WIKIMEDIA, BRUCEBLAUSThe US Food and Drug Administration (FDA) makes available summaries of the clinical studies behind medical device approvals. But as researchers reported in The BMJ this month (June 10), these “are not easy to access,” and they found just half of the trials ultimately get published in the literature where clinicians might have an easier time reading them.
“This is important, as the new European Clinical Trials Regulation (which aims to improve clinical trials transparency) does not apply to clinical trials on medical devices, and previous research found that the FDA approves many of these devices on the basis of a single trial,” according to a post on the All Trials website, part of an initiative to get human studies registered and reported.
To conduct the latest analysis, Rita Redberg of the University of California, San Francisco, and colleagues collected documents from the FDA about 106 cardiovascular devices that received premarket approval between 2000 and 2010. Of the corresponding studies on these products, 49 percent were published in peer-reviewed journals by 2013.
“Even when trials are published, the study population, primary endpoints, and results can differ substantially from data submitted to the FDA,” Redberg’s team wrote. For instance, one fourth of the published studies included a different number of patients enrolled than the summary provided by the FDA. This perhaps hinted at a reported bias, they wrote, “further supported by the finding that sex and age demographics also differed between summary and publication in over 10% of the studies.”
“Beyond adverse effects on patients of selective reporting in medical journals, the absence of publicly available data from clinical trials violates an important ethical principle of the Declaration of Helsinki,” Sidney Wolfe, the founder of Public Citizen’s Health Research Group, wrote in a BMJ editorial. “Many people participate in research because they trust that the published results might improve the health of the general population,” Wolfe added.