Prediction of Return to Productivity After Severe Traumatic Brain Injury: Investigations of Optimal Neuropsychological Tests and Timing of Assessment
Abstract
Green RE, Colella B, Hebert DA, Bayley M, Kang HS, Till C, Monette G. Prediction of return to productivity after severe traumatic brain injury: investigations of optimal neuropsychological tests and timing of assessment.
Objectives
(1) To examine predictive validity of global neuropsychological performance, and performance on timed tests (controlling for manual motor function) and untimed tests, including attention, memory, executive function, on return to productivity at 1 year after traumatic brain injury (TBI). (2) To compare predictive validity at 8 weeks versus 5 months postinjury. (3) To examine predictive validity of early degree of recovery (8wk–5mo postinjury) for return to productivity.
Design
Longitudinal, within subjects.
Setting
Inpatient neurorehabilitation and community.
Participants
Patients (N=63) with moderate to severe TBI.
Interventions
Not applicable.
Main Outcome Measures
Primary outcome: return to productivity at 1 year postinjury. Primary predictors: neuropsychological composite scores. Control variables: posttraumatic amnesia, acute care length of stay (LOS), Glasgow Coma Scale score, age, and estimated premorbid intelligence quotient.
Results
Return to productivity was significantly correlated with global neuropsychological performance at 5 months postinjury (P<.05) and showed a trend toward significance at 8 weeks. Performance on the untimed composite score, and more specifically executive and memory functions, mirrored this pattern. Logical Memory performance significantly predicted return to productivity, but not other memory tests. Timed tests showed no significance or trend at either time point. Early degree of recovery did not predict return to productivity. Among control variables, only acute care LOS was predictive of return to productivity.
Conclusions
Findings validate utility of early neuropsychological assessment for predicting later return to productivity. They also provide more precise information regarding the optimal timing and test type: results support testing at 5 months postinjury on untimed tests (memory and executive function), but not simple attention or speed of mental processing. Findings are discussed with reference to previous literature.
aGraduate Department of Rehabilitation Sciences, University of Toronto, Toronto, ON, Canada
bToronto Rehabilitation Institute Toronto, Toronto, ON, Canada
cDepartment of Mathematics and Statistics, York University, Toronto, ON, Canada
dDepartment of Psychology, York University, Toronto, ON, Canada
Reprint requests to Robin Green, PhD, CPsych, Toronto Rehabilitation Institute, 550 University Ave, Toronto, ON, M5G 2A2, Canada
Supported by the Canadian Institutes of Health Research (grant nos. MOP-67072, MOP-86704).
No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit on the authors or on any organization with which the authors are associated.
ABSTRACT