Cross-validation of the MMPI-2 in detecting malingered posttraumatic stress disorder

We attempted to cross-validate findings from a previous study (Elhai, Gold, Sellers, and Dorfman, in press) using a clinical sample of combat-related war veterans to distinguish genuine from malingered posttraumatic stress disorder (PTSD) on the MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, and Kaemmer, 1989). The MMPI-2 scores of 124 male combat war veterans at the PTSD outpatient treatment program of a Veterans Affairs Medical Center were compared with those of 84 adult college students instructed and trained to malinger PTSD. MMPI-2 overreporting variables examined were F, |F- Fb|, F-K, F(p), Ds₂, O-S, OT, and FBS. A stepwise discriminant analysis identified F, |F- Fb|, F-K, Ds₂, O-S, and OT as the best malingering predictors. A predictive discriminant analysis yielded good hit rates for the model with impressive cross-validation results. We assessed cutting scores for the predictors of the model. We discuss clinical implications for using the MMPI-2 to distinguish malingered PTSD from combat-related PTSD.