Interventions to Enhance Medication Adherence in Chronic Medical Conditions

Approximately 20% to 50% of patients are not adherent to medical therapy. This review was performed to summarize, categorize, and estimate the effect size (ES) of interventions to improve medication adherence in chronic medical conditions.

Randomized controlled trials published from January 1967 to September 2004 were eligible if they described 1 or more unconfounded interventions intended to enhance adherence with self-administered medications in the treatment of chronic medical conditions. Trials that reported at least 1 measure of medication adherence and 1 clinical outcome, with at least 80% follow-up during 6 months, were included. Study characteristics and results for adherence and clinical outcomes were extracted. In addition, ES was calculated for each outcome.