Patient decision aids to support clinical decision making: evaluating the decision or the outcomes of the decision.

Decision aids (DAs) are tools to support patients make informed health decisions with their practitioner. They aim to improve patient knowledge of options, incorporate patient preferences and values, and increase patient involvement in health decision making. Increasingly, the debate about DAs concerns how they should be implemented in practice, with the view that DAs are superior to usual clinical care in facilitating health decisions. The authors challenge this view and suggest that DA research has focused on measures of decision process, leaving the effects on the outcome of the decision relatively unknown. It is still unclear in which conditions DAs are better for patient health and well-being than clinician-led decisions. The authors present a new randomized design to examine the effects of DA-supported patient choice on patient-centered outcomes to identify where DAs are best implemented in clinical practice. In this design, patients are randomized to 1 of 4 arms: intervention A, intervention B, choice of either intervention supported by a clinician, or choice of either intervention supported by a decision aid. Health and quality of life measured over the long term are presented as the primary outcomes. The authors propose that this design will allow the proper assessment of different modes of decision making.