A-116 Neuropsychological Support for Use of Russell Posttraumatic Amnesia Classification of Traumatic Brain Injury

Abstract

Abstract Objective To compare neurocognitive outcomes between 3 traumatic brain injury (TBI) groups (mild, moderate, severe) across 3 TBI classification systems: Glasgow Coma Scale (GCS) and Russell (mild <1 hour, moderate <24 hours and severe >24 hours) and the modified (mild <24 hours, moderate < one week and severe > one week) posttraumatic amnesia (PTA) systems. Method Private practice archival data were reviewed for ambulance/hospital documentation of lowest GCS and PTA duration. Exclusion criteria included ESL and failed tests of engagement. Tests included WAIS, WMS, WRAT, Halstead Reitan etc. Results There were 91 patients (16 mild, 30 moderate and 45 severe); 45 were male. Mean age and education was 30.9 and 12.6. Russell PTA classification yielded significant differences (t-tests) between mild and moderate TBI on 8 of 46 tests/measures and 13 differences in moderate versus severe and 24 differences in mild versus severe TBI. Differences were always severe > moderate > mild impairment, with most in psychomotor speed, memory, working memory and executive/frontal functions consistent with TBI. The modified PTA classification yielded 2 significant differences between mild and moderate, 6 differences between moderate and severe and 22 differences between mild and severe TBI. GCS yielded 0 differences between mild and moderate, 7 differences between moderate and severe and 14 differences between mild and severe TBI. The modified PTA and GCS reduced moderate TBI numbers and some differences were opposite expectations. Conclusions Russell PTA was superior to the modified PTA system and GCS in separation/discrimination (without reversals) and maintenance of moderate TBI as a substantive category.