Utility of the MMPI-2-RF Validity Scales in Detection of Simulated Underreporting: Implications of Incorporating a Manipulation Check.

We examined the utility of the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) underreporting Validity Scales in a simulation design with a sample of 257 undergraduate college students. Extending past research by Sellbom and Bagby, we added a manipulation check to determine whether individuals complied with instructions to underreport and examined the impact of underreporting on all of the MMPI-2-RF substantive scales. Results indicated that individuals who complied with instructions to underreport produced statistically significantly and meaningfully higher scores on the MMPI-2-RF underreporting Validity Scales (Uncommon Virtues [L-r] and Adjustment Validity [K-r]) when compared with those who received standard instructions and with individuals who did not comply with instructions to underreport. Moreover, in comparisons with both groups, participants who complied with instructions to underreport had lower scores on the majority of the substantive scales. L-r and K-r added incremental predictive utility (in reference to one another) in differentiating individuals who underreported from individuals who were given standard instructions.