Authorial Conflicts of Interest and Sponsorship in Systematic Reviews and Meta-Analyses on Psoriasis

Background: Because industry influence – in the form of study sponsorship and authorial conflicts of interest (COI) – can bias the results and conclusions of systematic reviews, there is a need to understand their role in systematic reviews, particularly for common conditions like psoriasis. Objectives: This study identifies conflicts of interest and industry-author relationships in systematic reviews on psoriasis treatment. Methods: Consistent with our cross-sectional design, we searched MEDLINE and Embase for systematic reviews and meta-analyses focused on psoriasis treatment. We then performed a subgroup analysis to determine further industry ties within the systemic reviews funded by industry. Results: Our study consisted of 27 systematic reviews and meta-analyses by 146 researchers. We found that 22 (81.5%) of the included systematic reviews contained at least 1 conflicted author. Six authors (of 47; 4.1%) disclosed all COI within the systematic review, 23 (of 47; 15.7%) partially disclosed COI but were also found to have undisclosed COI, and 18 (of 47; 12.3%) did not disclose any COI. Thirteen (of 22; 59.1%) contained narratives that favored the treatment group and 19 (of 22; 86.4%) reported conclusions favoring the treatment group. Importantly, 3 systematic reviews were industry-sponsored. In terms of our subgroup analysis, we found several additional industry ties within the primary studies. Conclusion: Our study calls attention to conflicts of interest, industry sponsorship, and their influence on research outcomes in systematic reviews and meta-analyses. Further, we provide examples of how specific industry ties can influence systematic reviews and recommendations for reporting.