The neuropsychological impact of sports-related concussion: A meta-analysis
There is increasing interest in the potential neuropsychological impact of sports-related concussion. A meta-analysis of the relevant literature was conducted to determine the impact of sports-related concussion across six cognitive domains. The analysis was based on 21 studies involving 790 cases of concussion and 2014 control cases. The overall effect of concussion (d = 0.49) was comparable to the effect found in the non-sports-related mild traumatic brain injury population (d = 0.54; Belanger et al., 2005). Using sports-concussed participants with a history of prior head injury appears to inflate the effect sizes associated with the current sports-related concussion. Acute effects (within 24 hr of injury) of concussion were greatest for delayed memory, memory acquisition, and global cognitive functioning (d = 1.00, 1.03, and 1.42, respectively). However, no residual neuropsychological impairments were found when testing was completed beyond 7 days postinjury. These findings were moderated by cognitive domain and comparison group (control group versus preconcussion self-control). Specifically, delayed memory in studies utilizing a control group remained problematic at 7 days. The implications and limitations of these findings are discussed. (JINS, 2005, 11, 345–357.)(Received December 23 2004)
(Revised January 19 2005)
(Accepted January 19 2005)
Key Words: Brain concussion; Head injury; Mild concussion; Sequelae; Traumatic brain injury; Football; Soccer.
c1 Reprint requests to: Heather Belanger, Ph.D., James A. Haley Veterans' Hospital, Physical Medicine and Rehabilitation—117, 13000 Bruce B. Downs Blvd., Tampa, FL 33612. E-mail: Heather.Belanger@med.va.gov