Michigan Assessment- Screening Test for Alcohol and Drugs (MAST=AD): Evaluation in a Clinical Sample Joseph Westermeyer, M.D., M.P.H., Ph.D., Ilhan Yargic, M.D., Paul Thuras, Ph.D. In this study, we sought to evaluate a modification of the Michigan Alcohol Screening Test designed to include problems associated with other drug abuse=dependence besides alcohol. Scores of the lifetime Michigan Assess- ment-Screening Test=Alcohol-Drug (MAST=AD) were compared to other lifetime measures of substance abuse and dependence and to psychiatric scales reflecting current or recent symptoms. Two university medical centers with alco- hol-drug programs located within departments of psychiatry hosted 520 pa- tients with alcohol-drug-related diagnoses. Patients completed their own MAST=AD using a paper-and-pencil format. Based on interviews with the patient, a research associate rated the patients’ substance-related problems on the Minnesota Substance Abuse Problem Scale (M-SAPS) and obtained information on lifetime treatment for substance abuse. An addictions psy- chiatrist determined abuse or dependence and made a current diagnosis of alco- hol abuse=dependence only, drug abuse=dependence only, and alcohol plus drug abuse=dependence. The MAST=AD was highly correlated with the M-SAPS and several other measures of substance abuse morbidity. Patients with alco- hol-only and drug-only diagnoses did not differ from one another on the MAST=AD, although both groups had lower scores than those with alcohol plus drug diagnoses. Current psychosocial morbidity as assessed by the patient and the psychiatrist was associated with the MAST=AD, although less strongly than with lifetime substance abuse measures. The lifetime MAST=AD demonstrates reliability as a severity measure for alcohol and=or or drug abuse. With minor modification, this standard measure can be Received March 15, 2002; revised June 3, 2002; accepted July 18, 2002. From the Department of Psychiatry, Minneapolis VA Medical Center, Minneapolis, Minn. (Drs. Westermeyer, Yargic and Thuras) and the Department of Psychiatry, University of Minnesota, Minneapolis, Minn. (Drs. Westermeyer and Thuras). Dr. Yargic is now at the Department of Psychiatry, University of Istanbul, Istanbul, Turkey. Address correspondence to Dr. Westermeyer, Department of Psychiatry, VAMC, 1 Veterans Drive, Minneapolis, MN 55417. E-mail: weste010@umn.edu. The American Journal on Addictions, 13:151–162, 2004 Copyright # American Academy of Addiction Psychiatry ISSN: 1055-0496 print / 1521-0391 online DOI: 10.1080=10550490490435948 151