Studies reporting the results of industry sponsored clinical trials present a more favourable picture of the effects of drugs and medical devices than those reporting on non-industry sponsored trials, according to a new Cochrane systematic review. The researchers call for a rethink of the way that industry bias is handled in medical guidelines and reviews.
The outcomes of clinical trials influence the recommendations that doctors make about drugs and other medical interventions. Therefore, it is important that trials are designed, carried out and reported on without bias towards particular products. The fact that trials are increasingly sponsored by industry makes it difficult to ensure that this is always the case. An industry sponsor can influence results and how they are reported to present their company and products in a better light, for example, by selectively reporting positive results. Previous reviews showed that industry sponsored drug trials produce more favourable results, but the researchers wanted to expand the evidence base to medical devices and find out if new requirements for clinical trial registration had made any difference.
The researchers carried out a systematic review of 48 studies on drugs and medical devices. The drugs and devices being studied were prescribed for a wide range of different diseases and conditions, from heart disease to psychiatric conditions, and were compared to placebos or other treatments. Studies sponsored by industry reported greater benefits and fewer harmful side effects compared to studies that were not sponsored by industry. Papers describing industry sponsored studies presented more favourable overall conclusions, and results and conclusions sections in these papers were less likely to agree.
“Our results suggest that industry sponsored drug and medical device studies are more often favourable to the sponsor’s products than non- industry sponsored studies,” said lead researcher Andreas Lundh of the Nordic Cochrane Centre, Rigshospitalet in Copenhagen, Denmark. “These findings resonate with current calls for better access to information about how trials are carried out, and raw data.”