PROJECT SUMMARY While ~25% of school-age children with type 1 diabetes (T1D) achieve an HbA1c of <7.5%, the majority of school-age children do not and are at a higher risk for T1D-related complications. Achieving optimal T1D self- care is currently the only direct pathway to better HbA1c and even with the addition of modern therapeutic modalities (e.g., hybrid closed loop), T1D self-care is a complex, time-consuming, and relentless task. School- age children need support from their parents to effectively manage T1D and therefore both parents and youth with T1D are vulnerable to Diabetes Distress (DD). Presently, the American Diabetes Association (ADA) Standards of Care recommend assessment of DD during routine diabetes clinic visits in youth and their caregivers starting when youth are ~8-years-old. Unfortunately, while DD screening may be an ADA Care Standard, there are no practical and evidence-based screen-to-treat programs for clinics to adopt to meet this Standard of Care. We submit this new R01 in response to RFA-DK-19-021, Treating Diabetes Distress to Improve Glycemic Outcomes in Type 1 Diabetes. Our objective is to test the feasibility and acceptability of a novel, practical, and scalable screen-to-treat program for DD in school-age children and their parents (called Remedy to Diabetes Distress [R2D2]) and to test the initial efficacy of R2D2 to reduce DD to improve children's glycemic control. Our specific aims are: 1) Define and iteratively refine our new screen-to-treat program (R2D2) for DD in school-age families in order to maximize feasibility and acceptability to stakeholders, and 2) Establish initial efficacy of R2D2 to reduce parent and child DD to improve child glycemic control. To enhance scientific rigor, we will use the ORBIT Model for Behavioral Intervention Development to guide our study design. The ORBIT Model proposes a phased approach using a series of small, cost-effective studies to determine clinically- meaningful targets and to test a treatment's acceptability and initial efficacy before embarking on a large clinical trial. For ORBIT Phase 1a: Define, we will conduct a brief longitudinal study to establish cut-points for clinically relevant DD in parents and school-age children, engage clinic Quality Improvement teams to develop a practical clinic-based screening approach, and use crowdsourcing techniques to obtain family input on a new mHealth treatment. For ORBIT Phase 1b: Refine, we will test implementation of our R2D2 screening program across multiple clinics and we will conduct a small trial to identify an initially efficacious and practical mHealth treatment delivery approach for R2D2. Finally, for ORBIT Phase 2a, we will continue to screen for DD in clinic and recruit families who report clinically relevant DD into a Proof of Concept Pilot to examine whether ameliorating parent and/or child DD leads to improved child glycemic control. We believe our study optimally responds to the FOA because our: 1-research ...