Disclosure of funding source and conflict of interest: exposure of biases affecting evidence and clinical utility of plastic surgery publications

Abstract

The objective of the study is to investigate associations between research topics, level of evidence, conflict of interest, and declared sources of funding in articles published in major plastic surgery journals. All articles published in four major plastic surgery journals from September 2008 to September 2010 (Plastic and Reconstructive Surgery, Annals of Plastic Surgery, Journal of Plastic, Reconstructive and Aesthetic Surgery, and Aesthetic Surgery) were reviewed. Published articles were assessed with regards to funding sources, level of evidence (I–V), research topics, and conflicts of interest. The association between these variables was described using contingency tables and compared using chi-square tests. The 1,706 articles were reviewed from four major plastic surgery journals. Level III studies comprised the majority of studies (634, 37%). The level of evidence least frequently observed in the plastic surgery journals was level I (25, 1.4%). Studies not reporting funding sources were significantly associated with a lower level of evidence (p = 0.002). There was no significant association between source of funding and level of evidence (p = 0.219) or between the source of funding and the type of study (p = 0.075). Finally, the source of funding is significantly associated with the presence of a conflict of interest (p < 0.005). While the level of evidence was related to publication of funding, further analysis of public and private funding revealed that the level of evidence of the research conducted is independent of the source of funding. Privately funded studies are more likely to present a conflict of interest.