Evaluating Care Integration between Pediatric Primary Care Providers and WIC Nutritionists for Early Obesity Prevention among WIC Mothers and Children - ABSTRACT The first 24 months of life set the foundation for healthy eating, sleep, and activity patterns that decrease the risk of obesity during childhood. More than one in ten infants in the U.S. are at risk of overweight, and one in five preschool-aged children are living with obesity. Young children living in rural contexts are more likely to experience poverty and limited access to nutritious and affordable foods, contributing to a higher prevalence of obesity and cardiometabolic diseases. To reduce health disparities among young children living in rural low-income contexts, there is a critical need for effective and scalable evidence-based interventions to support parents of young children starting early in life. Leveraging existing settings such as health care (standard well-child visits) and social care (Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) visits) for evidence-based intervention delivery is an effective way to reach the parents of young children living in low-income contexts, who have multiple visits with providers in these settings across the first 24 months of life. A series of reports from professional organizations including the American Academy of Pediatrics have called for solution-oriented approaches, moving away from siloed health care (primary care providers (PCPs)) and social care (WIC nutritionists) towards integrated care between these settings using health information technologies to enhance obesity prevention efforts and reduce health disparities. The goal of this research is to leverage existing care settings and use health information technologies to digitally integrate care and deliver an evidence-based responsive parenting intervention to mother-infant dyads living in rural low-income contexts who experience health disparities. This research will include a two-arm cluster randomized controlled trial to test the effectiveness of an integrated, patient-centered responsive parenting intervention on rapid infant weight gain and child BMI z-score at age 24 months (Aim 1), the effectiveness of the intervention on responsive parenting practices and child diet quality (Aim 2), an evaluation of whether the intervention is more or less effective in certain groups (Aim 3), and an evaluation of factors influencing effective implementation across health care, social care, and home settings (Aim 4). We hypothesize that compared to standard care (siloed PCP and WIC nutritionists care), children in integrated PCP-WIC nutritionist care will gain weight less rapidly from birth to 6 months and have a lower BMI z-score at age 24 months. Integrating care between trusted providers creates an opportunity to increase the time spent discussing child health in these often time-constrained settings and deliver consistent, integrated care on responsive parenting to inform scalable efforts to promote healthy child growth from the start and reduce health disparities among children living in rural low-income contexts.