We defined AUD from the inpatient register, which covers the young adult period for all three cohorts, using ICD codes for alcohol abuse and related disorders as described elsewhere (11). Briefly, these include codes for alcohol related disorders such as abuse and dependence (F10), alcoholic liver disease (K70), alcohol induced pancreatitis (K85.2 and K86.0), and toxic effects of alcohol (T51), among other diagnoses. The current analyses focus on AUD during young adulthood (between ages 19–24).