Cutoff Scores for MMPI-2 and MMPI-2-RF Cognitive-Somatic Validity Scales for Psychometrically Defined Malingering Groups in a Military Sample.

Abstract

This research examined cutoff scores for MMPI-2 and MMPI-2-RF validity scales specifically developed to assess non-credible reporting of cognitive and/or somatic symptoms. The validity scales examined included the Response Bias Scale (RBS), the Symptom Validity Scales (FBS, FBS-r), Infrequent Somatic Responses scale (Fs), and the Henry-Heilbronner Indexes (HHI, HHI-r). Cutoffs were developed by comparing a psychometrically defined non-malingering group with three psychometrically defined malingering groups (probable, probable to definite, and definite malingering) and a group that combined all malingering groups. The participants in this research were drawn from a military sample consisting largely of patients with traumatic brain injury (mostly mild traumatic brain injury). Specificities for cutoffs of at least 0.90 are provided. Sensitivities, predictive values, and likelihood ratios are also provided. RBS had the largest mean effect size (d) when the malingering groups were compared to the non-malingering group (d range=1.23-1.58).