Incidence of type 1 diabetes mellitus diagnosed before age 20 years in Canterbury, New Zealand over the last 30 years.

This study examined the epidemiological characteristics of type 1 diabetes mellitus (DM) presenting in Canterbury, New Zealand, between 1970 and 1999. All patients with type 1 DM aged 0-19 years at diagnosis within the Canterbury geographical region were either admitted to the regional hospital or seen acutely as outpatients in clinics at the same institution. Primary ascertainment of incident cases, through notification by the attending physician or paediatrician, began prospectively in 1982.