Interventions to support shared decision making for medication therapy in long term conditions: A systematic review

1) To examine the effectiveness of interventions to support shared decision making (SDM) for medication therapy in long term conditions on patient outcomes; 2) to identify characteristics of SDM interventions that are associated with positive patient outcomes.

A systematic search for randomized controlled trials up to February 2019. A best evidence synthesis was performed. Intervention characteristics that are likely to be associated with positive patient outcomes were identified using descriptive statistics.

Twenty-five articles reporting 23 studies were included. Seventeen patient outcomes were assessed using a variety of measurement instruments. There was evidence for a positive effect of SDM interventions on risk estimation and involvement in decision making. Evidence for no effect was found on four outcomes (e.g. medication adherence) and conflicting evidence on ten outcomes (e.g. decisional conflict). Electronically delivered SDM interventions and those comprising value clarification exercises were likely to be associated with positive patient outcomes.

There is a lack of evidence for a positive effect of SDM interventions on the majority of patient outcomes. The mode and content of SDM interventions seem to affect patient outcomes.

There is a need for standardization of patient outcomes and measurement instruments to evaluate SDM interventions.