Of the original cohort of 1,037 individuals, 931 study members (89.8%) were included in our analyses. Similar to a previously described analysis of administrative records in this cohort, we excluded 16 study members who died before reaching adulthood, 35 who were either long-term missing to the study or refused administrative records search, and 46 who no longer resided in NZ and thus would not be expected to accumulate service usage in NZ (Caspi et al., 2016). Additionally, 3 study members for whom childhood conduct problems could not be assessed were excluded.
