Specialty health care,treatment patterns,and quality: the impact of a mental health carve-out on care for depression

OBJECTIVES: To assess the effect of a mental health carve-out on treatment patterns and quality of care for outpatient treatment of depression. DATA SOURCES: Outpatient and pharmaceutical claims from September 1993 through March 1997 for one large managed care organization in the Midwest that carved-out mental health and substance abuse benefits in September 1995. RESEARCH DESIGN: Using the treatment episode as the unit of analysis (n = 1,747), changes in treatment patterns associated with the change to a carve-out were evaluated. Logistic regression was used to assess whether in the postperiod a treatment episode was more likely to be treated with (1) an antidepressant and (2) a type and intensity of treatment with proven efficacy. To strengthen confidence in a causal relationship, I search for structural breaks in treatment patterns across a wide range of dates, assuming no a priori knowledge of the timing of the impact of the carve-out. RESULTS: I find the carve-out to be associated with an increase in the use of drug treatments. Although I find a decrease in the use of guideline-level treatment over the entire study period, there is an increase in the number of episodes treated with guideline-level treatment over what would be the case in the absence of the carve-out. CONCLUSIONS: The increase in the use of drug treatments suggests previous research that excluded these costs may have overestimated the savings attributable to carve-outs. Guideline-level care appeared to increase as a result of carve-out implementation suggesting the use of management and specialization to reduce costs is not antithetical to quality improvement.