Abstract
Nonadherence is the Achilles' heel of effective psychiatric treatment. It affects the resolution of mental health symptoms and interferes with the assessment of treatment response. The meaning of the term adherence has evolved over time and is now associated with a variety of definitions and measurement methods. The result has been a poorly operationalized and nonstandardized term that is often interpreted differently by providers and patients. Drawing extensively from the literature, this article aims to (1) describe changes in the concept of adherence, drawing from the mental health treatment literature, (2) present a more comprehensive definition of adherence that recognizes the role of patient-provider transactions, (3) introduce dynamic adherence, a six-phase model, which incorporates the role of transactional processes and other factors that influence patients’ adherence decisions, and (4) provide recommendations for providers to improve adherence as well as their relationships with patients.