Safety Culture Through Patient Voice: Qualitative Validation of the Patients' Perceptions of Safety Culture Scale (PaPSC) in Cardiology and Cardiothoracic Surgery
Introduction Patient involvement is a key but underutilized strategy to improving patient inpatient care. Depending on their health state, patients can actively contribute to their own safety . They are not merely passive recipients of treatment but also continues observers and active participants in the care process . Their unique perspective, combined with their constant presence, enables them to identify potential safety risks early and prevent potential errors. Health literacy studies have shown that patients can support safety interventions and monitor compliance. Through active participation, they can detect and highlight deviations, such as medication errors or procedural inconsistencies . However, many patients find it difficult to openly express safety‐related concerns or questions to healthcare professionals . This reluctance often stems from uncertainty about the role of the care team or a perceived power imbalance in the relationship with healthcare professionals, with time constraints and the perceived low effectiveness of patient engagement activities being key barriers . As a result, patients may hesitate to voice their observations or concerns when they recognize potential risks. Whether patients speak up about safety concerns or critical situations depends largely on the perceived safety culture within the healthcare setting . A positive safety culture fosters openness, transparency and trust and emphasizes that the safety of everyone, patients and staff, is a priority. Developing such a culture is therefore essential for improving patient safety. The importance of including the patient perspective in safety culture assessments is also emphasized in international patient safety initiatives. The WHO Global Action Plan for Patient Safety 2021‐2030 underscores the role of patients and families as active partners in enhancing safety (strategic goal 4) . Safety culture is a subset of the broader organizational culture and encompasses shared values, norms and beliefs that prioritize patient safety as a core objective . Key dimensions include communication, leadership, a blame‐free environment, safety systems, teamwork and workload management . However, these dimensions have predominantly been defined from the perspective of healthcare professionals, while the patient perspective in safety culture assessment has largely been overlooked. The Patients' Perceptions of Safety Culture Scale (PaPSC) was the first instrument specifically designed to systematically capture the patient perspective on safety culture . In the initial study, this 11‐item scale was administered in an online survey of more than 112,000 individuals with health insurance. Results indicated that respondents were generally able to answer the questions. However, due to limited information and unclear roles, patients had a different perspective on safety measures than healthcare professionals. Despite the high participation rates and good measurement properties of the scale, some critical questions remained unanswered . For example, it was unclear why patients could not rate safety measures in certain areas, leading to frequent ‘not applicable’ responses. One hypothesis is that this issue stems from the design of standardized instruments like the PaPSC, which prioritize simplicity and efficiency to facilitate swift and practical implementation. These characteristics make them particularly valuable in healthcare, as they facilitate comparability of results and seamless integration into different care contexts. However, standardization also presents challenges: Healthcare is inherently diverse, shaped by cultural, demographic and social factors, as well as variations in care settings . This diversity introduces many nuances that influence the patient experience but may not be fully captured by standardized items. In addition, external factors, such as interactions with healthcare staff, the care environment and patients' individual expectations, play a significant role in shaping their perceptions of safety and their interpretation of specific items. The condensed wording of such items risks overlooking or inadequately representing critical aspects of the patient‐centred perspective. This study aims to address these research gaps by qualitatively exploring patients' experiences of safety culture in healthcare . Also, the study explores the associations that patients make with specific items and examines which subjective experiences and perceptions are included or excluded. Furthermore, it assesses whether patients interpret the survey questions as intended or whether discrepancies exist between the original purpose of the scales and patients' actual perceptions. 

Methods This study was conducted in accordance with the Standards for Reporting Qualitative Research (SRQR) guidelines  and the Consolidated Criteria for Reporting Qualitative Research (COREQ) checklist . The application of qualitative research methods enabled a comprehensive exploration of patients' needs, perspectives and concerns. 2.1 Study Design This study employed a patient‐centred approach to validate the PaPSC using an exploratory, descriptive design with qualitative methods. To assess content validity, we used problem‐centred interviews that incorporated episodic techniques and concrete examples to illustrate individual patient experiences. This method follows a deductive–inductive approach, allowing for structured yet flexible data collection and analysis . The semi‐structured format enabled participants to freely discuss safety culture issues while maintaining focus . To gain deeper insight into patients' cognitive processes, we also used the Think‐Aloud method, which required participants to verbalize their thoughts while answering survey items. This approach helped identify misunderstandings, ambiguities and contextual associations. The Think‐Aloud approach complemented the semi‐structured interviews and provided real‐time data on how patients interpreted and processed survey questions . A semi‐structured interview guide ensured a coherent flow of information, based on the PaPSC items. Participants had the opportunity to ask questions and share positive and negative experiences. A combined deductive‐inductive approach structured the interviews while allowing unique insights to emerge . All interviews were conducted by the lead author (C.M.). After each interview, a postscript documented contextual factors, subjective insights and environmental influences . Participants could withdraw from the study at any time without providing a reason. To enhance internal validation, problem‐centred interviews ensured that the PaPSC items were both theoretically sound and practically understandable (Online Resource 1: Interview Guide). All interviews were audio‐recorded and transcribed in full. Sociodemographic data were collected using the Demographic Standards for Personal Oral and Written Survey forms. Direct questions (e.g., nationality) were asked, while for other variables (e.g., level of education, employment status), participants selected the most appropriate response from a predefined list of options . 2.2 Data Collection Participants were recruited over a 3‐month period (June to August 2021) from the general cardiology or cardiothoracic surgery wards of a maximum‐care university hospital in western North Rhine‐Westphalia, Germany. These wards provided optimal research setting due to the variety and complexity of procedures, potential risks of interventions and patients' in‐depth knowledge of hospital processes. A purposive sampling strategy was employed to maximize diversity in age, gender, diagnoses and treatment modalities (Table ). Patients were excluded if they did not meet the inclusion criteria, did not provide consent, were critically ill, or had cognitive impairments. To ensure data saturation, we aimed to recruit as many participants as necessary to capture a wide range of patient perspectives. Data saturation was defined as the point at which no new themes, concepts or variations emerged from additional interviews, indicating that further data collection would no longer yield meaningful new insights. At this stage, data collection was concluded. 2.3 Procedure and Sample Information Initial contact with potential interview participants was made during their inpatient stay on the general cardiology and cardiothoracic surgery wards. Following the morning ward round, nursing staff identified eligible patients and provided them with an information leaflet about the study and informed the lead author. The lead author then provided further details, explaining voluntary participation, data protection and study procedures. Patients were given sufficient time to consider their participation and discuss with the decision with their relatives. Interviews were conducted either in the patient's room or in a private area of the ward, depending on the patient's mobility and preference. Before each interview, the study aims and procedures were reiterated, and participants provided both written and audio‐recorded consent. 2.4 Ethical Considerations The ethical implications of the study were carefully considered during the planning and execution phases. The study was conducted in accordance with the principles of the Declaration of Helsinki and the European Data Protection Law. The process evaluation was approved by the Ethics Committee of the Medical Faculty of the University of Cologne (No. 20‐1490_1 on December 21, 2020). The study is registered in the German Clinical Trials Register (DRKS) under the DRKS ID: DRKS00022778. The DRKS has been designated as a WHO primary registry since October 2008. Data processing followed the legal principles set out in the General Data Protection Regulation . Following Mayer's  guidelines, interviews were conducted in a comfortable, undisturbed environment to ensure a respectful and open dialogue. Effective interview techniques included demonstrating genuine interest, avoiding multiple questions at once, and encouraging participants to share their thoughts freely. No invasive measures were used during the interviews; however, sensitive topics were discussed. To support participants, all patients were offered access to a psychologically trained counselling team. Discussing adverse events can provide relief, foster a sense of being heard, and contribute to a safer hospital environment. Patients may also find the interviews redemptive, viewing them as an opportunity to voice concerns and initiate change that will ultimately benefit future patients. In addition, the following ethical considerations were addressed: Voluntary participation: Patients were reminded that participation was voluntary and could be discontinued at any time without consequence. Confidentiality: If patients reported adverse events, they were encouraged to do so confidentially through the hospital's compliments and complaints system, with relevant contact information provided. Absolute confidentiality was assured by the interviewer. Protection of hospital staff: Measures were taken to ensure that ward teams were not sanctioned based on the study findings. COVID‐19 precautions: All relevant safety protocols were strictly followed. 2.5 Analysis The pseudonymized transcripts were analysed using MAXQDA Analytics Pro 2024 , a robust tool for transcribing and analysing qualitative data. Following the methodology of Kuckartz and Rädiker , a deductive‐inductive content analysis was conducted. Initially, the principal investigator immersed himself in the data, creating memos, summarizing case studies and integrating field notes. A preliminary deductive‐inductive category system was developed based on themes from the interview guide, PaPSC items, and an initial text analysis. All transcripts were analysed according to the interview questions outlined in the interview guide. For the PaPSC, individual questions were examined in detail, and subdimensions or categories assigned to each item to better capture the content‐related facets of the respective items. If shifts in thinking occurred during the interviews, the corresponding items were subsequently reassigned to ensure a coherent categorization of content. The coding process was overseen by C.M., with A.H. providing valuable input on refining the category system and interpreting interview excerpts. To ensure objectivity, we also sought feedback from an expert panel. Patient quotations, translated from German to English, are presented alongside pseudonyms to underscore the findings of this study. 2.6 Reflexivity and Reliability To ensure study quality, careful attention was given to credibility, transferability, reliability and confirmability. A comprehensive account of the study's objectives, context, recruitment and data analysis was provided . All interviews were conducted and transcribed by the same author (C.M.), which enhanced reliability, particularly in segments with audio challenges. The interdisciplinary approach enabled a rigorous examination of the findings and generated new insights. This collaboration strengthened the validity and reliability of the results. Following multiple rounds of discussion, the authors collectively determined the most reliable interpretation of the data while also considering alternative perspectives. 

Study Design This study employed a patient‐centred approach to validate the PaPSC using an exploratory, descriptive design with qualitative methods. To assess content validity, we used problem‐centred interviews that incorporated episodic techniques and concrete examples to illustrate individual patient experiences. This method follows a deductive–inductive approach, allowing for structured yet flexible data collection and analysis . The semi‐structured format enabled participants to freely discuss safety culture issues while maintaining focus . To gain deeper insight into patients' cognitive processes, we also used the Think‐Aloud method, which required participants to verbalize their thoughts while answering survey items. This approach helped identify misunderstandings, ambiguities and contextual associations. The Think‐Aloud approach complemented the semi‐structured interviews and provided real‐time data on how patients interpreted and processed survey questions . A semi‐structured interview guide ensured a coherent flow of information, based on the PaPSC items. Participants had the opportunity to ask questions and share positive and negative experiences. A combined deductive‐inductive approach structured the interviews while allowing unique insights to emerge . All interviews were conducted by the lead author (C.M.). After each interview, a postscript documented contextual factors, subjective insights and environmental influences . Participants could withdraw from the study at any time without providing a reason. To enhance internal validation, problem‐centred interviews ensured that the PaPSC items were both theoretically sound and practically understandable (Online Resource 1: Interview Guide). All interviews were audio‐recorded and transcribed in full. Sociodemographic data were collected using the Demographic Standards for Personal Oral and Written Survey forms. Direct questions (e.g., nationality) were asked, while for other variables (e.g., level of education, employment status), participants selected the most appropriate response from a predefined list of options . 

Data Collection Participants were recruited over a 3‐month period (June to August 2021) from the general cardiology or cardiothoracic surgery wards of a maximum‐care university hospital in western North Rhine‐Westphalia, Germany. These wards provided optimal research setting due to the variety and complexity of procedures, potential risks of interventions and patients' in‐depth knowledge of hospital processes. A purposive sampling strategy was employed to maximize diversity in age, gender, diagnoses and treatment modalities (Table ). Patients were excluded if they did not meet the inclusion criteria, did not provide consent, were critically ill, or had cognitive impairments. To ensure data saturation, we aimed to recruit as many participants as necessary to capture a wide range of patient perspectives. Data saturation was defined as the point at which no new themes, concepts or variations emerged from additional interviews, indicating that further data collection would no longer yield meaningful new insights. At this stage, data collection was concluded. 

Procedure and Sample Information Initial contact with potential interview participants was made during their inpatient stay on the general cardiology and cardiothoracic surgery wards. Following the morning ward round, nursing staff identified eligible patients and provided them with an information leaflet about the study and informed the lead author. The lead author then provided further details, explaining voluntary participation, data protection and study procedures. Patients were given sufficient time to consider their participation and discuss with the decision with their relatives. Interviews were conducted either in the patient's room or in a private area of the ward, depending on the patient's mobility and preference. Before each interview, the study aims and procedures were reiterated, and participants provided both written and audio‐recorded consent. 

Ethical Considerations The ethical implications of the study were carefully considered during the planning and execution phases. The study was conducted in accordance with the principles of the Declaration of Helsinki and the European Data Protection Law. The process evaluation was approved by the Ethics Committee of the Medical Faculty of the University of Cologne (No. 20‐1490_1 on December 21, 2020). The study is registered in the German Clinical Trials Register (DRKS) under the DRKS ID: DRKS00022778. The DRKS has been designated as a WHO primary registry since October 2008. Data processing followed the legal principles set out in the General Data Protection Regulation . Following Mayer's  guidelines, interviews were conducted in a comfortable, undisturbed environment to ensure a respectful and open dialogue. Effective interview techniques included demonstrating genuine interest, avoiding multiple questions at once, and encouraging participants to share their thoughts freely. No invasive measures were used during the interviews; however, sensitive topics were discussed. To support participants, all patients were offered access to a psychologically trained counselling team. Discussing adverse events can provide relief, foster a sense of being heard, and contribute to a safer hospital environment. Patients may also find the interviews redemptive, viewing them as an opportunity to voice concerns and initiate change that will ultimately benefit future patients. In addition, the following ethical considerations were addressed: Voluntary participation: Patients were reminded that participation was voluntary and could be discontinued at any time without consequence. Confidentiality: If patients reported adverse events, they were encouraged to do so confidentially through the hospital's compliments and complaints system, with relevant contact information provided. Absolute confidentiality was assured by the interviewer. Protection of hospital staff: Measures were taken to ensure that ward teams were not sanctioned based on the study findings. COVID‐19 precautions: All relevant safety protocols were strictly followed. 

Analysis The pseudonymized transcripts were analysed using MAXQDA Analytics Pro 2024 , a robust tool for transcribing and analysing qualitative data. Following the methodology of Kuckartz and Rädiker , a deductive‐inductive content analysis was conducted. Initially, the principal investigator immersed himself in the data, creating memos, summarizing case studies and integrating field notes. A preliminary deductive‐inductive category system was developed based on themes from the interview guide, PaPSC items, and an initial text analysis. All transcripts were analysed according to the interview questions outlined in the interview guide. For the PaPSC, individual questions were examined in detail, and subdimensions or categories assigned to each item to better capture the content‐related facets of the respective items. If shifts in thinking occurred during the interviews, the corresponding items were subsequently reassigned to ensure a coherent categorization of content. The coding process was overseen by C.M., with A.H. providing valuable input on refining the category system and interpreting interview excerpts. To ensure objectivity, we also sought feedback from an expert panel. Patient quotations, translated from German to English, are presented alongside pseudonyms to underscore the findings of this study. 

Reflexivity and Reliability To ensure study quality, careful attention was given to credibility, transferability, reliability and confirmability. A comprehensive account of the study's objectives, context, recruitment and data analysis was provided . All interviews were conducted and transcribed by the same author (C.M.), which enhanced reliability, particularly in segments with audio challenges. The interdisciplinary approach enabled a rigorous examination of the findings and generated new insights. This collaboration strengthened the validity and reliability of the results. Following multiple rounds of discussion, the authors collectively determined the most reliable interpretation of the data while also considering alternative perspectives. 

Results The results begin with descriptive analyses, providing an overview of participants' demographics and key characteristics to contextualize the findings. The study sample comprised 22 interviews, including 10 conducted in the cardiology ward and 12 in the cardiothoracic surgery ward. Data saturation was achieved after the 22 interviews, as no new findings emerged . 3.1 Sample Characterization The interview duration ranged from 16 to 102 min, with an average length of 47 min. The longest transcript contained 11.526 words (Table ). Table provides an overview of the sociodemographic characteristics of the 22 participants. The gender distribution shows that 13 participants (59%) were male, while 9 (41%) were female. The mean age of respondents fell predominantly between 50 and 79 years, with the 60–69 age group exhibiting the highest representation ( n = 8; 36%). Nearly all participants ( n = 20; 91%) were born in Germany and hold German citizenship. The majority of respondents were married ( n = 10; 46%) and resided in a two‐person household ( n = 12; 55%). In terms of professional qualifications, 13 (59%) completed vocational training, and the majority were already retired ( n = 11; 50%). Regarding monthly household income, the majority of respondents reported earnings between €1.000 and €4.000. 3.2 Safety Culture Coding Patterns and Key Patient Priorities The coding frequency of the interviews suggests that certain items were particularly well understood and represented key patient concerns. For example, the item ‘During the whole hospital stay, I felt I was in “safe hands.”’ was coded 242 times. Similarly, the item ‘I had the impression that patient safety was always a top priority’. was frequently mentioned, with 142 codes. In addition, 112 codes for ‘I always knew who was responsible for my treatment and care’ indicate that patients valued clarity regarding accountability in their care. In contrast, fewer codes were found for items such as ‘Staff freely spoke up whenever they had the impression that something was amiss’. (58 codes), ‘The information exchange between physicians and nurses. was very smooth’. (74 codes), and ‘The different services (ward, X‐ray, physiotherapy, etc.) are well coordinated’ (79 codes). Table presents the assigned codes and subcodes for each PaPSC item. In addition, it includes two patient quotations and a key message. The frequency of coding for each specific PaPSC item is also displayed. 3.3 Summary of Content Validation Process for the PaPSC Items This section summarizes the coding evaluation in relation to the PaPSC items, integrating central themes and key messages to illustrate patients' perceptions of safety and satisfaction during their hospital stay. The codes and subcodes were systematically organized into thematic categories to represent relevant aspects of safety culture from the patient's perspective at different organizational levels. 3.3.1 During the Whole Hospital Stay, I Felt I Was in ‘Safe Hands’ Many patients reported feeling well cared for during their hospitalization, particularly regarding effective pain management and the prompt responsiveness of staff. A sense of safety was closely linked to confidence in staff competence. However, long waiting times and a lack of transparency in information sharing led to feelings of uncertainty for some individuals. Effective communication and staff helpfulness were identified as key factors influencing patients' well‐being. 3.3.2 I Had the Impression That Patient Safety Was Always a Top Priority Patients frequently expressed a positive perception of safety during their hospitalization, largely due to the expertise and professional care provided by staff. Prompt responses to concerns and transparent communication in the event of errors further reinforce confidence in the hospital's safety culture. However, some respondents noted that staff shortages and the presence of inexperienced personnel could compromise safety. Additionally, it was emphasized that effective communication and individualized care play a crucial role in fostering a sense of safety among patients. 3.3.3 The Information Exchange Between Physicians and Nurses Was Very Smooth Patients had varying perceptions of the information exchange between physicians and nursing staff. While some commended the staff's competence and effective communication, which fostered a sense of security, others reported challenges, particularly language barriers and inadequate communication. Nevertheless, many emphasize the effective collaboration within the medical team, which contributed to improved coordination and quality of care. 3.3.4 The Physicians Were Well Informed About My History and Current Medical Condition and Treatment Patients reported mixed experiences regarding how well doctors were informed about their medical histories. While some felt well cared for, benefiting from an efficient exchange of medical records, others expressed concerns that physicians were not always well informed and frequently repeated the same questions. The use of digital resources was generally perceived as beneficial, though not consistently implemented. Patients emphasized that clear and understandable communication was essential for fostering trust in the quality of their care. 3.3.5 The Nurses Were Well Informed About My History and Current Medical Condition and Treatment Patients' perceptions of nurses' knowledge regarding their medical history and treatment varied. While some were satisfied with the level of information provided and the nurses' attentiveness, others raised concerns about gaps in communication. Some patients perceive digital resources and technical monitoring as beneficial for tracking their health status. The competence of nursing staff was partially assessed through their interactions and communication with patients. Several respondents expressed a desire for more detailed explanations and conversations about their treatment plans to enhance their perception of care. 3.3.6 After Handover (Shift Change, Transfer), Staff Knew All Relevant Information Necessary for My Care Following shift changes or handovers, patients typically reported a satisfactory exchange of information and a sense of security in the hands of their care providers. Recurring staff members were perceived as particularly reassuring. However, on rare occasions, minor details were inadvertently overlooked, causing distress, especially when patients' concerns were repeatedly expressed but not addressed. 3.3.7 Physicians and Nurses Worked Together as a Well‐Rehearsed Team The majority of patients expressed a positive opinion regarding the collaboration between medical practitioners and nursing staff. Many commended the collaborative and amicable teamwork, while some highlighted potential areas for improvement, particularly considering staff transitions and the presence of hierarchical structures. Effective communication and mutual trust were considered essential. However, language barriers and hierarchical differences were perceived as potential obstacles that could impact teamwork effectiveness. 3.3.8 The Different Services (Ward, X‐Ray, Physiotherapy, etc.) Are Well Coordinated Most patients perceived the coordination between different hospital department, such as the ward, X‐ray department and physiotherapy, is perceived by most patients to be well‐structured and effective. The implementation of organized procedures and smooth interdepartmental collaboration contributed to a positive treatment experience. However, some patients reported delays and confusion, particularly in cases involving external dependencies or insufficient communication between departments. Waiting times, in particular, were identified as a concern, highlighting the need for improvements in scheduling and coordination. 3.3.9 I Always Knew Who Was Responsible for My Treatment and Care A number of patients reported a high level of confidence in the hospital and its processes, which they felt contributed to their well‐being. The consistency of procedures and clear organizational structure reinforced this trust, as patients perceived that everything was functioning effectively. Clarity regarding responsibilities and effective communication with staff were identified as particularly important factors. Patients expressed gratitude for the transparent delegation of responsibility within the healthcare team, commending the unwavering dedication of medical professionals. However, some patients experienced uncertainty, particularly due to frequent staff changes and unclear responsibilities, which led to confusion. 3.3.10 Staff Freely Spoke up Whenever They Had the Impression That Something Was Amiss Patients reported varied experiences regarding the openness of staff in addressing problems. Some respondents commended the proactive approach taken by nursing staff, which reinforced their trust in the care provided. An open and transparent communication style was perceived as particularly positive, especially when mistakes were acknowledged with sincerity, Fostering a sense of security. However, some patients expressed frustration over a perceived lack of transparency and clarity in communication, which they felt contributed to uncertainty. In general, fostering open communication increased trust in the care and treatment provided. 3.3.11 There Was Always Enough Qualified Staff Available Overall, most patients expressed positive sentiments regarding the quality of care they received. However, some questioned staff qualifications, particularly when inexperienced personnel lacked adequate guidance or when existing staff were overworked. While some patients expressed confidence in staff competence and felt well cared for. Others were concerned about the deployment of inexperienced personnel in challenging situations without sufficient support. Although the overall feedback was predominantly positive; the balance between experienced an inexperienced staff was occasionally criticized. 3.4 Thematic Summary of Codes and Subcodes This section builds on the initial identification of codes and subcodes to present a systematic summary and thematic organization. The aim of this approach is to identify the key factors shaping safety culture from the patient's perspective across different organizational levels. Aligning the codes within a structured framework allows for a holistic analysis of both patient‐centred and organizational aspects. Figure provides a visual representation of the categories developed at the All Levels, the Organizational Level, the Clinical Level and the Patient Level. 

Sample Characterization The interview duration ranged from 16 to 102 min, with an average length of 47 min. The longest transcript contained 11.526 words (Table ). Table provides an overview of the sociodemographic characteristics of the 22 participants. The gender distribution shows that 13 participants (59%) were male, while 9 (41%) were female. The mean age of respondents fell predominantly between 50 and 79 years, with the 60–69 age group exhibiting the highest representation ( n = 8; 36%). Nearly all participants ( n = 20; 91%) were born in Germany and hold German citizenship. The majority of respondents were married ( n = 10; 46%) and resided in a two‐person household ( n = 12; 55%). In terms of professional qualifications, 13 (59%) completed vocational training, and the majority were already retired ( n = 11; 50%). Regarding monthly household income, the majority of respondents reported earnings between €1.000 and €4.000. 

Safety Culture Coding Patterns and Key Patient Priorities The coding frequency of the interviews suggests that certain items were particularly well understood and represented key patient concerns. For example, the item ‘During the whole hospital stay, I felt I was in “safe hands.”’ was coded 242 times. Similarly, the item ‘I had the impression that patient safety was always a top priority’. was frequently mentioned, with 142 codes. In addition, 112 codes for ‘I always knew who was responsible for my treatment and care’ indicate that patients valued clarity regarding accountability in their care. In contrast, fewer codes were found for items such as ‘Staff freely spoke up whenever they had the impression that something was amiss’. (58 codes), ‘The information exchange between physicians and nurses. was very smooth’. (74 codes), and ‘The different services (ward, X‐ray, physiotherapy, etc.) are well coordinated’ (79 codes). Table presents the assigned codes and subcodes for each PaPSC item. In addition, it includes two patient quotations and a key message. The frequency of coding for each specific PaPSC item is also displayed. 

Summary of Content Validation Process for the PaPSC Items This section summarizes the coding evaluation in relation to the PaPSC items, integrating central themes and key messages to illustrate patients' perceptions of safety and satisfaction during their hospital stay. The codes and subcodes were systematically organized into thematic categories to represent relevant aspects of safety culture from the patient's perspective at different organizational levels. 3.3.1 During the Whole Hospital Stay, I Felt I Was in ‘Safe Hands’ Many patients reported feeling well cared for during their hospitalization, particularly regarding effective pain management and the prompt responsiveness of staff. A sense of safety was closely linked to confidence in staff competence. However, long waiting times and a lack of transparency in information sharing led to feelings of uncertainty for some individuals. Effective communication and staff helpfulness were identified as key factors influencing patients' well‐being. 3.3.2 I Had the Impression That Patient Safety Was Always a Top Priority Patients frequently expressed a positive perception of safety during their hospitalization, largely due to the expertise and professional care provided by staff. Prompt responses to concerns and transparent communication in the event of errors further reinforce confidence in the hospital's safety culture. However, some respondents noted that staff shortages and the presence of inexperienced personnel could compromise safety. Additionally, it was emphasized that effective communication and individualized care play a crucial role in fostering a sense of safety among patients. 3.3.3 The Information Exchange Between Physicians and Nurses Was Very Smooth Patients had varying perceptions of the information exchange between physicians and nursing staff. While some commended the staff's competence and effective communication, which fostered a sense of security, others reported challenges, particularly language barriers and inadequate communication. Nevertheless, many emphasize the effective collaboration within the medical team, which contributed to improved coordination and quality of care. 3.3.4 The Physicians Were Well Informed About My History and Current Medical Condition and Treatment Patients reported mixed experiences regarding how well doctors were informed about their medical histories. While some felt well cared for, benefiting from an efficient exchange of medical records, others expressed concerns that physicians were not always well informed and frequently repeated the same questions. The use of digital resources was generally perceived as beneficial, though not consistently implemented. Patients emphasized that clear and understandable communication was essential for fostering trust in the quality of their care. 3.3.5 The Nurses Were Well Informed About My History and Current Medical Condition and Treatment Patients' perceptions of nurses' knowledge regarding their medical history and treatment varied. While some were satisfied with the level of information provided and the nurses' attentiveness, others raised concerns about gaps in communication. Some patients perceive digital resources and technical monitoring as beneficial for tracking their health status. The competence of nursing staff was partially assessed through their interactions and communication with patients. Several respondents expressed a desire for more detailed explanations and conversations about their treatment plans to enhance their perception of care. 3.3.6 After Handover (Shift Change, Transfer), Staff Knew All Relevant Information Necessary for My Care Following shift changes or handovers, patients typically reported a satisfactory exchange of information and a sense of security in the hands of their care providers. Recurring staff members were perceived as particularly reassuring. However, on rare occasions, minor details were inadvertently overlooked, causing distress, especially when patients' concerns were repeatedly expressed but not addressed. 3.3.7 Physicians and Nurses Worked Together as a Well‐Rehearsed Team The majority of patients expressed a positive opinion regarding the collaboration between medical practitioners and nursing staff. Many commended the collaborative and amicable teamwork, while some highlighted potential areas for improvement, particularly considering staff transitions and the presence of hierarchical structures. Effective communication and mutual trust were considered essential. However, language barriers and hierarchical differences were perceived as potential obstacles that could impact teamwork effectiveness. 3.3.8 The Different Services (Ward, X‐Ray, Physiotherapy, etc.) Are Well Coordinated Most patients perceived the coordination between different hospital department, such as the ward, X‐ray department and physiotherapy, is perceived by most patients to be well‐structured and effective. The implementation of organized procedures and smooth interdepartmental collaboration contributed to a positive treatment experience. However, some patients reported delays and confusion, particularly in cases involving external dependencies or insufficient communication between departments. Waiting times, in particular, were identified as a concern, highlighting the need for improvements in scheduling and coordination. 3.3.9 I Always Knew Who Was Responsible for My Treatment and Care A number of patients reported a high level of confidence in the hospital and its processes, which they felt contributed to their well‐being. The consistency of procedures and clear organizational structure reinforced this trust, as patients perceived that everything was functioning effectively. Clarity regarding responsibilities and effective communication with staff were identified as particularly important factors. Patients expressed gratitude for the transparent delegation of responsibility within the healthcare team, commending the unwavering dedication of medical professionals. However, some patients experienced uncertainty, particularly due to frequent staff changes and unclear responsibilities, which led to confusion. 3.3.10 Staff Freely Spoke up Whenever They Had the Impression That Something Was Amiss Patients reported varied experiences regarding the openness of staff in addressing problems. Some respondents commended the proactive approach taken by nursing staff, which reinforced their trust in the care provided. An open and transparent communication style was perceived as particularly positive, especially when mistakes were acknowledged with sincerity, Fostering a sense of security. However, some patients expressed frustration over a perceived lack of transparency and clarity in communication, which they felt contributed to uncertainty. In general, fostering open communication increased trust in the care and treatment provided. 3.3.11 There Was Always Enough Qualified Staff Available Overall, most patients expressed positive sentiments regarding the quality of care they received. However, some questioned staff qualifications, particularly when inexperienced personnel lacked adequate guidance or when existing staff were overworked. While some patients expressed confidence in staff competence and felt well cared for. Others were concerned about the deployment of inexperienced personnel in challenging situations without sufficient support. Although the overall feedback was predominantly positive; the balance between experienced an inexperienced staff was occasionally criticized. 

During the Whole Hospital Stay, I Felt I Was in ‘Safe Hands’ Many patients reported feeling well cared for during their hospitalization, particularly regarding effective pain management and the prompt responsiveness of staff. A sense of safety was closely linked to confidence in staff competence. However, long waiting times and a lack of transparency in information sharing led to feelings of uncertainty for some individuals. Effective communication and staff helpfulness were identified as key factors influencing patients' well‐being. 

I Had the Impression That Patient Safety Was Always a Top Priority Patients frequently expressed a positive perception of safety during their hospitalization, largely due to the expertise and professional care provided by staff. Prompt responses to concerns and transparent communication in the event of errors further reinforce confidence in the hospital's safety culture. However, some respondents noted that staff shortages and the presence of inexperienced personnel could compromise safety. Additionally, it was emphasized that effective communication and individualized care play a crucial role in fostering a sense of safety among patients. 

The Information Exchange Between Physicians and Nurses Was Very Smooth Patients had varying perceptions of the information exchange between physicians and nursing staff. While some commended the staff's competence and effective communication, which fostered a sense of security, others reported challenges, particularly language barriers and inadequate communication. Nevertheless, many emphasize the effective collaboration within the medical team, which contributed to improved coordination and quality of care. 

The Physicians Were Well Informed About My History and Current Medical Condition and Treatment Patients reported mixed experiences regarding how well doctors were informed about their medical histories. While some felt well cared for, benefiting from an efficient exchange of medical records, others expressed concerns that physicians were not always well informed and frequently repeated the same questions. The use of digital resources was generally perceived as beneficial, though not consistently implemented. Patients emphasized that clear and understandable communication was essential for fostering trust in the quality of their care. 

The Nurses Were Well Informed About My History and Current Medical Condition and Treatment Patients' perceptions of nurses' knowledge regarding their medical history and treatment varied. While some were satisfied with the level of information provided and the nurses' attentiveness, others raised concerns about gaps in communication. Some patients perceive digital resources and technical monitoring as beneficial for tracking their health status. The competence of nursing staff was partially assessed through their interactions and communication with patients. Several respondents expressed a desire for more detailed explanations and conversations about their treatment plans to enhance their perception of care. 

After Handover (Shift Change, Transfer), Staff Knew All Relevant Information Necessary for My Care Following shift changes or handovers, patients typically reported a satisfactory exchange of information and a sense of security in the hands of their care providers. Recurring staff members were perceived as particularly reassuring. However, on rare occasions, minor details were inadvertently overlooked, causing distress, especially when patients' concerns were repeatedly expressed but not addressed. 

Physicians and Nurses Worked Together as a Well‐Rehearsed Team The majority of patients expressed a positive opinion regarding the collaboration between medical practitioners and nursing staff. Many commended the collaborative and amicable teamwork, while some highlighted potential areas for improvement, particularly considering staff transitions and the presence of hierarchical structures. Effective communication and mutual trust were considered essential. However, language barriers and hierarchical differences were perceived as potential obstacles that could impact teamwork effectiveness. 

The Different Services (Ward, X‐Ray, Physiotherapy, etc.) Are Well Coordinated Most patients perceived the coordination between different hospital department, such as the ward, X‐ray department and physiotherapy, is perceived by most patients to be well‐structured and effective. The implementation of organized procedures and smooth interdepartmental collaboration contributed to a positive treatment experience. However, some patients reported delays and confusion, particularly in cases involving external dependencies or insufficient communication between departments. Waiting times, in particular, were identified as a concern, highlighting the need for improvements in scheduling and coordination. 

I Always Knew Who Was Responsible for My Treatment and Care A number of patients reported a high level of confidence in the hospital and its processes, which they felt contributed to their well‐being. The consistency of procedures and clear organizational structure reinforced this trust, as patients perceived that everything was functioning effectively. Clarity regarding responsibilities and effective communication with staff were identified as particularly important factors. Patients expressed gratitude for the transparent delegation of responsibility within the healthcare team, commending the unwavering dedication of medical professionals. However, some patients experienced uncertainty, particularly due to frequent staff changes and unclear responsibilities, which led to confusion. 

Staff Freely Spoke up Whenever They Had the Impression That Something Was Amiss Patients reported varied experiences regarding the openness of staff in addressing problems. Some respondents commended the proactive approach taken by nursing staff, which reinforced their trust in the care provided. An open and transparent communication style was perceived as particularly positive, especially when mistakes were acknowledged with sincerity, Fostering a sense of security. However, some patients expressed frustration over a perceived lack of transparency and clarity in communication, which they felt contributed to uncertainty. In general, fostering open communication increased trust in the care and treatment provided. 

There Was Always Enough Qualified Staff Available Overall, most patients expressed positive sentiments regarding the quality of care they received. However, some questioned staff qualifications, particularly when inexperienced personnel lacked adequate guidance or when existing staff were overworked. While some patients expressed confidence in staff competence and felt well cared for. Others were concerned about the deployment of inexperienced personnel in challenging situations without sufficient support. Although the overall feedback was predominantly positive; the balance between experienced an inexperienced staff was occasionally criticized. 

Thematic Summary of Codes and Subcodes This section builds on the initial identification of codes and subcodes to present a systematic summary and thematic organization. The aim of this approach is to identify the key factors shaping safety culture from the patient's perspective across different organizational levels. Aligning the codes within a structured framework allows for a holistic analysis of both patient‐centred and organizational aspects. Figure provides a visual representation of the categories developed at the All Levels, the Organizational Level, the Clinical Level and the Patient Level. 

Discussion The PaPSC is an innovative approach that systematically integrates the patient perspective into safety culture assessment. Standardized instruments like the PaPSC are valuable for measuring and comparing safety culture across care settings , However, they often fail to fully capture the complexity of patient experiences in healthcare . The healthcare system is inherently characterized by numerous individual nuances that cannot be fully addressed by standardized survey items . Additionally, applying these instruments to diverse patient groups and varied care settings poses a significant challenge . To enhance the quality and validity of such instruments, a thorough understanding of the patient's perspective is essential . Combining standardized scales with qualitative methods can reveal the ‘invisible dimensions’ behind survey items, thereby refining measurement tools and promoting patient‐centred improvements in healthcare . The evaluation and comparison of the quantitative and qualitative results identified several research gaps, including why certain aspects of patient safety culture are difficult to assess . The findings indicate that each PaPSC item represents underlying subdimensions of safety culture. Consequently, additional explanatory text was developed to explicitly include these subdimensions, thereby improving the comprehensibility and applicability of the scale across different patient groups (see Online Resource 2 for the additional explanatory text). For example, the item ‘During the whole hospital stay, I felt I was in “safe hands”’. was coded 242 times, suggesting its importance to many patients. The item with the highest level of agreement in the pilot study was 84,9%. The high coding frequency and strong agreement rate suggest that patients consistently felt reassured and confident in the care they received, emphasizing the importance of trust and safety during their hospital stay. In contrast, the item with the fewest codes was ‘Staff freely spoke up whenever they had the impression that something was amiss’ (58 codings) and also received the highest percentage of ‘not applicable’ responses (25.7%) in the pilot study . This finding suggests that many patients found it difficult to evaluate or comment on this aspect of their care experience. Another key finding is the identification of ‘semantic fields’ underlying specific survey items, reflecting how patients interpret the same item differently based on their experiences, expectations and context . For example, while one patient may associate ‘safe hands’ as emotional support and empathy, another may interpret it with procedural accuracy or technical competence . These findings underscore the need to account for such variation to refine and improve survey instruments. The identification of ‘semantic fields’ also highlights the sender‐receiver dynamic between patients and healthcare professionals . Patients respond based on their subjective experiences, whereas healthcare professionals interpret these responses through a clinical lens. These differing perspectives can result in misinterpretations, potentially leading to inaccurate conclusions or missed opportunities for improvement. To bridge this gap, explanatory materials and training are essential to enhance healthcare professionals' understanding of the patient perspective. Such materials can serve as interpretive guides, ensuring that patient responses are contextualized and effectively inform quality improvement efforts. Several strengths emerge from this study. First, it is among the first to systematically integrate the patient perspective into safety culture assessment using a validated tool. By combining standardized and qualitative approaches, we explored not only how patients respond to safety culture items, but also why they interpret them in certain ways . This methodological triangulation enhances the validity and applicability of the PaPSC. Second, problem‐centred interviews and the Think‐Aloud method actively involved patients in refining the comprehensibility and contextual relevance of the scale. Potential misinterpretations were minimized and usability across different patient groups was improved. Finally, our findings underscore the importance of patient‐centred safety culture assessments that consider both ‐ technical and relational dimensions of safety . Patients tend to prioritize interpersonal aspects and trust in healthcare professionals over procedural factors . Consistent with previous research trust in healthcare professionals has been shown to have a significant impact on perceived safety and patient satisfaction . The identified codes and sub‐codes are closely in line with findings from other safety culture and patient safety studies . However, it is important to acknowledge that some studies have also identified negative aspects of active patient involvement, such as patients feeling overwhelmed . These findings emphasize the need to view patient involvement not merely as an ideal but as a complex process that includes both positive and potentially burdensome aspects . The PaPSC is a valuable tool for the systematic assessment of patient safety culture from the patient's perspective. Our findings suggest that the applicability and validity of the instrument in different healthcare settings could be further enhanced through targeted refinements. By incorporating qualitative insights into standardized assessments, future studies can improve the accuracy and interpretability of safety culture measures . Integrating the patient perspective into standardized instruments remains a key challenge, particularly when considering diverse patient groups and care contexts. Future safety culture research should further examine how different patient demographics influence perceptions of safety and whether tailored wording of survey questions could reduce variability in responses . Another important focus should be on minimizing communication barriers between patients and healthcare professionals. This includes training programmes to raise staff awareness of the importance of patient involvement and the development of strategies that encourage patients to openly share their observations and concerns . 

Limitations This study has several limitations regarding its scope and generalizability. First, the sample was restricted to cardiology and cardiothoracic surgery patients from a single hospital. Institutional factors may have influenced the findings, limiting their applicability to other hospitals or healthcare settings. Additionally, as the interviews were conducted within a fixed study period, the results reflect a specific point in time, without capturing longitudinal changes in perceptions of safety culture. Moreover, the sample may not fully represent diverse patient groups in terms of age, cultural background or chronic conditions. Another limitation is that patients were not directly involved in the study design, as the primary aim was to validate an existing instrument rather than develop a new one. The decision to use a predefined scale was based on previous research, in which relevant survey items had already been identified. However, involving patients earlier in the development phase could have further enhanced the instrument's applicability to patients' real‐life experiences. Qualitative research has inherent limitations, including the potential for interpretation bias, particularly since all interviews were conducted by a single researcher. Despite measures to increase reliability, subjectivity cannot be completely eliminated. While data saturation is a widely accepted concept, it remains somewhat subjective and depends on the diversity of the sample, the research objectives and the depth of analysis. Although it is defined as the point at which no new themes emerge, it does not guarantee that all perspectives have been fully captured. In studies with diverse patient experiences, some nuances may persist. We closely monitored emerging themes and ensured a diverse sample, but limiting the study to two departments may have influenced the point at which saturation was reached. Additionally, as the study focused primarily on the PaPSC, other relevant aspects of patient safety culture may have been overlooked. 

Conclusion This study advances our understanding of patients' perceptions of safety culture by identifying key dimensions that influence how patients evaluate safety in healthcare settings. By integrating qualitative methods with a standardized measurement tool (PaPSC), we explored not only how patients respond to safety culture items, but also why they interpret them in particular ways. The findings highlight the importance of ensuring that such tools accurately capture the diversity and complexity of patient experiences, rather than reducing them to numerical scores. A key finding is that interpersonal aspects—such as trust, communication and empathy—are central to perceptions of patient safety. While standardized instruments provide valuable benchmarking opportunities, they should be continuously refined to reflect both procedural safety measures and the relational dynamics that affect patient well‐being. Moreover, this study supports global patient safety initiatives, particularly the WHO Global Action Plan for Patient Safety 2021–2030 (Strategic Goal 4), which emphasizes the active involvement of patients and families in safety improvement efforts . The findings highlight the value of qualitative approaches in filling gaps in standardized assessments and ensuring that safety culture measures are more patient‐centred and context‐sensitive. To build on these findings, future research should expand data collection to include more hospitals and specialties to examine how patient safety culture differs between institutions. In addition, longitudinal studies could provide insights into how perceptions of safety culture evolve over time and in response to healthcare interventions. By incorporating these findings into future research and practice, healthcare systems can improve the validity of safety culture assessments, strengthen patient‐centred safety strategies and promote a more inclusive and transparent safety culture. This study serves as a foundation for advancing holistic, mixed‐methods frameworks that combine qualitative depth with quantitative rigour to improve patient safety outcomes globally. 

Clara Monaca: conceptualization, methodology, software, validation, formal analysis, investigation, resources, data curation, writing ‐ original draft, writing ‐ review and editing, visualization, project administration, funding acquisition. Matthias Weigl: methodology, writing ‐ review and editing, supervision. Holger Pfaff: methodology, writing ‐ review and editing, supervision. Antje Hammer: conceptualization, methodology, validation, formal analysis, investigation, writing ‐ review and editing, supervision. 

Approved by the Ethics Committee of the Medical Faculty of the University of Cologne (No. 20‐1490_1 of December 21, 2020). The study was registered in the German Clinical Trials Register (DRKS) under DRKS ID: DRKS00022778. 

All participants provided their explicit consent for the anonymized publication of their data. They were informed that their responses would be used in academic publications and were assured that no personally identifiable information would be disclosed. All participants provided informed consent before being included in the study. They were informed of the purpose, methods and implications of the research and were assured of their right to withdraw at any time without consequence. Participants' confidentialities and anonymity were maintained throughout the research process. 

The authors declare no conflicts of interest. 

Supporting information. Supporting information. 

