Examination of the MMPI-3 over-reporting scales in a forensic disability sample

Objective: The aim of this investigation was to provide information about the utility of the newly revised and renormed Minnesota Multiphasic Personality Inventory-3 (MMPI-3) over-reporting scales in a forensic disability sample. Method: Participants consisted of 550 non-head injury disability-related referrals (i.e. 95.6% for worker's compensation) and were primarily diagnosed with an adjustment disorder, depressive disorder, or posttraumatic stress disorder. Criterion measures included performance validity indicators and non-MMPI symptom validity indicators. Results: Correlation analyses showed that validity scale F was most strongly associated with non-MMPI symptom validity indicators, whereas F, Fs, FBS, and RBS were comparable to each other in their associations with performance validity indicators. Group mean comparisons between Pass versus Fail PVT groups showed that RBS consistently yielded the largest effect sizes. Using established structured criteria for Malingered Neurocognitive Dysfunction (MND), additional group mean comparisons showed that RBS, followed by Fs, F, and FBS, performed well in differentiating genuine responders from MND examinees. Classification accuracy estimates indicated that the MMPI-3 over-reporting scales performed well in the prediction of Probable/Definite MND and, as expected, to a lesser degree of Possible MND. Conclusions: Practical applications, study limitations, and directions for future research are discussed. The overall findings from this study provide empirical support for the utility of the MMPI-3 over-reporting scales in detecting negative response bias in forensic disability evaluations.