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CONTEXT: The Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) is one of the most widely used computerized neurocognitive assessment batteries in athletics, serving as both a baseline and post-injury assessment. It has become increasingly popular to administer the ImPACT baseline test in an un-supervised remote environment, however, it is unknown if the lack of supervision affects the test-retest reliability. OBJECTIVE: To establish the minimal detectable change (MDC) of composite scores from the ImPACT test when administered to National Collegiate Athletic Association (NCAA) Division I student-athletes in an un-supervised remote environment before two consecutive athletic seasons. DESIGN: Cross-Sectional. SETTING: Participants were provided with a unique link and detailed written instructions on how to complete the ImPACT test at home. PATIENTS OR OTHER PARTICIPANTS: NCAA Division I student-athletes. MAIN OUTCOME MEASURE(S): Remote ImPACT baseline test results from the 2020-2021 and 2021-2022 athletic seasons were analyzed. The MDC was calculated at the 95%, 90%, and 80% confidence intervals for each of the ImPACT composite scores, as well as the average and standard deviation. RESULTS: The MDC at the 95% confidence interval was found to be 18.6 for the verbal memory composite score, 24.44 for visual memory, 8.76 for visual motor, 0.14 for reaction time, and 6.13 for impulse control. One-way repeated measures MANOVA, repeated measures ANOVA, and Wilcoxon signed-ranks test all suggest no significant difference between the composite scores and impulse control between time points. CONCLUSIONS: The ImPACT test composite scores and impulse control did not significantly change between the two remote testing time points when administered approximately a year between testing. Our study suggests the MDC serve as a clinician's guide for evaluating changes in ImPACT baseline scores and in making clinical judgments on sports-related concussion when the test is administered at home.
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Background: Facioscapulohumeral muscular dystrophy (FSHD) is a rare genetic muscle disorder leading to progressive muscle loss over time. Research indicates that this progressive muscular atrophy can negatively impact spatio-temporal gait characteristics, but this is not always the case during early-onset or mild cases of the disease. In addition, the performance of a secondary task during overground walking may elucidate greater deficits in spatio-temporal characteristics of gait. However, such dual task effects on FSHD gait have not been studied thus far. Aim: The current study aimed to (a) quantify changes in spatio-temporal gait parameters in individuals with FSHD using the Tekscan Strideway gait mat system, (b) measure the dual task (DT) effects on cadence and gait velocity during single task (ST) and DT overground walking in FSHD and healthy controls and (c) investigate the correlation between the gait parameters and the methylation status in FSHD. Methods: Nine FSHD (M±SD=52.78±14.69 years) and nine nearly matched healthy controls (M±SD=50.11±16.18 years) performed five ST and five DT walking in a pseudo-randomized order. The DT included a serial 7's subtraction task from a random number between 50 and 100. Dependent variables: Cadence (steps/min) and gait velocity (cm/sec) were obtained from Tekscan Strideway (30 Hz, Boston, MA). Results: The pairwise comparison indicated that cadence was significantly different for both ST (P<0.004) and DT (P<0.02) where FSHD showed lower cadence compared to controls. Gait velocity was also significantly lower for FSHD during ST (P<0.004) and DT (P<0.008). Multilevel modeling (MLM) approach revealed a group by task interaction for cadence (P<0.05) and gait velocity (P<0.001). The interaction showed a significant difference between ST and DT in controls for cadence and gait velocity. However, there was no difference between ST and DT in FSHD. Finally, a comparison of methylation percentage versus gait parameters revealed a significant negative correlation coefficient for cadence but not for gait velocity. Conclusion: These results indicate specific pairwise differences in both ST and DT walking, observed in the gait parameters as decreased cadence and gait velocity during ST and DT. In addition, the MLM showed that controls exhibited the DT cost as expected but FSHD did not for cadence and gait velocity. Relevance for Patients: ST appears to be sufficiently challenging in FSHD and results in overall declines in spatio-temporal characteristics of gait. Further research is needed to test this paradigm with early-onset or mild cases to track disease progression and its effects on ambulation.