Related Experiment Video
Updated: Dec 31, 2025
11:32
A Neuroscientific Approach to the Examination of Concussions in Student-Athletes
Published on: December 8, 2014
13.1K
Using Variance to Explore the Diagnostic Utility of Baseline Concussion Testing.
Alexander D Rebchuk1,2, Harrison J Brown2, Michael S Koehle2,3
1Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
Journal of Neurotrauma
|January 14, 2020
Summary
Baseline concussion testing using Graded Symptom Checklist (GSC), Standardized Assessment of Concussion (SAC), and Balance Error Scoring System (BESS) offers limited benefit. However, baseline King-Devick Test (KDT) data is valuable due to high player variability.
Area of Science:
- Sports Medicine
- Neurology
- Clinical Assessment
Background:
- Concussion assessment relies on tools like the Graded Symptom Checklist (GSC), Standardized Assessment of Concussion (SAC), Balance Error Scoring System (BESS), and King-Devick Test (KDT).
- The utility of baseline testing for these concussion assessment tools remains uncertain.
- Understanding test variability is crucial for accurate concussion diagnosis in athletes.
Purpose of the Study:
- To investigate within-subject and between-subjects variability of GSC, SAC, BESS, and KDT over repeated assessments in collegiate football players.
- To determine if baseline testing improves the diagnostic utility of these concussion assessment tools by reducing performance variability.
- To examine practice effects associated with repeated concussion testing during a season.
Main Methods:
- Observational cohort study involving 35 male collegiate football players over two seasons.
- Weekly clinical concussion assessments using GSC, SAC, BESS, and KDT.
- Bootstrap analysis to compare within-subject and between-subjects variability; mixed-model analyses for practice effects.
Main Results:
- For GSC and BESS, within-subject and between-subjects variability did not significantly differ.
- King-Devick Test (KDT) showed significantly higher between-subjects variability (79.8%) than within-subject variability (20.2%).
- Standardized Assessment of Concussion (SAC) exhibited significantly greater within-subject variance (66.8%) than between-subjects variance (33.8%).
- A small, significant practice effect was noted for BESS and KDT.
Conclusions:
- For GSC, SAC, and BESS, comparing in-season scores to baseline is not more beneficial than using normative data for identifying concussion-related neurological changes.
- Baseline King-Devick Test (KDT) comparison is beneficial due to its significantly higher between-subjects variability, aiding in concussion detection.
- Repeated testing may introduce practice effects, particularly for BESS and KDT.
