Many Clinical Trials Not Listed at Clinical Study Data Request Website
Only about half of trials registered at ClinicalTrials.gov are listed at the data-sharing repository website.
(HealthDay News) —- Only about half of trials registered at ClinicalTrials.gov are listed in the largest data-sharing repository, according to a research letter published in the Journal of the American Medical Association.
Isabelle Boutron, MD, PhD, from Paris Descartes University in France, and colleagues examined the proportion of randomized clinical trials (RCTs) registered at ClinicalTrials.gov that were listed on the Clinical Study Data Request (CSDR) data-sharing repository website. ClinicalTrials.gov was searched using the names of 4 sponsors; data were downloaded for all studies listed at CSDR for the same sponsors.
The researchers found that there were 966 RCTs (462,751 participants) for the 61 targeted drugs from the 4 sponsors; 53% of these trials (with 74% of participants) were listed at CSDR. The availability of each document at CSDR varied from 83% to 99%; 40% of RCTs reported that all documents were available. The proportion of registered trials listed on CSDR ranged from 33% at Roche to 66% at GlaxoSmithKline (GSK); the proportion of trials with all information available varied from 24% at Boehringer Ingelheim to 58% at GSK.
"Despite a delay of 18 months since the completion of drug trials by the company sponsor, only 53% of the RCTs from the 4 sponsors registered at ClinicalTrials.gov were listed at CSDR, with differences between sponsors," the authors wrote.