Autism Secondary Data Analysis Program - PROBLEM. Despite widespread adoption of the medical home model, significant gaps persist in understanding its effectiveness for children with autism spectrum disorder (ASD), particularly regarding service coordination and early intervention access. Current measurement tools, including the NSCH Medical Home measure, show inconsistent reliability across, hampering efforts to evaluate and improve implementation. This research addresses MCHB Strategic Research Issues #2 (health equity in access) and #4 (service system integration), focusing on optimizing medical home measurement and implementation for enhanced service coordination. GOALS AND OBJECTIVES. Our primary goal is to enhance medical home effectiveness for children with ASD by validating measurement tools and identifying crucial elements of successful service coordination. We will accomplish this through five objectives: (1) evaluating the NSCH Medical Home measure's psychometric properties, (2) determining relationships between medical home components and early intervention access, (3) identifying system-level facilitators of service coordination, (4) developing evidence-based implementation recommendations, and (5) creating practical tools for healthcare providers. PROPOSED DATA SETS AND TARGET POPULATION. This study utilizes the National Survey of Children's Health (NSCH) dataset from 2016-2023, analyzing responses for children aged 0-17 years with ASD diagnoses. The research employs structural equation modeling with appropriate survey weights and stratification rules, incorporating both cross-sectional and validation analyses. The target population includes demographically diverse children with ASD across the United States, with particular attention to traditionally underserved communities. PRODUCTS. Project findings will be strategically disseminated through multiple channels to maximize impact. We will present at key maternal and child health conferences (CityMatch, AMCHP) and the International Meeting for Autism Research (INSAR), facilitating direct engagement with practitioners and policymakers. Publications will target high-impact journals including Academic Pediatrics and Maternal and Child Health Journal. Strategic partnerships with Autism Speaks and University Centers for Excellence in Developmental Disabilities (UCEDDs) will translate findings into actionable family support strategies. Deliverables include a validated measurement tool, best practice guidelines, policy briefs, and an interactive web-based toolkit for healthcare providers. EVALUATION. Our comprehensive evaluation strategy combines monthly monitoring, dual-stream performance measurement, systematic program evaluation, and continuous quality improvement. We track key indicators through the NSCH data, focusing on medical home measurement validation and service access analysis. Regular team reviews, secure data management through Stata, and external statistical validation ensure rigorous assessment of project outcomes. Deliverables include technical reports, peer-reviewed publications, and evidence-based policy recommendations. KEY TERMS: Content: Medical Home, Autism Spectrum Disorder, Service Coordination, Early Intervention, Healthcare Access, Quality Measurement, Systems Integration, Care Coordination, Family-Centered Care, Health Equity Targeted Populations: Children with Special Health Care Needs, Autism Spectrum Disorder, Underserved Communities, Rural Populations, Urban Populations, Racial and Ethnic Minorities Age Ranges: Infants (0-11 months), Toddlers (1-2 years), Preschool Children (3-5 years), School-Age Children (6-11 years), Adolescents (12-17 years)