Measures in parents and their children were coded from the Semi-Structured Assessment for the Genetics of Alcoholism Interview (SSAGA)32. Age of initiation of regular drinking (Initiation) was the age at which participants reported first drinking regularly, defined as once a month for 6 months or more. Age of first intoxication (Intoxication) was the age at which participants first reported getting drunk, defined as slurred speech or being unsteady on one’s feet. Maximum drinks (MaxDrinks) was participants’ report of the largest number of drinks consumed in a 24-hour period. AUD lifetime criterion counts (AUDSx) were defined by the Diagnostic and Statistical Manual 5 (DSM-5)33. Those <23 years of age at their last assessment who did not endorse any AUD criteria were set to missing to ensure that participants had passed through the period of highest risk for onset of AUD before being classified as unaffected.
