Development of a Virtual Transition Program for Adolescents and Young Adults With Type 1 Diabetes: Three-Stage User-Centered Design Study.

Background: Adolescents and young adults (AYAs) with type 1 diabetes (T1D) face a heightened risk of care gaps and preventable complications during the transition from pediatric to adult care. AYAs from low-income families are more likely to experience poor outcomes. Care guidelines for T1D now recommend a transition program beginning several years prior to anticipated independence. However, existing transition programs often require substantial resources, limiting their scalability and accessibility. Objective: We used a human-centered design approach to develop and refine a low-cost, virtual intervention to support T1D transitions among publicly insured AYAs. Methods: Guided by the "3I" model (inspiration, ideation, implementation) of IDEO, we conducted semistructured interviews with 26 providers and staff across 4 University of California medical centers to identify challenges and opportunities for improving transition care. We then completed customer discovery interviews with 36 adopters and influencers, including AYAs, endocrinologists, and diabetes educators, to identify priorities and needs and create value propositions. The resulting intervention was tested with 3 cohorts (n=25) of publicly insured AYAs aged 17 to 21 years receiving pediatric diabetes care at an academic medical center. The intervention consisted of two 75-minute virtual group sessions led by a diabetes educator and peer mentors with lived experience. Feasibility, acceptability, and appropriateness were assessed via validated surveys and qualitative interviews. Results: Core functions of the intervention included education and discussion on "adulting with diabetes" and navigating the health care system, interactive creation of a transition plan, mentors sharing their experiences with diabetes, open discussion among peers, opportunities to ask questions, and provision of resources based on individual needs. Facilitators and mentors reported high feasibility (mean 4.25, SD 0.52) and appropriateness (mean 4.43, SD 0.53). Qualitative interviews highlighted peer support and lived-experience mentorship as core drivers of engagement. Attendance was highest among participants enrolled closer to session dates. Participant feedback informed ongoing adaptations to content and delivery across cohorts, including timing of the intervention, use of the chat function, multiple text reminders before intervention sessions, and specific topics of interest. Conclusions: This human-centered virtual transition intervention addressed priorities identified by AYAs, peer mentors, and clinicians, including peer support, judgment-free discussion, and self-advocacy. While engagement and attendance varied across cohorts, findings support further refinement and evaluation of the intervention in diverse settings.