Journal of the International Neuropsychological Society



Standard regression-based methods for measuring recovery after sport-related concussion


MICHAEL  McCREA  a1 a2 c1 , WILLIAM B.  BARR  a3 , KEVIN  GUSKIEWICZ  a4 a5 a6 , CHRISTOPHER  RANDOLPH  a7 , STEPHEN W.  MARSHALL  a6 a8 , ROBERT  CANTU  a4 a9 , JAMES A.  ONATE  a10 and JAMES P.  KELLY  a11
a1 Neuroscience Center, Waukesha Memorial Hospital, Waukesha
a2 Department of Neurology, Medical College of Wisconsin, Milwaukee
a3 Departments of Neurology and Psychiatry, New York University School of Medicine, New York
a4 Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill
a5 Department of Orthopedics, University of North Carolina at Chapel Hill, Chapel Hill
a6 Injury Prevention Research Center, University of North Carolina at Chapel Hill, Chapel Hill
a7 Department of Neurology, Loyola University Medical School, Maywood
a8 Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill
a9 Neurosurgery Service, Emerson Hospital, Concord
a10 Department of Rehabilitation Sciences, Athletic Training Program, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston
a11 Department of Neurosurgery, University of Colorado Health Sciences Center, Denver

Article author query
mccrea m   [PubMed][Google Scholar] 
barr wb   [PubMed][Google Scholar] 
guskiewicz k   [PubMed][Google Scholar] 
randolph c   [PubMed][Google Scholar] 
marshall sw   [PubMed][Google Scholar] 
cantu r   [PubMed][Google Scholar] 
onate ja   [PubMed][Google Scholar] 
kelly jp   [PubMed][Google Scholar] 

Abstract

Clinical decision making about an athlete's return to competition after concussion is hampered by a lack of systematic methods to measure recovery. We applied standard regression-based methods to statistically measure individual rates of impairment at several time points after concussion in college football players. Postconcussive symptoms, cognitive functioning, and balance were assessed in 94 players with concussion (based on American Academy of Neurology Criteria) and 56 noninjured controls during preseason baseline testing, and immediately, 3 hr, and 1, 2, 3, 5, and 7 days postinjury. Ninety-five percent of injured players exhibited acute concussion symptoms and impairment on cognitive or balance testing immediately after injury, which diminished to 4% who reported elevated symptoms on postinjury day 7. In addition, a small but clinically significant percentage of players who reported being symptom free by day 2 continued to be classified as impaired on the basis of objective balance and cognitive testing. These data suggest that neuropsychological testing may be of incremental utility to subjective symptom checklists in identifying the residual effects of sport-related concussion. The implementation of neuropsychological testing to detect subtle cognitive impairment is most useful once postconcussive symptoms have resolved. This management model is also supported by practical and other methodological considerations. (JINS, 2005, 11, 58–69.)

(Received April 12 2004)
(Revised July 29 2004)
(Accepted August 30 2004)


Key Words: Brain injury; Brain concussion; Athletic injuries.

Correspondence:
c1 Reprint requests to: Michael McCrea, Ph.D., ABPP-CN, Program Director, Neuroscience Center, Waukesha Memorial Hospital, 721 American Avenue, Suite 501, Waukesha, WI 53188. E-mail: michael.mccrea@phci.org