Robust RT deficits were observed acutely following concussion .
Minimal magnitude differences were noted when comparing between- and within-subject effects , suggesting that pre-injury baselines may not add clinical value in determining post-injury RT impairment .
RT deficits persisted up till the intermediate-term ( 21–59 days post-injury ) timeframe and indicate lingering deficits exist .
Mean effect size differences were observed between RT measure types and computerized neurocognitive testing platforms ; however , all categories displayed negative effects consistent with impaired RT following concussion .
Reaction time ( RT ) deficits are reported following concussion , but it is unknown when these deficits normalize to pre-injury status .
It is also unclear how factors such as RT measurement technique and participant characteristics influence post-concussion RT .
The purpose of this systematic review and meta- analysis was to ( 1 ) characterize acute post-concussion ( 0–3 days ) RT impairments , ( 2 ) examine RT recovery over time , and ( 3 ) explore moderating factors related to acute RT impairment following concussion .
Effect of concussion on clinically measured reaction time in 9 NCAA division I collegiate athletes: a preliminary study.
OBJECTIVES To evaluate the effect of concussion on clinical ly measured reaction time ( RT(clin ) ) and in comparison to a computerized reaction time measure ( RT(comp ) ) . DESIGN Prospect i ve , repeated measures observational study . SETTING Athletic training clinic at a National Collegiate Athletic Association ( NCAA ) Division I university . PARTICIPANTS Data are reported for 9 collegiate athletes with acute concussion who were part of a larger cohort of 209 athletes recruited from the university 's football , women 's soccer , and wrestling teams before the start of their respective athletic seasons . METHODS  Baseline RT(clin ) and RT(comp )  were measured during preparticipation physical examinations . RT(clin ) measured the time required to catch a suspended vertical shaft by h and closure after its release by the examiner . RT(comp ) was derived from the simple RT component of the CogState-Sport computerized neurocognitive test battery . Athletes who subsequently sustained a physician-diagnosed concussion underwent repeated RT(clin ) and RT(comp ) testing within 72 hours of injury . A Wilcoxon signed rank test was used to compare baseline and after-injury RTs . MAIN OUTCOME MEASUREMENTS After-injury changes in RT(clin ) and RT(comp ) were calculated with respect to each athlete 's own preseason baseline value . RESULTS After-injury RT(clin ) was prolonged in 8 of the 9 athletes with concussions , whereas RT(comp ) was prolonged in 5 of the 9 athletes with concussions . The mean ( st and ard deviation ) RT(clin ) increased from 193 ± 21 ms to 219 ± 31 ms ( P = .050 ) , and mean RT(comp ) increased from 247 ± 75 to 462 ± 120 ms ( P = .214 ) . CONCLUSIONS We concluded that RT(clin ) appears to be sensitive to the known prolongation of RT after concussion and compares favorably with an accepted computerized RT measure . This study supports the potential utility of RT(clin ) as part of a multifaceted concussion assessment battery
Robust RT deficits were observed acutely following concussion .
Minimal magnitude differences were noted when comparing between- and within-subject effects , suggesting that pre-injury baselines may not add clinical value in determining post-injury RT impairment .
RT deficits persisted up till the intermediate-term ( 21–59 days post-injury ) timeframe and indicate lingering deficits exist .
Mean effect size differences were observed between RT measure types and computerized neurocognitive testing platforms ; however , all categories displayed negative effects consistent with impaired RT following concussion .
Reaction time ( RT ) deficits are reported following concussion , but it is unknown when these deficits normalize to pre-injury status .
It is also unclear how factors such as RT measurement technique and participant characteristics influence post-concussion RT .
The purpose of this systematic review and meta- analysis was to ( 1 ) characterize acute post-concussion ( 0–3 days ) RT impairments , ( 2 ) examine RT recovery over time , and ( 3 ) explore moderating factors related to acute RT impairment following concussion .