A man's decision to have a prostate-specific antigen (PSA) test should be an informed one. We undertook a systematic review to identify and appraise PSA decision aids and evaluations. We searched 15 electronic databases and hand-searched key journals. We also contacted key authors and organisations. All decision aids and evaluations that discussed PSA were included, with meta-analyses performed on two outcomes from the evaluations: PSA testing and patient knowledge of PSA and related issues. Seven decision aids and 11 evaluations were included. The meta-analysis showed a significantly reduced probability in PSA testing after a decision aid: -3.5% (95% confidence interval: 0.0 to 7.2%; P = 0.050). There were significant improvements in knowledge within 2 weeks after a decision aid: 19.5% (95% confidence interval: 14.2 to 24.8%; P < 0.001). The effect on knowledge was less pronounced within 12-18 months after a decision aid: 3.4% (95% confidence interval: -0.7 to 7.4%; P = 0.10). PSA decision aids improve knowledge about PSA testing, at least in the short term. Men given these decision aids seem to be less likely to have the PSA test.