Financial and Nonfinancial (Allegiance) Conflicts of Interest in Clinical Research.

Abstract

When reading a published report of original research, how often should you take the financial and conflict of interest disclosures into consideration? By now you probably know the answer to this question: always. It has been shown time and time again that research performed by investigators who have financial ties to the company that makes the product being investigated is statistically significantly more likely to report positive outcomes such as larger effect sizes and statistically significant differences between the sponsor's product and the others (1Wixted J.J. Grover N.K. Anderson Jr., F.A. Fitzgerald Jr., R.H. Clinical outcomes in orthopaedic surgery. The collaborative efforts of orthopaedic surgeons with industry.Bull Hosp Jt Dis. 1999; 58: 161-165Google Scholar). In spinal surgery research, for example, it has been shown that statistically significant associations exist between the source of funding, study outcome, and level of evidence and that the majority of published reports represented a low level of clinical evidence and described favorable outcomes (2Amiri A.R. Kanesalingam K. Cro S. Casey A.T. Does source of funding and conflict of interest influence the outcome and quality of spinal research?.Spine J. 2014; 14: 308-314Abstract Full Text Full Text PDF PubMed Scopus (73) Google Scholar). These same biases were found in research on the use of acellular dermal matrix in abdominal surgery; an investigation revealed that studies authored by groups disclosing an industry conflict were significantly associated with reporting lower rates of postoperative complications, and, consequently, more positive research results overall (3DeGeorge Jr., B.R. Holland M.C. Drake D.B. The impact of conflict of interest in abdominal wall reconstruction with acellular dermal matrix.Ann Plast Surg. 2015; 74: 242-247Crossref PubMed Scopus (32) Google Scholar). Financial ties between sponsors and authors can take many forms: consulting or personal fees, advisory positions, research laboratory space and supplies, financial interest in the company sponsoring the research, or equity interest in the study product, to name a few. Does all this mean that research performed by investigators who have financial ties to the product's manufacturer is fatally flawed? This is an important question for readers to consider, especially as no-strings-attached government funding of medical research is fast becoming an endangered species and clinical investigators are forced to approach industry ever more often for clinical research sponsorship. Before I suggest an approach to answering this question, however, consider one last thing: the potential for investigator bias to affect study results even extends to nonfinancial connections between an intervention and the investigator. In the realm of psychotherapy, for example, it has been shown that an investigator's personal confidence in the superiority of a specific treatment influences the results of using that treatment in randomized controlled trials (4Dragioti E. Dimoliatis I. Fountoulakis K.N. Evangelou E. A systematic appraisal of allegiance effect in randomized controlled trials of psychotherapy.Ann Gen Psychiatry. 2015; 14 (eCollection 2015): 25Crossref Scopus (37) Google Scholar). This effect was substantial enough that the authors recommended that an investigator's allegiance be considered a nonfinancial conflict of interest that imparts a form of optimism bias. At this point you may be developing a migraine and wondering whether to stop reading clinical research altogether. But that would be throwing out the baby with the bathwater. The answer is to simply apply the tenets of critical appraisal. Weigh the study's results in light of the rigor of its methodology, and ask yourself some questions:•How were various forms of bias controlled for? For example, were outcomes assessors blinded to treatment (especially important in observational studies)?•If the investigation received funding from a product's manufacturer, how much control did the authors have over study design, results, or publication of findings?•Do the authors explain such relationships in detail? The quality and reputation of the journal should also be taken into account. And as always, be skeptical of the results of a single study. Consider how well the findings fit with other research. Using this approach, you can weigh the results of a new study in light of any conflict of interest disclosures and decide whether or not the findings should influence your practice.