The Miller Forensic Assessment of Symptoms Test (M-FAST) in Veterans

Objective: To evaluate the convergent validity and diagnostic accuracy of the Miller Forensic Assessment of Symptoms Test (M-FAST) in a Veteran sample. Method: Participants were identified and recruited for a study of neurocognition of traumatic brain injury (TBI) and posttraumatic stress disorder in post 9/11 Veterans. A standardized neuropsychological battery was administered. From the parent study sample, 405 completed both the M-FAST and the Personality Assessment Inventory (PAI). Nonparametric tests were used to compare the M-FAST Total score across diagnostic and disability variable groupings. Correlations were calculated for the M-FAST Total score in comparison to the PAI symptom validity indices and clinical scales. Diagnostic accuracy analyses were employed to assess M-FAST Total score cutoffs to identify a noncredible group per PAI overreporting scales. Results: The M-FAST Total score was not significantly higher for individuals with a TBI history, but was higher in those with major depressive disorder, posttraumatic stress disorder, and receiving Veterans Affairs disability. The M-FAST correlated well to established symptom validity scales in the PAI, with smaller effects seen when correlated to PAI clinical scales. Using a cutoff of ≥5, the M-FAST achieved an area under the curve of .754 but resulted in a very poor sensitivity of 24. Conclusions: This study evaluated the M-FAST as a screening or adjunct measure of symptom validity in postdeployed Veterans. Even after reducing the Total score cutoff from the manual recommended score, sensitivity remained poor; thus, the M-FAST should not be used as a sole symptom validity tests outside of screening contexts. Public Significance Statement This study provides evidence supporting the use of the Miller Forensic Assessment of Symptoms Test (M-FAST) as a measure of symptom validity in the Veteran population when compared with the embedded validity measures on the PAI (Negative Impression Management and Malingering Index). Using a cutoff of ≥5, the M-FAST achieved adequate specificity and AUC, though sensitivity was low. The M-FAST may be more sensitive to psychiatric symptoms than more general neurocognitive complaints.