***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 The literature on analgesic testing in man reveals a series of informational gaps . These include a failure to document the occurrence of “ trials that failed , ” the problems associated with recruiting patients and in dealing with dropouts , the relative advantages and disadvantages of different methods of assessing relief from pain , the importance of baseline variables , and the utility of global and comparative judgments by patients . A trial is described in which only 100 subjects of a total of over 8,000 patients theoretically available for study proved suitable . Significant differences between conseniers and nonconsenters and selection factors that are used in choosing an experimental population have implication s for the generalization of a study . Such conclusions have been largely ignored both in and out of the scientific literature A study was conducted to estimate the accuracy and reliability of  review ers when screening records for relevant trials for a systematic review . A sensitive search of ten electronic bibliographic data bases yielded 22 571 records of potentially relevant trials . Records were allocated to four review ers such that two review ers examined each record and so that identification of trials by each review er could be compared with those identified by each of the other review ers . Agreement between review ers was assessed using Cohen 's kappa statistic . Ascertainment intersection methods were used to estimate the likely number of trials missed by review ers . Full copies of reports were obtained and assessed independently by two research ers for eligibility for the review . Eligible reports formed the ' gold st and ard ' against which an assessment was made about the accuracy of screening by review ers . After screening , 301 of 22 571 records were identified by at least one review er as potentially relevant . Agreement was ' almost perfect ' ( kappa>0.8 ) within two pairs , ' substantial ' ( kappa>0.6 ) within three pairs and ' moderate ' ( kappa>0.4 ) within one pair . Of the 301 records selected , 273 complete reports were available . When pairs of review ers agreed on the potential relevance of records , 81 per cent were eligible ( range 69 to 91 per cent ) . If review ers disagreed , 22 per cent were eligible ( range 12 to 45 per cent ) . Single review ers missed on average 8 per cent of eligible reports ( range 0 to 24 per cent ) , whereas pairs of review ers did not miss any ( range 0 to 1 per cent ) . The use of two review ers to screen records increased the number of r and omized trials identified by an average of 9 per cent ( range 0 to 32 per cent ) . Review ers can reliably identify potentially relevant records when screening thous and s of records for eligibility . Two review ers should screen records for eligibility , whenever possible , in order to maximize ascertainment of relevant trials BACKGROUND AND OBJECTIVE To conduct a pilot study to compare the frequency of errors that accompany single vs. double data extraction , compare the estimate of treatment effect derived from these methods , and compare the time requirements for these methods . METHODS Review ers were r and omized to the role of data extractor or data verifier , and were blind to the study hypothesis . The frequency of errors associated with each method of data extraction was compared using the McNemar test . The data set for each method was used to calculate an efficacy estimate by each method , using st and ard meta-analytic techniques . The time requirement for each method was compared using a paired t-test . RESULTS Single data extraction result ed in more errors than double data extraction ( relative difference : 21.7 % , P = .019 ) . There was no substantial difference between methods in effect estimates for most outcomes . The average time spent for single data extraction  was less than the average time for double data extraction ( relative difference : 36.1 % , P = .003 ) . CONCLUSION In the case that single data extraction is used in systematic review s , review ers and readers need to be mindful of the possibility for more errors and the potential impact these errors may have on effect estimates Aims /hypothesisLifestyle modification helps in the primary prevention of diabetes in multiethnic American , Finnish and Chinese population s. In a prospect i ve community-based study , we tested whether the progression to diabetes could be influenced by interventions in native Asian Indians with IGT who were younger , leaner and more insulin resistant than the above population s. Methods We r and omised 531 ( 421 men 110 women ) subjects with IGT ( mean age 45.9±5.7 years , BMI 25.8±3.5 kg/m2 ) into four groups . Group 1 was the control , Group 2 was given advice on lifestyle modification ( LSM ) , Group 3 was treated with metformin ( MET ) and Group 4 was given LSM plus MET . The primary outcome measure was type 2 diabetes as diagnosed using World Health Organization criteria . Results The median follow-up period was 30 months , and the 3-year cumulative incidences of diabetes were 55.0 % , 39.3 % , 40.5 % and 39.5 % in Groups 1–4 , respectively . The relative risk reduction was 28.5 % with LSM ( 95 % CI 20.5–37.3 , p=0.018 ) , 26.4 % with MET ( 95 % CI 19.1–35.1 , p=0.029 ) and 28.2 % with LSM + MET ( 95 % CI 20.3–37.0 , p=0.022 ) , as compared with the control group . The number needed to treat to prevent one incident case of diabetes was 6.4 for LSM , 6.9 for MET and 6.5 for LSM + MET . Conclusions /interpretationProgression of IGT to diabetes is high in native Asian Indians .  Both LSM and MET significantly reduced the incidence of diabetes  in Asian Indians with IGT ; there was no added benefit from combining them OBJECTIVE To assess the effects of lifestyle intervention on  cardiovascular  risk factors in general and especially on fibrinolysis . DESIGN R and omized clinical study . SUBJECTS A total of 186 subjects with impaired glucose tolerance and obesity . INTERVENTIONS The intervention programme included a low-fat , high-fibre diet and regular physical exercise . Half of the participants ( n = 93 ) took part in a one-month learning and training session using different behavioural modification techniques and conducted in a full-board wellness centre ( intense intervention group ) . The other half ( n = 93 ) was r and omized a one-hour counselling session with a specially trained nurse ( usual care group ) . Follow-up was carried out after 12 months . MAIN OUTCOME MEASURES Body weight , oxygen consumption , plasminogen activator inhibitor type 1 ( PAI-1 ) activity , tissue plasminogen activator ( tPA ) antigen , fibrinogen and fasting plasma insulin measured at the start of the programme and at follow-up after 1 year . RESULTS The intense intervention group had a mean weight decline by 1 year of 5.4 kg compared to 0.5 kg in the usual care group . Oxygen consumption in the intense group increased 10 % vs. a 1 % decline in the usual care group . In the intense group , PAI-1 activity decreased 31 % ( -10.1 U mL(-1 ) ) , which was significantly more than in the usual care group ( 12 % ; -3.0 U mL(-1 ) ) . The corresponding reductions in tPA antigen were 14 % ( -1.65 microg L(-1 ) ) and 6 % ( -0.69 microg L(-1 ) ) . CONCLUSIONS The present r and omized study shows that an intense lifestyle programme has sustained beneficial effects on fibrinolysis Abstract Objective : To investigate whether including a placebo arm in a clinical trial of hormone replacement therapy influenced women 's  stated willingness to participate . Design : Quasir and omised , interview based study . Setting : 10 group practice s in the Medical Research Council 's General Practice Research Framework . Participants : 436 postmenopausal women aged 45 - 64 who had not had a hysterectomy . Main outcome measures : Stated willingness to enter a trial and reasons for the decisions made . Results : Of 218 women told about the trial without a placebo arm , 85 ( 39 % ) indicated their willingness to enter compared with 65 ( 30 % ) of the 218 women told about the trial with the placebo arm ( P=0.06 ) . Part of this difference was due to explicit reluctance to take a placebo . Altruism and personal benefit were the reasons most frequently given for wanting to take part in a trial . The reasons most frequently cited for not wanting to take part were reluctance to restart periods , not wanting to take unknown or unnecessary tablets , or not wanting to interfere with present good health . Conclusion : For preventive trials the inclusion of a placebo arm may reduce patients ' willingness to participate PURPOSE Determining eligibility for a clinical trial ( CT ) typically requires a lengthy manual review of data for a single evaluation . The cost associated with eligibility screening is typically not compensated through contracts supporting CTs . METHODS We used a real-time tracking system that captures CT evaluations and provides information on evaluation outcomes and time spent on each eligibility screening by research staff . Using these data , we describe the effort and costs of eligibility screening overall and per enrolled patient for cancer CTs . The study sample included all completed eligibility assessment ( evaluation ) records for the 18-month study period . We used generalized multinomial modeling to predict evaluation outcomes and then used the result ing parameter coefficients to estimate the effort associated with each participant , adjusted for probability of being enrolled . From these data , we calculated cost associated with eligibility screening . RESULTS We found substantial variation in attributed cost by study type and phase . The cost of eligibility screening ranged by study phase from $ 129.15 to $ 336.48 per enrolled patient . The estimated annual cost of screening was more than $ 90,000 . CONCLUSION This study provides results based on prospect ively captured effort to estimate the largely nonreimbursed costs of eligibility screening and suggests that screening can be a significant financial burden to an institution . Centers performing CTs may need to acknowledge the differences in screening costs for different study types when negotiating contracts with funding organizations . Information such as that captured here could support such negotiations to reduce the gap between reimbursed and nonreimbursed costs BACKGROUND Type 2 diabetes affects approximately 8 percent of adults in the United States . Some risk factors -- elevated plasma glucose concentrations in the fasting state and after an oral glucose load , overweight , and a sedentary lifestyle -- are potentially reversible . We hypothesized that modifying these factors with a lifestyle-intervention program or the administration of metformin would prevent or delay the development of diabetes . METHODS We r and omly assigned 3234 nondiabetic persons with elevated fasting and post-load plasma glucose concentrations to placebo , metformin ( 850 mg twice daily ) , or a lifestyle-modification program  with the goals of at least a 7 percent weight loss and at least 150 minutes of physical activity per week . The mean age of the participants was 51 years , and the mean body-mass index ( the weight in kilograms divided by the square of the height in meters ) was 34.0 ; 68 percent were women , and 45 percent were members of minority groups . RESULTS The average follow-up was 2.8 years . The incidence of diabetes was 11.0 , 7.8 , and 4.8 cases per 100 person-years in the placebo , metformin , and lifestyle groups , respectively . The lifestyle intervention reduced the incidence by 58 percent ( 95 percent confidence interval , 48 to 66 percent ) and metformin by 31 percent ( 95 percent confidence interval , 17 to 43 percent ) , as compared with placebo ; the lifestyle intervention was significantly more effective than metformin . To prevent one case of diabetes during a period of three years , 6.9 persons would have to participate in the lifestyle-intervention program , and 13.9 would have to receive metformin . CONCLUSIONS Lifestyle changes and treatment with metformin both reduced the incidence of diabetes in 
    Output:
    
This study provides qualified support for the hypothesis that prevention trials recruit a smaller proportion of those screened than treatment trials .