Use of the Personality Assessment Inventory (PAI) in individuals with traumatic brain injury

Primary objective: To evaluate the extent to which the Personality Assessment Inventory (PAI) is confounded by symptoms that are transdiagnostic between psychopathology and neurological sequelae. Methods: Sixty-one adults with moderate-to-severe traumatic brain injury (TBI) completed the PAI over the first year post-injury. Items that discriminated brain-injured individuals from a normative sample were identified using effect size analyses and were then subjected to principal components analysis (PCA) with varimax rotation. To explore whether the items identified in the PCA may be considered transdiagnostic in nature, an expert rating task and correlations with objective outcome measures were employed. Results: Effect sizes analyses identified 21 items that discriminated adults with TBI from the normative sample. Eight items associated with component 1 of the PCA were considered to be transdiagnostic. These items reflected health concerns and thinking problems from the Somatic Complaints, Depression and Schizophrenia scales. Items belonging to the other components reflected behaviours that are commonly associated with TBI, but not considered transdiagnostic. Conclusion: Using a comprehensive and multi-modal approach, results demonstrated good convergent validity for a small sub-set of items as being transdiagnostic. Overall, the findings support the PAI as a useful measure of psychiatric and emotional disturbances among persons with TBI.