The Utility of the MMPI-2-RF Validity Scales in Detecting Underreporting

This study examined the validity of the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF; Tellegen & Ben-Porath, 2011) Uncommon Virtues (L-r) and Adjustment Validity (K-r) scales in detecting underreporting. The study aimed to increment the previous literature in this field using a New Zealand population. We used a combined sample of 784 university students, with 173 participants completing the MMPI-2-RF with instruction to underreport in the context of applying for a job, and 611 completing the test under standard instructions. Results indicated that individuals who completed the MMPI-2-RF with underreporting instructions exhibited significantly lower scores on the majority of the MMPI-2-RF substantive scales, and significantly higher scores on the L-r and K-r validity scales. Additionally, L-r and K-r added incremental predictive utility over one another when differentiating the standard instruction and underreporting groups. Classification accuracy analyses provided additional evidence for the utility of the L-r and K-r scales by supporting their respective cut scores listed in the MMPI-2-RF manual (Ben-Porath & Tellegen, 2011). The findings of this study provide further evidence for the utility of the L-r and K-r scales in detecting underreporting extension to both a preemployment evaluation context and a novel population.