the week during the period data were collected in each ED facility. Across all studies, patient samples of those 18 and older were selected from ED admission forms, which included walk-in patients as well as those arriving by ambulance, and reflected consecutive arrival at the ED. The particular sampling frame in a study depended on the number of patients admitted to the ED facility covered in each study. Once selected for the study, and as soon as possible after ED admission, patients were approached with an informed consent to participate, and were then breathalyzed and administered a questionnaire of about 25 minutes in length by trained interviewers while the patient was in the waiting room or treatment area and/or following treatment. Patients who were too severely injured or ill to be interviewed in the ED and who were subsequently hospitalized were interviewed later after their condition had stabilized. Both injured and non-injured patients were interviewed regarding quantity and frequency of usual drinking and frequency of high maximum occasions during the last year, frequency of drunkenness, alcohol dependence and abuse questions, and demographic characteristics.
