ImPACT Normative Data of Ethnically Diverse Adolescent Athletes

Population-based normative data and language effects of the Immediate Post-Concussion Assessmentand Cognitive Testing (ImPACT)

OBJECTIVE

When test results are interpreted based on the norms of the U.S. population, misdiagnoses of neurocognitive impairment could occur with subgroups of individuals whose demographic characteristics differ from the overall population. The present study compared locally-based normative test data of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) of high school athletes in Hawaii, where diverse ethnicity and bilingualism are prominent, versus published test norms.

METHOD

8637 high school athletes in Hawaii underwent ImPACT baseline testing. Non-parametric group comparisons of age, sex, and language groups were performed. Classification ranges for the ImPACT Composite scores and Total Symptom of the Hawaii sample were presented in percentile ranks that corresponded to the published ImPACT normative tables.

RESULTS

Mann-Whitney U Test indicated significant differences in ImPACT Verbal Memory, Visual Memory, Visual Motor Speed, and Reaction Time Composite scores between age groups and sexes, although the effect sizes were small. Kruskal-Wallis H Test indicated no differences among the language groups. Percentile ranks of the Hawaii scores were predominantly similar to the ImPACT norms, except for Visual Motor Speed in the Impaired and Borderline ranges.

CONCLUSION

The findings suggest that locally based normative data should be considered for sub-populations that may differ from the general population. Language factors, such as bilingualism, did not have significant effect on the ImPACT scores.

Quantifying the Diagnostic Utility of Baseline Testing in Concussion Management: An Analysis of Collegiate Athletes From the NCAA-DoD CARE Consortium Dataset

BACKGROUND

Although preseason baseline testing is a commonly recommended part of the concussion management process, its "value-added" contribution to the diagnosis of acute concussion compared with normative reference values remains in question.

PURPOSE

This research aimed to evaluate the diagnostic benefits of baseline testing in acute concussion assessment compared with normative reference values and characterize the athletes who receive the most diagnostic utility from baseline testing.

STUDY DESIGN

Cohort study (Diagnosis); Level of evidence, 2.

METHODS

The investigators selected athletes from the National Collegiate Athletic Association-Department of Defense (NCAA-DoD) Concussion Assessment, Research, and Education (CARE) Consortium with at least 2 baseline assessments and 1 concussion. Two predictive models were developed that mimic acute concussion assessment using multivariate logistic regression based on a battery of postural control, neurocognitive status, and symptom assessments. The first predictive model gives a concussion status prediction based on change scores computed using individualized baseline testing information, whereas the second model uses normative reference values. The investigators defined and computed a novel metric called the Diagnostic Utility of Baseline Testing by comparing the concussion status predicted by each of these predictive models. The Diagnostic Utility of Baseline distribution was analyzed across athlete demographic characteristics and medical history.

RESULTS

The study included 1081 collegiate athletes (43.9% female) with 1279 acute concussion assessments (24- to 48-hour postinjury assessments) and 1551 reference assessments (baseline and 6-month assessments). Both the baseline and normative models exhibited notably high area under the curve values of .89 and .90, respectively. Most athletes (86.7%) did not gain additional diagnostic benefits from baseline testing versus normative values. Those with Hispanic ethnicity (P = .038) or a history of psychiatric disorders (P < .001) or depression (P = .002) were more likely to be correctly identified as having acute concussion when change scores were derived from normative values instead of individualized baseline values.

CONCLUSION

This study highlights that the additional diagnostic benefit of preseason baseline testing over normative data is limited for most collegiate student-athletes. Thus, normative data can be used for most collegiate student-athletes in the absence of baseline testing. Moreover, these results can inform decisions on the allocation of baseline tests in resource-limited athletic settings, emphasizing the need for targeted concussion assessment strategies based on individual characteristics.

Sex comparisons in neuropsychological functioning and reported symptoms following a sports-related concussion among high school athletes

The aim of this study was to compare the neuropsychological functioning and symptoms of female and male high school athletes following a single concussion during the school year. The baseline test scores of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) of 309 concussed athletes (169 females, 221 males) in varied sports were obtained. After a sport-related concussion, the athletes were re-administered the ImPACT, on the average, 7.25 days after the injury. MANCOVA compared the ImPACT baseline scores, post-concussion scores, and baseline-to-post-concussion changes of the female and male athletes, with p set at 0.01. The only significant sex comparison found females performing better on baseline visual motor speed (p < 0.001). Otherwise, no sex differences were found in baseline test scores, post-concussion scores, and baseline-to-post-concussion changes. The findings tentatively suggest that there are insignificant sex differences in the consequences of sport-related concussion after a week post-injury. Future studies on sex comparisons after a concussion are needed focusing on the acute and sub-acute phases of the recovery period.