Examining the impacts of pharmacy-based preventive services (PPS) in pediatric populations - Preventive health care, including screenings, anticipatory guidance, counselling, and clinical and behavioral interventions traditionally delivered in the medical home, is key to optimizing child and adolescent health and development. Many states now allow pharmacists to offer some preventive services in retail pharmacies. The delivery of pharmacy-based preventive services (PPS) is regulated at the state level, and over the past fifteen years many states have gradually allowed for younger age groups to receive care in pharmacies. These policy expansions were motivated by the desire to address the projected shortage of primary care physicians and supported by evidence that PPS improved access and outcomes in older populations. What works for adults may not work for kids, however, and there are major gaps in knowledge about the real-world impacts of PPS policies on child and adolescent health outcomes. On one hand, it is possible that PPS policies have provided new avenues for accessing preventive services, which could lead to increased service utilization. On the other hand, it is possible that offering PPS simply displaces preventive care from the medical home to pharmacy settings, which would not lead to a change in overall service utilization and could potentially, as some leading pediatricians have argued, put children at risk of missing well-child care visits. Given the importance of preventive care in advancing children’s health, and addressing the growing burden of childhood chronic disease, there is an urgent need to quantify whether PPS policies have impacted rates of well-child care visits. In this national study, we will make use of significant cross-state variation in PPS policies as well as policy changes over time that differentially affect birth cohorts within the same state to determine whether PPS policies are helpful, hurtful, or have no impact on pediatric preventive care outcomes, overall and within populations less likely to receive preventive health care. Using best practices from legal epidemiology, we will first develop a comprehensive, longitudinal database of variables relating to states’ policies regarding PPS for children and adolescents from 2013-2026 (Aim 1). We will then analyze a national all-payer pharmacy claims database from Symphony Health to quantify the volume of pediatric preventive services administered in pharmacy settings across the U.S., including whether there has been a differential impact by rurality, payer type, and area-level economic conditions (Aim 2). Finally, through linking with National Survey of Children’s Health (NSCH) data, we will quantify the impact of PPS policies on rates of well-child and well-adolescent care (Aim 3), including testing whether effects vary by rurality, payer type, or family income. The results from this study will provide a comprehensive picture of the real-world impacts of PPS, expanding a very limited scope of evidence regarding PPS for children and adolescents. We will determine the magnitude and directionality of PPS policies' impact on pediatric preventive care delivery. Our findings will provide timely empirical evidence on the effects of PPS that have the potential to inform future efforts around preventive care delivery for children and adolescents.