A multi-theoretical approach to linking medication adherence levels and the comparison of outcomes

Background: There has been relatively little theoretical research exploring the cognitive complexity of how patients decide the level to which they adhere to prescribed regimens. Objectives: To integrate various psychosocial theories into a conceptual framework to review how patients relate their medication use behavior to therapeutic outcomes and how such relationships affect subsequent medication use. Methods: Key psychosocial theories were reviewed involving health beliefs and medication adherence, individual control, and how individuals might compare outcomes with expectations and alternatives. These concepts were integrated into one larger multilevel explanatory model, the Dynamic Exchange Model for Medication Adherence Levels and Comparison of Outcomes (DEMMALCO), explaining how patients might attribute outcomes related to their medication use and choose future actions based on expectations and alternatives available. Key assumptions of the model were also identified. Results: DEMMALCO indicates that patients make initial attributions of their control over their illness, which affects their subsequent adherence to their regimens. The model suggests that patients actively compare their treatment outcomes with their expectations about outcomes and the outcomes that are related to their best alternative. They are thought to reassess how their control in treatment was related to those outcomes and subsequently modify their adherence behavior based on the presence or absence of resources. Conclusions: Strengths and limitations of the model are noted. DEMMALCO may help inform researchers and clinicians on new ways to conceptualize, monitor, and change medication adherence behavior. (C) 2010 Elsevier Inc. All rights reserved.