The Clinical Reaction Time (RTclin) test has been recommended as a valid test for assessing concussion and determining recovery of reaction time function following concussion. However, it is unknown whether repeat assessment, as is used in post-concussion testing, is affected by learning or practice phenomena.;;To determine if a practice or learning effect is present with serial administration of the RTclin test.;;Randomized control trial.;;University athletic training clinics.;;One hundred and twelve healthy collegiate athletes (age = 19.46y ± 1.34).;;The control group completed the RTclin test on Days 1 and 60. The experimental group completed the RTclin test on Days 1, 2, 3, 7 and 60.;;Reaction time as measured with the RTclin... test.;;The difference in RTclin test performance from Day 1 to Day 60 was not significant ( Mean Change = -2.77 ± 14.46ms, P = .421, 95%CIs: -6.40, .862 ) between groups. The experimental group experienced significant improvement (λ = .784, F4,49 = 3.365, P= .016, η2= .216, power =.81) with acute repeat testing. However, post-hoc analysis did not reveal a significant difference between scores during the 5 test periods.;;The results suggest serial administration of the RTclin test does not produce a practice or learning effect. Clinicians, however, should be cautious as the results do provide evidence patients may demonstrate improved scores when testing occurs on repetitive days after initial exposure to the test.