The objective of this study was to compare the Validity-10 scale with the PAI Negative Impression Management Scale (PAI-NIM) for detecting exaggerated symptom reporting in active-duty military service members (SMs) admitted with unremitting mild TBI symptoms and comorbid psychological health conditions (mTBI/PH). Data were analyzed from 254 SMs who completed the Neurobehavioral Symptom Inventory (NSI) and Personality Assessment Inventory (PAI) as a part of a larger battery of self-report symptom scales upon admission to the intensive-outpatient TBI treatment program at a military medical center. Symptom exaggeration was operationalized using the PAI Negative Impression Management Scale (PAI-NIM). A PAI-NIM score of ≥73 was categorized as positive for symptom exaggeration (SVTpos), while a lower score was categorized as negative for symptom exaggeration (SVTneg). SMs in the SVTpos group (n = 34) had significantly higher scores (p ≤ .004) on the PAI clinical scales as well as on the NSI total score (range: d = 0.59-1.91) compared to those who were SVTneg (n = 220). The optimal cut-score for the NSI Val-10 scale to identify possible symptom exaggeration was ≥26 (sensitivity = .29, specificity = .95, PPP = .74, NPP = .71). In patients suffering from mTBI/PH, the Validity-10 requires a higher cut-score than previously reported to be useful as a metric of exaggerated symptom reporting.
Keywords: Mild traumatic brain injury; Validity-10; neurobehavioral symptom inventory; post-concussive symptoms.