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 Review published Dec. 12 by an international team of researchers including York University Professor Joel Lexchin.
“It is important that clinical trials are free from bias because they do influence the recommendations doctors 
make about drugs and other medical interventions,” says Lexchin. “The problem is that more and more trials are sponsored by industry, making it difficult to ensure this is the case.”
Joel Lexchin
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 in this study, “Industry Sponsorship and Research Outcome”, 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.
The possible influence of study sponsorship is not always taken into account in medical guidelines and assessments of the efficacy of drugs and medical devices. The researchers suggest that guidelines and reviews could improve transparency by disclosing sponsorship when results from industry-sponsored studies are reported and by regarding industry sponsorship as a factor that increases the risk of bias.
“The findings show that there is a need for better access to information on whom has sponsored a study, how it is carried out, and what raw data was used,” says Lexchin. “We need to rethink the way that industry bias is handled in medical guidelines and reviews.”