Sport and Team Differences on Baseline Measures of Sport-Related Concussion

Abstract

Context: With the advent of the National Collegiate Athletic Association's (NCAA's) mandating the presence and practice of concussion-management plans in collegiate athletic programs, institutions will consider potential approaches for concussion management, including both baseline and normative comparison approaches.Objective: To examine sport and team differences in baseline performance on a computer-based neurocognitive measure and 2 standard sideline measures of cognition and balance and to determine the potential effect of premorbid factors sex and height on baseline performance.Design: Cross-sectional study. Main Outcome Measure(s): The computerized Concussion Resolution Index (CRI), the Standardized Assessment of Concussion (Form A; SAC), and the Balance Error Scoring System (BESS).Results: Players on the men's basketball team tended to perform worse on the baseline measures, whereas soccer players tended to perform better. We found a difference in total BESS scores between these sports (P ¼ .002). We saw a difference between sports on the hard-surface portion of the BESS (F 6,347 ¼ 3.33, P ¼ .003, g p 2 ¼ 0.05). No sport, team, or sex differences were found with SAC scores (P . .05). We noted differences between sports and teams in the CRI indices, with basketball, particularly the men's team, performing worse than soccer (P , .001) and softball/baseball (P ¼ .03). When sex and height were considered as possible sources of variation in BESS and CRI team or sport differences, height was a covariate for the team (F 1,385 ¼ 5.109, P ¼ .02, g p 2 ¼ 0.013) and sport (F 1,326 ¼ 11.212, P ¼ .001, g p 2 ¼ 0.033) analyses, but the interaction of sex and sport on CRI indices was not significant in any test (P . .05).Conclusions: Given that differences in neurocognitive functioning and performance among sports and teams exist, the comparison of posttraumatic and baseline assessment may lead to more accurate diagnoses of concussion and safer returnto-participation decision making than the use of normative comparisons.Key Words: traumatic brain injuries, baseline assessment, Concussion Resolution Index, Standardized Assessment of Concussion, Balance Error Scoring System Key PointsAssessment of posttraumatic performance in concussion-management programs should be informed by appreciation that premorbid differences related to sport and team membership may exist. Caution should be taken in relying on only 1 or 2 measures because these may be compromised by predictable sport and team differences and demographic factors. Scores on a baseline measure of postural stability (Balance Error Scoring System) and on the computerized Concussion Resolution Index differed by sport, team, and in some cases sex. Differences on the Balance Error Scoring System were correlated with height: taller athletes tended to perform worse than shorter athletes.

What tests and measures should be added to the SCAT3 and related tests to improve their reliability, sensitivity and/or specificity in sideline concussion diagnosis? A systematic review

“…BESS summary scores, the sum of errors from the six stance and surface conditions were evaluated. One study of collegiate athletes found significant variation in BESS performance across sport,44 which was primarily driven by differences in athlete height. Two studies showed that participants performed worse (higher total errors) on the BESS at a live sporting event compared with a controlled locker room or clinical setting 45–47…”

The Sport Concussion Assessment Tool: a systematic review

“…A large fraction of athletes were studied at baseline in an attempt to establish normative data. Two studies have been conducted to establish SCAT 45,46 normative data, 5 for the SCAT2, 13,19,47,50,58 but only 1 for the SCAT3. 16 These studies have reported on variations of the SCAT across ages, sex, and with concussion history.…”

“…19,50,51,57,58 As a number of the early studies utilizing the SAC in an athlete population were conducted on exclusively male football teams, Despite these early reports, more recent studies with athletes have been inconsistent in demonstrating a relationship between sex and SAC scores. Zimmer et al, 58 in a study of SAC scores across various collegiate sport teams, reported no sex differences on the SAC. Yet, in a second study of college athletes by Zimmer et al, 57 females performed significantly better (27.63 vs 26.97; p = 0.004) than males.…”

History of neuropsychological study of sport-related concussion

“…Elbin et al [35] recently determined that athletes that self-reported ADHD, LD or combined ADHD/LD performed worse on a computerized neurocognitive measure and endorsed significantly more concussion-related symptoms at baseline as compared to those who denied ADHD, LD or ADHD/LD [35]. A recent study by Zimmer et al [14] also found that the sport played was associated with differential performance on both the CRI and on a standard test of balance, with sex and height playing important covariate roles. While the NFL, NBA and NHL currently only employ males within their leagues, the importance of understanding the differences in all levels of men's and women's baselines, as well as what differences persist at a post-concussion basis, cannot go overstated.…”

“…Obviously, it is an improbability to eliminate all sources of statistical variance, whether it stems from group averaging or from individual sources. For example, a recent study of several hundred college athletes [14] found that the nature of the sport in which the player was involved is associated with significant performance differences in multiple baseline neurocognitive and balance measures. If post-trauma scores were compared only to group averages, such differences could easily result either in false positive identifications of concussion or, potentially more damaging, misses.…”