The Neurological Outcome Scale for Traumatic Brain Injury (NOS-TBI): II. Reliability and Convergent Validity

Abstract

A standardized measure of neurological dysfunction specifically designed for TBI currently does not exist and the lack of assessment of this domain represents a substantial gap. To address this, the Neurological Outcome Scale for Traumatic Brain Injury (NOS-TBI) was developed for TBI outcomes research through the addition to and modification of items specifically relevant to patients with TBI, based on the National Institutes of Health Stroke Scale. In a sample of 50 participants (mean age ¼ 33.3 years, SD ¼ 12.9) 18 months (mean ¼ 3.1, SD ¼ 3.2) following moderate (n ¼ 8) to severe (n ¼ 42) TBI, internal consistency of the NOS-TBI was high (Cronbach's alpha ¼ 0.942). Test-retest reliability also was high (r ¼ 0.97, p < 0.0001), and individual item kappas between independent raters were excellent, ranging from 0.83 to 1.0. Overall inter-rater agreement between independent raters (Kendall's coefficient of concordance) for the NOS-TBI total score was excellent (W ¼ 0.995). Convergent validity was demonstrated through significant Spearman rank-order correlations between the NOS-TBI and the concurrently administered Disability Rating Scale (r ¼ 0.75, p < 0.0001), Rancho Los Amigos Scale (r ¼ À0.60, p < 0.0001), Supervision Rating Scale (r ¼ 0.59, p < 0.0001), and the FIM Ô (r ¼ À0.68, p < 0.0001). These results suggest that the NOS-TBI is a reliable and valid measure of neurological functioning in patients with moderate to severe TBI.

Neurological Outcome Scale for Traumatic Brain Injury: III. Criterion-Related Validity and Sensitivity to Change in the NABIS Hypothermia-II Clinical Trial

“…The modified Marshall CT classification was also a significant predictor of NRS-R performance at 6 months. Lesion volume prediction (in cm 3 ) was significant for NRS-R performance at 3 months postinjury ( p = 0.0043), but was nonsignificant for all other measures at all other endpoints.…”

“…Lesion volume was also included in this study as a separate variable, which was defined as the sum of the volumes of epi-and subdural hematomas, and intraparenchymal hemorrhages in cm 3 , as determined from initial or preoperative CT scans as measured by a neuroradiologist. Finally, the GCS score at trauma triage was used.…”

“…Inclusion criteria included age 16-45 years, nonpenetrating brain injury, and failure to obey simple commands (i.e., Glasgow Coma Scale [GCS] 8 score of [3][4][5][6][7][8]. Exclusions included GCS score of 3 with nonreactive pupils, GCS score of 7-8 with normal brain computed tomography (CT) scan, inability to measure an accurate GCS score, Abbreviated Injury Severity score of 4 or greater for organs other than the brain, systolic blood pressure less than 110 mmHg, diastolic blood pressure less than 60 mmHg, persistent hypoxia (O 2 saturation < 94%), or a positive pregnancy test.…”

“…a This is the Bigler version of the Marshall CT classification scheme. b Lesion volume is the sum of the volume of epidural and subdural hematomas, and intraparenchymal hemorrhages in cm 3 as measured on the initial CT scan.…”

“…Details of the development and psychometric properties of the NOS-TBI have been presented previously. [3][4][5] Test items include assessment of motor and sensory functions, visual fields, facial paresis, and limb ataxia to assess gross neurological functioning in addition to items with specific applicability to patients with TBI, such as pupillary response, olfaction, and gait ataxia. The NOS-TBI was included as a recommended measure in the National Institute of Neurological Disorders and Stroke (NINDS) and Federal Interagency Common Data Elements (CDE) Initiative for TBI 6 and is currently a supplemental measure in version 2.0 of these recommendations (http://www.commondataelements.ninds.nih.gov), which has merged recommended measures for adults 6 and children 7 with TBI.…”