Continuity of care in dual diagnosis treatment: definitions, applications, and implications.

OBJECTIVE: The goal of this work is to review the current literature on continuity of care in the treatment of people with dual diagnosis. In particular, this review set out to clarify how continuity of care has been defined, applied, and assessed in treatment and to enhance its application in both research and clinical practice. METHODS: To identify articles for review, the term "continuity" and combinations of "substance" and "treatment" were searched in electronic databases. The search was restricted to quantitative articles published in English after 1980. Papers were required to discuss "continuity" in treatment samples that included a proportion of patients with a dual diagnosis. RESULTS: A total of 18 non-randomized studies met the inclusion criteria. Analysis revealed six core types of continuity in this treatment context: continuity of relationship with provider(s), continuity across services, continuity through transfer, continuity as regularity and intensity of care, continuity as responsive to changing patient need, and successful linkage of the patient. Patient age, ethnicity, medical status, living status, and the type of mental health and/or substance use disorder influenced the continuity of care experienced in treatment. Some evidence suggested that achieving continuity of care was associated with positive patient and treatment-related outcomes. CONCLUSIONS: This review summarizes how continuity of care has been understood, applied, and assessed in the literature to date. Findings provide a platform for future researchers and service providers to implement and evaluate continuity of care in a consistent manner and to determine its significance in the treatment of people with a dual diagnosis.