Abstract
The range and utility of the MMPI-derived MacAndrew Alcoholism Scale (MAC) and the Heroin Addiction Scale (He) was assessed with a large sample of drug addicts with and without concurrent alcoholism. Results indicated that addicts with a co-existing alcohol problem obtained higher MAC scores than addicts without a current alcohol problem. Opiate abusers scored higher on the MAC than non-opiate abusers. No such effects were observed with the He scale. The MAC is a particularly robust scale that taps generic substance abuse and may even be sensitive enough to detect alcoholism in drug addicts.