***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 OBJECTIVE To examine pediatricians ' attitudes toward children 's participation in r and omized controlled trials ( RCTs )  and identify possible barriers to participation . STUDY DESIGN Qualitative analysis of focus group discussion s involving 16 pediatricians and 5 trainees from a pediatric teaching hospital in Australia . Doctors varied in occupation , experience , research activity , age , sex , ethnicity , and parenthood experience . A professional facilitator conducted the semistructured group discussion s. The transcribed audiotapes were analyzed by theme linkage by using the constant comparative method . RESULTS Pediatricians believed parents balanced perceived gains and risks when deciding about trial participation . They thought the child 's condition , parents ' health beliefs and personal attributes , and the doctors ' beliefs and relationship with the investigators influenced parents ' attitudes . Perceived gains included professional benefits for pediatricians , improved patient care , convenience for the families and themselves , and scientific advancement . Perceived risks included inconvenience , inadequate re sources , and potential harms to the patient and doctor-patient relationship . Pediatricians with previous research experience were most knowledgeable about RCTs and perceived greatest gains from trial participation . Pediatricians ' personal treatment preferences hindered trial support . CONCLUSIONS This study suggests that children 's participation in trials will be enhanced by increasing pediatricians ' awareness of RCTs through education and involvement in trials and by improving the gains-risk balance Background One of the most commonly reported problems of r and omised trials is that recruitment is usually slower than expected . Trials will cost more and take longer , thus delaying the use of the results in clinical practice , and incomplete sample s imply decreased statistical power and usefulness of its results . We aim to identify barriers and facilitators for successful patient recruitment at the level of the patient , the doctor and the hospital organization as well as the organization and design of trials over a broad range of studies . Methods / design We will perform two cohort studies and a case-control study in the Netherl and s. The first cohort study will report on a series of multicenter trials performed in a nationwide network of clinical trials in obstetrics and gynaecology . A question naire will be sent to all clinicians recruiting for these trials to identify determinants - aggregated at centre level - for the recruitment rate . In a case control- study nested in this cohort we will interview  patients who refused or consented participation to identify factors associated with patients ' consent or refusal . In a second cohort study , we will study trials that were prospect ively registered in the Netherl and s Trial Register . Using a question naire survey we will assess whether issues on hospital organization , trial organization , planning and trial design were associated with successful recruitment , i.e. 80 % of the predefined number of patients recruited within the planned time . Discussion This study will provide insight in barriers and facilitators for successful patient recruitment in trials . The results will be used to provide recommendations and a checklist for individual trialists to identify potential pitfalls for recruitment and judge the feasibility prior to the start of the study . Identified barriers and motivators coupled to evidence -based interventions can improve recruitment of patients in clinical trials Background Qualitative methods are increasingly used to study the process of clinical trials and patients underst and ing of the rationale for trials , r and omisation and reasons for taking part or refusing . Patients ' underst and ings are inevitably influenced by the recruiting clinician 's underst and ing of the trial , yet relatively little qualitative work has explored clinicians ' perceptions and underst and ings of trials . This study interviewed surgeons shortly after the multi-centre , pragmatic RCT in which they had participated had been completed . Methods We used in-depth interviews with surgeons who participated in the Spine Stabilisation Trial ( a pragmatic RCT ) to explore their underst and ing of the trial purpose and how this underst and ing had influenced their recruitment procedures and interpretation of the results . A purposive sample of eleven participating surgeons was chosen from 8 of the 15 UK trial centres . Results Although the surgeons thought that the trial was addressing an important question there was little agreement about what this question was : although it was a trial of ' equivalent ' treatments , some thought that it was a trial of surgery , others a trial of rehabilitation and others that it was exploring what to do with patients in whom all other treatment options had been unsuccessful . The surgeons we interviewed were not aware of the rationale for the pragmatic inclusion criteria and nearly all were completely baffled about the meaning of ' equipoise ' . Misunderst and ings about the entry criteria were an important source of confusion about the results and led to reluctance to apply the results to their own practice . Conclusion The study suggests several lessons for the conduct of future multi-centre trials . Recruiting surgeons ( and other clinicians ) may not be familiar with the rationale for pragmatic design s and may need to be regularly reminded about the purpose during the study . Reassurance may be necessary that a pragmatic design is not considered a design fault . We conclude that it does matter if clinicians do not underst and the rationale for the trial if , as we have shown here , their perception of the trial aims and methods adversely affects who they recruit ; if their views affect what the patients are told ; and if they mistakenly view the results as unscientific , unreliable and ultimately irrelevant to their practice Background Under-recruitment to r and omised controlled trials ( RCTs ) is often problematic and there may be particular difficulties in recruiting patients with severe mental illness . Aim To evaluate reasons for under-recruitment in an RCT of patients with severe mental illness Methods Qualitative study during the recruitment phase of an RCT of supported employment . Trial staff and recruiting clinicians were interviewed . Data were analyzed thematically using constant comparative techniques . Results Recruitment rates were low . Five main reasons for recruitment difficulties were found . These included : ( i ) misconceptions about trials , ( ii ) lack of equipoise , ( iii ) misunderst and ing of the trial arms , ( iv ) variable interpretations of eligibility criteria , ( v ) paternalism . Conclusion Reasons for recruitment difficulties in trials involving patients with severe mental illness include issues that occur in trials in general , but others are more specific to these patients . Clinician and patient involvement in the study design may improve recruitment in future similar trials Background Poor recruitment and retention of participants in r and omised controlled trials ( RCTs ) is problematic but common . Clear and detailed reporting of participant flow is essential to assess the generalisability and comparability of RCTs . Despite improved reporting since the implementation of the CONSORT statement , important problems remain . This paper aims : ( i ) to up date and extend previous review s evaluating reporting of participant recruitment and retention in RCTs ; ( ii ) to quantify the level of participation throughout RCTs . Methods We review ed all reports of RCTs of health care interventions and /or processes with individual r and omisation , published July – December 2004 in six major journals . Short , secondary or interim reports , and Phase I/II trials were excluded . Data recorded were : general RCT details ; inclusion of flow diagram ; participant flow throughout trial ; reasons for non-participation/withdrawal ; target sample sizes . Results 133 reports were review ed . Overall , 79 % included a flow diagram , but over a third were incomplete . The majority reported the flow of participants at each stage of the trial after r and omisation . However , 40 % failed to report the numbers assessed for eligibility . Percentages of participants retained at each stage were high : for example , 90 % of eligible individuals were r and omised , and 93 % of those r and omised were outcome assessed . On average , trials met their sample size targets . However , there were some substantial shortfalls : for example 21 % of trials reporting a sample size calculation failed to achieve adequate numbers at r and omisation , and 48 % at outcome assessment . Reporting of losses to follow up was variable and difficult to interpret . Conclusion The majority of RCTs reported the flow of participants well after r and omisation , although only two-thirds included a complete flow chart and there was great variability over the definition of " lost to follow up " . Reporting of participant eligibility was poor , making assessment s of recruitment practice and external validity difficult . Reporting of participant flow throughout RCTs could be improved by small changes to the CONSORT chart BACKGROUND Failure to recruit adequate numbers of participants represents a major barrier to the completion of r and omized controlled trials in primary care and is associated with substantial opportunity costs . However , uncertainty exists regarding the relative effectiveness of different methods to promote recruitment . OBJECTIVES The purpose of this study was to estimate the proportion of strategies used to promote patient recruitment to r and omized controlled trials in primary care that are evidence based . METHODS Investigators from seven primary care-based clinical trials of dyspepsia management aim ing to recruit a total of 6070 patients participated . Following a survey of trial organization , a Delphi technique was used to reach consensus on levels of evidence on the effectiveness of interventions or organizational characteristics in influencing recruitment . The main outcome measures were the proportions of interventions or organizational characteristics for influencing patient recruitment that are based upon r and omized controlled trials , on convincing non-experimental evidence or meeting neither of these criteria . RESULTS Out of a total of 56 interventions used across the trials , 35 ( 63 % ) were judged as evidence based . Out of a total of 29 organizational characteristics possessed by the trials , five ( 17 % ) were judged as evidence based . Across the seven dyspepsia trials , the presence of ' favourable ' organizational characteristics appeared to be important contributors towards successful recruitment . CONCLUSIONS A wide range of interventions and organizational characteristics with the potential to promote recruitment were used or possessed by seven primary care trials . Many were not evidence based . Our experience suggests that organizational characteristics could be more influential in trial recruitment than the use of specific interventions . Given the costs of primary care-based trials , research ers need more rigorous evidence to inform recruitment strategies Background Trials frequently encounter difficulties in recruitment , but evidence on effective recruitment methods in primary care is sparse . A robust test of recruitment methods involves comparing alternative methods using a r and omized trial , ' nested ' in an ongoing ' host ' trial . There are potential scientific , logistical and ethical obstacles to such studies . Methods Telephone interviews were undertaken with four groups of stakeholders ( funders , principal investigators , trial managers and ethics committee chairs ) to explore their views on the practicality and acceptability of undertaking nested trials of recruitment methods . These semi-structured interviews were transcribed and analysed thematically . Results Twenty people were interviewed . Respondents were familiar with recruitment difficulties in primary care and recognised the case for ' nested ' studies to build an evidence base on effective recruitment strategies . However , enthusiasm for this global aim was tempered by the challenges of implementation . Challenges for host studies included increasing complexity and management burden ; compatibility between the host and nested study ; and the impact of the nested study on trial design and relationships with collaborators . For nested recruitment studies , there were concerns that host study investigators might have strong preferences , limiting the nested study investigators ' control over their research , and also concerns about sample size which might limit statistical power . Nested studies needed to be compatible with the main trial and should be planned from the outset . Good communication and adequate re sources were seen as important . Conclusions Although research on recruitment was welcomed in principle , the issue of which study had control of key decisions emerged as critical . To address this concern , it appeared important to align the interests of both host and nested studies and to reduce the burden of hosting a recruitment trial . These findings should prove useful in devising a programme of research involving nested studies of recruitment interventions OBJECTIVE To compare the performance of community- vs university-based clinical centers in 3 multicenter r and omized clinical trials of intraocular surgery . METHODS Each Submacular Surgery Trials clinical center was classified as a university-based center , if the contract to perform as a center was signed by a university official , or as a community-based center . The 2 groups of centers were compared on performance , assessed cumulatively by the Submacular Surgery Trials Quality Assurance and Monitoring Subcommittee . OUTCOME MEASURES Patient accrual , completion of scheduled examinations , completion of masked vision examinations 2 years after enrollment ( the design ated primary study end point evaluation time ) , timeliness of su bmi ss 
    Output:
    
Effective interventions included the use of qualitative research to identify and overcome barriers to recruitment , reduction of the clinical workload associated with participation in RCTs and the provision of extra training and protected research time .
Meta summary analysis identified the most frequently reported subthemes to be : difficulty communicating trial methods , poor underst and ing of research and priority given to patient well-being .
The most promising intervention was the use of qualitative methods to identify and overcome barriers to  clinician recruitment activity .
The meta summary of qualitative findings identified underst and ing and communicating RCT methods as a key target for future interventions to improve recruitment .
Reinforcement of the potential benefits , both for clinicians and for their patients , could also be a successful factor in improving recruitment .