Have you ever questioned the validity of clinical trials data? ClinicalTrials.gov is a searchable registry and database of clinical trials. It is run by the National Library of Medicine (NLM) at the National Institutes of Health and the available information is submitted by the sponsor of the clinical trial. Drugs@FDA is a searchable registry of medicines approved by the US Food and Drug Administration (FDA). Both provide clinical trial data, but is the information provided by both sites the same and can one be used to check the validity of the other?
Researchers from The Dartmouth Institute for Health Policy and Clinical Practice and the NLM analysed a sample of 100 clinical trials from ClinicalTrials.gov and compared the results available to those on Drugs@FDA. Reassuringly, there was general agreement in the published primary outcomes and results. However, only around half of the secondary outcomes identified on CliniclTrials.gov were stated on Drugs@FDA with results for just 19%, making it difficult to confirm the validity of the data. The reporting of serious adverse events and deaths for some trials were inconsistent between the two sites. Drugs@FDA only includes key information used for regulatory approval and often collates data, such as adverse events, from all relevant trials. This makes it difficult to compare with and validate the data obtained from ClinicalTrials.gov.
For further details of the study, see the full article by Schwartz et al., published in the Annals of Internal Medicine.