The Use of Special MMPI Scales for Prediction of Response to Chemical Dependency Treatment

The purpose of this study was to investigate how selected special scales of the Minnesota Multiphasic Personality Inventory (MMPI) are related to treatment completion and treatment outcome in a privately operated chemical dependency treatment program. Multiple regression analyses, discriminant function analyses, and canonical correlation were used to analyze the data.In Part I of this study the MMPI scales of Lie, K, Conscious Anxiety, Conscious Repression, Dependency, Dominance, Control, Admission, and Denial were examined to determine their ability to predict treatment completion for 182 males and 48 females. Completion of treatment was associated with lower scores on the Conscious Repression scale and higher scores on the Control scale. Male completers also had higher Dependency scores, while female completers tended to score lower on the Dependency scale than those who did not complete treatment. However, the selected scales seem to be of limited value in predicting treatment completion because they accounted for a relatively small proportion of the variance.Part II of this study examined treatment outcome in groups of patients at 1, 6, or 12 months following completion of treatment. Self- reports of chemical use, informant reports of chemical use, employment status and the number of admissions to a detoxification facility were used as measures of post treatment adjustment. Improvement was most consistently associated with lower scores on the Admission and Hypomania scales of the MMPI and more frequent attendance at Alcoholics Anonymous meetings.