Examining the Subacute Effects of Mild Traumatic Brain Injury with the CENTER-TBI Neuropsychological Test Battery.

This study investigates subacute cognitive effects of mild traumatic brain injury (MTBI)in the Trondheim Mild TBI Study, as measured, in part, by the neuropsychological test battery of the Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI), including computerized tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and traditional paper-and-pencil tests. We investigated whether cognitive function was associated with injury severity: intracranial traumatic lesions on neuroimaging, witnessed loss of consciousness (LOC), or posttraumatic amnesia (PTA) >1 hour. Further we explored which of the tests in the CENTER-TBI battery might be associated with the largest subacute effects of MTBI (i.e., at two weeks post injury). We recruited 177 patients with MTBI (16-59 years) from a regional trauma center and an outpatient clinic, 79 trauma control participants, and 81 community control participants. The MTBI group differed from community controls only on one traditional, test of processing speed (coding; p=0.009, Cliff's ∆=.20). Patients with intracranial abnormalities performed worse than those without on a traditional test (phonemic verbal fluency; p= 0.043, ∆=0.27), and patients with LOC performed differently on the Attention Switching Task from the CANTAB (p= 0.020, ∆=-0.20). Patients with PTA >1 hour performed worse than those with <1 hour on 10 measures, from traditional tests and the CANTAB (∆=0.33-0.20), likely attributable, at least in part, to pre-existing differences in intellectual functioning between groups. In general, those with MTBI had good neuropsychological outcome two weeks after injury and no particular CENTER-TBI computerized or traditional tests seemed to be more sensitive to subtle cognitive deficits.