Presentation (CTI)

OBJECTIVES: Mental health benefits in the United States have historically been more restrictive than medical benefits. In October 2016, TRICARE implemented a comprehensive behavioral health parity reform to eliminate coverage limitations and expand provider availability. This study evaluated the reform's impact on ambulatory, inpatient, and emergency department (ED) mental health care utilization among active-duty service members (ADSMs) and their family members.
METHODS: Using Military Health System Data Repository records, we constructed a person-quarter panel spanning 2014-2024, comprising 61,569,925 quarters for 3,264,282 ADSMs and 58,857,372 quarters for 3,290,000 family members aged 5-64 years. Outcomes included ambulatory mental health visits, psychiatric hospitalization, and psychiatric ED encounters. Two-part segmented regression models estimated changes in care initiation and utilization intensity among users. Event-study analyses assessed dynamic effects and tested for anticipatory utilization changes.
RESULTS: Among ADSMs, the parity reform was associated with an immediate 11.5-percentage-point decrease in ambulatory mental health care initiation, followed by a 4.8-percentage-point increase per quarter thereafter (both p<0.001). Among family members, initiation declined by 1.1 percentage points immediately post-implementation but subsequently increased by 1.2 percentage points per quarter (both p<0.001). Ambulatory visit intensity increased by 0.11 visits per quarter among ADSMs (p<0.001) but showed no significant change among family members. The probability of psychiatric hospitalization rose by 0.5 percentage points for ADSMs and 1.1 percentage points for family members (both p<0.001). No significant effects were observed for psychiatric ED utilization. Event-study analyses revealed dynamic ambulatory care effects with no evidence of anticipatory behavior.
CONCLUSIONS: TRICARE's behavioral health parity reform increased ambulatory mental health care engagement and, among ADSMs, visit intensity, while also increasing the likelihood of psychiatric hospitalization without affecting ED utilization. Aligning benefit expansion with outpatient workforce capacity and clinic availability may be necessary to meet growing demand for mental health services.