The Mental Health Parity and Addiction Equity Act evaluation study: Impact on specialty behavioral health utilization and expenditures among “carve-out” enrollees

• Published in: Journal of health economics 2016-12, Vol.50, p.131-143
• Main Authors: Ettner, Susan L., M. Harwood, Jessica, Thalmayer, Amber, Ong, Michael K., Xu, Haiyong, Bresolin, Michael J., Wells, Kenneth B., Tseng, Chi-Hong, Azocar, Francisca
• Format: Article
• Language: English
• Subjects: Addictions; Adult; Behavioral health; Equity; Expenditures; Federal legislation; Female; Health administration; Health behavior; Health care expenditures; Health Expenditures; Health insurance; Health Status Disparities; Hospitalization; Humans; Insurance; Insurance benefits; Interim; Male; Mental disorders; Mental Health; Mental Health Services - economics; Mental Health Services - utilization; Middle Aged; Parity; Patients; Psychiatry; Regression analysis; Regression models; Service provision; Statistical analysis; Studies; Time series; United States; Utilization
• ISSN: 0167-6296; 1879-1646
• DOI: 10.1016/j.jhealeco.2016.09.009

•Among behavioral healthcare “carve-out” enrollees, MHPAEA had mixed effects on use.•Even when statistically significant, associations tended to be modest in magnitude.•Thus MHPAEA did not have a notable impact on behavioral healthcare treatment per se.•Stronger evidence was found that costs shifted from patients to health plans.•Thus the primary impact among carve-out patients may have been reduced patient financial burden. Interrupted time series with and without controls was used to evaluate whether the federal Mental Health Parity and Addiction Equity Act (MHPAEA) and its Interim Final Rule increased the probability of specialty behavioral health treatment and levels of utilization and expenditures among patients receiving treatment. Linked insurance claims, eligibility, plan and employer data from 2008 to 2013 were used to estimate segmented regression analyses, allowing for level and slope changes during the transition (2010) and post-MHPAEA (2011–2013) periods. The sample included 1,812,541 individuals ages 27–64 (49,968,367 person-months) in 10,010 Optum “carve-out” plans. Two-part regression models with Generalized Estimating Equations were used to estimate expenditures by payer and outpatient, intermediate and inpatient service use. We found little evidence that MHPAEA increased utilization significantly, but somewhat more robust evidence that costs shifted from patients to plans. Thus the primary impact of MHPAEA among carve-out enrollees may have been a reduction in patient financial burden.