Federal parity law associated with increased probability of using out-of-network substance use disorder treatment services

Emma E. McGinty, Susan H. Busch, Elizabeth A. Stuart, Haiden A. Huskamp, Teresa B. Gibson, Howard H. Goldman, Colleen L. Barry

Research output: Contribution to journalArticle


The Paul Wellstone and Pete Domenici Mental Health Parity and Addiction Equity Act of 2008 requires commercial insurers providing group coverage for substance use disorder services to offer benefits for those services at a level equal to those for medical or surgical benefits. Unlike previous parity policies instituted for federal employees and in individual states, the law extends parity to out-of-network services. We conducted an interrupted time-series analysis using insurance claims from large self-insured employers to evaluate whether federal parity was associated with changes in out-of-network treatment for 525,620 users of substance use disorder services. Federal parity was associated with an increased probability of using out-of-network services, an increased average number of out-of-network outpatient visits, and increased average total spending on out-of-network services among users of those services. Our findings were broadly consistent with the contention of federal parity proponents that extending parity to out-of-network services would broaden access to substance use disorder care obtained outside of plan networks.

Original languageEnglish (US)
Pages (from-to)1331-1339
Number of pages9
JournalHealth Affairs
Issue number8
StatePublished - Jan 1 2015


ASJC Scopus subject areas

  • Health Policy

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