Comparison of Four MMPI-2 Validity Scales in Identifying Invalid Neurocognitive Dysfunction in Traumatic Brain Injury Litigants

Four Minnesota Multiphasic Personality Inventory-2 (MMPI-2) validity scales, the F Scale, Symptom Validity Scale (FBS), Henry-Heilbronner Index (HHI), and Response Bias Scale (RBS), were evaluated in 60 personal injury litigants who sustained a traumatic brain injury (TBI). Based on a modified Slick, Sherman, and Iverson ( 1999 ) diagnostic criteria for malingered neurocognitive dysfunction and utilizing test-effort measures embedded in standard neuropsychological testing, a group of 23 patients with probable invalid neurocognitive dysfunction (PI) and a comparable group of 37 patients with noninvalid neurocognitive dysfunction were identified and compared with respect to their MMPI-2 validity scale scores. Logistic regression analyses, receiver-operating characteristic curve and area under the curve analyses, as well as sensitivity, specificity, positive predictive value, and negative predictive value analyses all revealed that RBS performed better than F, FBS, and HHI in classifying PIs. The present results add to a number of recent studies that suggest that RBS is a useful predictor of symptom validity failure and probable neuropsychological malingering among litigating TBI patients. The study also encourages further research employing embedded test-effort measures in classifying invalid neurocognitive dysfunction per the Slick et al. diagnostic criteria.