Use of Time-to-Event Analyses to Identify Concussion Prevention Opportunities During Athletic Seasons: Findings from The Ivy League-B1G Ten Epidemiology of Concussion Study

Use of Time-to-Event Analyses to Identify Concussion Prevention Opportunities During Athletic Seasons: Findings from The Ivy League-B1G Ten Epidemiology of Concussion Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Use of Time-to-Event Analyses to Identify Concussion Prevention Opportunities During Athletic Seasons: Findings from The Ivy League-B1G Ten Epidemiology of Concussion Study Sydney Sturino, Abigail C. Bretzin, Christopher Knaub, Douglas J. Wiebe This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7633996/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: We aim to create concussion prevention opportunities using time-to-event analytic approaches. This study investigates the timing of sport-related concussion (SRC) incidence across a full academic year. Method: In a prospective cohort study, The Ivy League-Big Ten Epidemiology of Concussion Study, we examined SRCs within contact and collision sports across the two conferences during 2023–2024 academic year. Survival analyses, using academic year start and end dates and dates of injury, investigated the timing of SRC onset in each sport. Kaplan-Meier curves and Cox proportional hazard models compared instantaneous risks using hazard ratios (HR) between men’s and women’s teams with 95% confidence intervals (CI). Results: Out of 4,555 contact and collision athletes in fall (n = 2,888, 63.4%), winter (n = 826, 18,1%), and spring (n = 841, 18.5%) sports, 369 SRCs occurred; 13 athletes sustained repeat SRCs during the academic year. Football (n = 155, 42.0%) and women’s soccer (n = 37, 10.0%) accounted for the largest percentages of SRCs. Across all sports, by 30 days 98.9%, 60 days 97.6%, 90 days 95.9%, and by end of the academic year 92.3% were free from concussion, respectively. Within-sport, SRC proportions were highest during weeks 2 and 15 in football, the middle of the season (week 6) in sprint football, the end of the fall season (week 12) in women’s rugby, and early in the season (week 13) in women’s ice hockey. By the end of the academic year the proportion free from SRC was 81.7% (95%CI: 72.3–88.2) to 95.6% (95%CI: 92.5–97.4). There was no association in SRC hazard between men and women overall, (HR:1.1, 95%CI:0.9,1.4), ice hockey (HR:1.3, 95%CI: 0.7, 2.6), soccer (HR:0.5, 95%CI:0.3,1.0), and lacrosse (HR:1.0, 95%CI:0.6,1.8). Conclusion: This is the first study examining SRC risk utilizing repeated time-to-event analyses to identify notable timeframes of SRC incidence. With this method, and a collaborative stakeholder-engaged prospective cohort study, it is possible to strategically direct SRC prevention efforts and advance analytic approaches, which was identified as a priority for future research at the most recent Concussion in Sport Group (CISG) meeting. Figures Figure 1 Figure 2 Figure 3 Background Collegiate sport participation continues to grow, with over 500,000 athletes at-risk for injury annually.( 1 ) The National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) reported that overall injury rates range from 4.9 per 1,000 athletic exposures (AEs) in Men’s Lacrosse to 9.3 per 1,000 AEs in football, with variability across men’s and women’s sports.( 2 – 10 ) Early research in collegiate athletic settings described that approximately 9.8% of game and 12.8% of practice injuries occur to the head and neck.( 11 ) Sport-related concussions (SRC) are a complicated and common head and neck injury, accounting for 5.2%, in men’s soccer, to 11.9%, in women’s ice hockey, of all injuries, depending on the sport.( 2 – 10 ) Further, preliminary estimates from the NCAA-ISP suggest an overall SRC rate of 4.5 per 10,000 athlete exposures between the 2009/10 through 2013/14 academic years.( 12 ) More recently, Chandran et al.( 13 ) identified an overall SRC rate of 4.1 per 10,000 AE across all sports from 2014/15 through 2018/19. Importantly, this research identifies SRCs as prevalent injuries among contact and collision sports; yet, these methodologies don’t account for the temporality of SRC across an athletic season, which could inform the development of targeted prevention interventions. Using a prospective cohort design in the Ivy League-Big Ten Epidemiology of Concussion Study, Putukian et al.( 14 ) reported that the majority (94.0%) of SRCs in collegiate athletics occurred during the regular season and 6% of SRCs occurred during the preseason across all sports. Separately, using data from the NCAA-Department of Defense (DoD) Concussion Assessment, Research and Education (CARE) Consortium, Broglio et al.( 15 ) reported SRC rates in Division I football were similar between the preseason and spring seasons, and both were higher than fall SRC rates. In contrast, when using the Head Impact Telemetry System (HITS), a program used to record head impact exposure during helmeted football play, Stemper et al.( 16 ) reported that the average concussion incidence, the total number of concussions over the number of consented and enrolled athletes, in Division I football was higher during the regular (3.5%) football season than the preseason (3.1%) and was the highest in 2015 (8.5%) during the five-year study period from 2015 through 2019. Separately, in high school football, Bretzin et al.( 17 ) reported the frequency of SRCs occurring each week throughout the season, highlighting that the highest percentage of practice-related concussions occurred in the first two weeks before the first competition, and the highest percentage of competition-related concussions occurred in the middle of the athletic season (i.e., weeks 5–9). To compliment these studies aimed at identifying timeframes of heightened SRC occurrence, advancing analytic approaches may prompt prevention efforts by understanding time-specific contextual factors that highlight key times during athletic seasons of which SRCs occur. As an example, in 2018, the NCAA reduced the number of preseason on-field practice events based on epidemiologic evidence that demonstrated SRCs were common during these activities and this period during the season.( 18 ) Importantly, most research on SRC occurrence is limited to football, warranting research studying the temporality of SRC incidence in additional contact and collision sports. Further, research and awareness is growing regarding sex and gender-based differences in SRC incidence. For example, Covassin et al.( 19 ) reported that women in comparable sports (i.e., soccer, lacrosse, ice hockey, etc.) had a 1.4 times greater incidence of reported SRC relative to their men counterparts in the same sports. More recently Chandran et al.( 13 ) also reported that overall SRC rates were higher in women’s sports relative to men’s sports in soccer, basketball, and softball relative to baseball. Similarly, Bretzin et al.( 20 ) found that girls’ high school soccer teams demonstrated a 1.8 times greater risk of documented SRC and took a median of 2 days longer to return to play compared to boys’ soccer. To extend the existing research, analytic approaches using time-to-event analyses may improve our understanding of the timing of when women sustain SRCs throughout an academic year and enable novel comparisons with men in the same sports. In addition to informing SRC prevention opportunities, improving methods to study the temporality of concussion can be applied in additional research contexts; for example, investigating repeated musculoskeletal (MSK) injuries across an athletic season, especially after SRC. In recent work by Oldham et al.( 21 ), the authors reported approximately 28% of collegiate athletes sustained acute MSK injury within six months following a diagnosed concussion, with higher risk reported among collision sport athletes. Similarly, Brooks et al.( 22 ) found that collegiate athletes across seven sports had 2.5 times the odds of sustaining a lower extremity MSK injury within 90 days after sustaining an SRC than athletes without a recent SRC. Incorporating time-to-event analyses in future studies may yield a better understanding of when athletes are at risk for subsequent injuries while appropriately accounting for time at risk. With this as our motivation, we aim to advance concussion prevention opportunities by incorporating time-to-event analyses in a large ongoing prospective cohort study of SRC in collegiate athletics. The overall purpose of this analysis was to describe the timing of SRC in contact and collision sports across a full academic year. We also compared the timing of SRC between men and women on comparable teams, hypothesizing the rate of SRC would be higher in women relative to men based on prior literature. Methods Study Design We conducted a prospective cohort study using the Ivy League-Big Ten Epidemiology of Concussion Study.( 14 ) The [BLINDED FOR REVIEW] University Institutional Review Board (IRB) served as the central IRB, with reliance agreements and/or site-IRB agreements depending on the participating university. All athletes provided informed consent prior to participation in the study. Data sources We extracted data from contact and collision sports from the 2023–2024 academic season, examining SRC within two Division I collegiate athletic conferences. Methodology from the Ivy League-Big Ten Epidemiology of Concussion Study was described previously.( 14 ) Study Population The study population included 4,555 college-age athletes participating in contact and collision sports. Operational Definitions Sport-Related Concussion . This study used the definition of SRC from the Concussion in Sport Group 2022 Amsterdam International Consensus Conference on Concussion in Sport. ( 23 ) A concussion is defined as a traumatic brain injury caused by a blow to the head, neck, or body resulting in an impulsive force being transmitted to the brain that occurs in sports and exercise-related activities. This injury presents signs and symptoms that cannot be explained by any other cause. Concussions are recognized and/or reported to sports medicine teams across each athletics program. Team physicians in each program conduct a multifaceted assessment aligning with current consensus and practice guidelines to make concussion diagnoses. Diagnosed concussions, characteristics of the injured athletes, and recovery information are reported by trained research assistants at participating campuses. For the purposes of this study, only SRC were included in analyses. Academic Year . The term academic year was defined as the period starting on August 1st, 2023, through the follow-up period of June 30th, 2024. Contact and Collision Sports . This analysis comprised contact and collision sports which included men’s and women’s lacrosse, soccer, wrestling, rugby, and ice hockey, men’s football and sprint football, and women’s field hockey and varsity rugby. Men’s rugby was not included in this study, as men’s teams at participating campuses participate at the club, not varsity level. Concussion monitoring. Figure 1 presents examples of the identification of SRC onset as well as repeat SRC among the same athletes during the academic year were identified over the follow-up period. The figure specifically displays the following scenarios: following an athlete from the start of the season through the end, with no diagnosed SRC; following an athlete from the start of the season to first SRC and from return to play to end of academic year; following athlete from the start of the season to first SRC, return to play to second SRC, and return to play to the end of the academic year; and following an athlete from the start of the season to SRC without returning to play. Statistical analysis We reported descriptive statistics using medians and interquartile ranges for continuous variables, and frequencies with percentages for categorical variables. We used time-to-event analyses allowing for repeat events (i.e., athletes that sustained multiple SRCs during the same academic year) to describe the temporality of SRC risk across the academic year. With an Andersen-Gill model for analyzing time-to-repeated events, we completed independent Kaplan-Meier Survival to display the proportion of athletes without a diagnosed SRC throughout the academic year within each sport. We estimated survival functions to report the proportion of athletes without a diagnosed SRC by 30 days, 60 days, 90 days, and the end of the academic year. In addition to Kaplan-Meier Survival plots, we present the percentage of all diagnosed SRC that occurred each week during the academic year. Kaplan-Meier curves and percentage plots are presented in the same graph with defined axes. We also compared the instantaneous rate between men’s and women’s teams in the sport (HR) using Cox proportional hazard models. We used Schoenfeld residual plots to evaluate the proportional hazards assumption. We determined significance if the 95% confidence interval (CI) excluded one. All analyses were completed in STATA (18.2, StataCorp LLC, College Station, Texas). Results Out of the 4,555 athletes (male: n = 3,168, 69.6%, female: n = 1387, 30.5%) that were included in contact and collision sports during the 2023/24 academic year, 369 concussions occurred (Table 1 ). There were 356 (7.82%) athletes that sustained one SRC and 13 (0.3%) athletes that sustained more than one SRC during the academic year. Table 2 presents the percentage of SRC by each men’s and women’s sport. Overall, 281 (76.2%) men and 88 (23.9%) women sustained an SRC. Almost half (n = 178, 48.2%) of the SRC cases did not have a history of previous concussion(s). Across all sports, practice (n = 192, 52.2%) and competition (n = 150, 41.0%) accounted for the highest percentages of SRC, respectively. Freshman (n = 91, 24.8%) and Sophomore (n = 91, 24.8%) athletes accounted for almost half of all SRCs. Table 1 Characteristics of Student-Athletes during 2023/24 Academic Year Demographics n % Gender Men 3168 69.6 Women 1387 30.5 Sport Football 1692 37.2 Men's Lacrosse 471 10.3 Women's Soccer 432 9.5 Men's Wrestling 399 8.8 Women's Lacrosse 370 8.1 Men's Soccer 295 6.5 Field Hockey 284 6.2 Men's Ice Hockey 219 4.8 Women's Ice Hockey 182 4.0 Women's Rugby 93 2.0 Sprint Football 92 2.0 Women's Wrestling 26 0.6 Percent of Student-Athletes Sustaining Concussion(s) during academic year 0 4,186 91.9 1 356 7.8 2 13 0.3 Table 2 Characteristics of Sport-Related Concussion Cases* during the 2023/24 Academic Year Diagnosed Sport-Related Concussion Cases n % Gender Men 281 76.2 Women 88 23.9 Sport Football 155 42.0 Women's Soccer 37 10.0 Men's Wrestling 29 7.9 Men's Lacrosse 26 7.1 Men's Ice Hockey 24 6.5 Women's Lacrosse 20 5.4 Women's Ice Hockey 16 4.3 Sprint Football 16 4.3 Women's Rugby 16 4.3 Field Hockey 15 4.1 Men's Soccer 15 4.1 Women's Wrestling 0 0 Previous Concussion History 0 178 48.2 1 101 27.4 2 45 12.2 3+ 38 10.3 Missing 7 1.9 Activity Type Practice 192 52.2 Competition 150 41.0 Scrimmage 19 5.2 Strength and Conditioning 3 0.8 Sport-specific unsupervised activity 2 0.6 Other 1 0.3 Class year Freshman 91 24.8 Sophomore 91 24.8 Junior 89 24.3 Senior 72 19.6 Fifth Year 15 4.1 Sixth Year 1 0.3 Seventh Year 8 2.2 *Athletes with multiple SRC in one academic year were reported twice SRC Timing During Academic Year Overall Table 3 presents the percentage of athletes without a diagnosed SRC in 30-day time intervals across the academic year. Across all sports, by 30 days 98.9%, 60 days 97.6%, 90 days 95.9%, and by end of the academic year 92.3% of athletes were free from SRC, respectively. In men, by 30 days 98.6%, 60 days 97.39%, 90 days 95.8%, and by the end of academic year 92.0% of athletes were free from SRC, respectively. In women, by 30 days 99.4%, 60 days 98.3%, 90 days 96.1%, and by the end of academic year 92.6% of athletes were free from SRC, respectively. Across all sports, there was no association in the instantaneous rate of SRC between men and women (HR:1.09, 95% CI: 0.87, 1.37). Table 3 Survival Estimates Describing the Percent of Student-Athletes Free from Diagnosed Concussion at Several Timepoints during Academic Year and Comparisons between sports with Men's and Women's Teams Sport Percent (%) of Student-Athletes Free from Sport-Related Concussion Comparable Sports 30 days 95% CI 60 days 95% CI 90 days 95% CI Academic Year End 95% CI Hazard Ratio 95% CI Combined 98.9 (98.5, 99.1) 97.6 (97.1, 98.0) 95.9 (95.3, 96.4) 92.3 (91.5, 93.0) Men 98.6 (98.2, 99.0) 97.3 (96.7, 97.8) 95.8 (95.0, 96.4) 92.0 (91.0, 93.0) 1.1 (0.9, 1.4) Women 99.4 (98.8, 99.7) 98.3 (97.4, 98.8) 96.1 (94.9, 97.0) 92.6 (91.0, 93.0) Fall Sports Women's Rugby 98.9 (92.5, 99.9) 96.8 (90.3, 98.9) 88.4 (79.9, 93.4) 80.4 (71.0, 87.0) Sprint Football 96.7 (90.2, 98.9) 88.1 (79.6, 93.2) 86.1 (77.3, 91.7) 84.1 (75.1, 90.1) Football 97.7 (96.9, 98.3) 95.9 (94.8, 96.7) 94.2 (93.0, 95.2) 91.2 (89.8, 92.4) Men's Soccer 100.0 -- 100.0 -- 98.6 (96.4, 99.5) 95.6 (92.6, 97.5) 0.5 (0.3, 1.0) Women's Soccer 99.1 (97.5, 99.7) 97.9 (96.0, 98.9) 95.6 (93.3, 97.2) 92.1 (89.2, 94.3) Field Hockey 98.6 (96.3, 99.5) 98.6 (96.3, 99.5) 96.9 (94.1, 98.4) 94.8 (91.5, 96.8) Winter Sports Men's Ice Hockey 99.5 (96.8, 99.9) 98.6 (95.8, 99.6) 96.4 (92.9, 98.2) 89.5 (84.7, 92.8) 1.3 (0.7, 2.6) Women's Ice Hockey 100.0 -- 98.4 (95.0, 99.5) 95.7 (91.5, 97.8) 92.0 (87.1, 95.1) Men's Wrestling 100.0 -- 100.0 -- 99.0 (97.4, 99.6) 93.2 (90.2, 95.2) Women's Wrestling 100.0 -- 100.0 -- 100.0 -- 100.0 -- Spring Sports Men's Lacrosse 100.0 -- 99.8 (98.5, 99.9) 98.7 (97.2, 99.4) 94.8 (92.4, 96.4) 1.0 (0.6, 1.8) Women's Lacrosse 100.0 -- 98.7 (96.8, 99.4) 97.9 (95.7, 98.9) 94.7 (91.9, 96.5) SRC Timing During Academic Year for Individual Sports Independent Kaplan-Meier curves present the proportion of athletes without a diagnosed SRC throughout the academic year within each sport. Figure 2 presents fall sports, and Fig. 3 presents winter and spring sports. Football. The Kaplan-Meier curve revealed diagnosed SRC in football (n = 155) occurred early in the academic year prior to the first game of the season. The proportion of athletes sustaining a SRC consistently increased during the season, then paused throughout winter months. Diagnosed SRCs occurred again in weeks prior to and during the spring season scrimmages. In football, weeks 2 (9.0%) and 15 (9.0%) accounted for the highest percentages of diagnosed SRC. Weeks 1, 3, and 10 accounted for 7.1% of SRCs, respectively. Spring football in weeks 36 and 37 accounted for 5.2% and 3.2% of diagnosed SRCs, respectively. Overall, in football, by 30 days 97.7%, 60 days 95.9%, 90 days 94.2%, and end of the academic year 91.2% of athletes were free from SRC. Sprint Football. The Kaplan-Meier curve revealed no SRC occurred during pre-season in sprint football. Whereas SRC occurred throughout the regular season with the highest percentage of the total (n = 16) concussions occurring during week 6 (31.2%), and weeks 4, 7, 12, and 14 each accounting for 12.5% of SRCs, respectively. By 30 days 96.7%, 60 days 88.1%, 90 days 86.1%, and end of the academic year 84.1% of athletes were free from SRC. Field Hockey . SRCs in field hockey (n = 15) occurred early after the start (week 4, 20.0%) and midpoint (week 11, 13.3%) of the fall season, and at the start of the spring season (week 31, 20.0%). In field hockey, 30 days 98.6%, 60 days, 90 days 96.9%, and end of the academic year 94.8% of athletes were free from SRC. Women’s Rugby . In women’s rugby, SRC (n = 19) occurred during pre-season and throughout duration of the fall season, with week 12 observably at the highest percentage (26.3%) of SRCs. Then SRC again occurred prior to the start of the spring season in February through May. Week 35 during the spring season accounted for 10.5% of SRCs. By 30 days 98.9%, 60 days 96.8%, 90 days 88.4%, and end of the academic year 80.4% of athletes were free from SRC. Soccer. In men’s soccer, SRC (n = 14) first occurred in October, mid-way through the fall season, prior to the start of the spring season, and throughout the spring season. Weeks 12 and 31 observably had the highest percentages (15.4%) of diagnosed SRCs, respectively. By 30 days 100%, 60 days 100%, 90 days 98.6%, and end of the academic year 95.6% of athletes were free from SRC. In women’s soccer, SRCs (n = 37) occurred during pre-season, throughout the regular season, immediately following the regular season, and during the spring season. Weeks 9 and 12 (11.4%) accounted for the highest percentage of diagnosed SRC, respectively. By 30 days 99.1%, 60 days 97.9%, 90 days 95.6%, and by the end of the academic year 92.1% of athletes were free from SRC. There was no significant difference in the instantaneous rate of SRC between men’s and women’s soccer (HR: 0.5, 95% CI: 0.3, 1.0). Ice Hockey. In men’s hockey, SRCs (n = 24) occurred throughout the pre-season and duration of the regular season. Week 13 observably had the highest percentage (12.5%) of diagnosed SRC. While diagnosed SRCs steadily occurred throughout later weeks toward the end of the competitive season. At 30 days 99.5%, 60 days 98.6%, 90 days 96.4%, and by the end of the academic year 89.5% of athletes in men’s hockey were free from SRC. In women’s ice hockey, SRCs (n = 16) occurred during pre-season with the majoring occurring during the early weeks of the regular season. Week 13 (31.2%) observably had the highest percentage of diagnosed SRC, followed by weeks 16 and 18 accounting for 12.5%, respectively. By 30 days 100%, 60 days 98.4%, 90 days 95.7%, and at the end of the academic year 92.0% of athletes were free from SRC. There was no significant difference in the instantaneous rate of SRC between men’s in women’s ice hockey (HR: 1.3, 95% CI: 0.7, 2.6). Wrestling. In wrestling (n = 28) SRC began to occur at the start of the regular season. The highest percents of SRCs were observed in the middle of the season during weeks 16 and 22 each 14.3%, respectively. By 30 days 100%, 60 days 100%, 90 days 99.0%, and at the end of the academic year 93.2% of athletes were free from SRC. For the 2023/24 season, women’s wrestling had one team of 26 athletes, where no SRCs were reported. Lacrosse . In men’s lacrosse, no SRCs occurred prior to the start of the fall season. SRC (n = 26) did occur throughout the fall season, yet the highest percentages of SRC were observed early in the spring season during weeks 27 and 29 each at 11.5%, respectively. By 30 days 100%, 60 days 99.8%, 90 days 98.7%, and end of the academic year 94.8% of athletes were free from SRC. In women’s lacrosse no SRCs occurred prior to the start of the fall season. The highest percentages of SRCs (n = 26) were observed during weeks 6, 10, and 14 each accounting for 15.0%, respectively. The highest percentage of SRCs during the spring season was 10.0% during week 36. By 30 days 100%, 60 days 98.7%, 90 days 97.9%, and end of the academic year 94.7% of athletes in women’s lacrosse were free from SRC. The instantaneous rate of SRC did not differ between men’s and women’s lacrosse (HR: 1.0, 95% CI: 0.6, 1.8). Discussion This is the first study, to date, approaching the study of SRC incidence with time-to-event analyses, providing insights into the timing of SRC occurrence in contact and collision sports across a full academic year. A total of 369 SRCs occurred among 4,555 athletes, and by the end of the academic year, the proportion of athletes free from SRC ranged from 80.4% in women’s rugby and 84.1% in sprint football to 95.6% in men’s soccer. These results are consistent with previous research regarding general timing; however, this study extends prior research that provides the crude frequency of how often events happen relative to opportunities for them to happen (i.e., SRC per AEs). In this study, our time-to-event analyses brings novel attention to the distribution of SRC risk over time across and within sports. These methods should serve as a model that can be applied in future research across more years, additional sports, and comprehensive injury surveillance across all injury categories. Previous research reporting on the incidence or prevalence of SRCs through AE over the course of an athletic season, or academic year documents a crude frequency of injury occurrence relative to at-risk time,( 2 – 14 , 19 ) and to date, often describes the general timing of SRCs based on the segmental parts of the season (e.g., pre-season, regular season, post-season).( 15 – 17 , 24 ) Furthermore, many of these details are limited to football,( 6 , 15 – 18 , 24 ) despite growing evidence of high or equivalent SRC incidence among additional collegiate contact and collision sports. In the present study, we reported on overall rates plus the timing of SRCs over the course of an academic year, in multiple contact and collision sports. We identified a range of 4.4% to 19.6% of athletes sustained a SRC during the academic year, depending on the sport. Prior research shows that women consistently exhibit higher SRC rates than men in comparable sports.( 17 ) In the current study, when accounting for the proportion and timing of SRC, we found no difference in the instantaneous rate of SRC between men’s and women’s lacrosse. Prior research using frequency of injury relative to exposure time reported that men’s lacrosse exhibited higher SRC rates than women’s lacrosse;( 19 ) in contrast more recently, Chandran et al.( 13 ) did not include lacrosse when comparing injury rates in men’s and women’s lacrosse. Further, Bretzin et al. reported SRC clinical incidence among high school sports reporting earlier years boys’ lacrosse had higher rates and in more recent years during the study period girls’ lacrosse demonstrated higher rates. Together, these results paired with 5.2% of men’s and 5.3% of women’s lacrosse athletes sustaining a concussion by the end of the academic year in the present study suggest SRC injuries are prevalent in lacrosse, warranting continued research combining collaborated efforts between investigators, coaches, and policy makers to enhance safe sport participation among collegiate lacrosse athletes. Despite non-significant findings, in the present study men’s ice hockey had a 30% higher hazard of SRC than women’s ice hockey, and men’s soccer players had a 46% lower hazard of diagnosed SRC than women’s soccer players. These results from a one-year study period suggest that there may be differences in the instantaneous rate of SRCs in various sports between men’s and women’s teams. Prior work in ice hockey is inconsistent, with early findings demonstrating higher rates in men’s relative to women’s ice hockey,( 19 ) and no differences between men and women in more recent years.( 13 ) In soccer, akin to prior research,( 13 , 19 , 20 ) our study found a trend for significance as athletes in women’s soccer sustained more SRCs than in men’s. In addition, this study extends the findings of prior work as we demonstrated that SRC injuries for women started early in the fall season with an observably steeper slope than men, resulting in 7.9% of women and 4.4% of men with a diagnosed SRC by the end of the academic year inclusive of both fall and spring seasons in soccer. Additional years of data in future analyses might yield significant results more closely aligning with prior research. Similarly, more research is warranted to study SRC incidence in women’s wrestling as it grows in popularity. In the current analyses, we were limited to one team with 26 women participating at the NCAA varsity level, and no concussions were reported. Unsurprisingly, football athletes experienced most of their SRCs within the first 60 days, accounting for 45.8% of all football SRCs. Our study demonstrated that 24.6% of SRC occurred during the first four weeks, and 62.7% occurred between week 5 and the last regular season game; while prior research shows that most SRC in football occur in the preseason.( 15 ) We also found that approximately half of the SRCs occurred during practice (52.19%). There is contention in previous literature about where SRCs occur most frequently, practice or competition, as Zuckerman et al.( 12 ) reported a higher proportion of SRCs occurred during competition, while McCrea et al.( 24 ) found that more SRCs were obtained during practice in football. Notably, at risk time is often higher in practice verses competition, as a greater number of athletes participate in more hours of practice relative to competition motivating prevention initiatives that limit head repetitive neurotrauma during practice situations.( 18 ) Nonetheless, utilizing time-to-event analysis we can identify the specific periods that athletes are at heightened risk for SRC during the athletic season, share these findings with key stakeholders (e.g., coaches, sports medicine clinicians, athletic directors, policy makers), and collaboratively initiate and test the effectiveness of prevention activities, as successfully demonstrated within our study infrastructure.( 25 ) In addition to an application of time-to-event analyses, this study provides a novel contribution as one of the first to document the epidemiology of SRC within sprint football, which exhibited one of the highest percentages of athletes with a SRC by the end of the season. In sprint football, approximately 15.9% of athletes sustained an SRC by the end of their season. Most concussions occurred within the first 60 days of the start of the season, accounting for 68.8% of all sprint football concussions. Despite its foundation as a sport in the early 1930’s, research investigating SRC, and overall injury, in sprint football is limited. Sprint football is currently underway at two of the campuses participating in the present study, with a total of 92 sprint football athletes at risk for concussion in our study period. Existing research for the epidemiology of injury within the sport include a study by D’Alonzo et al.( 26 ) who combined sprint football with additional high-contact sports to compare recovery outcomes between men and women at different sport participation contact levels. However, such methodologies do not enable understanding of SRC recovery characteristics among sprint football athletes uniquely. Similarly, Wiebe and colleagues( 27 ) studied the stepwise return to sport progression among contact athletes with SRC, of which 3% of the sample included sprint football athletes; however, the authors did not report sport-specific findings. Separately, in a report of SRC recovery among collegiate athletes, Bretzin and colleagues( 28 ) identified sprint football accounted for 4.1% of SRC among men, and documented between 30–40% of sprint football athletes had a previous history of concussion. Sport-specific nuances within sprint football parallel those observed in wrestling, with a strict 178-pound weight limit for sprint football and weigh-ins occurring 2–4 days before a game. Thus, sprint football athletes may also use rapid weight cutting measures, which are currently understood to be associated with concussion symptoms and dehydration.( 29 ) However, more research is needed in this area. Separately, mechanisms of injury and SRC injury risk may be different than traditional American football, with smaller athletes and faster, more dynamic play, sprint football defenses rely on speed and execution rather than traditional football strategies. Taken together, these findings should motivate further stakeholder-engaged research and drive the initiation and evaluation of prevention initiatives in underrepresented sports. Women’s rugby demonstrated the highest percentage (19.6%) of athletes sustaining SRC by the end of the academic year, overall. Women’s rugby is comprised of two seasons: 7’s during the fall and 15’s during the spring. Over half (52.7%) of SRC occurred during fall 7’s, with the highest percentage at the end of the fall season (26.2%). Each season represents a different number of athletes on the field during game play, while using the same field dimensions (i.e., 100x70 meters). Also, the two seasons hold different game durations, as 7s have two 7-minute halves requiring repeated high-intensity sprints often with multiple matches played in one day, and 15s has two 40-minute halves requiring endurance, pacing, and sustained physical contests. Thus, women’s rugby 7s and 15s differ in player numbers, game duration, and style of play, resulting in distinct physical demands, technical requirements, and potentially injury risks. With increasing attention to the epidemiology of SRC in women’s rugby,( 14 , 30 – 37 ) our findings and study infrastructure highlight the importance of stakeholder-engaged research and support the initiation and evaluation of prevention initiatives in collegiate women’s rugby. By studying both 7s and 15s, our study provides a framework for applying these analytic methods in future injury research. Like rugby, football, lacrosse, field hockey, and soccer each have multiple seasons with competitive events at the collegiate level. Our findings demonstrate that SRCs occur across both periods, with a resurgence of injury within each sport. This suggests that SRC risk at the collegiate level is not solely restricted to the formal competitive season and can emerge during off-season, or second season activities. Competitive football play mainly occurs during the fall season, which we observed had the most SRC. The spring season yielded a lower percentage of SRCs; however, we observed an increase in SRC particularly around the spring season scrimmage. Recent discourse in collegiate athletics has highlighted a movement toward eliminating the spring scrimmage game, which could influence injury incidence. Additionally, with the recent addition of the NCAA transfer portal, programs may change the shape and design of spring practices and conditioning for the next competitive season, potentially impacting SRC risk. Separately, we observed higher rates for lacrosse during the spring competitive season but also found that SRCs occur during the shorter fall season. In field hockey, we observed most SRC within the fall season, which is the primary competitive with a longer schedule while the spring season is focused on skill development. There is a similar structure in soccer, and our data displayed the majority of SRC were sustained during the fall, while we observed an earlier frequency of injury in the spring season in men relative to women. Together, this study provided a novel opportunity to apply an analytic method that captures the distribution of injury risk across the year in contact and collision sports. This approach revealed sport-specific nuances and highlights the potential for continued research. With additional years of data and the inclusion of more sports, we aim to share these findings with stakeholder groups to inform, plan, implement, and evaluate targeted prevention strategies that promote safe sport participation. Limitations Limitations of this study include non-generalizable data beyond the two collegiate conferences. Second, this study was limited to contact and collision sports in one academic year, whereas future research may benefit from including additional sports and years. Also, using our current methods, we could not adjust for pre-existing or comorbid conditions or socio-demographic factors for all athletes that may be associated with increased SRC risk. These factors could potentially limit the generalizability of findings. Finally, we note that evidence of peak times for SRC, if contemplated in isolation, will not lead to SRC prevention. Instead, we encourage research activities to share these empirical findings with stakeholder groups (e.g., sports medicine clinicians, athletic administrators, coaches and athletes) given their knowledge of teams’ schedules, sports’ regulations, and availability of protective countermeasures that are already in place. Also, this collaborative model to identify priority timepoints, add contextual information and circumstances to complement documented injury frequencies, and prompt suggestions for preventative and accomplishable changes. Conclusion This study, using time-to-event analyses, provided insights into the distribution of SRC risk over time across and within contact and collision sports in two Division I athletic conferences. In a total of 369 SRC cases among 4,555 athletes across one academic year, we found the proportion of athletes free from SRC ranged from 80.4% in women’s rugby and 84.1% in sprint football to 95.6% in men’s soccer. With this approach we describe how common SRC were by sport, visualized relative temporality of concussion incidence across an academic year, and revealed sport-specific nuances that can serve as a model that to be applied in future research across more years, additional sports, and comprehensive injury surveillance across all injury categories. The present study benefits from having a stakeholder-engaged approach that we plan to thus utilize in next phases of this work. Abbreviations SRC Sport-related concussion HR hazard ratios CI confidence intervals CISG Concussion in Sport Group NCAA National Collegiate Athletic Association ISP Injury Surveillance Program AEs Athletic exposures DoD Department of Defense CARE Concussion Assessment, Research and Education Consortium HITS Head Impact Telemetry System MSK musculoskeletal Declarations Competing interests: The authors declare that they have no competing interests. Funding: DJW and ACB declare support from the Ivy League and Big Ten Presidents for efforts on this study. In addition, DJW, ACB, SS, and CK were supported by a grant to the University of Michigan Injury Prevention Center by the Centers for Disease Control & Prevention Award Number R49-CE-003552. The content is solely the responsibility of the authors and does not necessarily represent the official views of the Centers for Disease Control & Prevention or the Department of Health and Human Services. DJW has received funds for expert testimony on long-term consequences of sports concussions and traumatic brain injuries. Author Contribution Authors' contributions: DJW, ACB, SS made substantial contributions to the conception and design of this work. DJW, ACB, SS, CK, provided interpretation of the data, drafted the work or substantially revised it, provided approval for the submitted version, and agreed both to be personally accountable for the author's own contributions and ensured that this work was reported with accuracy or integrity. DJW served as the overall study PI. Additionally, as part of her role on the study management team of the Ivy B1G study, ACB role on this project included providing mentorship to engage SS as an epidemiology master’s student collaborator. Acknowledgement We acknowledge study personnel across participating Ivy League and Big Ten campuses, and we acknowledge the student- athletes participating in the Ivy League-Big Ten Epidemiology of Concussion Study. The authors give thanks to members of the Study Advisory Committee: Art Maerlender, PhD, ABPP- CN; Cary R. Savage, PhD; Emily A. Dorman, MEd, ATC; James C. Torner, PhD, MS; Jeffrey M. Mjaanes, MD; James M. Noble, MD, MS; Carrie Esopenko, PhD and additional study leadership: Carolyn Campbell- McGovern, MBA and Robin Harris (the Ivy League). The authors also thank Andrew Belfiglio, MPH, Christopher Knaub, MSGH, and Nichole Burnside, MBA for study management and coordination. The authors also thank Dr. Jason Goldstick for advice about statistical modelling. Data Availability Data are not publicly available due to restrictions under data sharing agreements between participating sites. References Association NCA. NCAA Sports Sponsorship and Participation Rates Database [data visualization dashboard]. 2024 October, 2024. Boltz AJ, Nedimyer AK, Chandran A, Robison HJ, Collins CL, Morris SN. Epidemiology of Injuries in National Collegiate Athletic Association Men's Ice Hockey: 2014–2015 Through 2018–2019. J Athl Train. 2021;56(7):703–10. Bretzin AC, D'Alonzo BA, Chandran A, Boltz AJ, Robison HJ, Collins CL, et al. 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19:31:30","extension":"html","order_by":13,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":145484,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7633996/v1/60b1b12d1d2e406b222b62e4.html"},{"id":92895938,"identity":"8e2cfd50-7803-43c0-af26-64450501a205","added_by":"auto","created_at":"2025-10-06 19:23:29","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":326039,"visible":true,"origin":"","legend":"\u003cp\u003eEvent history plot displaying incident sport-related concussion(s) (SRC) across an academic year in collegiate athletes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLegend. \u003c/strong\u003eExample of individual athlete follow-up time displaying the following scenarios: a) following an athlete from the start of the season through the end, with no diagnosed sport-related concussion (SRC); b) following an athlete from the start of the season to SRC without returning to play; c) following an athlete from the start of the season to first SRC and from return to play to end of academic year; d) following athlete from the start of the season to first SRC, return to play to second SRC, and return to play to the end of the academic year.\u003c/p\u003e","description":"","filename":"Figure1..jpg","url":"https://assets-eu.researchsquare.com/files/rs-7633996/v1/dbfbabbaf45ec789aab9f5c9.jpg"},{"id":92895944,"identity":"01d19e50-3b45-4302-a600-5c5953777f3d","added_by":"auto","created_at":"2025-10-06 19:23:29","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":939591,"visible":true,"origin":"","legend":"\u003cp\u003eKaplan-Meier Curves and Sport-Related Concussions Percentages During Week of Academic Year: Fall Sports\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLegend. \u003c/strong\u003eFor each fall sport, we present the number of diagnosed sport-related concussion (SRC), survival time to SRC in days, and percent of all SRC a during each week throughout the academic year.\u003c/p\u003e","description":"","filename":"Figure2..jpg","url":"https://assets-eu.researchsquare.com/files/rs-7633996/v1/edba85a4b399d01b01e68d2a.jpg"},{"id":92896209,"identity":"68efd28a-77a6-4d94-8b07-b856c0032fc6","added_by":"auto","created_at":"2025-10-06 19:31:29","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":906615,"visible":true,"origin":"","legend":"\u003cp\u003eKaplan-Meier Curves and Sport-Related Concussions Percentages During Week of Academic Year: Winter and Spring Sports\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLegend. \u003c/strong\u003eFor each winter and spring sport, we present the number of diagnosed sport-related concussion (SRC), survival time to SRC in days, and percent of all SRC a during each week throughout the academic year.\u003c/p\u003e","description":"","filename":"Figure3..jpg","url":"https://assets-eu.researchsquare.com/files/rs-7633996/v1/1c7f0a3d4c088c9abe4924c7.jpg"},{"id":93535946,"identity":"7af65c38-3652-4843-9319-34adec081832","added_by":"auto","created_at":"2025-10-15 01:16:47","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3088731,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7633996/v1/836cba40-50d0-40db-9765-eda4ec275a05.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Use of Time-to-Event Analyses to Identify Concussion Prevention Opportunities During Athletic Seasons: Findings from The Ivy League-B1G Ten Epidemiology of Concussion Study","fulltext":[{"header":"Background","content":"\u003cp\u003eCollegiate sport participation continues to grow, with over 500,000 athletes at-risk for injury annually.(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e) The National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) reported that overall injury rates range from 4.9 per 1,000 athletic exposures (AEs) in Men\u0026rsquo;s Lacrosse to 9.3 per 1,000 AEs in football, with variability across men\u0026rsquo;s and women\u0026rsquo;s sports.(\u003cspan additionalcitationids=\"CR3 CR4 CR5 CR6 CR7 CR8 CR9\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e) Early research in collegiate athletic settings described that approximately 9.8% of game and 12.8% of practice injuries occur to the head and neck.(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e) Sport-related concussions (SRC) are a complicated and common head and neck injury, accounting for 5.2%, in men\u0026rsquo;s soccer, to 11.9%, in women\u0026rsquo;s ice hockey, of all injuries, depending on the sport.(\u003cspan additionalcitationids=\"CR3 CR4 CR5 CR6 CR7 CR8 CR9\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e) Further, preliminary estimates from the NCAA-ISP suggest an overall SRC rate of 4.5 per 10,000 athlete exposures between the 2009/10 through 2013/14 academic years.(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e) More recently, Chandran et al.(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) identified an overall SRC rate of 4.1 per 10,000 AE across all sports from 2014/15 through 2018/19. Importantly, this research identifies SRCs as prevalent injuries among contact and collision sports; yet, these methodologies don\u0026rsquo;t account for the temporality of SRC across an athletic season, which could inform the development of targeted prevention interventions.\u003c/p\u003e\u003cp\u003eUsing a prospective cohort design in the Ivy League-Big Ten Epidemiology of Concussion Study, Putukian et al.(\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e) reported that the majority (94.0%) of SRCs in collegiate athletics occurred during the regular season and 6% of SRCs occurred during the preseason across all sports. Separately, using data from the NCAA-Department of Defense (DoD) Concussion Assessment, Research and Education (CARE) Consortium, Broglio et al.(\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e) reported SRC rates in Division I football were similar between the preseason and spring seasons, and both were higher than fall SRC rates. In contrast, when using the Head Impact Telemetry System (HITS), a program used to record head impact exposure during helmeted football play, Stemper et al.(\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e) reported that the average concussion incidence, the total number of concussions over the number of consented and enrolled athletes, in Division I football was higher during the regular (3.5%) football season than the preseason (3.1%) and was the highest in 2015 (8.5%) during the five-year study period from 2015 through 2019. Separately, in high school football, Bretzin et al.(\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e) reported the frequency of SRCs occurring each week throughout the season, highlighting that the highest percentage of practice-related concussions occurred in the first two weeks before the first competition, and the highest percentage of competition-related concussions occurred in the middle of the athletic season (i.e., weeks 5\u0026ndash;9).\u003c/p\u003e\u003cp\u003eTo compliment these studies aimed at identifying timeframes of heightened SRC occurrence, advancing analytic approaches may prompt prevention efforts by understanding time-specific contextual factors that highlight key times during athletic seasons of which SRCs occur. As an example, in 2018, the NCAA reduced the number of preseason on-field practice events based on epidemiologic evidence that demonstrated SRCs were common during these activities and this period during the season.(\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e) Importantly, most research on SRC occurrence is limited to football, warranting research studying the temporality of SRC incidence in additional contact and collision sports.\u003c/p\u003e\u003cp\u003eFurther, research and awareness is growing regarding sex and gender-based differences in SRC incidence. For example, Covassin et al.(\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e) reported that women in comparable sports (i.e., soccer, lacrosse, ice hockey, etc.) had a 1.4 times greater incidence of reported SRC relative to their men counterparts in the same sports. More recently Chandran et al.(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) also reported that overall SRC rates were higher in women\u0026rsquo;s sports relative to men\u0026rsquo;s sports in soccer, basketball, and softball relative to baseball. Similarly, Bretzin et al.(\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e) found that girls\u0026rsquo; high school soccer teams demonstrated a 1.8 times greater risk of documented SRC and took a median of 2 days longer to return to play compared to boys\u0026rsquo; soccer. To extend the existing research, analytic approaches using time-to-event analyses may improve our understanding of the timing of when women sustain SRCs throughout an academic year and enable novel comparisons with men in the same sports.\u003c/p\u003e\u003cp\u003eIn addition to informing SRC prevention opportunities, improving methods to study the temporality of concussion can be applied in additional research contexts; for example, investigating repeated musculoskeletal (MSK) injuries across an athletic season, especially after SRC. In recent work by Oldham et al.(\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e), the authors reported approximately 28% of collegiate athletes sustained acute MSK injury within six months following a diagnosed concussion, with higher risk reported among collision sport athletes. Similarly, Brooks et al.(\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e) found that collegiate athletes across seven sports had 2.5 times the odds of sustaining a lower extremity MSK injury within 90 days after sustaining an SRC than athletes without a recent SRC. Incorporating time-to-event analyses in future studies may yield a better understanding of when athletes are at risk for subsequent injuries while appropriately accounting for time at risk.\u003c/p\u003e\u003cp\u003eWith this as our motivation, we aim to advance concussion prevention opportunities by incorporating time-to-event analyses in a large ongoing prospective cohort study of SRC in collegiate athletics. The overall purpose of this analysis was to describe the timing of SRC in contact and collision sports across a full academic year. We also compared the timing of SRC between men and women on comparable teams, hypothesizing the rate of SRC would be higher in women relative to men based on prior literature.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy Design\u003c/h2\u003e\u003cp\u003eWe conducted a prospective cohort study using the Ivy League-Big Ten Epidemiology of Concussion Study.(\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e) The [BLINDED FOR REVIEW] University Institutional Review Board (IRB) served as the central IRB, with reliance agreements and/or site-IRB agreements depending on the participating university. All athletes provided informed consent prior to participation in the study.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eData sources\u003c/h3\u003e\n\u003cp\u003eWe extracted data from contact and collision sports from the 2023\u0026ndash;2024 academic season, examining SRC within two Division I collegiate athletic conferences. Methodology from the Ivy League-Big Ten Epidemiology of Concussion Study was described previously.(\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/p\u003e\n\u003ch3\u003eStudy Population\u003c/h3\u003e\n\u003cp\u003eThe study population included 4,555 college-age athletes participating in contact and collision sports.\u003c/p\u003e\n\u003ch3\u003eOperational Definitions\u003c/h3\u003e\n\u003cp\u003e\u003cem\u003eSport-Related Concussion\u003c/em\u003e. This study used the definition of SRC from the Concussion in Sport Group 2022 Amsterdam International Consensus Conference on Concussion in Sport. (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e) A concussion is defined as a traumatic brain injury caused by a blow to the head, neck, or body resulting in an impulsive force being transmitted to the brain that occurs in sports and exercise-related activities. This injury presents signs and symptoms that cannot be explained by any other cause. Concussions are recognized and/or reported to sports medicine teams across each athletics program. Team physicians in each program conduct a multifaceted assessment aligning with current consensus and practice guidelines to make concussion diagnoses. Diagnosed concussions, characteristics of the injured athletes, and recovery information are reported by trained research assistants at participating campuses. For the purposes of this study, only SRC were included in analyses.\u003c/p\u003e\u003cp\u003e\u003cem\u003eAcademic Year\u003c/em\u003e. The term academic year was defined as the period starting on August 1st, 2023, through the follow-up period of June 30th, 2024.\u003c/p\u003e\u003cp\u003e\u003cem\u003eContact and Collision Sports\u003c/em\u003e. This analysis comprised contact and collision sports which included men\u0026rsquo;s and women\u0026rsquo;s lacrosse, soccer, wrestling, rugby, and ice hockey, men\u0026rsquo;s football and sprint football, and women\u0026rsquo;s field hockey and varsity rugby. Men\u0026rsquo;s rugby was not included in this study, as men\u0026rsquo;s teams at participating campuses participate at the club, not varsity level.\u003c/p\u003e\u003cp\u003e\u003cem\u003eConcussion monitoring.\u003c/em\u003e Figure\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e1\u003c/span\u003e presents examples of the identification of SRC onset as well as repeat SRC among the same athletes during the academic year were identified over the follow-up period. The figure specifically displays the following scenarios: following an athlete from the start of the season through the end, with no diagnosed SRC; following an athlete from the start of the season to first SRC and from return to play to end of academic year; following athlete from the start of the season to first SRC, return to play to second SRC, and return to play to the end of the academic year; and following an athlete from the start of the season to SRC without returning to play.\u003c/p\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eWe reported descriptive statistics using medians and interquartile ranges for continuous variables, and frequencies with percentages for categorical variables. We used time-to-event analyses allowing for repeat events (i.e., athletes that sustained multiple SRCs during the same academic year) to describe the temporality of SRC risk across the academic year. With an Andersen-Gill model for analyzing time-to-repeated events, we completed independent Kaplan-Meier Survival to display the proportion of athletes without a diagnosed SRC throughout the academic year within each sport.\u003c/p\u003e\u003cp\u003eWe estimated survival functions to report the proportion of athletes without a diagnosed SRC by 30 days, 60 days, 90 days, and the end of the academic year. In addition to Kaplan-Meier Survival plots, we present the percentage of all diagnosed SRC that occurred each week during the academic year. Kaplan-Meier curves and percentage plots are presented in the same graph with defined axes.\u003c/p\u003e\u003cp\u003eWe also compared the instantaneous rate between men\u0026rsquo;s and women\u0026rsquo;s teams in the sport (HR) using Cox proportional hazard models. We used Schoenfeld residual plots to evaluate the proportional hazards assumption. We determined significance if the 95% confidence interval (CI) excluded one. All analyses were completed in STATA (18.2, StataCorp LLC, College Station, Texas).\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eOut of the 4,555 athletes (male: n\u0026thinsp;=\u0026thinsp;3,168, 69.6%, female: n\u0026thinsp;=\u0026thinsp;1387, 30.5%) that were included in contact and collision sports during the 2023/24 academic year, 369 concussions occurred (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). There were 356 (7.82%) athletes that sustained one SRC and 13 (0.3%) athletes that sustained more than one SRC during the academic year.\u003c/p\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e presents the percentage of SRC by each men\u0026rsquo;s and women\u0026rsquo;s sport. Overall, 281 (76.2%) men and 88 (23.9%) women sustained an SRC. Almost half (n\u0026thinsp;=\u0026thinsp;178, 48.2%) of the SRC cases did not have a history of previous concussion(s). Across all sports, practice (n\u0026thinsp;=\u0026thinsp;192, 52.2%) and competition (n\u0026thinsp;=\u0026thinsp;150, 41.0%) accounted for the highest percentages of SRC, respectively. Freshman (n\u0026thinsp;=\u0026thinsp;91, 24.8%) and Sophomore (n\u0026thinsp;=\u0026thinsp;91, 24.8%) athletes accounted for almost half of all SRCs.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eCharacteristics of Student-Athletes during 2023/24 Academic Year\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDemographics\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003en\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e%\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGender\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3168\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e69.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1387\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e30.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSport\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFootball\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1692\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e37.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Lacrosse\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e471\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Soccer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e432\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e9.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Wrestling\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e399\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e8.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Lacrosse\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e370\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e8.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Soccer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e295\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eField Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e284\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Ice Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e219\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Ice Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e182\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Rugby\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSprint Football\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e92\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Wrestling\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e\u003cp\u003ePercent of Student-Athletes Sustaining Concussion(s) during academic year\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4,186\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e91.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e356\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eCharacteristics of Sport-Related Concussion Cases* during the 2023/24 Academic Year\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eDiagnosed Sport-Related Concussion Cases\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003en\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e%\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGender\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e281\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e76.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e88\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSport\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFootball\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e155\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e42.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Soccer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Wrestling\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Lacrosse\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Ice Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Lacrosse\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Ice Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSprint Football\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Rugby\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eField Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Soccer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Wrestling\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePrevious Concussion History\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e178\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e48.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e101\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e27.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e12.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3+\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMissing\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eActivity Type\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePractice\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e192\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e52.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCompetition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e150\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e41.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eScrimmage\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eStrength and Conditioning\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSport-specific unsupervised activity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOther\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eClass year\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFreshman\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e24.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSophomore\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e24.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eJunior\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e89\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e24.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSenior\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e72\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e19.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFifth Year\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSixth Year\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSeventh Year\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e\u003cp\u003e*Athletes with multiple SRC in one academic year were reported twice\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003eSRC Timing During Academic Year Overall\u003c/h3\u003e\n\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e presents the percentage of athletes without a diagnosed SRC in 30-day time intervals across the academic year. Across all sports, by 30 days 98.9%, 60 days 97.6%, 90 days 95.9%, and by end of the academic year 92.3% of athletes were free from SRC, respectively. In men, by 30 days 98.6%, 60 days 97.39%, 90 days 95.8%, and by the end of academic year 92.0% of athletes were free from SRC, respectively. In women, by 30 days 99.4%, 60 days 98.3%, 90 days 96.1%, and by the end of academic year 92.6% of athletes were free from SRC, respectively. Across all sports, there was no association in the instantaneous rate of SRC between men and women (HR:1.09, 95% CI: 0.87, 1.37).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSurvival Estimates Describing the Percent of Student-Athletes Free from Diagnosed Concussion at Several Timepoints during Academic Year and Comparisons between sports with Men's and Women's Teams\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"12\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eSport\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"8\" nameend=\"c10\" namest=\"c3\"\u003e\u003cp\u003ePercent (%) of Student-Athletes Free from Sport-Related Concussion\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c12\" namest=\"c11\"\u003e\u003cp\u003eComparable Sports\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e30 days\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e95% CI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e60 days\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e95% CI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e90 days\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e95% CI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eAcademic Year End\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e95% CI\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eHazard Ratio\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e95% CI\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eCombined\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e98.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(98.5, 99.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e97.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(97.1, 98.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e95.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(95.3, 96.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e92.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(91.5, 93.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e98.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(98.2, 99.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e97.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(96.7, 97.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e95.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(95.0, 96.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e92.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(91.0, 93.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e1.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e(0.9, 1.4)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e99.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(98.8, 99.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e98.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(97.4, 98.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e96.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(94.9, 97.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e92.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(91.0, 93.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eFall Sports\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Rugby\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e98.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(92.5, 99.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e96.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(90.3, 98.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e88.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(79.9, 93.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e80.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(71.0, 87.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSprint Football\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e96.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(90.2, 98.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e88.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(79.6, 93.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e86.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(77.3, 91.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e84.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(75.1, 90.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFootball\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e97.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(96.9, 98.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e95.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(94.8, 96.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e94.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(93.0, 95.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e91.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(89.8, 92.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Soccer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e98.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(96.4, 99.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e95.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(92.6, 97.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e(0.3, 1.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Soccer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e99.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(97.5, 99.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e97.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(96.0, 98.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e95.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(93.3, 97.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e92.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(89.2, 94.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eField Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e98.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(96.3, 99.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e98.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(96.3, 99.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e96.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(94.1, 98.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e94.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(91.5, 96.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eWinter Sports\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Ice Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e99.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e(96.8, 99.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e98.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(95.8, 99.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e96.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(92.9, 98.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e89.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(84.7, 92.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e1.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e(0.7, 2.6)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Ice Hockey\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e98.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(95.0, 99.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e95.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(91.5, 97.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e92.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(87.1, 95.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Wrestling\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e99.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(97.4, 99.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e93.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(90.2, 95.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Wrestling\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eSpring Sports\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen's Lacrosse\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e99.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(98.5, 99.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e98.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(97.2, 99.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e94.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(92.4, 96.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e1.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e(0.6, 1.8)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWomen's Lacrosse\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e100.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e--\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e98.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(96.8, 99.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e97.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e(95.7, 98.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e94.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e(91.9, 96.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\n\u003ch3\u003eSRC Timing During Academic Year for Individual Sports\u003c/h3\u003e\n\u003cp\u003eIndependent Kaplan-Meier curves present the proportion of athletes without a diagnosed SRC throughout the academic year within each sport. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e2\u003c/span\u003e presents fall sports, and Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e3\u003c/span\u003e presents winter and spring sports.\u003c/p\u003e\u003cp\u003e\u003cem\u003eFootball.\u003c/em\u003e The Kaplan-Meier curve revealed diagnosed SRC in football (n\u0026thinsp;=\u0026thinsp;155) occurred early in the academic year prior to the first game of the season. The proportion of athletes sustaining a SRC consistently increased during the season, then paused throughout winter months. Diagnosed SRCs occurred again in weeks prior to and during the spring season scrimmages.\u003c/p\u003e\u003cp\u003eIn football, weeks 2 (9.0%) and 15 (9.0%) accounted for the highest percentages of diagnosed SRC. Weeks 1, 3, and 10 accounted for 7.1% of SRCs, respectively. Spring football in weeks 36 and 37 accounted for 5.2% and 3.2% of diagnosed SRCs, respectively.\u003c/p\u003e\u003cp\u003eOverall, in football, by 30 days 97.7%, 60 days 95.9%, 90 days 94.2%, and end of the academic year 91.2% of athletes were free from SRC.\u003c/p\u003e\u003cp\u003e\u003cem\u003eSprint Football.\u003c/em\u003e The Kaplan-Meier curve revealed no SRC occurred during pre-season in sprint football. Whereas SRC occurred throughout the regular season with the highest percentage of the total (n\u0026thinsp;=\u0026thinsp;16) concussions occurring during week 6 (31.2%), and weeks 4, 7, 12, and 14 each accounting for 12.5% of SRCs, respectively. By 30 days 96.7%, 60 days 88.1%, 90 days 86.1%, and end of the academic year 84.1% of athletes were free from SRC.\u003c/p\u003e\u003cp\u003e\u003cem\u003eField Hockey\u003c/em\u003e. SRCs in field hockey (n\u0026thinsp;=\u0026thinsp;15) occurred early after the start (week 4, 20.0%) and midpoint (week 11, 13.3%) of the fall season, and at the start of the spring season (week 31, 20.0%). In field hockey, 30 days 98.6%, 60 days, 90 days 96.9%, and end of the academic year 94.8% of athletes were free from SRC.\u003c/p\u003e\u003cp\u003e\u003cem\u003eWomen\u0026rsquo;s Rugby\u003c/em\u003e. In women\u0026rsquo;s rugby, SRC (n\u0026thinsp;=\u0026thinsp;19) occurred during pre-season and throughout duration of the fall season, with week 12 observably at the highest percentage (26.3%) of SRCs. Then SRC again occurred prior to the start of the spring season in February through May. Week 35 during the spring season accounted for 10.5% of SRCs. By 30 days 98.9%, 60 days 96.8%, 90 days 88.4%, and end of the academic year 80.4% of athletes were free from SRC.\u003c/p\u003e\u003cp\u003e\u003cem\u003eSoccer.\u003c/em\u003e In men\u0026rsquo;s soccer, SRC (n\u0026thinsp;=\u0026thinsp;14) first occurred in October, mid-way through the fall season, prior to the start of the spring season, and throughout the spring season. Weeks 12 and 31 observably had the highest percentages (15.4%) of diagnosed SRCs, respectively. By 30 days 100%, 60 days 100%, 90 days 98.6%, and end of the academic year 95.6% of athletes were free from SRC.\u003c/p\u003e\u003cp\u003eIn women\u0026rsquo;s soccer, SRCs (n\u0026thinsp;=\u0026thinsp;37) occurred during pre-season, throughout the regular season, immediately following the regular season, and during the spring season. Weeks 9 and 12 (11.4%) accounted for the highest percentage of diagnosed SRC, respectively. By 30 days 99.1%, 60 days 97.9%, 90 days 95.6%, and by the end of the academic year 92.1% of athletes were free from SRC. There was no significant difference in the instantaneous rate of SRC between men\u0026rsquo;s and women\u0026rsquo;s soccer (HR: 0.5, 95% CI: 0.3, 1.0).\u003c/p\u003e\u003cp\u003e\u003cem\u003eIce Hockey.\u003c/em\u003e In men\u0026rsquo;s hockey, SRCs (n\u0026thinsp;=\u0026thinsp;24) occurred throughout the pre-season and duration of the regular season. Week 13 observably had the highest percentage (12.5%) of diagnosed SRC. While diagnosed SRCs steadily occurred throughout later weeks toward the end of the competitive season. At 30 days 99.5%, 60 days 98.6%, 90 days 96.4%, and by the end of the academic year 89.5% of athletes in men\u0026rsquo;s hockey were free from SRC.\u003c/p\u003e\u003cp\u003eIn women\u0026rsquo;s ice hockey, SRCs (n\u0026thinsp;=\u0026thinsp;16) occurred during pre-season with the majoring occurring during the early weeks of the regular season. Week 13 (31.2%) observably had the highest percentage of diagnosed SRC, followed by weeks 16 and 18 accounting for 12.5%, respectively. By 30 days 100%, 60 days 98.4%, 90 days 95.7%, and at the end of the academic year 92.0% of athletes were free from SRC. There was no significant difference in the instantaneous rate of SRC between men\u0026rsquo;s in women\u0026rsquo;s ice hockey (HR: 1.3, 95% CI: 0.7, 2.6).\u003c/p\u003e\u003cp\u003e\u003cem\u003eWrestling.\u003c/em\u003e In wrestling (n\u0026thinsp;=\u0026thinsp;28) SRC began to occur at the start of the regular season. The highest percents of SRCs were observed in the middle of the season during weeks 16 and 22 each 14.3%, respectively. By 30 days 100%, 60 days 100%, 90 days 99.0%, and at the end of the academic year 93.2% of athletes were free from SRC. For the 2023/24 season, women\u0026rsquo;s wrestling had one team of 26 athletes, where no SRCs were reported.\u003c/p\u003e\u003cp\u003e\u003cem\u003eLacrosse\u003c/em\u003e. In men\u0026rsquo;s lacrosse, no SRCs occurred prior to the start of the fall season. SRC (n\u0026thinsp;=\u0026thinsp;26) did occur throughout the fall season, yet the highest percentages of SRC were observed early in the spring season during weeks 27 and 29 each at 11.5%, respectively. By 30 days 100%, 60 days 99.8%, 90 days 98.7%, and end of the academic year 94.8% of athletes were free from SRC.\u003c/p\u003e\u003cp\u003eIn women\u0026rsquo;s lacrosse no SRCs occurred prior to the start of the fall season. The highest percentages of SRCs (n\u0026thinsp;=\u0026thinsp;26) were observed during weeks 6, 10, and 14 each accounting for 15.0%, respectively. The highest percentage of SRCs during the spring season was 10.0% during week 36. By 30 days 100%, 60 days 98.7%, 90 days 97.9%, and end of the academic year 94.7% of athletes in women\u0026rsquo;s lacrosse were free from SRC. The instantaneous rate of SRC did not differ between men\u0026rsquo;s and women\u0026rsquo;s lacrosse (HR: 1.0, 95% CI: 0.6, 1.8).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis is the first study, to date, approaching the study of SRC incidence with time-to-event analyses, providing insights into the timing of SRC occurrence in contact and collision sports across a full academic year. A total of 369 SRCs occurred among 4,555 athletes, and by the end of the academic year, the proportion of athletes free from SRC ranged from 80.4% in women\u0026rsquo;s rugby and 84.1% in sprint football to 95.6% in men\u0026rsquo;s soccer. These results are consistent with previous research regarding general timing; however, this study extends prior research that provides the crude frequency of how often events happen relative to opportunities for them to happen (i.e., SRC per AEs). In this study, our time-to-event analyses brings novel attention to the distribution of SRC risk over time across and within sports. These methods should serve as a model that can be applied in future research across more years, additional sports, and comprehensive injury surveillance across all injury categories.\u003c/p\u003e\u003cp\u003ePrevious research reporting on the incidence or prevalence of SRCs through AE over the course of an athletic season, or academic year documents a crude frequency of injury occurrence relative to at-risk time,(\u003cspan additionalcitationids=\"CR3 CR4 CR5 CR6 CR7 CR8 CR9 CR10 CR11 CR12 CR13\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e) and to date, often describes the general timing of SRCs based on the segmental parts of the season (e.g., pre-season, regular season, post-season).(\u003cspan additionalcitationids=\"CR16\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e) Furthermore, many of these details are limited to football,(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan additionalcitationids=\"CR16 CR17\" citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e) despite growing evidence of high or equivalent SRC incidence among additional collegiate contact and collision sports. In the present study, we reported on overall rates plus the timing of SRCs over the course of an academic year, in multiple contact and collision sports.\u003c/p\u003e\u003cp\u003eWe identified a range of 4.4% to 19.6% of athletes sustained a SRC during the academic year, depending on the sport. Prior research shows that women consistently exhibit higher SRC rates than men in comparable sports.(\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e) In the current study, when accounting for the proportion and timing of SRC, we found no difference in the instantaneous rate of SRC between men\u0026rsquo;s and women\u0026rsquo;s lacrosse. Prior research using frequency of injury relative to exposure time reported that men\u0026rsquo;s lacrosse exhibited higher SRC rates than women\u0026rsquo;s lacrosse;(\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e) in contrast more recently, Chandran et al.(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) did not include lacrosse when comparing injury rates in men\u0026rsquo;s and women\u0026rsquo;s lacrosse. Further, Bretzin et al. reported SRC clinical incidence among high school sports reporting earlier years boys\u0026rsquo; lacrosse had higher rates and in more recent years during the study period girls\u0026rsquo; lacrosse demonstrated higher rates. Together, these results paired with 5.2% of men\u0026rsquo;s and 5.3% of women\u0026rsquo;s lacrosse athletes sustaining a concussion by the end of the academic year in the present study suggest SRC injuries are prevalent in lacrosse, warranting continued research combining collaborated efforts between investigators, coaches, and policy makers to enhance safe sport participation among collegiate lacrosse athletes.\u003c/p\u003e\u003cp\u003eDespite non-significant findings, in the present study men\u0026rsquo;s ice hockey had a 30% higher hazard of SRC than women\u0026rsquo;s ice hockey, and men\u0026rsquo;s soccer players had a 46% lower hazard of diagnosed SRC than women\u0026rsquo;s soccer players. These results from a one-year study period suggest that there may be differences in the instantaneous rate of SRCs in various sports between men\u0026rsquo;s and women\u0026rsquo;s teams. Prior work in ice hockey is inconsistent, with early findings demonstrating higher rates in men\u0026rsquo;s relative to women\u0026rsquo;s ice hockey,(\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e) and no differences between men and women in more recent years.(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e) In soccer, akin to prior research,(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e) our study found a trend for significance as athletes in women\u0026rsquo;s soccer sustained more SRCs than in men\u0026rsquo;s. In addition, this study extends the findings of prior work as we demonstrated that SRC injuries for women started early in the fall season with an observably steeper slope than men, resulting in 7.9% of women and 4.4% of men with a diagnosed SRC by the end of the academic year inclusive of both fall and spring seasons in soccer. Additional years of data in future analyses might yield significant results more closely aligning with prior research. Similarly, more research is warranted to study SRC incidence in women\u0026rsquo;s wrestling as it grows in popularity. In the current analyses, we were limited to one team with 26 women participating at the NCAA varsity level, and no concussions were reported.\u003c/p\u003e\u003cp\u003eUnsurprisingly, football athletes experienced most of their SRCs within the first 60 days, accounting for 45.8% of all football SRCs. Our study demonstrated that 24.6% of SRC occurred during the first four weeks, and 62.7% occurred between week 5 and the last regular season game; while prior research shows that most SRC in football occur in the preseason.(\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e) We also found that approximately half of the SRCs occurred during practice (52.19%). There is contention in previous literature about where SRCs occur most frequently, practice or competition, as Zuckerman et al.(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e) reported a higher proportion of SRCs occurred during competition, while McCrea et al.(\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e) found that more SRCs were obtained during practice in football. Notably, at risk time is often higher in practice verses competition, as a greater number of athletes participate in more hours of practice relative to competition motivating prevention initiatives that limit head repetitive neurotrauma during practice situations.(\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e) Nonetheless, utilizing time-to-event analysis we can identify the specific periods that athletes are at heightened risk for SRC during the athletic season, share these findings with key stakeholders (e.g., coaches, sports medicine clinicians, athletic directors, policy makers), and collaboratively initiate and test the effectiveness of prevention activities, as successfully demonstrated within our study infrastructure.(\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e)\u003c/p\u003e\u003cp\u003eIn addition to an application of time-to-event analyses, this study provides a novel contribution as one of the first to document the epidemiology of SRC within sprint football, which exhibited one of the highest percentages of athletes with a SRC by the end of the season. In sprint football, approximately 15.9% of athletes sustained an SRC by the end of their season. Most concussions occurred within the first 60 days of the start of the season, accounting for 68.8% of all sprint football concussions. Despite its foundation as a sport in the early 1930\u0026rsquo;s, research investigating SRC, and overall injury, in sprint football is limited. Sprint football is currently underway at two of the campuses participating in the present study, with a total of 92 sprint football athletes at risk for concussion in our study period. Existing research for the epidemiology of injury within the sport include a study by D\u0026rsquo;Alonzo et al.(\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e) who combined sprint football with additional high-contact sports to compare recovery outcomes between men and women at different sport participation contact levels. However, such methodologies do not enable understanding of SRC recovery characteristics among sprint football athletes uniquely. Similarly, Wiebe and colleagues(\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e) studied the stepwise return to sport progression among contact athletes with SRC, of which 3% of the sample included sprint football athletes; however, the authors did not report sport-specific findings. Separately, in a report of SRC recovery among collegiate athletes, Bretzin and colleagues(\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e) identified sprint football accounted for 4.1% of SRC among men, and documented between 30\u0026ndash;40% of sprint football athletes had a previous history of concussion.\u003c/p\u003e\u003cp\u003eSport-specific nuances within sprint football parallel those observed in wrestling, with a strict 178-pound weight limit for sprint football and weigh-ins occurring 2\u0026ndash;4 days before a game. Thus, sprint football athletes may also use rapid weight cutting measures, which are currently understood to be associated with concussion symptoms and dehydration.(\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e) However, more research is needed in this area. Separately, mechanisms of injury and SRC injury risk may be different than traditional American football, with smaller athletes and faster, more dynamic play, sprint football defenses rely on speed and execution rather than traditional football strategies. Taken together, these findings should motivate further stakeholder-engaged research and drive the initiation and evaluation of prevention initiatives in underrepresented sports.\u003c/p\u003e\u003cp\u003eWomen\u0026rsquo;s rugby demonstrated the highest percentage (19.6%) of athletes sustaining SRC by the end of the academic year, overall. Women\u0026rsquo;s rugby is comprised of two seasons: 7\u0026rsquo;s during the fall and 15\u0026rsquo;s during the spring. Over half (52.7%) of SRC occurred during fall 7\u0026rsquo;s, with the highest percentage at the end of the fall season (26.2%). Each season represents a different number of athletes on the field during game play, while using the same field dimensions (i.e., 100x70 meters). Also, the two seasons hold different game durations, as 7s have two 7-minute halves requiring repeated high-intensity sprints often with multiple matches played in one day, and 15s has two 40-minute halves requiring endurance, pacing, and sustained physical contests. Thus, women\u0026rsquo;s rugby 7s and 15s differ in player numbers, game duration, and style of play, resulting in distinct physical demands, technical requirements, and potentially injury risks. With increasing attention to the epidemiology of SRC in women\u0026rsquo;s rugby,(\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan additionalcitationids=\"CR31 CR32 CR33 CR34 CR35 CR36\" citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e) our findings and study infrastructure highlight the importance of stakeholder-engaged research and support the initiation and evaluation of prevention initiatives in collegiate women\u0026rsquo;s rugby. By studying both 7s and 15s, our study provides a framework for applying these analytic methods in future injury research.\u003c/p\u003e\u003cp\u003eLike rugby, football, lacrosse, field hockey, and soccer each have multiple seasons with competitive events at the collegiate level. Our findings demonstrate that SRCs occur across both periods, with a resurgence of injury within each sport. This suggests that SRC risk at the collegiate level is not solely restricted to the formal competitive season and can emerge during off-season, or second season activities. Competitive football play mainly occurs during the fall season, which we observed had the most SRC. The spring season yielded a lower percentage of SRCs; however, we observed an increase in SRC particularly around the spring season scrimmage. Recent discourse in collegiate athletics has highlighted a movement toward eliminating the spring scrimmage game, which could influence injury incidence. Additionally, with the recent addition of the NCAA transfer portal, programs may change the shape and design of spring practices and conditioning for the next competitive season, potentially impacting SRC risk. Separately, we observed higher rates for lacrosse during the spring competitive season but also found that SRCs occur during the shorter fall season. In field hockey, we observed most SRC within the fall season, which is the primary competitive with a longer schedule while the spring season is focused on skill development. There is a similar structure in soccer, and our data displayed the majority of SRC were sustained during the fall, while we observed an earlier frequency of injury in the spring season in men relative to women. Together, this study provided a novel opportunity to apply an analytic method that captures the distribution of injury risk across the year in contact and collision sports. This approach revealed sport-specific nuances and highlights the potential for continued research. With additional years of data and the inclusion of more sports, we aim to share these findings with stakeholder groups to inform, plan, implement, and evaluate targeted prevention strategies that promote safe sport participation.\u003c/p\u003e\u003cp\u003eLimitations\u003c/p\u003e\u003cp\u003eLimitations of this study include non-generalizable data beyond the two collegiate conferences. Second, this study was limited to contact and collision sports in one academic year, whereas future research may benefit from including additional sports and years. Also, using our current methods, we could not adjust for pre-existing or comorbid conditions or socio-demographic factors for all athletes that may be associated with increased SRC risk. These factors could potentially limit the generalizability of findings. Finally, we note that evidence of peak times for SRC, if contemplated in isolation, will not lead to SRC prevention. Instead, we encourage research activities to share these empirical findings with stakeholder groups (e.g., sports medicine clinicians, athletic administrators, coaches and athletes) given their knowledge of teams\u0026rsquo; schedules, sports\u0026rsquo; regulations, and availability of protective countermeasures that are already in place. Also, this collaborative model to identify priority timepoints, add contextual information and circumstances to complement documented injury frequencies, and prompt suggestions for preventative and accomplishable changes.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study, using time-to-event analyses, provided insights into the distribution of SRC risk over time across and within contact and collision sports in two Division I athletic conferences. In a total of 369 SRC cases among 4,555 athletes across one academic year, we found the proportion of athletes free from SRC ranged from 80.4% in women\u0026rsquo;s rugby and 84.1% in sprint football to 95.6% in men\u0026rsquo;s soccer. With this approach we describe how common SRC were by sport, visualized relative temporality of concussion incidence across an academic year, and revealed sport-specific nuances that can serve as a model that to be applied in future research across more years, additional sports, and comprehensive injury surveillance across all injury categories. The present study benefits from having a stakeholder-engaged approach that we plan to thus utilize in next phases of this work.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eSRC\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eSport-related concussion\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eHR\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003ehazard ratios\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCI\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003econfidence intervals\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCISG\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eConcussion in Sport Group\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eNCAA\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eNational Collegiate Athletic Association\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eISP\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eInjury Surveillance Program\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eAEs\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eAthletic exposures\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eDoD\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eDepartment of Defense\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eCARE\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eConcussion Assessment, Research and Education Consortium\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eHITS\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003eHead Impact Telemetry System\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv class=\"DefinitionListEntry\"\u003e\u003cdiv class=\"Term\"\u003eMSK\u003c/div\u003e\u003cdiv class=\"Description\"\u003e\u003cp\u003emusculoskeletal\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003c/div\u003e"},{"header":"Declarations","content":"\u003ch2\u003eCompeting interests:\u003c/h2\u003e\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e\u003cp\u003eDJW and ACB declare support from the Ivy League and Big Ten Presidents for efforts on this study. In addition, DJW, ACB, SS, and CK were supported by a grant to the University of Michigan Injury Prevention Center by the Centers for Disease Control \u0026amp; Prevention Award Number R49-CE-003552. The content is solely the responsibility of the authors and does not necessarily represent the official views of the Centers for Disease Control \u0026amp; Prevention or the Department of Health and Human Services. DJW has received funds for expert testimony on long-term consequences of sports concussions and traumatic brain injuries.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAuthors' contributions: DJW, ACB, SS made substantial contributions to the conception and design of this work. DJW, ACB, SS, CK, provided interpretation of the data, drafted the work or substantially revised it, provided approval for the submitted version, and agreed both to be personally accountable for the author's own contributions and ensured that this work was reported with accuracy or integrity. DJW served as the overall study PI. Additionally, as part of her role on the study management team of the Ivy B1G study, ACB role on this project included providing mentorship to engage SS as an epidemiology master\u0026rsquo;s student collaborator.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eWe acknowledge study personnel across participating Ivy League and Big Ten campuses, and we acknowledge the student- athletes participating in the Ivy League-Big Ten Epidemiology of Concussion Study. The authors give thanks to members of the Study Advisory Committee: Art Maerlender, PhD, ABPP- CN; Cary R. Savage, PhD; Emily A. Dorman, MEd, ATC; James C. Torner, PhD, MS; Jeffrey M. Mjaanes, MD; James M. Noble, MD, MS; Carrie Esopenko, PhD and additional study leadership: Carolyn Campbell- McGovern, MBA and Robin Harris (the Ivy League). The authors also thank Andrew Belfiglio, MPH, Christopher Knaub, MSGH, and Nichole Burnside, MBA for study management and coordination. The authors also thank Dr. Jason Goldstick for advice about statistical modelling.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eData are not publicly available due to restrictions under data sharing agreements between participating sites.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAssociation NCA. NCAA Sports Sponsorship and Participation Rates Database [data visualization dashboard]. 2024 October, 2024.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBoltz AJ, Nedimyer AK, Chandran A, Robison HJ, Collins CL, Morris SN. Epidemiology of Injuries in National Collegiate Athletic Association Men's Ice Hockey: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):703\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBretzin AC, D'Alonzo BA, Chandran A, Boltz AJ, Robison HJ, Collins CL, et al. Epidemiology of Injuries in National Collegiate Athletic Association Women's Lacrosse: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):750\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChandran A, Morris SN, Boltz AJ, Robison HJ, Collins CL. Epidemiology of Injuries in National Collegiate Athletic Association Women's Soccer: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):651\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChandran A, Morris SN, Boltz AJ, Robison HJ, Collins CL. Epidemiology of Injuries in National Collegiate Athletic Association Men's Soccer: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):659\u0026ndash;65.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChandran A, Morris SN, Powell JR, Boltz AJ, Robison HJ, Collins CL. Epidemiology of Injuries in National Collegiate Athletic Association Men's Football: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):643\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChandran A, Nedimyer AK, Boltz AJ, Robison HJ, Collins CL, Morris SN. Epidemiology of Injuries in National Collegiate Athletic Association Women's Ice Hockey: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):695\u0026ndash;702.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eD'Alonzo BA, Bretzin AC, Chandran A, Boltz AJ, Robison HJ, Collins CL, et al. Epidemiology of Injuries in National Collegiate Athletic Association Men's Lacrosse: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):758\u0026ndash;65.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eNedimyer AK, Boltz AJ, Robison HJ, Collins CL, Morris SN, Chandran A. Epidemiology of Injuries in National Collegiate Athletic Association Women's Field Hockey: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):636\u0026ndash;42.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePowell JR, Boltz AJ, Robison HJ, Morris SN, Collins CL, Chandran A. Epidemiology of Injuries in National Collegiate Athletic Association Men's Wrestling: 2014\u0026ndash;2015 Through 2018\u0026ndash;2019. J Athl Train. 2021;56(7):727\u0026ndash;33.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHootman JM, Dick R, Agel J. Epidemiology of collegiate injuries for 15 sports: summary and recommendations for injury prevention initiatives. J Athl Train. 2007;42(2):311\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZuckerman SL, Kerr ZY, Yengo-Kahn A, Wasserman E, Covassin T, Solomon GS. Epidemiology of Sports-Related Concussion in NCAA Athletes From 2009\u0026ndash;2010 to 2013\u0026ndash;2014: Incidence, Recurrence, and Mechanisms. Am J Sports Med. 2015;43(11):2654\u0026ndash;62.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChandran A, Boltz AJ, Morris SN, Robison HJ, Nedimyer AK, Collins CL, et al. Epidemiology of Concussions in National Collegiate Athletic Association (NCAA) Sports: 2014/15-2018/19. Am J Sports Med. 2022;50(2):526\u0026ndash;36.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePutukian M, D'Alonzo BA, Campbell-McGovern CS, Wiebe DJ. The Ivy League-Big Ten Epidemiology of Concussion Study: A Report on Methods and First Findings. Am J Sports Med. 2019;47(5):1236\u0026ndash;47.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBroglio SP, Perkins SM, Riggen L, Stemper BD, Shah A, McAllister TW, et al. Similar Concussion Rates in Spring Football and Preseason: Findings From the Concussion Assessment, Research and Education Consortium. J Athl Train. 2023;58(3):220\u0026ndash;3.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eStemper BD, Harezlak J, Shah AS, Rowson S, Mihalik JP, Riggen L, et al. Association between Preseason/Regular Season Head Impact Exposure and Concussion Incidence in NCAA Football. Med Sci Sports Exerc. 2022;54(6):912\u0026ndash;22.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBretzin AC, Tomczyk CP, Wiebe DJ, Covassin T. Avenues for Sport-Related Concussion Prevention in High School Football: Effect of Limiting Collision Practices. J Athl Train. 2022;57(8):733\u0026ndash;40.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eStemper BD, Shah AS, Harezlak J, Rowson S, Duma S, Mihalik JP, et al. Repetitive Head Impact Exposure in College Football Following an NCAA Rule Change to Eliminate Two-A-Day Preseason Practices: A Study from the NCAA-DoD CARE Consortium. Ann Biomed Eng. 2019;47(10):2073\u0026ndash;85.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCovassin T, Moran R, Elbin RJ. Sex Differences in Reported Concussion Injury Rates and Time Loss From Participation: An Update of the National Collegiate Athletic Association Injury Surveillance Program From 2004\u0026ndash;2005 Through 2008\u0026ndash;2009. J Athl Train. 2016;51(3):189\u0026ndash;94.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBretzin AC, Covassin T, Wiebe DJ, Stewart W. Association of Sex With Adolescent Soccer Concussion Incidence and Characteristics. JAMA Netw Open. 2021;4(4):e218191.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eOldham JR, Bowman TG, Walton SR, Beidler E, Campbell TR, Smetana RM et al. Sport Type and Risk of Subsequent Injury in Collegiate Athletes Following Concussion: a LIMBIC MATARS Consortium Investigation. Brain Inj. 2024:1\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBrooks MA, Peterson K, Biese K, Sanfilippo J, Heiderscheit BC, Bell DR. Concussion Increases Odds of Sustaining a Lower Extremity Musculoskeletal Injury After Return to Play Among Collegiate Athletes. Am J Sports Med. 2016;44(3):742\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePatricios JS, Schneider KJ, Dvorak J, Ahmed OH, Blauwet C, Cantu RC et al. Consensus statement on concussion in sport: the 6th International Conference on Concussion in Sport-Amsterdam, October 2022. Br J Sports Med. 2023;57(11):695\u0026ndash;711.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMcCrea MA, Shah A, Duma S, Rowson S, Harezlak J, McAllister TW, et al. Opportunities for Prevention of Concussion and Repetitive Head Impact Exposure in College Football Players: A Concussion Assessment, Research, and Education (CARE) Consortium Study. JAMA Neurol. 2021;78(3):346\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWiebe DJ, D'Alonzo BA, Harris R, Putukian M, Campbell-McGovern C. Association Between the Experimental Kickoff Rule and Concussion Rates in Ivy League Football. JAMA. 2018;320(19):2035\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eD'Alonzo BA, Schneider ALC, Barnett IJ, Master CL, Bretzin AC, Wiebe DJ, et al. Associations of Sex and Sport Contact-Level with Recovery Timelines Among Collegiate Athletes with Sport-Related Concussion. Sports Med Open. 2024;10(1):86.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eWiebe DJ, Bretzin AC, D'Alonzo BA, the Ivy League-Big Ten Epidemiology of Concussion Study I. Progression through return-to-sport and return-to-academics guidelines for concussion management and recovery in collegiate student athletes: findings from the Ivy League-Big Ten Epidemiology of Concussion Study. Br J Sports Med. 2022;56(14):801\u0026ndash;11.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBretzin AC, Esopenko C, D'Alonzo BA, Wiebe DJ. Clinical Recovery Timelines After Sport-Related Concussion in Men's and Women's Collegiate Sports. J Athl Train. 2022;57(7):678\u0026ndash;87.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eUddin N, Waldron M, Patterson SD, Winter S, Tallent J. A Survey of Combat Athletes' Rapid Weight Loss Practices and Evaluation of the Relationship With Concussion Symptom Recall. Clin J Sport Med. 2022;32(6):580\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBaioccato V, Paronuzzi S, Bazo M, Zanardo E, Sattin V, Lorenzoni G, et al. Fourteen-year analysis of rugby injuries in a pediatric emergency department. Ital J Pediatr. 2025;51(1):220.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKing DA, Hume PA, Hind K, Clark TN, Hardaker N. The Incidence, Cost, and Burden of Concussion in Women's Rugby League and Rugby Union: A Systematic Review and Pooled Analysis. Sports Med. 2022;52(8):1751\u0026ndash;64.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePfister T, Pfister K, Hagel B, Ghali WA, Ronksley PE. The incidence of concussion in youth sports: a systematic review and meta-analysis. Br J Sports Med. 2016;50(5):292\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eScantlebury S, Jones B, Owen C, Brown J, Collins N, Fairbank L, et al. Time to level the playing field between men and women - Given similar injury incidence: A two-season analysis of match injuries in elite men and women's (Super League) rugby league. J Sci Med Sport. 2024;27(11):765\u0026ndash;71.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eStarling LT, Gabb N, Williams S, Kemp S, Stokes KA. Longitudinal study of six seasons of match injuries in elite female rugby union. Br J Sports Med. 2023;57(4):212\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eThomas J, Tomlinson O, Williams G, Bond B. Exploring concussion prevalence, knowledge and reporting behaviours in women playing rugby union in the United Kingdom. Phys Sportsmed. 2025;53(2):169\u0026ndash;77.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTucker R, Smith A, Hester B, Falvey E. Higher contact tackles from upright tacklers increases the risk of head injury removals in elite women's Rugby Union: A case-control study. J Sci Med Sport. 2025;28(9):700\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eYeomans C, Kenny IC, Cahalan R, Warrington GD, Harrison AJ, Purtill H, et al. Injury Trends in Irish Amateur Rugby: An Epidemiological Comparison of Men and Women. Sports Health. 2021;13(6):540\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7633996/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7633996/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground:\u003c/h2\u003e\u003cp\u003eWe aim to create concussion prevention opportunities using time-to-event analytic approaches. This study investigates the timing of sport-related concussion (SRC) incidence across a full academic year.\u003c/p\u003e\u003ch2\u003eMethod:\u003c/h2\u003e\u003cp\u003eIn a prospective cohort study, The Ivy League-Big Ten Epidemiology of Concussion Study, we examined SRCs within contact and collision sports across the two conferences during 2023\u0026ndash;2024 academic year. Survival analyses, using academic year start and end dates and dates of injury, investigated the timing of SRC onset in each sport. Kaplan-Meier curves and Cox proportional hazard models compared instantaneous risks using hazard ratios (HR) between men\u0026rsquo;s and women\u0026rsquo;s teams with 95% confidence intervals (CI).\u003c/p\u003e\u003ch2\u003eResults:\u003c/h2\u003e\u003cp\u003eOut of 4,555 contact and collision athletes in fall (n\u0026thinsp;=\u0026thinsp;2,888, 63.4%), winter (n\u0026thinsp;=\u0026thinsp;826, 18,1%), and spring (n\u0026thinsp;=\u0026thinsp;841, 18.5%) sports, 369 SRCs occurred; 13 athletes sustained repeat SRCs during the academic year. Football (n\u0026thinsp;=\u0026thinsp;155, 42.0%) and women\u0026rsquo;s soccer (n\u0026thinsp;=\u0026thinsp;37, 10.0%) accounted for the largest percentages of SRCs. Across all sports, by 30 days 98.9%, 60 days 97.6%, 90 days 95.9%, and by end of the academic year 92.3% were free from concussion, respectively. Within-sport, SRC proportions were highest during weeks 2 and 15 in football, the middle of the season (week 6) in sprint football, the end of the fall season (week 12) in women\u0026rsquo;s rugby, and early in the season (week 13) in women\u0026rsquo;s ice hockey. By the end of the academic year the proportion free from SRC was 81.7% (95%CI: 72.3\u0026ndash;88.2) to 95.6% (95%CI: 92.5\u0026ndash;97.4). There was no association in SRC hazard between men and women overall, (HR:1.1, 95%CI:0.9,1.4), ice hockey (HR:1.3, 95%CI: 0.7, 2.6), soccer (HR:0.5, 95%CI:0.3,1.0), and lacrosse (HR:1.0, 95%CI:0.6,1.8).\u003c/p\u003e\u003ch2\u003eConclusion:\u003c/h2\u003e\u003cp\u003eThis is the first study examining SRC risk utilizing repeated time-to-event analyses to identify notable timeframes of SRC incidence. With this method, and a collaborative stakeholder-engaged prospective cohort study, it is possible to strategically direct SRC prevention efforts and advance analytic approaches, which was identified as a priority for future research at the most recent Concussion in Sport Group (CISG) meeting.\u003c/p\u003e","manuscriptTitle":"Use of Time-to-Event Analyses to Identify Concussion Prevention Opportunities During Athletic Seasons: Findings from The Ivy League-B1G Ten Epidemiology of Concussion Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-06 19:23:22","doi":"10.21203/rs.3.rs-7633996/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"384e611b-6748-4e3c-8c7a-3868b9275120","owner":[],"postedDate":"October 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-15T01:08:35+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-06 19:23:22","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7633996","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7633996","identity":"rs-7633996","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}