Project Summary/Abstract The proposed R01 aims to understand the effect of state telehealth policy changes on patient- reported mental health care and outcomes. During recent years, there was a significant 25% increase in depression and anxiety prevalence, with more than 10% of adults reporting being unable to receive mental health counseling. Certain populations experienced more pronounced effects, including worsened mental health symptoms, high unemployment, and limited access to care. Mental health care access remains insufficient and faces multiple challenges, particularly for Medicaid patients. Telehealth can effectively connect patients and providers via electronic platforms that enable video visits, specialist consultation, etc., to bridge gaps in mental health care access. Yet, telehealth implementation remains limited in many areas, including clinics serving patients with reduced access to technology and with poor digital literacy. Substantial variation exists across states that expanded telehealth policies or not, including Medicaid programs. Recent expansions in some, but not all, state telehealth policies offer an opportunity to naturalistically examine their potential to improve mental health care and outcomes for all. Our Specific Aims are to: (1) characterize states’ telehealth policies and identify determinants of telehealth expansion; (2) examine the effects of state telehealth policy expansion on (a) increasing access to, use of, and expenditures related to mental health care and (b) improving mental health outcomes, functioning, and employment; and (3) understand key stakeholder perspectives of how state telehealth policy expansion influenced mental health services delivery, with a focus on improving care in resource-limited settings. In Aim 1, we will use legal research to identify state policies that expanded telehealth (e.g., Medicaid reimbursement, private payer laws, professional licensure requirements) and will examine explanatory state factors (e.g., broadband access). In Aim 2, we will leverage variation in telehealth policy across states to use a difference-in-differences approach to predict effects on outcome measures using two nationally representative surveys of individuals – the longitudinal Medical Expenditure Panel Survey (MEPS) and the cross-sectional Household Pulse Survey. Finally in Aim 3, we will use a positive deviance approach to select 6 “high” and 6 “low” telehealth expansion states. From there, we will conduct interviews with 12 primary care and 12 mental health state association leaders and focus groups with clinicians, staff, and administrators representing 12 states balanced by rurality. The overall study goal is to better understand the effect of state policy changes around telehealth on patient-reported mental health care access, costs, symptoms, and functioning.