The Interval Between Concussions Does Not Influence Time to Asymptomatic or Return to Play: A CARE Consortium Study.

INTRODUCTION: The purpose of this study was to determine if the time interval between two concussive events influences the number of days to asymptomatic status, days to return to play, or performance on common post-concussion assessments following the second concussion. METHODS: Data from 448 collegiate athletes and service academy cadets with two concussions (time between concussions: median 295.0 days [interquartile range: 125.0-438.2]), 40.0% female) were analyzed from Concussion Assessment Research and Education (CARE) Consortium institutions between 2014 and 2020. Days between concussions was the primary predictor variable. Primary outcome measures included time to asymptomatic and time to return to play following the second concussion. Secondary outcome measures included total number of symptoms, total symptom severity, Balance Error Scoring System total score, and Standardized Assessment of Concussion total score within 48 h of their second concussion. RESULTS: Time between concussions did not significantly contribute to the multivariate time to asymptomatic (p = 0.390), time to return to play (p = 0.859), or the secondary outcomes (p-range = 0.165-0.477) models. Time to asymptomatic (p = 0.619) or return to play (p = 0.524) did not differ between same-season and different-season concussions. Sex significantly contributed to the return to play (p = 0.005) multivariate model. Delayed symptom onset and immediate removal from play/competition significantly contributed to the total number of symptoms (p = 0.001, p = 0.014) and symptom severity (p = 0.011, p = 0.022) multivariate models. CONCLUSION: These results suggest that in a population with a large period between injuries, the time between concussions may not be relevant to clinical recovery.

Mechanisms of Injury Leading to Concussions in Collegiate Soccer Players: A CARE Consortium Study.

BACKGROUND: Few previous studies have investigated how different injury mechanisms leading to sport-related concussion (SRC) in soccer may affect outcomes. PURPOSE: To describe injury mechanisms and evaluate injury mechanisms as predictors of symptom severity, return to play (RTP) initiation, and unrestricted RTP (URTP) in a cohort of collegiate soccer players. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: The Concussion Assessment, Research and Education (CARE) Consortium database was used. The mechanism of injury was categorized into head-to-ball, head-to-head, head-to-body, and head-to-ground/equipment. Baseline/acute injury characteristics-including Sports Concussion Assessment Tool-3 total symptom severity (TSS), loss of consciousness (LOC), and altered mental status (AMS); descriptive data; and recovery (RTP and URTP)-were compared. Multivariable regression and Weibull models were used to assess the predictive value of the mechanism of injury on TSS and RTP/URTP, respectively. RESULTS: Among 391 soccer SRCs, 32.7% were attributed to a head-to-ball mechanism, 27.9% to a head-to-body mechanism, 21.7% to a head-to-head mechanism, and 17.6% to a head-to-ground/equipment mechanism. Event type was significantly associated with injury mechanism [χ2(3) = 63; P < .001), such that more head-to-ball concussions occurred in practice sessions (n = 92 [51.1%] vs n = 36 [17.1%]) and more head-to-head (n = 65 [30.8%] vs n = 20 [11.1]) and head-to-body (n = 76 [36%] vs n = 33 [18.3%]) concussions occurred in competition. The primary position was significantly associated with injury mechanism [χ2(3) = 24; P < .004], with goalkeepers having no SRCs from the head-to-head mechanism (n = 0 [0%]) and forward players having the least head-to-body mechanism (n = 15 [19.2%]). LOC was also associated with injury mechanism (P = .034), with LOC being most prevalent in head-to-ground/equipment. Finally, AMS was most prevalent in head-to-ball (n = 54 [34.2%]) and head-to-body (n = 48 [30.4%]) mechanisms [χ2(3) = 9; P = .029]. In our multivariable models, the mechanism was not a predictor of TSS or RTP; however, it was associated with URTP (P = .044), with head-to-equipment/ground injuries resulting in the shortest mean number of days (14 ± 9.1 days) to URTP and the head-to-ball mechanism the longest (18.6 ± 21.6 days). CONCLUSION: The mechanism of injury differed by event type and primary position, and LOC and AMS were different across mechanisms. Even though the mechanism of injury was not a significant predictor of acute symptom burden or time until RTP initiation, those with head-to-equipment/ground injuries spent the shortest time until URTP, and those with head-to-ball injuries had the longest time until URTP.

Improving post-concussion discharge education for families seeking emergency department care: intervention development.

BACKGROUND: Pediatric emergency departments (ED) are where many families receive post-concussion medical care and thus an important context for helping parents build skills to support their child after discharge. OBJECTIVE: Develop a strategy for increasing parent provision of emotional and instrumental support to their child after discharge and conduct a pilot test of this strategy's acceptability. METHODS: In a large pediatric ED in the United States, we partnered with parents (n = 15) and clinicians (n = 15) to understand needs and constraints related to discharge education and to operationalize a strategy to feasibly address these needs. This produced a brief daily text message intervention for parents for 10 days post-discharge. We used a sequential cohort design to assess the acceptability this intervention and its efficacy in changing parenting practices in the 2-weeks post-discharge (n = 98 parents). RESULTS: Parents who received the messaging intervention rated it as highly acceptable and had meaningfully higher scores for emotionally supportive communication with their child in the two weeks post-discharge than parents in the control condition (Cohen's d = 0.65, p = 0.021). CONCLUSIONS: This brief messaging intervention is a promising strategy for enhancing discharge education post-concussion that warrants further evaluation.

Postinjury Alcohol Use Is Associated With Prolonged Recovery After Concussion in NCAA Athletes.

OBJECTIVE: To determine whether alcohol use leads to prolonged clinical recovery or increased severity of concussion symptoms in National Collegiate Athletic Association (NCAA) athletes. DESIGN: Prospective observational study. SETTING: Clinical institutions. PARTICIPANTS: Athletes from the NCAA Concussion Assessment Research and Education consortium who sustained a concussion from 2014 to 2021. INTERVENTIONS: Athletes were divided into 2 groups, those reporting alcohol use postinjury and those reporting no alcohol use postinjury. MAIN OUTCOME MEASURES: Symptom recovery was evaluated as time (in days) from injury to clearance to return to unrestricted play (days until URTP). Severity of concussion symptoms was assessed using the Standardized Sport Concussion Assessment Tool (SCAT3) symptom severity, headache severity, difficulty concentrating, and difficulty remembering scores. These scores were taken a median of 6.6 [interquartile range (IQR) = 4.0-10] and 6 (IQR = 4.0-9.0) days after injury for those who did and did not consume alcohol postinjury respectively and compared with baseline SCAT3 scores. RESULTS: Four hundred eighty four athletes from the data set had complete data for exposure and outcome. The adjusted mean number of days until URTP for athletes reporting alcohol use postinjury [23.3; 95% confidence interval (CI), 20.0-27.2; days] was incidence rate ratio (IRR) 1.32 (95% CI, 1.12-1.55; P < 0.001) times higher than for athletes who reported no alcohol use postinjury [17.7 (95% CI, 16.1-19.3) days]. Postinjury alcohol was not associated with severity of concussion symptoms ( P 's < 0.05). CONCLUSION: Self-reported postinjury alcohol use is associated with prolonged recovery but not severity of concussion symptoms in collegiate athletes. This may inform future clinical recommendations regarding alcohol consumption after concussion.

Postinjury Outcomes After Non-Sport-Related Concussion: A CARE Consortium Study.

CONTEXT: Concussion research has primarily focused on sport-related mechanisms and excluded non-sport-related mechanisms. In adult populations, non-sport-related concussions (non-SRCs) demonstrated worse clinical outcomes compared with sport-related concussions (SRCs); however, investigations of non-SRCs in college-aged patients are limited. OBJECTIVES: To examine clinical outcomes in collegiate athletes with non-SRCs compared with SRCs and explore sex differences in outcomes among collegiate athletes with non-SRCs. DESIGN: Prospective cohort study. SETTING: Clinical setting. PATIENTS OR OTHER PARTICIPANTS: A total of 3500 athletes were included (n = 555 with non-SRCs, 42.5% female) from colleges or universities and service academies participating in the National Collegiate Athletic Association Department of Defense Concussion Assessment, Research and Education (CARE) Consortium. MAIN OUTCOME MEASURE(S): Dichotomous outcomes (yes or no) consisted of immediate reporting, mental status alterations, loss of consciousness, posttraumatic amnesia, retrograde amnesia, motor impairments, delayed symptom presentation, and required hospital transport. Continuous outcomes were symptom severity, days with concussion symptoms, and days lost to injury. Data were collected within 24 to 48 hours of injury and at return to play. Adjusted relative risks (ARRs) compared the likelihood of dichotomous outcomes by mechanism and by sex within patients with non-SRCs. Multivariate negative binomial regressions were used to assess group differences in continuous variables. RESULTS: Athletes with non-SRCs were less likely to report immediately (ARR = 0.73, 95% CI = 0.65, 0.81) and more likely to report delayed symptom presentation (ARR = 1.17, 95% CI = 1.03, 1.32), loss of consciousness (ARR = 3.15, 95% CI = 2.32, 4.28), retrograde amnesia (ARR = 1.77, 95% CI = 1.22, 2.57), and motor impairment (ARR = 1.45, 95% CI = 1.14, 1.84). Athletes with non-SRCs described greater symptom severity, more symptomatic days, and more days lost to injury (P < .001) compared with those who had SRCs. Within the non-SRC group, female athletes indicated greater symptom severity, more symptomatic days, and more days lost to injury (P < .03) than male athletes. CONCLUSIONS: Athletes with non-SRCs had worse postinjury outcomes compared with those who had SRCs, and female athletes with non-SRCs had worse recovery metrics than male athletes. Our findings suggest that further investigation of individuals with non-SRCs is needed to improve concussion reporting and management.

CARE4Kids Study: Endophenotypes of Persistent Post-Concussive Symptoms in Adolescents: Study Rationale and Protocol.

Treatment of youth concussion during the acute phase continues to evolve, and this has led to the emergence of guidelines to direct care. While symptoms after concussion typically resolve in 14-28 days, a portion (∼20%) of adolescents endorse persistent post-concussive symptoms (PPCS) beyond normal resolution. This report outlines a study implemented in response to the National Institute of Neurological Diseases and Stroke call for the development and initial clinical validation of objective biological measures to predict risk of PPCS in adolescents. We describe our plans for recruitment of a Development cohort of 11- to 17-year-old youth with concussion, and collection of autonomic, neurocognitive, biofluid, and imaging biomarkers. The most promising of these measures will then be validated in a separate Validation cohort of youth with concussion, and a final, clinically useful algorithm will be developed and disseminated. Upon completion of this study, we will have generated a battery of measures predictive of high risk for PPCS, which will allow for identification and testing of interventions to prevent PPCS in the most high-risk youth.

Sex Differences in Recovery Trajectories of Assessments for Sport-Related Concussion Among NCAA Athletes: A CARE Consortium Study.

OBJECTIVES: The purpose of this study was to determine sex differences in recovery trajectories of assessments for sport-related concussion using Concussion Assessment, Research and Education (CARE) Consortium data. METHODS: National Collegiate Athletic Association athletes (N = 906; 61% female) from sex-comparable sports completed a pre-season baseline assessment and post-sport-related concussion assessments within 6 h of injury, 24-48 h, when they initiated their return to play progression, when they were cleared for unrestricted return to play, and 6 months post-injury. Assessments included the Standardized Assessment of Concussion, Balance Error Scoring System, Brief Symptom Inventory-18, Immediate Post-concussion Assessment and Cognitive Testing (ImPACT), Sport Concussion Assessment Tool-3 symptom evaluation, Clinical Reaction Time, King-Devick test, Vestibular Ocular Motor Screen, 12-item Short-Form Health Survey, Hospital Anxiety and Depression Scale, and Satisfaction with Life Scale. RESULTS: Only the Vestibular Ocular Motor Screen Total Symptom Score at the 24-48 h timepoint (p = 0.005) was statistically significantly different between sexes. Specifically, female athletes (mean = 60.2, 95% confidence interval [CI] 51.5-70.4) had higher Vestibular Ocular Motor Screen Total Symptom Scores than male athletes (mean = 36.9, 95% CI 27.6-49.3), but this difference resolved by the time of return-to-play initiation (female athletes, mean = 1.8, 95% CI 1.1-2.9; male athletes, mean = 4.1, 95% CI 1.5-10.9). CONCLUSIONS: Sport-related concussion recovery trajectories for most assessments were similar for female and male National Collegiate Athletic Association athletes except for Vestibular Ocular Motor Screen symptoms within 48 h of sport-related concussion, which was greater in female athletes. Female athletes had a greater symptom burden across all timepoints, suggesting that cross-sectional observations may indicate sex differences despite similar recovery trajectories.

Initial Mild Traumatic Brain Injury Characteristics and Recovery Patterns Among Females Across the United States Military Service Academies: A Report from the NCAA-DoD CARE Consortium.

Mild traumatic brain injury (mTBI) has been described in the United States (US) military service academy cadet population, but female-specific characteristics and recovery outcomes are poorly characterized despite sex being a confounder. Our objective was to describe female cadets' initial characteristics, assessment performance, and return-to-activity outcomes post-mTBI. Female cadets (n = 472) from the four US military service academies who experienced a mTBI completed standardized mTBI assessments from pre-injury to acute initial injury and unrestricted return-to-duty (uRTD). Initial injury presentation characteristics (e.g., delayed symptoms, retrograde amnesia) and return-to-activity outcomes [i.e., return-to-learn, initiate return-to-duty protocol (iRTD), uRTD] were documented. Descriptive statistics summarized female cadets' injury characteristics, return-to-activity outcomes, and post-mTBI assessment performance change categorization (worsened, unchanged, improved) relative to pre-injury baseline using established change score confidence rank criteria for each assessment score. The median (interquartile range) days to return-to-learn (n = 157) was 7.0 (3.0-14.0), to iRTD (n = 412) was 14.7 (8.6-25.8), and to uRTD (n = 431) was 26.0 (17.7-41.8). The majority experienced worse SCAT total symptom severity (77.8%) and ImPACT reaction time (97.0%) acutely < 24-h versus baseline, but unchanged BESS total errors (75.2%), SAC total score (72%), BSI-18 total score (69.6%), and ImPACT verbal memory (62.3%), visual memory (58.4%), and visual motor speed (52.5%). We observed similar return-to-activity times in the present female cadet cohort relative to the existing female-specific literature. Confidence ranks categorizing post-mTBI performance were heterogenous and indicate multimodal assessments are necessary. Our findings provide clinically relevant insights to female cadets experiencing mTBI across the US service academies for stakeholders providing healthcare.

Female Collegiate Athletes' Concussion Characteristics and Recovery Patterns: A Report from the NCAA-DoD CARE Consortium.

Concussion has been described in the United States (US) collegiate student-athlete population, but female-specific findings are often underrepresented and underreported. Our study aimed to describe female collegiate student-athletes' initial injury characteristics and return to activity outcomes following concussion. Female collegiate student-athletes (n = 1393) from 30-US institutions experienced a concussion and completed standardized, multimodal concussion assessments from pre-injury through unrestricted return to play (uRTP) in this prospective, longitudinal cohort study. Initial injury presentation characteristics, assessment, and return to activity outcomes [<48-h (acute), return to learn, initiate return to play (iRTP), uRTP] were collected. We used descriptive statistics to report injury characteristics, return to activity outcomes, and post-injury assessment performance change categorization (worsened, unchanged, improved) based on change score confidence rank criteria across sport contact classifications [contact (n = 661), limited (n = 446), non-contact (n = 286)]. The median (25th to 75th percentile) days to return to learn was 6.0 (3.0-10.0), iRTP was 8.1 (4.8-13.8), and uRTP was 14.8 (9.9-24.0), but varied by contact classification. Across contact levels, the majority experienced worse SCAT total symptom severity (72.8-82.6%), ImPACT reaction time (91.2-92.6%), and BSI-18 total score (45.2-51.8%) acutely relative to baseline, but unchanged BESS total errors (58.0-60.9%), SAC total score (71.5-76.1%), and remaining ImPACT domains (50.6-66.5%). Our findings provide robust estimates of the typical female collegiate student-athlete presentation and recovery trajectory following concussion, with overall similar findings to the limited female collegiate student-athlete literature. Overall varying confidence rank classification was observed acutely. Our findings provide clinically-relevant insights for athletes, clinicians, researchers, and policymakers to inform efforts specific to females experiencing concussion.

Incidence of concussion and associated risk factors in collegiate soccer: findings from the NCAA-DoD CARE consortium.

This retrospective cohort study aims to examine concussion incidence rates (IR) in collegiate soccer players and compare IRs based on risk factors including sex, competition level, games/practices, history of concussion, and playing position. Collegiate soccer players were recruited (n = 2,471) from 23 institutions from the NCAA-DoD Concussion Assessment, Research, and Education (CARE) Consortium. Incidence rates for concussion per 1000 athlete exposures (AEs) were calculated across the 2015-16/2016-17 seasons. Incidence rates (IR) comparing risk factor groups were also calculated. A total of 162 concussions occurred during the study, for an IR of 0.08/1000 AEs. Females were more likely to have a concussion than males overall (IR = 1.47) and were more likely to have a concussion in games (IR = 1.42) and practices (IR = 2.91). Concussions were more likely during competition compared to practice (IR = 2.53), and less likely in Division III, compared to Divisions I and II, χ2 = 6.5, p > .05. In the concussed group, male sex was associated with 2.47 times higher odds of playing defender and 2.29 times higher odds of a collision mechanism. Results confirm previous findings that females and game exposures have higher concussion IR than males and practice exposures. Findings also supported sex differences in IRs based on exposure type, position, and mechanism.

Psychometric Properties and Validation of the General Anxiety Disorder 7-Item Scale Among Adolescents With Persistent Post-Concussive Symptoms.

The General Anxiety Disorder 7-Item (GAD-7) scale is commonly used in primary care as a self-report measure of general anxiety symptoms with adult populations. There is little psychometric research on this measure with adolescent populations, particularly those with persistent post-concussive symptoms (PPCS). This study examined the psychometrics properties of the GAD-7 among youth with PPCS. We used baseline data from a randomized controlled trial of collaborative care for treatment of PPCS among 200 sports-injured adolescents 11-18 years of age (Mage = 14.7 years, standard deviation = 1.7). Eligible adolescents had three or more PPCS that lasted for ≥1 month and spoke English. Adolescents reported on their anxious (GAD-7 and Revised Child Anxiety and Depression Scale-Short Version [anxiety subscale]; RCADS) and depressive (Patient Health Questionnaire-9; PHQ-9) symptoms. Parents used the RCADS to report on their adolescents' anxious symptoms. The GAD-7 had good internal validity (Cronbach's alpha = 0.87), and significant (p < 0.001) correlations were detected between the GAD-7 and youth and parent report of anxiety on RCADS (r = 0.73 and r = 0.29) and PHQ-9 (r = 0.77) scores. Confirmatory factor analysis suggested a one-factor solution. These results suggest that the GAD-7 is a valid measure of anxiety with good psychometric properties for youth experiencing PPCS. ClinicalTrials.gov identifier: NCT03034720.

Development of a Measure of Parent Concussion Management Knowledge and Self-Efficacy.

Abstract Assessing parent readiness to support their child's post-concussion management requires valid and reliable measures. Therefore, the objective of this study was to develop and conduct preliminary tests of reliability and validity of survey measures of parent concussion management knowledge and self-efficacy. Additionally, we tested the hypothesis that among parents of youth who had sustained a concussion, higher scores on measures of knowledge and self-efficacy would predict greater likelihood of engaging in recommended concussion management behaviors during their child's recovery. Measure development occurred with reference to parenting behaviors included in the Center for Disease Control and Prevention's Pediatric Mild Traumatic Brain Injury (mTBI) Management Guidelines. A multi-stage mixed- methods approach was employed, including expert review, cognitive interviews with parents, quantitative item reduction, and tests of reliability and validity. All participants were English-speaking parents of school-aged children in the United States. A stepwise measure development process was followed, with different participant groups across steps (including opt-in web-based survey panels and in-person recruitment from the population of parents of pediatric patients seen in a large pediatric emergency department). In total, 774 parents participated in study activities. The final knowledge index had 10 items, and the final self-efficacy scale had 13 items across four subscales (emotional support, rehabilitation support, monitoring, and external engagement). Internal consistency reliability was 0.63 for the knowledge index and 0.79-0.91 for self-efficacy sub-scales, and validation tests were in the hypothesized directions. In a test of predictive validity, we observed that among parents of youth patients with recent concussion, higher self-efficacy scores at the time of discharge from the pediatric emergency department were positively correlated (r = 0.12) with greater likelihood of engaging in recommended support behaviors at 2-week follow-up. There was no association between concussion management knowledge at discharge and parenting behaviors at follow-up. Parents have the potential to play an important role in concussion management. The measures of knowledge and self-efficacy developed in this study can help identify parent needs and evaluate interventions aiming to support parenting post-concussion.

Developing a conceptual model of coach concussion communication by adapting the theory of planned behavior and the social ecological model.

Objective: Acknowledging that coach communication about concussion increases the likelihood of athletes reporting concussive symptoms, the goal of this study was to examine factors affecting such communication, in order to develop a conceptual model that would inform the design of future educational interventions.Participants: Division I contact sport coaches.Methods: We conducted structured qualitative interviews with coaches and analyzed interviews using Thematic Analysis, viewed through the lens of the Theory of Planned Behavior nested within the Social Ecological Model.Results: Coaches had good knowledge of concussion and understood the dangers of playing with symptoms. However, they also discussed the lack of objective criteria for concussion diagnosis, and pressure to win in order to remain employed, both of which created barriers to concussion communication. Ultimately, most coaches reported not engaging in significant concussion communication as they did not feel this was their role, instead deferring to medical staff.Conclusions: Educational interventions might benefit from a focus on the importance of coach concussion safety-supportive coach communication, with a goal of increasing the likelihood of athlete concussion reporting.

Optimizing Concussion Care Seeking: A Longitudinal Analysis of Recovery.

BACKGROUND: Approximately half of concussions go undisclosed and therefore undiagnosed. Among diagnosed concussions, 51% to 64% receive delayed medical care. Understanding the influence of undiagnosed concussions and delayed medical care would inform medical and education practices. PURPOSE: To compare postconcussion longitudinal clinical outcomes among (1) individuals with no concussion history, all previous concussions diagnosed, and ≥1 previous concussion undiagnosed, as well as (2) those who have delayed versus immediate symptom onset, symptom reporting, and removal from activity after concussion. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Participants included 2758 military academy cadets and intercollegiate athletes diagnosed with concussion in the CARE Consortium. We determined (1) each participant's previous concussion diagnosis status self-reported at baseline (no history, all diagnosed, ≥1 undiagnosed) and (2) whether the participant had delayed or immediate symptom onset, symptom reporting, and removal from activity. We compared symptom severities, cognition, balance, and recovery duration at baseline, 24 to 48 hours, date of asymptomatic status, and date of unrestricted return to activity using tests of parallel profiles. RESULTS: The ≥1 undiagnosed concussion group had higher baseline symptom burdens (P < .001) than the other 2 groups and poorer baseline verbal memory performance (P = .001) than the all diagnosed group; however, they became asymptomatic and returned to activity sooner than those with no history. Cadets/athletes who delayed symptom reporting had higher symptom burdens 24 to 48 hours after injury (mean ± SE; delayed, 28.8 ± 0.8; immediate, 20.6 ± 0.7), took a median difference of 2 days longer to become asymptomatic, and took 3 days longer to return to activity than those who had immediate symptom reporting. For every 30 minutes of continued participation after injury, days to asymptomatic status increased 8.1% (95% CI, 0.3%-16.4%). CONCLUSION: Clinicians should expect that cadets/athletes who delay reporting concussion symptoms will have acutely higher symptom burdens and take 2 days longer to become asymptomatic. Educational messaging should emphasize the clinical benefits of seeking immediate care for concussion-like symptoms.

Cognitive and Behavioral Outcomes in Male and Female NCAA Soccer Athletes across Multiple Years: A CARE Consortium Study.

PURPOSE: The purpose of this study was to determine changes in neurocognitive, psychosocial, and balance functioning in collegiate male and female soccer players across three consecutive years of baseline testing compared with a control group of noncontact athletes. METHODS: Generalized estimating equations were used to compare changes in annual, preseason baseline measures of neurocognitive function, neurobehavioral and psychological symptoms, and postural stability between collegiate soccer players ( n = 75; 51 [68%] female soccer players) and noncontact athletes ( n = 210; 133 [63%] female noncontact athletes) across three consecutive years. RESULTS: Among all participants, the group-time interaction was not significant for any outcome measures. Overall, soccer players reported lower (better) Brief Symptom Inventory 18 Depression ( P = 0.004, Exp(B) = 0.36, 95% confidence interval [CI] = 0.18-0.73), Global Severity Index ( P = 0.006, Exp(B) = 0.53, 95% CI = 0.33-0.84), and Post-Concussion Symptom Scale Symptom Severity ( P < 0.001, Exp(B) = 0.45, 95% CI = 0.22-0.95) scores than noncontact athletes. No other outcome measures were different between soccer players and noncontact athletes. CONCLUSIONS: Among collegiate athletes, soccer players report similar or better psychosocial functioning and symptom scores than noncontact athletes. Importantly, neurocognitive functioning, neurobehavioral and psychological symptoms, and postural stability do not worsen over time in collegiate soccer players relative to their noncontact counterparts. Our findings suggest that despite possible exposure to repetitive head impacts, collegiate soccer players do not exhibit changes in observable function and symptoms across multiple seasons.

Concussion education for youth athletes using Pre-Game Safety Huddles: a cluster-randomised controlled trial.

OBJECTIVES: Determine whether Pre-Game Safety Huddles, a novel and low-resource approach to concussion education, increase the expected likelihood of concussion reporting for youth athletes. METHODS: A cluster-randomised trial compared Safety Huddles to usual care. Safety Huddles bring together athletes and coaches from both teams before the start of each game for coaches to briefly affirm the importance of speaking up if a concussion is suspected. Participants were athletes from 22 competitive community-based American football and girls and boys soccer teams (ages 9-14), and randomisation into intervention or control occurred at the level of the bracket (group of teams that compete against each other during the regular season). The primary outcome was expected likelihood of reporting concussion symptoms to the coach, measured via validated athlete survey at the beginning and end of the season. RESULTS: Of 343 eligible participants, 339 (99%) completed baseline surveys and 303 (88%) completed surveys at season end. The mean (SD) age was 11.4 (1.1) years, 26% were female soccer athletes, 27% were male soccer athletes and 47% were football athletes. In adjusted analyses accounting for baseline values and clustering by sport and team via random effects, expected likelihood of concussion reporting at the end of the season was significantly higher in the intervention group compared to controls (mean difference=0.49, 95% CI 0.11 to 0.88; Cohen's d=0.35). CONCLUSIONS AND RELEVANCE: Pre-Game Safety Huddles increased the expected likelihood of athletes reporting concussion symptoms. While further study is warranted, sport organisations should consider this approach a promising low-resource option for improving concussion safety in their setting. TRIAL REGISTRATION NUMBER: NCT04099329.

King-Devick testing and concussion recovery time in collegiate athletes.

OBJECTIVES: To assess whether the King-Devick (KD) test is useful as a prognostic test for prolonged concussion symptoms by examining the relationship between a) change in performance on KD test from baseline to within two days post-injury and b) the absolute KD time at post-concussion testing, with an outcome of time to return to play (RTP). DESIGN: Prospective Cohort Study. METHODS: Collegiate varsity athletes in the Concussion Assessment, Research, and Education (CARE) Consortium completed baseline and post-injury King-Devick tests from 2014 to 2018. Two exposures were evaluated: 1) change in KD score from baseline to within two days post-injury and 2) absolute KD score within two days post-injury, adjusted for baseline KD. We used Cox proportional hazards models to analyze the relationships between these exposures and time to RTP post-concussion. RESULTS: A total of 309 concussion injuries were included. Median baseline KD score was 40.0 s (IQR: 35.8, 45.2). Median post-injury KD score was 45.8 s (IQR: 39.8, 57.1). Median number of days until RTP in this cohort was 11 (IQR: 8, 17). Post-injury KD score adjusted for baseline KD had a stronger association with time to RTP duration (HR: 0.99 (0.98, 1.00), p = 0.03) than the difference in KD score from baseline to post-injury (HR: 0.99 (0.99, 1.00), p = 0.07). CONCLUSIONS: Higher post-injury KD scores are associated with longer RTP. The association between KD post-concussion test and longer RTP warrants further investigation to assess the utility of the KD for prognostication in a clinical setting.

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.

Mechanisms of injury for concussions in collegiate soccer: an NCAA/DoD CARE consortium study.

OBJECTIVE: The purpose of this study was to describe the mechanism of injury (MOI) and examine factors associated with greater risk for specific MOIs involving concussions in collegiate soccer players. METHODS: Participants included 3,288 collegiate soccer players from 28 institutions across four competitive seasons, 2014-17. MOIs were documented for 262 soccer-related concussions during the study and placed into one of four categories: collisions, unintentional contact, aerial challenges, and others. RESULTS: 70% of the concussions occurred in DI soccer players. Collisions and unintentional contact were the MOIs that resulted in 66.5% of all concussions. DI and DIII soccer players sustained more concussions by unintentional contact versus collisions and aerial challenges when compared to their DII counterparts. Defenders were more likely than midfielders to sustain concussions by aerial challenges than collisions. As expected, the field players experienced more concussions as a result of collisions, unintentional contact, and aerial challenges when compared to goalkeepers. CONCLUSIONS: Future research should explore preventive strategies for decreasing collisions, especially during aerial challenges while heading the soccer ball, and unintentional contacts from errant balls in soccer in order to decrease concussion risk.

Stakeholder-Engaged Development of a Theory-Driven, Feasible, and Acceptable Approach to Concussion Education.

Concussion education is widely mandated and largely ineffective. Recent consensus guidance on concussion education asserts the importance of (1) theory-driven programming that targets the team as a system and (2) working with end users throughout the development process, and considering issues such as feasibility, acceptability, and sustainability. Consistent with this guidance, and in collaboration with youth sport stakeholders in two regions of the United States, we developed a novel approach to concussion education: Pre-game safety huddles. Safety huddles have the following two core components: (1) athletes, coaches, and other stakeholders come together before the start of each game and (2) opinion leaders (coaches, referees) affirm the importance of care seeking for suspected concussion. The aim of this article is to provide an overview of the collaborative process through which we refined the safety huddle concept into an acceptable and feasible intervention with potential for sustainable implementation in diverse youth sports settings with minimal resource demands. In describing our process and discussing challenges and opportunities, we hope to provide an example for others seeking to develop and implement injury prevention interventions in youth sports settings.