To what extent is treatment adherence of psychiatric patients influenced by their participation in shared decision making?

RATIONALE Nonadherence to prescribed medications is a significant barrier to the successful treatment of psychiatric disorders in clinical practice. It has been argued that patient participation in shared decision making improves adherence to treatment plans. PURPOSE To assess to what extent treatment adherence of psychiatric patients is influenced by the concordance between their preferred participation and their actual participation in decision making. MATERIALS AND METHODS A total of 967 consecutive psychiatric outpatients completed the Control Preference Scale twice consecutively before consultation, one for their preferences of participation, and the other for the style they had usually experienced until then, and the eight-item self-report Morisky Medication Adherence Scale 8. RESULTS Most psychiatric outpatients preferred a collaborative role in decision making. Congruence was achieved in only 50% of the patients, with most mismatch cases preferring more involvement than had been experienced. Self-reported adherence was significantly higher in those patients in whom there was concordance between their preferences and their experiences of participation in decision making, regardless of the type of participation preferred. CONCLUSION Congruence between patients' preferences and actual experiences for level of participation in shared decision making is relevant for their adherence to treatment.