Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)




The MacAndrew Alcoholism Scale (MAC scale) has been found generally to differentiate alcoholics from control subjects. Some researchers have proposed it measures a general tendency to abuse drugs as well. The MAC scale's construct has been purported to tap unstable psychopathy at its high end and neuroticism at its low. The present study attempted to establish whether the MAC scale alone, the standard MMPI scales alone, or the MAC scale plus the standard MMPI scales and/or other MMPI research and Wiggins content scales provide the most effective differentiation of alcoholics and drug abusers from medical controls in a VA inpatient setting. The MAC scale was the single best predictor of group placement, although the highest rate of classification occurred when the MAC scale, 4/Pd, 1/Hs, and age were used together. The present study also contrasted alcoholics and drug abusers placed into groups on the basis of extreme MAC scale scores. It was hypothesized that substance abusers with low MAC scale scores (LMs) would exhibit neurotic MMPI profiles and the high MAC scale scorers (HMs) would present psychopathic profiles. This second set of hypotheses were partly supported. The HMs were significantly more impulsive, hostile, sensation-seeking, and angry. The LMs shared psychopathic features with the HMs and neurotic features with the medical controls. All three groups reported elevated levels of somatic complaints and dysphoria. The HMs and medical controls were similar on somatic preoccupation, unusual thinking, and religiosity. Two models were used to explain the findings. The first was Eysenck's three-way theoretical structure of personality which differentiated the three groups. The second was a two-way model which posits negatively correlated continua of psychopathy and neuroticism on which LMs and HMs are placed. The current data attest to the robustness of the MAC scale's construct in that established relations with MMPI variables using alcoholic subjects have been extended to drug abusers.