Reviewer training for improving grant and journal peer review

Background Funders and scientific journals use peer review to decide which projects to fund or articles to publish. Reviewer training is an intervention to improve the quality of peer review. However, studies on the effects of such training yield inconsistent results, and there are no up‐to‐date systematic reviews addressing this question. Objectives To evaluate the effect of peer reviewer training on the quality of grant and journal peer review. Search methods We used standard, extensive Cochrane search methods. The latest search date was 27 April 2022. Selection criteria We included randomized controlled trials (RCTs; including cluster‐RCTs) that evaluated peer review with training interventions versus usual processes, no training interventions, or other interventions to improve the quality of peer review. Data collection and analysis We used standard Cochrane methods. Our primary outcomes were 1. completeness of reporting and 2. peer review detection of errors. Our secondary outcomes were 1. bibliometric scores, 2. stakeholders' assessment of peer review quality, 3. inter‐reviewer agreement, 4. process‐centred outcomes, 5. peer reviewer satisfaction, and 6. completion rate and speed of funded projects. We used the first version of the Cochrane risk of bias tool to assess the risk of bias, and we used GRADE to assess...