Findings demonstrate that academic performance did not differ among young people hospitalized with type 1 diabetes mellitus (T1D) vs matched peers not hospitalized with diabetes. Absence of school performance decrements in students with T1D may be explained by improved glucose control and T1D management. However, there was a higher risk of not completing high school in females hospitalized with T1D. Potential links of this elevated risk, with attention to T1D and psycho-social management, need to be investigated.

• In this population-level matched case-comparison study, researchers compared scholastic performance and high school completion in young people hospitalised with T1D vs matched peers not hospitalised with diabetes.

• Absence of a higher risk of not achieving the national minimum standard was seen in young females and males hospitalised with T1D vs peers for numeracy [adjusted relative risks (ARR): 1.19 and ARR: 0.74] or reading (ARR: 0.98 and ARR: 0.85), respectively.

• Young T1D hospitalised females were found to have a higher risk of not completing year 11 (ARR: 1.73) or 12 (ARR: 1.65) than peers, while hospitalised T1D males did not.