Context A mobile application neurocognitive assessment has been used in place of equipment intensive computerized neurocognitive assessment protocol. A previous study reported high to very high test-retest reliability of neurocognitive assessment using the mobile application in healthy adults, but no studies have examined test-retest reliability, reliable change indices (RCIs), and sex effect in middle school and high school populations when conducted 1 year apart. Objective The purpose of this study was to examine the test-retest reliability and RCIs of baseline data collected at 2-time points approximately 1 year apart using a mobile application neurocognitive rest in middle school and high school athletes. The secondary purpose of the study was to investigate the sex difference in neurocognitive measures. Design Cross-sectional study. Setting Institutional. Patients or Other Participants 172 middle school and high school healthy student-athletes (mean age=13.78±1.59 years old). Main Outcome Measure(s) Mobile application neurocognitive rest scores (reaction time, impulse control, inspection, and memory). Results The result from the study demonstrated that neurocognitive measures had low test-retest reliability across a 1-year time period in middle and high school settings. Upon retesting, reaction time and inspection time improved significantly in both middle and high school athletes, and impulse control showed significant improvement in middle school athletes. More athletes in middle school showed more RCI improvements compared to high school athletes. While both males and females demonstrated improvements in neurocognitive measures throughout adolescence, males outperformed females on reaction time and impulse control. Conclusions Findings from the study indicate unacceptably low test-retest reliability of a mobile application neurocognitive test most likely due to cognitive development occurring throughout adolescence. Additionally, significant RCIs were noted. These naturally occurring improvements due to cognitive development could mask the post-concussion deficits. The findings warrant consideration of age and sex on the neurocognitive performance of middle and high school athletes.

Dual-task testing (DT) using laboratory equipment has shown to detect post-concussion deficits even after traditional measures such as neuropsychological and balance tests returned to normal. However, the efficacy of a clinically feasible DT as a concussion evaluation tool remains questionable. Purpose of the study was to compare the clinically feasible DT outcomes between concussed and control participants. Tandem gait (TG) was used as a motor task and the Auditory Pure Switch Task (APST) was used as a cognitive task to compose a clinically feasible DT.   This study was prospective cohort study. Nine concussed athletes diagnosed by a physician and nine control participants with matched characteristics (sex, age, height, weight, and shoe size) from local high schools and a university participated this study. The concussed group completed data collections 7-10 days post-concussion (subacute) and after return to play (RTP). Control group completed the same protocol with a matched timeline. Local high school athletic training rooms and/or university laboratories were used for data collection. TG completion time (sec) was collected as an outcome and the mean of the two trials was utilized for analysis. Mixed-model ANOVA (time x group) was used with an alpha level of p < 0.05.    Concussed group walked significantly slower than control during DT at subacute and after RTP (p = 0.01). This group difference was not indicated during ST (p = 0.11). DT TG was associated with learning effect (p = 0.013), and there was no time by group interaction (ST: p = 0.44, DT: p = 0.51). Our findings suggest that the TG combined with APST detected the group difference that TG alone could not. Concussed athletes took approximately 5 seconds longer to complete DT TG than control even after RTP. A Clinically feasible DT should be considered as an adjunct concussion evaluation to assess the post-concussion deficits and readiness for return to daily and sports activities.