The purpose of this study is to determine whether continuous glucose monitoring will improve glucose variability as measured by the coefficient of variation of glucose levels in very young children with T1D. The study adopts an open-label, multi-centre, multinational, prospective registry-based population cohort design contrasting CGM use to SMBG alone in young children with type 1 diabetes over 12 months.

The primary endpoint is the difference between treatment modalities (CGM vs SMBG alone) in glycaemic variability, measured as the coefficient of variation of glucose levels, during the 12 months observational period. Other Key edpoints include time in range 70-180 mg/dl, time below range 70 mg/dl and time above range 180 mg/dl.

Key inclusion criteria:

1. Age below 7 years of age (at inclusion)
2. Type 1 diabetes for at least 6 months
3. Insulin pump user for at least 3 months
4. Treated with rapid or ultra-rapid acting insulin analogue

Key exclusion criteria:

1. Physical or psychological disease likely to interfere with normal conduct of the study
2. Untreated coeliac disease or thyroid disease
3. Current treatment with drugs known to interfere with glucose metabolism
4. Subject/carer's severe visual impairment
5. Subject/carer's severe hearing impairment

Pre-school children below age of 7 years with type 1 diabetes (for at least 6 months) and treated with insulin pump fo at least 3 months.