Elevation differences between MMPI-2 clinical and Restructured Clinical (RC) scales: Frequency, origins, and interpretative implications

The frequency, origin, and interpretative implications of elevation differences on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) clinical and restructured clinical (RC) scales were examined. Two large clinical samples consisting of 1,770 outpatients and 2,438 inpatients were used for this study. Three potential factors (Demoralization, subtle items, and K correction) were explored as to the extent to which they contributed to elevation differences between a clinical scale and its restructured counterpart. Results showed that differences in elevation between clinical and RC scales occurred between 10% and 35% of cases. Demoralization, subtle items, and K correction contributed substantially to elevation differences. Findings indicate that core descriptors of a clinical scale should be emphasized only when its corresponding RC scale is also elevated, whereas for Scales 4, 6, and 8, elevated scores on the RC scales are interpretable even when the corresponding clinical scales are not elevated.