**Background:** The transition from paediatric to adult care is a high-risk period for youth with type 1 diabetes (T1D), marked by deterioration in glycaemic management and increased acute complications. Many existing transition interventions are limited by cost, scalability, and lack of youth engagement. Text messaging offers an accessible, acceptable, and cost-effective modality. The authors co-designed Keeping in Touch (KiT), an automated text message-based intervention, with adolescents, emerging adults, and paediatric and adult T1D providers to deliver tailored transition support.
**Methods:** This is a multisite, parallel-group, two-arm, 1:1 allocation ratio, superiority RCT conducted at six paediatric diabetes clinics in Ontario and Quebec, Canada (four in Ontario: The Hospital for Sick Children, Children's Hospital of Eastern Ontario, Trillium Health Partners, Oak Valley Health; two in Quebec: Montreal Children's Hospital/MUHC and CHU Sainte-Justine). Recruitment started January 2023 and will continue until end of June 2024. The intervention period is 12 months after recruitment is complete.
INCLUSION CRITERIA
adolescents with T1D aged 17–18 years, within 4 months of their planned final paediatric clinic visit, able to communicate in English or French, with a mobile device capable of text messaging and a valid email address. Exclusion criteria: inability to carry out diabetes care independently due to intellectual/neurocognitive disability, non-residents of Ontario or Quebec, planning to move provinces within 12 months, or enrolled in another trial involving text messaging or a diabetes intervention continuing beyond the final paediatric visit.
A total of 183 participants will be randomised 1:1 stratified by site using computer-generated random block sizes. The sample size provides 80% power with α=0.05, assuming SD of 1.6 for self-efficacy, 6 degrees of freedom for adjustment, and 20% dropout.
The KiT intervention delivers tailored T1D transition support via text messages over 12 months, hosted by Memotext. It has three key functions: (1) personalised T1D educational messages based on responses to a transition readiness assessment (READDY tool) and participant topic choice; (2) care coordination including appointment reminders, lab test reminders, and information about adult clinics; and (3) question-and-answer where participants can text T1D-related questions and receive replies from a validated bank of resources. Participants can choose English or French and can pause messages at any time. The control arm receives usual care plus text messages with links to outcome surveys.
**Key Results:** This is a protocol paper; no results are reported. The primary outcome is diabetes self-efficacy at 12 months measured by the SEDM scale (validated in adolescents with T1D, α=0.90). Secondary outcomes measured at baseline, 6 months, and 12 months include: transition readiness (READDY tool), diabetes-related stigma (BDA Stigma subscale), self-reported HbA1c, time in range and time in low (for CGM users using ≥80% of the time in preceding 14 days), time between final paediatric and first adult diabetes visit, diabetes-related hospitalisations and ED visits (from provincial administrative databases: ICES in Ontario, Med-Echo and RAMQ in Quebec), and cost of implementation. HbA1c will also be abstracted from the chart at baseline.
Analysis will be intention-to-treat using ANCOVA for the primary outcome, adjusting for baseline self-efficacy, baseline HbA1c, and material deprivation quintile. Secondary analyses will use ANCOVA and logistic regression. A secondary as-treated analysis will be conducted by engagement level. A descriptive cost analysis from the healthcare payer perspective will follow CADTH guidelines and CHEERS reporting.
**Clinical Implications:** If KiT is found to improve diabetes self-efficacy and secondary outcomes, it would provide an evidence-based, scalable, low-cost digital intervention to support youth during the vulnerable transition from paediatric to adult T1D care. The automated nature of KiT addresses limitations of prior interventions that require healthcare provider support, enhancing scalability. The co-design approach with youth and providers aims to ensure acceptability and engagement. The study's conduct across two provinces and two languages (English and French) will support generalisability. Next steps include assessing cost-effectiveness and exploring adaptation for other childhood chronic illnesses.