PROJECT SUMMARY/ABSTRACT: Congenital heart defects (CHD) affect over 2.4 million individuals in the U.S and generate $6.1 billion in annual healthcare costs. Avoidance of tobacco is vital to mitigate CHD survivors’ risk for acquired cardiovascular complications, but the youth e-cigarette (“vaping”) crisis exposes the growing and vulnerable population of adolescents (“teens”) with CHD to potential vaping-related harms and significantly increases risk for conventional cigarette use. Interventions to prevent vaping among teens with CHD are critically needed, but no existing programs are sufficient for this at-risk group. Dr. Fox’s TL1 fellowship research showed that 31% of teens with CHD are susceptible to vaping and identified perceived stress and poor disease knowledge as potential risk factors, but existing programs do not address these considerations. The proposed research will generate and evaluate the first vaping prevention intervention tailored for teens with CHD. Aim 1: Adapt curriculum from an evidence-based, classroom-delivered vaping prevention intervention to include critical stress management and disease knowledge modules in a mobile Health (mHealth) format for teens (12-18 years) with CHD. Intervention adaptation/refinement will occur via: 1) focus groups with key stakeholders (teens with CHD, parents, cardiologists) to understand intervention preferences, and 2) a single-arm pilot trial of the adapted mHealth intervention (N=16) with follow-up focus groups to gather information for refinement. Aim 2: Evaluate the feasibility/acceptability of the mHealth intervention via a pilot randomized clinical trial (RCT; N=72). Exploratory Aim 3: Explore the preliminary efficacy of the mHealth intervention for indicators of vaping prevention (vaping-related efficacy, perceived vaping outcomes, e-cigarette knowledge). These aims directly align with Dr. Fox’s career goal of becoming an independent clinician-scientist with expertise in behavioral RCTs and scalable disease self-management interventions for transition-aged teens with CHD. To achieve this goal, Dr. Fox requires advanced training in the following areas: 1) behavioral intervention science to design and optimize interventions that can be implemented on a public health level, such as mHealth modalities, 2) RCT methodology and analysis to rigorously evaluate behavioral interventions for efficacy and effectiveness, and 3) CHD disease self- management and healthcare for transition-aged teens to incorporate unique factors of living with CHD into tailored interventions. The career development plan involves didactic and applied training and leverages expert multidisciplinary (public health, clinical/quantitative psychology, cardiology) mentorship from The Abigail Wexner Research Institute at Nationwide Children’s Hospital, one of the worlds’ fastest growing pediatric research centers, its academic affiliate The Ohio State University, and the Fred Hutchinson Cancer Research Center. This K23 prop...