Efforts to promote the availability of data from clinical trials have been led predominantly by regulators or drug companies and tend to focus on regulated interventions such as for drugs, biologics and medical devices.
By contrast, trials of non-regulated interventions—such as for diets, exercise programs, physiotherapy, surgical procedures or behavioral interventions—have received much less attention. To determine the benefits and harms of an intervention, randomized trial evidence is needed. These trials should be registered and published in an accurate and unbiased manner, Michael B. Bracken, the Susan Dwight Bliss Professor of Epidemiology at the Yale School of Public Health, and colleagues said in an analysis piece published in the British Medical Journal.
Ideally clinical trial protocols and raw data should be made available to ensure transparency and for further use in individual patient data meta-analyses. These imperatives are well appreciated for trials of regulated interventions, but practices are lagging for non-regulated interventions.
Everyone is likely to experience one or more non-regulated intervention in his or her life. Yet many trials in these fields are small, underpowered, and lack quality safeguards such as appropriate randomization, blinding or choice of placebo or sham control. As a result, the findings are often spurious. Meanwhile, very large, well-conducted trials on non-regulated interventions are rare, even for common lifestyle interventions such as diet and exercise programs. Some trials of non-regulated interventions such as surgical procedures and behavioral interventions have intrinsic difficulties in their conduct, such as how to standardize the intervention.
Bracken and colleagues Rafael dal-Ré of Madrid and John Ioannidis of Stanford further argue that all trials, not just those regulated by government agencies, need to be appropriately registered. At present, 39 percent of published trials but only 12 percent of registered trials are non-regulated. Registration of non-regulated trials could be improved by more journals requiring trial registration before agreeing to publish their results (at present only 28 percent do so).
Ethics committees might also insist on all trials being registered, as currently happens only in the United Kingdom, the authors said.