To assess the evidence, you need to know it is there.

Properly conducted clinical trials provide the best evidence for whether drugs work and are safe. But about half have never been published, and trials with positive results – where the drug concerned is shown to be safe and effective – are more likely to be published than negative ones. Patients can be harmed – for example if a treatment found to be harmful in an invisible trial is then given to patients in a new one – or medicines used ineffectively or wastefully, as a result. Researchers can’t plan research properly because they don’t know what has gone before. The problems with this situation have been well documented for years, but things may now be going to change.

The AllTrials campaign is calling for all clinical trials (past and present) to be registered and all results reported. Launched in January by the British Medical Journal, Ben Goldacre’s Bad Science, Sense About Science, the James Lind Initiative and the Centre for Evidence-based Medicine, it has already attracted support from:

• NICE
• The Cochrane Collaboration
• The Wellcome Trust
• Cancer Research UK
• The British Pharmacological Society
• 80 – yes that’s 80 – patient groups including the British Heart Foundation, the MS Society and the National Childbirth Trust.

But the real feather in the cap of the campaign so far is pharma company GSK (GlaxoSmithKline), which issued a statement explaining its commitment. Tamiflu manufacturer Roche is going for the SomeTrials approach, with the promise of an “independent body” to decide which trials should be reported, in a move that has infuriated campaigners.

Read more about the campaign and sign the petition here.

An AllTrials briefing note looks at the scale of the problem and the failed attempts so far to resolve it. And a Health Technology Assessment report in 2010 concluded that, “Dissemination of research findings is likely to be a biased process..” and that the consequences of publication bias include “avoidable suffering of patients and waste of limited resources”. In December 2012, the House of Commons Science and Technology Select Committee launched an inquiry into clinical trials.

AllTrial’s success in such a short time has been phenomenal: it has harnessed the power of social media brilliantly.