Comparison of MMPI-2 and PAI validity indicators to detect feigned depression and PTSD symptom reporting.

The purpose of this study was to compare the clinical utility of PAI and MMPI-2 validity indicators to detect exaggeration of psychological symptoms. Participants were 49 (75.5% female) Australian university students who completed the MMPI-2 and PAI under one of three conditions: Control [i.e., honest responding (n=20)], Feign Post Traumatic Stress Disorder [PTSD (n=15)], or Feign Depression (n=14). Participants instructed to feign depression or feign PTSD had significantly higher scores on the majority of MMPI-2 and PAI validity indicators compared with controls. The Meyers Validity Index, the Obvious-Subtle index, and the Response Bias Scale were the most accurate MMPI-2 validity indicators. Diagnostic-specific MMPI-2 validity indicators, such as the Infrequency-PSTD scales and Malingered Depression scale, were not effective at detecting participants instructed to feign those conditions. For the PAI, the most accurate validity indicator was the MAL index; however, the detection rate using this validity indicator was modest at best. The MMPI-2 validity indicators were clearly superior to those on the PAI at identifying feigned versus honest responding in this sample.