Baseline Performance of NCAA Athletes on a Concussion Assessment Battery: A Report from the CARE Consortium

Sport-Related Concussions in High School Athletes: A Comprehensive Update

PURPOSE OF REVIEW

Sport-related concussions (SRC) in high school athletes are a growing public health concern, with recent advancements in epidemiology, pathophysiology, diagnosis, management, and prevention. We concisely summarize SRC in high school athletes, emphasizing current research and clinical implications.

RECENT FINDINGS

Athletes are at significant risk of SRCs, with incidence varying by sport, sex, and competitive setting. Advances in pathophysiology highlight the role of metabolic disruption, inflammation, and axonal injury. Updated diagnostic tools, such as SCAT6, aid clinical evaluation, while advanced neuroimaging and biomarkers remain investigational. Return-to-sport/learn protocols emphasize a gradual, stepwise return. Preventative measures, including policy changes, neuromuscular training, and protective equipment, have reduced SRC incidence. Comprehensive SRC management includes recognition and removal from play followed by a structured return to sport/learning. Future research directions include biomarker validation, optimized prevention strategies, and long-term outcome assessment to reduce the burden of SRC in adolescent athletes.

Sport Concussion Assessment Tool-5th Edition (SCAT5) normative reference values for professional men's rugby league players

OBJECTIVES

To provide normative reference values for the Sport Concussion Assessment Tool - 5th Edition for elite-level male rugby league players.

DESIGN

A descriptive cross-sectional study.

METHODS

Baseline Sport Concussion Assessment Tool - 5th Edition scores were obtained from 1005 National Rugby League players during the 2018 and 2019 preseasons. Normative values were calculated for the Standardized Assessment of Concussion, Symptom Evaluation (i.e., severity and number), and the Modified Balance Error Scoring System for each group and in total. Players self-identified their cultural heritage or ethnicity to be 'Pasifika (Pacific Islander) or Maori' (n = 243; 24.2 %) or 'Indigenous Australian' (n = 82; 8.2 %). Those who identified as any other race, ethnicity, or cultural heritage were combined into a single group (n = 680; 67.7 %).

RESULTS

In total the median Standardized Assessment of Concussion score was 27 (interquartile range = 25-28), the median symptom severity was 0 (interquartile range = 0-2), the median symptom number was 0 (interquartile range = 0-1), and the median the Modified Balance Error Scoring System error score was 3 (interquartile range = 1-5). Reporting 4 of 22 symptoms and 6 of 132 on the total severity score was uncommon. There was no significant difference between the cultural heritage or ethnicity groups for Standardized Assessment of Concussion scores, symptom severity or number, or Modified Balance Error Scoring System errors (p-values >0.05).

CONCLUSIONS

This normative data will assist with the clinical interpretation of Sport Concussion Assessment Tool - 5th Edition scores following a concussion in the National Rugby League.

Associations among perceived stress and mindfulness on post-concussion cognitive and mental health outcomes in young adults with a concussion history

BACKGROUND

Despite evidence suggesting perceived stress negatively impacts post-concussion outcomes and that mindfulness may improve that relationship, research has not investigated those connections.

METHODS

This cross-sectional, observational study included 80 young adults with a concussion history who completed a single study visit including the following measures: 1) demographics and concussion, mental health, and mindfulness histories; 2) perceived stress [Perceived Stress Scale (PSS-10)]; 3) mindfulness [Five Facet Mindfulness Questionnaire (FFMQ)]; and 4) post-concussion cognitive and mental health outcomes - neurocognitive performance (CNS Vital Signs), psychological symptoms [Brief Symptom Inventory-18 (BSI-18)], and QOL [Patient-Reported Outcomes Measurement Information System (PROMIS®)]. First, separate regression models determined the association among perceived stress and post-concussion cognitive and mental health outcomes. Second, linear regression models determined the association among mindfulness and post-concussion cognitive and mental health outcomes. Third, to test the moderation effect, models included a perceived stress and mindfulness interaction term.

RESULTS

Higher perceived stress was significantly associated with higher psychological symptoms (p < 0.001) and lower QOL (p < 0.05). Higher mindfulness was significantly associated with lower psychological symptoms (p < 0.001) and higher QOL (p < 0.05). No moderation models were significant.

CONCLUSION

Future research is necessary to further understand mechanisms impacting post-concussion interventions aimed to improve outcomes and life post-concussion.

Baseline concussion assessment performance by sex in military service academy rugby players: findings from the CARE Consortium

BACKGROUND

Normative student-athlete concussion assessment data may not be appropriate for service academy members (SAMs), particularly rugby players, because of the uniqueness of their academic/military training environment. Having accurate baseline data for this population is important because of their high risk for concussion and frequent lack of assigned sports medicine professional. The primary purpose of this study was to characterise baseline performance on a concussion assessment battery, with secondary purpose to determine effect of sex and concussion history on these measures among SAM rugby players.

METHODS

601 rugby-playing SAMs (19.3±1.5 years, 37.9% female) completed baseline concussion assessments: the Sport Concussion Assessment Tool (SCAT) Symptom and Symptom Severity Checklist, Standard Assessment of Concussion (SAC) and a neuropsychological test (either ImPACT (Immediate Post Concussion Assessment and Cognitive Testing) or ANAM (Automated Neuropsychological Assessment Metrics)). Groups were compared using an independent samples t-test or Mann-Whitney U test. A 2 (sex) × 2 (concussion history) ANOVA was conducted to determine the effects of sex and concussion history on outcomes.

RESULTS

Women reported greater SCAT total symptoms (3.3 vs 2.8, p<0.001, r=0.143) and symptom severities (5.7 vs 4.3, p<0.001, r=0.139), and performed worse on ImPACT Visual Memory (79.3 vs 82.6, p=0.002, r=0.144) than men. Women performed better than men on SAC (28.0 vs 27.7, p=0.03, r=0.088), ImPACT Reaction Time Composite (0.59 vs 0.61, p=0.04, r=0.092) and ANAM Code Substitution Delayed (64.3 vs 61.5, p=0.04, d=0.433). Individuals with a history of concussion reported lower ImPACT Symptom Severity (2.6 vs 4.2, p=0.02, r=0.110). There was no interaction between concussion history and sex on outcomes.

CONCLUSIONS

These findings provide reference data for SAM rugby players on baseline assessments and to help in clinical decision-making when managing sports-related concussion in absence of baseline data.

SCAT Symptom Evolution in the Acute Concussion Phase: Findings from the NCAA-DoD CARE Consortium

The Sport Concussion Assessment Tool (SCAT) is the most widely used tool following sport-related concussion (SRC). Initial SCAT symptom burden is a strong predictor of recovery in collegiate athletes; however, it is unknown if symptom presentation varies within the acute (<48 h) post-SRC phase. The purpose of this cohort study was to examine acute SRC symptom presentation among the National Collegiate Athletic Association (NCAA) athletes. Concussed NCAA varsity athletes (n = 1,780) from 30 universities across the United States, which participated in the Concussion Assessment, Research, and Education (CARE) Consortium, were included. Time of injury occurrence and SCAT administration data were recorded, from which time-to-SCAT (hours, continuous) was calculated. The main outcome was SCAT total symptom severity [(TSS), 0-126]. Multivariable negative binomial regression was used to examine the association between time (hours) since injury and TSS. Covariates included sex, previous concussion, sport contact level, amnesia/loss of consciousness, immediate reporting of injury, and injury situation. A random effect (person level) accounted for multiple assessments. TSS score ratios (SR) with associated 95% confidence intervals (CI) were provided. The SCAT was administered an average of 14 (25th-75th percentile: 1.2-24) hours post-SRC, and average TSS was 27.35 ± 21.28 across all participants. Time-to-SCAT was associated with a 1% decrease in TSS after adjusting for covariate effects (SR: 0.99, 95% CI: 0.99-0.99, p < 0.001). Overall, we observed a small, but significant decrease in TSS with each hour post-SRC. Assessing a concussed athlete once in the acute phase will likely provide a sufficient sense of their symptomatic well-being, as measures did not fluctuate dramatically. Future research should aim to examine how acute symptom evolution influences recovery metrics.

Prior Concussion History and Clinical Recovery Following Sport-Related Concussion in College Athletes

OBJECTIVE

The aim of this study was to assess whether a history of prior concussions, and especially multiple prior concussions, is associated with clinical recovery following a subsequent sport-related concussion among collegiate student athletes.

DESIGN

A naturalistic observational cohort study.

SETTING

Eleven National Collegiate Athletics Association Division III colleges.

PARTICIPANTS

Collegiate athletes sustaining concussions from September 2014 through March 2020.

INDEPENDENT VARIABLES

Participants were divided into 3 groups, athletes with: (1) no prior concussion history, (2) one prior concussion, and (3) 2 or more prior concussions.

MAIN OUTCOME MEASURES

Survival analyses were used to compare time to return to school and sports among athletes with a history of 0, 1, or ≥2 prior concussions.

RESULTS

Among the 1132 college athletes, there were no statistically significant group differences between those with 0, 1, or ≥2 prior concussions in total time to return to school or sports. There was a statistically significant difference in the proportion of athletes with ≥2 prior concussions that had not fully returned to school, without accommodations, at 28 days (6.0%) compared to athletes with no prior concussions (2.2%; odds ratio = 2.80, 95% confidence interval 1.29-6.04).

CONCLUSIONS

In summary, concussion history was not associated with time to return to sports following a subsequent sport-related concussion in these college athletes. On average, athletes with prior concussions did not take longer to return to school, although a slightly greater proportion of college athletes with ≥2 prior concussions had not fully returned to school, without accommodations, by 28 days following injury.

Profile of brief symptom inventory-18 (BSI-18) scores in collegiate athletes: A CARE Consortium study

Objective: The goal of this study was to characterize normative scores for the Brief Symptom Inventory (BSI-18) in collegiate athletes to inform decision making about the need for psychological health services in this group. Methods: Collegiate student-athletes (N = 20,034) from 25 universities completed the BSI-18 at their preseason baseline assessment. A subgroup (n = 5,387) underwent multiple baseline assessments. Global Severity Index (GSI) scores were compared to community norms and across multiple timepoints. Results: Collegiate athletes reported significantly lower GSI scores than published community norms (p<.001). Published GSI threshold scores for "caseness", identified only 2 per 100 athletes (≥ the 98th percentile) as needing further evaluation. Using a GSI score ≥ than the cohort's 90th percentile, 11.4 per 100 athletes would merit additional evaluation. These individuals were more likely to report a history of psychiatric diagnosis (Odds ratio [95% CI] 2.745 [2.480, 3.039]), as well as ≥ 2 prior concussions (p<.001). GSI scores were not highly correlated across timepoints. Suicidal ideation was rare (n = 230; 1.15%). Conclusions: For collegiate student-athletes, published BSI-18 threshold scores identify only extreme outliers who might benefit from additional behavioral health evaluation. Alternatively, use of threshold scores ≥ the 90th percentile identifies a more realistic 11.4% of the population, with higher likelihood of prior concussion and/or psychiatric disorders.

Mental health symptom burden in elite ice hockey players and its association with self-reported concussive events

BACKGROUND

Some studies suggest that elite athletes experience adverse mental health symptoms at rates commensurate with the general population, despite the well-established buffering effects of exercise. Within contact sports, such as ice-hockey, recurrent concussions may be a source of this discrepancy. We compared the point prevalence of various mental health outcomes with other athlete and general population samples, as well as investigated their relationship with concussive events.

METHODS

We surveyed 648 active ice hockey players from the top two men's tiers and the top women's tier in Swedish elite ice hockey on lifetime concussive events, hazardous alcohol use, problematic social media use, depression, anxiety, and burnout.

RESULTS

Hazardous alcohol use was more prevalent among male ice hockey players (29.5% AUDIT-C ≥ 6) compared to other athlete and general population samples, while other mental health symptoms were less common. Female ice hockey players reported higher hazardous alcohol consumption (36.4% AUDIT-C ≥ 4) than another athlete sample and more burnout (19.1%) than the general population. After adjusting for covariates, athletes with 3+ concussive events had 2.1 times the odds of elevated depressive symptoms and 3.5 times the odds of elevated burnout symptoms compared to those with no concussion history. Treating lifetime concussive events as a continuous predictor revealed positive correlations with all outcomes except for hazardous alcohol use.

CONCLUSIONS

Mental health outcome rates among active elite ice hockey athletes differ from those of other athlete and general population samples, whilst concussive events may be particularly linked to elevated symptoms of depression and burnout.

Multiparameter cortical surface morphology in former amateur contact sport athletes

The lifetime effects of repetitive head impacts have captured considerable public and scientific interest over the past decade, yet a knowledge gap persists in our understanding of midlife neurological well-being, particularly in amateur level athletes. This study aimed to identify the effects of lifetime exposure to sports-related head impacts on brain morphology in retired, amateur athletes. This cross-sectional study comprised of 37 former amateur contact sports athletes and 21 age- and sex-matched noncontact athletes. High-resolution anatomical, T1 scans were analyzed for the cortical morphology, including cortical thickness, sulcal depth, and sulcal curvature, and cognitive function was assessed using the Dementia Rating Scale-2. Despite no group differences in cognitive functions, the contact group exhibited significant cortical thinning particularly in the bilateral frontotemporal regions and medial brain regions, such as the cingulate cortex and precuneus, compared to the noncontact group. Deepened sulcal depth and increased sulcal curvature across all four lobes of the brain were also notable in the contact group. These data suggest that brain morphology of middle-aged former amateur contact athletes differs from that of noncontact athletes and that lifetime exposure to repetitive head impacts may be associated with neuroanatomical changes.

Return to Play Following Concussion: Role for Imaging?

This review surveys concussion management, focusing on the use of neuroimaging techniques in return to play (RTP) decisions. Clinical assessments traditionally were the foundation of concussion diagnoses. However, their subjective nature prompted an exploration of neuroimaging modalities to enhance diagnosis and management. Magnetic resonance spectroscopy provides information about metabolic changes and alterations in the absence of structural abnormalities. Diffusion tensor imaging uncovers microstructural changes in white matter. Functional magnetic resonance imaging assesses neuronal activity to reveal changes in cognitive and sensorimotor functions. Positron emission tomography can assess metabolic disturbances using radiotracers, offering insight into the long-term effects of concussions. Vestibulo-ocular dysfunction screening and eye tracking assess vestibular and oculomotor function. Although these neuroimaging techniques demonstrate promise, continued research and standardization are needed before they can be integrated into the clinical setting. This review emphasizes the potential for neuroimaging in enhancing the accuracy of concussion diagnosis and guiding RTP decisions.

Collegiate Athletes With Diabetes: Baseline Medical Comorbidities and Preseason Concussion Testing Performance

CONTEXT

People with diabetes mellitus (DM) are at increased risk for adverse health events and complications throughout their lifetime. Whether DM significantly affects collegiate athletes' concussion baseline testing performance remains unclear.

OBJECTIVES

To (1) describe the prevalence of DM and associated comorbidities and (2) compare concussion baseline testing performance between student-athletes with DM and student-athletes without DM (NoDM).

DESIGN

Retrospective, cross-sectional study.

SETTING

University.

PATIENTS OR OTHER PARTICIPANTS

Using the Concussion, Assessment, Research and Education (CARE) Consortium research database, we matched athletes with self-reported DM (N = 229) by institution, sex, age, sport, position, testing year, and concussion history to athletes with NoDM (N = 229; total sample mean age = 19.6 ± 1.4 years, women = 42%).

MAIN OUTCOME MEASURE(S)

Descriptive statistics and χ2 tests of independence with subsequent odds ratios were calculated. Independent-samples t tests compared baseline symptoms, neurocognitive testing, and balance performance between athletes with DM and athletes with NoDM. Effect sizes were determined for significant group differences.

RESULTS

At baseline, athletes with DM had higher rates of self-reported pre-existing balance disorders, sleep disorders, seizure disorders, motion sickness, learning disorders, vision and hearing problems, psychiatric disorders, depression, bipolar disorder, nonmigraine headaches, and meningitis than athletes with NoDM (P values < .05). We found balance differences between groups (P = .032, Cohen d = 0.17) such that, on average, athletes with DM had 1 additional error on the Balance Error Scoring System (DM = 13.4 ± 6.5; NoDM = 12.1 ± 5.9). No other comparisons yielded significant results.

CONCLUSIONS

Although athletes with DM had high rates of self-reported balance disorders, sleep disorders, seizures, and meningitis, their baseline neurocognitive testing results were largely identical to those of athletes with NoDM. Our findings suggested that nonclinically meaningful differences were present in concussion baseline balance testing but no significant differences were noted in cognitive testing; however, the effect of DM on concussion recovery remains unknown.

Return to Sports Following Sports-Related Concussion in Collision Sports: An Expert Consensus Statement Using the Modified Delphi Technique

PURPOSE

To perform a Delphi consensus for return to sports (RTS) following sports-related concussion (SRC).

METHODS

Open-ended questions in rounds 1 and 2 were answered. The results of the first 2 rounds were used to develop a Likert-style questionnaire for round 3. If agreement at round 3 was ≤80% for an item, if panel members were outside consensus or there were >30% neither agree/disagree responses, the results were carried forward into round 4. The level of agreement and consensus was defined as 90%.

RESULTS

Individualized graduated RTS protocols should be used. A normal clinical, ocular and balance examination with no more headaches, and asymptomatic exertional test allows RTS. Earlier RTS can be considered if athletes are symptom free. The Sports Concussion Assessment Tool 5 and vestibular and ocular motor screening are recognized as useful tools to assist in decision-making. Ultimately RTS is a clinical decision. Baseline assessments should be performed at both collegiate and professional level and a combination of neurocognitive and clinical tests should be used. A specific number of recurrent concussions for season-or career-ending decisions could not be determined but will affect decision making for RTS.

CONCLUSIONS

Consensus was achieved for 10 of the 25 RTS criteria: early RTS can be considered earlier than 48 to 72 hours if athletes are completely symptom-free with no headaches, a normal clinical, ocular and balance examination. A graduated RTS should be used but should be individualized. Only 2 of the 9 assessment tools were considered to be useful: Sports Concussion Assessment Tool 5 and vestibular and ocular motor screening. RTS is mainly a clinical decision. Only 31% of the baseline assessment items achieved consensus: baseline assessments should be performed at collegiate and professional levels using a combination of neurocognitive and clinical tests. The panel disagreed on the number of recurrent concussions that should be season- or career-ending.

LEVEL OF EVIDENCE

Level V, expert Opinion.

Estimating the Relationship Between the Symptom-Free Waiting Period and Injury Rates After Return-to-Play from Concussion: A Simulation Analysis Using CARE Consortium Data

BACKGROUND

A key component of return-to-play (RTP) from sport-related concussion is the symptom-free waiting period (SFWP), i.e., the period during which athletes must remain symptom-free before permitting RTP. Yet, the exact relationship between SFWP and post-RTP injury rates is unclear.

OBJECTIVE

We design computational simulations to estimate the relationship between the SFWP and rates of repeat concussion and non-concussion time-loss injury up to 30 days post-RTP for male and female collegiate athletes across 13 sports.

METHODS

We leverage N = 735 female and N = 1,094 male post-injury trajectories from the National Collegiate Athletic Association-Department of Defense Concussion Assessment, Research, and Education Consortium.

RESULTS

With a 6-day SFWP, the mean [95% CI] rate of repeat concussion per 1,000 simulations was greatest in ice hockey for females (20.31, [20.16, 20.46]) and American football for males (24.16, [24.05, 24.28]). Non-concussion time-loss injury rates were greatest in field hockey for females (153.66, [152.59, 154.74]) and wrestling for males (247.34, [246.20, 248.48]). Increasing to a 13-day SFWP, ice hockey for females (18.88, [18.79, 18.98]) and American football for males (23.16, [23.09, 24.22]) exhibit the greatest decrease in repeat concussion rates across all sports within their respective sexes. Field hockey for females (143.24, [142.53, 143.94]) and wrestling for males (237.73, [236.67, 237.90]) exhibit the greatest decrease in non-concussion time-loss injury rates. Males receive marginally smaller reductions in injury rates for increased SFWP compared to females (OR = 1.003, p ≤ 0.002).

CONCLUSION

Longer SFWPs lead to greater reductions in post-RTP injury rates for athletes in higher risk sports. Moreover, SFWPs should be tailored to sport-specific post-RTP injury risks.

Does Frequency of Baseline Testing Influence Concussion Diagnostic Decision Making Among College Athletes

OBJECTIVE

Concussion is a growing public health concern given the large number of youth and collegiate athletes participating in collision sports. Sport-related concussions can have an adverse impact on student-athletes' health and academic performance. Athletic programs within academic organizations are motivated to employ the most effective and efficient diagnostic and recovery procedures to minimize the duration and impact of these symptoms on student-athletes' functioning. The present study sought to further our understanding regarding the value and frequency of conducting baseline assessments when evaluating sport-related concussions.

METHOD

A total of 41 athletes (24 men, 17 women) between the ages of 18 and 22 were evaluated following suspected concussive injury between 2015 and 2018. Post-injury test results were compared to baselines that had been collected either 1 or 2 years prior, and to normative data, to determine consistency in diagnostic outcomes.

RESULTS

Baseline test/retest reliability using Pearson's bivariate correlations revealed modest correlations on measures of verbal and visual memory (0.437-0.569) and very strong correlations on measures of reaction time and visual-motor speed (0.811-0.821). Meanwhile, minimal if any differences in clinical decision-making regarding the diagnostic outcome was observed when comparing post-injury test results to different baselines and to normative data.

CONCLUSIONS

Findings indicate that yearly baseline testing may not improve diagnostic accuracy, and in many cases, normative data may be adequate for decision-making. Additional research should evaluate the potential benefit of baseline testing in return-to-play decision-making among broader athletic populations.

Baseline Evaluation of Concussion-Like Symptoms and Modifying Factors in Collegiate Club-Sport Athletes

CONTEXT

Collegiate club-sport athletes participate in a variety of competitive sports and have been understudied in the concussion literature. Baseline performance measures are warranted to better understand assessment and management.

OBJECTIVE

To quantify normative values and the effects of modifying factors sex, concussion history, diagnosed attention disabilities (attention-deficit/hyperactivity disorder [ADHD]), and sport type on baseline symptom evaluation among collegiate club-sport athletes.

DESIGN

Cross-sectional study.

SETTING

Retrospective chart review.

PATIENTS OR OTHER PARTICIPANTS

A total of 1034 collegiate club-sport athletes (N = 649 males, 62.7%) from 29 sports at a single institution.

MAIN OUTCOME MEASURE(S)

Chart reviews were conducted for club-sport athletes who completed athlete background and symptom information on the Sport Concussion Assessment Tool-5th edition as a baseline concussion assessment during a single academic year. Demographics (eg, age, sex, sport), background medical information (eg, concussion history, ADHD), and symptom evaluation, consisting of individual 22-item symptom reports, the total number of symptoms, symptom severity scores, and symptom factors (eg, physical, cognitive, insomnia, and emotional), were analyzed.

RESULTS

On baseline symptom reporting, 68% of club-sport athletes were asymptomatic, with mild symptoms described by 3% to 12% and moderate or severe symptoms by ≤4%. Modifier groups differed with a higher total number of symptoms and symptom severity in females (P < .001), individuals reporting a history of concussion (P < .001), and those with ADHD (total number P = .04, symptom severity P = .02). Similar significant findings were noted for females and the history of concussion group on all 4 symptom factors; however, those in collision or contact sports also indicated greater cognitive (P = .03) and insomnia (P = .02) factors. Those with ADHD endorsed more cognitive (P < .001) factors.

CONCLUSIONS

Normative symptoms for a collegiate club-sport sample revealed approximately 70% were asymptomatic. Higher total number of symptoms and symptom severity were demonstrated by females and those with a history of concussion. Cognitive-specific symptoms were greater in those diagnosed with ADHD and those who participated in collision or contact sports.

Self-Reported Mental Health Measures of Incoming Collegiate Student-Athletes With a History of COVID-19

BACKGROUND

People with a history of COVID-19 may experience persistent neuropsychological disruptions such as lower satisfaction with life, depression, and anxiety. Although student-athletes are at low risk for severe COVID-19 complications, the effect of COVID-19 on mental health has not been elucidated.

OBJECTIVE

To compare patient-reported mental health outcomes for incoming collegiate athletes with (COVID+) or without (COVID-) a history of COVID-19.

DESIGN

Case-control study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 178 student-athletes, consisting of 79 in the COVID+ group (44.3%; age = 18.90 ± 0.16 years) and 99 in the COVID- group (55.6%; age = 18.95 ± 0.16 years).

MAIN OUTCOME MEASURE(S)

Participants completed the Satisfaction With Life Scale (SWLS), the Hospital Anxiety and Depression Scale (HADS), and the State-Trait Anxiety Inventory (STAI). Unadjusted 1-way analyses of variance were conducted across all patient-reported outcomes. Analyses of covariance were calculated to determine the interaction of COVID-19 group, sex, and race and ethnicity on outcomes. Post hoc Bonferroni testing was performed to identify specific differences between groups. A χ2 analysis was computed to compare the number of athletes in each group who met the standard clinical cut points.

RESULTS

We observed a between-groups difference for HADS depression (P = .047), whereby athletes in the COVID+ group had higher ratings (2.86 ± 0.26). We found group differences for the SWLS (P = .02), HADS anxiety (P = .003), and STAI state anxiety (P = .01) such that all scores were higher for the COVID+ group in the adjusted model. Post hoc testing revealed that female student-athletes in the COVID+ group had worse HADS anxiety (P = .01) and STAI trait anxiety (P = .002) scores than individuals in all other groups. We did not demonstrate differences between groups in the percentage of responses below established diagnostic thresholds.

CONCLUSIONS

Incoming collegiate student-athletes who reported a previous COVID-19 diagnosis displayed higher depression scores, suggesting that clinicians may need to provide appropriate identification and referral for mental health conditions. However, we were encouraged that most participants, regardless of a history of COVID-19 diagnosis, had mental health scores that did not exceed established diagnostic threshold values.

National Collegiate Athletic Association athletic trainers' response to the Arrington settlement: management, compliance, and practice patterns

The primary purpose of this study was to assess Athletic Trainers' (ATs) report of NCAA member institution compliance with the Arrington settlement, the concussion lawsuit vs. the NCAA, and to elucidate compliance predictors. A secondary purpose was to provide a contemporary concussion management clinical practice pattern description among NCAA collegiate athletic trainers. Head Athletic Trainers from NCAA Division I, II, and III completed an electronic questionnaire in August 2020 regarding their institution's response to the Arrington Settlement and their current concussion management clinical practice patterns. The 37-item questionnaire included AT and institution demographics, current concussion management policies, and response to the Arrington settlement with a specific focus on the five settlement requirements. An overall compliance score on the five requirements, compliance on the individual requirements, and concussion management practices are reported with descriptives. Regression was used to identify specific predictors of both overall and individual settlement requirements. An ANOVA compared compliance by NCAA division level. Being pressured to be non-compliant was assessed between sexes by a chi-square. There were 223 respondents (21.8%), and overall compliance was high (4.1 ± 0.7) with the five required Arrington Settlement components. Settlement requirement 1, pre-season baseline testing, and requirement 5, presence of trained personnel at all contact sport practices, had the lowest compliance rates at 44.8% and 73.3%, respectively. The number of sports the institution offered was the only significant predictor of each requirement. There was no difference in compliance between NCAA divisions. Although the overall rate of being non-compliant pressure was low (13.8%), females were 3.28x more likely report being pressured than males. NCAA institutions are generally compliant with the Arrington settlement; however, lack of clarity in the requirements, particularly requirement 1, raises potential concerns. Concussion management practices continue to incorporate multifaceted approaches and are largely consistent with current best practices.

Comparison of Various Metrics of Repetitive Head Impact Exposure And Their Associations With Neurocognition in Collegiate-Aged Athletes

OBJECTIVE

Characterize the levels of various metrics of repetitive head impacts (RHI) in contact (CS) and non-contact (NCS) sport athletes and determine the extent to which they are associated with fluid cognition.

METHODS

Collegiate-aged athletes (n = 176) completed semi-structured interviews about participation in contact sport. RHI was operationalized based on current sport (CS/NCS), the cumulative number of years of participation, age at first exposure (AFE), and based on recently proposed traumatic encephalopathy syndrome (TES) categories. The NIH Toolbox Cognition Battery assessed fluid cognition. General linear models compared RHI metrics between CS and NCS athletes and tested associations of RHI measures with fluid cognition.

RESULTS

CS athletes had more years of RHI exposure, higher rates of "extensive" exposure based on TES criteria, and were more likely to have AFE before age 12 relative to NCS (ps < .001). A subset of NCS athletes, however, reported prior RHI at levels categorized as being "extensive" based on TES criteria (5%), while a larger minority had AFE before 12 (34%). No adverse associations of RHI and fluid cognition were observed (ps > .05). Across all RHI metrics, more or earlier RHI was associated with better episodic memory (ps ≤ .05). Secondary analyses showed this effect was driven by women.

CONCLUSIONS

Current results find no evidence that RHI in collegiate-aged athletes is associated with worse neurocognition. Although there was extensive overlap among RHI measures, results demonstrate that categorizing athletes based on their current sport undercounts the lifetime RHI exposure in many NCS athletes.

Risk of Upper Extremity Musculoskeletal Injury Within the First Year After a Concussion

Background

Emerging evidence suggests that athletes and military personnel are at increased risk for lower extremity musculoskeletal injury after a concussion; however, the association between concussion and subsequent upper extremity (UE) musculoskeletal injury is unknown.

Purpose

To prospectively examine the association between concussion and UE musculoskeletal injury risk within the first year after returning to unrestricted activity.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 316 cases of concussion 42% (132/316 women) were observed among 5660 Concussion Assessment, Research and Education Consortium participants at the United States Military Academy from May 2015 to June 2018. Active injury surveillance within the cohort was conducted for 12 months after unrestricted return to activity to identify any incident cases of acute UE musculoskeletal injury. Injury surveillance during the follow-up period was also conducted for nonconcussed controls who were matched by sex and competitive sport level. Univariate and multivariable Cox proportional hazards regression models were used to estimate hazard ratios between concussed cases and nonconcussed controls for time to UE musculoskeletal injury.

Results

During the surveillance period, 19.3% of concussed cases and 9.2% of nonconcussed controls sustained a UE injury. In the univariate model, concussed cases were 2.25 times (95% CI, 1.45-3.51) more likely to sustain a UE injury during the 12-month follow-up period when compared with the nonconcussed controls. In the multivariable model, adjusted for history of concussion, sport level, somatization, and history of UE injury, concussed cases were 1.84 times (95% CI, 1.10-3.07) more likely to sustain a UE injury during the surveillance period compared with nonconcussed controls. Sport level remained an independent risk factor for UE musculoskeletal injury; however, concussion history, somatization, and history of UE injury were not independent risk factors.

Conclusion

Concussed cases were more than twice as likely to sustain an acute UE musculoskeletal injury within the first 12 months after unrestricted return to activity when compared with nonconcussed controls. The higher hazard of injury remained in the concussed group after adjusting for other potential risk factors.

Primary and Secondary Risk Factors Associated With Concussion Symptom Clusters in Collegiate Athletes: Results From the NCAA-DoD Grand Alliance CARE Consortium

Background

There is a broad and diverse range of symptoms after a concussion, from irritability to nausea. This heterogeneity of symptoms is a challenge for clinicians managing the different presentations among injuries. Prior research has investigated the structure of postconcussive symptoms to determine if they can be grouped into clusters of related symptoms.

Purpose/Hypothesis

The purpose of this study was to identify symptom clusters during the acute phase after a sports-related concussion using exploratory factor analysis and to understand the relationship between risk factors for postconcussion symptoms (ie, demographics, injury characteristics, mental health, and sleep qualities) and different symptom clusters. We hypothesized that certain factors would be predictive of specific symptom clusters.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Collegiate athletes (N = 1104) from the Concussion, Assessment, Research, and Education (CARE) Consortium completed the Sport Concussion Assessment Tool-Third Edition symptom assessment tool 24 to 48 hours after concussion. Exploratory factor analysis was conducted on the symptom evaluation to determine symptom clusters 24 to 48 hours after concussion. Regression analysis was used to examine the effects of pre- and postinjury characteristics.

Results

Exploratory factor analysis revealed a 4-cluster structure for acute postconcussive symptoms that explained 62% of the variance in symptom reporting: vestibular-cognitive, migrainous, cognitive fatigue, and affective. Delayed reporting, less sleep before assessment, female sex, and being hurt outside of competition (during practice/training) was correlated with increased symptoms for 4 symptom clusters. Depression predicted higher vestibular-cognitive and affective symptoms. Amnesia was correlated with higher vestibular-cognitive and migrainous symptoms, whereas migraine history was associated with more migrainous and affective symptoms.

Conclusion

Symptoms can be grouped into 1 of 4 distinct clusters. Certain variables were associated with increased symptoms across multiple clusters and may be indicative of greater injury severity. Other factors (ie, migraine history, depression, amnesia) were associated with a more specific symptom presentation and may be mechanistically related to concussion outcomes and biological markers.

Computerized and functional reaction time in varsity-level female collegiate athletes with and without a concussion history

OBJECTIVES

To 1) determine the association between computerized and functional reaction time, and 2) compare functional reaction times between female athletes with and without a concussion history.

DESIGN

Cross-sectional study.

METHODS

Twenty female college athletes with concussion history (age = 19.1 ± 1.5 years, height = 166.9 ± 6.7 cm, mass = 62.8 ± 6.9 kg, median total concussion = 1.0 [interquartile range = 1.0, 2.0]), and 28 female college athletes without concussion history (age = 19.1 ± 1.0 years, height = 172.7 ± 8.3 cm, mass = 65.4 ± 8.4 kg). Functional reaction time was assessed during jump landing and dominant and non-dominant limb cutting. Computerized assessments included simple, complex, Stroop, and composite reaction times. Partial correlations investigated the associations between functional and computerized reaction time assessments while covarying for time between computerized and functional reaction time assessments. Analysis of covariance compared functional and computerized reaction time, covarying for time since concussion.

RESULTS

There were no significant correlations between functional and computerized reaction time assessments (p-range = 0.318 to 0.999, partial correlation range = -0.149 to 0.072). Reaction time did not differ between groups during any functional (p-range = 0.057 to 0.920) or computerized (p-range = 0.605 to 0.860) reaction time assessments.

CONCLUSIONS

Post-concussion reaction time is commonly assessed via computerized measures, but our data suggest computerized reaction time assessments are not characterizing reaction time during sport-like movements in varsity-level female athletes. Future research should investigate confounding factors of functional reaction time.

Sensitivity and Specificity of the ImPACT Neurocognitive Test in Collegiate Athletes and US Military Service Academy Cadets with ADHD and/or LD: Findings from the NCAA-DoD CARE Consortium

BACKGROUND AND OBJECTIVE

Computer-based neurocognitive tests are widely used in sport-related concussion management, but the performance of these tests is not well understood in the participant population with attention-deficit/hyperactivity disorder (ADHD) and/or learning disorder (LD). This research estimates the sensitivity and specificity performance of the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) computer-based neurocognitive test in identifying concussion in this population.

METHODS

Study participants consisted of collegiate university athletes and military service academy cadets from the National Collegiate Athletic Association-Department of Defense CARE Consortium who completed the ImPACT test between 2014 and 2021. Participants who self-identified as belonging to one of the subgroups of interest (ADHD with or without LD [ADHD:LD+/-], LD with or without ADHD [LD:ADHD+/-], ADHD and/or LD [ADHD a/o LD]) and completed a baseline (1874 ADHD:LD+/-, 779 LD:ADHD+/-, 2338 ADHD a/o LD) or 24-48 h post-concussion (175 ADHD:LD+/-, 77 LD:ADHD+/-, 216 ADHD a/o LD) ImPACT assessment were included. Sensitivity and specificity were calculated using a normative data method and three machine learning classification methods: logistic regression, classification and regression tree, and random forest.

RESULTS

Using the four methods, participants with ADHD:LD+/- had sensitivities that ranged from 0.474 to 0.697, and specificities that ranged from 0.538 to 0.686. Participants with LD:ADHD+/- had sensitivities that ranged from 0.455 to 0.688, and specificities that ranged from 0.456 to 0.588. For participants with ADHD a/o LD, sensitivities ranged from 0.542 to 0.755, and specificities ranged from 0.451 to 0.724.

CONCLUSIONS

For all subgroups and analytical methods, the results illustrate sensitivity and specificity values below typically accepted levels indicative of clinical utility. These findings support that using ImPACT alone may be insufficient to inform concussion diagnoses and encourages the use of a multi-dimensional concussion assessment.

Test-Retest Reliability and Efficacy of Individual Symptoms in Concussion Management

OBJECTIVE

(1) To determine test-retest reliability of individual Sport Concussion Assessment Tool-Third Edition (SCAT-3) symptom scores and symptom severity scores, (2) to examine the specificity/sensitivity of individual SCAT-3 symptom severity scores acutely (24-48 hours) postconcussion, and (3) to develop a model of symptoms best able to differentiate concussed from nonconcussed student athletes and cadets.

DESIGN

Prospective, longitudinal, and cross-sectional.

SETTING

Twenty-six civilian schools and 3 US service academies.

PARTICIPANTS

Collegiate student athletes (n = 5519) and cadets (n = 5359) from the National Collegiate Athletic Association-Department of Defense Grand Alliance: Concussion Assessment, Research and Education Consortium, including 290 student athletes and 205 cadets, assessed 24 to 48 hours postconcussion.

INDEPENDENT VARIABLES

Concussed and nonconcussed student athlete and cadet groups.

MAIN OUTCOME MEASURES

Sport Concussion Assessment Tool-Third Edition individual symptom severity scores, total symptom scores, and symptom severity scores.

RESULTS

Results indicated poor test-retest reliability across all symptom scores (intraclass correlation coefficient = 0.029-0.331), but several individual symptoms had excellent predictive capability in discriminating concussed from nonconcussed participants (eg, headache, pressure in the head, and don't feel right had area under the curve >0.8, sensitivity >70%, and specificity >85%) regardless of baseline testing. These symptoms were consistent with Chi-square Automatic Interaction Detector classification trees with the highest mean probability.

CONCLUSIONS

Findings support the excellent diagnostic accuracy of honest symptom reporting, notwithstanding the known limitations in symptom underreporting, and suggest that there may be added value in examining individual symptoms rather than total symptom scores and symptom severity scores alone. Finally, findings suggest that baseline testing is not necessary for interpreting postconcussion symptom scores.

One-year stability of preseason Sport Concussion Assessment Tool 5 (SCAT5) values in university level collision and combative sport athletes

OBJECTIVES

To determine the stability of the Sport Concussion Assessment Tool (SCAT) 5 between consecutive seasons in uninjured collision and combative varsity athletes.

METHODS

Thirty-six athletes (19 females) were recruited to participate (wrestling [n = 12], rugby [n = 14], and hockey [n = 10]). The SCAT5 was administration at the start of the 2017 and 2018 seasons. Median baseline demographics for 2017 were as follows: age (19 years [range: 17-24 years]), height (174 cm [range: 149-195 cm]), and weight (76 kg [range: 57-118 kg]). Outcome metrics included subcomponents of the SCAT5: symptom reporting, standardized assessment of concussion (SAC), neurological screening, and balance performance measured with the modified balance error scoring system (mBESS). Wilcoxon signed-rank tests and Cronbach's alpha (α) values were calculated to determine the stability between consecutive years for the SCAT5 variables in the same cohort of athletes. Bonferroni corrections were applied for Wilcoxon signed-rank tests, where alpha = 0.006 (0.05/9).

RESULTS

Between the 2017 and 2018 seasons, no differences were noted in symptom reporting (p = 0.14), SAC (p = 0.32), neurological screening (p = 0.98), and balance performance on the mBESS (p = 0.01). The Cronbach's alpha displayed unacceptable to questionable levels of within-subject stability (range: α = 0.34-0.70) for all subcomponents, except months in reverse order (α = 0.92).

CONCLUSIONS

While no statistical differences were present for all SCAT5 subcomponent metrics between 2017 and 2018 baselines, all but one displayed unacceptable to questionable stability (α ≤ 0.70) when retested one year later. Further research is needed to understand the appropriate time duration baseline SCAT5 values can reliably be utilized within longitudinal studies; as well as the normal variation of SCAT5 reporting/scoring.

Optimizing Concussion Care Seeking: The Influence of Previous Concussion Diagnosis Status on Baseline Assessment Outcomes

BACKGROUND

The prevalence of unreported concussions is high, and undiagnosed concussions can lead to worse postconcussion outcomes. It is not clear how those with a history of undiagnosed concussion perform on subsequent standard concussion baseline assessments.

PURPOSE

To determine if previous concussion diagnosis status was associated with outcomes on the standard baseline concussion assessment battery.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Concussion Assessment, Research, and Education (CARE) Consortium participants (N = 29,934) self-reported concussion history with diagnosis status and completed standard baseline concussion assessments, including assessments for symptoms, mental status, balance, and neurocognition. Multiple linear regression models were used to estimate mean differences and 95% CIs among concussion history groups (no concussion history [n = 23,037; 77.0%], all previous concussions diagnosed [n = 5315; 17.8%], ≥1 previous concussions undiagnosed [n = 1582; 5.3%]) at baseline for all outcomes except symptom severity and Brief Symptom Inventory-18 (BSI-18) score, in which negative binomial models were used to calculate incidence rate ratios (IRRs). All models were adjusted for sex, race, ethnicity, sport contact level, and concussion count. Mean differences with 95% CIs excluding 0.00 and at least a small effect size (≥0.20), and those IRRs with 95% CIs excluding 1.00 and at least a small association (IRR, ≥1.10) were considered significant.

RESULTS

The ≥1 previous concussions undiagnosed group reported significantly greater symptom severity scores (IRR, ≥1.38) and BSI-18 (IRR, ≥1.31) scores relative to the no concussion history and all previous concussions diagnosed groups. The ≥1 previous concussions undiagnosed group performed significantly worse on 6 neurocognitive assessments while performing better on only 2 compared with the no concussion history and all previous concussions diagnosed groups. There were no between-group differences on mental status or balance assessments.

CONCLUSION

An undiagnosed concussion history was associated with worse clinical indicators at future baseline assessments. Individuals reporting ≥1 previous undiagnosed concussions exhibited worse baseline clinical indicators. This may suggest that concussion-related harm may be exacerbated when injuries are not diagnosed.

Heterogeneity in Blood Biomarker Trajectories After Mild TBI Revealed by Unsupervised Learning

Concussions, also known as mild traumatic brain injury (mTBI), are a growing health challenge. Approximately four million concussions are diagnosed annually in the United States. Concussion is a heterogeneous disorder in causation, symptoms, and outcome making precision medicine approaches to this disorder important. Persistent disabling symptoms sometimes delay recovery in a difficult to predict subset of mTBI patients. Despite abundant data, clinicians need better tools to assess and predict recovery. Data-driven decision support holds promise for accurate clinical prediction tools for mTBI due to its ability to identify hidden correlations in complex datasets. We apply a Locality-Sensitive Hashing model enhanced by varied statistical methods to cluster blood biomarker level trajectories acquired over multiple time points. Additional features derived from demographics, injury context, neurocognitive assessment, and postural stability assessment are extracted using an autoencoder to augment the model. The data, obtained from FITBIR, consisted of 301 concussed subjects (athletes and cadets). Clustering identified 11 different biomarker trajectories. Two of the trajectories (rising GFAP and rising NF-L) were associated with a greater risk of loss of consciousness or post-traumatic amnesia at onset. The ability to cluster blood biomarker trajectories enhances the possibilities for precision medicine approaches to mTBI.

Effects of Pre-Collegiate Sport Specialization on Cognitive, Postural, and Psychological Functions: Findings from the NCAA-DoD CARE Consortium

Background: Early sport specialization has been associated with an increased risk of musculoskeletal injuries and unfavorable psychological outcomes; however, it is unknown whether sport specialization is associated with worse cognitive, postural, and psychological functions in first-year collegiate student-athletes. Methods: First-year collegiate multisport (MA) and single-sport (SA) student-athletes were identified using a pre-collegiate sport experience questionnaire. The cognitive, postural, and psychological functions were assessed by the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT), Standardized Assessment of Concussion (SAC), Balance Error Scoring System (BESS), and Brief Symptom Inventory 18 (BSI-18). Results: MA student-athletes performed higher in cognitive outcomes (e.g., higher ImPACT visual memory composite scores [ß = 0.056, p < 0.001]), but had higher psychological distress (e.g., higher BSI-18 global severity index [ß = 0.057, p < 0.001]) and no difference in postural stability (p > 0.05) than SA student-athletes. Conclusions: This study indicated first-year collegiate athletes with a history of sport specialization demonstrate lower cognitive performance but decreased psychological distress and no differences in static postural stability as compared to their MA counterparts. Future studies should consider involving different health measures to better understand the influence of sport specialization on overall physical and mental health.

In-Season Concussion Symptom Reporting in Male and Female Collegiate Rugby Athletes

Symptom inventories are generally only collected after a suspected concussion, but regular in-season monitoring may allude to clinical symptoms associated with repetitive subconcussive impacts and potential undiagnosed concussions. Despite sex-specific differences in symptom presentation and outcome of concussion, no return-to-play protocol takes sex into account. The objective of this study was to monitor a cohort of contact-sport athletes and compare the frequency and severity of in-season concussion-like symptom reporting between sexes. Graded symptom checklists from 144 female and 104 male athlete-seasons were administered weekly to quantify the effect of subconcussive impacts on frequency and severity of in-season symptom reporting. In-season, mean symptom severity score (SSS) (p = 0.026, mean difference of 1.8), mean number of symptoms (p = 0.044, mean difference of 0.9), max SSS (p < 0.001, mean difference of 19.2), and max number of symptoms (p < 0.001, mean difference of 6.8) were higher in the females. The females' survey results showed differences between elevated and concussed SSS (p < 0.005, mean difference of 28.1) and number of symptoms reported (p = 0.001, mean difference of 6.6). The males did not have a difference in SSS (p = 0.97, mean difference of 1.12) nor in number of symptoms (p = 0.35, mean difference of 1.96) from elevated to concussed athletes. Rugby players report concussion-like symptoms in the absence of a diagnosed concussion in-season. Female athletes reported elevated symptom frequencies with greater severities than the males, but both sexes reported considerable levels throughout the season.

Paired cognitive flexibility task with symptom factors improves detection of sports-related concussion in high school and collegiate athletes

Determining the sensitivity and specificity of short neurocognitive assessments to objectively detect concussion will help clinicians more confidently integrate such tools in clinical management decisions. This study quantified the sensitivity and specificity of a computerized cognitive flexibility task isolating shifts of visuospatial attention in combination with clinical symptoms acutely (< 72 h) following concussion. A total of 100 athletes (53 concussed; 47 non-injured control; 42% female) completed computerized neurocognitive testing and clinical symptom reports (Sport Concussion Assessment Tool 3rd edition: SCAT3). Separate discriminant function analyses were performed for individual, combination, and stepwise inclusion of neurocognitive and clinical symptomology assessments. Findings revealed the combination of neurocognitive outcomes (i.e., mean reaction time, response accuracy, and response accuracy cost) with clinical symptom factor scores exhibited the greatest sensitivity (95.7%) and specificity (88.7%) as well as the highest positive predictive value (95.9%) and negative predictive value (88%) relative to other approaches. Further, a stepwise approach predicting concussion status using the discriminant functions improved detection of concussion (98.2% sensitivity, 95.7% specificity, 96.4% positive predictive value, and 97.8% negative predictive value) when clinical symptom factors failed to indicate the presence of a concussion. Incorporating a cognitive flexibility task involving shifts of visuospatial attention combined with clinical symptom factor scores may improve clinical decision-making as this approach exceeds the sensitivity and specificity of widely popular neurocognitive test batteries and takes less than 10 min to administer.

Sport Concussion Assessment Tool-5th Edition (SCAT5): Normative Reference Values for the National Rugby League Women's Premiership

Objective: To establish normative reference values for the Sport Concussion Assessment Tool-5th Edition (SCAT5) for the new National Rugby League Women's Premiership. Methods: Preseason SCAT5 baseline testing was administered individually to all National Rugby League Women's Premiership players (N = 117). Testing was completed by the medical staff. Normative reference values were calculated for the components of the SCAT5, including the Standardized Assessment of Concussion, modified Balance Error Scoring System, and the Symptom Scale. A small case series of players who sustained concussions were included to illustrate the use of the new normative data. Results: The median Standardized Assessment of Concussion total score was 27.0 (M = 26.9, SD = 2.1). The median modified Balance Error Scoring System score was 2.0 (M = 2.4, SD = 2.2). The median number of symptoms score was 1.0 (M = 3.2, SD = 4.7) and the median symptom severity score was 2.0 (M = 5.4, SD = 8.2). The most common baseline symptom was fatigue or low energy (33%), followed by trouble sleeping (24%), headache (23%), neck pain (22%), and difficulty remembering (21%). In the total sample, 41% reported no symptoms. The clinical interpretation of these new normative data to a case series of women with concussions is provided. Conclusions: Normative reference values are provided for the SCAT5 for women who are professional rugby league players. Using these normative data will improve clinical interpretation of SCAT5 scores following a concussion.

Association of Previous Concussion with Hippocampal Volume and Symptoms in Collegiate-Aged Athletes

There is concern that previous concussion and contact-sport exposure may have negative effects on brain structure and function. Accurately quantifying previous concussion is complicated by the fact that multiple definitions exist, with recent definitions allowing for diagnosis based on the presence of symptoms alone (Concussion in Sport Group criteria; CISG) rather than the presence of acute injury characteristics such as alterations in mental status (American Congress of Rehabilitation Medicine criteria; ACRM). The goals of the current work were to determine the effects of previous concussion and contact-sport exposure on gray matter structure and clinical measures in healthy, young-adult athletes and determine the extent to which these associations are influenced by diagnostic criteria used to retrospectively quantify concussions. One-hundred eight collegiate-aged athletes were enrolled; 106 athletes were included in final analyses (age, 21.37 ± 1.69; 33 female). Participants completed a clinical battery of self-report and neurocognitive measures and magnetic resonance imaging to quantify subcortical volumes and cortical thickness. Semistructured interviews were conducted to measure exposure to contact sports and the number of previous concussions based on CISG and ACRM criteria. There was a significant association of concussion-related and psychological symptoms with previous concussions based on ACRM (ps < 0.05), but not CISG, criteria. Hippocampal volume was inversely associated with the number of previous concussions for both criteria (ps < 0.05). Findings provide evidence that previous concussions are associated with smaller hippocampal volumes and greater subjective clinical symptoms in otherwise healthy athletes and highlight the importance of diagnostic criteria used to quantify previous concussion.

The relation between neck strength and psychological distress: preliminary evidence from collegiate soccer athletes

AIM

To examine whether neck strength and symmetry are associated with psychological function in athletes with exposure to repetitive head impacts.

METHODS

Collegiate soccer (n = 29) and limited/noncontact (n = 63) athletes without a history of concussion completed the Brief Symptom Inventory 18 and assessments of isometric neck strength. Neck strength symmetry was calculated as the difference in strength between opposing muscle groups.

RESULTS

The results demonstrated that lower neck strength was associated with more symptoms of anxiety, whereas asymmetry in neck strength was associated with more symptoms of somatization and depression in soccer athletes only.

CONCLUSION

These preliminary results suggest that greater neck strength/symmetry is related to better psychological function in athletes who have higher exposure to repetitive head impacts.

Assessing Differences in Concussion Symptom Knowledge and Sources of Information Among Black and White Collegiate-Athletes

OBJECTIVE

Basic concussion symptom knowledge is fundamental to concussion identification; however, racial disparities in concussion knowledge exist in high school and youth sports. It is unknown whether similar differences exist in collegiate-athletes. Identifying racial disparities in concussion knowledge and sources of concussion information is essential to inform equitable approaches to knowledge translation and educational interventions. This study examined how Black and White collegiate-athletes differed in their knowledge of concussion symptoms and use of concussion information sources.

SETTING

National Collegiate Athletic Association (NCAA) institutions.

PARTICIPANTS

Collegiate-athletes.

DESIGN

Cross-sectional.

MAIN MEASURES

Collegiate-athletes completed a questionnaire that assessed personal and sports demographics, concussion symptom knowledge, and use of concussion information sources. Fisher's exact tests and Wilcoxon rank-sum tests examined differences in outcome measures between Black and White collegiate-athletes. A multivariable Poisson regression model examined the association between race and concussion symptom knowledge scores while accounting for sex, sports contact level, NCAA division, concussion history, and specific concussion information sources. Incidence rate ratios (IRRs) with 95% CIs excluding 1.00 were deemed significant.

RESULTS

A total of 768 (82.6% White, 17.4% Black) collegiate-athletes completed the questionnaire. Black athletes were more likely to have lower concussion symptom knowledge scores than White athletes (P < .001). In the multivariable Poisson regression model controlling for covariates, this finding was retained (IRR = 0.97; 95% CI, 0.94-0.997). White athletes were more likely to report school-based professional (P < .001), online medical sources (P = .02), and the NCAA (P = .008) as sources of concussion information. Black athletes were more likely to report referees (P = .03) as a source of concussion knowledge.

CONCLUSION

Despite NCAA concussion education requirements for athletes, Black collegiate-athletes were found to have lower concussion knowledge than White collegiate-athletes. The findings highlight the need for equitable strategies to disseminate concussion information to diverse populations by improving the physician-patient relationship and investing in culturally appropriate educational materials.

Novice vs expert inter-rater reliability of the balance error scoring system in children between the ages of 5 and 14

BACKGROUND

The Balance Error Scoring System (BESS) is a tool to measure balance, however, no studies have shown its reliability between novice and expert raters.

RESEARCH QUESTION

What is the inter-rater reliability of BESS measurements when performed by novice raters compared to experts, and does completion of a focused, online training module increase the inter-rater reliability among novice raters?

METHODS

In this reliability study, 5 novice volunteers were asked to independently rate BESS tests from 50 random prerecorded BESS videos of normal healthy subjects aged 5-14. Novice raters regraded the same 50 videos after receiving a formal training. The novices' scores before and after the formal training were compared to one another and then the scores were compared to 4 expert scores. Intraclass correlation (ICC) with 95 % confidence intervals or percent agreements were calculated and compared across groups.

RESULTS

For the total BESS score, novice raters showed good reliability (ICC 0.845) which did not change with a formal training (ICC 0.846). Expert raters showed excellent reliability (ICC 0.929). Poor to moderate reliability was noted in the foam stance-single leg in the untrained novice and trained novice group (ICCs 0.452 and 0.64 L respectively).

SIGNIFICANCE

BESS testing by novice raters with only written instruction and no formal training yields good inter-rater reliability. In contrast, BESS testing by expert raters yields excellent reliability. A focused training for novice raters conferred a small improvement in the reliability of the scoring of the single leg stance on foam condition but not a significant difference to the overall BESS score. While novices demonstrated promising reliability for overall BESS scores, optimizing clinical research using the BESS with expert raters show the highest reliability.

Sport Contact Level Affects Post-Concussion Neurocognitive Performance in Young Athletes

OBJECTIVE

Contact level affects the incidence of sports-related concussion. However, the effects of contact level on injury severity and recovery are less clear and are the focus of this study.

METHOD

Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) for athletes aged 12-22 was performed at baseline (n = 10,907 for 7,058 athletes), after suspected concussion determined by physicians or athletic trainers (n = 5,062 for 4,419 athletes), and during follow-up visits (n = 3,264 for 2,098 athletes). Athletes played contact/collision (CC), limited contact (LC), and noncontact (NC) sports. Injury incidence, severity, and recovery were measured using raw and change from baseline neurocognitive test scores. Comparisons between groups used univariate analysis and multivariable regression controlling for demographic variables.

RESULTS

Compared to CC athletes, LC and NC athletes showed decreased suspected concussion incidence. At initial post-injury testing, all neurocognitive test scores were similar between groups except changes from baseline for processing speed were improved for LC compared to CC athletes. Upon follow-up testing, raw neurocognitive scores were better for NC compared to the contact collision athletes in verbal memory, processing speed, total symptom score, migraine cluster, cognitive cluster, and neuropsychiatric cluster scores. For change from baseline scores, LC athletes exhibited better performance on verbal memory, processing speed, and reaction time but also showed higher neuropsychiatric scores than CC athletes.

CONCLUSION

Neurocognitive scores between contact levels were similar at the first post-injury test. However, follow up showed many improved scores and symptoms for limited and NC sports compared to CC sports, which may indicate faster recovery.

A Normative Reference vs. Baseline Testing Compromise for ImPACT: The CARE Consortium Multiple Variable Prediction (CARE-MVP) Norms

BACKGROUND

Sports medicine clinicians routinely use computerized neurocognitive testing in sport-related concussion management programs. Debates continue regarding the appropriateness of normative reference comparisons versus obtaining individual baseline assessments, particularly for populations with greater likelihood of having below- or above-average cognitive abilities. Improving normative reference methods could offer alternatives to perceived logistical and financial burdens imposed by universal baseline testing.

OBJECTIVES

To develop and validate the Concussion Assessment, Research, and Education (CARE) Consortium Multiple Variable Prediction (MVP) norms for the Immediate Postconcussion Assessment and Cognitive Testing (ImPACT).

METHODS

We developed the CARE-MVP norms for ImPACT composite scores using regression-based equations. Predictor variables included sex, race (white/Caucasian, black/African American, Asian, or Multiple Races), medical history [attention-deficit/hyperactivity disorder (ADHD), learning disorder (LD), prior concussion(s), prior psychiatric diagnosis], and an estimate of premorbid intellect (Wechsler Test of Adult Reading). CARE-MVP norms were first validated in an independent sample of healthy collegiate athletes by comparing predicted and actual baseline test scores using independent-samples t-tests and Cohen's d effect sizes. We then evaluated base rates of low scores in athletes self-reporting ADHD/LD (vs. non-ADHD/LD) and black/African American race (vs. white/Caucasian) across multiple normative reference methods (Chi square, Cramer's V effect size). Lastly, we validated the CARE-MVP norms in a concussed sample (dependent samples t test, Cohen's d effect size).

RESULTS

A total of 5233 collegiate athletes (18.8 ± 1.2 years, 70.5% white/Caucasian, 39.1% female) contributed to the CARE-MVP norms (development N = 2616; internal validation N = 2617). Race and WTAR score were the strongest and most consistent ImPACT score predictors. There were negligible mean differences between observed and predicted (CARE-MVP) baseline scores (Cohen's d < 0.1) for all ImPACT composite scores except Reaction Time (predicted ~ 20 ms faster than observed, d = - 0.28). Low score base rates were similar for athletes across subpopulations when using CARE-MVP norms (ADHD/LD, V = 0.017-0.028; black/African American, V = 0.043-0.053); while, other normative reference methods resulted in disproportionately higher rates of low scores (ADHD/LD, V = 0.062-0.101; black/African American race, V = 0.163-0.221). Acute (24-48 h) postconcussion ImPACT scores were significantly worse than CARE-MVP norms but notably varied as a function of concussion symptom severity.

CONCLUSIONS

Results support CARE-MVP norm use in populations typically underrepresented or not adjusted for in traditional normative reference samples, such as those self-reporting ADHD/LD or black/African American race. CARE-MVP norms improve upon prior normative methods and may offer a practical, simple alternative for collegiate institutions concerned about logistical and financial burden associated with baseline testing. An automated scoring program is provided.

Examining Whether Onfield Motor Incoordination Is Associated With Worse Performance on the SCAT5 and Slower Clinical Recovery Following Concussion

Objective: To examine the relationship between video-identified onfield motor incoordination, the acute assessment of concussion, and recovery time during three seasons of National Rugby League (NRL) play. Methods: Blows to the head ("head impact events") were recorded by sideline video operators and medical staff. Any player with a suspected concussion underwent a Head Injury Assessment in which he was taken off the field and medically evaluated, including the administration of the Sports Concussion Assessment Tool, 5th Edition (SCAT5). Video footage was later examined to determine the presence or absence of onfield motor incoordination following the head impact event. Results: Motor incoordination was identified in 100/1,706 head impact events (5.9%); 65 of the 100 instances of motor incoordination (65.0%) were ultimately medically diagnosed with a concussion. In 646 athletes for whom SCAT5 data were available, those with motor incoordination were more likely to report both dizziness and balance problems than those without motor incoordination, but there were no group differences on an objective balance test. Additionally, there was no relationship between presence/absence of motor incoordination and number of games missed or time to medical clearance for match play. Conclusion: In NRL players, motor incoordination is a readily observable onfield sign that is strongly associated with a medical diagnosis of concussion and with self-reported dizziness/balance problems. However, onfield motor incoordination is not associated with objective balance performance and it is not predictive of time to recover following concussion.

Estimated Age of First Exposure to Contact Sports and Neurocognitive, Psychological, and Physical Outcomes in Healthy NCAA Collegiate Athletes: A Cohort Study

BACKGROUND

Collegiate football players who started playing tackle football before age 12 years did not show worse neuropsychological test performance than those who started playing tackle football after age 12 years. It is unknown if beginning other contact sports, such as lacrosse, at a younger age is associated with worse neurocognitive performance, greater psychological distress, or worse postural stability in collegiate student athletes.

OBJECTIVE

The purpose of this study was to examine the association between estimated age of first exposure (eAFE) to repetitive head impacts (RHI) and these outcome measures in collegiate student athletes.

METHODS

1891 female and 4448 male collision/contact (i.e., football, ice hockey, lacrosse, wrestling, soccer) and non-contact (i.e., golf, rifle, rowing/crew, swimming, tennis) sport athletes completed baseline testing, including the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT), Brief Symptom Inventory 18 (BSI-18), and Balance Error Scoring System (BESS).

RESULTS

For women, the eAFE-by-sport interaction was associated with ImPACT Verbal Memory and Visual Memory, whereby earlier eAFE to contact sports was associated with higher composite scores (B = - 0.397, B = - 0.485, respectively). For men, the eAFE-by-sport interaction was associated with BSI-18 Depression and Global Severity Index and symptom severity scores, whereby earlier eAFE to football was associated with lower psychological distress and symptom severity [Depression, Exp(B) = 1.057; Global Severity Index, Exp(B) = 1.047; Symptom Severity, Exp(B) = 1.046]. Parameter estimates were small suggesting these results may have minimal practical relevance.

CONCLUSION

Findings suggest that RHI during early adolescence is unrelated to brain health as measured by these specific outcome measures in collegiate student athletes.

Baseline preseason ImPACT® testing in Mandarin with adolescent student-athletes in the United States

Researchers have examined differences on ImPACT^® in baseline symptom reporting and neurocognitive performances based on the language of administration and racial/ethnic identity. This is the first study to examine differences between student-athletes tested in Mandarin versus English on ImPACT^® during preseason baseline assessments conducted in high schools in the United States. Participants included 252 adolescent student-athletes who completed ImPACT^® testing in the state of Maine in Mandarin and 252 participants who completed testing in English, matched on age, gender, and health and academic history. Participants were compared on neurocognitive composite scores and symptom ratings. Boys tested in Mandarin, but not girls, had modestly better neurocognitive performance on one of four composite scores (i.e., Visual Motor Speed, p < .001, d = .45). Although language groups did not differ in total symptom severity, boys tested in Mandarin endorsed multiple physical symptoms at higher rates than boys tested in English. These results suggest that the current ImPACT^® neurocognitive normative data are reasonably appropriate for use with adolescents evaluated in Mandarin. There were some differences in the reporting of physical symptoms, with greater rates of symptom endorsement by boys tested in Mandarin than boys tested in English; but overall symptom severity ratings were comparable between the language groups.

Impairments in Dynamic Postural Control across Concussion Clinical Milestones

The aim of this study was to assess gait initiation (GI) performance longitudinally across clinical concussion recovery milestones through return to participation (RTP). We recruited 54 collegiate student-athletes, 27 with concussions and 27 matched controls (15 female and 12 male per group). Participants performed five trials of GI at baseline and again at five post-concussion clinical milestones: 1) Acute, the day clinical tests achieved baseline values on the 2) Balance Error Scoring System (BESS), 3) Immediate Post-Concussion Assessment and Cognitive Test ImPACT, 4) Asymptomatic, and 5) RTP Day. GI performance on six outcome measures (anterior/posterior and medial/lateral center of pressure displacements and velocities during the anticipatory postural adjustment [APA] phase and initial step length and velocity) with repeated-measures mixed model and pair-wise post hoc. A reliable change index (RCI) was calculated, and post-concussion participant's performance was compared to the RCI at milestones. There were significant interactions for APA posterior and lateral displacement, APA posterior velocity, step length, and step velocity. The post-hoc tests identified significant deficits across clinical milestones and at RTP for APA posterior and lateral displacement, step length, and step velocity. There were no post-hoc differences for any outcome measure in the control group. At RTP, 85.2-88.9% of concussion participants had at least one outcome measure which exceeded the 80% or 95% RCI. The primary finding of this study was persistent impairments in dynamic postural control, suggesting ongoing neurophysiological impairment despite clinical recovery. These results suggest that collegiate student-athletes may be RTP before neurophysiological recovery and potentially exposing themselves to elevated risk of recurrent concussion or subsequent musculoskeletal injury.

Differences in sport-related concussion for female and male athletes in comparable collegiate sports: a study from the NCAA-DoD Concussion Assessment, Research and Education (CARE) Consortium

OBJECTIVES

To examine sex differences in sport-related concussion (SRC) across comparable sports.

METHODS

Prospective cohort of collegiate athletes enrolled between 2014 and 2017 in the Concussion Assessment, Research and Education Consortium study.

RESULTS

Among 1071 concussions (females=615; 57.4%), there was no difference in recovery (median days to full return to play) (females=13.5 (IQR 9.0, 23.1) vs males=11.8 (IQR 8.1, 19.0), p=0.96). In subgroup analyses, female recovery was longer in contact (females=12.7 days (IQR 8.8, 21.4) vs males=11.0 days (IQR 7.9, 16.2), p=0.0021), while male recovery was longer in limited contact sports (males=16.9 days (IQR 9.7, 101.7) vs females=13.8 days (IQR 9.1, 22.0), p<0.0001). There was no overall difference in recovery among Division I schools (females=13.7 (IQR 9.0, 23.1) vs males=12.2 (IQR 8.2 19.7), p=0.5), but females had longer recovery at the Division II/III levels (females=13.0 (IQR 9.2, 22.7) vs males=10.6 (IQR 8.1, 13.9), p=0.0048).

CONCLUSION

Overall, no difference in recovery between sexes across comparable women's and men's sports in this collegiate cohort was found. However, females in contact and males in limited contact sports experienced longer recovery times, while females had longer recovery times at the Division II/III level. These disparate outcomes indicate that, while intrinsic biological sex differences in concussion recovery may exist, important, modifiable extrinsic factors may play a role in concussion outcomes.

Proposal of a Functional Impairment Symptom Scale for Concussion

Clinicians currently administer patient-reported symptom scales to quantify and track concussion symptoms. These scales are based on subjective ratings without reference to the degree of functional impairment caused by the symptoms. Our objective was to develop a concussion symptom scale based on functional impairment and compare it to a widely used concussion symptom checklist. We conducted a retrospective chart review evaluating 133 patients age 9-22 with an acute concussion who completed 2 symptom checklists at their initial visit-the Sport Concussion Assessment Tool (SCAT-3) symptom evaluation (22 symptoms, 0-6 scale) and the proposed Functional Impairment Scale (22 symptoms, 0-3 scale related to degree of functional impairment). Mean total symptom score was 27.2±22.9 for Sport Concussion Assessment Tool-3 and 14.7±11.9 for the Functional Impairment Scale. Pearson correlation between the scales was 0.98 (P < .001). Mean time from concussion to first visit was 6.9±6.2 days, and median clearance time after injury was 19 (95% CI 16-21) days. After adjusting for patient and injury characteristics, an increased score on each scale was associated with longer time to clearance (5-point increase in Sport Concussion Assessment Tool-3 hazard ratio 0.885, 95% CI 0.835-0.938, P < .001; 2.5-point increase in Functional Impairment Scale hazard ratio 0.851, 95% CI 0.802-0.902, P < .001). We propose a concussion symptom scale based on functional impairment that correlates strongly with the Sport Concussion Assessment Tool-3 scale, demonstrates a similar association with time to clearance, and may provide a more intuitive approach to monitoring how symptoms are affecting patients recovering from concussion. Future research should aim to validate this scale through a prospective longitudinal study.

Estimated age of first exposure to American football and outcome from concussion

OBJECTIVE

To examine the association between estimated age at first exposure (eAFE) to American football and clinical measures throughout recovery following concussion.

METHODS

Participants were recruited across 30 colleges and universities as part of the National Collegiate Athletic Association (NCAA)-Department of Defense Concussion Assessment, Research and Education Consortium. There were 294 NCAA American football players (age 19 ± 1 years) evaluated 24-48 hours following concussion with valid baseline data and 327 (age 19 ± 1 years) evaluated at the time they were asymptomatic with valid baseline data. Participants sustained a medically diagnosed concussion between baseline testing and postconcussion assessments. Outcome measures included the number of days until asymptomatic, Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) composite scores, Balance Error Scoring System (BESS) total score, and Brief Symptom Inventory 18 (BSI-18) subscores. The eAFE was defined as participant's age at the time of assessment minus self-reported number of years playing football.

RESULTS

In unadjusted regression models, younger eAFE was associated with lower (worse) ImPACT Visual Motor Speed (R 2 = 0.031, p = 0.012) at 24-48 hours following injury and lower (better) BSI-18 Somatization subscores (R 2 = 0.014, p = 0.038) when the athletes were asymptomatic. The effect sizes were very small. The eAFE was not associated with the number of days until asymptomatic, other ImPACT composite scores, BESS total score, or other BSI-18 subscores.

CONCLUSION

Earlier eAFE to American football was not associated with longer symptom recovery, worse balance, worse cognitive performance, or greater psychological distress following concussion. In these NCAA football players, longer duration of exposure to football during childhood and adolescence appears to be unrelated to clinical recovery following concussion.

Clinical Reaction-Time Performance Factors in Healthy Collegiate Athletes

CONTEXT

In the absence of baseline testing, normative data may be used to interpret postconcussion scores on the clinical reaction-time test (RTclin). However, to provide normative data, we must understand the performance factors associated with baseline testing.

OBJECTIVE

To explore performance factors associated with baseline RTclin from among candidate variables representing demographics, medical and concussion history, self-reported symptoms, sleep, and sport-related features.

DESIGN

Cross-sectional study.

SETTING

Clinical setting (eg, athletic training room).

PATIENTS OR OTHER PARTICIPANTS

A total of 2584 National Collegiate Athletic Association student-athletes (n = 1206 females [47%], 1377 males [53%], and 1 unreported (<0.1%); mass = 76.7 ± 18.7 kg; height = 176.7 ± 11.3 cm; age = 19.0 ± 1.3 years) from 3 institutions participated in this study as part of the Concussion Assessment, Research and Education Consortium.

MAIN OUTCOME MEASURE(S)

Potential performance factors were sex; race; ethnicity; dominant hand; sport type; number of prior concussions; presence of anxiety, learning disability, attention-deficit disorder or attention-deficit/hyperactivity disorder, depression, or migraine headache; self-reported sleep the night before the test; mass; height; age; total number of symptoms; and total symptom burden at baseline. The primary study outcome measure was mean baseline RTclin.

RESULTS

The overall RTclin was 202.0 ± 25.0 milliseconds. Female sex (parameter estimate [B] = 8.6 milliseconds, P < .001, Cohen d = 0.54 relative to male sex), black or African American race (B = 5.3 milliseconds, P = .001, Cohen d = 0.08 relative to white race), and limited-contact (B = 4.2 milliseconds, P < .001, Cohen d = 0.30 relative to contact) or noncontact (B = 5.9 milliseconds, P < .001, Cohen d = 0.38 relative to contact) sport participation were associated with slower RTclin. Being taller was associated with a faster RTclin, although this association was weak (B = -0.7 milliseconds, P < .001). No other predictors were significant. When adjustments are made for sex and sport type, the following normative data may be considered (mean ± standard deviation): female, noncontact (211.5 ± 25.8 milliseconds), limited contact (212.1 ± 24.3 milliseconds), contact (203.7 ± 21.5 milliseconds); male, noncontact (199.4 ± 26.7 milliseconds), limited contact (196.3 ± 23.9 milliseconds), contact (195.0 ± 23.8 milliseconds).

CONCLUSIONS

Potentially clinically relevant differences existed in RTclin for sex and sport type. These results provide normative data adjusting for these performance factors.

Soccer-Related Concussions Among Swedish Elite Soccer Players: A Descriptive Study of 1,030 Players

Objective: There are growing concerns about the short- and long-term consequences of sports-related concussion, which account for about 5–9% of all sports injuries. We hypothesized there may be sex differences in concussion history and concussion-related symptoms, evaluated among elite soccer players in Sweden.

Design: Retrospective survey study.

Participants and Setting: Soccer players (n = 1,030) from 55 Swedish elite soccer teams. Questionnaires were completed prior to the start of the 2017 season.

Assessment of Risk Factors: Player history of soccer-related concussion (SoRC), symptoms and management following a SoRC were evaluated.

Main Outcome Measures: Before the start of the season the players completed a baseline questionnaire assessing previous concussions. The Sports Concussion Assessment Tool 3 was included with regard to symptom evaluation.

Results: Out of 993 responding players 334 (34.6%) reported a previous SoRC and 103 players (10.4%) reported a SoRC during the past year. After sustaining a SoRC, 114 players (34.2%) reported that they continued their ongoing activity without a period of rest, more commonly female (44.9%) than male players (27.7%; P = 0.002). Symptom resolution time was 1 week or less for 61.3% of the players that reported having persisting symptoms. A positive correlation was observed between number of previous concussions and prevalence of three persisting symptoms: fatigue (P < 0.001), concentration/memory issues (P = 0.002) and headache (P = 0.047).

Conclusion: About 35% of male and female elite soccer players in Sweden have experienced a previous SoRC, and about 10% experienced a SoRC during the last year. Female players continued to play after a SoRC, without a period of rest, more often than males. A higher risk of persisting symptoms was observed in players with a history of multiple concussions.

Reliability of the Sport Concussion Assessment Tool 5 baseline testing: A 2-week test-retest study

OBJECTIVES

To examine short-term test-retest reliability of the Sport Concussion Assessment Tool 5 (SCAT5).

DESIGN

Longitudinal study.

METHODS

Sixty-two professional male ice hockey players (mean age=22.5, SD=3.2) completed a preseason baseline test twice over a two-week interval. Half of the players were tested by the same assessor on both testing sessions. Spearman's correlations (rs) were used to determine linear agreements, and Wilcoxon signed rank tests (sig r) were used to determine mean differences, between testing sessions.

RESULTS

Symptoms had high test-retest reliability (Score: rs=0.85, p<0.001, sig r p<0.001; Severity: rs=0.84, p<0.001, sig r p<0.001). The reliability coefficients for the SAC (rs=0.58, p<0.001, sig r: p=0.412), and mBESS (rs=0.40, p=0.001, sig r: p=0.607) were considerably lower than symptoms. More than half (52%) of the athletes reported at least one baseline symptom (Md=1, M=2.2, SD=3.3). The most commonly reported symptoms were fatigue or low energy and neck pain. The broad ranges of SAC total scores (range=28-45, Md=35, M=35.4, SD=4.2) and SAC test-retest change scores (range -7 to +11) were mostly due to variability on the memory performance, tested using 10-item word lists. The number of mBESS single leg stance errors (Md=1, Md 3.2, SD=4.0) was greater than Tandem stance errors (Md=0, Md=2.0, SD=3.6).

CONCLUSIONS

The two-week test-retest reliability of the SCAT5 baseline scores varied from moderate to high. However, there was considerable individual variability on the SAC and mBESS scores and most players have notable short-term fluctuation on performance even if uninjured. Recommendations for interpreting change on the SCAT5 are provided.

Exploring Baseline Concussion-Assessment Performance in Adapted Wheelchair Sport Athletes

CONTEXT

With growing awareness of and advocacy for including individuals with disabilities in sport, implementation of concussion-assessment and -management strategies is warranted. Limited research is available on concussion assessment in adapted wheelchair sport athletes.

OBJECTIVE

To examine baseline symptom reporting, computerized neurocognitive testing, and a modified balance scoring system in adapted athletes. A secondary objective was to provide preliminary normative data for this population.

DESIGN

Cross-sectional study.

SETTING

University athletic training room and computer laboratory.

PATIENTS OR OTHER PARTICIPANTS

Twenty-one athletes (age = 22.1 ± 3.0 years) from 1 institution's collegiate adapted athletics program.

MAIN OUTCOME MEASURE(S)

Athletes completed baseline Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) and the Wheelchair Error Scoring System (WESS) before the start of their respective seasons. Symptom reporting variables consisted of total symptoms, symptom severity scores, and baseline symptom factors (eg, vestibular-somatic, sleep arousal, cognitive-sensory, and affective). We analyzed ImPACT composite scores of verbal memory, visual memory, visual motor processing speed, and reaction time and impulse control to determine neurocognitive function. Balance performance was quantified using the WESS condition and overall errors.

RESULTS

Compared with normative reference values, 17 (81%) of adapted athletes reported greater symptoms and 20 (95%) performed at or below average on at least 1 neurocognitive composite score. Mean errors on the WESS were 3.14 ± 2.9, with 81% committing ≥1 error. Sex differences were not present for symptoms, neurocognitive testing, or balance measures.

CONCLUSIONS

Our findings provide context for baseline performance in adapted athletes and help to further develop the WESS as an assessment of balance in these athletes.

Exploratory Analysis of Concussion Recovery Trajectories using Multi-modal Assessments and Serum Biomarkers

Clinicians need better tools to assess severity, prognosis, and recovery from mild Traumatic Brain Injury (mTBI), which can cause long term impairment. To enable better mTBI outcome prediction, an initial step is to analyze the trajectory of recovery metrics over time. This study provides an assessment of recovery trajectories of mTBI while incorporating heterogeneity of individual responses. We analyze the trajectories over multiple discrete time points from baseline to 6 months post injury using a combination of neurocognitive and postural stability assessments and serum biomarkers. The data, obtained from FITBIR, consists of concussed subjects and a matched control group, to allow for comparison in prognostic assessment. Outcomes derived from this exploratory analysis will aid future studies in developing a mTBI recovery timeline model.Clinical relevance- This study further informs clinicians as to the recovery trajectory of clinical measures and biomarkers after mTBI to support return to play decisions. GFAP biomarker and measures related to balance, memory, orientation, and concentration were significantly different than controls early after mTBI.

Using Variance to Explore the Diagnostic Utility of Baseline Concussion Testing

The Graded Symptom Checklist (GSC), Standardized Assessment of Concussion (SAC), Balance Error Scoring System (BESS), and King-Devick Test (KDT) are considered important components of concussion assessment. Whether baseline testing improves the diagnostic utility of these tests remains unclear. We performed an observational cohort study to investigate the within-subject and between-subjects variability of these tests over repeated assessments during two football seasons to examine whether baseline testing reduces variability in test performance. Thirty-five male collegiate football players completed weekly clinical concussion assessments over two seasons. Within-subject (week-to-week) and between-subjects (player-to-player) variability for each test were compared using a bootstrap analysis. Within-subject and between-subjects proportions of overall variance for each test score were calculated. Mixed-model analyses were used to quantify practice effects resulting from repeated testing. For the GSC and BESS, within-subject and between-subjects variability did not significantly differ. For the KDT, the proportion of within-subject variance (20.2%) was significantly less than the between-subjects variance (79.8%). For SAC, however, the proportion of within-subject variance (66.8%) was significantly greater than the between-subjects variance (33.8%). A small, but significant, practice effect was observed for the BESS and KDT tests. When athletes are evaluated during a football season for concussion using the GSC, SAC, and BESS, comparing their scores to baseline performance is likely no more beneficial than comparing them to normative population data for identifying neurological changes associated with concussion. For the KDT, comparison to baseline testing is likely beneficial because of significantly higher between-subjects variability.