ABSTRACT: Decision aids prepare patients to make decisions about healthcare options consistent with their preferences. Helping patients choose among available options for colorectal cancer screening is important because rates are lower than screening for other cancers. This systematic review describes studies evaluating patient decision aids for colorectal cancer screening in average-risk adults and their impact on knowledge, screening intentions, and uptake.Sources included Ovid MEDLINE, Elsevier EMBASE, EBSCO CINAHL Plus, Ovid PsycINFO through July 21, 2015, pertinent reference lists, and Cochrane review of patient decisions aids. Reviewers independently selected studies that quantitatively evaluated a decision aid compared to one or more conditions or within a pre-post evaluation. Using a standardized form, reviewers independently extracted study characteristics, interventions, comparators, and outcomes. Analysis was conducted in August 2015.Twenty-three articles representing 21 trials including 11,900 subjects were eligible. Patients exposed to a decision aid showed greater knowledge than those exposed to a control condition (mean difference=18.3 of 100; 95% CI=15.5, 21.1), were more likely to be interested in screening (pooled relative risk=1.5; 95% CI=1.2, 2.0), and more likely to be screened (pooled relative risk=1.3; 95% CI=1.1, 1.4). Decision aid patients had greater knowledge than patients receiving general colorectal cancer screening information (pooled mean difference=19.3 of 100; 95% CI=14.7, 23.8); however, there were no significant differences in screening interest or behavior.Decision aids improve knowledge and interest in screening, and lead to increased screening over no information, but their impact on screening is similar to general colorectal cancer screening information.