Citation

Schmidt JD, Register-Mihalik JK, Mihalik JP, Kerr ZY, Guskiewicz KM. Med. Sci. Sports Exerc. 2012; 44(9): 1621-1628.

Affiliation

1The University of North Carolina at Chapel Hill.

Copyright

(Copyright © 2012, Lippincott Williams and Wilkins)

DOI

10.1249/MSS.0b013e318258a9fb

PMID

22525765

Abstract

PURPOSE:: To determine if agreement exists between baseline comparison (comparison of post-concussion scores to individualized baseline scores) and normative comparison (comparison of post-concussion scores to a normative mean) in identifying acute impairments following concussion. METHODS:: 1,060 collegiate student-athletes completed baseline testing as part of an ongoing clinical program. Gender-specific normative means were obtained from a subset of 673 athletes with no history of self-reported concussion, learning disabilities, or attention deficit disorders. Concussions were later diagnosed in 258 athletes who had completed baseline testing. The athletes completed their first assessment within 10-days following injury. Athletes completed a computerized neurocognitive test (Automated Neuropsychological Assessment Metrics), postural control assessment (Sensory Organization Test), and a 15-item graded symptom checklist at baseline and again following injury. We computed two post-concussion difference scores for each outcome measure: (1) Baseline comparison = post-concussion score - individualized baseline score; and (2) Normative comparison = post-concussion score - normative mean. Athletes were considered impaired if post-concussion difference exceeded the reliable change parameters. McNemar tests were used to assess agreement on impairment status (impaired, unimpaired) between comparison methods for each outcome measure. RESULTS:: The baseline comparison method identified 2.6 times more impairments than the normative comparison method for Simple Reaction Time- Test 1 (p=0.043). The normative comparison method identified 7.6 times more impairments than the baseline comparison method for Mathematic Processing (p<0.001). No other disagreements were observed for postural control or symptom severity. CONCLUSIONS:: Our findings suggest that, when using these concussion assessment tools, clinicians may consider using normative data in lieu of individualized baseline measures. This may be especially useful to clinicians with limited resources and an inability to capture baselines on all athletes.

Language: en