Decision aids to prepare patients for shared decision making: Two randomized controlled experiments on the impact of awareness of preference-sensitivity and personal motives

Objective: To participate in shared decision making (SDM), patients need to understand their options and develop trust in their own decision-making abilities. Two experiments investigated the potential of decision aids (DAs) in preparing patients for SDM by raising awareness of preference-sensitivity (Study 1) and showing possible personal motives for decision making (Study 2) in addition to providing information about the treatment options.

Methods: Participants (Study 1: N = 117; Study 2: N = 217) were put into two scenarios (Study 1: cruciate ligament rupture; Study 2: contraception), watched a consultation video and were randomized into one of three groups where they received additional information in the form of (a) narrative patient testimonials; (b) non-narrative decision strategies; and (c) an unrelated text (control group).

Results: Participants who viewed the patient testimonials or decision strategies felt better prepared for a decision (Study 1: P < .001, ${\eta }_P^2$ = 0.43; Study 2: P < .001, ${\eta }_P^2$ = 0.57) and evaluated the decision-making process more positively (Study 2: P < .001, ${\eta }_P^2$ = 0.13) than participants in the control condition. Decision certainty (Study 1: P < .001, ${\eta }_P^2$ = 0.05) and satisfaction (Study 1: P < .001, ${\eta }_P^2$ = 0.11; Study 2: P = .003, d = 0.29) were higher across all conditions after watching the consultation video, and certainty and satisfaction were lower in the control condition (Study 2: P < .001, ${\eta }_P^2$ = 0.05).

Discussion: Decision aids that explain preference-sensitivity and personal motives can be beneficial for improving people's feelings of being prepared and their perception of the decision-making process. To reach decision certainty and satisfaction, being well informed of one's options is particularly relevant. We discuss the implications of our findings for future research and the design of DAs.