Relationship between the Glasgow Outcome Scale Extended and Measures of Disability, Function, Participation, Psychosocial Symptoms & Life Satisfaction Following Moderate-Severe Traumatic Brain Injury

Research Objectives: First, to determine the relationship between the Glasgow Outcome Scale Extended (GOSE) and other measures of global function (Functional Independence Measure [FIM], Disability Rating Scale [DRS]) post traumatic brain injury (TBI). Second, to determine the relationship between GOSE and participation (Participation Assessment of Recombined Tools Objective [PARTO]), psychosocial (Patient Health Questionnaire-9 [PHQ9], Generalized Anxiety Disorder-7 [GAD7]), and life satisfaction (Satisfaction with Life Scale [SWLS]) outcomes post-TBI.

Design: Retrospective analysis of prospectively collected cross-sectional data.

Setting: TBI Model Systems (TBIMS) centers.

Participants: Adults one-year post moderate-severe TBI who completed the GOSE and at least one additional outcome measure.

Interventions: None.

Main Outcome Measures: GOSE, FIM, DRS, PARTO, SWLS, PHQ9, GAD7.

Results: Of 19,245 TBIMS participants, we included 10,465 (median [IQR] age=42 [26,59] years, 73% male). For each stepwise increase in GOSE score, there was a statistically significant increase in median DRS and FIM scores (p <.008). Between GOSE scores 3-4, 4-5 and 5-6, there were no differences in PHQ9 and GAD7 medians (p>.01). Between GOSE scores 3-4 and 4-5, there were no differences in SWLS medians (p>.01). For GOSE scores 2-7, PARTO scores were lower than the previously published clinical threshold (1.95) and between GOSE scores 7-8 there was no difference in median PARTO scores (p=.176). Within each GOSE score, there were wide distributions in DRS, FIM, PARTO, PHQ9, GAD7, and SWLS scores (e.g., FIM range 18-126 for GOSE=3 and SWLS range 5-35 for GOSE=8). All statistical tests remained significant after Bonferroni correction for multiple comparisons.

Conclusions: Although increasing GOSE scores were associated with better DRS and FIM scores, there was substantial variability in these measures within each GOSE category suggesting global function is assessed differently across measures. On domain-specific measures, multiple GOSE scores were associated with similar levels of participation, depression, anxiety, and life satisfaction. Over reliance on a single measure of global function disregards critical information about functional, participation, psychosocial, and life satisfaction outcomes post-TBI.

Author(s) Disclosures: None.