Effects of psychopathology and demographic characteristics on MMPI-2 scale scores

Using multiple linear regression analyses, we examined the effects of subject status for 6 demographic variables and the presence of psychopathology on variance in MMPI-2 scale scores. The analyses were designed to measure the incremental contribution of the demographic variables to scale variance beyond that explained by presence of psychopathology. Demographic variables were found to contribute little incremental variance for the validity and clinical scales, but did explain more than 10% of the score variance for 1 clinical scale, 2 content scales, and 5 supplemental scales. For these 8 scales, gender was most often the potent demographic variable and an expected influence. The results are discussed in light of the use of gender-based norms and in terms of other potential factors that might explain MMPI-2 scale score variance.