78% of Clinical Trial Results Not Being Reported

In a recent article from the British Medical Journal, researchers at the University of Nottingham discovered that 78% of Clinical Trial results in the United States were not being reported.

"...the FDA Amendments Act (FDAAA) of 2007 required registration of summaries of trial protocols for “applicable clinical trials” (trials that are covered by the FDAAA)."

Many trial results however are not reported, which can impact practitioners and clinical decisions cannot be based on the best evidence and may be flawed.

"...no systematic evaluation of compliance with the FDAAA has been published (to the best of our knowledge). Zarin et al recently commented that the “usefulness [of ClinicalTrials.gov] depends upon the research community to submit accurate, informative data.” While searching the ClinicalTrials.gov database, we noted that studies under the jurisdiction of the FDAAA had not yet reported basic results. We decided to look into this further.

Of the 738 trials that were classified as subject to mandatory reporting, 163 (22%) had reported results. In comparison, 76/727 (10%) trials covered by the FDAAA but not subject to mandatory reporting had reported results..."

We did a subgroup analysis to determine the proportion of trials that gave the brand name of the investigated drug on the ClinicalTrials.gov record (for which we had more confidence in our categorisation of the drug as being approved by the FDA) which reported results. Of the 738 drug trials that we had classified as being subject to mandatory reporting, 347 trials gave the brand name for each and every drug in the trial. Of these 347 trials, 96 (28%) had reported results.

Reporting of summary results on ClinicalTrials.gov is an important step forward in reducing bias in the literature. We have cross referenced the ClinicalTrials.gov and Drugs@FDA databases to produce a dataset of trials that should have reported results at the time of our search, and we found that only 22% of trials had done so. If the reporting rate does not increase, the laudable FDAAA legislation will not achieve its goal of improving the accessibility of trial results.

The influence of funding body and sponsor seems to be considerable. Industry funded trials subject to mandatory reporting were more likely to report results compared with other funders. Phase III and IV studies seem more likely to be reported than phase II studies."
http://www.bmj.com/content/344/bmj.d7373



"The FDA argues that the BMJ study was flawed by including some trials completed before the 2007 law took effect, failing to exclude some exempted trials or trials of unapproved products, and including trials whose data had not yet been checked by the NIH. ClinicalTrials.gov, the public database the study’s authors drew on, also does not make clear if a trial’s deadline has been extended. Using this database, as well as information not accessible to the public, the FDA identified only 15 instances of late reporting, which the agency intends to follow up on.

Andrew Prayle, one of the paper’s authors, argued that the different findings are based on the FDA-only data. “There remain two key questions,” Prayle told Nature. “First, can they account for all of the 78 percent of trials which had not reported? We felt that this was unlikely. And second, why is it so hard to establish if a trial falls under the regulations?"
http://the-scientist.com/2012/05/02/fda-disputes-data-under-reporting/


On the surface of the information presented by the researchers, it seems very unlikely that the FDA's estimate of only 15 trials fitting this analysis, vs. the 535 discovered by the study authors.
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