Affiliational bias in arguments regarding the use of systematic reviews in health policy decision making

Article type
Authors
Odierna D1, Gibson M2, Bero L1
1University of California, San Francisco, 333 California Street, #420, San Francisco California, United States, 94143
2Oregon Health and Science University, Center for Evidence-Based Policy, Portland, Oregon,United States
Abstract
Background: Systematic reviews inform public- and private-sector drug coverage and other health policy decisions. Arguments for and against this use of systematic reviews may be related to authors’ affiliations, income sources, and ideological backgrounds. For example, when meta-analyses concluded that exposure to second-hand smoke was harmful, the tobacco industry produced the majority of the critiques that attacked the methodology. Objectives: In order to inform policymakers about the forms of bias that may fuel the discourse surrounding the policy uses of systematic reviews, we describe the basic arguments. We identify possible biases of the presenters of the arguments and rebuttals. Methods: We perform a critical review of articles that evaluate the scope, methods, or process of systematic reviews of pharmaceuticals and other health interventions. We examine the arguments that are being made, and the distinguishing characteristics of those making the arguments. Results: Arguments that aim to instill doubts about findings unfavorable to industry, criticize methods, and question interpretation of results are most often made by industry-affiliated critics. Other arguments focus on inappropriate cost containment and the lack of applicability of systematic reviews to develop drug formularies for programs that serve diverse or ‘‘non-standard’’ populations. Arguments supporting policy uses of systematic reviews are most often made by proponents of evidence-based medicine, academic researchers, and payers. Arguments focus on systematic reviews’ standardized study designs and wide acceptance, their usefulness in developing policy that ensures access to effective medicines while limiting wasteful spending on ineffective and expensive treatments, and reviewers’ lack of financial ties to industry. Conclusion: Values play a role in health policy decisions and the evidence that informs its development. Biases and financial conflicts of interest need to be transparent and taken into account when policy makers evaluate arguments regarding the use of systematic reviews in health policy and drug coverage decisions.