Hidden conflicts of interest can distort study results and endanger trust in medical research. This is the finding of new article published in the Open Access journal Innovative Surgical Sciences, which addresses transparency and conflicts of interest in surgical studies. Transparency is particularly relevant in this area, as surgical practice is strongly influenced by medical devices, meaning there are often close relationships between industry and professionals.

A scandal from 2009 vividly demonstrates the need for research on conflicts of interest: the renowned American researcher Scott S. Reuben was sentenced to prison for falsifying years of research on postoperative pain management. Many of his studies confirmed the effectiveness of drugs manufactured by the very pharmaceutical companies that were financing his research. Yet conflicts of interest in the medical field are not just a problem in the US. In the wake of the general recommendation to receive vaccination against HPV that was issued in Germany, many asked to what extent the organization issuing the recommendation was involved with pharmaceutical companies.

In the article, "Conflicts of interest in randomised controlled surgical trials," Pascal Probst, Kathrin Grummich, Ulla Klaiber, Phillip Knebel, Alexis Ulrich, Markus W. Büchler, and Markus K. Diener evaluate the findings of a systematic overview of randomized controlled surgical studies that was compiled by the German Society of Surgery (SDGC). A total of 444 randomized controlled surgical studies from the last three decades (1985-2015) were assessed. The study comes to ambivalent conclusions. On the one hand, awareness for conflicts of interest in medical research has grown since 1984, when the New England Journal of Medicine called for open disclosure of potential conflicts. Prior to 2000, none of the examined studies made reference to possible conflicts of interest. In 2014, by contrast, 74% of studies contained such information. In total, 93 of the 444 studies (20.9%) contained conflict of interest information. On the other hand, the article concludes there is still a clear need for improvement. For example, in contrast to expectations, studies conducted with industry participation did not contain more frequent reference to conflicts of interest. Furthermore, a qualitative analysis revealed that half of the references to conflicts did not enable readers to assess whether the study was influenced by indirect interests, such as speaking fees or lobbyist activities. In some cases, the total financing received by studies was not made transparent. An additional problem was that many journals failed to provide a detailed definition for conflicts of interest.

In Innovative Surgical Science, Markus Diener (Heidelberg) and his co-authors emphasize the importance of transparency for the reliability of evidence-based medicine. Conflicts of interest should be disclosed when studies are published, they assert, calling upon publishers, journals, and reviewers do their part in insisting on transparency from authors.

"Conflicts of interest in randomised controlled surgical trials: systematic review and qualitative and quantitative analysis" Markus K. Diener et al. Innovative Surgical Sciences, DOI: 10.1515/iss-2016-0001. Ahead of print (Apr 2016)