***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background A commonly reported problem with the conduct of multicentre r and omised controlled trials ( RCTs ) is that recruitment is often slower or more difficult than expected , with many trials failing to reach their planned sample size within the timescale and funding originally envisaged . The aim of this study was to explore factors that may have been associated with good and poor recruitment in a cohort of multicentre trials funded by two public bodies : the UK Medical Research Council ( MRC ) and the Health Technology Assessment ( HTA ) Programme . Methods The cohort of trials was identified from the administrative data bases held by the two funding bodies . 114 trials that recruited participants between 1994 and 2002 met the inclusion criteria . The full scientific applications and subsequent trial reports su bmi tted by the trial teams to the funders provided the principal data sources . Associations between trial characteristics and recruitment success were tested using the Chi-squared test , or Fisher 's exact test where appropriate . Results Less than a third ( 31 % ) of the trials achieved their original recruitment target and half ( 53 % ) were awarded an extension . The proportion achieving targets did not appear to improve over time . The overall start to recruitment was delayed in 47 ( 41 % ) trials and early recruitment problems were identified in 77 ( 63 % ) trials . The inter-relationship between trial features and recruitment success was complex . A variety of strategies were employed to try to increase recruitment , but their success could not be assessed . Conclusion Recruitment problems are complex and challenging . Many of the trials in the cohort experienced recruitment difficulties . Trials often required extended recruitment periods ( sometimes supported by additional funds ) . While this is of continuing concern , success in addressing the trial question may be more important than recruitment alone Objectives To assess : 1 ) the feasibility of electronic information provision ; 2 ) gather evidence on the topics and level of detail of information potential research participant ’s accessed ; 3 ) to assess satisfaction and underst and ing . Design Observational study with an embedded r and omised controlled trial . Setting Low risk intervention study based in primary care . Participants White British & Irish , South Asian and African-Caribbean subjects aged between 40 - 74 years eligible for a blood pressure monitoring study . Interventions PDF copy of the st and ard paper participant information sheet ( PDF-PIS ) and an electronic Interactive Information Sheet ( IIS ) where participants could choose both the type and level of detail accessed . Main Outcome Measures 1 ) Proportion of participants providing an email address and accessing electronic information 2 ) Willingness to participate in a recruitment clinic . 3 ) Type and depth of information accessed on the IIS . 4 ) Participant satisfaction and underst and ing . Results 1160 participants were eligible for the study . Of these , 276 ( 24 % ) provided an active email address , of whom 84 did not respond to the email . 106 responded to the email but chose not to access any electronic information and were therefore ineligible for r and omisation . 42 were r and omised to receive the PDF-PIS and 44 to receive the IIS ( with consent rates of 48 % and 36 % , respectively ; odds ratio 0.6 , 95 % confidence interval 0.25 to 1.4 ) . Electronic observation of information accessed by potential participants showed 41 % chose to access no information and only 9 % accessed the detail presented on the Research Ethics Committee approved participant information sheet before booking to attend a recruitment clinic for the intervention study . 63 of the 106 participants ( 59 % ) who chose not to access any electronic information also booked an appointment . Conclusions Current written information about research may not be read , emphasising the importance of the consent interview and consideration of new ways of presenting complex information Background We present the design , methods and population characteristics of a large community trial that assessed the efficacy of a weekly supplement containing vitamin A or beta-carotene , at recommended dietary levels , in reducing maternal mortality from early gestation through 12 weeks postpartum . We identify challenges faced and report solutions in implementing an intervention trial under low-re source , rural conditions , including the importance of population choice in promoting generalizability , maintaining rigorous data quality control to reduce inter- and intra- worker variation , and optimizing efficiencies in information and re sources flow from and to the field . Methods This trial was a double-masked , cluster-r and omized , dual intervention , placebo-controlled trial in a contiguous rural area of ~435 sq km with a population of ~650,000 in Gaib and ha and Rangpur Districts of Northwestern Bangladesh . Approximately 120,000 married women of reproductive age underwent 5-weekly home surveillance , of whom ~60,000 were detected as pregnant , enrolled into the trial and gave birth to ~44,000 live-born infants . Upon enrollment , at ~ 9 weeks ' gestation , pregnant women received a weekly oral supplement containing vitamin A ( 7000 ug retinol equivalents ( RE ) ) , beta-carotene ( 42 mg , or ~7000 ug RE ) or a placebo through 12 weeks postpartum , according to prior r and omized allocation of their cluster of residence . Systems described include enlistment and 5-weekly home surveillance for pregnancy based on menstrual history and urine testing , weekly supervised supplementation , periodic risk factor interviews , maternal and infant vital outcome monitoring , birth defect surveillance and clinical /biochemical sub studies . Results The primary outcome was pregnancy-related mortality assessed for 3 months following parturition . Secondary outcomes included fetal loss due to miscarriage or stillbirth , infant mortality under three months of age , maternal obstetric and infectious morbidity , infant infectious morbidity , maternal and infant micronutrient status , fetal and infant growth and prematurity , external birth defects and postnatal infant growth to 3 months of age . Conclusion Aspects of study site selection and its " resonance " with national and rural qualities of Bangladesh , the trial 's design , methods and allocation group comparability achieved by r and omization , field procedures and innovative approaches to solving challenges in trial conduct are described and discussed . This trial is registered with http:// Clinical trials.gov as protocol NCT00198822 In the Physicians ' Health Study , a r and omized , placebo-controlled , double-blind trial of aspirin in the reduction of cardiovascular mortality and beta-carotene in decreasing cancer incidence , 33,223 subjects were eligible and willing to enter the trial . Instead of r and omizing this group immediately , all participants received identical calendar packs that contained active aspirin and beta-carotene placebo . Following an 18-week run-in , only 22,071 subjects who remained eligible and willing and had taken at least 2/3 of their pills were r and omized . We estimated the effect of the run-in as follows : pill taking compliance increased 20 - 41 per cent ; sample size decreased 34 per cent ; duration of follow-up decreased 7 per cent which result ed in a 7 per cent decrease in the expected event rate for the placebo group . To estimate these changes , we made assumptions about compliance and outcome risk for those excluded by the run-in . Our conclusion , however , about the net effect of the run-in on the power of the study remains constant across variations in a number of those assumptions . The power with the run-in , with 22,071 good compliers was typically higher , and never more than negligibly lower , than the power without the run-in , with 33,223 good and poor compliers . In addition , savings from enrolling 11,152 fewer subjects in the trial result ed from the use of the run-in This r and omized study was design ed to assess the utility of an educational video in preparing cancer patients for decisions about clinical trial participation . The study assessed the effect of the video  on patients ' underst and ing and perceptions of clinical trials , its impact on decision making and patient‐provider communication , and patients ' satisfaction with the video Background Physical activity is being studied as a breast cancer prevention strategy . Women at risk of breast cancer report interest in lifestyle modification , but recruitment to r and omized physical activity intervention studies is challenging . Methods We conducted an analysis of recruitment techniques used for a prospect i ve , r and omized pilot study of physical activity in women at risk of breast cancer . We evaluated differences in proportion of eligible patients , enrolled patients , and successful patients identified by each individual recruitment method . The Fisher-Freeman-Halton test ( an extension of Fisher 's exact test from 2 × 2 tables to general row by column tables ) was used to compare the success of different recruitment strategies . Results We received 352 inquiries from women interested in participating , of whom 171 ( 54 % ) were eligible . Ninety-nine women completed a baseline activity evaluation , and 58 ( 34 % of eligible ; 16 % of total inquiries ) were r and omized . Recruitment methods fell into three broad categories : media techniques , direct contact with potential participants , and contacts with health care providers . Recruitment strategies differed significantly in their ability to identify eligible women ( p = 0.01 ) , and women who subsequently enrolled in the study ( p = 0.02 ) . Conclusion Recruitment techniques had varying success . Our data illustrate the challenges in recruiting to behavior modification studies , and provide useful information for tailoring future recruitment efforts for lifestyle intervention trials . Trial Registration No(s)CDR0000393790 , NCI-04-C-0276 , NCI-NAVY-B05 - Using data from a r and omized , controlled feeding study , which aim ed to recruit 88 participants ( including 22 Hispanics and 22 African Americans ) , we examined strategies for recruiting individuals from underrepresented groups into research trials . Study eligibility criteria included participants who 1 ) were 18 - 45 years old ; 2 ) had a body mass index ( BMI ) > 18<24.9 or BMI > 28.0 < 40.0 ; 3 ) ; had no preexisting health conditions ; 4 ) were non-smoking ; 5 ) had normal fasting blood glucose level ( < 100 mg/dL ) ; and 6 ) spoke English . Participants were recruited using two overarching methods : media-based strategies ( flyers and posters , email announcements , announcements in local and campus newspapers , and the Internet ) and in-person strategies ( presentations in university classes and community events ) . Participants were enrolled March 2006-March 2009 . We present the numbers of individuals requesting study information , completing pre-enrollment screening question naires , and enrolling in the study . A total of 1036 individuals requested study information , and 396 completed a pre-enrollment screening question naire ; 90 enrolled in the study ( 22 Hispanics and 18 African Americans ) . Among enrolled participants , in-person recruitment strategies were reported by 39 % of African Americans , 73 % of Hispanics , and 30 % of non-Hispanic Whites ( P<0.001 ) . In-person recruitment strategies were successful among Hispanics . Mass media recruitment strategies were successful among non-Hispanic Whites but enlisted relatively few Hispanic participants . Both strategies recruited nearly equal percentages of African Americans . These data suggest that different strategies are needed to effectively recruit racial/ethnic population subgroups into intervention studies Objectives : To determine the effects of risk and payment on  subjects ’ willingness to participate  , and to examine how payment influences subjects ’ potential behaviours and risk evaluations . Methods : A 3 ( level of risk ) × 3 ( level of monetary payment ) , between subjects , completely r and omised factorial design was used . Students enrolled at one of five US pharmacy schools read a recruitment notice and informed consent form for a hypothetical study , and completed a question naire . Risk level was manipulated using recruitment notices and informed consent documents from hypothetical biomedical research projects . Payment levels were determined using the payment models evaluated by Dickert and Grady as a guide . Five dependent variables were assessed in the question naire : willingness to participate , willingness to participate with no payment , propensity to neglect to tell about restricted activities , propensity to neglect to tell about negative effects , and risk rating . Results : Monetary payment had positive effects on respondents ’ willingness to participate in research , regardless of the level of risk . However , higher monetary payments did not appear to blind respondents to the risks of a study . Payment had some influence on respondents ’ potential behaviours regarding concealing information about restricted activities . However , payment did not appear to have a significant effect on respondents ’ propensity to neglect to tell research ers about negative effects . Conclusions : Monetary payments appear to do what they are intended to do : make subjects more willing to participate in research . Concerns about payments blinding subjects to risks could not be substantiated in the present study . However , the findings do raise other concerns — notably the potential for payments to diminish the integrity of a study ’s findings . Future research is critical to make sound decisions about the payment of research subjects OBJECTIVES We hypothesized that knowing the regulations regarding emergency research without consent would increase public support for this type of research . METHODS R and omized controlled trial . Consecutive patients presenting during eight 24-h periods received one of two interviews ; the intervention interview included an educational paragraph . RESULTS There were 473 ( 74 % of eligible ) patients who participated : 51 % ( 95 % confidence interval [ CI ] 46 - 55 ) were willing to be enrolled in a study using exception to informed consent ; 84 % ( 95 % CI 80 - 87 ) believed that current therapy for cardiac arrest offers ≥ 50 % chance of full recovery , and these patients were less willing to enroll ( odds ratio [ OR ] 0.5 , 95 % CI 0.3 - 0.9 ) . The educational intervention increased willingness to enroll ( OR 1.3 
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Only 3 of 72 comparisons are supported by high-certainty evidence according to GRADE : having an open trial and using telephone reminders to non-responders to postal interventions both increase recruitment ; a specialised way of developing participant information leaflets had little or no effect .