The ClinicalTrials.gov results database--update and key issues

Disclosure of clinical trial results when product development is abandoned

Currently, sponsors are not required to report the outcomes of clinical research on drugs or devices that do not lead to an approved product. Consequently, the public cannot benefit from scientific information derived from all failed or abandoned drugs and devices. Provisions in the U.S. Food and Drug Administration Amendments Act of 2007 provide an opportunity for the Department of Health and Human Services to rectify this situation. By reporting the results of clinical trials of abandoned products in a publicly accessible database and in the peer-reviewed journal literature, sponsors would satisfy a core ethical obligation of clinical research and enhance translational science.

The database for aggregate analysis of ClinicalTrials.gov (AACT) and subsequent regrouping by clinical specialty

BACKGROUND

The ClinicalTrials.gov registry provides information regarding characteristics of past, current, and planned clinical studies to patients, clinicians, and researchers; in addition, registry data are available for bulk download. However, issues related to data structure, nomenclature, and changes in data collection over time present challenges to the aggregate analysis and interpretation of these data in general and to the analysis of trials according to clinical specialty in particular. Improving usability of these data could enhance the utility of ClinicalTrials.gov as a research resource.

METHODS/PRINCIPAL RESULTS

The purpose of our project was twofold. First, we sought to extend the usability of ClinicalTrials.gov for research purposes by developing a database for aggregate analysis of ClinicalTrials.gov (AACT) that contains data from the 96,346 clinical trials registered as of September 27, 2010. Second, we developed and validated a methodology for annotating studies by clinical specialty, using a custom taxonomy employing Medical Subject Heading (MeSH) terms applied by an NLM algorithm, as well as MeSH terms and other disease condition terms provided by study sponsors. Clinical specialists reviewed and annotated MeSH and non-MeSH disease condition terms, and an algorithm was created to classify studies into clinical specialties based on both MeSH and non-MeSH annotations. False positives and false negatives were evaluated by comparing algorithmic classification with manual classification for three specialties.

CONCLUSIONS/SIGNIFICANCE

The resulting AACT database features study design attributes parsed into discrete fields, integrated metadata, and an integrated MeSH thesaurus, and is available for download as Oracle extracts (.dmp file and text format). This publicly-accessible dataset will facilitate analysis of studies and permit detailed characterization and analysis of the U.S. clinical trials enterprise as a whole. In addition, the methodology we present for creating specialty datasets may facilitate other efforts to analyze studies by specialty groups.

Governance of clinical research

We review the principal methods and issues in the governance of clinical research: oversight of human research by federal offices, certification of clinical trial centers, management of conflict of interest in clinical research, and trial registration and reporting.

A Web-based archive of systematic review data

Systematic reviews have become increasingly critical to informing healthcare policy; however, they remain a time-consuming and labor-intensive activity. The extraction of data from constituent studies comprises a significant portion of this effort, an activity which is often needlessly duplicated, such as when attempting to update a previously conducted review or in reviews of overlapping topics.In order to address these inefficiencies, and to improve the speed and quality of healthcare policy- and decision-making, we have initiated the development of the Systematic Review Data Repository, an open collaborative Web-based repository of systematic review data. As envisioned, this resource would serve as both a central archive and data extraction tool, shared among and freely accessible to organizations producing systematic reviews worldwide. A suite of easy-to-use software tools with a Web frontend would enable researchers to seamlessly search for and incorporate previously deposited data into their own reviews, as well as contribute their own.In developing this resource, we identified a number of technical and non-technical challenges, as well as devised a number of potential solutions, including proposals for systems and software tools to assure data quality, stratify and control user access effectively and flexibly accommodate all manner of study data, as well as means by which to govern and foster adoption of this new resource.Herein we provide an account of the rationale and development of the Systematic Review Data Repository thus far, as well as outline its future trajectory.

Research without results: inadequate public reporting of clinical trial results

OBJECTIVE

In order to increase transparency in the medical literature, the Food and Drug Administration (FDA) Modernization Act of 1997 and the FDA Amendment Act of 2007 required registration of all "applicable trials" with required "basic results" reporting. We evaluated the rate of compliance with the FDA mandatory results reporting in www.clinicaltrials.gov.

METHODS

All completed registered interventional studies that may be subject to FDA regulation, one year prior to required results reporting (October 2006 to September 2007, n = 1097) and during the two years after required reporting (October 2007 to September 2008 (07-08), n = 2231 and October 2008 to September 2009 (08-09), n = 2923).

RESULTS

Downloading all 99,315 records from clinicaltrials.gov, we excluded all non-applicable studies. Results reporting increased from 6.8% (n = 75) prior to mandatory reporting to 19.1% (n = 427, p<.01) in 07-08 and 10.8% (n = 316, p<.01) in 08-09. The odds ratio for results reporting using the 06-07 time period as the reference was 3.31 (95% CI 2.54-4.32) for 07-08 and 1.74 (1.33-2.28) for 08-09. Of the 818 trials with results in clinicaltrials.gov, the rate of published articles found decreased from 60% (n = 45) in the year prior to required reporting to 33% (n = 140, p<.001) for 07-08 and 20% (n = 63, p<.001) for 08-09 time period.

CONCLUSION

The majority of studies registered in clinicaltrials.gov are not required to report data. Of studies that may be required to report data, compliance with data reporting has improved. The clinicaltrials.gov website is not yet a comprehensive resource for study results.

Using health information technology to engage communities in health, education, and research

The August 2011 Clinical and Translational Science Awards conference "Using IT to Improve Community Health: How Health Care Reform Supports Innovation" convened four "Think Tank" sessions. Thirty individuals, representing various perspectives on community engagement, attended the "Health information technology (HIT) as a resource to improve community health and education" session, which focused on using HIT to improve patient health, education, and research involvement. Participants discussed a range of topics using a semistructured format. This article describes themes and lessons that emerged from that session, with a particular focus on using HIT to engage communities to improve health and reduce health disparities in populations.

Industry influenced evidence production in collaborative research communities: a network analysis

OBJECTIVE

To measure the relative influence that industry authors have on collaborative research communities and evidence production.

STUDY DESIGN AND SETTING

Using 22 commonly prescribed drugs, 6,711 randomized controlled trials (RCTs), and 28,104 authors, 22 collaboration networks were constructed and analyzed. The directly industry-affiliated (DIA) authors were identified in the networks according to their published affiliations. Measures of influence (network centrality) and impact (citations) were determined for every author. Network-level measures of community structure and collaborative preference were used to further characterize the groups.

RESULTS

Six percent (1,741 of 28,104) of authors listed a direct affiliation with the manufacturer of a drug evaluated in the RCT. These authors received significantly more citations (P<0.05 in 19 networks) and were significantly more central in the networks (P<0.05 in 20 networks). The networks show that DIA authors tend to have greater reach in the networks and collaborate more often with non-DIA authors despite a preference toward their own group. Potential confounders include publication bias, trial sizes, and conclusions.

CONCLUSIONS

Industry-based authors are more central in their networks and are deeply embedded within highly connected drug research communities. As a consequence, they have the potential to influence information flow in the production of evidence.

Publication of NIH funded trials registered in ClinicalTrials.gov: cross sectional analysis

OBJECTIVE

To review patterns of publication of clinical trials funded by US National Institutes of Health (NIH) in peer reviewed biomedical journals indexed by Medline.

DESIGN

Cross sectional analysis.

SETTING

Clinical trials funded by NIH and registered within ClinicalTrials.gov (clinicaltrials.gov), a trial registry and results database maintained by the US National Library of Medicine, after 30 September 2005 and updated as having been completed by 31 December 2008, allowing at least 30 months for publication after completion of the trial.

MAIN OUTCOME MEASURES

Publication and time to publication in the biomedical literature, as determined through Medline searches, the last of which was performed in June 2011.

RESULTS

Among 635 clinical trials completed by 31 December 2008, 294 (46%) were published in a peer reviewed biomedical journal, indexed by Medline, within 30 months of trial completion. The median period of follow-up after trial completion was 51 months (25th-75th centiles 40-68 months), and 432 (68%) were published overall. Among published trials, the median time to publication was 23 months (14-36 months). Trials completed in either 2007 or 2008 were more likely to be published within 30 months of study completion compared with trials completed before 2007 (54% (196/366) v 36% (98/269); P<0.001).

CONCLUSIONS

Despite recent improvement in timely publication, fewer than half of trials funded by NIH are published in a peer reviewed biomedical journal indexed by Medline within 30 months of trial completion. Moreover, after a median of 51 months after trial completion, a third of trials remained unpublished.

Delayed publication of clinical trials in cystic fibrosis

BACKGROUND

When the publication of important trial data is delayed, or data are never published, this will prevent the proper practice of evidence based medicine through robust systematic reviews. Clinical trial registries allow researchers to interrogate the trial protocol and afford the opportunity to identify studies that have been completed and so determine the time lag between completion and publication.

METHODS

We searched ClinicalTrials.gov with the keywords 'cystic fibrosis'. Intervention trials which had completed 1st Jan 1998-31st Dec 2010 were selected. Time to publication in a peer-reviewed journal was calculated. Survival analyses using the log rank test were undertaken.

RESULTS

We identified 142 records. Of these, 62 had full paper publications. The median time to publication was 3.25 years. Phase of study (phase one studies more delayed, p=0.024) but not source of funding (p=0.34) was associated with time to publication.

CONCLUSIONS

Clinical trials in cystic fibrosis take a considerable amount of time to report their findings. More importantly, a large number of trials fail to report at all.

Alive and well: the research imperative

Many features of the existing biomedical research enterprise rest on questionable judgments about the value of research. Policymakers and research ethicists make assumptions about research value that aren't necessarily warranted. A more balanced view of research value could contribute to more defensible decisions about research policy and practice.

Disclosure of investigators' recruitment performance in multicenter clinical trials: a further step for research transparency

Rafael Dal-Ré and colleagues argue that the recruitment targets and performance of all site investigators in multi-centre clinical trials should be disclosed in trial registration sites before a trial starts, and when it ends.

Results availability from clinical research of female urinary incontinence

AIMS

To ascertain possible publication bias by examining the completeness and publication of studies on nonsurgical treatments for female urinary incontinence (UI).

METHODS

We analyzed information about studies from several trial registries through May 2010. We searched Medline using study registration identifiers to determine publication status, and compared percentages of completed and published studies by study and subject characteristics.

RESULTS

Among the 166 closed studies, we found 120 completed (73%), 12 terminated (7%), 3 withdrawn (2%), and 4 (2%) that provided no reasons for noncompletion. Only 17% of closed registered studies (28/166 studies) were published in peer-reviewed journals; publication that did occur was an average of 2.2 years after study completion. The proportion of studies published did not increase over time. Studies sponsored by industry were published less often than those funded by NIH (OR = 0.04; 95%CI: 0.004-0.38). Drug studies were published less often than studies of other interventions (OR = 0.22; 95%CI: 0.05-0.96). Of the 166 closed studies, 7 (4%) posted results on the ClinicalTrials.gov website. Of Phases III and IV trials, 7% and 3% posted results, respectively.

CONCLUSIONS

The absence of results from a substantial proportion of conducted studies suggests that treatment decisions for women with UI are based on selected rather than comprehensive evidence of benefits and harms. Regulatory policy for clinical research should guarantee availability of the outcomes for the public, clinicians, and policymakers.

Consumer input into research: the Australian Cancer Trials website

BACKGROUND

The Australian Cancer Trials website (ACTO) was publicly launched in 2010 to help people search for cancer clinical trials recruiting in Australia, provide information about clinical trials and assist with doctor-patient communication about trials. We describe consumer involvement in the design and development of ACTO and report our preliminary patient evaluation of the website.

METHODS

Consumers, led by Cancer Voices NSW, provided the impetus to develop the website. Consumer representative groups were consulted by the research team during the design and development of ACTO which combines a search engine, trial details, general information about trial participation and question prompt lists. Website use was analysed. A patient evaluation questionnaire was completed at one hospital, one week after exposure to the website.

RESULTS

ACTO's main features and content reflect consumer input. In February 2011, it covered 1, 042 cancer trials. Since ACTO's public launch in November 2010, until the end of February 2011, the website has had 2, 549 new visits and generated 17, 833 page views. In a sub-study of 47 patient users, 89% found the website helpful for learning about clinical trials and all respondents thought patients should have access to ACTO.

CONCLUSIONS

The development of ACTO is an example of consumers working with doctors, researchers and policy makers to improve the information available to people whose lives are affected by cancer and to help them participate in their treatment decisions, including consideration of clinical trial enrolment. Consumer input has ensured that the website is informative, targets consumer priorities and is user-friendly. ACTO serves as a model for other health conditions.

Characteristics of randomised trials on diseases in the digestive system registered in ClinicalTrials.gov: a retrospective analysis

Objectives To evaluate the adequacy of reporting of protocols for randomised trials on diseases of the digestive system registered in http://ClinicalTrials.gov and the consistency between primary outcomes, secondary outcomes and sample size specified in http://ClinicalTrials.gov and published trials. Methods Randomised phase III trials on adult patients with gastrointestinal diseases registered before January 2009 in http://ClinicalTrials.gov were eligible for inclusion. From http://ClinicalTrials.gov all data elements in the database required by the International Committee of Medical Journal Editors (ICMJE) member journals were extracted. The subsequent publications for registered trials were identified. For published trials, data concerning publication date, primary and secondary endpoint, sample size, and whether the journal adhered to ICMJE principles were extracted. Differences between primary and secondary outcomes, sample size and sample size calculations data in http://ClinicalTrials.gov and in the published paper were registered. Results 105 trials were evaluated. 66 trials (63%) were published. 30% of trials were registered incorrectly after their completion date. Several data elements of the required ICMJE data list were not filled in, with missing data in 22% and 11%, respectively, of cases concerning the primary outcome measure and sample size. In 26% of the published papers, data on sample size calculations were missing and discrepancies between sample size reporting in http://ClinicalTrials.gov and published trials existed. Conclusion The quality of registration of randomised controlled trials still needs improvement.