Cognitive errors by individual physicians are at the root of most diagnostic errors, combining with system failures to result in preventable patient harm. Despite a rich body of literature exploring cognitive biases that contribute to misdiagnosis, few interventions to address this problem have been formally tested. This review identified 141 articles containing 3 approaches to prevent cognitive errors: improving knowledge or experience (such as using simulation training), improving clinical decision-making skills (through metacognition and reflection), and providing cognitive assistance (such as clinical decision support). However, most of the proposed interventions have not been formally tested, and even fewer have evaluated interventions outside of training settings. This group of authors also recently published a review of system interventions to prevent diagnostic errors.