Telehealth Parity Laws and Depression Diagnosis Prevalence: Evidence from Staggered State Adoption

Abstract

Do state telehealth parity laws—which require private insurers to cover telehealth services—increase mental health care access? Using a difference-in-differences design exploiting the staggered adoption of telehealth parity laws across U.S.\ states adopting between 2012 and 2019, I estimate the effect on lifetime depression diagnosis prevalence (the share of adults ever told they have depression) using BRFSS data. I employ the heterogeneity-robust estimator of with not-yet-treated states as controls. Because the outcome panel begins in 2011, states adopting before 2012 (always-treated in the sample) do not contribute to identification; the analysis estimates effects for the 27 states adopting during 2012–2019. The overall average treatment effect on the treated is $-0.48$ percentage points (SE = 0.35), with a 95% confidence interval spanning $[-1.16, 0.20]$. This null finding suggests that telehealth parity laws alone may have had limited effects on mental health care access during the pre-COVID period, possibly due to implementation barriers, limited provider adoption, or the continued dominance of in-person care.