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Factors moderating neuropsychological outcomes following mild traumatic brain injury: A meta-analysis

Published online by Cambridge University Press:  04 May 2005

HEATHER G. BELANGER
Affiliation:
James A. Haley Veterans' Hospital, Tampa, Florida University of South Florida Department of Psychology, Tampa, Florida Defense and Veterans Brain Injury Center, Tampa, Florida Henry M. Jackson Foundation, Rockville, Maryland
GLENN CURTISS
Affiliation:
James A. Haley Veterans' Hospital, Tampa, Florida University of South Florida Department of Psychiatry, Tampa, Florida Defense and Veterans Brain Injury Center, Tampa, Florida
JASON A. DEMERY
Affiliation:
James A. Haley Veterans' Hospital, Tampa, Florida University of Florida, Department of Clinical and Health Psychology, Gainesville, Florida
BRIAN K. LEBOWITZ
Affiliation:
James A. Haley Veterans' Hospital, Tampa, Florida University of Cincinnati, Department of Psychology, Cincinnati, Ohio
RODNEY D. VANDERPLOEG
Affiliation:
James A. Haley Veterans' Hospital, Tampa, Florida University of South Florida Department of Psychology, Tampa, Florida University of South Florida Department of Psychiatry, Tampa, Florida Defense and Veterans Brain Injury Center, Tampa, Florida

Abstract

There continues to be debate about the long-term neuropsychological impact of mild traumatic brain injury (MTBI). A meta-analysis of the relevant literature was conducted to determine the impact of MTBI across nine cognitive domains. The analysis was based on 39 studies involving 1463 cases of MTBI and 1191 control cases. The overall effect of MTBI on neuropsychological functioning was moderate (d = .54). However, findings were moderated by cognitive domain, time since injury, patient characteristics, and sampling methods. Acute effects (less than 3 months postinjury) of MTBI were greatest for delayed memory and fluency (d = 1.03 and .89, respectively). In unselected or prospective samples, the overall analysis revealed no residual neuropsychological impairment by 3 months postinjury (d = .04). In contrast, clinic-based samples and samples including participants in litigation were associated with greater cognitive sequelae of MTBI (d = .74 and .78, respectively at 3 months or greater). Indeed, litigation was associated with stable or worsening of cognitive functioning over time. The implications and limitations of these findings are discussed. (JINS, 2005, 11, 215–227.)

Type
Research Article
Copyright
© 2005 The International Neuropsychological Society

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