Jeppe Schroll and Lisa Bero argue in an editorial in the Cochrane Library that clinical trial information from regulators should be included in systematic reviews of treatments. In 2014, they showed that drug reports from the European Medicines Agency (EMA) and the US Food and Drug Agency (FDA) contained enough information to be used in a systematic review. In another study, they found that when that information is included in a systematic review of a treatment, it can change the results.
Researchers conducting systematic reviews need access to information from all of the clinical trials on a treatment to make a full assessment of its benefits and harms. But the results of many trials are not published in journal articles or reported on registries like ClinicalTrials.gov, which is where those researchers usually look. Pharmaceutical companies are required to submit information from all clinical trials conducted on a treatment to get it approved by the European Medicines Agency (EMA) and the US Food and Drug Agency (FDA). Those regulator’s reports should therefore include information from all trials on the treatment, say Schroll and Bero.
To encourage more researchers to use regulatory information in their reviews, Schroll and Bero suggest that the Cochrane Handbook, which explains how to do a Cochrane systematic review, be updated to include tips on how to search the regulatory databases for otherwise unpublished data.
Reference
Jeppe Schroll, Lisa Bero. Regulatory agencies hold the key to improving Cochrane Reviews of drugs[editorial]. Cochrane Database of Systematic Reviews 2015;(4): 10.1002/14651858.ED000098