Presentation of Benefits and Harms in US Cancer Screening and Prevention Guidelines: Systematic Review

Background: Cancer prevention and screening guidelines are ideally suited to the task of providing high-quality benefit-harm information that informs clinical practice. We systematically examined how US guidelines present benefits and harms for recommended cancer prevention and screening interventions. Methods: We included cancer screening and prevention recommendations from: 1) the United States Preventive Services Task Force, 2) the American Cancer Society, 3) the American College of Physicians, 4) the National Comprehensive Cancer Network, and 5) other US guidelines within the National Guidelines Clearinghouse. Searches took place November 20, 2013, and January 1, 2014, and updates were reviewed through July 1, 2015. Two coders used an abstraction form to code information about benefits and harms presented anywhere within a guideline document, including appendices. The primary outcome was each recommendation's benefit-harm "comparability" rating, based on how benefits and harms were presented. Recommendations presenting absolute effects for both benefits and harms received a "comparable" rating. Other recommendations received an incomplete rating or an asymmetric rating based on prespecified criteria. Results: Fifty-five recommendations for using interventions to prevent or detect breast, prostate, colon, cervical, and lung cancer were identified among 32 guidelines. Thirty point nine percent (n = 17) received a comparable rating, 14.5% (n = 8) received an incomplete rating, and 54.5% (n = 30) received an asymmetric rating. Conclusions: Sixty-nine percent of cancer prevention and screening recommendation statements either did not quantify benefits and harms or presented them in an asymmetric manner. Improved presentation of benefits and harms in guidelines would better ensure that clinicians and patients have access to the information required for making informed decisions.