In a review of nine drugs approved by the FDA in 2001 and 2002, researchers found that if the unpublished data were included in a metanalysis of a drug’s efficacy, the result was consistent with published findings in only three of 41 cases (7%.) In the one analysis that focused on adverse events, the inclusion of unpublished data showed an “increase in harm from the drug” compared to published reports. The BMJ concluded that “missing clinical trial data” is “a threat to the integrity of evidence based medicine.”
Read more
