Development and evaluation of the Measure of Drug Self-Management

Stacy Cooper Bailey,1 Izabela E Annis,1 Daniel S Reuland,2 Autumn D Locklear,1 Betsy L Sleath,1 Michael S Wolf3 1Division of Pharmaceutical Outcomes and Policy, Eshelman School of Pharmacy, 2Department of Medicine, Division of General Internal Medicine and Clinical Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 3Health Literacy and Learning Program, Division of General Internal Medicine, Feinberg School of Medicine at Northwestern University, Chicago, IL, USA Background: Current adherence scales often fail to assess the full spectrum of behaviors associated with safe and appropriate drug use and may be unsuitable for patients with limited health literacy. We sought to develop and evaluate a comprehensive yet brief Measure of Drug Self-Management (MeDS) for use in research and clinical settings among diverse patient groups.Methods: Expert opinion, literature reviews, and interviews with patients and providers were utilized to create and revise potential items. Item performance testing was then conducted among 193 adult English-speaking patients with hypertension and diabetes. Factor analysis was used to inform item selection. Reliability was assessed via calculations of internal consistency. To assess construct and predictive validity, MeDS scores were compared with scores from the 8-item Morisky Medication Adherence Scale and relevant clinical measures (HbA1c, blood pressure, and low-density lipoprotein cholesterol).Results: The MeDS demonstrated adequate internal consistency with a Cronbach’s α of 0.72. The MeDS was significantly correlated with the Morisky Medication Adherence Scale (r= -0.62; P