The primary risk factor of interest was exposure to parental externalizing behavior. This was operationalized as a registration for AUD (as defined above); a registration for drug use disorder (also from the inpatient register), using ICD codes described elsewhere (27); or a registration for criminal behavior. Criminal behavior was identified by convictions in lower court for violent crime, property crime, or white collar crime (32). We refer to this composite measure as parental externalizing behavior (EB). Note that this measure likely represents relatively severe cases with high levels of EB due to its reliance on medical and criminal registrations; more moderate forms of externalizing behavior are unlikely to lead to such registrations. Parental EB was derived separately for each developmental period of interest (child age 0–6, 7–12, and 13–18; given the absence of defined ages corresponding to developmental periods, these ranges correspond to Swedish preschool, middle school and high school), such that if a new parental registration was identified during a given time period, exposure to parental EB was considered to be present (vs. absent) during that period.
