AIM: The study aimed to identify active intervention components to improve glucose sensor time in range (TIR
70-180 mg/dL [3.9-10.0 mmol/L]) by ≥5 % among adolescents and young adults (13 to 20 yrs) with type 1 diabetes and above recommended glycated haemoglobin (HbA1c ≥ 7.5 % [≥ 58 mmol/mol]), regardless of current insulin therapy. METHODS: The 6-week optimisation trial used a 2 RESULTS: The main effects, as measured by the mean difference (95 % CI) in TIR from baseline to 4 weeks, were: CGM, 3.3 (-8.8, 15.4) percentage points
sleep extension, -7.2 (-19.0, 4.6) percentage points
snacking support, 0.9 (-11.8, 13.5) percentage points
values-guided self-management, 6.1 (-7.5, 19.7) percentage points. CONCLUSIONS: The values-guided self-management was the only 'active' component. Conclusions about the less impactful intervention components are limited due to disruptions in research activities from the COVID-19 pandemic. Future work will address other candidate intervention components.