The case is now unanswerable

The case for registering all clinical trials—first advanced a decade ago1—is now unanswerable The public has the right to know what research is being funded Researchers and research funders don't want to waste resources repeating trials already under way. And those conducting systematic reviews need to be able to identify all trials begun on a subject to avoid the problem of publication bias. Otherwise, clinicians may be deceived on what the evidence shows. Next week the Lancet, the Association of the British Pharmaceutical Industry, and the BMJ Publishing Group will hold a joint conference to promote the registering of trials.

Each year a vast financial investment is made by national funding agencies, medical research charities, and drug and device manufacturers in randomised controlled trials. Unfortunately the process is chaotic and takes little account of concurrent research. Several case studies have shown how the manipulation of trial data can provide a seriously misleading picture of an intervention's effectiveness. In a systematic review of trials using ondansetron to treat postoperative nausea and vomiting …