MORE than 25% of large randomised clinical trials registered with ClinicalTrials.gov have not published any results in medical literature or in the registry database, according to research published in the BMJ. The researchers examined 585 registered trials with at least 500 participants and which had been completed by 2009. They found 171 trials with a total of almost 300 000 participants had not been published. Industry-sponsored trials were the most likely to remain unpublished. Of unpublished trials, 78% had no results available in ClinicalTrials.gov. For trials where the recruitment status was listed as “completed”, 26% (132/513) remained unpublished, and 29 trials were described as “active, not recruiting”; with 10 of these unpublished. The BMJ authors said trial investigators and sponsors had an ethical obligation to study participants to publish trial results. “The lack of availability of results from these trials contributes to publication bias and also constitutes a failure to honor the ethical contract that is the basis for exposing study participants to the risks inherent in trial participation”, they wrote. “Additional safeguards are needed to ensure timely public dissemination of trial data.”
http://www.bmj.com/content/347/bmj.f6104
