Extensive AUDADIS-IV questions covered DSM-IV criteria for alcohol and drug-specific abuse and dependence for 10 classes of substances (sedatives, tranquilizers, painkillers, stimulants, cannabis, cocaine or crack, hallucinogens, Inhalants/solvents, Heroin, alcohol and nicotine). Substance use and age of substance use onset was determined by asking respondents about the age at which they first “smoked a first full cigarette” (nicotine use), “had at least 1 drink of any kind of alcohol (not counting small tastes or sips)” (alcohol use), used cannabis (cannabis use), or used cocaine or crack (cocaine use). Dependence on these substances was assessed separately via extensive items covering the DSM-IV criteria (American Psychiatric Association, 1994), which require 3 or more of 7 criteria within a 12-month period. Drug-specific dependence criteria were aggregated to yield diagnoses of drug dependence for each substance. The presence of symptoms for time periods whose duration was greater than 1 year, was assessed by asking the study participants the occurrence of those symptoms “on and off for a few months or longer”, “most days for at least a month,” or “within the same 1-year period”.
