RT Journal
A1 Matser ET, Kessels AG, Lezak MD, Jordan BD, Troost J
T1 NEuropsychological impairment in amateur soccer players
JF JAMA
JO JAMA
YR 1999
FD September 8
VO 282
IS 10
SP 971
OP 973
DO 10.1001/jama.282.10.971
UL http://dx.doi.org/10.1001/jama.282.10.971
AB Context 
                  Soccer players incur concussions during matches and training sessions,
as well as numerous subconcussive blows to the head from impacts with the
soccer ball (headers). The combination of soccer-related
concussions and the number of headers may be a risk for chronic traumatic
brain injury (CTBI).Objective 
                  To determine whether amateur soccer players have evidence of CTBI.Design, Setting, and Participants 
                  Cross-sectional study of 33 amateur soccer players and 27 amateur athletes
involved in swimming and track (controls) in the Netherlands who underwent
interviews and neuropsychological testing.Main Outcome Measures 
                  Performance of soccer players vs controls on 16 neuropsychological tests
having 27 outcomes.Results 
                  Compared with control athletes, amateur soccer players exhibited impaired
performance on tests of planning (39% vs 13%; P=.001)
and memory (27% vs 7%; P=.004). Among soccer players,
9 (27%) had incurred 1 soccer-related concussion and 7 (23%) had had 2 to
5 concussions during their career. The number of concussions incurred in soccer
was inversely related to the neuropsychological performance on 6 of the neuropsychological
tests.Conclusions 
                  Our results indicate that participation in amateur soccer in general
and concussion specifically is associated with impaired performance in memory
and planning functions. Due to the worldwide popularity of soccer, these observations
may have important public health implications.