Predicting co-morbid traumatic brain injury and psychosis from neuropsychological profile

The relationship between traumatic brain injury (TBI) and psychosis, and the phenomenology of psychosis following traumatic brain injury (PFTBI), is poorly understood (see Batty et al., 2013 for review). Impaired neurocognition has long been empirically established following TBI and in patients with psychosis (DeLisi, 2001, Henik and Salo, 2004 and Mathias and Weaton, 2007), suggesting that dually-diagnosed PFTBI patients are susceptible to substantial neurocognitive deficits. Moreover, while there appears to be some overlap in the neurocognitive deficits associated with TBI and schizophrenia patient groups, they appear distinct in profile, providing impetus for elucidating PFTBI-specific deficits. We have shown that neuropsychological reports taken from case study and/or patient chart information appear to underrepresent PFTBI impairment (Batty et al., 2015a, Batty et al., 2015b and Batty et al., 2016). In a novel study we administered the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS: Randolph, 1998) to PFTBI patients, and demonstrated extensive neurocognitive deficits relative to both normative scores and three cohorts of controls: TBI, schizophrenia, and non-clinical (Batty et al., 2016). Importantly, these findings better reflect established neuropsychological deficits in the separate TBI and schizophrenia literatures. Here we aimed to determine whether dual-diagnosis can be predicted by neuropsychological profile, as distinct from TBI, schizophrenia, and non-clinical controls