PROJECT SUMMARY Approximately 20% of adolescents in the US have obesity, which is significant because of its many health consequences, including cardiometabolic disease leading to premature death. Treatment of obesity is particularly important for adolescents because obesity in this age group also increases the risk for lower income and lower educational attainment in adulthood. The cornerstone of all forms of obesity treatment is behavioral modification strategies that support daily dietary and physical activity change. Self-monitoring is a powerful behavioral tool that is grounded in Social Cognitive Theory. This theory states that greater self- awareness through proximate self-measurement improves self-efficacy, self-control, and self-reinforcement. Self-monitoring of weight through daily self-weighing (SW) at home has been found to be effective and safe for weight loss and maintenance in adults, particularly when there is external accountability for the home weights. Daily SW at home with accountability to clinic represents a scalable intervention that can be feasibly implemented into the clinical care for adolescents with obesity. However, daily SW at home has not been prospectively assessed in adolescent patients with obesity who are seeking obesity treatment. The objective of this proposal is to evaluate the feasibility, acceptability, safety, and estimate the effect on weight of daily SW at home, integrated with the electronic health record (EHR) and clinical care of adolescents with obesity. I will: 1) Use mixed methods to determine adolescent and parent perspectives on daily weighing on smart scales connected to the EHR as a tool for adolescents with obesity who are seeking weight loss treatment; 2) Determine clinician and clinic staff perspectives on daily weighing on connected to the EHR; and 3) Conduct a randomized, clinic-based pilot study to compare the feasibility, acceptability, safety, and estimate the effect size of three conditions in a weight management clinic for adolescents with obesity: a) usual care, b) usual care + daily SW at home on a simple scale, and c) usual care + daily SW at home on a smart scale that is connected to clinic (with individualized feedback to the patient). I will prospectively and serially assess mood, body image, stress, weight management practices, and disordered eating behaviors. This project will generate critical preliminary data to inform the design of a larger study (R01) that fully evaluates safety and efficacy of daily SW at home, with and without regular external accountability from clinic, in adolescents with obesity. Completing this K23 training program will allow me to establish skills in mixed methods, epidemiologic methods and intervention design, and foundational skills in implementation of digital technology, as well as lay the groundwork for leading novel and high-impact obesity studies. The multidisciplinary mentorship during this career development award will prepare me to become ...