Introduction/Objective: Reports of properly conducted controlled trials are the foundation of safe and effective health care. However, a substantial number of trials never contribute to this foundation because they are not submitted for publication. This has important implications for patient care. First, underreporting of trials reduces the power of systematic reviews to detect moderate but clinically important treatment effects. Second, because trials showing more promising treatment effects are more likely to be submitted, research syntheses based on published studies can give misleading conclusions. Finally, patients may be asked to participate in research studies designed to address questions that have already been answered. Because of the important consequences of unreported trials, the Editors of the BMJ, Lancet, and other international medical journals have joined in calling an unreported trial amnesty. The aim of the amnesty is to make information about unpublished controlled trials publicly available.

Methods/Results/Discussion: Investigators with unreported trials are invited to register these with the journals. Any unreported trial in which participants were prospectively assigned to one of two or more alternative forms of health care using random or quasi-random allocation will be eligible for registration. Registration information (contact details, number of randomized participants, type of participants, type of intervention) can be posted, faxed or e-mailed to the journal. Trial information will then be listed on a dedicated web site. If trial data are required, for example by those conducting systematic reviews, the reviewer will be able to seek this information from the trialist. The amnesty will be launched in early September. At the Cochrane Colloquium, the preliminary results from the amnesty will be presented.