a branch of the retinal arterioles and runs parallel with nerve fiber axons from the optic disc to the temporal arcades [27]. The RPC plexus is thought to be crucial for the homeostasis and function of retinal ganglion cells and their axons. The RPC plexus has an important role in providing blood flow to the RNFL. Studies have shown that there is a correlation between RPC plexus density and retinal nerve fiber layer thickness [28]. In line with these findings, RPC plexus density measurement gives information about RNFL hemostasis. In our study, when the RPCVD values were examined, it was found that it was higher in ACAG compared to AHCG. This difference was not statistically significant. When the RPCVD values were examined, it was determined that it was higher in PCAG compared to PHCG, and this difference was not statistically significant except for the RPCVD intra-disc value (P = 0.025). RNFL thickening and high RPCVD measurement in our study can be thought to be related to the initial effect of inflammation due to COVID-19 infection [29]. Our study has several limitations. First of all, treatments used by adult patients for COVID-19 infection may also cause changes in retinal vascular tissues. We could not classify and evaluate our patients according to their medications. Secondly, we were unable to examine the association of disease severity or virus titer with vascular changes in patients with COVID-19. In our study, no significant difference was observed between the OCTA values of the adult age group with COVID-19 infection and the healthy control group. However, a significant difference was observed in some OCTA values between pediatric patients and healthy volunteers. Adult patients with COVID-19 infection who participated in our study, used drugs such as favipravir or hydroxychloroquine (plaquenil), which is known to cause various changes in retinal tissue, in addition to symptomatic treatment. Patients who had COVID-19 infection in the pediatric age group received only symptomatic treatment. It can be thought that this difference may have occurred due to the effect of drugs used in the treatment of adult patients. The effects of drugs used in the treatment of covid infection on the retina can also be investigated. Conclusion Microvascular changes may not be noticed in the biomicroscopy examination of patients with COVID-19 infection. OCTA provides three-dimensional images of retinal capillary plexuses, measures FAZ area, blood flow areas, and vascular densities, giving us information about microvascular changes. It can be easily used to examine the retinal microvascular changes of patients with COVID-19 infection and to evaluate the short- and long-term effects of the infection on the retina. Evaluating the effects of this viral infection causing a pandemic on the retinal layer of the eye with a method such as OCTA that shows the retinal vascular plexuses with clear numerical data can provide useful information on the diagnosis, follow-up and treatment of the disease. For this reason, it would be beneficial to conduct more studies with more samples on this subject. Funding This work did not receive any grant from funding agencies in the public, commercial, or not-for-profit sectors. Disclosure of interest The authors declare that they have no competing interest. ==== Refs References 1 Ahn D.G. Shin H.J. Kim M.H. Lee S. Kim H.S. Myoung J. Current status of epidemiology, diagnosis, therapeutics, and vaccines for novel coronavirus disease 2019 (COVID-19) J Microbiol Biotechnol 30 2020 313 324 32238757 2 Gheblawi M. Wang K. Viveiros A. Nguyen Q. Zhong J.C. Turner A.J. Angiotensin-converting enzyme 2: SARS-CoV-2 receptor and regulator of the renin-angiotensin system: celebrating the 20th anniversary of the discovery of ACE2 Circ Res 126 2020 1456 1474 32264791 3 González-Zamora J. Bilbao-Malavé V. Gándara E. Casablanca-Piñera A. Boquera-Ventosa C. Landecho M.F. Retinal microvascular impairment in COVID-19 bilateral pneumonia assessed by optical coherence tomography angiography Biomedicines 9 2021 247 33801324 4 Magro C. Mulvey J.J. Berlin D. Nuovo G. Salvatore S. Harp J. Complement associated microvascular injury and thrombosis in the pathogenesis of severe COVID-19 infection: a report of five cases Transl Res 220 2020 1 13 32299776 5 Jevnikar K. Jaki Mekjavic P. Vidovic Valentincic N. Petrovski G. Globocnik Petrovic M. An update on COVID-19 related ophthalmic manifestations Ocul Immunol Inflamm 29 2021 684 689 33826465 6 Soltani S. Tabibzadeh A. Zakeri A. Zakeri A.M. Latifi T. Shabani M. COVID-19 associated central nervous system manifestations, mental and neurological symptoms: a systematic review and meta-analysis Rev Neurosci 32 2021 351 361 33618441 7 Domínguez-Varela I.A. Rodríguez-Gutiérrez L.A. Morales-Mancillas N.R. Barrera-Sánchez M. Macías-Rodríguez Y. Valdez-García J.E. COVID-19 and the eye: a review Infect Dis (Lond) 53 2021 399 403 33566704 8 Kumar K.K. Sampritha U.C. Prakash A.A. Adappa K. Chandraprabha S. Neeraja T.G. Ophthalmic manifestations in the COVID-19 clinical spectrum Indian J Ophthalmol 69 2021 691 694 33595502 9 Hu K. Patel J. Swiston C. Ophthalmic manifestations of coronavirus (COVID-19) [updated 2022 May 24] StatPearls [Internet] 2022 StatPearls Publishing Treasure Island (FL) 10 Magro C.M. Mulvey J. Kubiak J. Mikhail S. Suster D. Crowson A.N. Severe COVID-19: a multifaceted viral vasculopathy syndrome Ann Diagn Pathol 50 2021 151645 33248385 11 Invernizzi A. Torre A. Parrulli S. Zicarelli F. Schiuma M. Colombo V. Retinal findings in patients with COVID-19: results from the SERPICO-19 study EClinicalMedicine 27 2020 100550 32984785 12 Lecler A. Cotton F. Lersy F. Kremer S. Héran F. SFNR's COVID. Ocular MRI findings in Patients with Severe COVID-19: a retrospective multicenter observational study Radiology 299 2021 E226 E229 33591889 13 Chin M.S. Hooper L.C. Hooks J.J. Detrick B. Identification of α-fodrin as an autoantigen in experimental coronavirus retinopathy (ECOR) J Neuroimmunol 272 2014 42 50 24864013 14 Wang Y. Detrick B. Yu Z.X. Zhang J. Chesky L. Hooks J.J. The role of apoptosis within the retina of coronavirus-infected mice Invest Ophthalmol Vis Sci 41 2000 3011 3018 10967058 15 Vinores S.A. Wang Y. Vinores M.A. Derevjanik N.L. Shi A. Klein D.A. Blood-retinal barrier breakdown in experimental coronavirus retinopathy: association with viral antigen, inflammation, and VEGF in sensitive and resistant strains J Neuroimmunol 119 2001 175 182 11585619 16 Abrishami M. Emamverdian Z. Shoeibi N. Omidtabrizi A. Daneshvar R. Saeidi Rezvani T. Optical coherence tomography angiography analysis of the retina in patients recovered from COVID-19: a case-control study Can J Ophthalmol 56 2021 24 30 33249111 17 Guemes-Villahoz N. Burgos-Blasco B. Vidal-Villegas B. Donate-López J. de la Muela M.H. López-Guajardo L. Reduced macular vessel density in COVID-19 patients with and without associated thrombotic events using optical coherence tomography angiography Graefes Arch Clin Exp Ophthalmol 259 2021 2243 2249 33961108 18 Tiryaki Demir S. Dalgic N. Keles Yesiltas S. Akbas Ozyurek E.B. Karapapak M. Uke Uzun S. OCT and OCTA evaluation of vascular and morphological structures in the retina in recovered pediatric patients with COVID-19 Photodiagnosis Photodyn Ther 40 2022 103157 36244680 19 Lowenstein C.J. Solomon S.D. Severe COVID-19 is a microvascular disease Circulation 142 2020 1609 1611 32877231 20 Turker I.C. Dogan C.U. Guven D. Kutucu O.K. Gul C. Optical coherence tomography angiography findings in patients with COVID-19 Can J Ophthalmol 56 2021 83 87 33497612 21 Patton N. Aslam T. Macgillivray T. Pattie A. Deary I.J. Dhillon B. Retinal vascular image analysis as a potential screening tool for cerebrovascular disease: a rationale based on homology between cerebral and retinal microvasculatures J Anat 206 2005 319 348 15817102 22 Eldaly Z. Soliman W. Sharaf M. Reyad A.N. Morphological characteristics of normal foveal avascular zone by optical coherence tomography angiography J Ophthalmol 2020 2020 8281459 32922967 23 Murakami T. Tsujikawa A. Miyamoto K. Sakamoto A. Ota M. Ogino K. Relationship between perifoveal capillaries and pathomorphology in macular oedema associated with branch retinal vein occlusion Eye 26 2012 771 780 22653519 24 Soares M. Neves C. Marques I.P. Pires I. Schwartz C. Costa MÂ Comparison of diabetic retinopathy classification using fluorescein angiography and optical coherence tomography angiography Br J Ophthalmol 101 2017 62 68 27927677 25 Burgos-Blasco B. Güemes-Villahoz N. Donate-Lopez J. Vidal-Villegas B. García-Feijóo J. Optic nerve analysis in COVID-19 patients J Med Virol 93 2021 190 191 32648939 26 Akpolat C. Cetinkaya T. Kurt M.M. A pediatric COVID-19 study: retinal nerve fiber layer, ganglion cell layer, and alterations in choroidal thickness in swept-source OCT measurements Klin Monbl Augenheilkd 239 2022 916 922 35426103 27 Yu P.K. Cringle S.J. Yu D.Y. Correlation between the radial peripapillary capillaries and the retinal nerve fibre layer in the normal human retina Exp Eye Res 129 2014 83 92 25447563 28 Kornzweig A.L. Eliasoph I. Feldstein M. Selective atrophy of the radial peripapillary capillaries in chronic glaucoma Arch Ophthalmol 80 1968 696 702 4177355 29 Chen Y. Li J. Yan Y. Shen X. Diabetic macular morphology changes may occur in the early stage of diabetes BMC Ophthalmol 16 2016 12 26781272
PMC010xxxxxx/PMC10107012.txt	==== Front Perfusion Perfusion spprf PRF Perfusion 0267-6591 1477-111X SAGE Publications Sage UK: London, England 37037793 10.1177_02676591231169587 10.1177/02676591231169587 Editorial Lessons learned from extracorporeal membrane oxygenation use for COVID-19-Related myocarditis in China Hou Xiaotong Beijing Anzhen Hospital, 12517 Capital Medical University , Beijing, China 10 4 2023 7 2023 10 4 2023 38 5 885886 © The Author(s) 2023 2023 SAGE Publications This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections. typesetterts10 ==== Body pmcCoronavirus disease 2019 (COVID-19) is associated with myocardial injury, and may led to fulminant myocarditis. 1 However, the true mechanism of cardiac injury remains uncertain. Several mechanisms have been reported to explain the COVID-19 related myocarditis including direct myocardial injury mediated via ACE2, immune dysregulation mediated by cytokine storm and hypoxia from imbalance in oxygen supply and demand. 2 In patients with COVID-19-related fulminant myocarditis who experienced cardiogenic shock (CS) or cardiac arrest (CA), venoarterial extracorporeal membrane oxygenation (VA-ECMO) can be considered as a rescue strategy to provide temporary cardiopulmonary support allowing cardiac function recovery. 3 There have been widespread of SARS-CoV-2 infections in Chinese mainland since China adjusted public health control measures on 7 December 2022. However, little is known about the clinical characteristics and outcomes of patients with COVID-19-related myocarditis on ECMO in Chinese mainland. In this article, we aim to share our experiences and outcomes in establishing and managing ECMO in critically ill patients with COVID-19-related myocarditis in Beijing Anzhen hospital. Clinical characteristics and outcomes of patients were presented in Table 1. Five adult patients with COVID-19-related myocarditis received VA-ECMO between December 2022 and January 2023. The median age of the patients were 32 years (range, 24–53years), and 4 (80%) patients were female. None of the patients had coronary heart disease, and all had positive SARS-CoV-2 test. At ECMO initiation, the median left ventricular ejection fraction (LVEF) was 20% (range, 10–28%). The median serum lactate level was 10.1 mmol/L (range, 5.1–18.0 mmol/L), median PH was 7.36 (6.85–7.42), and median vasoactive inotropic score (VIS) was 60 (range, 5–223). Three (60%) patients had an increased high-sensitivity I-troponin (hsTNI) of greater than 27,181 ng/L, and these patients suffered from CS of the Society for Cardiovascular Angiography and Interventions (SCAI) stage E. 4 Three (60%) patients had ventricular rhythm disorders, and 2 (40%) patients received extracorporeal cardiopulmonary resuscitation (ECPR). Three (60%) patients received intra-aortic balloon pump (IABP) for left ventricular unloading. The median time on ECMO was 204 h (range, 37–408 h). Two (40%) patients were weaned from mechanical ventilation during ECMO support, and survived to hospital discharge. Among the three non-survivors, two died on ECMO, and one died of multi-organ failure after successfully weaning from VA-ECMO.Table 1. Clinical characteristics and outcomes of patients with COVID-19-related myocarditis on ECMO. Variables Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Age, years 32 53 47 27 24 Sex Female Female Female Male Female Body mass index, kg/m2 19 23 21 18 21 Coronary heart disease No No No No No Pregnancy No No No No No Ventricular rhythm disorders Yes No Yes No Yes ECPR Yes No No No Yes IABP use No Yes Yes No Yes Vasoactive inotropic score 31 223 5 60 20 SCAI stage of CS E E C D E Physiologic parameters LVEF, % 10 12 28 25 20 PH 6.85 7.29 7.41 7.42 7.36 Troponin I, ng/L >27,181 >27,181 5462 19,432 >27,181 BNP, ng/L 2510 >4885 1955 903 1220 Serum lactate, mmol/L 16.0 18.0 5.1 7.1 10.1 Serum creatinine, umol/L 161 202 99 110 67 Platelet, ×109/L 102 88 316 235 208 IL-6, ng/L 211 1555 15 19 148 Positive SARS-CoV-2 test Yes Yes Yes Yes Yes Early awake ECMO No No Yes Yes No Outcomes ECMO duration, hours 37 408 204 134 172 On-support mortality Yes No No No Yes In-hospital mortality Yes Yes No No Yes Cause of mortality MOF MOF - - Stroke COVID-19, coronavirus disease 2019; ECMO, extracorporeal membrane oxygenation; ECPR, extracorporeal cardiopulmonary resuscitation; IABP, intra-aortic balloon pump; SCAI, the Society for Cardiovascular Angiography and Interventions; CS, cardiogenic shock; LVEF, left ventricular ejection fraction; BNP, B-type natriuretic peptide; SARS-CoV-2, severe acute respiratory syndrome-coronavirus-2; MOF, multi-organ failure. Fulminant myocarditis is a life-threatening condition characterized by severe myocardial inflammation with myocardial edema and myocyte necrosis. In our series, COVID-19-related myocarditis occurred more frequently in women, and mortality was 60%, similar to the published rate of Extracorporeal Life Support Organization Registry. 5 However, Hao and colleagues 6 reported a low mortality of 28% in patients who received VA-ECMO for non-COVID-19-related myocarditis. The degree of myocardial injury seemed to be higher in COVID-19-related myocarditis as compared to non-COVID-19-related myocarditis in China. In this context, three patients had severely impaired LVEF and presented with rapidly progressive CS (from SCAI stage C to E within 24 h after admission). At present, the optimal timing of ECMO use in COVID-19-related myocarditis remains uncertain. It had been demonstrated that cardiac arrest prior to ECMO, lower pH and higher lactate were independently associated with in-hospital death in fulminant myocarditis supported with VA-ECMO. 6 Among the five included patients, two received VA-ECMO support at SACI stage C or D and survived to hospital discharge, whereas the other three patients at SACI stage E had lower PH and higher lactate, and died in hospital, potentially indicating that SACI stage was associated with mortality in these patients. Although decision-making by clinicians often involves many patient and contextual factors and remains difficult, our series might suggest that VA-ECMO should be considered early for patients with COVID-9-related myocarditis who presented in CS, especially for patients with severe myocardial damage. The SCAI CS classification system could help clinicians at bedside to identify the timing of ECMO initiation. In summary, patients with COVID-19-related fulminant myocarditis presented with rapidly progressive cardiogenic shock, and ensuring effective and timely ECMO support is key to favorable outcomes in these patients. Further studies are still needed to determine the outcomes and timing of VA-ECMO use for COVID-19-related fulminant myocarditis. ==== Refs References 1 Barhoum P Pineton de Chambrun M Dorgham K , et al. Phenotypic Heterogeneity of Fulminant COVID-19--Related Myocarditis in Adults. J Am Coll Cardiol 2022; 80 (4 ): 299–312.35863846 2 Okor I Bob-Manuel T Price J , et al. COVID-19 Myocarditis: An Emerging Clinical Conundrum. Curr Probl Cardiol 2022; 47 (9 ): 101268.35644500 3 Wang L Yang F Wang X , et al. Predicting mortality in patients undergoing VA-ECMO after coronary artery bypass grafting: the REMEMBER score. Crit Care 2019; 23 (1 ): 11.30635022 4 Jentzer JC van Diepen S Barsness GW , et al. Cardiogenic shock classification to predict mortality in the cardiac intensive care unit. J Am Coll Cardiol 2019; 74 (17 ): 2117–2128.31548097 5 Tonna JE Tan CS Hryniewicz K , et al. Outcomes after extracorporeal life support for COVID-19 myocarditis: an analysis of the Extracorporeal Life Support Organization Registry. Crit Care 2022; 26 (1 ): 235.35922832 6 Hao T Jiang Y Wu C , et al. Clinical outcome and risk factors for acute fulminant myocarditis supported by venoarterial extracorporeal membrane oxygenation: An analysis of nationwide CSECLS database in China. Int J Cardiol 2023; 371 : 229–235.36174824
PMC010xxxxxx/PMC10108552.txt	==== Front Curr Probl Cardiol Curr Probl Cardiol Current Problems in Cardiology 0146-2806 1535-6280 Elsevier S0146-2806(23)00153-6 10.1016/j.cpcardiol.2023.101736 101736 Article Remote consultations: review of guiding themes for equitable and effective delivery Khanji Mohammed Y. MBBCh, PhD abcd# Gallagher Angela M. abd Rehill Nirandeep de Archbold R. Andrew abd a Newham University Hospital, Barts Health NHS Trust, London, United Kingdom b Barts Heart Centre, St Bartholomew's Hospital, Barts Health NHS Trust, London, UK c NIHR Barts Biomedical Research Centre, William Harvey Research Institute, Queen Mary d Cardiovascular Disease Prevention and Proactive Care, UCLPartners, London, UK e UCLPartners Academic Health Science Network, London, UK # Corresponding author: Dr Mohammed Y Khanji, MBBCh, PhD, Newham University Hospital, Barts Health NHS Trust, Glen Road, London E13 8SL, UK. +44 (0)20 7363 8846. ⁎ Joint first authorship 17 4 2023 8 2023 17 4 2023 48 8 101736101736 © 2023 The Author(s) 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. The global coronavirus disease (COVID) -19 pandemic has led to a rapid transformation in the ways in which outpatient care is delivered. The need to minimise the risk of viral infection and transmission through social distancing resulted in the widespread adoption of remote consultations, traditional face-to-face appointments ceasing almost overnight in many specialties. The transition to remote consultations had taken place far faster than anticipated and under crisis conditions. As we work towards the “new normal”, remote consultations have become an integral part of outpatient provision in secondary care. Adapting to this change in clinical practice requires a judicious approach to ongoing service development to ensure safe, effective, and equitable care for all patients. Medical societies have provided some initial guidance around effective delivery. In this article we discuss the potential benefits, limitations, types of remote consultations, and factors that require consideration when deciding on patient suitability for remote consultation in a hospital setting. We use cardiology as a specialty exemplar, although many of the principles will be equally applicable to other medical specialties. ==== Body pmcIntroduction The global coronavirus disease (COVID) -19 pandemic has led to a rapid transformation in the ways in which outpatient care is delivered. The need to minimize the risk of viral infection and transmission through social distancing resulted in the widespread adoption of remote consultations, traditional face-to-face appointments ceasing almost overnight in many specialties. The National Health Service (NHS) Long Term Plan, published ahead of the pandemic in January 2019, set a goal of reducing face-to-face consultations by a third in five-years through the creation of a more digitally-enabled outpatient service.1 The transition to remote consultations has taken place far faster than anticipated and under crisis conditions. As we work towards the ‘new normal’, remote consultations are expected to remain an integral part of outpatient provision in secondary care. Adapting to this change in clinical practice requires a judicious approach to ongoing service development to ensure safe, effective, and equitable care for all patients. Medical societies have started to provide some guidance around effective delivery.2 , 3 In this article we discuss the potential benefits, limitations, types of remote consultations, and factors that require consideration when deciding on patient suitability for remote consultation in a hospital setting, with cardiology used as a specialty exemplar. Potential benefits of remote consultations Remote clinics use telephone calls or video conferencing operating on mobile applications or online platforms, respectively, to enable real-time (synchronous) interactions between patients and clinicians at distant sites. Remote consultations offer several potential advantages to patients beyond the primary safety aim which arose from COVID-19 (see Table 1 for a summary of the potential benefits and limitations). These include greater convenience; reduced travel which might be particularly relevant for those who live in rural communities, have physical disabilities, or have care commitments; reduced time away from work; reduced cost; and greater access to services. Potential benefits for the healthcare system include increased efficiencies in time and cost; reduced waiting list times; and greater flexibility in service delivery models, something which might also be welcomed by individual clinicians. Reduced patient journeys, by car and hospital transport, are positive changes for the environment.Table 1 Patient and clinical factors to be considered when triaging patients to remote or face-to-face consultations Table 1 Potential benefits of remote consultations Potential limitations of remote consultations Patient Real-time interaction at a distance Inability to express symptoms or problems effectively Convenience (e.g., for those with childcare needs, disabilities etc.) Privacy and data protection breaches Travel cost saving Reduced satisfaction from less clinical interaction (physical contact, body language, examination, clinic investigations etc.) Saves time (reduced travel time, reduced time away from home/work) Inability to conduct physical examination Greater access to services Peri-visit tests less readily available (bloods, X-ray, ECG, etc.) Healthcare system Greater flexibility in service delivery models Limited ability to provide urgent prescriptions Reduced requirement for hospital waiting areas Need for staff training for effective delivery Increased efficiencies in cost Potential for clinical risk from reduced ability to identify deteriorating patients Reduced risk of nosocomial infection Need for robust, potentially costly, clinical governance and local data protection systems Other (environment/ societal) Reduced pollution from vehicle travel Higher energy consumption from internet data use/storage with potential impact on environment and climate change Potential for innovation and software development Potential limitations of remote consultations The replacement of traditional face-to-face appointments by remote consultations brings with it concerns regarding clinical risk in the diagnosis and management of patients, safeguarding and confidentiality, and patient acceptability, and the need to mitigate inequality in accessing care.4 The main limitation of all types of remote consultation is the inability to conduct a physical examination of the patient. Moreover, blood tests and other standard investigations which might previously have been performed immediately before or after the outpatient appointment such as an electrocardiogram, a chest X-ray or spirometry, cannot be readily organised. Nor can a prescription be handed directly to the patient at the conclusion of the clinical assessment. In 2018, the United Kingdom (UK) General Medical Council (GMC) updated the medical curriculum for doctors to include training on communication for remote consultations.5 Successful consultations rely on clear and effective communication but also an empathetic patient-centred care approach, which can be challenging to achieve remotely when exchange of nonverbal and verbal cues can be absent or easily missed.6 This increases the risk of interactions becoming more transactional with lower patient engagement and satisfaction. The GMC and NHS England have provided guidance for clinicians on factors which influence the safety of remote consultations and in which circumstances face-to face management may be preferable.7 Types of remote consultations Telephone consultations Telephone is a widely available and familiar method of communication, virtually all patients having access to a landline or a mobile device. Qualitative studies have indicated that telephone consultations are usually more focused than face-to-face encounters.8 This contributes to increased efficiency; however, it may also hinder holistic practice. Language can be a significant barrier to effective telephone consultations. In the 2011 UK Census for example, over four million people in England did not report English as their first language. Even with the use of interpretation services or with assistance from friends or family it can be difficult to obtain an accurate history, deliver information at an appropriate level, or gauge understanding by phone. The flexibility that telephone consultations offer is one of its major appeals, but this is also associated with downsides. Patients may not be available, particularly if the call is earlier or later than scheduled, or they may be in a public or work environment affecting their engagement in the process and necessitate the need for repeated calls, in turn affecting clinic schedules. Problems can also arise due to poor mobile phone reception. Video consultations Video consultations have the added benefit over telephone consultations of the clinician and patient being able to see each other. This facilitates nonverbal communication and allows visual examination. Video consultations are more technologically demanding than telephone consultations in device availability, set-up, and connectivity, both for the patient and the clinician. For these reasons, “tech-savvy” patients are likely to be more comfortable with them, at least initially. Digital exclusion of patients who do not have the necessary access, confidence or skills to use the service, thereby leading to unequal healthcare opportunities, are more likely to affect the elderly, those who have cognitive or sensory impairment, and the socio-economically deprived. Triage to remote or face-to-face consultation Over-simplified administrative allocations to appointment type, not accounting for relative benefits and limitations, have worsened tensions between quality of care and efficiency of care over the course of the pandemic.9 Triage of outpatient clinic referrals has taken on a new importance since the shift to remote delivery, as careful assessment of referrals is required to ensure, as far as is possible, the safety and effectiveness of the encounter. Although a face-to-face consultation can be arranged after the initial remote review if required, this may lead to delays in diagnosis and treatment and is an inefficient use of resources. From a clinical perspective, the main determinant of triage outcome is the question to be addressed by the assessment, and how this is best answered, for example whether physical examination and/or investigations are required on the day. However, patient factors also need to be considered. New patient appointments are usually the first interaction between the patient and the clinician within the relevant specialty. The accuracy and quality of the information provided in the referral is therefore key to appropriate triage. By contrast, follow-up appointments are usually made with the benefit of corroborated knowledge of the patient's history (from the first consultation or from a hospital discharge summary) and are often to discuss the results of investigations and/or to reassess symptoms, factors which may mean that a face-to-face consultation is not necessary. The nature of the information to be given to the patient (“good news” or “bad news”) may also affect triage outcome. It is important to establish the patient's preference for method of consultation and to determine the most appropriate means for communication. Commonly, this is achieved by the provision of patient information leaflets ahead of appointments. However, for many patients with cognitive or sensory impairment or those who face language barriers or literacy issues these resources may not be accessible or there may be an inability for concerns to be voiced prior to the appointment. The patient's technology and digital literacy also need to be considered for successful triage. Going forward, patient suitability for telephone and/or video consultation should be included in the referral to facilitate decision-making. Outpatient consultation outcomes should also document the most suitable method for subsequent consultations. We provide a suggested strategy for identifying patients who are most suited to remote/virtual clinic consultations, complementing the in-depth pathway provided by the GMC (Figure 1 ).7 Pathways may need to be modified based on experience, outcome data, and local healthcare system factors.Figure 1 Patient and clinical factors which influence suitability for remote consultations. Figure 1 Specialist cardiology remote clinics Cardiology is in a unique position to benefit from the advantages offered by remote consultations to healthcare organizations and patients. The increasingly widespread use of home cardiovascular monitoring by individual patients provides information which can be used to assist clinical decision-making during remote consultations. Furthermore, formal technology-enabled care services (TECS) have expanded considerably in recent years. For patients with chronic conditions such as heart failure, these services can remotely monitor patients and provide feedback to the clinician on important parameters including heart rate, blood pressure, arterial oxygen saturation, and body weight to guide management decisions. Although these data are not a direct substitute for face-to-face physical assessment, their availability circumvents to some extent the major limitation of remote consultations, they contribute important diagnostic information, are crucial to the up- (or down-) titration of heart failure medication, antihypertensive therapy, and secondary prevention medication for atherosclerotic disease, and they encourage self-management.10 Follow-up of patients after procedures such as catheter ablation for arrhythmia, when long-term management is primarily determined by symptoms rather than by physical assessment, is well suited to remote consultations.11 The availability of wearable technology, mobile applications, and self-monitoring devices also allow patients to record single lead ECG rhythm strips which play a valuable role in the diagnosis of paroxysmal arrhythmia.12 , 13 Many patients who have arrhythmia management devices, implantable loop recorders, or pulmonary artery pressure sensors benefit from the convenience of remote device monitoring. Conclusions A hybrid approach which utilises both face-to-face and remote consultations is the expected model for the delivery of outpatient care in the coming years. It seems likely that the dramatic shift to remote consultations which arose due to the COVID-19 pandemic will be modulated to some degree by the advantages of face-to-face assessment for new patients, while remote consultations are retained for the majority of follow-up appointments. Careful triage is required to ensure equitable, safe and effective consultations. Changes in practice should be evaluated based on outcomes as well as patient and clinician experience. Funding: No specific funding was received for this work. Declaration of interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. ==== Refs References 1 NHS. Online version of the NHS Long Term Plan. Nhs. 2020. p. 1. https://www.longtermplan.nhs.uk/online-version/(31 March 2023) 2 Getting It Right First Time - GIRFT. 2019. https://www.gettingitrightfirsttime.co.uk/medical-specialties/cardiology/(31 March 2023) 3 Effective remote consultations \| RCP London. https://www.rcplondon.ac.uk/education-practice/courses/effective-remote-consultations (31 March 2023) 4 Daily Insight: A remote risk? \| News \| Health Service Journal. https://www.hsj.co.uk/daily-insight/daily-insight-a-remote-risk/7030869.article (31 March 2023) 5 General Medical Council Outcomes for graduates 2018 Gen. Med. Counc. 2018 11 12 https://www.gmc-uk.org/-/media/documents/outcomes-for-graduates-2020_pdf-84622587.pdf (31 March 2023) 6 Vandermolen S Ricci F Chahal CAA ‘The digital cardiologist’: how technology is changing the paradigm of cardiology training Curr Probl Cardiol Mosby 47 2022 101394 7 General Medical Council Remote consultations - GMC Gen. Med. Counc. 2018 https://www.gmc-uk.org/ethical-guidance/ethical-hub/remote-consultations (31 March 2023) 8 Hewitt H Gafaranga J McKinstry B. Comparison of face-to-face and telephone consultations in primary care: Qualitative analysis Br J Gen Pract Royal College of General Pract 60 2010 e201 9 Greenhalgh T Rosen R Shaw SE Planning and evaluating remote consultation services: a new conceptual framework incorporating complexity and practical ethics Front Digit Heal Frontiers 0 2021 103 10 Bekfani T Fudim M Cleland JGF A current and future outlook on upcoming technologies in remote monitoring of patients with heart failure Eur J Heart Fail Eur J Heart Fail 23 2021 175 185 33111389 11 Honarbakhsh S Sporton S Monkhouse C Lowe M Earley MJ Hunter RJ. Remote clinics and investigations in arrhythmia services: what have we learnt during Coronavirus disease 2019? Arrhythmia Electrophysiol Rev 10 2021 120 124 12 Carrington M Providência R Chahal CAA Monitoring and diagnosis of intermittent arrhythmias: evidence-based guidance and role of novel monitoring strategies Eur Hear J Open Oxford Academic 2 2022 13 Carrington M Providência R Chahal CAA Clinical applications of heart rhythm monitoring tools in symptomatic patients and for screening in high-risk groups Europace Oxford Academic 24 2022 1721 1729
PMC010xxxxxx/PMC10112300.txt	==== Front Ann Biomed Eng Ann Biomed Eng Annals of Biomedical Engineering 0090-6964 1573-9686 Springer International Publishing Cham 37071282 3209 10.1007/s10439-023-03209-x Letter to the Editor Curious Questions About Covid-19 Pandemic with ChatGPT: Answers and Recommendations http://orcid.org/0000-0002-3668-2336 Tekinay Osman Nuri [email protected] grid.449840.5 0000 0004 0399 6288 Department of Business Administration, Institute of Graduate Studies, Yalova University, Yalova, Turkey Associate Editor Stefan M. Duma oversaw the review of this article. 18 4 2023 2023 51 7 13711373 11 4 2023 12 4 2023 © The Author(s) under exclusive licence to Biomedical Engineering Society 2023 This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. This article aims to answer frequently asked questions about the Covid-19 pandemic using ChatGPT and contribute to the spread of accurate information about the pandemic. The article provides general information about the ways Covid-19 is spread, symptoms, diagnosis, treatment, vaccines and pandemic management. It also provides advice on infection control, vaccination campaigns and emergency preparedness. Keywords Covid-19 ChatGPT Chatbots AI issue-copyright-statement© Biomedical Engineering Society 2023 ==== Body pmc Dear Editor, Covid-19 was declared a “global pandemic” by the WHO on March 11, 2020 [1]. Following this declaration, the Covid-19 pandemic has become one of the biggest global health crises of recent years and still poses a major threat worldwide. Therefore, it is extremely important to spread accurate information about the pandemic and fight against misinformation. This article aims to provide answers to frequently asked questions about the Covid-19 pandemic using ChatGPT and contribute to the spread of accurate information about the pandemic. Question One What are popular questions about Covid-19 around the world? Answer from ChatGPT Popular questions about Covid-19 around the world include:What is Covid-19 and how does it spread? What are the symptoms of Covid-19? Are there vaccines against Covid-19? How effective and safe are vaccines? Is there a cure for Covid-19? Why does Covid-19 cause more serious symptoms in some people? How can Covid-19 be prevented? Why is wearing a mask and social distancing important? Are there different types of Covid-19? What are the long-term effects of Covid-19? Why is Covid-19 more common and deadly in some countries? When can there be a complete normalization against Covid-19? Question Two What are the answers to these questions? Answer from ChatGPT What is Covid-19 and how is it spread? Covid-19 is an infectious disease caused by SARS-CoV-2, a virus. It is spread by spreading droplets or aerosols from people who have the virus through coughing or sneezing. It can also be transmitted by touching surfaces that carry the virus or by contact with people who carry the virus. What are the symptoms of Covid-19? Symptoms of Covid-19 include fever, cough, shortness of breath, muscle aches, headache, fatigue, loss of taste and smell. Some patients have mild symptoms, while others may develop more serious symptoms. Are there vaccines against Covid-19? How effective and safe are vaccines? Yes, vaccines against Covid-19 are available and used worldwide. The effectiveness and safety of vaccines may vary depending on the different types of vaccines and manufacturers. Is there a cure for Covid-19? Many different medicines and treatment methods are used to treat Covid-19, but there is no definitive cure yet. Why does Covid-19 cause more serious symptoms in some people? Covid-19 can cause different symptoms depending on people’s immune systems and general health. The elderly, people with diabetes, obese people and people with other chronic diseases may be more severely affected by Covid-19. How can Covid-19 be prevented? Why is wearing a mask and social distancing important? To prevent the spread of Covid-19, mask wearing, social distancing and hand hygiene measures should be taken. Wearing a mask prevents the spread of droplets when coughing or sneezing, while social distancing prevents person-to-person transmission of the virus. Are there different types of Covid-19? The different strains of Covid-19 have not yet been identified, but different variants have occurred. These variants show some changes in the characteristics of the virus and some may spread faster or cause more severe symptoms. What are the long-term effects of Covid-19? The long-lasting effects of Covid-19 are associated with a condition known as “long Covid”. In this condition, some people still feel symptoms even after they have recovered from the virus. These symptoms include fatigue, shortness of breath, muscle and joint pain, headaches, anxiety, depression and memory problems. Exactly how Long Covid occurs and what the treatment is still under investigation. Why is Covid-19 more common and deadly in some countries? There are many reasons why Covid-19 is widespread and deadly. These include population density, health infrastructure, social support networks, economic factors, government policies and social behavior. Different outcomes can occur because some countries have fought the pandemic quickly and effectively, while others have been weak. When can there be a complete normalization against Covid-19? While it is difficult to give an exact date for when there will be a full normalization against Covid-19, it is possible that, together with vaccination programs and other measures, the pandemic can be brought under control. However, how long this process will take may vary depending on vaccination rates, new variants and other factors. Question Three Do you have advice on infection control, vaccination campaigns and emergency preparedness? Answer from ChatGPT Yes, when it comes to infection control, it is important for individuals and communities to follow hygiene rules such as wearing masks, social distancing, frequent hand washing and hygiene to prevent the spread of outbreaks. Governments also need to take early detection and isolation measures to prevent the spread of outbreaks. Vaccination is one of the most important methods for controlling outbreaks. Vaccination of individuals is important for both their own health and the health of the community. Therefore, it is important for governments to organize vaccination campaigns and make vaccines available to the public free of charge. In terms of emergency preparedness, governments, health organizations, civil society organizations and other relevant institutions need to come together to respond quickly and effectively in emergencies. Preparedness plans for emergencies such as outbreaks, planned and coordinated management of resources, accurate public information and public support are also important for emergency preparedness. Question Four Finally, is there anything you want to add? Answer from ChatGPT As the Covid-19 pandemic is still ongoing, it is important that everyone fulfills their personal and societal responsibilities to prevent the spread of infection. In addition, scientists, health workers and many other people are working hard to fight the disease. People’s resilience and solidarity are also crucial during a pandemic. By supporting each other, we can solve problems together. Conclusion Artificial intelligence technologies are increasingly being used in the healthcare sector. The implications of these technologies in healthcare include more accurate diagnosis of diseases, faster and more effective treatment, improved patient care, and more accurate and secure health records. AI can also play an important role during global health crises such as pandemics. For example, an AI-based system could help decision-makers to take the right measures by predicting the speed at which the disease is spreading. However, the use of AI technologies still faces some challenges. For example, an AI system may give inaccurate results due to errors or misunderstandings due to human factors. Moreover, there are concerns about the privacy and security of health data. Therefore, the use of AI technologies in the healthcare sector should be accompanied by strict monitoring of regulatory mechanisms and implementation of appropriate education and information programs. In conclusion, the Covid-19 pandemic has had and continues to have a major impact across the world. Many strategies and measures have been taken to combat the pandemic; however, more work is needed to completely end the pandemic. In this article, we tried to answer many questions such as what is Covid-19, how it spreads, symptoms, treatment, prevention and normalization process with ChatGPT. We made suggestions on infection control, vaccination campaigns and emergency preparedness. As the whole world, we must continue to work together and support each other to fight this pandemic. Acknowledgements The author acknowledges that certain parts of this article were generated by ChatGPT (powered by OpenAI’s language model GPT-3.5; http://openai.com). Editing was done by the author. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Data Availability Not applicable. Declarations Conflict of interest No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript. The author declare no conflict of interest. Ethical Approval This study does not include any individual-level data and thus does not require any ethical approval. Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs Reference 1. Ministry of Health, T.C. Pandemic. 2020. https://covid19.saglik.gov.tr/TR-66494/pandemi.html.
PMC010xxxxxx/PMC10114314.txt	==== Front J Infect J Infect The Journal of Infection 0163-4453 1532-2742 The British Infection Association. Published by Elsevier Ltd. S0163-4453(23)00210-4 10.1016/j.jinf.2023.04.010 Letter to the Editor The effect of bebtelovimab on clinical outcomes in patients with COVID-19: A meta-analysis Luo Jie 1 Department of Nephrology, Chengdu First People’s Hospital, Chengdu, Sichuan, China Li Anthony 1 School of Medicine, Queen’s University, Kingston, Canada Liu Changying 1 Department of Geriatrics, People’s Liberation Army, The General Hospital of Western Theater Command, Chengdu, China Wang Yushu Chengdu West China Clinical Research Center, Chengdu, Sichuan, China Tran Carolyn Schulich School of Medicine & Dentistry, Western University, London, Canada Ao Guangyu ∗ Department of Nephrology, Chengdu First People’s Hospital, Chengdu, Sichuan, China ∗ Correspondence to: No.18 Wanxiang North Road, High-tech District, Chengdu 610095, Sichuan, China. 1 Contributed equally to this work. 1 Contributed equally to this work. 1 Contributed equally to this work. 19 4 2023 7 2023 19 4 2023 87 1 6871 17 4 2023 © 2023 The British Infection Association. Published by Elsevier Ltd. All rights reserved. 2023 The British Infection Association Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcDear Editor, We read the article in this journal by Hsu et al. with great interest regarding the effect of molnupiravir on post-acute outcomes of patients with COVID-191. As we pass three years since the World Health Organization declared the COVID-19 pandemic a global health emergency, the newest lineages of the Omicron subvariant of COVID-19 continue to show expanding immune escape properties, underlining the need for novel effective treatment modalities2. Bebtelovimab is a neutralizing monoclonal antibody (mAb) that is administered as a single 175 mg IV dose to target the spike protein of SARS-CoV-23. Its potency against SARS-CoV-2 Omicron, BA.2 Omicron, and Delta variants has been demonstrated and was found to be extremely particularly against the BA.4 and BA.5 sublineages2, 3. Bebtelovimab was developed by Eli Lilly and received emergency use authorization by the United States Food and Drug Administration in February 2022 based on promising phase 2 trial results against Omicron sublineages3. However, this emergency use authorization was revoked in November 2022 as it was no longer expected to neutralize the circulating BQ.1 and BQ.1.1 dominant Omicron sublineages4. To date, no systematic review or meta-analysis has been published in the literature exploring the association between bebtelovimab treatment and patient outcomes in COVID-19 cases. In this study, we present the first meta-analysis in the literature that investigates the effects of bebtelovimab administration on the prognosis of patients with COVID-19. Between December 1, 2019, and March 15, 2023, an electronic search was conducted in the databases of PubMed, Embase, the Cochrane Library, Scopus, medRxiv, and bioRxiv. No limitations on language, time period, or publishing were imposed. The following MeSH (Medical Subject Heading) terms and search terms were used: (“coronavirus disease 2019 or 2019-nCoV or SARS-CoV-2 or COVID-19 or novel coronavirus”) AND (Bebtelovimab or LY-CoV1404 or LY3853113). Between December 1, 2019, and March 15, 2023, an electronic search was conducted in the databases of PubMed, Embase, the Cochrane Library, Scopus, medRxiv, and bioRxiv. No limitations on language, time period, or publishing were imposed. The following MeSH (Medical Subject Heading) terms and search terms were used: (“coronavirus disease 2019 or 2019-nCoV or SARS-CoV-2 or COVID-19 or novel coronavirus”) AND (Bebtelovimab or LY-CoV1404 or LY3853113). The following were the inclusion criteria: (1) patients with confirmed COVID-19; (2) Bebtelovimab treatment and control groups (placebo, standard of care, or other treatments) were compared for clinical outcomes. Additionally, we gathered data on the initial characteristics of the studies and participants, such as the first author's name, the year of publication, the study design, the participants' country of origin, their age, gender, the usage of bebtelovimab, and outcomes of interest (mortality and disease severity). Review Manager, version 5.2, was used to conduct the statistical analysis (Cochrane Collaboration, Oxford). With a 95% confidence interval, the odds ratio (OR) was used to assess dichotomous variables. Using the I2 statistic and the Cochran's Q test, we evaluated the heterogeneity. Statistical significance is defined as a P value<0.05. The protocol for this meta-analysis is registered with PROSPERO (International Prospective Register of Systematic Reviews; registration number CRD42023409064). In this meta-analysis, a total of 7 studies5, 6, 7, 8, 9, 10, 11 involving 12,889 adult COVID-19 patients, including 7138 in the bebtelovimab group and 5751 in the control group arm, were found through a comprehensive literature search. Other therapy groups (not including bebtelovimab) were either Sotrovimab or nimatrelvir-ritonavir. Table 1 lists patient demographics and study population characteristics. All included studies originated in the United States. One study was an RCT and the other studies were retrospective cohort studies. In most studies, there were patients diagnosed with mild-to-moderate COVID-19. In the included studies, bebtelovimab was administered intravenously. The studies that were included all had different sample patient sizes that ranged from 253 to 3872 patients with COVID-19, and they were all published in 2022.Table 1 Characteristics of included studies. Table 1Study Region Bebtelovimab No Bebtelovimab Study design Sample size Usage of Bebtelovimab Control group Patients included Agea Male (%) Agea Male (%) Dougan5 2022 America 37 62 (50) 34 56 (44) RCT 253 175 mg, intravenous injection Placebo Patients at low risk for severe COVID-19 Sridhara6 2022 America 64.0 (50.0,74.0) 469 (43.0) 64.0 (50.0,74.0) 474 (43.4) Retrospective cohort study 2182 175 mg, intravenous injection Standard of care Mild-to-moderate severe SARS-CoV-2 infection in adults who are at high-risk for progression to severe disease McCreary7 2022 America 61.2 ± 17.5 355 (38.2) 62.2 ± 18.3 359 (38.6) Retrospective cohort study 1860 175 mg, intravenous injection Standard of care COVID-19 who had at least 1 risk factor for progression to severe disease Dryden-Peterson8 2022 America NR 180 (47.7) NR 170 (45.1) Retrospective cohort study 754 175 mg, intravenous injection Standard of care Patients at high risk for progression to severe COVID-19 Razonable9 a 2022 America 66.7 (53.6–74.9) 1183 (41.8) 62.2 (49.5–73.8) 318 (41.4) Retrospective 3607 175 mg, intravenous injection Nirmatrelvir-ritonavir Mild to moderate COVID-19 Razonable10 b 2022 America 65.4 (49.9–74.0) 695 (41.1) 60.4 (40.8–70.8) 897 (41.1) Retrospective 3872 175 mg, intravenous injection Sotrovimab High-risk patients with mild to moderate COVID-19 Yetmar11 2022 America 59.7 (14.0) 55 (59.8) 56.9 (14.8) 167 (62.1) Retrospective cohort study 361 175 mg, intravenous injection Sotrovimab Adult solid organ transplant recipients diagnosed with mild-to-moderate COVID-19 a Age data presented as median (IQR) or mean (SD); RCT: randomized controlled trial; NR: not reported. The meta-analysis revealed that the bebtelovimab group was associated with a lower mortality rate than the group receiving standard of care (OR=0.11, 95%CI: 0.03–0.48, P = 0.003; I2 =0%) ( Fig. 1A). In addition, the bebtelovimab group and the standard of care group both had a similar risk of hospitalization (OR=0.77, 95%CI: 0.55–1.07, P = 0.12; I2 =0%) (Fig. 1B). There is no difference between the bebtelovimab group and other therapy groups in terms of mortality (OR=0.95, 95%CI: 0.38–2.35, P = 0.91; I2 =43%) (Fig. 1C) or ICU admission (OR=0.68, 95%CI: 0.36–1.28, P = 0.23; I2 =23%) (Fig. 1D).Fig. 1 (A) Comparison of mortality between the bebtelovimab group and the standard of care group. (B) Comparison of hospitalization between bebtelovimab group and standard of care group. (C) Comparison of mortality between bebtelovimab group and other therapy group. (D) Comparison of ICU admission between bebtelovimab group and other therapy group. Fig. 1 In this study, we find that the administration of bebtelovimab to patients with COVID-19 is associated with a significant reduction in mortality rate compared to patients receiving the standard of care, with no significant difference in hospitalization rates. Despite this mortality benefit, bebtelovimab use in patients with COVID-19 did not display superior outcomes compared to the positive drug controls of sotrovimab and nirmatrelvir-ritonavir (Paxlovid). The emergency use authorization of bebtelovimab was rapid given its remarkable efficacy against Omicron BA.5, the sublineage that aggressively spread in the Western Hemisphere at the end of 2022 given its spike-F486V mutation that was associated with neutralizing antibody resistance against other mAbs3, 12. While bebtelovimab’s mortality findings compared to standard of care treatment are positive, it did not appear to have any benefit to morbidity. However, the included studies tended to focus on patient populations with high-risk of progression to severe COVID-19 infection including presence of comorbidities such as solid organ transplant recipients. As such, given the included population was already vulnerable with elevated baseline risk factors as opposed to the general population, it appears the value of bebtelovimab is in particular preventing high-risk individuals with severe COVID-19 from progressing to death. This benefit appears to be conferred for high-risk individuals with both mild and moderate COVID-19 infection. The lack of inferiority of bebtelovimab compared to the positive drug controls allows it to be considered as another therapeutic modality if patients experience treatment failure. Further investigation is needed to assess if there are morbidity and mortality benefits of bebtelovimab treatment in low-risk patients. This is of particular importance given that previously robust neutralizing mAbs have shown diminishing effectiveness against COVID-1913. As COVID-19 continues to evolve, primary concerns have been focused on the BQ.1 and BQ.1.1 sublineages of the Omicron BA.5 variant, both exhibiting R346T and K444T mutations which facilitate increased antibody evasion directed at the spike protein4. In particular, bebtelovimab was found to be inactive against the BQ.1 and BQ.1.1 sublineages, resulting in its emergency use authorization being removed4. While all of our included studies analyzed patient populations between the Omicron BA.1 to BA.5 waves, none of them included the sublineages of the Omicron BA.5 variant. It is clear that with the dramatic genetic sequence changes between the earlier Omicron sublineages and its newer counterparts, additional studies including the predominant circulating strains are required to better inform choices in treatment. There remains unclear understanding on if there is a synergistic benefit between bebtelovimab and COVID-19 immunization. While vaccination alone has shown benefits in both morbidity and mortality in particular for patients with greater co-morbidities, the included studies had limited analysis between bebtelovimab and immunization14. Each study had slightly varying definitions of full vaccination and only two studies contained stratified results between vaccinated and unvaccinated individuals5, 6. With new sublineages displaying increased immune escape properties and resistance to targeted therapies developed against COVID-19, there continues to be a need to identify the most robust approaches at preventing COVID-19 disease morbidity and mortality. Our findings should be interpreted with consideration of the study's limitations. The meta-analysis had a relatively small sample size of seven included studies, with only three to four studies available for each sub-analysis on mortality, hospitalization, and ICU admission. In addition, there was variation in the study populations, in particular with COVID-19 vaccination status and presence of underlying comorbidities. It is possible there was a brief period of overlap in the bebtelovimab group of the two studies by Razonable et al., however, each study compared bebtelovimab to a different control. Furthermore, while the studies all focused on sublineages of the Omicron variant of concern, they did not include more recent and prevalent forms of Omicron including BQ.1 and BQ.1.1, which have been reported to have expanding immune escape properties4. Despite these limitations, our study is the first meta-analysis in the literature to explore the associations between bebtelovimab treatment and outcomes of patients with COVID-19. In conclusion, the use of bebtelovimab in patients with COVID-19 infection is associated with a significant reduction in mortality as compared to standard of care. A larger study sample size is needed to corroborate these findings. Further research is needed to better understand the impact of bebtelovimab with the predominant circulating variants of concern and through varying levels of severity of COVID-19 infection. Declaration of Competing Interest The authors declare that they have no competing interest. Acknowledgements This study was supported by Xinglin Scholars Program of 10.13039/501100008402 Chengdu University of Traditional Chinese Medicine (Grant number: YYZX2022033). ==== Refs References 1 Hsu W.H. Shiau B.W. Tsai Y.W. The effect of molnupiravir on post-acute outcome of COVID-19 survivor J Infect S0163–4453 23 2023 00145 00147 10.1016/j.jinf.2023.03.016 [published online ahead of print, 2023 Mar 21] 2 Yamasoba D. Kosugi Y. Kimura I. Neutralisation sensitivity of SARS-CoV-2 omicron subvariants to therapeutic monoclonal antibodies Lancet Infect Dis 22 7 2022 942 943 10.1016/S1473-3099(22)00365-6 35690075 3 Westendorf K. Žentelis S. Wang L. LY-CoV1404 (bebtelovimab) potently neutralizes SARS-CoV-2 variants Cell Rep 39 7 2022 110812 10.1016/j.celrep.2022.110812 4 Wang Q. Iketani S. Li Z. Alarming antibody evasion properties of rising SARS-CoV-2 BQ and XBB subvariants Cell 186 2 2023 279 286 10.1016/j.cell.2022.12.018 e8 36580913 5 Dougan M. Azizad M. Chen P. Bebtelovimab, alone or together with bamlanivimab and etesevimab, as a broadly neutralizing monoclonal antibody treatment for mild to moderate, ambulatory COVID-19 medRxiv 2022 10.1101/2022.03.10.22272100 6 Sridhara S. Gungor A.B. Erol H.K. Lack of effectiveness of bebtelovimab monoclonal antibody among high-risk patients with SARS-Cov-2 Omicron during BA.2, BA.2.12.1 and BA.5 subvariants dominated era medRxiv 2022 10.1101/2022.12.06.22283183 7 McCreary E.K. Kip K.E. Collins K. Evaluation of bebtelovimab for treatment of Covid-19 during the SARS-CoV-2 Omicron variant era Open Forum Infect Dis 9 10 2022 ofac517 10.1093/ofid/ofac517 Published 2022 Oct 1 8 Dryden-Peterson S. Kim A. Joyce M.R. Bebtelovimab for high-risk outpatients with early COVID-19 in a large US health system Open Forum Infect Dis 9 11 2022 ofac565 10.1093/ofid/ofac565 Published 2022 Oct 27 36438619 9 Razonable R.R. O'Horo J.C. Hanson S.N. Comparable outcomes for bebtelovimab and ritonavir-boosted nirmatrelvir treatment in high-risk patients with coronavirus disease-2019 during severe acute respiratory syndrome coronavirus 2 BA.2 Omicron epoch J Infect Dis 226 10 2022 1683 1687 10.1093/infdis/jiac346 36124696 10 Razonable R.R. Tulledge-Scheitel S.M. Hanson S.N. Real-world clinical outcomes of bebtelovimab and sotrovimab treatment of high-risk persons with coronavirus disease 2019 during the Omicron epoch Open Forum Infect Dis 9 10 2022 ofac411 10.1093/ofid/ofac411 Published 2022 Oct 6 36213724 11 Yetmar Z.A. Beam E. O'Horo J.C. Outcomes of bebtelovimab and sotrovimab treatment of solid organ transplant recipients with mild-to-moderate coronavirus disease 2019 during the Omicron epoch Transpl Infect Dis 24 4 2022 e13901 10.1111/tid.13901 12 Li A. Yung A. Tran C. Boulet M. SARS-CoV-2 Omicron BA.5: riding the seventh wave in central Canada Influenza Other Respir Virus 16 6 2022 1202 1204 10.1111/irv.13046 13 Ao G. Li A. Wang Y. Tran C. Qi X. Lack of efficacy for sotrovimab use in patients with COVID-19: a meta-analysis J Infect 85 1 2022 e10 e12 10.1016/j.jinf.2022.04.027 35461909 14 Ao G. Li A. Wang Y. Tran C. Gao M. Chen M. The effect of SARS-CoV-2 double vaccination on the outcomes of hemodialysis patients with COVID-19: a meta-analysis J Infect 86 2 2023 e43 e45 10.1016/j.jinf.2022.09.022 36174838
PMC010xxxxxx/PMC10122871.txt	==== Front CJEM CJEM Cjem 1481-8035 1481-8043 Springer International Publishing Cham 37087712 505 10.1007/s43678-023-00505-2 Brief Original Research Qualitative analysis of values and motivation reported by families utilizing a paediatric virtual care emergency clinic launched during the SARS-CoV-2 pandemic Sanderson Victoria 1 Vujcic Branka 2 Coulson Sherry 13 http://orcid.org/0000-0002-7157-4963 Lim Rodrick [email protected] 123 1 grid.39381.30 0000 0004 1936 8884 Department of Paediatrics, Schulich School of Medicine and Dentistry, Western University, London, ON Canada 2 grid.412745.1 0000 0000 9132 1600 Division of Emergency Medicine, London Health Sciences Centre, London, ON Canada 3 grid.413953.9 0000 0004 5906 3102 Children’s Health Research Institute, London, ON Canada 23 4 2023 2023 25 6 529533 20 10 2022 28 3 2023 © The Author(s), under exclusive licence to Canadian Association of Emergency Physicians (CAEP)/ Association Canadienne de Médecine d'Urgence (ACMU) 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic. Purpose This is the first study to take an in-depth qualitative approach to identify motivating factors for caregivers who chose the paediatric emergency virtual care option in Canada during the SARS-CoV-2 pandemic. The role that virtual care may play moving forward is also considered. Methods Between May 2020 and May 2021, 773 respondents attending the virtual clinic completed a follow-up survey with open-ended questions. For qualitative content analysis, comments were coded and analysed until thematic saturation was reached. Sub-codes were subsumed into major coding categories to identify themes. Results Three major themes, including safety, reassurance and convenience, and an overarching theme of satisfaction emerged from this analysis. Paediatric virtual clinic use was motivated in part by a desire to avoid the hospital environment. In-person Emergency Department visits were reported to be challenging and stressful, particularly due to perceived infection risk. Respondents appreciated that the clinic provided reassurance by assisting in navigating the healthcare system during a time of uncertainty and felt the virtual option allowed them to use healthcare resources responsibly. The convenience and ease of access to virtual care allowed for improved family-centred care in vulnerable populations. The overarching theme of satisfaction was emphasized by numerous comments for this service to be offered post-pandemic. Conclusion Our study indicates that virtual care was an attractive option for caregivers due to the safety, reassurance, and convenience provided. The strong patient desire for continued availability post-pandemic will be important considerations in this rapidly developing area of care. Supplementary Information The online version contains supplementary material available at 10.1007/s43678-023-00505-2. Résumé Objectif Il s'agit de la première étude à adopter une approche qualitative approfondie pour identifier les facteurs de motivation des aidants qui ont choisi l'option des soins virtuels d'urgence pédiatrique au Canada pendant la pandémie de SRAS-CoV-2. Le rôle que les soins virtuels pourraient jouer à l'avenir est également envisagé. Méthodes Entre mai 2020 et mai 2021, 773 personnes ayant participé à la clinique virtuelle ont répondu à une enquête de suivi comportant des questions ouvertes. Pour l'analyse qualitative du contenu, les commentaires ont été codés et analysés jusqu'à ce que la saturation thématique soit atteinte. Les sous-codes ont été subsumés en grandes catégories de codage afin d'identifier les thèmes. Résultats Trois thèmes principaux, à savoir la sécurité, le réconfort et la commodité, ainsi qu'un thème général de satisfaction ont émergé de cette analyse. L'utilisation de la clinique virtuelle pédiatrique a été motivée en partie par le désir d'éviter l'environnement hospitalier. Les visites en personne dans les services d'urgence ont été jugées difficiles et stressantes, notamment en raison du risque d'infection perçu. Les personnes interrogées ont apprécié que la clinique les rassure en les aidant à s'orienter dans le système de santé pendant une période d'incertitude et ont estimé que l'option virtuelle leur permettait d'utiliser les ressources de santé de manière responsable. La commodité et la facilité d'accès aux soins virtuels ont permis d'améliorer les soins centrés sur la famille dans les populations vulnérables. Le thème général de la satisfaction a été souligné par de nombreux commentaires pour que ce service soit offert après la pandémie. Conclusion Notre étude indique que les soins virtuels sont une option attrayante pour les aidants en raison de la sécurité, du réconfort et de la commodité qu'ils procurent. Le désir profond des patients de continuer à bénéficier de ces services après la pandémie sera un élément important à prendre en compte dans ce domaine de soins qui se développe rapidement. Keywords Paediatrics Virtual care Emergency medicine Content analysis Mots-clés Pédiatrie Soins virtuels Médecine d'urgence Analyse de contenu issue-copyright-statement© Canadian Association of Emergency Physicians (CAEP)/ Association Canadienne de Médecine d'Urgence (ACMU) 2023 ==== Body pmcClinician’s capsule What is known about the topic? Satisfaction with virtual care in Canada is high but the reasons for this satisfaction have yet to be elucidated. What did this study ask? Why are families choosing a virtual paediatric urgent care option in Canada and what impact is this service having? What did this study find? Families identified convenience, reassurance, and safety as the primary drivers of their satisfaction with the virtual option. Why does this study matter to clinicians? This study identifies patient values and opportunities for improvement to paediatric emergency care on an individual and policy level. Introduction Virtual care is defined as “any interaction between patients and/or members of their circle of care, occurring remotely, using any forms of communication or information technologies, with the aim of facilitating or maximizing the quality and effectiveness of patient care” [1]. Virtual care has had a limited role in Canadian paediatric emergency care to-date and primarily consisted of provider-to-provider interactions via phone prior to its more widespread implementation. In response to a 58% decrease in paediatric ED visits during the early COVID-19 pandemic [2], a virtual paediatric emergency care option was implemented at London Health Sciences Centre (LHSC). With virtual care systems now in place, studies of why families decide to utilize virtual emergency care are needed to understand the value to specific populations, and ultimately determine the role of virtual emergency paediatric care in Canada moving forward. The primary objective of this work was to identify the motivations for use and value of the paediatric emergency virtual clinic by analysing common themes identified within the responses of patients and families who have used the service. Methods Study design This qualitative content analysis was designed based on the technology acceptance model [3]. Data was collected from patients and their families who attended the virtual clinic through Children’s Hospital, LHSC. This was organized as a joint initiative of administration, physicians, information technology and risk management [4]. Continuous feedback of technological and patient/provider experience challenges were incorporated. With the initiation of the provincial programme, standards set out by the province were instituted, as were data reporting requirements. To attend the virtual clinic, parents or guardians initiate contact through the urgent care Ontario website and request an appointment to see a paediatrician. Appointments are slotted into empty time slots on a first come first served basis. Time slots are assigned at 15 min increments. The appointment included a “self-view” video feed to the physician for visual assessments as well as audio communication via WebEx, a secure virtual conferencing platform. At the time of registration, participants consented to a follow-up survey by the triage nurse. All patients registered were sent an exit survey link regardless of completion of visit. This allowed the broadest strategy to welcome criticism or support of the visit. This study was a quality improvement initiative as determined by the Western Research QI checklist and therefore this project was exempted from ethics approval in accordance with Article 2.5 of the TCPS. Study setting, time period and sample size Data was collected from a prospective cohort of all patients that were offered the exit survey following their virtual care visit. The cohort attended the virtual emergency clinic at LHSC Children’s Hospital between May 2020 and May 2021. Of 2194 total visits 773 virtual clinic patients responded to the survey (Supplemental 1). A brief anonymous survey was distributed to consenting families directly following their virtual ED visit. Two open-ended questions were asked in the survey: Please tell us, in your own words, the impact this virtual visit had for you today; and Is there anything else that you would like to share about how Children’s Hospital at LHSC can support patients and their loved ones during this time? Anonymized data was extracted into excel format for subsequent software uploading. The demographic data presented in Supplemental 2 was collected for 2194 VC patients from May 2020 to May 2021. The registration clerk consented each patient and asked for reason for choosing virtual care and contact with primary care provider prior to the appointment. Reason for visit, outcome, postal codes and age were obtained from the electronic health record. Data analysis Participant responses were analysed using conventional content analysis and the step model of inductive category development [5]. Survey responses were uploaded into Dedoose (Version 7.0.23) [6]. Respondent comments were independently coded by two reviewers (VS, BV) and analysed until thematic saturation was reached. The coding categories were then collaboratively assessed by reviewers (VS, BV, SC, RL) to ensure codes reliably and accurately captured the themes present within the patient responses. Any discrepancies or disagreements in coding were resolved through consensus. The codes were then applied to the remainder of the responses. Upon coding completion, related codes were combined and subcodes were subsumed within major coding categories to distinguish overarching, major and minor themes. Results The exit survey reached a 35.2% response rate (Supplemental 1), encompassing the full range of paediatric ages with a skew toward younger patients, a variety of clinical presentations, and both urban and rural patients from across the entire Southwestern Ontario catchment area and beyond. Demographic details, as well as reason for visit, presenting complaint and visit outcome are outlined in Supplemental 2. Qualitative content analysis and coding successfully identified commonalities among patient experiences. As demonstrated schematically in Fig. 1, the predominant theme was satisfaction. Major themes included reassurance, convenience, avoiding hospital environment and sustainability of programme further details outlined in Fig. 1 and Supplemental 3.Fig. 1 Schematic representation of breakdown of overarching, major and minor themes of satisfaction identified through qualitative analysis of responses from patients and families attending paediatric emergency virtual clinic The primary overarching theme of satisfaction with the virtual clinic dominated the patient narrative in this analysis with over 400 comments. Sub-themes of satisfaction included: usefulness of virtual care as a concept, thankful for this service during the pandemic included alleviating the stress of having an ill or susceptible family member, hesitancies of attending the hospital and obtaining guidance on pandemic related rules and restrictions from the virtual care team, as well as satisfaction with the physicians and staff. Over 200 responses were coded with comments relating to their desire to have this service as an option in the future post-pandemic. There were 80 comments coded with a negative experience or recommendations: 28 complaints (12 technology related, 8 associated with in-person care after virtual visit) and 64 recommendations (17 for expanded hours/expand to adults, 12 recommendations for the in-person ED/LHSC). Further details on sub-themes are described in Supplemental 3. Importantly, there were 4 comments regarding inclusivity, including: ensuring the use of inclusive language, providing an interpreter for deaf individuals, and improving access for blind parents. Discussion Interpretation of findings This study builds upon literature of virtual care in Canada by conducting a qualitative thematic analysis of the value and impact of paediatric virtual emergency services in the Canadian context. It provides new insight into the attractive features of a virtual care option for paediatric emergency patients. Those families who responded to the exit survey were satisfied by the convenience, reassurance, and ability to avoid the hospital environment. Comparison to previous studies The high level of satisfaction expressed by families represented in this study is mirrored in previous research, with 91% satisfaction rates in Canadian virtual care settings [7, 8]. On the other hand, drawbacks of virtual care have been well established in the literature including privacy concerns, lack of tactile physical examination, technical challenges, lack of access and treatment outcomes [9, 10; of which, only technical challenges were represented in the present study. Strengths and limitations The strengths of this research lie in the emphasis on family-centred care, as well as the qualitative methodological approach to analysis. This study is limited geographically to the LHSC Children’s virtual clinic and did not investigate impacts on in-person ED care. Additionally, these findings are specific to the COVID-19 time period,. There was a low response rate of 35% which limits the generalizability of these findings. Due to the self-selection for survey completion, there are likely important distinctions between respondents and non-respondents and it is possible non-respondents did not value the virtual care pathway. This study may have failed to capture individuals who were unable to access the virtual clinic. The survey was only available in English and thus language is a potential barrier to completion. This study did not aim to assess patient visit outcomes, quality of care or cost efficacy; however, these will be addressed in future studies. Clinical implications Virtual urgent care for paediatric populations is available in other geographic regions and based on patient satisfaction seems to be a logical next step in optimizing family-centred healthcare for this population, particularly in a geographically dispersed region like Canada. Research implications This study concludes that those who attended the virtual clinic and responded to the exit survey value the service and outlines why they chose it. There remain key gaps in knowledge relating to digital healthcare access, performance characteristics, health outcomes and economic evaluation in this setting. This study emphasizes the value of patient engagement and input to guide improvements to virtual care offerings. Conclusion Using qualitative content analysis of patient and caregiver experiences written in their own words, this study provides a picture of why families chose the virtual urgent care option. The primary finding of this paper is that virtual care in the paediatric setting helped many caregivers to navigate the healthcare system and avoid the hospital environment with a convenient option for care that left them feeling reassured and satisfied. Supplementary Information Below is the link to the electronic supplementary material.Supplementary file 1 (DOCX 33 KB) Funding None. Declarations Conflict of interest All authors declare that they have no conflict of interest. ==== Refs References: 1. Shaw J Jamieson T Agarwal P Griffin B Wong I Bhatia RS Virtual care policy recommendations for patient-centred primary care: findings of a consensus policy dialogue using a nominal group technique J Telemed Telecare 2018 24 9 608 615 10.1177/1357633X17730444 28945161 2. Finkelstein Y Maguire B Zemek R Osmanlliu E Kam AJ Dixon A Effect of the COVID-19 pandemic on patient volumes, acuity, and outcomes in pediatric emergency departments: a nationwide study Pediatr Emerg Care 2021 37 8 427 434 10.1097/PEC.0000000000002484 34074990 3. Wade V Gray L Carati C Theoretical frameworks in telemedicine research J Telemed Telecare 2017 23 1 181 187 10.1177/1357633X15626650 26787643 4. Rosenfield D Lim R Tse S Implementing virtual care in the emergency department: building on the pediatric experience during COVID-19 Can J Emerg Med 2021 23 1 15 18 10.1007/s43678-020-00026-2 5. Hsieh HF Shannon SE Three approaches to qualitative content analysis Qual Health Res 2005 15 9 1277 1288 10.1177/1049732305276687 16204405 6. Dedoose Version 7.0.23, web application for managing, analyzing and presenting qualitative and mixed method research data. Los Angeles, CA: Sociocultural Research Consultants, LLC; 2016. 7. Canadian Medical Association. What Canadians think about virtual health care: nationwide survey results. 2020;(May):1–30. 8. Goldbloom EB, Buba M, Bhatt M, Suntharalingam S, King WJ. Innovative virtual care delivery in a Canadian paediatric tertiary-care centre. Paediatr Child Health. 2022;27(Supplement_1):S9–14. 9. Brophy PD Overview on the challenges and benefits of using telehealth tools in a pediatric population Adv Chronic Kidney Dis 2017 24 1 17 21 10.1053/j.ackd.2016.12.003 28224938 10. Dorn SD. Backslide or forward progress? Virtual care at U.S. healthcare systems beyond the COVID-19 pandemic. NPJ Digit Med. 2021;4(1):1.
PMC010xxxxxx/PMC10124096.txt	==== Front J Infect J Infect The Journal of Infection 0163-4453 1532-2742 Published by Elsevier Ltd on behalf of The British Infection Association. S0163-4453(23)00249-9 10.1016/j.jinf.2023.04.015 Letter to the Editor Risk of severe outcomes among SARS-CoV-2 Omicron BA.4 and BA.5 cases compared to BA.2 cases in England Abdul Aziz Nurin ⁎1 Nash Sophie Grace 2 Zaidi Asad 3 UKHSA COVID-19 Vaccines and Epidemiology Division, UK Nyberg Tommy 4 MRC Biostatistics Unit, University of Cambridge, Cambridge, UK Groves Natalie 5 UKHSA Genomics and Public Health Analysis, UK Hope Russell 6 UKHSA HCAI, Fungal, AMR, AMU & Sepsis Division, UK Lopez Bernal Jamie 7 UKHSA COVID-19 Surveillance Cell, UK NIHR Health Protection Research Unit for Respiratory Infections, UK Dabrera Gavin 8 Thelwall Simon 910⁎ UKHSA COVID-19 Vaccines and Epidemiology Division, UK ⁎ Correspondence to: UKHSA, 61 Colindale Avenue, London NW9 5EQ, UK. ⁎ Correspondence to: UKHSA, 61 Colindale Avenue, London NW9 5EQ, UK. 1 https://orcid.org/0000-0002-8098-6935. 2 https://orcid.org/0000-0002-7717-6982. 3 https://orcid.org/0000-0002-6420-2539. 4 https://orcid.org/0000-0002-9436-0626. 5 https://orcid.org/0000-0002-3832-3484. 6 https://orcid.org/0000-0003-2838-6833. 7 https://orcid.org/0000-0002-1301-5653. 8 https://orcid.org/0000-0003-4606-5945. 9 https://orcid.org/0000-0002-0434-2724. 10 Senior author: UKHSA, 61 Colindale Avenue, London NW9 5EQ, UK. 24 4 2023 7 2023 24 4 2023 87 1 e8e11 21 4 2023 Crown Copyright © 2023 Published by Elsevier Ltd on behalf of The British Infection Association. All rights reserved. 2023 Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active. ==== Body pmcDear Editor, A recent study by Kang et al.1 found that individuals infected with the SARS-CoV-2 BA.5 Omicron sub-lineage exhibited more severe symptoms at the onset of symptomatic disease but had a shorter viable virus shedding period compared to individuals with BA.1 or BA.2. However, the study did not elucidate whether these differences reflected any variability in severe outcomes as the disease progressed. Additionally, data on BA.4 severity compared to previous sub-lineages are limited. Studies have shown that both BA.4 and BA.5 have a spike protein mutation with the potential for immune evasion,2 which may result in increased severity for BA.4 and BA.5 compared to previous sub-lineages. Herein, we used a case-control study to assess relative severity of BA.4 and BA.5 compared to BA.2 by estimating the differences in risk of severe outcomes following presentation to emergency care. While this has been undertaken in other countries with similar demographics, these studies have been conducted in settings with low vaccine coverage. The study included individuals with a PCR confirmed SARS-CoV-2 infection (COVID-19) in England between 1 April 2022 and 1 August 2022 inclusive, where linked whole genome sequencing (WGS) results were available confirming infection with the sub-lineages BA.2, BA.4, or BA.5, and who had attended an emergency department (ED) between one day before their positive test date and 14 days after their positive test date. Two case-control outcome definitions were considered. Outcome definition 1 included individuals whose ED attendance ended in hospital admission or transfer with a length of stay in hospital of 2 or more days; or whose ED attendance ended in death. They were compared with a control group of individuals whose ED attendance ended with discharge or a hospital admission of less than 2 days’ duration, and who did not die in the 2 days following ED attendance. Outcome definition 2 included COVID-19 patients who attended ED and received oxygen therapy. Controls were those who attended ED but did not receive oxygen therapy. This provided validation for definition 1 and a detailed metric for severity by using oxygen therapy as an indicator, as oxygen therapy has been frequently used in critical cases of COVID-19.3 Odds ratios (OR) of the outcomes and 95% confidence intervals (CI) were estimated using conditional logistic regression models. The models were stratified for week of positive test, and adjusted for age, sex, vaccination status, prior infection status, socioeconomic deprivation, region of residence, and ED attendances during the July extreme heat event. Further information on data acquisition and statistical analysis can be found in the supplementary document. A total of 23,023 individuals were included in the study. The number of BA.2, BA.4, and BA.5 patients included in the study reflected the temporal trends in overall COVID-19 test-positive incidence during the study period ( Fig. 1). 21,725 patients met the criteria to be included in the analysis according to outcome definition 1. Across all variants, those admitted or who died were more likely to be older. Higher proportions of BA.4 and BA.5 patients had received a spring booster or more than one booster, compared to BA.2 patients.Fig. 1 (A) Incidence of all confirmed COVID-19 Omicron BA.2, BA.4, and BA.5 in England between 1 April 2022 and 1 August 2022. (B) Incidence of individuals with BA.2, BA.4, and BA.5 included in the analysis by outcome status, according to outcome definition 1 where cases are individuals admitted ≥ 2 days or died within 2 days of attending ED and controls are individuals discharged from ED or admitted for< 2 days. Fig. 1 Using definition 1, the crude odds of admission or death after ED attendance for BA.4 (OR: 0.70; 95% CI: 0.63–0.77) and BA.5 (OR: 0.82; 95% CI: 0.77–0.86) were lower compared to BA.2 ( Table 1). However, after adjustment, the difference in the odds of admission or death was not statistically significant for either BA.4 (OR: 0.96; 95% CI: 0.86–1.08) or BA.5 (OR: 1.02; 95% CI: 0.93–1.12) compared to BA.2. For outcome definition 2, the OR estimates were similar but had wider confidence intervals due to a smaller sample size. Sensitivity analyses exploring alternative inclusion criteria, study periods, and outcome definitions provided consistent results (supplementary document).Table 1 Crude and adjusted odds ratios comparing risk of admission or death among individuals who attended A&E for COVID-19 cases with Omicron BA.4 and BA.5 compared to Omicron BA.2, by outcome definition. Data includes positive tests in England between April and August 2022. Table 1Case definition BA.4 versus BA.2 BA.5 versus BA.2 Crude Model Adjusted Stratified Model* Crude Model Adjusted Stratified Model OR (95% CI) P-value OR (95% CI) P-value OR (95% CI) P-value OR (95% CI) P-value Definition 1† 0.70 (0.63–0.77) < 0.0001 0.96 (0.86–1.08) 0.5297 0.82 (0.77–0.86) < 0.0001 1.02 (0.93–1.12) 0.7678 Definition 2‡ 0.76 (0.62–0.94) 0.0107 0.94 (0.70–1.28) 0.7118 0.89 (0.80 – 1.00) 0.0483 1.18 (0.92–1.52) 0.1847 * Model is a conditional logistic regression stratified by specimen test week, and adjusted for age group (10-year age bands), vaccination status, sex, prior infection status, and a flag for possible heatwave-related hospital attendances. † Definition 1: A case is any individual whose ED attendance ended in hospital admission with a length of stay in hospital of 2 or more days; if their ED attendance ended in death; or if they had a date of death up to 2 days after their initial date of ED attendance. A control is any individual whose ED attendance ended with discharge or a hospital admission of less than 2 days’ duration, and absence of death in the 2 days following ED attendance. ‡ Definition 2: A case is any individual who attended ED and received oxygen therapy in ED. A control is any individual who attended ED but did not receive oxygen therapy. Our results do not suggest a difference in the risk of hospital admission or death, or in oxygen supplementation, following presentation to ED for BA.4 or BA.5 patients compared to BA.2 patients. These results are consistent with evidence for minor differences in risk based on other cohorts of community tested COVID-19 patients.4, 5, 6 However, they differ from a community testing cohort in Denmark which found greater odds of hospitalisation for BA.5 compared to BA.2.7 The reasons for the discrepancies are unclear, and further research is warranted on the severity between Omicron sub-lineages in additional settings. COVID-19 testing policy in England changed on 01 April 2022, resulting in a reduction in testing overall and a change in the selection of specimens for WGS, which targets high-risk groups within the population.8 This meant that previous cohort approaches to estimate relative severity of SARS-CoV-2 variants9, 10 were no longer feasible. To resolve this problem, we conducted a case-control study of the risk of severe outcomes for those presenting to ED. Samples taken in hospital are preferentially sequenced; consequently, this population may reflect the subgroup of SARS-CoV-2-infected individuals at risk of hospital admission, as ED is the primary route by which people with severe COVID-19 would be admitted to hospital. However, this approach presents its own limitations. The probability of presenting to emergency care is a function of the severity of infection. Thus, people who are classified as controls are likely to be those for whom the infection is more severe than infections experienced in the general population. This restriction to COVID-19 patients with relatively severe disease regardless of variant might lead to biased estimates of relative risks compared to those that would be estimated if data derived from community mass testing were available. While recent dominant Omicron sub-lineages in England have shown no increase in severity relative to the previous dominant variant,9 it cannot be assumed that future lineages will continue this trend. Hence, continued surveillance of severe outcomes of novel SARS-CoV-2 variants is warranted. The methodology used in this study will be useful to monitor severity of COVID-19 among individuals who experience sufficiently severe disease to seek emergency care during periods with limited availability of testing; this will be vital to inform the public health response to future emerging variants. CRediT authorship contribution statement NA, ST and GD conceived and designed the study. NA prepared the datasets and performed the statistical analysis, supported by AZ and TN. NA, ST and SGN drafted the first version of the manuscript. All authors read, revised, and approved the final version of the manuscript. Data Availability The individual-level nature of the data used risks individuals being identified, or being able to self-identify, if the data are released publicly. Requests for access to these non-publicly available data should be directed to UKHSA. Ethics UKHSA has legal permission, provided by Regulation 3 of The Health Service (Control of Patient Information) Regulations 2002 to process confidential patient information under Section 3(i) (a)–(c), 3(i)(d) (i) and (ii) and 3(iii) as part of its outbreak response activities. This study falls within the research activities approved by the UKHSA Research Ethics and Governance Group. Funding This work was performed as part of UKHSA’s responsibility to monitor COVID-19 during the current pandemic. The work was supported by UK Research and Innovation (10.13039/100014013 UKRI ) Medical Research Council (10.13039/501100000265 MRC ) (TN: Unit Programme no. MC/UU/00002/11). Declaration of Competing Interest GD declares that his employer’s predecessor organisation, Public Health England, received funding from GlaxoSmithKline for a research project related to influenza antiviral treatment. This preceded and had no relation to COVID-19, and GD had no role in and received no funding from the project. All other authors report no potential conflicts. Appendix A Supplementary material Supplementary material Acknowledgments The authors acknowledge Anne Presanis and Daniela De Angelis from MRC Biostatistics Unit, University of Cambridge, for their expert advice. Appendix A Supplementary data associated with this article can be found in the online version at doi:10.1016/j.jinf.2023.04.015. ==== Refs References 1 Kang SW, Park H, Kim JY, Lim SY, Lee S, Bae JY, et al. Comparison of the clinical and virological characteristics of SARS-CoV-2 Omicron BA.1/BA.2 and omicron BA.5 variants: a prospective cohort study. J Infect [Internet]; 2023 Jan 16 [cited 2023 Mar 3]. Available from: 〈https://www.journalofinfection.com/article/S0163-4453(23)00020-8/fulltext〉. 2 Wang Q. Guo Y. Iketani S. Nair M.S. Li Z. Mohri H. Antibody evasion by SARS-CoV-2 Omicron subvariants BA.2.12.1, BA.4 and BA.5 Nature 608 7923 2022 603 608 35790190 3 Phua J. Weng L. Ling L. Egi M. Lim C.M. Divatia J.V. Intensive care management of coronavirus disease 2019 (COVID-19): challenges and recommendations Lancet Respir Med 8 5 2020 506 517 32272080 4 Davies MA, Morden E, Rosseau P, Arendse J, Bam JL, Boloko L, et al. Outcomes of laboratory-confirmed SARS-CoV-2 infection during resurgence driven by Omicron lineages BA.4 and BA.5 compared with previous waves in the Western Cape Province, South Africa. medRxiv; 2022, 2022.06.28.22276983. 5 Wolter N. Jassat W. Walaza S. Welch R. Moultrie H. Groome M.J. Clinical severity of SARS-CoV-2 Omicron BA.4 and BA.5 lineages compared to BA.1 and Delta in South Africa Nat Commun 13 1 2022 5860 36195617 6 Lewnard JA, Hong V, Kim JS, Shaw SF, Lewin B, Takhar H, et al. Association of SARS-CoV-2 BA.4/BA.5 Omicron lineages with immune escape and clinical outcome [Internet]. medRxiv; 2022 [cited 2022 Nov 11]. p. 2022.07.31.22278258. Available from: 〈https://www.medrxiv.org/content/10.1101/2022.07.31.22278258v2〉. 7 Hansen CH, Friis NU, Bager P, Stegger M, Fonager J, Fomsgaard A, et al. Risk of reinfection, vaccine protection, and severity of infection with the BA.5 omicron subvariant: a nation-wide population-based study in Denmark. Lancet Infect Dis [Internet]; 2022 [cited 2022 Nov 10]. Available from: 〈https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(22)00595-3/fulltext〉. 8 Halford F. Nash S. Tessier E. Kall M. Dabrera G. Variation in reported SARS-CoV-2 cases after testing policy changes Lancet Infect Dis 22 10 2022 1418 1419 36027903 9 Webster H.H. Nyberg T. Sinnathamby M.A. Aziz N.A. Ferguson N. Seghezzo G. Hospitalisation and mortality risk of SARS-COV-2 variant omicron sub-lineage BA.2 compared to BA.1 in England Nat Commun 13 1 2022 6053 36229438 10 Nyberg T. Ferguson N.M. Nash S.G. Webster H.H. Flaxman S. Andrews N. Comparative analysis of the risks of hospitalisation and death associated with SARS-CoV-2 omicron (B.1.1.529) and delta (B.1.617.2) variants in England: a cohort study Lancet 399 10332 2022 1303 1312 35305296

Subsets and Splits

No community queries yet

The top public SQL queries from the community will appear here once available.