Background: Strong opinions for or against the use of systematic reviews to inform policymaking have been published in the medical literature. The purpose of this paper was to examine whether funding sources and author financial conflicts of interest were associated with whether an opinion article was supportive or critical of the use of systematic reviews for policymaking. We examined the nature of the arguments within each article, the types of disclosures present, and whether these articles are being cited in the academic literature.
Methods: We searched for articles that expressed opinions about the use of systematic reviews for policymaking. We included articles that presented opinions about the use of systematic reviews for policymaking and categorized each article as supportive or critical of such use. We extracted all arguments regarding the use of systematic reviews from each article and inductively coded each as internal or external validity argument, categorized disclosed funding sources, conflicts of interest, and article types, and systematically searched for undisclosed financial ties. We counted the number of times each article has been cited in the "Web of Science." We report descriptive statistics.
Results: Articles that were critical of the use of systematic reviews (n=25) for policymaking had disclosed or undisclosed industry ties 2.3 times more often than articles that were supportive of the use (n=34). We found that editorials, comments, letters, and perspectives lacked published disclosures nearly twice as often (60% v. 33%) as other types of articles. We also found that editorials, comments, letters, and perspectives were less frequently cited in the academic literature than other article types (median number of citations=5 v. 19).
Conclusions: It is important to consider whether an article has industry ties when evaluating the strength of the argument for or against the use of systematic reviews for policymaking. We found that journal conflict of interest disclosures are often inadequate, particularly for editorials, comments, letters, and perspectives and that these articles are being cited as evidence in the academic literature. Our results further suggest the need for more consistent and complete disclosure for all article types.