Cohort members were followed from date of recruitment or 1 January 1995 (start of the NDR) (whichever was last) until date of diabetes, as recorded in NDR, death, emigration, or 27 June 2006 (whichever came first).
For siblings we computed time from January 1, 1977, or the index date of the respective patient or population control, whichever came last, until date of death, emigration, loss to follow-up, or December 31 , 2009 whichever came first.
In other cases, the progression-free survival period lasted until the date of recurrence or the date of the patient's death.
The cohort members were followed from date of birth or 1 January 1969, whichever occurred last, until the date of diagnosis of type 1 diabetes according to the Swedish versions of International Classification of Disease (ICD-8: 250, 1969 1986; ICD-9: 250, 1987–1996; ICD-10: E19971997 and onwards), emigration, death or end of follow-up (31 December 2009), whichever occurred first.
We calculated person-years at risk of autism and ADHD among individuals with a family history of AUDs (either biological or adoptive parents with AUDs) from the date of birth, immigration, or 1 January 1987, whichever came last, until the date of diagnosis of autism or ADHD, death, emigration, or the end of the study period (31 December 2010), whichever came first.
We calculated person-years at risk among individuals with lactose intolerance from the date of birth, immigration, or 1 January 1961, whichever came last, until the date of diagnosis of cancer, death, emigration, or the end of the study period (31 December 2010), whichever came first.
Follow-up lasted until the date of diagnosis, death, emigration, a child's 16th birthday, or 31 December 2008.
We classified exposure of drugs into four mutually exclusive time windows: current use (recent prescription lasted until index date or ended in the 30 days prior); recent (finished between 31 and 365 days), past (finished more than 365 days), and never use (no recorded use at any time prior to index date).
Time values for PFS and OS estimates were assessed starting on the date of the last allo-SCT until date of relapse/last follow-up and for OS until death independent of the cause or last follow-up.
Time to distant relapse (TTDR) was measured from date of last treatment received until date of first relapse or else censored at the date of last follow-up.
Patients were followed-up from diagnosis until death or last date of contact for a median of 88 months (mean 94 months; range 7 222).
