This study was conducted to determine the long-term relatability of ImPACT scores among young athletes. Youth sport participants (n=294) who completed ImPACT tests one year apart were included in the study. Ages ranged from nine to 14 with a mean of 11.42 (SD = .96). The majority (n = 215) were males. Test-retest reliabilities for verbal memory, visual memory, response time, and impulse control were statistically significant but weak, ranging between .33 and .49. The index score had poor test-retest reliabilities (r = .26). Visual-motor test-retest reliability was also significant but moderate (r=.68). Scores for the verbal memory subtest and the index score did not change over time. However, there was significant improvement for the visual memory (t(293) = 2.24, p < .03, d = .13), visualmotor (t(293) = 9.23, p < .001, d = .54), response time (t(293) = 3.78, p < .001, d = .22), and impulse (t(293) = 3.27, p < .001, d = .19) subtests. These results indicate that the long-term test-retest reliability of the ImPACT is inadequate and that several subtests change over time. Therefore, it is recommended that baseline ImPACT scores are obtained on an annual basis.
Koch, Christopher and Robertson, Sean, "Reliability and Test Differences for the Impact: Implications for Concussion Testing Programs" (2019). Faculty Publications - Psychology Department. 60.