A decision aid versus shared decision making for prostate cancer screening: results of a randomized, controlled trial

Shared decision making (SDM) is widely encouraged by both the American Urological Association and Choosing Wisely for prostate cancer screening. Implementation of SDM is challenging secondary to time constraints and competing patient priorities. One strategy to mitigate the difficulties in implementing SDM is to utilize a decision aid (DA). Here we evaluate whether a DA improves a patient's prostate cancer knowledge and affects prostate-specific antigen (PSA) screening rates.

Patients were randomized to usual care (UC), DA, or DA + SDM. Perception of quality of care was measured using the Consumer Assessment of Healthcare Providers and Systems (CAHPS) survey. Outcomes were stratified by long term provider relationship (LTPR, > 3 years) versus short term provider relationship (STPR, < 3 years). Knowledge of prostate cancer screening and the decision regarding screening were assessed. Groups were compared using ANOVA and logistic regression models.

A total of 329 patients were randomized. Patients in the DA + SDM arm were significantly more likely to report discussing the implication of screening (33% DA + SDM, 22% UC, 16% DA, p = 0.0292) and answered significantly more knowledge questions correctly compared to the UC arm (5.03 versus 4.46, p = 0.046). However, those in the DA arm were significantly less likely to report that they always felt encouraged to discuss all health concerns (72% DA, 78% DA + SDM, 87% UC, p = 0.0285). Interestingly, STPR patients in the DA arm were significantly more likely to undergo PSA-based prostate cancer screening (41%) than the UC arm (8%, p = 0.019). This effect was not observed in the LTPR group.

Providing patients a DA without a personal interaction resulted in a greater chance of undergoing PSA-based screening without improving knowledge about screening or understanding of the consequences of this decision. This effect was exacerbated by a shorter term provider relationship. With complex issues such as the decision to pursue PSA-based prostate cancer screening, tools cannot substitute for direct interaction with a trusted provider.