Inconsistent Responding in a Criminal Forensic Setting: An Evaluation of the VRIN-r and TRIN-r Scales of the MMPI-2-RF

Criminal forensic evaluations are complicated by the risk that examinees will respond in an unreliable manner. Unreliable responding could occur due to lack of personal investment in the evaluation, severe mental illness, and low cognitive abilities. In this study, 31% of Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF; Ben-Porath & Tellegen, 2008/2011) profiles were invalid due to random or fixed-responding (T score ≥ 80 on the VRIN-r or TRIN-r scales) in a sample of pretrial criminal defendants evaluated in the context of treatment for competency restoration. Hierarchical regression models showed that symptom exaggeration variables, as measured by inconsistently reported psychiatric symptoms, contributed over and above education and intellectual functioning in their prediction of both random responding and fixed responding. Psychopathology variables, as measured by mood disturbance, better predicted fixed responding after controlling for estimates of cognitive abilities, but did not improve the prediction for random responding. These findings suggest that random responding and fixed responding are not only affected by education and intellectual functioning, but also by intentional exaggeration and aspects of psychopathology. Measures of intellectual functioning and effort and response style should be considered for administration in conjunction with self-report personality measures to rule out rival hypotheses of invalid profiles.

Personality Assessment Inventory profiles of veterans: Differential effects of mild traumatic brain injury and psychopathology

OBJECTIVE

Neuropsychiatric complaints often accompany mild traumatic brain injury (mTBI), a common condition in post-deployed Veterans. Self-report, multi-scale personality inventories may elucidate the pattern of psychiatric distress in this cohort. This study investigated valid Personality Assessment Inventory (PAI) profiles in post-deployed Veterans.

METHOD

Measures of psychopathology and mTBI were examined in a sample of 144 post-deployed Veterans divided into groups: healthy controls (n = 40), mTBI only (n = 31), any mental health diagnosis only (MH; n = 25), comorbid mTBI and Posttraumatic Stress Disorder (mTBI/PTSD; n = 23), and comorbid mTBI, PTSD, and other psychological diagnoses (mTBI/PTSD/MDD+; n = 25).

RESULTS

There were no significant differences between the mTBI and the control group on mean PAI subscale elevation, or number of subscale elevations above 60T or 70T. The other three groups had significantly higher overall mean scores, and more elevations above 60 and 70T compared to both controls and mTBI only. The mTBI/PTSD/MDD+ group showed the highest and most elevations. After entering demographics, PTSD, and number of other psychological diagnoses into hierarchical regressions using the entire sample, mTBI history did not predict mean PAI subscale score or number of elevations above 60T or 70T. PTSD was the only significant predictor. There were no interaction effects between mTBI and presence of PTSD, or between mTBI and total number of diagnoses.

CONCLUSIONS

This study suggests that mTBI alone is not uniquely related to psychiatric distress in Veterans, but that PTSD accounts for self-reported symptom distress.