PROJECT SUMMARY/ABSTRACT The purpose of this proposed K01 Mentored Research Career Development Award is to support the applicant in advancing and maximizing her research skills in order to launch an independent research career in the dissemination and implementation of evidence-based substance use treatment for safety net populations. Safety net populations, especially individuals who are publicly insured by Medicaid and the Children’s Health Insurance Program (CHIP), have been disproportionately impacted by the U.S. opioid epidemic. Despite a significant need for treatment, lifesaving medications for opioid use disorder (MOUD) are underused by this population. Low MOUD use is driven by a myriad of misaligned federal, state, Medicaid/CHIP agency and managed care organization benefit and utilization management policies informed by varying levels of evidence. Federal policy requires all three MOUD (i.e., buprenorphine, methadone, naltrexone) be included as mandatory Medicaid state plan benefits, but not all states have complied, and the Centers for Medicare and Medicaid Services acknowledges that enforcing coverage is not feasible. Even when Medicaid/CHIP agencies cover all three MOUD, they can restrict access via preferred drug lists, fail-first, prior and re-authorization requirements – thus imposing potentially life-threatening care delays on beneficiaries. Managed care organizations (MCOs) that many state agencies contract to administer benefits can enact additional utilization management policies that limit MOUD access. Research is needed to promote Medicaid/CHIP and MCO policymakers’ use of scientific evidence when designing MOUD benefits. Under the mentorship of Dr. Gregory Aarons (sponsor and mentor) and an expert mentoring team, the applicant will pursue training in: (1) survey design, (2) multivariate statistical analysis, including latent class analysis and finite mixture modeling, (3) policy dissemination strategy development, including packaging and communicating evidence for policymakers, and (4) developing research partnerships with policy-relevant decision-makers. These training goals will facilitate accomplishing research aims to: (1) develop and administer a national survey to Medicaid/CHIP agency and MCO policymakers to identify determinants, mechanisms, and intermediaries that influence their evidence use behaviors; (2) empirically identify and describe distinct subgroups of Medicaid/CHIP agencies and MCOs based on their evidence use behaviors when designing MOUD benefits; (3) design and pilot test the acceptability, appropriateness and feasibility of dissemination strategies, tailored to each latent class, for promoting policymakers’ evidence-based decision-making regarding MOUD benefits. This proposal is aligned with NIDA’s strategic objectives to assess the impact of substance use disorder-related federal, state and systems policies on public health, and to identify strategic intermediaries and policy implementation strategie...