PSYCHOMETRIC PROPERTIES OF MMPI FACTOR SCALES

The psychometric properties of nine factor scales (Costa, Zonderman, Williams & McCrae, 1985; Journal of Personality and Social Psychology 48, 925-933) of the Minnesota Multiphasic Personality Inventory (MMPI) developed for nonclinical populations were examined over a one year test-retest interval. In the initial testing session, 40 university undergraduate roommate pairs (i.e. 80 subjects) were administered a microcomputerized version of the MMPI; 55 of these subjects were retested one year later. Reliability information indicated that only some of the factor scales were both internally consistent and temporally stable. Roommate ratings on the underlying dimensions were used as criteria, and analyses indicated that not all the MMPI factor scales possessed adequate criterion validity. Overall, these results indicate both psychometric strengths and shortcomings for the scales derived by Costa et al. (1985) in their item factor analysis of the MMPI. © 1991.