Positive-outcome bias and other limitations in the outcome of research abstracts submitted to a scientific meeting. Full publication of trials initially reported as abstracts in the Australian and New Zealand Journal of Medicine 1980-2000. Comparison of registered and published primary outcomes in randomized controlled trials. Factors associated with failure to publish large randomized trials presented at an oncology meeting. Time to publication as full reports of abstracts of randomized controlled trials in cystic fibrosis. Abstracts of randomized controlled trials presented at the society for pediatric research meeting: an example of publication bias. Bias in reporting clinical trials. Commercially funded and United States-based research is more likely to be published; good-quality studies with negative outcomes are not. Full publication of results initially presented in abstracts. A meta-analysis. Quality assessment of reports on clinical trials in the Journal of Hepatology. Undisclosed changes in outcomes in randomized controlled trials: an observational study. Effect of the statistical significance of results on the time to completion and publication of randomized efficacy trials. Factors associated with acceptance and full publication of GI endoscopic research originally published in abstract form. Empirical evidence for selective reporting of outcomes in randomized trials: comparison of protocols to published articles. Discrepancy between results and abstract conclusions in industry- vs nonindustry-funded studies comparing topical prostaglandins. Forty years of randomised trials in the New Zealand Medical Journal. Outcome reporting bias in randomized trials funded by the Canadian Institutes of Health Research. Association of funding and conclusions in randomized drug trials: a reflection of treatment effect or adverse events? Outcome reporting among drug trials registered in ClinicalTrials.gov. Association of industry sponsorship to published outcomes in gastrointestinal clinical research. Publication bias in gastroenterological research - a retrospective cohort study based on abstracts submitted to a scientific meeting. Can the accuracy of abstracts be improved by providing specific instructions? A randomized controlled trial. Prevalence study of the randomized controlled trials in the Journal of Intellectual Disability Research: 1957-1994. Publication bias and meta-analyses: a practical example. Reported outcomes in major cardiovascular clinical trials funded by for-profit and not-for-profit organizations: 2000-2005. Publication and non-publication of clinical trials: longitudinal study of applications submitted to a research ethics committee. Abstracts of trials presented at the Vth World Congress of Psychiatry (Mexico, 1971): a cohort study. Are leading medical journals following their own policies on CONSORT reporting? Clinical research projects at a German medical faculty: follow-up from ethical approval to publication and citation by others. Evidence of improving quality of reporting of randomized controlled trials in subfertility. Funding source, trial outcome and reporting quality: are they related? Results of a pilot study. A comparison of handsearching versus MEDLINE searching to identify reports of randomized controlled trials. The quality of reporting of randomized clinical trials published in Ophthalmology. Editorial policy and the reporting of randomized controlled trials: a survey of instructions for authors and assessment of trial reports in Indian medical journals (2004-05). Publication bias: evidence of delayed publication in a cohort study of clinical research projects. Improving the quality of reporting randomized controlled trials in cardiothoracic surgery: the way forward. Publication bias in presentations to the Annual Scientific Congress. How easy are randomized controlled trials in epilepsy to find on Medline? The sensitivity and precision of two Medline searches. Association of trial registration with the results and conclusions of published trials of new oncology drugs. Searching MEDLINE for randomized clinical trials involving care of the newborn. A critical assessment of the quality of reporting of randomized, controlled trials in the urology literature. Quality of reporting in randomized trials published in high-quality surgical journals. Accuracy of data in abstracts of published research articles. The quality of reports of randomised trials in 2000 and 2006: comparative study of articles indexed in PubMed. Association between industry funding and statistically significant pro-industry findings in medical and surgical randomized trials. An observational study of orthopaedic abstracts and subsequent full-text publications. The retrieval of randomized clinical trials in liver disease from the medical literature. A comparison of MEDLARS and manual methods. Reporting of randomized clinical trial descriptors and use of structured abstracts. Impact of random assignment on study outcome: an empirical examination. A cohort study of summary reports of controlled trials. The quality of randomized controlled trials in major anesthesiology journals. Quality of reporting of randomized, controlled trials in cerebral palsy. The quality of reporting of randomized controlled trials of traditional Chinese medicine: a survey of 13 randomly selected journals from mainland China. Identification of randomized controlled trials from the emergency medicine literature: comparison of hand searching versus MEDLINE searching. Factors influencing publication of research results. Follow-up of applications submitted to two institutional review boards. Randomized controlled trials in pediatric surgery: could we do better? Identification and analysis of randomised controlled trials in nursing: a preliminary study. Whatever happened to abstracts from different sections of the association for research in vision and ophthalmology?
Studies with positive results are more likely to be published in biomedical journals than are studies with negative results. However, many studies submitted for consideration at scientific meetings are never published in full; bias in this setting is poorly studied.
                To identify features associated with the fate of research abstracts submitted to a scientific meeting.
                Prospective observational cohort, with 5-year follow-up of all research submitted for consideration to the major annual 1991 US research meeting in the specialty of emergency medicine.
                All research abstracts submitted for consideration at the meeting for possible presentation.
                Characteristics associated with acceptance for presentation at the meeting and subsequent publication as a full manuscript.
                A total of 492 research abstracts were submitted from programs in emergency medicine and other specialties affiliated with 103 US medical schools. A total of 179 (36%) were accepted for presentation and 214 (43%) were published in 44 journals. Of the 179 abstracts accepted for presentation, 111 studies were published. Scientific quality of abstracts or prestige of the journal in which the study was eventually published did not predict either of these outcomes. The best predictors (by logistic regression) of meeting acceptance were a subjective "originality" factor (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.13-3.89) and positive results (OR, 1.99; 95% CI, 1.07-3.84), and, for publication, meeting acceptance (OR, 2.49; 95% CI, 1.49-4.35) and large sample size (OR, 2.26; 95% CI, 1.23-4.31). Forty-nine percent (241) of abstracts did not report on blinding, and 24% (118) did not report on randomization. Acceptance and publication were both more likely for positive outcomes (P=.03). Funnel plots showed the classic distribution of positive-outcome ("publication") bias at each of the submission, acceptance, and publication phases. Meeting acceptance predicted publication with a sensitivity of only 51%, specificity of 71%, positive predictive value of 57%, and negative predictive value of 66%.
                Positive-outcome bias was evident when studies were submitted for consideration and was amplified in the selection of abstracts for both presentation and publication, neither of which was strongly related to study design or quality. Abstract Failure to identify all relevant reports of controlled trials is a potential source of bias in systematic reviews of health-care interventions. The present study aims to identify how many reports of trials -initially published as conference abstracts in the Australian and New Zealand Journal of Medicine were subsequently published in full. We identified trial reports by handsearching conference abstracts published in the Journal from 1980 to 2000. We then searched the Cochrane Controlled Trials Register and PubMed to determine how many of these had been subsequently published in full. A total of 962 reports of controlled trials was identified from the conference proceedings of 17 medical societies. Of these, 589 (61%) reports of trials were subsequently published in full, and on average within 1-2 years. Handsearching conference abstracts identified a large number of reports of controlled trials, over one-third of which were unpublished and therefore not easily accessible. As of 2005, the International Committee of Medical Journal Editors required investigators to register their trials prior to participant enrollment as a precondition for publishing the trial's findings in member journals.
                To assess the proportion of registered trials with results recently published in journals with high impact factors; to compare the primary outcomes specified in trial registries with those reported in the published articles; and to determine whether primary outcome reporting bias favored significant outcomes.
                MEDLINE via PubMed was searched for reports of randomized controlled trials (RCTs) in 3 medical areas (cardiology, rheumatology, and gastroenterology) indexed in 2008 in the 10 general medical journals and specialty journals with the highest impact factors.
                For each included article, we obtained the trial registration information using a standardized data extraction form.
                Of the 323 included trials, 147 (45.5%) were adequately registered (ie, registered before the end of the trial, with the primary outcome clearly specified). Trial registration was lacking for 89 published reports (27.6%), 45 trials (13.9%) were registered after the completion of the study, 39 (12%) were registered with no or an unclear description of the primary outcome, and 3 (0.9%) were registered after the completion of the study and had an unclear description of the primary outcome. Among articles with trials adequately registered, 31% (46 of 147) showed some evidence of discrepancies between the outcomes registered and the outcomes published. The influence of these discrepancies could be assessed in only half of them and in these statistically significant results were favored in 82.6% (19 of 23).
                Comparison of the primary outcomes of RCTs registered with their subsequent publication indicated that selective outcome reporting is prevalent. Large clinical trials are the criterion standard for making treatment decisions, and nonpublication of the results of such trials can lead to bias in the literature and contribute to inappropriate medical decisions.
                To determine the rate of full publication of large randomized trials presented at annual meetings of the American Society of Clinical Oncology (ASCO), quantify bias against publishing nonsignificant results, and identify factors associated with time to publication.
                Survey of 510 abstracts from large (sample size, > or =200), phase 3, randomized controlled trials presented at ASCO meetings between 1989 and 1998. Trial results were classified as significant (P< or =.05 for the primary outcome measure) or nonsignificant (P>.05 or not reported), and the type of presentation and sponsorship were identified. Subsequent full publication was identified using a search of MEDLINE and EMBASE, completed November 1, 2001; the search was updated in November 2002, using the Cochrane Register of Controlled Trials. Authors were contacted if the searches did not find evidence of publication.
                Publication rate at 5 years; time from presentation to full publication.
                Of 510 randomized trials, 26% were not published in full within 5 years after presentation at the meeting. Eighty-one percent of the studies with significant results had been published by this time compared with 68% of the studies with nonsignificant results (P<.001). Studies with oral or plenary presentation were published sooner than those not presented (P =.002), and studies with pharmaceutical sponsorship were published sooner than studies with cooperative group sponsorship or studies for which sponsorship was not specified (P =.02). These factors remained significant in a multivariable model. The most frequent reason cited by authors for not publishing was lack of time, funds, or other resources.
                A substantial number of large phase 3 trials presented at an international oncology meeting remain unpublished 5 years after presentation. Bias against publishing nonsignificant results is a problem even for large randomized trials. Nonpublication breaks the contract that investigators make with trial participants, funding agencies, and ethics boards. To determine 1) what proportion of abstracts of randomized controlled trials (RCTs) presented at international conferences on cystic fibrosis (CF) are published as full reports, 2) time to publication, and 3) factors that might delay or prevent publication.
                At the end of 1995, the Cochrane CF Group's register of RCTs contained 199 abstracts describing 180 RCTs. Abstracts were identified by handsearching 44 abstract books of three international CF conferences over a 30-year period. We searched the register for subsequent full reports of these RCTs and used survival analysis to investigate time to publication. Using the log-rank test, we examined 1) whether there is a difference in time to publication between reports where the investigators concluded that the test treatment was as effective as or better than the control treatment, and reports where it was not, and 2) whether there is a difference in time to publication according to sample size.
                Thirty-two percent of the 178 abstracts analyzed were subsequently published in full. Survival analysis indicated that the proportions published before 12 months, 2 years, and 5 years were 8.1%, 29%, and 40% respectively. No difference in time to publication was identified when the abstracts were stratified according to conclusions or sample size; no significant association (P > 0.05) existed between time to publication and both sample size and conclusions together.
                Only a small proportion of abstracts of RCTs presented at international conferences on CF are followed by full publication, and usually only after several years. Therefore, many potentially valuable studies do not reach a wide audience. However, we found no consistent factors which might delay or prevent publication. Publication bias toward studies that favor new therapies has been known to occur for the past 40 years, yet its implications are not well studied in child health. The increased interest in meta-analyses has highlighted the need to identify the totality of evidence when addressing treatment questions.
                To measure the percentage of randomized controlled trials (RCTs) presented at a major pediatric scientific meeting that were subsequently published as full-length articles, to investigate factors associated with publication, and to describe the variables that change from abstract to manuscript form.
                The scientific proceedings from the Society for Pediatric Research were hand searched for RCTs (1992-1995). Subsequent publication was ascertained through a search of various electronic databases. Quality of abstracts and manuscripts was measured, and data were extracted using a structured form.
                A total of 264 (59.1%) of 447 abstracts were subsequently published. Almost 64% of RCTs that were subsequently published favored new therapy compared with 43.5% of studies that were never published (P<.001). Mean effect size for published vs unpublished RCTs was 0.74 vs 0.05 (P<.001). Median sample size was larger in published (n = 45) vs unpublished (n = 34) RCTs (P =.02). Quality was significantly lower for abstracts vs published RCTs (P<.001). For 5% of abstracts that were subsequently published, the conclusion regarding treatment efficacy changed.
                Publication bias is a serious threat to assessing the effectiveness of interventions in child health, as little more than half of RCTs presented at a major scientific meeting are subsequently published. There is a need to institute an international registry of RCTs in children so that the totality of evidence can be accessed when assessing treatment effectiveness. The primary aim of the present study was to identify possible occurrence of selective reporting of the results of clinical trials to the Finnish National Agency for Medicines. Selective reporting may lead to poorly informed action or inaction by regulatory authorities.
                In 1987, 274 clinical drug trials were notified to the Finnish National Agency for Medicines. By December 1993, final reports had been received from 68 of these trials and statements that the trial had been suspended from 24 trials. The sponsors of the non-reported trials were requested to report the outcome. The outcomes, if any, of all reported and non-reported trials were classified as positive, inconclusive or negative.
                The total number of trials with positive, inconclusive or negative outcome were 111, 33 and 44, respectively; the outcomes of 86 trials could not be assessed. Final reports were received from 42/111 (38%) trials with positive, 6/33 (18%) with inconclusive and 9/44 (20%) with negative outcomes.
                Substantial evidence of selective reporting was detected, since trials with positive outcome resulted more often in submission of final report to regulatory authority than those with inconclusive or negative outcomes. Prior studies implying associations between receipt of commercial funding and positive (significant and/or pro-industry) research outcomes have analyzed only published papers, which is an insufficiently robust approach for assessing publication bias. In this study, we tested the following hypotheses regarding orthopaedic manuscripts submitted for review: (1) nonscientific variables, including receipt of commercial funding, affect the likelihood that a peer-reviewed submission will conclude with a report of a positive study outcome, and (2) positive outcomes and other, nonscientific variables are associated with acceptance for publication.
                All manuscripts about hip or knee arthroplasty that were submitted to The Journal of Bone and Joint Surgery, American Volume, over seventeen months were evaluated to determine the study design, quality, and outcome. Analyses were carried out to identify associations between scientific factors (sample size, study quality, and level of evidence) and study outcome as well as between non-scientific factors (funding source and country of origin) and study outcome. Analyses were also performed to determine whether outcome, scientific factors, or nonscientific variables were associated with acceptance for publication.
                Two hundred and nine manuscripts were reviewed. Commercial funding was not found to be associated with a positive study outcome (p = 0.668). Studies with a positive outcome were no more likely to be published than were those with a negative outcome (p = 0.410). Studies with a negative outcome were of higher quality (p = 0.003) and included larger sample sizes (p = 0.05). Commercially funded (p = 0.027) and United States-based (p = 0.020) studies were more likely to be published, even though those studies were not associated with higher quality, larger sample sizes, or lower levels of evidence (p = 0.24 to 0.79).
                Commercially funded studies submitted for review were not more likely to conclude with a positive outcome than were nonfunded studies, and studies with a positive outcome were no more likely to be published than were studies with a negative outcome. These findings contradict those of most previous analyses of published (rather than submitted) research. Commercial funding and the country of origin predict publication following peer review beyond what would be expected on the basis of study quality. Studies with a negative outcome, although seemingly superior in quality, fared no better than studies with a positive outcome in the peer-review process; this may result in inflation of apparent treatment effects when the published literature is subjected to meta-analysis. To estimate the rate of full publication of the results of randomized clinical trials initially presented as abstracts at national ophthalmology meetings in 1988 and 1989; and to combine data from this study with data from similar studies to determine the rate at which abstracts are subsequently published in full and the association between selected study characteristics and full publication.
                Ophthalmology abstracts were identified by review of 1988 and 1989 meeting abstracts for the Association for Research in Vision and Ophthalmology and the American Academy of Ophthalmology. Similar studies were identified either from reports contained in our files or through a MEDLINE search, which combined the textword "abstract" with "or" statements to the Medical Subject Headings ABSTRACTING & INDEXING, CLINICAL TRIALS, PEER REVIEW, PERIODICALS, MEDICAL SOCIETIES, PUBLISHING, MEDLINE, INFORMATION SERVICES, and REGISTRIES.
                Ophthalmology abstracts were selected from the meeting proceedings if they reported results from a randomized controlled trial. For the summary study, similar studies were eligible for inclusion if they described followup and subsequent full publication for a cohort of abstracts describing the results of any type of research study. All studies had to have followed up abstracts for at least 24 months to be included.
                Authors of ophthalmology abstracts were contacted by letter to ascertain whether there was subsequent full publication. Other information, including characteristics of the study design possibly related to publication, was taken from the abstract. For the summary study, rates of full publication were taken directly from reported results, as were associations between study factors (ie, "significant" results and sample size) and full publication.
                Sixty-six percent (61/93) of ophthalmology abstracts were published in full. Combined results from 11 studies showed that 51% (1198/2391) of all abstracts were subsequently published in full. Full publication was weakly associated with "significant" results and sample size above the median.
                Approximately one half of all studies initially presented in abstract form are subsequently published as full-length reports. Most are published in full within 2 years of appearance as abstracts. Full publication may be associated with "significant" results and sample size. Electronic searches on databases for randomised clinical trials and controlled clinical trials do not identify as many trials as handsearches, and trial reporting may be flawed. The aims were to identify all fully reported randomised clinical trials in the Journal of Hepatology and to make a qualitative assessment of the reporting.
                The publications were identified by systematically handsearching the full text of the journal and searching MEDLINE. Central dimensions of trial quality were used to assess the reporting quality of the trials.
                Randomised clinical trials represented 8.4% of the original articles (171/2028). Ten original articles (0.5%) could not be classified. A search on MEDLINE identified 81.3% of the randomised clinical trials, i.e., 139 out of the 171 identified by the handsearch. A total of 166 randomised clinical trials could be quality assessed. Forty-seven (28.3%) of them reported adequate generation of allocation sequence; 22 (13.3%) adequate allocation concealment; 95 (57.2%) allowed intention-to-treat analysis with only a few losses to follow-up; 50 (30.1%) were double-blind; 33 (19.9%) reported sample-size calculations; 13 trials (7.8%) employed the crossover design; and the median number of subjects per intervention arm in parallel group trials was 19 subjects (interquartile range: 11-31; range: 5-519). The quality of reporting was significantly better in regular issue articles than in supplement articles.
                Many important randomised clinical trials are published in the Journal of Hepatology, but there seems to be ample room for improvement of quality of reporting. We wanted to investigate the frequency of undisclosed changes in the outcomes of randomized controlled trials (RCTs) between trial registration and publication.
                Using a retrospective, nonrandom, cross-sectional study design, we investigated RCTs published in consecutive issues of 5 major medical journals during a 6-month period and their associated trials registry entries. Articles were excluded if they did not have an available trial registry entry, did not have analyzable outcomes, or were secondary publications. The primary outcome was the proportion of publications in which the primary outcome of the trial was, without disclosure, changed between that recorded in the trial registry and that reported in the final publication. The secondary outcome was the proportion of publications in which the secondary outcome was changed without disclosure.
                We reviewed 158 reports of RCTs and included 110 in the analysis. In 34 (31%), a primary outcome had been changed, and in 77 (70%), a secondary outcome had been changed.
                There are substantial and important undisclosed changes made to the outcomes of published RCTs between trial registration and publication. This finding has important implications for the interpretation of trial results. Disclosure and discussion of changes would improve transparency in the performance and reporting of trials. Medical evidence may be biased over time if completion and publication of randomized efficacy trials are delayed when results are not statistically significant.
                To evaluate whether the time to completion and the time to publication of randomized phase 2 and phase 3 trials are affected by the statistical significance of results and to describe the natural history of such trials.
                Prospective cohort of randomized efficacy trials conducted by 2 trialist groups from 1986 to 1996.
                Multicenter trial groups in human immunodeficiency virus infection sponsored by the National Institutes of Health.
                A total of 109 efficacy trials (total enrollment, 43708 patients).
                Time from start of enrollment to completion of follow-up and time from completion of follow-up to peer-reviewed publication assessed with survival analysis.
                The median time from start of enrollment to publication was 5.5 years and was substantially longer for negative trials than for results favoring an experimental arm (6.5 vs 4.3 years, respectively; P<.001; hazard ratio for time to publication for positive vs negative trials, 3.7; 95% confidence interval [CI], 1.8-7.7). This difference was mostly attributable to differences in the time from completion to publication (median, 3.0 vs 1.7 years for negative vs positive trials; P<.001). On average, trials with significant results favoring any arm completed follow-up slightly earlier than trials with nonsignificant results (median, 2.3 vs 2.5 years; P=.045), but long-protracted trials often had low event rates and failed to reach statistical significance, while trials that were terminated early had significant results. Positive trials were submitted for publication significantly more rapidly after completion than were negative trials (median, 1.0 vs 1.6 years; P=.001) and were published more rapidly after submission (median, 0.8 vs 1.1 years; P=.04).
                Among randomized efficacy trials, there is a time lag in the publication of negative findings that occurs mostly after the completion of the trial follow-up. Many abstracts submitted to annual scientific meetings never come to full publication in peer-reviewed journals. The objective of this study was to determine factors associated with the fate of endoscopic research abstracts submitted to the annual scientific meeting of the American Society for Gastrointestinal Endoscopy (ASGE).
                All abstracts (n = 461) submitted to the annual meeting of the ASGE in May of 1994 were retrospectively reviewed. The following databases were searched for evidence of publication of abstracts in full-manuscript form: Medline, HealthSTAR, Current Contents, CINHAL, and Cancerlit. All abstracts were reviewed between May 4, 1998 and June 30, 1998. Univariate and multivariate analysis were performed to determine the association between abstract characteristics and acceptance for presentation at the meeting and for publication.
                Fifty-five percent (247/451) of submitted abstracts were accepted for presentation. In univariate analysis, pediatric studies, prospective studies, randomized studies, and studies from university-affiliated medical centers (UAMC), were more likely to be accepted for presentation (p < 0.05). In multivariate analysis, the variables: pediatric studies (p = 0.01), prospective studies (p = 0.005), randomized studies (p = 0.06), and studies from UAMC (p = 0.01) predicted acceptance of abstracts for presentation at the meeting. The overall publication rate was 25.1%. The publication rates 1, 2, 3, and 4 years after the meeting were 6.7%, 16.2%, 22.8%, and 25.1%, respectively. Multivariate Cox proportional hazards analysis showed that accepted abstracts (p = 0.0003) studies reporting positive results (p = 0.0015), and studies from outside the United States (p = 0.036) were more likely to be published in manuscript form.
                The overall publication rate of abstracts reporting endoscopic research is 25%, lower than that in any published report from other medical societies. Abstracts from the United States were less likely to be published in full-manuscript form. Although there was no positive outcome bias for acceptance of abstracts for presentation at the meeting, there was bias toward publication of statistically significant results. Further investigations are warranted to determine the variation in the publication of research results according to country of origin and to determine factors that hinder publication of GI endoscopic research in manuscript form. Selective reporting of outcomes within published studies based on the nature or direction of their results has been widely suspected, but direct evidence of such bias is currently limited to case reports.
                To study empirically the extent and nature of outcome reporting bias in a cohort of randomized trials.
                Cohort study using protocols and published reports of randomized trials approved by the Scientific-Ethical Committees for Copenhagen and Frederiksberg, Denmark, in 1994-1995. The number and characteristics of reported and unreported trial outcomes were recorded from protocols, journal articles, and a survey of trialists. An outcome was considered incompletely reported if insufficient data were presented in the published articles for meta-analysis. Odds ratios relating the completeness of outcome reporting to statistical significance were calculated for each trial and then pooled to provide an overall estimate of bias. Protocols and published articles were also compared to identify discrepancies in primary outcomes.
                Completeness of reporting of efficacy and harm outcomes and of statistically significant vs nonsignificant outcomes; consistency between primary outcomes defined in the most recent protocols and those defined in published articles.
                One hundred two trials with 122 published journal articles and 3736 outcomes were identified. Overall, 50% of efficacy and 65% of harm outcomes per trial were incompletely reported. Statistically significant outcomes had a higher odds of being fully reported compared with nonsignificant outcomes for both efficacy (pooled odds ratio, 2.4; 95% confidence interval [CI], 1.4-4.0) and harm (pooled odds ratio, 4.7; 95% CI, 1.8-12.0) data. In comparing published articles with protocols, 62% of trials had at least 1 primary outcome that was changed, introduced, or omitted. Eighty-six percent of survey responders (42/49) denied the existence of unreported outcomes despite clear evidence to the contrary.
                The reporting of trial outcomes is not only frequently incomplete but also biased and inconsistent with protocols. Published articles, as well as reviews that incorporate them, may therefore be unreliable and overestimate the benefits of an intervention. To ensure transparency, planned trials should be registered and protocols should be made publicly available prior to trial completion. To investigate the relationship between industry- vs nonindustry-funded publications comparing the efficacy of topical prostaglandin analogs by evaluating the correspondence between the statistical significance of the publication's main outcome measure and its abstract conclusions.
                Retrospective, observational cohort study.
                English publications comparing the ocular hypotensive efficacy between any or all of latanoprost, travoprost, and bimatoprost were searched from the MEDLINE database. Each article was reviewed by three independent observers and was evaluated for source of funding, study quality, statistically significant main outcome measure, correspondence between results of main outcome measure and abstract conclusion, number of intraocular pressure outcomes compared, and journal impact factor. Funding was determined by published disclosure or, in cases of no documented disclosure, the corresponding author was contacted directly to confirm industry funding. Discrepancies were resolved by consensus. The main outcome measure was correspondence between abstract conclusion and reported statistical significance of the publications' main outcome measure.
                Thirty-nine publications were included, of which 29 were industry funded and 10 were nonindustry funded. The published abstract conclusion was not consistent with the results of the main outcome measure in 18 (62%) of 29 of the industry-funded studies compared with zero (0%) of 10 of the nonindustry-funded studies (P = .0006). Twenty-six (90%) of the industry-funded studies had proindustry abstract conclusions.
                Twenty-four percent of the industry-funded publications had a statistically significant main outcome measure; however, 90% of the industry-funded studies had proindustry abstract conclusions. Both readers and reviewers should scrutinize publications carefully to ensure that data support the authors' conclusions. To identify all randomised trials published in the New Zealand Medical Journal, to document the basic characteristics of these trials and to count the number that were detectable on medline.
                All issues of the New Zealand Medical Journal between 1943 and 1995 were systematically hand-searched. All trials identified were characterised and compared against the trials identified using an optimal medline search strategy.
                The handsearch identified 152 randomised controlled trials, the first published in 1955. Half the trials recruited less than 34 participants and more than 90% were of pharmaceutical interventions. Only 18% of studies reported on the method of randomisation and 13% provided evidence that final analyses were conducted on an intention to treat basis. Fifty one percent of trials employed a placebo control group and 28% involved a crossover design. Since 1966, when Medline became available, 143 trials were published of which 89 (62%) were identified by the Medline search.
                Two of the major difficulties that face those preparing systematic reviews were illustrated by this survey. First, important information on design and analysis is often missing from reports of trials. Second, a large proportion of published randomised trials are not identifiable on Medline. Standard formats for reporting the results of trials and inclusion of trials identified by hand-searching on the Cochrane Collaboration's International Register of Randomised Controlled Trials of Health Care will facilitate the future production of reliable systematic reviews. The reporting of outcomes within published randomized trials has previously been shown to be incomplete, biased and inconsistent with study protocols. We sought to determine whether outcome reporting bias would be present in a cohort of government-funded trials subjected to rigorous peer review.
                We compared protocols for randomized trials approved for funding by the Canadian Institutes of Health Research (formerly the Medical Research Council of Canada) from 1990 to 1998 with subsequent reports of the trials identified in journal publications. Characteristics of reported and unreported outcomes were recorded from the protocols and publications. Incompletely reported outcomes were defined as those with insufficient data provided in publications for inclusion in meta-analyses. An overall odds ratio measuring the association between completeness of reporting and statistical significance was calculated stratified by trial. Finally, primary outcomes specified in trial protocols were compared with those reported in publications.
                We identified 48 trials with 68 publications and 1402 outcomes. The median number of participants per trial was 299, and 44% of the trials were published in general medical journals. A median of 31% (10th-90th percentile range 5%-67%) of outcomes measured to assess the efficacy of an intervention (efficacy outcomes) and 59% (0%-100%) of those measured to assess the harm of an intervention (harm outcomes) per trial were incompletely reported. Statistically significant efficacy outcomes had a higher odds than nonsignificant efficacy outcomes of being fully reported (odds ratio 2.7; 95% confidence interval 1.5-5.0). Primary outcomes differed between protocols and publications for 40% of the trials.
                Selective reporting of outcomes frequently occurs in publications of high-quality government-funded trials. Previous studies indicate that industry-sponsored trials tend to draw proindustry conclusions.
                To explore whether the association between funding and conclusions in randomized drug trials reflects treatment effects or adverse events.
                Observational study of 370 randomized drug trials included in meta-analyses from Cochrane reviews selected from the Cochrane Library, May 2001. From a random sample of 167 Cochrane reviews, 25 contained eligible meta-analyses (assessed a binary outcome; pooled at least 5 full-paper trials of which at least 1 reported adequate and 1 reported inadequate allocation concealment). The primary binary outcome from each meta-analysis was considered the primary outcome for all trials included in each meta-analysis. The association between funding and conclusions was analyzed by logistic regression with adjustment for treatment effect, adverse events, and additional confounding factors (methodological quality, control intervention, sample size, publication year, and place of publication).
                Conclusions in trials, classified into whether the experimental drug was recommended as the treatment of choice or not.
                The experimental drug was recommended as treatment of choice in 16% of trials funded by nonprofit organizations, 30% of trials not reporting funding, 35% of trials funded by both nonprofit and for-profit organizations, and 51% of trials funded by for-profit organizations (P<.001; chi2 test). Logistic regression analyses indicated that funding, treatment effect, and double blinding were the only significant predictors of conclusions. Adjusted analyses showed that trials funded by for-profit organizations were significantly more likely to recommend the experimental drug as treatment of choice (odds ratio, 5.3; 95% confidence interval, 2.0-14.4) compared with trials funded by nonprofit organizations. This association did not appear to reflect treatment effect or adverse events.
                Conclusions in trials funded by for-profit organizations may be more positive due to biased interpretation of trial results. Readers should carefully evaluate whether conclusions in randomized trials are supported by data. Clinical trial registries are in widespread use to promote transparency around trials and their results.
                To describe characteristics of drug trials listed in ClinicalTrials.gov and examine whether the funding source of these trials is associated with favorable published outcomes.
                An observational study of safety and efficacy trials for anticholesteremics, antidepressants, antipsychotics, proton-pump inhibitors, and vasodilators conducted between 2000 and 2006.
                ClinicalTrials.gov, a Web-based registry of clinical trials launched in 1999.
                Publications resulting from the trials for the 5 drug categories of interest were identified, and data were abstracted on the trial record and publication, including timing of registration, elements of the study design, funding source, publication date, and study outcomes. Assessments were based on the primary funding categories of industry, government agencies, and nonprofit or nonfederal organizations.
                Among 546 drug trials, 346 (63%) were primarily funded by industry, 74 (14%) by government sources, and 126 (23%) by nonprofit or nonfederal organizations. Trials funded by industry were more likely to be phase 3 or 4 trials (88.7%; P < 0.001 across groups), to use an active comparator in controlled trials (36.8%; P = 0.010 across groups), to be multicenter (89.0%; P < 0.001 across groups), and to enroll more participants (median sample size, 306 participants; P < 0.001 across groups). Overall, 362 (66.3%) trials had published results. Industry-funded trials reported positive outcomes in 85.4% of publications, compared with 50.0% for government-funded trials and 71.9% for nonprofit or nonfederal organization-funded trials (P < 0.001). Trials funded by nonprofit or nonfederal sources with industry contributions were also more likely to report positive outcomes than those without industry funding (85.0% vs. 61.2%; P = 0.013). Rates of trial publication within 24 months of study completion ranged from 32.4% among industry-funded trials to 56.2% among nonprofit or nonfederal organization-funded trials without industry contributions (P = 0.005 across groups).
                The publication status of a trial could not always be confirmed, which could result in misclassification. Additional information on study protocols and comprehensive trial results were not available to further explore underlying factors for the association between funding source and outcome reporting.
                In this sample of registered drug trials, those funded by industry were less likely to be published within 2 years of study completion and were more likely to report positive outcomes than were trials funded by other sources.
                National Library of Medicine and National Institute of Child Health and Human Development, National Institutes of Health. Recent years have seen an increase in industry sponsorship of clinical trials throughout medicine. We conducted a study to evaluate the association of industry sponsorship to published outcomes in gastrointestinal (GI) clinical research. Our aims were (1) to evaluate the trends in the source of funding for GI clinical research during the period from 1992 to 2002-2003, (2) to determine whether the source of study funding predicted the likelihood that a study would publish results that favor the drug or device being tested, and (3) to determine whether differences exist in the methodologic quality of the investigational study methods used in studies funded by private industry versus other sources.
                We selected all clinical studies evaluating a drug or device from 4 prominent GI journals (Gastroenterology, The American Journal of Gastroenterology, Hepatology, and Gastrointestinal Endoscopy). All studies were abstracted by using a standardized data abstraction form. We evaluated the trends in funding source for studies published during the years 1992, 2002, and 2003. All selected studies were scored for methodologic quality by using a previously validated scoring system. The percentage of studies that reported outcomes that favored the device or drug being tested against the standard therapy or placebo was determined for each funding source. A funnel plot was constructed to assess for the presence of negative publication bias.
                A total of 6326 studies were reviewed. For the 1992 trend data, 1860 studies were reviewed, and 135 were selected for inclusion in the study. Ninety-five studies were studies involving the investigation of drugs, and 40 studies involved the testing of a device. For the 2002-2003 data 4466 studies were reviewed, and 315 were selected for inclusion in the study. Two hundred twenty-two studies were clinical trials involving the investigation of drugs, and 93 were clinical trials involving devices. In comparing 1992 to 2002, the percentage of studies funded by industry sources more than doubled from 10% to greater than 28% of the total studies assessed. There was an associated decline in the proportion of studies with funding from non-industry sources during this period (62% to less than 48%). The percentage of studies that did not disclose a funding source fell modestly from 28% to 24%. We found that 86% of studies funded by private industry reported a result favorable to the study drug or device, and 83% of studies funded by academic sources reported a result favorable to the study drug or device (P=.572). On average, studies funded by private industry had a higher methodology score than studies funded by traditional academic sources (75 of 100 vs 65 of 100; P=.005). Analysis of the funnel plot did not reveal evidence of bias against the publication of small studies with insignificant results.
                The proportion of research funded by industry has more than doubled during the last decade and currently comprises almost half of the funding for GI clinical research. Industry-sponsored studies are, on average, of superior methodologic quality to studies funded by other sources. Industry-sponsored studies in leading GI journals were no more likely than other studies to publish results that favored the study sponsor, although an extremely high percentage of all studies in these journals reported positive results. There has been only a modest decline in studies not acknowledging a funding source. The aim of this study was to examine the determinants of publication and whether publication bias occurred in gastroenterological research.
                A random sample of abstracts submitted to DDW, the major GI meeting (1992-1995) was evaluated. The publication status was determined by database searches, complemented by a mailed survey to abstract authors. Determinants of publication were examined by Cox proportional hazards model and multiple logistic regression.
                The sample included abstracts on 326 controlled clinical trials (CCT), 336 other clinical research reports (OCR), and 174 basic science studies (BSS). 392 abstracts (47%) were published as full papers. Acceptance for presentation at the meeting was a strong predictor of subsequent publication for all research types (overall, 54% vs. 34%, OR 2.3, 95% CI 1.7 to 3.1). In the multivariate analysis, multi-center status was found to predict publication (OR 2.8, 95% CI 1.6-4.9). There was no significant association between direction of study results and subsequent publication. Studies were less likely to be published in high impact journals if the results were not statistically significant (OR 0.5, 95 CI 95% 0.3-0.6). The author survey identified lack of time or interest as the main reason for failure to publish.
                Abstracts which were selected for presentation at the DDW are more likely to be followed by full publications. The statistical significance of the study results was not found to be a predictor of publication but influences the chances for high impact publication. The most-read section of a research article is the abstract, and therefore it is especially important that the abstract be accurate.
                To test the hypothesis that providing authors with specific instructions about abstract accuracy will result in improved accuracy.
                Randomized controlled trial of an educational intervention specifying 3 types of common defects in abstracts of articles that had been reviewed and were being returned to the authors with an invitation to revise.
                Proportion of abstracts containing 1 or more of the following defects: inconsistency in data between abstract and body of manuscript (text, tables, and figures), data or other information given in abstract but not in body, and/or conclusions not justified by information in the abstract.
                Of 250 manuscripts randomized, 13 were never revised and 34 were lost to follow-up, leaving a final comparison between 89 in the intervention group and 114 in the control group. Abstracts were defective in 25 (28%) and 30 (26%) cases, respectively (P=.78). Among 55 defective abstracts, 28 (51%) had inconsistencies, 16 (29%) contained data not present in the body, 8 (15%) had both types of defects, and 3 (5%) contained unjustified conclusions.
                Defects in abstracts, particularly inconsistencies between abstract and body and the presentation of data in abstract but not in body, occur frequently. Specific instructions to authors who are revising their manuscripts are ineffective in lowering this rate. Journals should include in their editing processes specific and detailed attention to abstracts. Systematic reviews of care are increasingly potent guides to clinical practice, and it is important that all relevant randomized controlled trials (RCTs) are identified by those within the speciality of learning disability who produce such works. All RCTs in the Journal of Intellectual Disability Research and its predecessor were identified by hand-searching (1957-1994), and the frequency, origin, intervention and quality of reporting of randomization were described. Electronic searches for the trials were undertaken for the years 1974-1994, and the quality of indexing was inspected and tested. These electronic searches were then compared to a 'gold standard' search. Fifty-six RCTs were identified. None contained the world 'randomized' in the title and only nine mentioned it in the abstract. Out of the 37 RCTs published between 1974 and 1994, 36 are in PsycLIT and 37 in MEDLINE. One MEDLINE record contained the wrong abstract. The methodological phrases used in the electronic records were poor, and thus, the precision of electronic searches, using both databases, was low. This international journal contains many relevant RCTs from around the world, involving several types of interventions. Unfortunately, these trials cannot be readily accessed electronically using methodological phrases designed to find RCTs. Improved quality of indexing would facilitate identification of RCTs and their dissemination. Publication bias is widely appreciated, but considerable time and effort are needed to locate and obtain data from unpublished randomized controlled trials (RCTs), those published in non-English language journals or those reported in the gray literature; for this publication, we will call this collection of trials the "gray+literature." However, excluding such trials from systematic reviews could introduce bias and give rise to misleading conclusions.
                We aimed to explore and quantify the impact of inclusion of gray+ literature on the results of all completed individual patient data (IPD) reviews coordinated by our group (13 meta-analyses). For each IPD review, results were calculated for RCTs fully published in English language journals and RCTs fully published in English language journals and the gray+literature.
                The IPD meta-analyses based only on RCTs that were fully published in English language journals tended to give more favorable results than those that included RCTs from the gray+literature. Although in most cases the addition of gray+data gave less encouraging results, moving the estimated treatment effect toward a null result, the direction of effect was not always predictable.
                We recommend that all systematic reviews should at least attempt to identify trials reported in the gray+literature and, where possible, obtain data from them. In surveys based on data available prior to 2000, clinical trials funded by for-profit organizations appeared more likely to report positive findings than those funded by not-for-profit organizations. Whether this situation has changed over the past 5 years or whether similar effects are present among jointly funded trials is unknown.
                To determine in contemporary randomized cardiovascular trials the association between funding source and the likelihood of reporting positive findings.
                We reviewed 324 consecutive superiority trials of cardiovascular medicine published between January 1, 2000, and July 30, 2005, in JAMA, The Lancet, and the New England Journal of Medicine.
                The proportion of trials favoring newer treatments over the standard of care was evaluated by funding source.
                Of the 324 superiority trials, 21 cited no funding source. Of the 104 trials funded solely by not-for-profit organizations, 51 (49%) reported evidence significantly favoring newer treatments over the standard of care, whereas 53 (51%) did not (P = .80). By contrast, 92 (67.2%) of 137 trials funded solely by for-profit organizations favored newer treatments over standard of care (P<.001). Among 62 jointly funded trials, 35 (56.5%), an intermediate proportion, favored newer treatments. For 205 randomized trials evaluating drugs, the proportions favoring newer treatments were 39.5%, not-for-profit; 54.4%, jointly funded; and 65.5%, for-profit trials (P for trend across groups = .002). For the 39 randomized trials evaluating cardiovascular devices, the proportions favoring newer treatments were 50.0%, not-for-profit; 69.2%, jointly funded; and 82.4%, for-profit trials (P for trend across groups = .07). Regardless of funding source, trials using surrogate end points, such as quantitative angiography, intravascular ultrasound, plasma biomarkers, and functional measures were more likely to report positive findings (67%) than trials using clinical end points (54.1%; P = .02).
                Recent cardiovascular trials funded by for-profit organizations are more likely to report positive findings than trials funded by not-for-profit organizations, as are trials using surrogate rather than clinical end points. Trials jointly funded by not-for-profit and for-profit organizations appear to report positive findings at a rate approximately midway between rates observed in trials supported solely by one or the other of these entities. Not all clinical trials are published, which may distort the evidence that is available in the literature. We studied the publication rate of a cohort of clinical trials and identified factors associated with publication and nonpublication of results.
                We analysed the protocols of randomized clinical trials of drug interventions submitted to the research ethics committee of University Hospital (Inselspital) Bern, Switzerland from 1988 to 1998. We identified full articles published up to 2006 by searching the Cochrane CENTRAL database (issue 02/2006) and by contacting investigators. We analyzed factors associated with the publication of trials using descriptive statistics and logistic regression models.
                451 study protocols and 375 corresponding articles were analyzed. 233 protocols resulted in at least one publication, a publication rate of 52%. A total of 366 (81%) trials were commercially funded, 47 (10%) had non-commercial funding. 346 trials (77%) were multi-centre studies and 272 of these (79%) were international collaborations. In the adjusted logistic regression model non-commercial funding (Odds Ratio [OR] 2.42, 95% CI 1.14-5.17), multi-centre status (OR 2.09, 95% CI 1.03-4.24), international collaboration (OR 1.87, 95% CI 0.99-3.55) and a sample size above the median of 236 participants (OR 2.04, 95% CI 1.23-3.39) were associated with full publication.
                In this cohort of applications to an ethics committee in Switzerland, only about half of clinical drug trials were published. Large multi-centre trials with non-commercial funding were more likely to be published than other trials, but most trials were funded by industry. Systematic reviews should identify all relevant trials in order to minimize the potential for bias and the play of chance in their results. Other specialities have shown that conference proceedings are a rich source of trials, but many of these trials are never fully published.
                All clinical trials presented at a single conference (Vth World Congress of Psychiatry, Mexico, 1971) were identified by hand searching. Full publications of these abstracts were then sought on five databases by searching for the authors or relevant key words.
                Full publications were found for 46% of the abstracts. The odds of publication decreased for abstracts that were from a non-Anglophone country or that failed to mention randomization.
                Anyone wishing to undertake a systematic review of a mental-health care topic should search relevant conference proceedings for trials. The revised Consolidated Standards of Reporting Trials (CONSORT) statement recognizes the importance of including data so that readers are able to judge the reliability or relevance of randomized controlled trial (RCT) findings. However, it is unclear whether journals consistently report the pre-randomization information necessary to assess the general applicability of trial results. The objective of this study was to assess the extent of adherence to pre-randomization data reporting in 4 leading general medicine journals, as recommended by the revised CONSORT statement over a specific time frame. A total of 480 RCTs met the eligibility criteria for review. In 2004, 138 of 246 (56%) articles reported the full CONSORT pre-randomization information, of which 121 (88%) presented this information in diagram form. In 2006, 136 of 234 (58%) reported the full information, of which 127 (93%) presented the information in a diagram. These numbers indicate no improvement in the reporting of pre-randomization information. In conclusion, reporting of the full CONSORT data remains inconsistent. We recommend that journals continue to support the CONSORT statement and ensure that adequate information is provided upon submission before commencing the peer review process. The presentation of clear, precise data will ensure that readers are able to better interpret the applicability of findings. Only data of published study results are available to the scientific community for further use such as informing future research and synthesis of available evidence. If study results are reported selectively, reporting bias and distortion of summarised estimates of effect or harm of treatments can occur. The publication and citation of results of clinical research conducted in Germany was studied.
                The protocols of clinical research projects submitted to the research ethics committee of the University of Freiburg (Germany) in 2000 were analysed. Published full articles in several databases were searched and investigators contacted. Data on study and publication characteristics were extracted from protocols and corresponding publications.
                299 study protocols were included. The most frequent study design was randomised controlled trial (141; 47%), followed by uncontrolled studies (61; 20%), laboratory studies (30; 10%) and non-randomised studies (29; 10%). 182 (61%) were multicentre studies including 97 (53%) international collaborations. 152 of 299 (51%) had commercial (co-)funding and 46 (15%) non-commercial funding. 109 of the 225 completed protocols corresponded to at least one full publication (total 210 articles); the publication rate was 48%. 168 of 210 identified publications (80%) were cited in articles indexed in the ISI Web of Science. The median was 11 citations per publication (range 0-1151).
                Results of German clinical research projects conducted are largely underreported. Barriers to successful publication need to be identified and appropriate measures taken. Close monitoring of projects until publication and adequate support provided to investigators may help remedy the prevailing underreporting of research. The quality of randomized controlled trials (RCTs) in subfertility and their suitability for inclusion in meta-analyses have been assessed in the past and found to be insufficient. Our aim was to assess whether this quality has improved over time, particularly since the publication of the Consolidated Standards of Reporting Trials (CONSORT) statement, and to assess what proportion of trials could be included in the meta-analyses of pregnancy outcomes such as those included in Cochrane Reviews.
                A selection of subfertility trials published in 1990, 1996 and 2002 was collected from the Cochrane Menstrual Disorder and Subfertility Group (MDSG) database. Only trials published in English as full journal articles, claiming to be randomized and reporting on pregnancy outcomes, were included.
                One hundred and sixty-four trials met our inclusion criteria. Twenty-four (15%) were found not to be randomized, despite claims, and only 10 trials (6%) provided adequate details on the methods of randomization and allocation concealment. Of these, only three had sufficient details extractable to allow for an intention-to-treat analysis of the outcome 'live birth'.
                Although an improvement in some subfertility-specific issues was observed, the quality of reporting of RCTs still needs to improve to make them suitable for inclusion in meta-analyses such as those in the Cochrane Library. There has been increasing concern regarding the potential effects of the commercialization of research.
                In order to examine the relationships between funding source, trial outcome and reporting quality, recent issues of five peer-reviewed, high impact factor, general medical journals were hand-searched to identify a sample of 100 randomized controlled trials (20 trials/journal). Relevant data, including funding source (industry/not-for-profit/mixed/not reported) and statistical significance of primary outcome (favouring new treatment/favouring conventional treatment/neutral/unclear), were abstracted. Quality scores were assigned using the Jadad scale and the adequacy of allocation concealment.
                Sixty-six percent of trials received some industry funding. Trial outcome was not associated with funding source (p=.461). There was a preponderance of favourable statistical conclusions among published trials with 67% reporting results that favored a new treatment whereas 6% favoured the conventional treatment. Quality scores were not associated with funding source or trial outcome.
                It is not known whether the absence of significant associations between funding source, trial outcome and reporting quality reflects a true absence of an association or is an artefact of inadequate statistical power, reliance on voluntary disclosure of funding information, a focus on trials recently published in the top medical journals, or some combination thereof. Continued and expanded monitoring of potential conflicts is recommended, particularly in light of new guidelines for disclosure that have been endorsed by the ICMJE. This study aims to compare handsearching to a basic MEDLINE search for the identification of reports of randomized trials in specialized health care journals. Twenty-two specialized health care journals, published in the U.K., were handsearched for all reports of controlled trials (as defined by the Cochrane Collaboration). The reports of trials, which were judged to be definitely randomized, were identified from a random sample of three years per journal and form one element of this study. A MEDLINE search using the publication type terms 'randomized controlled trial' and 'controlled clinical trial' was also performed for the same journal years. The reports of trials retrieved by handsearching were then compared against those retrieved from the MEDLINE search, to identify differences in retrieval between the two techniques. Reports of randomized trials identified by the MEDLINE search but not found by handsearching were individually assessed to see if they met the Cochrane eligibility criteria for a report of a randomized trial. A total of 714 reports of randomized trials were found by using a combination of both handsearching and MEDLINE searching. Of these, 369 (52 per cent) were identified only by handsearching and 32 (4 per cent) were identified only by MEDLINE searching. Of the reports identified only by handsearching, 252 had no MEDLINE record, of which 232 (92 per cent) were meeting abstracts or published in supplements; 117 (25 per cent) of the 462 reports of randomized trials which had a MEDLINE record were missed by the electronic search because they did not have either of the publication type terms 'randomized controlled trial' or 'controlled clinical trial'. This proportion varied depending on when the reports of randomized trials were published (that is, before or after the introduction of the MEDLINE publication type terms above). The highest additional yield from handsearching compared to MEDLINE searching was for reports of randomized trials published prior to 1991 and from handsearching the non-MEDLINE indexed parts of a journal. The results of this study suggest that a combination of MEDLINE and handsearching is required to identify adequately reports of randomized trials.
                Copyright Crown copyright 2002. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd. To evaluate the quality of reporting of all the new randomized clinical trials published during 1999 in OPHTHALMOLOGY: using the CONSORT statement parameters.
                Descriptive series of published studies. STUDIES INCLUDED: Randomized clinical trials.
                Eligible studies were all randomized clinical trials published in Volume 106 (1999) of OPHTHALMOLOGY: that reported the results of prospectively conducted studies in humans comparing two or more therapeutic options with regard to their effect on one or various outcomes, in which the authors stated that a process of randomization or quasi-randomization was performed before the interventions. Each study was evaluated by two independent observers establishing the specific report in the published manuscript of 57 CONSORT statement descriptors, and consensus was obtained between evaluators.
                Overall presence of CONSORT statement descriptors in published reports.
                The mean number of positive CONSORT descriptors for the 24 eligible randomized clinical trials was 33.42 (standard error of the mean [SEM] 1.57) of 57 possible. This score was significantly different (P: < 0.001) from the score of 16.6 (standard error of the mean 0.6) reported for OPHTHALMOLOGY: in the 1991 to 1994 study by Scherer and Crawley. Of the nine descriptors measuring the quality of abstract reporting, a mean of 6.25 (SEM 0.3) was included in the 24 study abstracts evaluated, significantly different from the Scherer and Crawley score (5.2, SEM 0.2. P: < 0.001). Four and six descriptors increased and decreased, respectively, their reporting in more than 20%. Key descriptors such as hypothesis postulation, primary outcome determination, sample size calculations, and a discussion of the limitations of the study such as bias, imprecision, and internal validity are still reported in less than 42% of clinical trials.
                This study describes for the first time after the adoption of the CONSORT statement recommendations the status on the quality of reporting of recently published randomized clinical trials in OPHTHALMOLOGY: Although not a direct measure of the intrinsic quality of a study, reporting quality provides the reader with useful tools for the evaluation of its validity. The quality of reporting of randomized clinical trials shows an overall improvement when compared with the period between 1991 and 1994. However, there is still significant room for improvement, especially in descriptors essential for the validation of clinical trial results that are still widely underreported. Many international journals require authors of randomized controlled trials to adhere to standards of reporting described in the statement of the Consolidated Standards of Reporting Trials (CONSORT) and the requirements issued by the International Committee of Medical Journal Editors (ICMJE). We examined the extent to which these international standards have been adopted by Indian medical journals.
                To identify Indian medical journals that publish randomized controlled trials, we did electronic searches of the websites of the National Informatics Centre (Indian Medlars Centre), Database of Open Access Journals, National Library of Medicine, WHO's Index Medicus for the South-East Asian region and Google. We analysed their instructions to authors for endorsement of the CONSORT statement and the ICMJE requirements for reporting of randomized controlled trials. We then identified all randomized controlled trials published in these journals during 2004 and 2005 and assessed them against selected CONSORT items and ICMJE requirements, and scored them on the Jadad scale.
                Of the 65 journals selected, 38 (58.5%) mentioned the ICMJE requirements in their instructions for authors but only 20 (31%) specifically required authors to submit manuscripts in accordance with the CONSORT statement. Of 151 randomized controlled trials published during 2004-05, only 4 of 13 (30.8%) selected CONSORT items were reported in > 50% of trial reports. Items reflecting internal validity were poorly reported. Jadad scores were significantly higher for general medical journals compared with specialty journals (mean difference 0.46; 95% CI: 0.15-0.78; p = 0.005) and in trials published in 2005 over those published in 2004 (mean difference 0.48; 95% CI: 0.18-0.79; p = 0.002). Ethical issues were poorly reported in one-third of reports, and sources of funding and conflicts of interest were not declared in over three-fourths. Adequacy of reporting was not related to endorsing either the CONSORT statement or the ICMJE requirements.
                Medical journals published in India should adopt internationally recognized norms for reporting clinical trials and work with authors, reviewers and institutional review boards to improve the standards of conduct, reporting and validity of inferences of trials. To determine the extent to which publication is influenced by study outcome.
                A cohort of studies submitted to a hospital ethics committee over 10 years were examined retrospectively by reviewing the protocols and by questionnaire. The primary method of analysis was Cox's proportional hazards model.
                University hospital, Sydney, Australia.
                748 eligible studies submitted to Royal Prince Alfred Hospital Ethics Committee between 1979 and 1988.
                Time to publication.
                Response to the questionnaire was received for 520 (70%) of the eligible studies. Of the 218 studies analysed with tests of significance, those with positive results (P < 0.05) were much more likely to be published than those with negative results (P > or = 0.10) (hazard ratio 2.32 (95% confidence interval 1.47 to 3.66), P = 0.0003), with a significantly shorter time to publication (median 4.8 v 8.0 years). This finding was even stronger for the group of 130 clinical trials (hazard ratio 3.13 (1.76 to 5.58). P = 0.0001), with median times to publication of 4.7 and 8.0 years respectively. These results were not materially changed after adjusting for other significant predictors of publication. Studies with indefinite conclusions (0.05 < or = P < 0.10) tended to have an even lower publication rate and longer time to publication than studies with negative results (hazard ratio 0.39 (0.13 to 1.12), P = 0.08). For the 103 studies in which outcome was rated qualitatively, there was no clear cut evidence of publication bias, although the number of studies in this group was not large.
                This study confirms the evidence of publication bias found in other studies and identifies delay in publication as an additional important factor. The study results support the need for prospective registration of trials to avoid publication bias and also support restricting the selection of trials to those started before a common date in undertaking systematic reviews. To evaluate the quality of reporting of randomized controlled trials in cardiothoracic surgery, to identify factors associated with good reporting quality, and to assess the awareness of the Consolidated Standards for Reporting of Trials statement and ascertain the views of authors reporting randomized controlled trials on the difficulties in conducting randomized controlled trials and the possible ways to further improve the reporting quality of randomized controlled trials in cardiothoracic surgery.
                Randomized controlled trials of cardiothoracic surgery published in principal cardiothoracic and 4 general medical journals in 2003 were included. The quality of reporting of randomized controlled trials was assessed by using allocation concealment, the Jadad score, and a Consolidated Standards for Reporting of Trials checklist devised for the purpose. A questionnaire survey of authors reporting randomized controlled trials in principal cardiothoracic journals in 2003 was conducted.
                The overall reporting quality of the 64 randomized controlled trials included in the analysis was suboptimal as assessed by the 3 methods adopted. Most of the authors (63.5%) were not aware of the Consolidated Standards for Reporting of Trials statement; however, awareness was not associated with reporting quality. More than 65% of the authors responded that conducting randomized controlled trials in surgical specialties was difficult, and the main difficulties were blinding and obtaining a large-enough sample size to detect statistically significant differences. Fifty-four percent of the authors responded that endorsement of the Consolidated Standards for Reporting of Trials statement by the cardiothoracic journals may improve the reporting quality.
                The quality of reporting randomized controlled trials in cardiothoracic surgery is suboptimal. Endorsement of the Consolidated Standards for Reporting of Trials statement by the cardiothoracic journals may improve the quality of reporting. Free papers presented to the Annual Scientific Congress (ASC) of the Royal Australasian College of Surgeons (RACS) were reviewed for the years 1994, 1995 and 1996. Reports were examined for evidence of publication bias.
                Suitable free papers were identified from the proceedings of the meetings and authors were contacted to obtain information about the research reported and any publications resulting from it.
                Responses were obtained from 302 of 576 presentations considered suitable. A total of 55% of responding authors reported publication of their paper. Basic science papers were most likely to be published. There was a significant bias in favour of publication of positive results (98 of 139 positive vs 76 of 159 inconclusive or negative reports; P < 0.01). Retrospective data were as likely to be published as prospective (51% and 57%, respectively). Reports describing studies of high-level evidence were more likely to be published in journals with a high impact factor.
                The ASC is a comprehensive meeting that attracts a wide range of free papers from most sections of the RACS. There appears to be no evidence of bias in selection of papers for inclusion in the meeting but there is bias in the subsequent publication, which favours positive reports. Recognition of the need for more scientifically acceptable review strategies is increasing. Systematic reviews have rarely been performed on randomized controlled trials (RCTs) in the field of epilepsy. We have 355 published RCTs on a database, which will be used as a data source from systematic reviews. We wished to test the sensitivity and precision of two Medline search strategies, and to identify reasons why RCTs were missed. Both a basic and a comprehensive search strategy were used to search Medline from 1966 to 1993. Three journals (Epilepsia, Epilepsy Research, Acta Neurological Scandinavica) were searched by hand. The sensitivity and precision of these Medline search strategies in these three journals was calculated. We investigated articles missed by our comprehensive search to ascertain why they had been missed. Of the 308 RCTs on the database published between 1966 and 1993, 275 were found by our comprehensive Medline search, whereas 103 were found by our basic search. The overall precision of our comprehensive and basic searches was 35 and 72%, respectively. The overall sensitivity of our comprehensive and basic searches was 86 and 66%, respectively. Our comprehensive search failed to find 16 RCTs published in the three journals searched by hand. Articles were missed because they were inadequately indexed on Medline and/or did not contain adequate methodological information in their titles or abstracts. To find all relevant trials, a search strategy must be as sensitive as possible, but this sensitivity inevitably involves loss of precision. The National Library of Medicine is addressing indexing problems with Medline, but the quality of reports also must be improved to enhance retrieval. Registration of clinical trials has been introduced largely to reduce bias toward statistically significant results in the trial literature. Doubts remain about whether advance registration alone is an adequate measure to reduce selective publication, selective outcome reporting, and biased design. One of the first areas of medicine in which registration was widely adopted was oncology, although the bulk of registered oncology trials remain unpublished. The net influence of registration on the literature remains untested. This study compares the prevalence of favorable results and conclusions among published reports of registered and unregistered randomized controlled trials of new oncology drugs.
                We conducted a cross-sectional study of published original research articles reporting clinical trials evaluating the efficacy of drugs newly approved for antimalignancy indications by the United States Food and Drug Administration (FDA) from 2000 through 2005. Drugs receiving first-time approval for indications in oncology were identified using the FDA web site and Thomson Centerwatch. Relevant trial reports were identified using PubMed and the Cochrane Library. Evidence of advance trial registration was obtained by a search of clinicaltrials.gov, WHO, ISRCTN, NCI-PDQ trial databases and corporate trial registries, as well as articles themselves. Data on blinding, results for primary outcomes, and author conclusions were extracted independently by two coders. Univariate and multivariate logistic regression identified associations between favorable results and conclusions and independent variables including advance registration, study design characteristics, and industry sponsorship.
                Of 137 original research reports from 115 distinct randomized trials assessing 25 newly approved drugs for treating cancer, the 54 publications describing data from trials registered prior to publication were as likely to report statistically significant efficacy results and reach conclusions favoring the test drug (for results, OR = 1.77; 95% CI = 0.87 to 3.61) as reports of trials not registered in advance. In multivariate analysis, reports of prior registered trials were again as likely to favor the test drug (OR = 1.29; 95% CI = 0.54 to 3.08); large sample sizes and surrogate outcome measures were statistically significant predictors of favorable efficacy results at p < 0.05. Subgroup analysis of the main reports from each trial (n = 115) similarly indicated that registered trials were as likely to report results favoring the test drug as trials not registered in advance (OR = 1.11; 95% CI = 0.44 to 2.80), and also that large trials and trials with nonstringent blinding were significantly more likely to report results favoring the test drug.
                Trial registration alone, without a requirement for full reporting of research results, does not appear to reduce a bias toward results and conclusions favoring new drugs in the clinical trials literature. Our findings support the inclusion of full results reporting in trial registers, as well as protocols to allow assessment of whether results have been completely reported. Randomized clinical trials make up only a small fraction of published articles concerning care of the newborn infant and an even smaller fraction of articles about all human subjects. The busy pediatrician who wants to keep abreast of the medical literature requires strategies to detect such relevant studies promptly and reliably. Computer searching of MEDLINE is an attractive, potentially powerful but not sufficiently validated means of achieving this goal. Therefore, the sensitivity, specificity, and positive predictive value of two MEDLINE search strategies designed to detect randomized clinical trials for prevention and treatment of newborn diseases among all original articles about human subjects appearing in ten pediatric and general medical journals during 1985 were determined. The yield of both MEDLINE searches was compared to that of a manual search. Fifty-three randomized clinical trials of newborn care were identified by hand search among 233 articles concerning care of the newborn and 2,988 original articles about human subjects. The sensitivities of the MEDLINE searches were 53% and 34%, respectively, and the positive predictive values were 82% and 69%, respectively. Specificity of both computer searches was virtually 100%. Twenty-one randomized clinical trials were not identified by either MEDLINE search strategy, 17 of them for failure of the indexer to assign any methodologic terms at all or failure to assign sufficiently stringent methodologic terms. Consequently, sensitivities were higher, 77% and 68% respectively, when no methodologic terms were used during repeat searches. However, positive predictive values decreased concomitantly to 20% or less.(ABSTRACT TRUNCATED AT 250 WORDS) Randomized, controlled trials are the gold standard for evidence based assessment of therapeutic interventions. In 1996 the Consolidated Standards of Reporting Trials statement was published in an effort to standardize the reporting of clinical trials. To our knowledge we report the first systematic assessment of randomized, controlled trial quality in the urology literature by Consolidated Standards of Reporting Trials standards.
                All human subject randomized, controlled trials published in 4 leading urology journals in 1996 and 2004 were identified for formal review. A standardized evaluation form was developed based on the Consolidated Standards of Reporting Trials statement. Each article was evaluated by 2 independent reviewers and discrepancies were settled by consensus. A Consolidated Standards of Reporting Trials criteria summary score was calculated on a scale of 0 to 22.
                A total of 152 randomized, controlled trials met inclusion criteria. The mean+/-SEM Consolidated Standards of Reporting Trials summary score was 10.2+/-0.3 (median 10.3) and 12.0+/-0.3 (median 12.2) in 1996 and 2004, respectively, with a mean difference of 1.8 (95% CI 1.0, 2.6; p=0.001). Reporting of important methodological criteria, eg sample size justification and randomization implementation, improved from 1996 to 2004. Improvement notwithstanding, reporting of key methodological criteria remained consistently below 50% in 2004.
                This formal review suggests that randomized, controlled trial reporting in the urology literature has improved since the publication of the Consolidated Standards of Reporting Trials statement in 1996. Certain areas, such as reporting of trial methods, continue to meet Consolidated Standards of Reporting Trials criteria in fewer than half of publications. Ongoing graduate and postgraduate education in trial design and evidence based practice may result in further improvement in randomized, controlled trial reporting. Randomized controlled trials (RCTs) in surgery can provide valuable evidence of the efficacy of interventions if they are well-designed, appropriately executed, and adequately reported. Adequate reporting of methodology in surgical RCTs is known to be poor, and adverse-event reporting in surgical research is inconsistent. The Consolidated Standards of Reporting Trials (CONSORT) statement is a framework to help authors report their findings in a transparent manner. Extensions to the CONSORT statement have been published recently to address deficiencies in adverse-event reporting and in reporting of specific criteria related to nonpharmacologic treatments. The aim of this study was to assess the quality of reporting of trial methodology and adverse events in a sample of general surgical RCTs published in high-quality surgical journals using the criteria specified in the CONSORT statements.
                We used impact factor to identify the top three ranked surgical journals in 2004. We then obtained information on all RCTs published in these journals in the 2005 calendar year. We assessed quality of reporting using Jadad score, compared the quality of RCTs from CONSORT-endorsing journals with nonendorsers, and assessed the number of RCTs adequately reporting key generic methodologic, adverse-event-related, and specific nonpharmacologic criteria.
                Of 42 RCTs analyzed, only 40% (17 of 42) had a Jadad score > or = 3. There was no significant difference in the number of high-quality RCTs published in CONSORT-endorsing journals compared with nonendorsers (p = 0.3). The median percentage of RCTs adequately reporting generic methodologic, adverse-event-related, and specific nonpharmacologic criteria was 32.5%, 17%, and 36.5%, respectively.
                Quality of reporting of generic methodologic, adverse-event-related, and specific nonpharmacologic criteria in surgical RCTs is poor. Increased attention to quality of reporting of surgical RCTs is required if studies are to meet published criteria. The section of a research article most likely to be read is the abstract, and therefore it is particularly important that the abstract reflect the article faithfully.
                To assess abstracts accompanying research articles published in 6 medical journals with respect to whether data in the abstract could be verified in the article itself.
                Analysis of simple random samples of 44 articles and their accompanying abstracts published during 1 year(July 1, 1996-June 30, 1997) in each of 5 major general medical journals (Annals of Internal Medicine, BMJ, JAMA, Lancet, and New England Journal of Medicine) and a consecutive sample of 44 articles published during 15 months (July 1, 1996-August 15, 1997) in the CMAJ.
                Abstracts were considered deficient if they contained data that were either inconsistent with corresponding data in the article's body (including tables and figures) or not found in the body at all.
                The proportion of deficient abstracts varied widely (18%-68%) and to a statistically significant degree (P<.001) among the 6 journals studied.
                Data in the abstract that are inconsistent with or absent from the article's body are common, even in large-circulation general medical journals. To examine the reporting characteristics and methodological details of randomised trials indexed in PubMed in 2000 and 2006 and assess whether the quality of reporting has improved after publication of the Consolidated Standards of Reporting Trials (CONSORT) Statement in 2001.
                Comparison of two cross sectional investigations. Study sample All primary reports of randomised trials indexed in PubMed in December 2000 (n=519) and December 2006 (n=616), including parallel group, crossover, cluster, factorial, and split body study designs.
                The proportion of general and methodological items reported, stratified by year and study design. Risk ratios with 95% confidence intervals were calculated to represent changes in reporting between 2000 and 2006.
                The majority of trials were two arm (379/519 (73%) in 2000 v 468/616 (76%) in 2006) parallel group studies (383/519 (74%) v 477/616 (78%)) published in specialty journals (482/519 (93%) v 555/616 (90%)). In both 2000 and 2006, a median of 80 participants were recruited per trial for parallel group trials. The proportion of articles that reported drug trials decreased between 2000 and 2006 (from 393/519 (76%) to 356/616 (58%)), whereas the proportion of surgery trials increased (51/519 (10%) v 128/616 (21%)). There was an increase between 2000 and 2006 in the proportion of trial reports that included details of the primary outcome (risk ratio (RR) 1.18, 95% CI 1.04 to 1.33), sample size calculation (RR 1.66, 95% CI 1.40 to 1.95), and the methods of random sequence generation (RR 1.62, 95% CI 1.32 to 1.97) and allocation concealment (RR 1.40, 95% CI 1.11 to 1.76). There was no difference in the proportion of trials that provided specific details on who was blinded (RR 0.91, 95% CI 0.75 to 1.10).
                Reporting of several important aspects of trial methods improved between 2000 and 2006; however, the quality of reporting remains well below an acceptable level. Without complete and transparent reporting of how a trial was designed and conducted, it is difficult for readers to assess its conduct and validity. Conflicting reports exist in the medical literature regarding the association between industry funding and published research findings. In this study, we examine the association between industry funding and the statistical significance of results in recently published medical and surgical trials.
                We examined a consecutive series of 332 randomized trials published between January 1999 and June 2001 in 8 leading surgical journals and 5 medical journals. Each eligible study was independently reviewed for methodological quality using a 21-point index with 5 domains: randomization, outcomes, eligibility criteria, interventions and statistical issues. Our primary analysis included studies that explicitly identified the primary outcome and reported it as statistically significant. For studies that did not explicitly identify a primary outcome, we defined a "positive" study as one with at least 1 statistically significant outcome measure. We used multivariable regression analysis to determine whether there was an association between reported industry funding and trial results, while controlling for study quality and sample size.
                Among the 332 randomized trials, there were 158 drug trials, 87 surgical trials and 87 trials of other therapies. In 122 (37%) of the trials, authors declared industry funding. An unadjusted analysis of this sample of trials revealed that industry funding was associated with a statistically significant result in favour of the new industry product (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.3-3.5). The association remained significant after adjustment for study quality and sample size (adjusted OR 1.8, 95% CI 1.1-3.0). There was a nonsignificant difference between surgical trials (OR 8.0, 95% CI 1.1-53.2) and drug trials (OR 1.6, 95% CI 1.1-2.8), both of which were likely to have a pro-industry result (relative OR 5.0, 95% CI 0.7-37.5, p = 0.14).
                Industry-funded trials are more likely to be associated with statistically significant pro-industry findings, both in medical trials and surgical interventions. Research abstracts are frequently referenced in orthopaedic textbooks and influence orthopaedic care. However, little is known about the quality of information provided in the abstracts, the frequency of publication of complete papers after presentation of abstracts, or any discrepancies between abstracts and published papers. The objective of this study was to determine the quality of information provided in orthopaedic abstracts, rates of publication of full-text articles after presentation of abstracts, predictors of publication of full-text articles, and consistency between abstracts and full-text articles.
                We retrieved all abstracts from the 1996 scientific program of the sixty-third Annual Meeting of the American Academy of Orthopaedic Surgeons. For each abstract, we recorded the completeness of reporting and key features of the study design, conduct, analysis, and interpretation. A computerized Medline and PubMed search established whether the abstract had been followed by publication of a full-text article. Finally, we evaluated the consistency of reporting between abstracts and final publications.
                The program included 465 abstracts, 66% of which were on prognostic studies. All abstracts described the study design, and 70.7% of the designs were observational. Key methodological issues were reported in less than half of the abstracts, and information on data analysis was reported in <15%. One hundred and fifty-nine (34%) of the 465 abstracts were followed by publication of a full-text article. The mean time to publication (and standard deviation) was 17.6 +/- 12 months (range, one to fifty-six months). Inconsistencies between the abstract and the full-text article included the primary outcome measure, which differed 14% of the time, and the results, which differed 19% of the time.
                Two-thirds of the orthopaedic abstracts in this sample were not followed by publication of a full-text paper. The overall quality of reporting in abstracts proved inadequate, and inconsistencies between the final published paper and the original abstract occurred frequently. The routine use of abstracts as a guide to orthopaedic practice needs to be reconsidered. Randomized clinical trials (RCTs) provide the most reliable therapeutic information available. Unfortunately, there are no systemic listing of RCTs. We compared a MEDLARS search of 3686 biomedical journals for RCTs with a manual search of the medical literature for the period 1966-1982. For the former search we used subject headings (1) liver disease or (2) biliary tract disease and subheadings (1) drug therapy, (2) surgery, (3) radiotherapy, or (4) therapy, and check tags (1) comparative study or (2) clinical research. For the manual search, the contents of 34 arbitrarily selected, gastroenterologic, hepatologic, surgical, or general journals were perused. The MEDLARS search identified 160 RCTs and 29 others were found in the references of the 160. One hundred fifty-four RCTs were identified by both methods. The manual search identified 208 RCTs and an additional 34 were found in the references of the 208. The MEDLARS search identified only 107 of 208 RCTs found in the references of the 208. The MEDLARS search identified only 107 of 208 RCTs found manually in the 36 journals, an efficiency rate of 51%. We estimate that 330 hepatobiliary RCTs had been published during this 17-year period. Sixty percent of the RCTs found by MEDLARS used the key word "randomized," "double blind," or "controlled" in the title, compared to 36% in those found by the manual search. In order to retrieve RCTs, it is essential that editors require that RCTs be identified in their titles or key words by specific terms such as "controlled," "randomized," and "double blind," that papers be so catalogued and indexed, and that searchers be instructed in appropriate search strategies. Structured abstracts, that is, abstracts that describe a study using requisite content headings, provide more informative content. Concomitant reporting in the text of the report might improve with structured abstract use because of increased awareness by authors or editors of important study areas associated with content headings.
                To assess whether structured abstract use is associated with improved reporting of randomized clinical trials.
                Survey of trial reports published the year preceding, of, and following new use of structured abstracts, found by hand searching Archives of Ophthalmology (1992-1994) and Ophthalmology (1991-1993), as well as trial reports published concurrently without change in abstract format (American Journal of Ophthalmology, 1991-1994).
                We measured the inclusion of 56 criteria derived from Consolidated Standards of Reporting Trials (CONSORT) descriptors (JAMA 1996;276:637-639) in the text of each report and calculated the number of criteria included per report and the proportion of reports including individual criteria. Reports with structured abstracts were compared with those without, and reports published in 1993 and 1994 in the American Journal of Ophthalmology were compared with those published in 1991 and 1992.
                The mean (SEM) number of criteria included by authors was 15.8 (0.4) per report in 125 trial reports. We found no difference in the mean number of criteria included or the proportion of reports that included specific criteria by journal. Following structured abstract use, there was no difference in either the mean number of criteria per report or the proportion of reports including a majority of criteria within each CONSORT subheading. Four criteria were included more often and 2 less often following structured abstract use in individual journals.
                Using CONSORT descriptor criteria to evaluate reporting quality, we found no difference in text reporting associated with structured abstract use in the journals examined. Sixty research investigations published in the biomedical literature were analyzed to examine the effect of design attributes on outcome. All 60 studies included a controlled trial involving a pretest, a therapeutic intervention, and a posttest across at least two groups. Thirty of the trials used random assignment of participants to treatment or control conditions and 30 trials employed some nonrandom method of subject assignment. Trial results were aggregated and evaluated by comparing effect sizes for the primary statistical test of the hypothesis. Data analysis revealed that the trial results, as measured by effect size, did not vary across therapeutic trials using random assignment versus those using nonrandom allocation of subjects. The impact of design attributes in the interpretation of multiple clinical trials addressing a similar research question is examined. The argument is made that various design attributes frequently associated with methodological quality should be considered as important moderator variables and their influence on trial outcome should not be assumed a priori but rather examined empirically. Substantial numbers of clinical trials continue to be reported only in summary reports that present insufficient methodological details to permit informed judgments about the likely validity of the conclusions. Using a cohort of 176 controlled trials reported in summary form, we tested the hypotheses that they would be more likely to be followed by full reports if, on the basis of the information provided in the summary report, (1) the trial was judged to be methodologically sound, (2) the results favored the test treatment, and (3) the sample size was relatively large. The results of univariate and multivariate analyses provided support for only the third of these hypotheses. Investigators, as well as those who fund and sanction the conduct of clinical research, should make greater efforts to ensure that clinical trials are reported properly. Increased attention has been directed at the quality of randomized controlled trials (RCTs) and how they are being reported. We examined leading anesthesiology journals to identify if there were specific areas for improvement in the design and analysis of published clinical studies. All RCTs that appeared between January 2000 and December 2000 in leading anesthesiology journals (Anesthesiology,Anesthesia & Analgesia,Anaesthesia, and Canadian Journal of Anaesthesia) were retrieved by a MEDLINE search. We used a previously validated assessment tool, including 14 items associated with study quality, to determine a quality score for each article. The overall mean weighted quality score was 44% +/- 16%. Overall average scores were relatively high for appropriate controls (77% +/- 7%) and discussions of side effects (67% +/- 6%). Scores were very low for randomization blinding (5% +/- 2%), blinding observers to results (1% +/- 1%), and post-beta estimates (16% +/- 13%). Important pretreatment clinical predictors were absent in 32% of all studies. Significant improvement in the reporting and conduct of RCTs is required and should focus on randomization methodology, the blinding of investigators, and sample size estimates. Repeat assessments of the literature may improve the adoption of guidelines for the improvement of the quality of randomized controlled trials. In conducting reviews on the effectiveness of physiotherapy interventions on children with cerebral palsy, the assessment of trials can be hampered by problems in reporting. Therefore, we set out to evaluate trial reporting by using the Consolidated Standards of Reporting Trials (CONSORT) statement recommendations.
                Randomized, controlled trials published in 1990 or later were identified in literature searches for reviews on the effectiveness of physiotherapy interventions on children with cerebral palsy. Two independent reviewers evaluated the trial reporting by using a modified 33-item Consolidated Standards of Reporting Trials checklist.
                We identified 15 randomized, controlled trials. Almost half (48%) of the applicable items were reported adequately. Inadequate reporting was found in the following items: outcome measures, sample-size determination, details of the sequence generation, allocation concealment and implementation of the randomization, success of assessor blinding, recruitment and follow-up dates, intention-to-treat analysis, precision of the effect size, co-interventions, and adverse events.
                Only a small number of sufficiently reported trials were found. Because nearly all items had been described in at least 1 article, high-quality reporting seems feasible. Assessment of trials depends on appropriate reporting, and poor reporting jeopardizes judgments on the clinical implications. Authors of randomized, controlled trials are encouraged to follow the Consolidated Standards of Reporting Trials criteria. There is a clear need to improve the quality of reporting of trials in this field. The number of randomized controlled trials (RCTs) of traditional Chinese medicine (TCM) is increasing. However, there have been few systematic assessments of the quality of reporting of these trials. Objective: This study was undertaken to evaluate the quality of reporting of RCTs in TCM journals published in mainland China from 1999 to 2004.
                Thirteen TCM journals were randomly selected by stratified sampling of the approximately 100 TCM journals published in mainland China. All issues of the selected journals published from 1999 to 2004 were hand-searched according to guidelines from the Cochrane Centre. All reviewers underwent training in the evaluation of RCTs at the Chinese Centre of Evidence-based Medicine. A comprehensive quality assessment of each RCT was completed using a modified version of the Consolidated Standards of Reporting Trials (CONSORT) checklist (total of 30 items) and the Jadad scale. Disagreements were resolved by consensus.
                Seven thousand four hundred twenty-two RCTs were identified. The proportion of published RCTs relative to all types of published clinical trials increased significantly over the period studied, from 18.6% in 1999 to 35.9% in 2004 (P < 0.001). The mean (SD) Jadad score was 1.03 (0.61) overall. One RCT had a Jadad score of 5 points; 14 had a score of 4 points; and 102 had a score of 3 points. The mean (SD) Jadad score was 0.85 (0.53) in 1999 (746 RCTs) and 1.20 (0.62) in 2004 (1634 RCTs). Across all trials, 39.4% of the items on the modified CONSORT checklist were reported, which was equivalent to 11.82 (5.78) of the 30 items. Some important methodologic components of RCTs were incompletely reported, such as sample-size calculation (reported in 1.1% of RCTs), randomization sequence (7.9%), allocation concealment (0.3 %), implementation of the random-allocation sequence (0%), and analysis of intention to treat (0%).
                The findings of this study indicate that the quality of reporting of RCTs of TCM has improved, but remains poor. As part of an ongoing project to identify all the randomized controlled trials (RCTs) in the emergency medicine literature, in association with the Cochrane Collaboration, 2 discrete studies were undertaken; the first, to compare motives for active participation in hand searching of the literature by emergency medicine professionals, and the second, to compare hand searching with MEDLINE searching of a number of emergency medicine journals.
                All listed members of the British Association for Emergency Medicine (BAEM) and the Society for Academic Emergency Medicine (SAEM) received a standard letter outlining the objectives of the project, with 1 of 3 headings assigned on an alternate basis. Recruited volunteers hand searched journals prioritized from the emergency medicine literature. Each issue of each journal was hand searched for RCTs. In addition, a comprehensive MEDLINE search was conducted for each journal. The yields of RCTs from the 2 searching methods were compared for all journals and for each journal individually.
                No clear motivation for participation in this work could be ascertained because of the low response rates from BAEM and SAEM (10.1% and 1.8%, respectively). Only 18 (29.0%) of the 62 journals identified were indexed by MEDLINE. In the 14 journals indexed by MEDLINE for which hand searching was completed, a total of 710 RCTs were identified by a combination of the 2 approaches; of these, 592 (83.4%) were identified by hand searching alone and 483 (68.0%) by MEDLINE searching alone. Both methods identified 365 (51. 4%) RCTs; hand searching revealed an additional 227 (32.0%) that were not identified by MEDLINE searching, and MEDLINE searching found 118 (16.6%) that were not identified by hand searching. The difference between the proportions identified by hand searching and by MEDLINE searching (15.4%; 95% confidence interval [CI], 12.7% to 17.9%) was statistically significant (McNemar's chi2 test, 1 df, 33. 8; P <.0001). This difference was not significant for 8 of the journals.
                The response rates from mailing to members of the relevant professional organizations letters requesting participation in this work were very low and suggested that such an approach was not cost-effective. However, no formal costing exercise was undertaken. Searching results showed that, in the 14 emergency medicine journals indexed by MEDLINE for which hand searching was completed, hand searching led to identification of additional RCTs (primary articles) not found through MEDLINE searching. However, hand searching, although statistically significantly better than MEDLINE searching, failed to identify some of the RCTs found by MEDLINE searching, suggesting that hand searching is not a "gold standard" method and that the dual approach, promoted by the Cochrane Collaboration, may be the optimal approach for journals indexed by MEDLINE. --To investigate factors associated with the publication of research findings, in particular, the association between "significant" results and publication.
                --Follow-up study.
                --Studies approved in 1980 or prior to 1980 by the two institutional review boards that serve The Johns Hopkins Health Institutions--one that serves the School of Medicine and Hospital and the other that serves the School of Hygiene and Public Health.
                --A total of 737 studies were followed up.
                --Of the studies for which analyses had been reported as having been performed at the time of interview, 81% from the School of Medicine and Hospital and 66% from the School of Hygiene and Public Health had been published. Publication was not associated with sample size, presence of a comparison group, or type of study (eg, observational study vs clinical trial). External funding and multiple data collection sites were positively associated with publication. There was evidence of publication bias in that for both institutional review boards there was an association between results reported to be significant and publication (adjusted odds ratio, 2.54; 95% confidence interval, 1.63 to 3.94). Contrary to popular opinion, publication bias originates primarily with investigators, not journal editors: only six of the 124 studies not published were reported to have been rejected for publication.
                --There is a statistically significant association between significant results and publication. Randomized controlled trials (RCTs) are accepted as the gold standard for assessing the effectiveness of clinical interventions but are rarely reported in pediatric surgery. Have RCTs submitted to the British Association of Paediatric Surgeons (BAPS) Annual Congress during the last 5 years been adequately designed and large enough to produce a valid result?
                Abstracts accepted by the Annual BAPS Congress meetings between 1996 and 2000 were examined in collaboration with a senior health services researcher. The quality of the design, methodology, statistical analysis and conclusions, and the adequacy of the sample size were assessed for all identifiable clinical RCTs.
                From 760 accepted abstracts, there were only 9 RCTs (1%) of clinical interventions. In only 4 trials was the relevant primary end-point specified at the outset of the study, and none documented the method of randomization. Only one abstract mentioned blinding with respect to the intervention or outcome measure. Sample sizes were inadequate to detect even large clinical differences. To date, only one of these RCTs has been published in an English-language, peer-reviewed journal.
                Clear guidelines exist for the conduct of RCTs, yet compliance with these standards was rarely documented in abstracts of pediatric surgical RCTs presented at BAPS. Sample sizes were inadequate. RCTs in pediatric surgery are difficult to perform, but the specialty would benefit from well-designed, carefully conducted, multicentre, clinical RCTs to advance evidence-based practice.
                Copyright 2003, Elsevier Science (USA). All rights reserved. To describe preliminary work undertaken for development of a nursing contribution to the Cochrane Collaboration. To ascertain whether there are randomised controlled trials (RCTs) on nursing care which need to be identified for inclusion in systematic reviews of the effects of health care.
                Searches by Medline (1966-94) and by hand of 11 nursing research journals from inception to the end of 1994 to identify RCTs and systematic reviews; and a comparison of searches by hand and by Medline for three nursing research journals.
                Total number of RCTs identified and number of RCTs published in nursing journals; the sensitivity of Medline searches; and aspects of nursing care evaluated by RCT.
                The work is ongoing and 522 reports of RCTs and 20 systematic reviews of effectiveness have been identified so far. The sensitivity of Medline searches for RCTs in nursing journals is as low as 36% for one journal and the lack of reference to research design in the title or abstract was the main reason for the lack of sensitivity.
                There are RCTs that evaluate aspects of nursing care, and are published in nursing and non-nursing journals, and are largely undertaken by nurses. These must be reviewed in ongoing systematic reviews of the effects of health care (including those undertaken as part of the Cochrane Collaboration). Nursing journals must be hand searched to identify these studies as the lack of reference to study design in the titles and abstracts of nursing trials leads to poor indexing in electronic databases such as Medline. The authors investigated the fate of abstracts from each ARVO section (May 1985 meeting), the overall publication percentage, and the journals in which the abstract-derived articles were published.
                They performed a MEDLINE search by first author for 25 or 26 randomly selected abstracts from each section to identify those that led to full-length articles in peer-reviewed journals.
                Overall, 63% of abstracts led to full-length articles in peer-reviewed journals within our search period of 87 months. The publication rate of oral presentation abstracts (68%) was significantly higher than that of poster presentation abstracts (56%). A greater proportion of basic science-oriented abstracts (67%) led to publication than the clinically oriented abstracts (56%). The rate of publication was lowest for the Cornea section (40%) and highest for Physiology and Pharmacology (80%) and Biochemistry (76%). The abstract-derived articles were published in 67 different peer-reviewed journals, with 43% of the articles appearing in only five journals.
                The fact that the majority of abstracts led to full-length articles supports ARVO's goal of a large interdisciplinary appeal with the exchange of ideas among different investigators.
Only 63% of results from abstracts describing randomized or controlled clinical trials are published in full. 'Positive' results were more frequently published than not 'positive' results.