Resurrecting the ICAS: a competitor for the MAC in screening medical patients for alcoholism?

Although the MacAndrew scale (MAC) is the most widely used of the MMPI alcoholism screening scales, evidence to support its continued use is equivocal, and recent data raise serious questions about its efficacy in the screening of medical patients. In comparison, the Institutionalized Chronic Alcoholic Scale (ICAS), an 8-item scale, has an equivalent correct classification rate among male alcoholics and is significantly better than the MAC scale at identifying female alcoholics. Furthermore, misclassification rates among medical patients and normal persons are substantially lower for the ICAS than for the MAC scale, although the ICAS overidentifies potential alcoholism among normal women and female medical patients. However, reliability coefficients across the criterion and contrast samples are disappointingly low, and the use of the ICAS cannot be defended on that basis.