A COSMIN Systematic Review of Transition Readiness Assessment Tools for Adolescents with Type 1 Diabetes

<b>Background</b>: Diabetes in youth, specifically type 1 diabetes (T1D), is an increasing global health concern. As prevalence rises, a growing number of adolescents are required to transition from pediatric to adult healthcare services. This phase is recognized as a particularly critical and high-risk period, during which emerging adults with T1D must exhibit advanced self-management skills to maintain optimal outcomes. When transition support is inadequate, the process is frequently associated with deterioration in glycemic control, higher rates of hospitalization, and significant psychological distress. <b>Methods</b>: A systematic review was conducted in accordance with PRISMA guidelines to identify and evaluate instruments that assess transition readiness in adolescents with diabetes, focusing on their psychometric properties. Five electronic databases (PubMed, CINAHL, Embase, APA PsycInfo, and Web of Science) were searched. Methodological quality and measurement properties were appraised using the updated 2024 COSMIN Guidelines. <b>Results</b>: Eleven studies were included, examining 10 distinct instruments. Overall, psychometric evidence was promising but limited. Only the "On TRAck" instrument demonstrated moderate-quality evidence with acceptable feasibility and reliability. Other tools showed partial support for validity, reliability, and responsiveness, but presented methodological limitations. <b>Conclusions</b>: Interest in diabetes-specific tools to assess transition readiness is growing, yet their psychometric robustness remains limited. Further research is needed to develop and validate instruments with stronger methodological rigor. Future efforts should focus on longitudinal performance and predictive validity to enhance their applicability in clinical practice and ultimately improve outcomes during transition.