Are Self-Reported and Parent-Reported Attention Problems and Hyperactivity Associated With Higher Rates of Concussion in Youth Ice Hockey Players?

OBJECTIVE: To examine the association between self-reported and parent-reported attention problems and hyperactivity and rates of injury and concussion in Canadian youth ice hockey players. DESIGN: Secondary analyses of 2 prospective cohort studies. SETTING: Canadian youth ice hockey teams. PARTICIPANTS: Ice hockey players (ages 11-17 years) were recruited by team, over 4 seasons (2011-2016). A combined 1709 players contributing 1996 player-seasons were analyzed (257 players participated in more than one season). ASSESSMENT OF RISK FACTORS: Data were collected from preseason baseline questionnaires, including child and parent proxy forms of the Behavior Assessment System for Children, second edition. MAIN OUTCOME MEASURES: Injury and concussion rates and incidence rate ratios (IRR) comparing players with and without self-identified or parent-identified attention problems and hyperactivity, adjusted for covariates (ie, body checking policy, previous injury/concussion, and age) and a random effect for team, were estimated using multiple multilevel negative binomial regression. RESULTS: When analyzed continuously, rates of concussion increased with higher self-reported and parent-reported measures of attention problems [IRR SELF = 1.025; 95% confidence interval (CI): 1.011-1.040; IRR PARENT = 1.032; 95% CI: 1.008-1.057]. Self-reported hyperactivity was significantly associated with concussion (IRR = 1.021; 95% CI: 1.007-1.035), but parent-reported hyperactivity was not (IRR = 1.005; 95% CI: 0.983-1.028). A T score ≥ 60 cutoff combining attention problems and hyperactivity scores (an estimate of probable attention-deficit hyperactivity disorder) was not significantly associated with rates of injury or concussion. CONCLUSIONS: Attention problems and hyperactivity may place youth ice hockey players at increased risk of concussion and injury. Preseason assessments could identify players for targeted concussion education and risk reduction strategies.

Factors Associated With Concussion Rates in Youth Ice Hockey Players: Data From the Largest Longitudinal Cohort Study in Canadian Youth Ice Hockey.

OBJECTIVES: To examine factors associated with rates of game and practice-related concussion in youth ice hockey. DESIGN: Five-year prospective cohort (Safe2Play). SETTING: Community arenas (2013-2018). PARTICIPANTS: Four thousand eighteen male and 405 female ice hockey players (6584 player-seasons) participating in Under-13 (ages 11-12), Under-15 (ages 13-14), and Under-18 (ages 15-17) age groups. ASSESSMENT OF RISK FACTORS: Bodychecking policy, age group, year of play, level of play, previous injury in the previous year, lifetime concussion history, sex, player weight, and playing position. MAIN OUTCOME MEASUREMENTS: All game-related concussions were identified using validated injury surveillance methodology. Players with a suspected concussion were referred to a study sport medicine physician for diagnosis and management. Multilevel Poisson regression analysis including multiple imputation of missing covariates estimated incidence rate ratios (IRRs). MAIN RESULTS: A total of 554 game and 63 practice-related concussions were sustained over the 5 years. Female players (IRR Female/Male = 1.79; 95% CI: 1.26-2.53), playing in lower levels of play (IRR = 1.40; 95% CI: 1.10-1.77), and those with a previous injury (IRR = 1.46; 95% CI: 1.13, 1.88) or lifetime concussion history (IRR = 1.64; 95% CI: 1.34-2.00) had higher rates of game-related concussion. Policy disallowing bodychecking in games (IRR = 0.54; 95% CI: 0.40-0.72) and being a goaltender (IRR Goaltenders/Forwards = 0.57; 95% CI: 0.38-0.87) were protective against game-related concussion. Female sex was also associated with a higher practice-related concussion rate (IRR Female/Male = 2.63; 95% CI: 1.24-5.59). CONCLUSIONS: In the largest Canadian youth ice hockey longitudinal cohort to date, female players (despite policy disallowing bodychecking), players participating in lower levels of play, and those with an injury or concussion history had higher rates of concussion. Goalies and players in leagues that disallowed bodychecking had lower rates. Policy prohibiting bodychecking remains an effective concussion prevention strategy in youth ice hockey.

Psychosocial Factors Associated With Time to Recovery After Concussion in Adolescent Ice Hockey Players.

OBJECTIVE: To investigate the association between psychosocial factors and physician clearance to return to play (RTP) in youth ice hockey players after sport-related concussion. DESIGN: Prospective cohort study, Safe to Play (2013-2018). SETTING: Youth hockey leagues in Alberta and British Columbia, Canada. PARTICIPANTS: Three hundred fifty-three ice hockey players (aged 11-18 years) who sustained a total of 397 physician-diagnosed concussions. INDEPENDENT VARIABLES: Psychosocial variables. MAIN OUTCOME MEASURES: Players and parents completed psychosocial questionnaires preinjury. Players with a suspected concussion were referred for a study physician visit, during which they completed the Sport Concussion Assessment Tool (SCAT3/SCAT5) and single question ratings of distress and expectations of recovery. Time to recovery (TTR) was measured as days between concussion and physician clearance to RTP. Accelerated failure time models estimated the association of psychosocial factors with TTR, summarized with time ratios (TRs). Covariates included age, sex, body checking policy, days from concussion to the initial physician visit, and symptom severity at the initial physician visit. RESULTS: Self-report of increased peer-related problems on the Strengths and Difficulties Questionnaire (TR, 1.10 [95% CI, 1.02-1.19]), higher ratings of distress about concussion outcomes by participants (TR, 1.06 [95% CI, 1.01-1.11]) and parents (TR, 1.05 [95% CI, 1.01-1.09]), and higher parent ratings of distress about their child's well-being at the time of injury (TR, 1.06 [95% CI, 1.02-1.09]) were associated with longer recovery. CONCLUSIONS: Greater pre-existing peer-related problems and acute distress about concussion outcomes and youth well-being predicted longer TTR. Treatment targeting these psychosocial factors after concussion may promote recovery.

Bodychecking experience and rates of injury among ice hockey players aged 15-17 years.

BACKGROUND: Although high rates of injury occur in youth ice hockey, disagreements exist about the risks and benefits of permitting bodychecking. We sought to evaluate associations between experience with bodychecking and rates of injury and concussion among ice hockey players aged 15-17 years. METHODS: We obtained data from a prospective cohort study of ice hockey players aged 15-17 years in Alberta who played in leagues that permitted bodychecking. We collected data over 3 seasons of play (2015/16-2017/18). We compared players based on experience with bodychecking (≤ 2 v. ≥ 3 yr), estimated using local and national bodychecking policy and region of play. We used validated methodology of ice hockey injury surveillance to identify all injuries related to ice hockey games and defined concussions according to the Consensus Statement on Concussion in Sport. RESULTS: We included 941 players who contributed to 1168 player-seasons, with 205 players participating in more than 1 season. Compared with players with 2 years or less of bodychecking experience, those with 3 or more years of experience had higher rates of all injury (adjusted incidence rate ratio [IRR] 2.55, 95% confidence interval [CI] 1.57-4.14), injury with more than 7 days of time loss (adjusted IRR 2.65, 95% CI 1.50-4.68) and concussion (adjusted IRR 2.69, 95% CI 1.34-5.42). INTERPRETATION: Among ice hockey players aged 15-17 years who participated in leagues permitting bodychecking, more experience with bodychecking did not protect against injury. This provides further support for removing bodychecking from youth ice hockey.

No association found between body checking experience and injury or concussion rates in adolescent ice hockey players.

OBJECTIVES: To compare rates of injury and concussion among U-15 (ages 13-14 years) ice hockey players playing in leagues allowing body checking, but who have a varying number of years of body checking experience. METHODS: This 5-year longitudinal cohort included U-15 ice hockey players playing in leagues where policy allowed body checking. Years of body checking experience were classified based on national/local body checking policy. All ice hockey game-related injuries were identified using a validated injury surveillance methodology. Players with a suspected concussion were referred to a study sport medicine physician. Multiple multilevel Poisson regression analysis was performed, adjusting for important covariates and a random effect at a team level (offset by game exposure hours), to estimate injury and concussion incidence rate ratios (IRRs). RESULTS: In total, 1647 players participated, contributing 1842 player-seasons (195 players participating in two seasons). Relative to no body checking experience, no significant differences were found in the adjusted IRRs for game-related injury for players with 1 year (IRR=1.06; 95% CI: 0.77 to 1.45) or 2+ years (IRR=1.16; 95% CI: 0.74 to 1.84) body checking experience. Similarly, no differences were found in the rates of concussion for players with 1 year (IRR=0.92; 95% CI: 0.59 to 1.42) or 2+ years (IRR=0.69; 95% CI: 0.38 to 1.25) body checking experience. CONCLUSIONS: Among ice hockey players aged 13-14 years participating in leagues permitting body checking, the adjusted rates of all injury and concussion were not significantly different between those that had body checking experience and those that did not. Based on these findings, no association was found between body checking experience and rates of injury or concussion specifically in adolescent ice hockey.

Body checking in non-elite adolescent ice hockey leagues: it is never too late for policy change aiming to protect the health of adolescents.

OBJECTIVES: The objective of this study is to evaluate the effect of policy change disallowing body checking in adolescent ice hockey leagues (ages 15-17) on reducing rates of injury and concussion. METHODS: This is a prospective cohort study. Players 15-17 years-old were recruited from teams in non-elite divisions of play (lower 40%-70% by division of play depending on year and city of play in leagues where policy permits or prohibit body checking in Alberta and British Columbia, Canada (2015-18). A validated injury surveillance methodology supported baseline, exposure-hours and injury data collection. Any player with a suspected concussion was referred to a study physician. Primary outcomes include game-related injuries, game-related injuries (>7 days time loss), game-related concussions and game-related concussions (>10 days time loss). RESULTS: 44 teams (453 player-seasons) from non-body checking and 52 teams (674 player-seasons) from body checking leagues participated. In body checking leagues there were 213 injuries (69 concussions) and in non-body checking leagues 40 injuries (18 concussions) during games. Based on multiple multilevel mixed-effects Poisson regression analyses, policy prohibiting body checking was associated with a lower rate of injury (incidence rate ratio (IRR): 0.38 (95% CI 0.24 to 0.6)) and concussion (IRR: 0.49; 95% CI 0.26 to 0.89). This translates to an absolute rate reduction of 7.82 injuries/1000 game-hours (95% CI 2.74 to 12.9) and the prevention of 7326 injuries (95% CI 2570 to 12083) in Canada annually. CONCLUSIONS: The rate of injury was 62% lower (concussion 51% lower) in leagues not permitting body checking in non-elite 15-17 years old leagues highlighting the potential public health impact of policy prohibiting body checking in older adolescent ice hockey players.

Sports-Related Concussions in Adults Presenting to Canadian Emergency Departments.

OBJECTIVE: To document the occurrence and recovery outcomes of sports-related concussions (SRCs) presenting to the Emergency Department (ED) in a community-based sample. DESIGN: A prospective observational cohort study was conducted in 3 Canadian hospitals. SETTING: Emergency Department. PATIENTS: Adults (≥17 years) presenting with a concussion to participating EDs with a Glasgow Coma Scale score ≥13 were recruited. INTERVENTIONS: Patient demographics (eg, age and sex), clinical characteristics (eg, history of depression or anxiety), injury characteristics (eg, injury mechanisms and loss of consciousness and duration), and ED management and outcomes (eg, imaging, consultations, and ED length of stay) were collected. MAIN OUTCOME MEASURES: Patients' self-reported persistent concussion symptoms, return to physical activity status, and health-related quality of life at 30 and 90 days after ED discharge. RESULTS: Overall, 248 patients were enrolled, and 25% had a SRC. Patients with SRCs were younger and reported more physical activity before the event. Although most of the patients with SRCs returned to their normal physical activities at 30 days, postconcussive symptoms persisted in 40% at 90 days of follow-up. After adjustment, there was no significant association between SRCs and persistent symptoms; however, patients with concussion from motor vehicle collisions were more likely to have persistent symptoms. CONCLUSION: Although physically active individuals may recover faster after a concussion, patients returning to their physical activities before full resolution of symptoms are at higher risk of persistent symptoms and further injury. Patient-clinician communications and tailored recommendations should be encouraged to guide appropriate acute management of concussions.

Association between Sensation-Seeking Behaviors and Concussion-Related Knowledge, Attitudes, Perceived Norms, and Care-Seeking Behaviors among Collegiate Student-Athletes.

There are limited data connecting personality and behavioral tendencies and traits related to concussion care-seeking/disclosure behaviors and minimal research exists surrounding the relationship between risky behaviors, sensation-seeking, and concussion-related outcomes. This study examined the association between sensation-seeking and a student-athlete's concussion-related knowledge, attitudes, perceived social norms, and concussion care-seeking/disclosure behaviors (intention to disclose concussion symptoms, perceived control over symptom disclosure, self-removal from play due to concussion symptoms, continued play with concussion symptoms, and disclosure of all concussions at the time of injury). The current study utilized a retrospective cohort of collegiate student-athletes at a single National Collegiate Athletic Association Division I institution. Separate multivariable linear regression models estimating mean differences (MD) and 95% Confidence Intervals (CI) estimated the association between sensation-seeking and concussion knowledge, concussion attitudes, and perceived social norms. Separate multivariable binomial regression models estimating adjusted prevalence ratios (PR) and 95%CI estimated the association between sensation-seeking and intention to disclose concussion symptoms, perceived control over symptom disclosure, self-removal from play due to concussion symptoms, continued play with concussion symptoms, and disclosure of all concussions at the time of injury. All models were adjusted for sex, sport participation, and concussion history. Higher sensation-seeking was significantly associated with less favorable concussion attitudes (adjusted MD = -1.93; 95%CI = -3.04,-0.83), less favorable perceived social norms surrounding concussion (adjusted MD = -1.39; 95%CI = -2.06,-0.72), and continuing to play while experiencing concussion symptoms (adjusted PR = 1.50; 95%CI = 1.10, 2.06). Student-athletes with increased sensation-seeking could be at risk for failing to disclose a concussion, decreasing athlete safety and resulting in less optimal care post-injury. Results will inform future theory-based concussion education programs which consider behavioral tendencies and traits as well as sport culture to promote concussion care-seeking/disclosure and individualized interventions based on risky behavior engagement.

Concussion Burden, Recovery, and Risk Factors in Elite Youth Ice Hockey Players.

OBJECTIVE: To examine rates of concussion and more severe concussion (time loss of greater than 10 days) in elite 13- to 17-year-old ice hockey players. METHODS: This is a prospective cohort study (Alberta, Canada). Bantam (13-14 years) and Midget (15-17 years) male and female elite (top 20% by division of play) youth ice hockey players participated in this study. Players completed a demographic and medical history questionnaire and clinical test battery at the beginning of the season. A previously validated injury surveillance system was used to document exposure hours and injury during one season of play (8 months). Players with a suspected ice hockey-related concussion were referred to the study sport medicine physicians for assessment. Time loss from hockey participation was documented on an injury report form. RESULTS: Overall, 778 elite youth ice hockey players (659 males and 119 females; aged 13-17 years) participated in this study. In total, 143 concussions were reported. The concussion incidence rate (IR) was 17.60 concussions/100 players (95% CI, 15.09-20.44). The concussion IR was 1.31 concussions/1000 player-hours (95% CI, 1.09-1.57). Time loss of greater than 10 days was reported in 74% of cases (106/143), and 20% (n = 28) had time loss of greater than 30 days. CONCLUSIONS: Concussion is a common injury in elite youth ice hockey players. In this study population, a large proportion of concussions (74%) resulted in a time loss of greater than 10 days, possibly reflecting more conservative management or longer recovery in youth athletes.

Does disallowing body checking in non-elite 13- to 14-year-old ice hockey leagues reduce rates of injury and concussion? A cohort study in two Canadian provinces.

OBJECTIVE: To compare rates of injury and concussion among non-elite (lowest 60% by division of play) Bantam (ages 13-14 years) ice hockey leagues that disallow body checking to non-elite Bantam leagues that allow body checking. METHODS: In this 2-year cohort study, Bantam non-elite ice hockey players were recruited from leagues where policy allowed body checking in games (Calgary/Edmonton 2014-2015, Edmonton 2015-2016) and where policy disallowed body checking (Kelowna/Vancouver 2014-2015, Calgary 2015-2016). All ice hockey game-related injuries resulting in medical attention, inability to complete a session and/or time loss from hockey were identified using valid injury surveillance methodology. Any player suspected of having concussion was referred to a study physician for diagnosis and management. RESULTS: 49 body checking (608 players) and 33 non-body checking teams (396 players) participated. There were 129 injuries (incidence rate (IR)=7.98/1000 hours) and 54 concussions (IR=3.34/1000 hours) in the body checking teams in games. After policy change, there were 31 injuries (IR=3.66/1000 hours) and 17 concussions (IR=2.01/1000 hours) in games. Policy disallowing body checking was associated with a lower rate of all injury (adjusted incidence rate ratio (IRR)=0.44; 95% CI: 0.27 to 0.74). The point estimate showed a lower rate of concussion (adjusted IRR=0.6; 95% CI: 0.31 to 1.18), but this was not statistically significant. CONCLUSION: Policy change disallowing body checking in non-elite Bantam ice hockey resulted in a 56% lower rate of injury. There is growing evidence that disallowing body checking in youth ice hockey is associated with fewer injuries.

Concussion diagnoses among adults presenting to three Canadian emergency departments: Missed opportunities.

OBJECTIVES: Patients with concussion commonly present to the emergency department (ED) for assessment. Misdiagnosis of concussion has been documented in children and likely impacts treatment and discharge instructions. This study aimed to examine diagnosis of concussion in a general adult population. METHODS: Patients >17years old presenting meeting the World Health Organization's definition of concussion were recruited in one academic (Hospital 1) and two community (Hospitals 2 and 3) EDs in a Canadian city. A physician questionnaire and patient interviews documented recommendations given by emergency physicians. Bi-variable comparisons are reported using chi-square tests, t-tests or Mann-Whitney tests, as appropriate. Multivariate analyses were performed using logistic regression methods. RESULTS: Overall, the study enrolled 250 patients. The median age was 35 (IQR: 23 to 49) and 52% were female. A variety of concussion causes were documented. Forty-one (16%) patients were not diagnosed with a concussion despite meeting criteria. Concussion diagnosis was less likely with a longer ED length of stay (OR=0.71; 95% CI: 0.60 to 0.83), presenting to the non-academic centers (Hospital 2: OR=0.21, 95% CI: 0.08 to 0.58; Hospital 3: OR=0.07, 95% CI: 0.02 to 0.24), or involvement in a motor vehicle collision (OR=0.11; 95% CI: 0.03 to 0.46). CONCLUSION: One in six patients with concussion signs and symptoms were misdiagnosed in the ED. Misdiagnosis was related to injury mechanism, length of stay, and enrolment site. Closer examination of institutional factors is needed to identify effective strategies to promote accurate diagnosis of concussion.

A Prospective Evaluation of the Influence of an Electronic Clinical Practice Guidelines on Concussion Patients' Future Activities and Outcomes.

BACKGROUND: Patients with mild traumatic brain injury or concussion commonly present to the emergency department for assessment; providing patients with information on usual symptoms and their progression may encourage faster recovery. OBJECTIVES: This study aimed to document the role of an electronic clinical practice guideline (eCPG) patient handout on concussion recovery in adult patients discharged from the hospital. METHODS: A prospective cohort study was carried out in 3 Canadian urban emergency departments. Adults (≥17 years of age) with a Glasgow Coma Scale score of 13 to 15 who sustained a concussion were recruited by on-site research assistants. Physician use of a concussion-specific eCPG was documented from physician and patient reports. Patient follow-up calls at 30 and 90 days documented return to work/school activities and patient symptoms. Multivariate analyses were performed using logistic regression methods. RESULTS: Overall, 250 patients were enrolled; the median age was 35 (interquartile range 23-49) and 52% were female. Approximately half (n = 119, 48%) of patients received the eCPG handout, and return to work/school recommendations varied. Symptoms persisted in 60% of patients at 30 days; patients in the eCPG group had fewer symptoms (odds ratio 0.57, 95% confidence interval 0.33-0.99). At 90 days, 40% of patients reported persistent symptoms, with no significant difference between groups. CONCLUSION: An eCPG handout improved patients' short-term outcomes; however, physician use and adherence to guideline recommendations was low. To further facilitate physician compliance and therefore patient recovery, barriers to use of the eCPG handout need to be identified and addressed.

Does Game Participation Impact Cognition and Symptoms in Elite Football Players?

OBJECTIVE: To measure neurocognitive functioning in college and professional football players after game participation. STUDY DESIGN: Retrospective, cross-sectional cohort design. PARTICIPANTS: Ninety-four male university and professional football players. INTERVENTION: All participants completed Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) testing at baseline, and either at postconcussion (group 1) or postgame (group 2) participation. MAIN OUTCOME MEASURES: Results from the 5 ImPACT composite scores (Verbal Memory, Visual Memory, Visual Motor Speed, Reaction Time and Impulse Control) and Total Symptom Score. RESULTS: Repeated-measures analysis of variance demonstrated a significant main effect for time (improvements) in 3 of 5 domains for the postconcussion group, but no improvements in the postgame group. The postconcussion group presented with significantly improved results on 4 of 5 ImPACT domains compared with the postgame group at the follow-up time interval. CONCLUSIONS: Participation in a football game with potential cumulative head contacts did not yield increased symptoms or cognitive impairment. However, the absence of improvement in cognitive functioning in noninjured football players, which was found in those players who were returned to play after an injury, may suggest that there is a measureable impact as a result of playing football.

Exploring minor hockey players' knowledge and attitudes toward concussion: implications for prevention.

OBJECTIVE: To evaluate minor hockey players' attitudes and knowledge about sport concussions. PARTICIPANTS: Male and female Pee Wee, Bantam, and Midget level players (n = 183) participating in minor hockey and a comparison group of non-hockey players (n = 57). DESIGN: Survey. MAIN MEASURES: Player knowledge and attitudes were evaluated with a standardized questionnaire developed for the purpose of this study. Descriptive statistics including cross-tabulations and proportion comparisons were used to report the data. RESULTS: Players had foundational knowledge about concussions; however, more than half underestimated the prevalence and more than 30% were unaware of return to play protocols. Although nearly all players knew what they "should" do when concussed, 33% did not follow recommendations. Players reported more concern and appreciation of the seriousness of concussion than non-players, but they tended to minimize their vulnerability. The most common and helpful information sources were parents, doctors, and coaches, and therefore knowledge translation efforts should target theses audiences. CONCLUSION: Young athletes continue to demonstrate gaps in their knowledge of concussions. In addition, attitudes toward concussion suggest a developmental trajectory with younger athletes being most likely to ignore current recommended guidelines.

A qualitative review of sports concussion education: prime time for evidence-based knowledge translation.

BACKGROUND: Educating athletes, coaches, parents and healthcare providers about concussion management is a public health priority. There is an abundance of information on sports concussions supported by position statements from governing sport and medical organisations. Yet surveys of athletes, parents, coaches and healthcare providers continue to identify multiple barriers to the successful management of sports concussion. To date, efforts to provide education using empirically sound methodologies are lacking. PURPOSE: To provide a comprehensive review of scientific research on concussion education efforts and make recommendations for enhancing these efforts. STUDY DESIGN: Qualitative literature review of sports concussion education. METHODS: Databases including PubMed, Sport Discus and MEDLINE were searched using standardised terms, alone and in combination, including 'concussion', 'sport', 'knowledge', 'education' and 'outcome'. RESULTS: Studies measuring the success of education interventions suggest that simply presenting available information may help to increase knowledge about concussions, but it does not produce long-term changes in behaviour among athletes. Currently, no empirical reviews have evaluated the success of commercially available sports concussion applications. The most successful education efforts have taken steps to ensure materials are user-friendly, interactive, utilise more than one modality to present information and are embedded in mandated training programmes or support legislation. Psychosocial theory-driven methods used to understand and improve 'buy in' from intended audiences have shown promise in changing behaviour. CONCLUSIONS: More deliberate and methodologically sound steps must be taken to optimise education and knowledge translation efforts in sports concussion.

Absence of differences between male and female adolescents with prior sport concussion.

OBJECTIVE: Sex differences following concussion are poorly understood. The purpose of this study was to examine whether male and female adolescent athletes with prior concussions differ regarding neurocognitive function and symptom reporting. SETTING: Community-based hockey teams. PARTICIPANTS: Participants included 615 elite hockey players 13 to 17 years old (mean = 15.5, 95% confidence interval [CI] = 15.4-15.6). There were 517 males and 98 females. Players with English as a second language, attention or learning problems, a concussion within 6 months of baseline, or suspected invalid test profiles were excluded from these analyses. DESIGN: Cross-sectional. MAIN MEASURE: Domain scores and symptom ratings from the ImPACT computerized battery. RESULTS: There were no significant neurocognitive differences between males and females with (F5,227 = 1.40, P = .227) or without (F5,376 = 1.33, P = 0.252) a prior history of concussion. Male and female athletes with a history of concussion reported higher raw symptom scores than those without a prior concussion; however, sex differences disappear when symptom scores are adjusted for known sex differences in controls (total score, F2,230 = 0.77, P = .46; Cohen d = 0.01 or domain scores (F4,227 = 1.52, P = .197; Cohen d = 0.07-0.18). CONCLUSIONS: Although those with prior concussions report more symptoms (but do not differ on neurocognition), this study does not support sex differences with cognition or symptoms in adolescent athletes with prior concussions.

Correction: Currie et al. Reality Check 2: The Cost-Effectiveness of Policy Disallowing Body Checking in Non-Elite 13- to 14-Year-Old Ice Hockey Players. Int. J. Environ. Res. Public Health 2021, 18, 6322.

There was an error in our original publication [...].

Safe2Play in youth ice hockey: injury profile and risk factors in a 5-year Canadian longitudinal cohort study.

INTRODUCTION: Ice hockey is a popular global sport with growing participation for boys and girls yet remains a high-risk sport for injury. While the evidence for some risk factors, such as bodychecking policy is well established, other risk factors such as player sex have been understudied. The objectives of this study were to examine factors associated with rates of game-related injury, game-related injury resulting in >7 days of time-loss, and practice-related injury in youth ice hockey. MATERIALS AND METHODS: Safe2Play was a five-year prospective cohort study (2013-2018). All injuries were identified using validated injury surveillance methodology. Multilevel Poisson regression (adjusting for cluster by team and including multiple imputation of missing covariates) was used to estimate incidence rate ratios (IRRs) for player sex, age group, bodychecking policy, year of play, level of play, weight, previous injury within last 12 months, previous lifetime concussion history, and position. RESULTS: A total of 4418 male and female ice hockey players (representing 6584 player-seasons) participating in under-13 (ages 11-12), under-15 (ages 13-14) and under-18 (ages 15-17) age groups were recruited. There were 1184 game-related and 182 practice-related injuries. Factors associated with game-related injury included female sex (IRR = 1.57; 95% CI: 1.18-2.08), previous injury (IRR = 1.46; 95% CI: 1.26-1.70) and lifetime concussion history (IRR = 1.41; 95% CI: 1.23-1.62). Goaltenders had a lower rate of injury (IRR = 0.54; 95% CI: 0.40-0.72) relative to forwards, as did players exposed to policy disallowing bodychecking in games (IRR = 0.44; 95% CI: 0.35-0.55). Female sex (IRR = 1.90; 95% CI: 1.10-3.28) and lifetime concussion history were also significantly associated with practice-related injury (IRR = 1.53; 95% CI: 1.08-2.18). CONCLUSIONS: Based on data from a large 5-year Canadian youth ice hockey longitudinal cohort, several factors associated with injury were identified. Future injury prevention strategies should consider age, sex, previous concussion and injury history, and body checking leagues. Future research in female youth ice hockey including female-only leagues should be a priority to inform prevention strategies in this understudied population.

Symptom Exacerbation and Adverse Events during a Randomized Trial of Early-stage Concussion Rehabilitation.

CONTEXT: Few studies utilize randomized clinical trials (RCT) to quantify clinical intervention safety of rehabilitation after sport-related concussion across sport levels. OBJECTIVE: Describe symptom exacerbation and adverse events (AEs) associated with two concussion rehabilitation interventions. DESIGN: Cluster Randomized Controlled Trial (XXX). SETTING: Sports medicine clinic and field settings. PARTICIPANTS: The RCT enrolled 251 concussed athletes (median age=20 years; female n=48) across 28 sites from New Zealand professional rugby (n=31), Canadian professional football (n=52), United States (U.S.)/Canadian colleges (n=128) and U.S. high schools (n=40). INTERVENTIONS: Two medically supervised interventions: 1) Enhanced Graded Exertion (EGE): international return to sport strategy and sport specific activities only (EGE-only n=119) and 2) Multidimensional Rehabilitation (MDR) followed by EGE: early symptom-directed exercises once symptoms were stable, followed by EGE after symptoms resolved (MDR+EGE n=132). MAIN OUTCOME MEASURES: Primary outcomes were intrasession total symptom severity score exacerbation and significant intersession (increase 10+ severity points) sustained total symptom severity exacerbation, each measured with a Postconcussion Symptom Scale (132 total severity points on scale). Reported AEs were also described. Activity-based rehabilitation sessions (n=1437) were the primary analysis unit. Frequencies, proportions, medians, and Interquartile Ranges (IQRs) were calculated for outcomes by treatment group. RESULTS: The 251 post-injury participants completed 1437 (MDR+EGE=819, EGE-only=618) activity-based intervention sessions. A total of 110 and 105 participants contributed data (those missing had no documented session data) to at least 1 activity-based session in the MDR+EGE and EGE-only arms respectively. Intrasession symptom exacerbations were equivilantly low in MDR+EGE and EGE-only arms (MDR+EGE: 16.7%, 95% CI:14.1%,19.1%; EGE-only: 15.7%, 95% CI: 12.8%,18.6%). In total, 9/819 MDR+EGE sessions (0.9%) and 1/618 EGE-only sessions (0.2%) resulted in a pre- to post-session symptom exacerbation beyond a 10+ severity point increase; 8/9 resolved to <10 points by the next session. Two study-related AEs (1 in each arm) were reported. CONCLUSIONS: Participants in MDR+EGE and EGE-only activities reported equivalently low rates of symptom exacerbation.

Sport concussion knowledge base, clinical practises and needs for continuing medical education: a survey of family physicians and cross-border comparison.

CONTEXT: Evolving concussion diagnosis/management tools and guidelines make Knowledge Transfer and Exchange (KTE) to practitioners challenging. OBJECTIVE: Identify sports concussion knowledge base and practise patterns in two family physician populations; explore current/preferred methods of KTE. DESIGN: A cross-sectional study. SETTING: Family physicians in Alberta, Canada (CAN) and North/South Dakota, USA. PARTICIPANTS: CAN physicians were recruited by mail: 2.5% response rate (80/3154); US physicians through a database: 20% response rate (109/545). INTERVENTION/INSTRUMENT: Online survey. MAIN AND SECONDARY OUTCOME MEASURES: Diagnosis/management strategies for concussions, and current/preferred KTE. RESULTS: Main reported aetiologies: sports/recreation (52.5% CAN); organised sports (76.5% US). Most physicians used clinical examination (93.8% CAN, 88.1% US); far fewer used the Sport Concussion Assessment Tool (SCAT1/SCAT2) and balance testing. More US physicians initially used concussion-grading scales (26.7% vs 8.8% CAN, p=0.002); computerised neurocognitive testing (19.8% vs 1.3% CAN; p<0.001) and Standardised Assessment of Concussion (SAC) (21.8% vs 7.5% CAN; p=0.008). Most prescribed physical rest (83.8% CAN, 75.5% US), while fewer recommended cognitive rest (47.5% CAN, 28.4% US; p=0.008). Return-to-play decisions were based primarily on clinical examination (89.1% US, 73.8% CAN; p=0.007); US physicians relied more on neurocognitive testing (29.7% vs 5.0% CAN; p<0.001) and recognised guidelines (63.4% vs 23.8% CAN; p<0.001). One-third of Canadian physicians received KTE from colleagues, websites and medical school training. Leading KTE preferences included Continuing Medical Education (CME) courses and online CME. CONCLUSIONS: Existing published recommendations regarding diagnosis/management of concussion are not always translated into practise, particularly the recommendation for cognitive rest; predicating enhanced, innovative CME initiatives.