Improving the Precision of the Glasgow Outcome Scale-Extended Using Item Response Theory: A TRACK-TBI Study. J Neurotrauma 2022 Jun;39(11-12):870-878
Date
03/24/2022Pubmed ID
35317604Pubmed Central ID
PMC9225413DOI
10.1089/neu.2021.0421Scopus ID
2-s2.0-85131693997 (requires institutional sign-in at Scopus site) 1 CitationAbstract
The Glasgow Outcome Scale-Extended (GOSE) is a functional outcome measure intended to place individuals with traumatic brain injury (TBI) into one of eight broad levels of injury-related disability. This simplicity is not always optimal, particularly when more granular assessment of individuals' injury recovery is desired. The GOSE, however, is customarily assessed using a multi-question interview that contains richer information than is reflected in the GOSE score. Using data from the multi-center Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) study (Nā=ā1544), we used item response theory (IRT) to evaluate whether rescoring the GOSE using IRT, which posits that a continuous latent variable (disability) underlies responses, can yield a more precise index of injury-related functional limitations. We fit IRT models to GOSE interview responses collected at three months post-injury. Each participant's level of functional limitation was estimated from the model (GOSE-IRT) and comparisons were made between IRT-based and standard (GOSE-Ordinal) scores. The IRT scoring resulted in 141 possible scores (vs. 7 GOSE-Ordinal scores in this sample of individuals with GOSE scores ranging between 2 and 8). Moreover, GOSE-IRT scores were significantly more strongly associated with measures of TBI-related symptoms, psychological symptoms, and quality of life. Our findings demonstrate that rescoring the GOSE interview using IRT yields more granular, meaningful measurement of injury-related functional limitations, while adding no additional respondent or examiner burden. This technique may have utility for many applications, such as clinical trials aiming to detect small treatment effects, and small-scale studies that need to maximize statistical efficiency.
Author List
Magnus BE, Balsis S, Giacino JT, McCrea MA, Temkin NR, Whyte J, Manley GT, Nelson LD, TRACK-TBI InvestigatorsAuthors
Michael McCrea PhD Professor in the Neurosurgery department at Medical College of WisconsinLindsay D. Nelson PhD Associate Professor in the Neurosurgery department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
Brain Injuries, TraumaticDisabled Persons
Glasgow Outcome Scale
Humans
Quality of Life