Research without results: inadequate public reporting of clinical trial results.

Abstract Objective In order to increase transparency in the medical literature, the Food and Drug Administration (FDA) Modernization Act of 1997 and the FDA Amendment Act of 2007 required registration of all “applicable trials” with required “basic results” reporting. We evaluated the rate of compliance with the FDA mandatory results reporting in www.clinicaltrials.gov . Methods All completed registered interventional studies that may be subject to FDA regulation, one year prior to required results reporting (October 2006 to September 2007, n = 1097) and during the two years after required reporting (October 2007 to September 2008 (07–08), n = 2231 and October 2008 to September 2009 (08–09), n = 2923). Results Downloading all 99,315 records from clinicaltrials.gov, we excluded all non-applicable studies. Results reporting increased from 6.8% (n = 75) prior to mandatory reporting to 19.1% (n = 427, p  Conclusion The majority of studies registered in clinicaltrials.gov are not required to report data. Of studies that may be required to report data, compliance with data reporting has improved. The clinicaltrials.gov website is not yet a comprehensive resource for study results.