The effects of shared decision-making compared to usual care for prostate cancer screening decisions: a systematic review and meta-analysis

Background Shared decision-making (SDM) is recommended for men facing prostate cancer (PC) screening decisions. We synthesize the evidence on the comparative effectiveness of SDM with usual care. Methods We searched academic and grey literature databases, and other sources for primary randomised controlled trials (RCTs) published in English comparing SDM to usual care and conducted in primary and specialised care. We assessed the individual study risk of bias, and calculated the study-specific and pooled relative risks (RR) or standardised mean differences (SMD) [with 95% confidence intervals (CI)] to perform random-effects meta-analyses for SDM-related and patient outcomes. Results Four RCTs comparing SDM to usual care, involving 1760 men, were included. SDM improved knowledge (SMD 0.23, 95%CI 0.02 to 0.43; 2 RCTs), but was not different to usual care in reducing either patient participation in prostate-specific antigen (PSA) testing (RR 1.03, 95%CI 0.90 to 1.19; 2 RCTs) or decisional conflict (SMD -0.04, 95%CI -0.23 to 0.15; SMD -0.05, 95%CI -0.24 to 0.14; 2 RCTs). Individual trial estimates (46.7%) also suggest that SDM may reduce or neutralise physicians’ tendency for PSA screening, and may improve the accuracy of patients’ perception of lifetime-risks and men’s views towards screening. There was no evidence on the effects of SDM on health outcomes. The studies represent various interventions and outcomes and are prone to risk of bias. Conclusions There is currently insufficient evidence to support a clear association of SDM on patient- and SDM-related outcomes for decisions about PSA testing. Further research needs to assess the clinical effectiveness of SDM using well-defined SDM interventions and outcomes. It should address the absence of evidence, particularly on health outcomes