Length of post-traumatic amnesia and its prediction of neuropsychological outcome following severe to extremely severe traumatic brain injury in a litigating sample.

Primary Objective: The aim of the current study was to examine the relationship between duration of post-traumatic amnesia (PTA) and neuropsychological outcome at one or more years following severe to extremely severe traumatic brain injury (TBI) in a litigating sample.Research Design: Retrospective study design, using data collected from 2010 to 2017.Methods and Procedures: Data from 41 cases obtained from a private medicolegal neuropsychological database was examined. The database comprised information pertaining to TBI etiology, TBI severity parameters, demographic variables, neuropsychological test results and scores on psychological questionnaires. PTA duration was examined as a continuous variable. All cases that demonstrated non-credible effort were excluded.Main Outcomes and Results: Continuous PTA duration was not found to be a significant predictor of cognitive impairment across domains of verbal intellect, non-verbal intellect, working memory, information processing speed, immediate memory, delayed memory, and executive functioning.Conclusions: The predictive relationship between duration of PTA and cognitive impairment that has been reported in non-litigating populations did not exist in a litigating TBI sample. Findings illustrate the importance of investigating the relationships between injury variables and cognitive outcome in a population undergoing litigation, to provide better understanding of outcome in this subgroup of patients with TBI.