• BU-Led Study: CTE May Occur without Concussions, Boston University media release, (January 2018). A new BU-led study suggests that chronic traumatic encephalopathy (CTE) is caused by head injuries, not by concussions. The research explains why 20 percent of athletes who exhibited the early stages of the progressive brain illness postmortem never had a diagnosed concussion.
• Explainer: What is concussion? University of Sydney, (22 June 2017). Dr Adrian Cohen from the University of Sydney explains what causes a concussion and how to best prevent them.
• New tech at UC to spearhead fight against concussion, University of Canberra media release, (6 April 2018). Researchers at the University’s Research Institute for Sport and Exercise (UCRISE) will use a brand-new balance assessment device to comprehensively evaluate athletes with suspected concussion.

• Guidelines for diagnosing and managing pediatric concussion: Recommendations for schools and/or community sports organisations/centres, first edition, Ontario Neurotrauma Foundation, Canada, (June 2014). This document is intended to guide the diagnosis and management of pediatric concussion in children and adolescents age 5 to 18 years.
• Sports-Related Concussions in Youth: Improving the Science, Changing the Culture, Graham R, Rivara F, Ford M, and Spicer C (Editors), National Academy Press, (2013). The Institute of Medicine and National and the Research Council (NRC) in the United States convened the Committee on Sports-Related Concussion to review the available literature on concussions within the context of developmental neurobiology, specifically relating to the causes of concussions, their relationship to impacts to the head or body during sports, the effectiveness of protective devices and equipment, screening for and diagnosis of concussions, their treatment and management, and their long-term consequences. Specific topics included in this report:
  • the acute, subacute, and chronic effects of single and repetitive concussive and non-concussive head impacts on the brain;
  • risk factors for sports concussions, post-concussion syndrome, and chronic traumatic encephalopathy;
  • the spectrum of cognitive, affective, and behavioral alterations that can occur during acute, subacute, and chronic posttraumatic phases;
  • physical and biological triggers and thresholds for injury;
  • the effectiveness of equipment and sports regulations in preventing injury;
  • hospital- and non-hospital-based diagnostic tools; and
  • treatments for sports concussions.

• A review of concussion diagnosis and management in Australian professional sporting codes, Premkumar Gunasekaran,Christopher Hodge, Alan Pearce, et.al., The Physician and Sportsmedicine, Volume 48(1), (2020). The purpose of this study was to explore the publicly available concussion guidelines of the major Australian sporting codes with an aim to identify potential opportunities to develop a national sporting consensus. Twelve sites were visited. There was consensus between many of the sporting organizations in terms of concussion definition, removal of play and sideline testing protocols. A step-wise return-to-play protocol was prevalent across most sports. A number of sporting sites however did not have readily available information.
• Normative Data Set of SWAY Balance Mobile Assessment in Pediatric Athletes, Anderson, Stevi L., Gatens, Dustin, Glatts, Colette. Russo, Stephen A., Clinical Journal of Sports Medicine, Volume 29(5), pp.413-420, (September 2019). Normative scores are described, with results stratified into 4 age groups (5-9, 10-12, 13-17, and 18 years old). Balance scores, overall and within each individual stance score, improved with the age of the participants. Sex effects on balance were only seen in single-leg stances, with females outperforming males. Reaction time was found to be faster in males and improved with age, peaking at 13 to 17 years old and slowing in 18-year-olds.
• Performance Times for the King-Devick Test in Children and Adolescents, Gubanich, Paul J., Gupta, Resmi, Slattery, Eric, Logan, Kelsey, Clinical Journal of Sports Medicine , Volume 29(5), pp.374-378, (September 2019). Four hundred eighty-three participants were included in the final analysis, which included 60.5% girls (n = 292) and 39.5% boys (n = 191). The KD test performance varied by age with a steady decrease in test time yearly from 8 years through 14 years of age, where some plateauing occurred. Baseline scores changed approximately 31 seconds over ages 8 to 18. Analysis of variance results revealed a strong effect of age on overall mean KD time. The KD test performance was not associated with sex or other studied concussion risk factors or comorbid conditions.
• The King–Devick test is not sensitive to self-reported history of concussion but is affected by English language skill, Tracey J. Dicksona, Gordon Waddingtona, F. Anne Terwielb, Lisa Elkington, Journal of Science and Medicine in Sport, Volume 22(Supplement 1), pp.S34-S38, (August 2019). For subjects whose first language is not English, such as in many snowsport resorts, the K–D test may need to be conducted in a person’s native language to provide a valid assessment based upon the time to complete the task.
• What HIRTS athletes? Establishing a unified public policy understanding of Head Impact-Related Trauma in Sport, Jason Chung and Amanda Zink, Journal of Public Health Policy, Volume 40, pp.393–409, (2019). The authors propose a ‘HIRTS framework’ to advance public policy pertaining to head impacts and their effects. Given the scientific ambiguities regarding the definition, diagnosis, and markers of concussion and resulting complications, we encourage international policymakers, clinicians, and public health officials to adopt the following working definitions and concomitant policy recommendations to safeguard athletes’ health and optimize tracking efforts, public education, funding, and government services.
• Sports-related concussion (SRC) assessment in road cycling: a systematic review and call to action, Elliott J, Anderson R, Collins S, et al, BMJ Open Sport and Exercise Medicine, Volume 5(1), (2019). Road cycling poses unique challenges for the assessment of SRC. This review illustrates the lack of published evidence to advise effective means of SRC assessment within road cycling. The Union Cycliste Internationale (UCI) regulations advise the use of SCAT-5 for concussion assessment but this tool is impractical, requiring modification for use in road cycling. We would like to call on the UCI to hold a consensus meeting to establish an evidence-based SRC assessment protocol and return-to-riding protocol for road cycling.
• A systems approach to understanding the identification and treatment of sport-related concussion in community rugby union, Amanda Clacy, Natassia Goode, Rachael Sharman, et.al., Applied Ergonomics, Volume 80, pp.256-264, (October 2019). Through an online survey, 118 members of the amateur (community) rugby union system were asked about their role-specific concussion management responsibilities and strategies. Respondents included players, parents, medics, coaches, club managers, administrators, and volunteers. This study illustrated that the current challenges in the identification and treatment of rugby-related concussion in community sport may be due to role/responsibility confusion and possible overreliance on field-side medics. These findings offer insight into the possible limitations of the current concussion management guidelines and may offer empirically based direction for future revisions.
• International consensus definitions of video signs of concussion in professional sports, Gavin A Davis, et.al., British Journal of Sports Medicine, Volume 53(20), pp.1264-1267. (2019). Respondents representing seven sporting bodies (Australian Football League, Cricket Australia, Major League Baseball, NFL, NHL, National Rugby League, World Rugby) reached consensus on eight video signs of concussion. Thirteen representatives from the seven professional sports ranked the definition components. Consolidation and refinement of the video signs and their definitions resulted in consensus definitions for six video signs of possible concussion: lying motionless, motor incoordination, impact seizure, tonic posturing, no protective action—floppy and blank/vacant look.
• International study of video review of concussion in professional sports, Gavin A Davis, et.al., British Journal of Sports Medicine, Volume 53(20), pp.1299-1304. (2019). Six sports with specific diagnostic criteria and definitions for signs of concussion identified on video review participated in this study (Australian football, American football, world rugby, cricket, rugby league and ice hockey). Video signs common to all sports include lying motionless/loss of responsiveness and motor incoordination. The video signs considered by the majority of sports as most predictive of a diagnosis of concussion include motor incoordination, impact seizure, tonic posturing and lying motionless. Regulatory requirements, sideline availability of video, medical expertise of video reviewers and use of spotters differ across sports and geographical boundaries. By and large, these differences reflect a pragmatic approach from each sport, with limited underlying research and development of the video review process in some instances.
• Diagnosis and Management of Mild Traumatic Brain Injury in Children: A Systematic Review. Angela Lumba-Brown, Keith Owen Yeates, Kelly Sarmiento, et al., JAMA Pediatrics, Volume 172(11), (November 2018). This systematic review was used to develop an evidence-based clinical guideline for the diagnosis and management of pediatric mTBI. While an increasing amount of research provides clinically useful information, this systematic review identified key gaps in diagnosis, prognosis, and management.
• The accuracy and reproducibility of video assessment in the pitch-side management of concussion in elite rugby. Fuller, G.W.; Kemp, S.P.T.; Raftery, M., Journal of Science and Medicine in Sport, Volume 20(3), March 2017, p.246.
• Concussion Baseline Testing: Preexisting Factors, Symptoms, and Neurocognitive Performance. Cottle, Jordan E.; Hall, Eric E.; Patel, Kirtida; Barnes, Kenneth P.; Ketcham, Caroline J., Journal of Athletic Training, Volume 52(2), (February 2017), p.77
• King-Devick Performance Following Moderate and High Exercise Intensity Bouts, Rist, Billymo; Cohen, Adrian; and Pearce, Alan J., International Journal of Exercise Science, Volume 10(4), pp.619 - 628, (2017). Using a randomized crossover design, this study aimed to compare the effect of two intensities of exercise on K-D performance. Twenty males (21.2 ± 1.9 years) completed the K-D test prior to and after 15 min of either moderate (65% of age-predicted maximal heart rate) and high intensity (80% of age-predicted maximal heart rate) exercise bouts, separated by one week. Significant differences were found in working heart rate and ratings of perceived exertion consistent with exercise intensities. K-D performance did not change after moderate exercise, however a significant improvement (5.4%) was observed after high intensity exercise. Based upon these findings, it appears that high intensity exercise can influence test performance and administrators of the test need to be aware of the arousal state a player is prior to K-D test administration to ensure objective measurement.
• Observational Review and Analysis of Concussion: a Method for Conducting a Standardized Video Analysis of Concussion in Rugby League, Andrew J. Gardner, Christopher R. Levi, and Grant L. Iverson, Sports Medicine Open, (December 2017). The aim of this study was to evaluate whether independent raters reliably agreed on the injury characterization when using a standardized observational instrument to record video footage of National Rugby League (NRL) concussions. There appears to be value in expert raters, but less value for naive raters, in using the new Observational Review and Analysis of Concussion (ORAC) Form. The ORAC Form has high inter-rater agreement for most data elements, and it can be used by expert raters evaluating video footage of possible concussion in the NRL.
• Usefulness of Video Review of Possible Concussions in National Youth Rugby League. Gardner, Andrew J.; Kohler, Ryan M. N.; Levi, Christopher R.; Iverson, Grant L., International Journal of Sports Medicine, Volume 38(1), (2017), pp.71-75
• Utility of providing a concussion definition in the assessment of concussion history in former NFL players. Michael L. Alosco, Johnny Jarnagin, Yorghos Tripodis, Brett Martin, Christine Chaisson, Christine M. Baugh, Alcy Torres, Christopher J. Nowinski, Robert C. Cantu and Robert A. Stern, Brain Injury, Vol. 31(8), (2017), pp. 1116-1123.
• Concussed or Not? An Assessment of Concussion Experience and Knowledge Within Elite and Semiprofessional Rugby Union. Mathema, Prabhat; Evans, Daniel; Moore, Isabel S.; Ranson, Craig; Martin, Rhodri, Clinical Journal of Sport Medicine, Volume 26(4), (July 2016), p320
• Measurement Error in the Immediate Postconcussion Assessment and Cognitive Testing (ImPACT): Systematic Review. Alsalaheen, Bara; Stockdale, Kayla; Pechumer, Dana; Broglio, Steven P., Journal of Head Trauma Rehabilitation, Volume 31(4), (July/August 2016), pp.242-251.
• Neuropsychological Testing in Mild Traumatic Brain Injury: What to Do When Baseline Testing Is Not Available. Arnett, Peter; Meyer, Jessica; Merritt, Victoria; Guty, Erin, Sports Medicine and Arthroscopy Review, Volume 24(3), (September 2016), pp.116-122.
• Player and parent concussion knowledge and awareness in youth Australian Rules Football. Hecimovicha, Mark; Kingb, Doug; Maraisc, Ida, Sport Journal, (1 April 2016).
• Reference values for the balance error scoring system in adolescents. Alsalaheen, Bara; McClafferty, Adam; Haines, Jamie; Smith, Laura; Yorke, Amy. Brain Injury, Volume 30(7), (April 2016), pp.914-918.
• The sensitivity and specificity of clinical measures of sport concussion: three tests are better than one, Resch J, Brown C, Schmidt J, Macciocchi S, Blueitt D, Callum CM and Ferrara M, BMJ Open Sport and Exercise Medicine, Volume 2, Issue 1, (19 January 2016).
• Using video analysis for concussion surveillance in Australian football, Makdissi M and Davis G, Journal of Science and Medicine in Sport, Volume 19, Issue 12 (2016).
• A preliminary video analysis of concussion in the National Rugby League, Andrew J. Gardner, Grant L. Iverson, Tanya N. Quinn, Michael Makdissi, Christopher R. Levi, Sandy R. Shultz, Brain Injury , Volume 29(10), (June 2015). Most concussions (83%) occurred during a high tackle, and all injured ball carriers were hit high. Loss of consciousness was observed in 30% of cases. Common observable signs of injury included clutching of the head, balance problems or wobbly legs and a blank or vacant state. There were no post-concussive seizures. All players with loss of consciousness were removed from play. However, only half of the total sample was removed from play and one athlete who was removed returned to play in the same match. Of the players who were removed from play, the large majority returned the following week. Illegal play accounted for 25% of all concussions.
• An evidence-based discussion of heading the ball and concussions in high school soccer, Comstock D, Currie D, Pierpoint L, Grubenhoff A and Fields S, JAMA Pediatrics, (13 July 2015). Concerns have been raised regarding the safety of soccer ball heading (when an athlete attempts to play the ball in the air with his or her head) given the rise in concussion rates, with some calling for a ban on heading among soccer players younger than 14 years. This retrospective analysis used longitudinal surveillance data collected from 2005-2014 in US high schools, for both boys and girls. The analysis indicated that although heading the ball is commonly associated with concussions, the most frequent mechanism was athlete-to-athlete contact.
• Concussion in sport: Conceptual and ethical issues, McNamee M, Partridge B and Anderson L, Kinesiology Review, Volume 4, Issue 2 (2015). This article discusses concussion from philosophical, bioethical, and sports ethical perspectives. The authors identify conceptual differences in approaches to definition and therefore diagnosis of concussion. They also critically review similarities and differences in the leading consensus statements that guide the treatment of concussion diagnosis and treatment in sports. Finally, they present a series of ethical problems, including issues that relate to intervention in the lives of athletes in order to prevent harm, conflicting and competing interests, and confidentiality.
• Detection of concussion using cranial accelerometry, Auerbach P, Baine J, Schott M, Greenhaw A, Acharya M and Smith W, Clinical Journal of Sport Medicine, Volume 25, Number 2 (2015).
• The diagnostic utility of clinical tests for differentiating between cervicogenic and other causes of dizziness after a sports-related concussion: An international Delphi study, Reneker J, Moughiman M and Cook C, Journal of Science and Medicine in Sport, Volume 18, Number 4 (2015). Dizziness after a sports-related concussion is very common and is associated with prolonged recovery. This study was conducted to identify proper clinically administered tests and measures that are useful in differentiating between cervicogenic and other causes of dizziness after a sports-related concussion. A group of 25 experts in the field of concussion and dizziness, representing several medical disciplines, assessed ten clinical tests. Seven of these tests achieved no consensus among the experts. The clinical tests identified as having strong clinical utility are tests used to identify dizziness originating from the vestibular or central nervous system. No clinical tests specific for the cervical region achieved consensus. Expert opinion from different medical professions and even within professions was widely divergent regarding the utility of clinical tests to assess cervical dysfunction.
• Assessing Postural Stability in the Concussed Athlete: What to Do, What to Expect, and When, Ruhe A, Fejer R, Gänsslen A and Klein W, Sports Health: A Multidisciplinary Approach, Published online (25 June 2014).
• Assessment, management and knowledge of sport-related concussion: Systematic review, King D, Brughelli M, Hume P and Gissane C, Sports Medicine, Volume 44, Issue 4 (2014). Concussion is often hard to recognise and diagnose. Initial sideline assessment via the Sports Concussion Assessment Tool 3 (SCAT3), Child-SCAT3 or King-Devick test should be undertaken to identify athletes with concussion as part of a continuum of assessment modalities and athlete management strategies. Sports medicine practitioners should be cognisant of the definition, extent and nature of concussion, and should work with coaches, athletes and trainers to identify and manage concussions. The most common reason for variations in management of concussion is lack of awareness of, and confusion about, the many available published guidelines for concussion. Future research should focus on better systems and tools for recognition, assessment and management of concussion. Sport participants’ knowledge of concussion should be evaluated more rigorously, with interventions for sports where there is little knowledge of recognition, assessment, and appropriate management of concussion.
• The evaluation and management of acute concussion differs in young children, Davis G and Purcell L, British Journal of Sports Medicine, Volume 48, Issue 2 (2014), published online (23 April 2013). The aim of this study is to review the current literature on concussion assessment at the sideline and during recovery stages, especially in the age group 5–15 years, and the management of concussion in children and adolescents. The study found that no single paediatric concussion assessment tool has been validated for use from sideline through to all stages of recovery. A young child is physically, cognitively and emotionally very different from an adult, and requires the use of a different set of tools for the diagnosis, recovery-assessment and management of concussion. Age-specific, validated diagnostic tools are required, and management of concussion in children should focus attention on return to learn before considering return to play.
• The King-Devick test as a concussion screening tool administered by sports parents (abstract), Leong D, Balcer L, Galetta S, Liu Z and Master C, The Journal of Sports Medicine and Physical Fitness, Volume 54, Number 1, pp.70-77 (2014).
• Objective Functional Assessment After a Head Injury Using Movement and Activity in Physical Space Scores: A Case Report, Farnsworth J 2nd, McElhiney D, David S, Sinha G and Ragan B, Journal of Athletic Training, Epub ahead of print (19 May 2014).
• Translating guidelines for the diagnosis and management of sports-related concussion into practice, Donaldson A, Newton J, McCrory P, White P, Davis G, Makdissi M and Finch C, American Journal of Lifestyle Medicine , published online (19 June 2014).
• Sport and team differences on baseline measures of sport-related concussion, Zimmer A, Piecora K, Schuster D and Webbe F, Journal of Athletic Training, Volume 48, Number 5, p659-67 (2013).
• What is the lowest threshold to make a diagnosis of concussion? McCrory P, Meeuwisse W, Echemendia R, Iverson G, Dvorak J and Kutcher J, British Journal of Sports Medicine , Volume 47, Issue 5, p268-271, (2013).

• Concussion in Sport Guidelines – An AIS and AMA Initiative, Dr David Hughes, AIS Chief Medical Officer, Smart Talk Seminar Series, Australian Institute of Sport, Canberra (31 May 2016)
• Sports-related concussion in children and adolescents, Brain Injury Australia Workshop, NSWIS Building, Sydney Olympic Park (13 November 2015)
• Concussion management in community sport - Feature Presentation, Dr Ron Muratore, Chief Medical Officer, National Rugby League, NSW Office for Sport and Recreation, Sports Talks series, (8 October 2014)
• Concussion management in community sport - Club case study, Dennis Lowe, Sports Trainer and Club Official, Penrith Junior Rugby League, Sports Talks (8 October 2014)
• Concussion management in community sport - research, John Searl, Senior Development Manager Regional NSW, ARU, Sports Talks (8 October 2014)
• Traumatic Brain Injury in Athletes: New Concepts, New Dilemmas, James C Puffer MD, Smart Talk Seminar Series, Australian Institute of Sport, Canberra, (16 July 2014)

• Concussion in Sport Australia, Sport Australia, YouTube, (8 October 2018). Every weekend thousands of Australians are concussed while playing sport. Find out how it occurs, how to identify the symptoms and how to treat it. To learn more, visit concussioninsport.gov.au.
• Concussion in Sport Australia: Medical Practitioners, Sport Australia, YouTube, (14 November 2018). Diagnosing concussion can be difficult, even for experienced medical practitioners. Leading sports medicine experts have collaborated to provide contemporary, evidence-based guidelines for the management of concussion in sport.
• Concussion in Sport – Athletes, Australian Institute of Sport, YouTube (20 July 2015). Jayden Warner from the Australian Steelers (National Wheelchair Rugby Team) and Jasmine Simmons (Basketball Australia, Centre of Excellence athlete) share their story on how they managed their concussion. Dr David Hughes (AIS Chief Medical Officer) also provides an important message for all athletes who are suffering with concussion.
• Explainer: What is a concussion? Dr Adrian Cohen, University of Sydney, Sydney Health/Sydney Morning Herald, YouTube, (21 June 2017).
• Scottish Rugby Concussion Study, Scottish Rugby, YouTube, (27 February 2014).
• What happens when you have a concussion? Clifford Robbins, TED-Ed, YouTube, (27 July 2017).
• You can't see a concussion, Sports Medicine Australia, YouTube, (14 March 2016).

• An Investigation of Factors Associated With Head Impact Exposure in Professional Male and Female Australian Football Players, Jonathan Reyes, Biswadev Mitra, Andrew McIntosh, et.al., American Journal of Sports Medicine , (7 April 2020). Playing situations in which players have limited control of the football are a common cause of impacts. Male players sustained a greater exposure to HAEs compared with female players. Female players, however, sustained higher exposure to HAEs than male players during certain skill executions, possibly reflecting differences in skill development. These findings can therefore inform match and skill development in the emerging professional women’s competition of Australian football.
• Examination of sports and recreation-related concussion among youth ages 12–17: results from the 2018 YouthStyles survey, Kelly Sarmiento, Jill Daugherty, Lara DePadilla and Matthew J. Breiding, Brain Injury, Volume 34(3), (February 2020). Forty-three percent of youth surveyed sustained their most recent concussion while playing on a sports team, 21.1% while playing on a community-based team, and 36.0% while engaged in a sport or recreational activity. Nearly half (45.3%) reported having to miss playing sports or participating in physical activity for at least one day; about two in ten (19.7%) reported having to miss time on their phone or computer for at least one day. Despite wide-spread efforts to promote protocols for SRR concussion among youth, a third of participants in this study did not seek medical care and more than half did not miss at least one day of sports or physical activity participation following a concussion.
• Frequency and Magnitude of Game-Related Head Impacts in Male Contact Sports Athletes: A Systematic Review and Meta-Analysis, Jack V. K. Nguyen, James H. Brennan, Biswadev Mitra and Catherine Willmott, Sports Medicine, Volume 49, pp.1575–1583, (2019). Twenty-one studies met the inclusion criteria with 12 conducted on American Football athletes. Six of these studies were included for meta-analysis. At a threshold of 10g, amateur rugby players sustained the most impacts per player per game, followed by amateur Australian Football and collegiate lacrosse athletes. At thresholds of greater than 14.4g, high school American Football athletes sustained between 19 and 24.4 impacts per player per game. Statistically significant heterogeneity was observed among the included studies, and meta-analysis of impact magnitude was limited.
• Incidence of Concussion and Head Impacts in Australian Elite-Level Male and Female Cricketers After Head Impact Protocol Modifications, Thomas Hill, John Orchard, and Alex Kountouris, Sports Health, Volume 11(20), pp.180-185, (March-April 2019). The rate of concussion in cricket is higher than previously appreciated; however, the majority of patients recovered quickly, and players generally did not miss much playing time as a result. The institution of concussion policies after head impact, including player substitution, appears to have had an effect on increasing reporting of symptoms, resulting in an increase in diagnosis of concussion.
• Lifetime prevalence of self-reported concussion among adolescents involved in competitive sports: A national U.S. study, Philip Veliz, James T. Eckner, Jennifer Zdroik, and John E. Schulenberg, Journal of Adolescent Health , Volume 64(2), pp.272-275, (February 2019). Adolescents who participated in baseball, basketball, football, gymnastics, ice hockey, lacrosse, soccer, track, weightlifting, and „other sports“ had greater odds of reporting multiple diagnosed concussions compared to peers not participating in these sports. Adolescents who participated in tennis had lower odds of reporting any diagnosed concussion or multiple concussions. Females who participated in gymnastics, soccer, and swimming showed a stronger association in reporting a diagnosed concussion when compared to males who participated in these same types of sports.
• The epidemiology of concussion in professional rugby union in Ireland, Matthew Cosgrave and Sean Williams, Physical Therapy in Sport, Volume 35, pp.99-105, (January 2019). Highlights of this study: Match concussion incidence rate was 18.4/1000 player-match-hours; Overall burden of match concussion was 5 days absence per team per match; Only 13% of players return to play at the minimum recommended recovery time of 6 days; Time loss increases with number of symptoms and symptom severity score; The tackle was responsible for 70% of concussions (tackler 41%; ball carrier 29%).
• Clinicopathological Evaluation of Chronic Traumatic Encephalopathy in Players of American Football. Mez J, Daneshvar DH, Kiernan PT, Abdolmohammadi B, Alvarez VE, Huber BR, et.al., JAMA, 318(4), (July 2017), pp.360–370. In a convenience sample of 202 deceased players of American football from a brain donation program, CTE was neuropathologically diagnosed in 177 players across all levels of play (87%), including 110 of 111 former National Football League players (99%).
• The incidence of concussion in youth sports: a systematic review and meta-analysis, Pfister T, Pfister K, Hagel B, Ghali W and Ronksley P, British Journal of Sports Medicine, Volume 50, Issue 5 (2016). This is a systematic review and meta-analysis of studies assessing the incidence of concussion in youth athletes in the United States. Specifically, the authors estimate the overall risk of concussion in youth sports and compare sport-specific estimates of concussion risk. Of the 698 studies reviewed for eligibility, 23 met the inclusion criteria. The overall risk of concussion (12 sports, males and females 18 years and younger) was estimated at 0.23 incidence rate per 1000 athlete exposures. The three sports with the highest incidence rates were rugby (4.18), ice hockey (1.20) and American football (0.53), and the lowest occurred in volleyball, baseball and cheerleading at 0.03, 0.06 and 0.07, respectively. Quality of the included studies varied, with the majority of studies not reporting age and gender-specific incidence rates or an uniform operational definition for concussion.
• Trends in Sports- and Recreation-Related Traumatic Brain Injuries Treated in US Emergency Departments: The National Electronic Injury Surveillance System-All Injury Program (NEISS-AIP) 2001-2012. Coronado, Victor G.; Haileyesus, Tadesse; Cheng, Tabitha A. et.al., Journal of Head Trauma Rehabilitation, Volume 30(3), (May/June 2015), pp.185–197. The rates of ED-treated Sports- and recreation-related traumatic brain injuries (SRR-TBIs) increased during 2001-2012, affecting mainly persons aged 0 to 19 years and males in all age groups. Increases began to appear in 2004 for females and 2006 for males. Activities associated with the largest number of TBIs varied by sex and age. Reasons for the reported increases in ED visits are unknown but may be associated with increased awareness of TBI through increased media exposure and from campaigns, such as the Centers for Disease Control and Prevention's Heads Up. Prevention efforts should be targeted by sports and recreational activity, age, and sex.
• A preliminary video analysis of concussion in the National Rugby League, Gardner AJ, Stanwell P, Levi CR, et al., Brain Injury, Volume 29(10), pp.1182-1185, (2015). Most concussions (83%) occurred during a high tackle, and all injured ball carriers were hit high. Loss of consciousness was observed in 30% of cases. Common observable signs of injury included clutching of the head, balance problems or wobbly legs and a blank or vacant state. There were no post-concussive seizures. All players with loss of consciousness were removed from play. However, only half of the total sample was removed from play and one athlete who was removed returned to play in the same match. Of the players who were removed from play, the large majority returned the following week. Illegal play accounted for 25% of all concussions.
• Comparing severe injuries by sex and sport in collegiate-level athletes: A descriptive epidemiological study, Hurtubise J, Beech C and Macpherson A, International Journal of Athletic Therapy and Training, Volume 20, Number 4 (2015).
• Motivations for underreporting suspected concussion in college athletics, Davies S and Bird B, Journal of Clinical Sport Psychology, Volume 9, Number 2 (2015).
• Sports-related concussion in helmeted vs unhelmeted athletes: Who fares worse? Zuckerman S, Lee Y, Odom M, Forbes J, Solomon G and Sills A, International Journal of Sports Medicine, Volume 36, Number 5 (2015).
• A Systematic Review and Meta-Analysis of Concussion in Rugby Union. Andrew Gardner, Grant Iverson, W. Huw Williams, Stephanie Baker, Peter Stanwell, Sports Medicine, Volume 44(12), (December 2014), pp.1717-1731. Concussion is a common injury sustained and reported in match play and to a lesser extent during practice by Rugby Union players. Based on the available published data, there appears to be a variation in risk of concussion across level of play, with the sub-elite level having the greatest incidence of injury.
• Is There Chronic Brain Damage in Retired NFL Players? Neuroradiology, Neuropsychology, and Neurology Examinations of 45 Retired Players, Casson I, Viano D, Haacke E, Kou Z and LeStrange D, Sports Health: A Multidisciplinary Approach, (25 June 2014).
• Sport-related concussions in New Zealand: A review of 10 years of Accident Compensation Corporation moderate to severe claims and costs, King D, Gissane C, Brughelli M, Hume P and Harawira J, Journal of Science and Medicine in Sport , Volume 17, Issue 3 (2014). This paper provides an overview of the epidemiology of sport-related concussion and associated costs in New Zealand requiring medical treatment from 2001 to 2011 in seven sports codes. The study found that injury claims for concussion were only 6.4% of total claims, but they accounted for 79.1% of total costs. Sport-related concussions may be infrequent, but the related economic costs associated with more serious sport-related concussion can be high.
• Increasing incidence of sports related concussion hospitalisations in Victoria, Australia, Finch C, Clapperton A and McCrory P, Medical Journal of Australia, Volume 198, p1-4, (2013). This research describes trends in hospitalisation for sport-related concussion. Data was evaluated from all Victorian hospital admissions from 2002-03 to 2010-11 for patients, age 15 years and above, diagnosed with concussion and an activity code indicating sport. The frequency and participation-adjusted rate of hospitalisation for sport-related concussion, both overall and across several sports, increased significantly over the 9 years. These findings, along with high levels of public concern, make prevention of head injury in sport a population health priority in Australia.
• Injury risk is different in team and individual youth sport. Theisen D, Frisch A, Malisoux L, Urhausen A, Croisier J and Seil R, Journal of Science and Medicine in Sport, Volume 16(3), (2013). Injury incidence was significantly higher in team compared with individual sports, as a result of a higher incidence of both traumatic, and overuse injuries. The number of competitions per 100 days was significantly higher in team sports, whereas the number of intense training sessions per 100 days was significantly lower. In team sports, the number of competitions per 100 days was positively associated with injuries, while in individual sports the number of competitions per 100 days had a protective effect.

Sports-Related Concussions in Youth: Improving the Science, Changing the Culture, Graham R, Rivara F, Ford M, and Spicer C (Editors), National Academy Press, (2013). The Institute of Medicine and National and the Research Council (NRC) in the United States convened the Committee on Sports-Related Concussion to review the available literature on concussions within the context of developmental neurobiology, specifically relating to the causes of concussions, their relationship to impacts to the head or body during sports, the effectiveness of protective devices and equipment, screening for and diagnosis of concussions, their treatment and management, and their long-term consequences. Specific topics included in this report:

• the acute, subacute, and chronic effects of single and repetitive concussive and non-concussive head impacts on the brain;
• risk factors for sports concussions, post-concussion syndrome, and chronic traumatic encephalopathy;
• the spectrum of cognitive, affective, and behavioral alterations that can occur during acute, subacute, and chronic posttraumatic phases;
• physical and biological triggers and thresholds for injury;
• the effectiveness of equipment and sports regulations in preventing injury;
• hospital- and non-hospital-based diagnostic tools; and
• treatments for sports concussions.

• Reducing risk of head injury in youth soccer: An extension of behavioral skills training for heading, Laura M. Quintero James W. Moore M. Garrett Yeager, et.al., Journal of Applied Behavior Analysis , Volume 53(1), pp.237-248, (Winter 2020). There is currently limited research on an effective teaching method to improve safe heading technique. In the current study, Behavior Skills Training (BST) was evaluated as a method to teach correct heading techniques to youth soccer players. BST increased the percentage of correct steps for each player based on a task analysis of heading. Based on social validity questionnaires administered to players and the coach, BST was rated as an acceptable form of training. After the final training session, experienced coaches rated each player as having improved from baseline to training.
• What they know and who they are telling: Concussion knowledge and disclosure behaviour in New Zealand adolescent rugby union players, Danielle M. Salmon,Jody Mcgowan,S. John Sullivan, et.al., Journal of Sport Sciences, (8 April 2020). The purpose of this study was to survey high school rugby players from a range of ethnic, geographic and socioeconomic backgrounds in New Zealand (NZ) to gain an understanding of concussion knowledge, awareness of NZ Rugby’s (NZR) guidelines and attitudes towards reporting behaviours. Male and female high school rugby players (n= 416) from across NZ were surveyed. The findings indicated that 69% of players had sustained a suspected concussion, and 31% had received a medical diagnosis of concussion. 63% of players indicated they were aware of NZR’s guidelines. Māori and Pasifika players were less likely to be aware of the guidelines compared to NZ European. Guideline awareness was significantly higher for those from high decile schools when compared to low; however, when ethnicity and school locations were controlled for this became non-significant. The coach was the key individual for the provision of concussion information and disclosure of symptoms for players.
• The Influence of Psychological Factors on the Incidence and Severity of Sports-Related Concussions: A Systematic Review, Lily N. Trinh, Symone M. Brown, Mary K. Mulcahey, American Journal of Sports Medicine, (8 November 2019). The initial search identified 1195 articles. Ten studies met our inclusion criteria and were included in our analysis. Factors such as meanness, aggression, and psychoticism were associated with an increased incidence of SRCs. Baseline traits of irritability, sadness, nervousness, and depressive symptoms were associated with worse symptomatology after SRCs. In young athletes, preexisting psychiatric illnesses, family history of psychiatric illness, and significant life stressors were associated with an increased risk of developing postconcussion syndrome after SRCs.
• Insomnia and daytime sleepiness: risk factors for sports-related concussion, Adam C. Raikes, Amy Athey, Pamela Alfonso-Miller, et.al., Sleep Medicine, Volume 58, pp.66-74, (June 2019). Insomnia and daytime sleepiness are independently associated with increased sports-related concussion risk. More completely identifying bidirectional relationships between concussions and sleep requires further research. Clinicians and athletes should be cognizant of this relationship and take proactive measures – including assessing and treating sleep-disordered breathing, limiting insomnia risk factors, improving sleep hygiene, and developing daytime sleepiness management strategies – to reduce sports-related concussion risk and support overall athletic performance.
• Effectiveness of the US Centers for Disease Control and Prevention HEADS UP coaches’ online training as an educational intervention, Jill Daugherty, Lara DePadilla, Kelly Sarmiento, Health Education Journal , Volume 78(7), (May 2019). HEADS UP training improved coaches’ knowledge on select topics and helped them feel more comfortable about responding to concussion among their athletes. This study provides insight into how to better focus future HEADS UP concussion health education efforts to fit coaches’ informational needs.
• What the research says about concussion risk factors and prevention strategies for youth sports: A scoping review of six commonly played sports, Dana Waltzman and Kelly Sarmiento, Journal of Safety Research , Volume 68, pp.157-172, (February 2019). This scoping review summarizes current research on concussion risk factors and primary prevention strategies in specific sports (football, ice hockey, soccer, lacrosse, basketball, and wrestling) focused on youth athletes and identifies research gaps to help inform future efforts.
• Musculoskeletal Injury Risk After Sport-Related Concussion: A Systematic Review and Meta-analysis, April L. McPherson, et.al., American Journal of Sports Medicine, Volume 47(7), (2019). Eight studies met inclusion criteria for meta-analysis. Meta-analysis results indicated that athletes who had a concussion had 2 times greater odds of sustaining a MSK injury than athletes without concussion. In addition, athletes with concussion demonstrated a higher incidence of MSK injury after return to sport compared with nonconcussed athletes. Further analysis showed that both male and female athletes with concussion were at an increased risk of MSK injury compared with their respective same-sex, nonconcussed controls. Based on the evidence of higher risk of MSK injuries after concussion, standard clinical assessments for athletes with concussion should include not only physical symptoms and cognitive function before return to sport but also neuromuscular risk factors associated with increased risk for MSK injuries.
• Age of first exposure to American football and long-term neuropsychiatric and cognitive outcomes. M L Alosco, A B Kasimis, J M Stamm, et.al., Translational Psychiatry, Volume 7, (19 September 2017). This research examined the association between age of first exposure (AFE) to football and behavior, mood, and cognition in a large cohort of former amateur and professional football players. The sample included 214 former football players without other contact sport history. Results indicate that there was no interaction between AFE and highest level of play. Younger AFE to football, before age 12 in particular, was associated with increased odds for impairment in self-reported neuropsychiatric and executive function in 214 former American football players. Longitudinal studies will inform youth football policy and safety decisions.
• Convergence insufficiency identifies athletes at risk of prolonged recovery from sport-related concussion, DuPrey K, Webner D, Lyons A, Kucuk C, Ellis J and Cronholm P, The American Journal of Sports Medicine, (16 May 2017).
• Development, implementation and assessment of a concussion education programme for high school student-athletes, Caron J, Rathwell S, Delaney J, Johnston K, Ptito A and Bloom G, Journal of Sports Sciences , (17 January 2017).
• Development of the Sports Organization Concussion Risk Assessment Tool (SOCRAT). Yeung, A.; Munjal, V.; Virji-Babul, N. Brain Injury. Volume 31(4), pp.542-549, (February 2017).
• A systematic review of education programmes to prevent concussion in rugby union. Fraas, Michael R.; Burchiel, Jessica, European Journal of Sport Science, Vol. 16(8), pp.1212, (November 2016).
• Player and parent concussion knowledge and awareness in youth Australian Rules Football. Hecimovicha, Mark; Kingb, Doug; Maraisc, Ida, Sport Journal, (1 April 2016).
• An evidence-based discussion of heading the ball and concussions in high school soccer, Comstock D, Currie D, Pierpoint L, Grubenhoff A and Fields S, JAMA Pediatrics, (13 July 2015). Concerns have been raised regarding the safety of soccer ball heading (when an athlete attempts to play the ball in the air with his or her head) given the rise in concussion rates, with some calling for a ban on heading among soccer players younger than 14 years. This retrospective analysis used longitudinal surveillance data collected from 2005-2014 in US high schools, for both boys and girls. The analysis indicated that although heading the ball is commonly associated with concussions, the most frequent mechanism was athlete-to-athlete contact.
• Sports-related concussion in helmeted vs unhelmeted athletes: Who fares worse? Zuckerman S, Lee Y, Odom M, Forbes J, Solomon G and Sills A, International Journal of Sports Medicine, Volume 36, Number 5 (2015).
• Assessment, management and knowledge of sport-related concussion: Systematic review, King D, Brughelli M, Hume P and Gissane C, Sports Medicine, Volume 44, Issue 4 (2014). Concussion is often hard to recognise and diagnose. Initial sideline assessment via the Sports Concussion Assessment Tool 3 (SCAT3), Child-SCAT3 or King-Devick test should be undertaken to identify athletes with concussion as part of a continuum of assessment modalities and athlete management strategies. Sports medicine practitioners should be cognisant of the definition, extent and nature of concussion, and should work with coaches, athletes and trainers to identify and manage concussions. The most common reason for variations in management of concussion is lack of awareness of, and confusion about, the many available published guidelines for concussion. Future research should focus on better systems and tools for recognition, assessment and management of concussion. Sport participants’ knowledge of concussion should be evaluated more rigorously, with interventions for sports where there is little knowledge of recognition, assessment, and appropriate management of concussion.
• Engagement by education for action: Recommendations for educational interventions to prevent concussion in sport, Gleadhill S, James D, Maher-Sturgess S and Lee J, Journal of Fitness Research, Volume 3, Issue 3 (December 2014). The aim of this review was to identify current best practice educational initiatives and to determine if education alone is an effective prevention strategy for decreasing the rate of sports concussion. In addition, the authors identify research gaps and make recommendations for future study.
• Intention to use sport concussion guidelines among community-level coaches and sports trainers, Newton J, White P, Ewing M, Makdissi M, Davis G, Donaldson A, Sullivan S, Seward H and Finch C, Journal of Science and Medicine in Sport, Volume 17, Number 5, p469-473, (2014).
• Knowledge about sports-related concussion: is the message getting through to coaches and trainers?, White P, Newton J, Makdissi M, Sullivan J, Davis G, McCrory P, Donaldson A, Ewing M and Finch C, British Journal of Sports Medicine , Volume 48, Issue 2 (2014), published online (16 September 2013). This study aimed to assess whether key messages within concussion guidelines are reflected in the knowledge of coaches and sports trainers working in community sport. Data was gathered from an online knowledge survey that was widely promoted across Australia from May to August 2012 that targeted community coaches and trainers in Australian Football and Rugby League. General concussion knowledge did not differ across the football codes and sports trainers had higher knowledge scores than did coaches. There were no significant differences in either concussion symptoms or concussion management knowledge across codes or team roles. Over 90% of respondents correctly identified five of the eight key signs or symptoms of concussion, but fewer than 50% recognised the increased risk of another concussion following an initial concussion. Most respondents incorrectly believed or were uncertain that scans typically show damage to the brain after a concussion occurs. Fewer than 25% recognised, and more than 40% were uncertain that younger players typically take longer to recover from concussion than adults. The key messages from published concussion management guidelines have not fully reached community sports coaches and sports trainers and this outcome needs to be redressed.
• Neck strengthening recommendations for concussion risk reduction in youth sport, Caswell S, York M, Ambegaonkar J, Caswell A and Cortes N, International Journal of Athletic Therapy and Training, Volume 19, Number 6 (2014). Evidence has shown brain injury to be associated with head accelerations experienced as a result of a biomechanical trauma. Research has influenced equipment design to reduce head acceleration. Research has also suggested that characteristics of adolescents (head–neck segment mass, muscle activity, timing, strength, and stiffness) may be risk factors for concussion. It has been noted that adolescents with a smaller neck circumference and a smaller neck-to-head circumference ratio demonstrated weaker neck strength and an increased risk of sustaining a concussion. This paper briefly reviews the current literature on neck strength training relating to youth populations and provides practical recommendations for low-cost resistance training of neck and cervical musculature in youth athletes.
• Risk factors for sports concussion: an evidence-based systematic review, Abrahams S, McFie S, Patricios J, Posthumus M and September A, British Journal of Sports Medicine, Volume 48, Issue 2 (2014). This evidence-based systematic review provides descriptive analysis of several risk factors for sports concussion. Specifically, athletes with a history of previous sport-related concussions were at a higher risk of sustaining another concussion. In addition to previous concussion, match play increased concussion risk and therefore a good estimate of risk may be established. All other risk factors have a low certainty of association with the risk of concussion. Finally, the devastating effect on quality of life, especially in the athlete’s later years, of debilitating neurological complications such as CTE as a consequence of repetitive concussive head impacts are a concern. Consequently, more high-quality studies are needed to confirm factors which may modulate concussion risk to reduce concussion incidence, improve management of athletes at high risk, and prevent serious health complications in the future.
• Young age as a modifying factor in sports concussion management: What is the evidence? Foley C, Gregory A and Solomon G, Current Sports Medicine Reports, Volume 13, Issue 6 (2014).
• Knowledge, attitude, and concussion-reporting behaviors among high school athletes: a preliminary study, Register-Mihalik J, Guskiewicz K, McLeod T, Linnan L, Mueller F and Marshall S, Journal of Athletic Training, Volume 48, Number 5, pp.645-653 (2013).
• “One Ding to Rule Them All” a proposed new approach to regulating brain injuries in sport, Heshka J and Lines K, International Journal of Sport and Society , Volume 3, Issue 4 (2013). Sport is seemingly dazed and confused, almost as if sustaining a concussion itself, on how to proceed in the regulation and management of brain injuries. Pushed and prodded by doctors and insurers, what has been absent is a consistent and cogent approach, such as the one used by the World Anti-Doping Agency as promulgated in the World Anti-Doping Code. This paper discusses brain injuries, their almost inevitability in contact or collision sports, and proposes a standardised framework for their regulation. What this paper suggests is that if the problem is systemic, cultural and pan-sport, the solution similarly needs to go beyond the explanation that “This is how the game is played.” The problem with the current approach to concussion regulation and management is that despite a number of consensus statements and position papers on concussion management and treatment, there is no consistent trans-sport, global, or even national approach. Instead, each sport takes its own view on what needs to be done and what guidelines should be issued. Indeed, even within what are objectively very similar contact sports, a distinct lack of synchronicity exists.

• Concussion in Sport Guidelines – An AIS and AMA Initiative, Dr David Hughes, AIS Chief Medical Officer, Smart Talk Seminar Series, Australian Institute of Sport, Canberra (31 May 2016)
• Sports-related concussion in children and adolescents, Brain Injury Australia Workshop, NSWIS Building, Sydney Olympic Park (13 November 2015)
• Concussion management in community sport - Feature Presentation, Dr Ron Muratore, Chief Medical Officer, National Rugby League, NSW Office for Sport and Recreation, Sports Talks series, (8 October 2014)
• Concussion management in community sport - Club case study, Dennis Lowe, Sports Trainer and Club Official, Penrith Junior Rugby League, Sports Talks (8 October 2014)
• Concussion management in community sport - research, John Searl, Senior Development Manager Regional NSW, ARU, Sports Talks (8 October 2014)
• Traumatic Brain Injury in Athletes: New Concepts, New Dilemmas, James C Puffer MD, Smart Talk Seminar Series, Australian Institute of Sport, Canberra, (16 July 2014)

• Head Games: how much of you are you willing to lose for a game? Director: Steve James, (2012). (available from Clearinghouse for Sport VIDEO V RC394.C7.1)

• The Role of Nutrition in Sub-Concussion Injury Protection, Ashley Armstrong, SIRCuit, (2 Apri 2020). The goal of this article is to examine nutrition-related strategies that show promise in being protective to the brain in sports that experience a high volume of sub-concussive injuries. Both dietary patterns and nutritional supplementation have shown promise in this area when strategies are adopted both before and after impacts. The article will provide general dietary guidelines and explore specific nutrients and supplements that show strong evidence around neuroprotection.
• The Role of Nutrition in Sport Concussion Recovery, Ashley Armstrong, SIRCuit, (6 November 2019). Although much of the research is still in its infancy, the integration of a safe and low risk nutritional approach may not only be protective, but have the potential to enhance recovery. Outlined below are some key interventions that should be considered in post-sport concussion treatment.

• Guidelines for diagnosing and managing pediatric concussion: Recommendations for schools and/or community sports organisations/centres, first edition, Ontario Neurotrauma Foundation, Canada (June 2014). This document is intended to guide the diagnosis and management of pediatric concussion in children and adolescents age 5 to 18 years.
• Sports-Related Concussions in Youth: Improving the Science, Changing the Culture, Graham R, Rivara F, Ford M, and Spicer C (Editors), National Academy Press, (2013). The Institute of Medicine and National and the Research Council (NRC) in the United States convened the Committee on Sports-Related Concussion to review the available literature on concussions within the context of developmental neurobiology, specifically relating to the causes of concussions, their relationship to impacts to the head or body during sports, the effectiveness of protective devices and equipment, screening for and diagnosis of concussions, their treatment and management, and their long-term consequences. Specific topics included in this report:
  • the acute, subacute, and chronic effects of single and repetitive concussive and non-concussive head impacts on the brain;
  • risk factors for sports concussions, post-concussion syndrome, and chronic traumatic encephalopathy;
  • the spectrum of cognitive, affective, and behavioral alterations that can occur during acute, subacute, and chronic posttraumatic phases;
  • physical and biological triggers and thresholds for injury;
  • the effectiveness of equipment and sports regulations in preventing injury;
  • hospital- and non-hospital-based diagnostic tools; and
  • treatments for sports concussions.

• Concussive Events: Using the Evidence to Guide Physical Therapist Practice, Journal of Orthopaedic and Sports Physical Therapy, Volume 50(4), pp.170-217, (April 2020). The clinical practice guideline published in the April 2020 issue of JOSPT outlines the role of physical therapy examination and management after a concussive event.
• Postconcussion Exertion Evolution Clinical and Behavioral Considerations, Register-Mihalik, Johna K., Callahan, Christine E., Current Sports Medicine Reports, Volume 19(4), pp.151-156, (April 2020). This review will outline recent evidence concerning both rest and exertion postconcussion through the lens of the socioecological model to more rapidly promote policy and practice changes.
• Improving Concussion Care for Athletes with Intellectual Disabilities, Fudge, Jessie, Current Sports Medicine Reports, Volume 19(4), pp.131-132, (April 2020).
• Return to Learn: Academic Effects of Concussion in High School and College Student-Athletes, Acacia Holmes, Zhongxue Chen, Lilian Yahng, David Fletcher, and Keisuke Kawata, Frontiers in Pediatrics, Volume 8(57), (March 2020). Our data indicate that concussions can induce negative symptoms in the academic setting regardless of age. The post-concussion difficulties in academic performance may be a grade-dependent manner, where concussions triggered difficulty in math among high school students and in reading and computer use among college students. It is clear that there is a need for guidelines and accommodations to support students with concussion in academic settings, and the guideline should reflect the age-dependent response to concussions.
• The Effects of Aerobic Exercise on Postconcussion Symptoms in Patients With Persistent Symptoms: A Critically Appraised Topic, Timothy A. Kulpa, et.al., International Journal of Athletic Therapy and Training, Volume 25(1), pp.4-11, (2020). There is moderate and sufficient SORT Level B evidence to support the inclusion of subsymptom threshold (SST) exercise in the multimodal treatment plan for patients suffering from persistent symptoms after concussion. All five included studies reported moderate to very large effects ranging from d = 0.72 to d = 10.64 in reducing symptoms after the implementation of SST aerobic exercise. Additionally, two studies also identified moderate and very large effects (d = 0.77, d = 2.56) favoring aerobic exercise over stretching interventions. These results indicate that this treatment has potential clinical utility and is a viable option to reduce symptoms in patients with postconcussion syndrome and persistent symptoms following concussion.
• Effectiveness of return to activity and return to school protocols for children postconcussion: a systematic review, DeMatteo C, Bednar ED, Randall S, et al, BMJ Open Sport and Exercise Medicine, Volume 6(1), (2020). The current data support the recommendation that children in the acute stage postconcussion should undergo 1–2 days physical and cognitive rest as they initiate graduated RTA/RTS protocols. Prolonged rest may increase reported symptoms and time to recovery. Further interventional studies are needed to evaluate the effectiveness of RTA/RTS protocols in youth with concussion.
• Early Controlled Exercise and Timing of Treatment Following Concussion: A Critically Appraised Topic, Nicholas Hattrup, Hannah Gray, Mark Krumholtz and Tamara C. Valovich McLeod, Journal of Sport Rehabilitation, Volume 29(3), pp.360-366, (2020). There is grade B evidence to demonstrate early controlled aerobic exercise, either alone or in combination with a multimodal treatment plan, may reduce the duration of symptoms following recovery and appears to cause little to no adverse events.
• Does Early Low-Intensity Aerobic Exercise Hasten Recovery in Adolescents With Sport-Related Concussion? Ryan D. Henke, Savana M. Kettner, Stephanie M. Jensen, Journal of Sport Rehabilitation, Volume 29(2), pp.248-252, (2020). The results of this review suggest subsymptom exacerbation LIAEX administered within 10 days following SRC in adolescents does not appear to delay recovery and may result in greater symptom reduction and faster medical clearance than rest. Clinicians who consider applying the LIAEX protocols, as described in the clinical bottom line, should emphasize to their patients that any exercise or activity should be below the threshold of symptom exacerbation. Information in this critically appraised topic should be reviewed in 3 years or after the publication of high-quality RCTs on this topic to determine if the recommendations suggested earlier should be modified.
• Rehabilitation Utilizing Controlled Aerobic Activity in Patients With a Concussion: A Critically Appraised Topic, Janelle Prince, Eric Schussler and Ryan McCann, Journal of Sport Rehabilitation, Volume 29(1), pp.122-126, (2020). Based on the Centre for Evidence-Based Medicine level of evidence criteria, there is grade A evidence to support the safety of controlled aerobic exercise in rehabilitation of an SRC. The included studies are randomized controlled trials that utilized consistent, good-quality patient-rated evidence to drive their results.
• Physical Therapy Evaluation and Treatment After Concussion/Mild Traumatic Brain Injury, Catherine C. Quatman-Yates, Airelle Hunter-Giordano, Kathy K. Shimamura, et.al., Journal of Orthopaedic and Sports Physical Therapy, Volume 50(4), pp.CPG1-CPG73, (April 2020). Clinical Practice Guidelines Linked to the International Classification of Functioning, Disability and Health From the Academy of Orthopaedic Physical Therapy of the American Physical Therapy Association. The primary purpose of this CPG is to provide a set of evidence-based recommendations for physical therapist management of the wide spectrum of patients who have experienced a concussive event.
• Concussion Recovery Timeline of High School Athletes Using A Stepwise Return-to-Play Protocol: Age and Sex Effects, Kaori Tamura, Troy Furutani, Ross Oshiro, Yukiya Oba, Ayaka Ling, and Nathan Murata, Journal of Athletic Training, Volume 55(1), pp.6-10, (January 2020). Implementation of a stepwise return-to-play (RTP) protocol has become the standard management strategy for high school athletes to ensure a safe RTP after concussion. The detailed characteristics of the recovery timeline throughout the steps of an RTP protocol have not been delineated among the adolescent population. Our study provides an estimated stepwise concussion recovery timeline for adolescent student-athletes. Clearance to start step 3 was the benchmark for the recovery timeline, as the duration of the exercise portion of the protocol was consistent across the age and sex groups.
• The use of an intensive physical exertion test as a final return to play measure in concussed athletes: a prospective cohort, Cameron M. Marshall, et.al., The Physician and Sportsmedicine, Volume 47(2), (2019). A total of 759 athletes performed the GGT/mGGT in the study period. Although all asymptomatic, 14.6% of concussed athletes failed the GGT/mGGT while attempting to achieve RTP clearance. Statistically significant relationships were found between failure of the test and symptom severity score on initial presentation and self-reported history of pre-morbid anxiety. When taken together, sex, age, and pre-morbid anxiety significantly predicted the length of time between injury and RTP clearance.
• Mapping brain recovery after concussion: From acute injury to 1 year after medical clearance, Nathan W. Churchill, et.al., Neurology, Volume 93(21), (November 2019). This study provides the first longitudinal evaluation of concussion focused on time of RTP and 1 year after medical clearance, using multiple different MRI measures to assess brain structure and function. These findings significantly enhance our understanding of the natural course of brain recovery after a concussion.
• The Effects of Early Physical Activity Compared to Early Physical Rest on Concussion Symptoms, Landon Lempke, Abbis Jaffri and Nicholas Erdman, Journal of Sport Rehabilitation, Volume 28(1), pp.99-105, (2019). Using the 2011 Oxford Centre for Evidence-Based Medicine taxonomy, level 3 evidence supports the recommendation that early physical activity during the acute phase of a concussion is associated with decreased symptom severity and duration. A lack of high-quality studies and inconsistent interventions limits this recommendation.
• Management of concussion in soccer, Vanessa Hubertus, Niklas Marklund and Peter Vajkoczy, Acta Neurochirurgica, Volume 161, pp.425–433, (2019). Reviews the relevance of sport-related concussion for soccer as well as its diagnosis and management. Finally, we provide insight into future directions for research in this field.
• Factors Affecting Recovery Trajectories in Pediatric Female Concussion, Desai, Natasha, et.al., Clinical Journal of Sport Medicine, Volume 29(5), pp.361-367, (September 2019). Pediatric females, on average, presented later to specialty care for evaluation after SRC than males. Females also took longer to recover on 5 markers of recovery: time to return to school without accommodations, time to return to noncontact exercise, time to return to full sport, time to recovery of neurocognitive function on computerized testing, and time to clinical recovery of vision and vestibular deficits on examination including smooth pursuits, saccades, gaze stability, near point of convergence, and balance. These sex-based differences in recovery disappeared when controlling for time to presentation to specialty care.
• Comparison of Rest to Aerobic Exercise and Placebo-like Treatment of Acute Sport-Related Concussion in Male and Female Adolescents, Barry S. Willer, Mohammad N. Haider, Itai Bezherano, et.al., Archives of Physical Medicine and Rehabilitation, Volume 100(12), pp.2267-2275, (August 2019). 151 adolescent athletes (aged 13-18 years) presenting within 10 days of SRC (mean, 5 days after injury) received a recommendation for rest (rest group [RG]). Their outcomes were compared with matched samples of adolescents assigned to aerobic exercise (exercise group [EG]) or placebo-like stretching (placebo group [PG]). The RG recovered in 16 days, which was significantly delayed compared with EG (13d). The PG recovered in 17 days. Four percent of the EG, 14% of the PG, and 13% of the RG had delayed recovery. There was no difference in recovery time or delayed recovery between male participants and female participants across groups. Female participants prescribed rest experienced an increase in symptoms vs the other groups.
• A Physiologically Based Approach to Prescribing Exercise Following a Sport-Related Concussion, Phillip R. Worts, Scott O. Burkhart and Jeong-Su Kim, Sports Medicine, Volume 49, pp.683-706, (February 2019). A growing body of evidence indicates that initiating exercise earlier in the recovery process following a concussion may reduce symptom burden and lower the incidence of post-concussion syndrome. Preliminary findings appear promising, but data on the appropriate exercise prescription for patients who recently sustained a concussion are limited. We reviewed the literature in healthy individuals and patients with concussion and post-concussion syndrome to develop a physiologically based exercise prescription for the days following a concussion. Using this, practitioners may shorten the rest period and initiate controlled exercise earlier during the recovery process following a concussion.
• Management of concussion in soccer, Vanessa Hubertus, Niklas Marklund and Peter Vajkoczy, Acta Neurochirurgica, Volume 161, pp.425–433, (January 2019). Review the relevance of sport-related concussion for Soccer as well as its diagnosis and management. Finally, we provide insight into future directions for research in this field.
• What factors must be considered in ‘return to school’ following concussion and what strategies or accommodations should be followed? A systematic review, Purcell LK, Davis GA, Gioia GA., British Journal of Sports Medicine, Volume 53(4), (2019). Schools should have a concussion policy and offer individualised academic accommodations to students recovering from sport-related concussion (SRC) on return to school (RTS); a medical letter should be provided to facilitate provision/receipt of academic accommodations; students should have early, regular medical follow-up following SRC to help with RTS and monitor recovery; students may require temporary absence from school after SRC; clinicians should assess risk factors/modifiers that may prolong recovery and require more intensive academic accommodations.
• Concussion, microvascular injury, and early tauopathy in young athletes after impact head injury and an impact concussion mouse model, Chad A Tagge Andrew M Fisher Olga V Minaeva, et.al., Brain, (18 January 2018). Based on post-mortem examination of 4 teenagers and further experiments with both mice and computer modelling, the researchers examined the development and potential mechanisms of CTE. The authors argue that collectively, their results raise concern that repetitive neurotrauma, independent of concussion, may induce early CTE brain pathologies, even in teenagers and young adults. Cumulative exposure to such injuries may also increase risk for other tau protein neurodegenerative diseases, including Alzheimer’s disease (Stein et al., 2015b). These considerations are important not only for understanding and differentiating concussion, TBI, and CTE, but also to inform clinical practice, return-to-play protocols, and public health policy.
• A prospective investigation of changes in the sensorimotor system following sports concussion. An exploratory study, Julie A. Hides, Melinda M.Franettovich Smith, M. Dilani Mendis, et.al., Musculoskeletal Science and Practice, Volume 29, (June 2017). During the playing season, 14 post-concussion assessments were performed within 3–5 days of injury. Significantly decreased sway velocity and increased size/contraction of trunk muscles, were identified. Whilst not significant overall, large inter-individual variation of test results for cervical proprioception and the vestibular system was observed. Preliminary findings post-concussion suggest an altered balance strategy and trunk muscle control with splinting/over-holding requiring consideration as part of the development of appropriate physiotherapy management strategies.
• Convergence insufficiency identifies athletes at risk of prolonged recovery from sport-related concussion, DuPrey K, Webner D, Lyons A, Kucuk C, Ellis J and Cronholm P, The American Journal of Sports Medicine, (16 May 2017).
• Diagnostic terminology, athlete status, and history of concussion affect return to play expectations and anticipated symptoms following mild traumatic brain injury. Kelly, Kiersten; Erdal, Kristi. Journal of Clinical and Experimental Neuropsychology, Volume 39(6), (August 2017), pp.587-595.
• Predictors of clinical recovery from concussion: a systematic review, Iverson GL, Gardner AJ, Terry DP, et al., British Journal of Sports Medicine, Volume 51(12), 2017. A systematic review of factors that might be associated with, or influence, clinical recovery from sport-related concussion. Clinical recovery was defined functionally as a return to normal activities, including school and sports, following injury. The most consistent predictor of slower recovery from concussion is the severity of a person’s acute and subacute symptoms. The development of subacute problems with headaches or depression is likely a risk factor for persistent symptoms lasting greater than a month. Those with a preinjury history of mental health problems appear to be at greater risk for having persistent symptoms. Those with attention deficit hyperactivity disorder (ADHD) or learning disabilities do not appear to be at substantially greater risk. There is some evidence that the teenage years, particularly high school, might be the most vulnerable time period for having persistent symptoms—with greater risk for girls than boys.
• Sport-Related Concussion and Mental Health Outcomes in Elite Athletes: A Systematic Review, Simon M. Rice, Alexandra G. Parker, Simon Rosenbaum, Alan Bailey, Daveena Mawren, and Rosemary Purcell, Sports Medicine , (20 November 2017). Consistent with current recommendations to assess mood disturbance in post-concussive examinations, current evidence suggests a link between sports-related concussion and depression symptoms in elite athletes. Causation cannot be determined at this stage of enquiry because of the lack of well-designed, prospective studies. More research is required that considers a range of mental health outcomes in diverse samples of elite athletes/sports.
• A pilot study of active rehabilitation for adolescents who are slow to recover from sport-related concussion. Gagnon, I.; Grilli, L.; Friedman, D.; Iverson, G. L., Scandinavian Journal of Medicine and Science in Sports, Volume 26(3), (March 2016), p.299.
• Cognitive and physical symptoms of concussive injury in children: a detailed longitudinal recovery study. Crowe, Louise; Collie, Alex; Hearps, Stephen; Dooley, Julian; Clausen, Helen; Maddocks, David; McCrory, Paul; Davis, Gavin; Anderson, Vicki, British Journal of Sports Medicine, Vol. 50(5), (March 2016), p311
• Association between early participation in physical activity following acute concussion and persistent postconcussive symptoms in children and adolescents, Grool A, Aglipay M, Momoli F, et.al., JAMA, Volume 316, Issue 23 (2016).
• Clinical management of sport-related concussion: Developing a roadmap to a successful outcome, Guskiewicz K and Teel E, Kinesiology Review, Volume 4, Issue 2 (2015). In order to promote the most successful outcomes following concussion, a multifaceted team of individuals is required for appropriate injury diagnosis and management. This review explores the primary roles of sports medicine personnel in the diagnosis, management and recovery from sports concussion.
• Cognitive and physical symptoms of concussive injury in children: a detailed longitudinal recovery study, Crowe L, Collie A, Hearps S, Dooley J, Clausen H, Maddocks D, McCrory P, Davis G and Anderson V, British Journal of Sports Medicine , Volume 50, Issue 5 (2016).
• Mild Traumatic Brain Injury and Post-concussion Syndrome: Treatment and Related Sequela for Persistent Symptomatic Disease. Bramley, Harry; Hong, Justin; Zacko, Christopher; Royer, Christopher; Silvis, Matthew, Sports Medicine and Arthroscopy Review, Volume 24(3), (September 2016), pp.123-129.
• Movement disorders and motor impairments following repeated head trauma: A systematic review of the literature 1990–2015. Ozolins, Bede; Aimers, Nicole; Parrington, Lucy; Pearce, Alan J. Brain Injury, Volume 30(8), (April 2016), pp.937-947.
• On-field management and return-to-play in sports-related concussion in children: Are children managed appropriately? Haran, Harini P.; Bressan, Silvia; Oakley, Ed; Davis, Gavin A.; Anderson, Vicki; Babl, Franz E., Journal of Science and Medicine in Sport, Volume 19(3), (March 2016), pp.194-199.
• The persistent influence of concussion on attention, executive control and neuroelectric function in preadolescent children, Moore D, Pindus D, Raine L, Drollette E, Scudder M, Ellemberg D and Hillman C, International Journal of Psychophysiology, Volume 99, p85-95 (2016).
• Removal From Play After Concussion and Recovery Time, R.J. Elbin, Alicia Sufrinko, Philip Schatz, Jon French, Luke Henry, Scott Burkhart, Michael W. Collins, Anthony P. Kontos, Pediatrics , (August 2016).
• The Role of Nutritional Supplements in Sports Concussion Treatment. Ashbaugh, Andrew; McGrew, Christopher, Current Sports Medicine Reports, Volume 15(1), (January/February 2016), p.16
• Cognitive-motor integration deficits in young adult athletes following concussion, Brown J, Dalecki M, Hughes C, Macpherson A and Sergio L, BMC Sports Science, Medicine and Rehabilitation, Volume 7 (2015).
• The diagnostic utility of clinical tests for differentiating between cervicogenic and other causes of dizziness after a sports-related concussion: An international Delphi study, Reneker J, Moughiman M and Cook C, Journal of Science and Medicine in Sport, Volume 18, Number 4 (2015). Dizziness after a sports-related concussion is very common and is associated with prolonged recovery. This study was conducted to identify proper clinically administered tests and measures that are useful in differentiating between cervicogenic and other causes of dizziness after a sports-related concussion. A group of 25 experts in the field of concussion and dizziness, representing several medical disciplines, assessed ten clinical tests. Seven of these tests achieved no consensus among the experts. The clinical tests identified as having strong clinical utility are tests used to identify dizziness originating from the vestibular or central nervous system. No clinical tests specific for the cervical region achieved consensus. Expert opinion from different medical professions and even within professions was widely divergent regarding the utility of clinical tests to assess cervical dysfunction.
• Recognizing the symptoms of mental illness following concussions in the sports community: A need for improvement, Topolovec-Vranic J, Zhang S, Wong H, Lam E, Jing R, Russell K and Cusimano M, Plos One, (4 November 2015).
• Sleep disturbance and neurocognitive function during the recovery from a sport-related concussion in adolescents (abstract), Kostyun R, Milewski M and Hafeez I, American Journal of Sports Medicine, Volume 43, Number 3 (2015).
• A systematic review of the biomarker S100B: Implications for sport-related concussion management, Schulte S, Podlog L, Hamson-Utley J, Strathmann F and Struder H, Journal of Athletic Training, Volume 49, Number 6 (2014). Elevated levels of the astroglial protein S100B have been shown to predict sport-related concussion. However, S100B levels within an athlete can vary depending on the type of physical activity and the methodologic approach used to measure them. This systematic literature review provides an overview of the current literature examining S100B measurement in the context of physical activity. The overall goal is to improve the use of the biomarker S100B in the management of sport-related concussion.
• Assessing Postural Stability in the Concussed Athlete: What to Do, What to Expect, and When, Ruhe A, Fejer R, Gänsslen A and Klein W, Sports Health: A Multidisciplinary Approach, (25 June 2014).
• Assessment, management and knowledge of sport-related concussion: Systematic review, King D, Brughelli M, Hume P and Gissane C, Sports Medicine, Volume 44, Issue 4 (2014). Concussion is often hard to recognise and diagnose. Initial sideline assessment via the Sports Concussion Assessment Tool 3 (SCAT3), Child-SCAT3 or King-Devick test should be undertaken to identify athletes with concussion as part of a continuum of assessment modalities and athlete management strategies. Sports medicine practitioners should be cognisant of the definition, extent and nature of concussion, and should work with coaches, athletes and trainers to identify and manage concussions. The most common reason for variations in management of concussion is lack of awareness of, and confusion about, the many available published guidelines for concussion. Future research should focus on better systems and tools for recognition, assessment and management of concussion. Sport participants’ knowledge of concussion should be evaluated more rigorously, with interventions for sports where there is little knowledge of recognition, assessment, and appropriate management of concussion.
• Cervicovestibular rehabilitation in sport-related concussion: a randomised controlled trial, Schneider K, Meeuwisse W, Nettel-Aguirre A, Barlow K, Boyd L, Kang J and Emery C, British Journal of Sports Medicine, (22 May 2014).
• The evaluation and management of acute concussion differs in young children, Davis G and Purcell L, British Journal of Sports Medicine, Volume 48, Issue 2 (2014), published online (23 April 2013). The aim of this study is to review the current literature on concussion assessment at the sideline and during recovery stages, especially in the age group 5–15 years, and the management of concussion in children and adolescents. The study found that no single paediatric concussion assessment tool has been validated for use from sideline through to all stages of recovery. A young child is physically, cognitively and emotionally very different from an adult, and requires the use of a different set of tools for the diagnosis, recovery-assessment and management of concussion. Age-specific, validated diagnostic tools are required, and management of concussion in children should focus attention on return to learn before considering return to play.
• Objective Functional Assessment After a Head Injury Using Movement and Activity in Physical Space Scores: A Case Report, Farnsworth J 2nd, McElhiney D, David S, Sinha G and Ragan B, Journal of Athletic Training, (19 May 2014).
• Systematic review of prognosis and return to play after sport concussion: Results of the International Collaboration on Mild Traumatic Brain Injury Prognosis, Cancelliere C, et.al., Archives of Physical Medicine and Rehabilitation , Volume 95, Issue 3 (2014). Randomised controlled trials and cohort and case-control studies were selected according to predefined criteria. Reviewed studies had a minimum of 30 concussion cases. Evidence was synthesised qualitatively and studies were categorised as exploratory or confirmatory based on the strength of their design and evidence. This review concluded that there is insufficient confirmatory evidence on the effect of return-to-play guidelines and well-designed studies are urgently needed to understand the consequences of sport concussion across different athletic populations and sports.
• Translating guidelines for the diagnosis and management of sports-related concussion into practice, Donaldson A, Newton J, McCrory P, White P, Davis G, Makdissi M and Finch C, American Journal of Lifestyle Medicine , published online (19 June 2014).
• Sport-related concussion: Evaluation and management, Laura K Purcell, Paediatrics and Child Health, Volume 19(3), pp.153-158, (March 2014). Everyone involved in child and youth sports must recognize the signs and symptoms of concussion, and ensure that any child or adolescent suspected of sustaining a concussion is properly evaluated and managed by qualified medical personnel. The present statement replaces a previous Canadian Paediatric Society position statement published in 2006 and revised in 2012.
• Young age as a modifying factor in sports concussion management: What is the evidence? Foley C, Gregory A and Solomon G, Current Sports Medicine Reports, Volume 13, Issue 6 (2014).
• Exercise intolerance in individuals with postconcussion syndrome, Kozlowski K, Graham J, Leddy J, Devinney-Boymel L and Willer B, Journal of Athletic Training, Volume 48, Number 5, pp.627-635, (2013).

• HeadSmart. Provides an end-to-end sports concussion solution for grassroots schools and clubs and recreational athletes.

• Concussion in Sport Guidelines – An AIS and AMA Initiative, Dr David Hughes, AIS Chief Medical Officer, Smart Talk Seminar Series, Australian Institute of Sport, Canberra (31 May 2016) only
• Sports-related concussion in children and adolescents, Brain Injury Australia Workshop, NSWIS Building, Sydney Olympic Park (13 November 2015)
• Concussion management in community sport - Feature Presentation, Dr Ron Muratore, Chief Medical Officer, National Rugby League, NSW Office for Sport and Recreation, Sports Talks series, (8 October 2014)
• Concussion management in community sport - Club case study, Dennis Lowe, Sports Trainer and Club Official, Penrith Junior Rugby League, Sports Talks (8 October 2014)
• Concussion management in community sport - research, John Searl, Senior Development Manager Regional NSW, ARU, Sports Talks (8 October 2014)
• Traumatic Brain Injury in Athletes: New Concepts, New Dilemmas, James C Puffer MD, Smart Talk Seminar Series, Australian Institute of Sport, Canberra, (16 July 2014)

• Concussion in Sport Australia, Sport Australia, YouTube, (8 October 2018). Every weekend thousands of Australians are concussed while playing sport. Find out how it occurs, how to identify the symptoms and how to treat it. To learn more, visit concussioninsport.gov.au.
• Concussion in Sport Australia: Medical Practitioners, Sport Australia, YouTube, (14 November 2018). Diagnosing concussion can be difficult, even for experienced medical practitioners. Leading sports medicine experts have collaborated to provide contemporary, evidence-based guidelines for the management of concussion in sport.
• Concussion in Sport – Athletes, Australian Institute of Sport, YouTube (20 July 2015). Jayden Warner from the Australian Steelers (National Wheelchair Rugby Team) and Jasmine Simmons (Basketball Australia, Centre of Excellence athlete) share their story on how they managed their concussion. Dr David Hughes (AIS Chief Medical Officer) also provides an important message for all athletes who are suffering with concussion.
• Concussion management and return to learn, Doc Mike Evans, YouTube, (27 August 2017).
• Concussion Videos, Centers for Disease Control and Prevention, US Department of Health and Human Services. Watch pro athletes tell their stories, experts give their insights, and teens and parents discuss concussion.
• Concussions: Don't Hide It, Report It, Take Time to Recover, NCAA, YouTube, (29 July 2011)
• Concussions in Sports – Mayo Clinic. Mayo Clinic, YouTube, (27 September 2012). A young female athlete shares her story along with David Dodick, M.D., neurologist and concussion expert at Mayo Clinic in Arizona, about the road to recovery after a sports concussion.

• Comprehensive Neuropsychiatric and Cognitive Characterization of Former Professional Football Players: Implications for Neurorehabilitation, Alex R. Terpstra, et.al., Frontiers in Neurology, (7 August 2019). Compared to control participants, former professional football players scored significantly higher on the PAI Depression, Mania, and Aggression scales, and significantly lower on response inhibition. (2) Relative to controls, former players with >3 concussions (x ;= 6.1), but not former players with ≤ 3 concussions (x = 2.0), showed (i) significantly higher scores on the PAI Depression scale, (ii) significantly more MINI clinical diagnoses overall, and manic/hypomanic episodes specifically, and (iii) significantly poorer executive function. (3) Mediation analysis revealed that concussion exposure had a significant indirect effect on PAI Depression, Mania, and Aggression via inconsistency of responding on the go/no-go task.
• Long-Term Cognitive Performance of Retired Athletes with Sport-Related Concussion: A Systematic Review and Meta-Analysis, Yanjie Zhang, et.al., Brain Sciences, Volume 9(8), (August 2019). A total of 11 studies that included 792 participants (534 retired athletes with SRC) were identified. The results indicated that the retired athletes with SRCs, compared to the non-concussion group, had significant cognitive deficits in verbal memory, delayed recall, and attention. Additionally, meta-regression demonstrated that the period of time between testing and the last concussion is significantly associated with reduced verbal memory, and increasing age is significantly associated with the verbal memory, immediate recall, and delay recall.
• Influence of playing rugby on long-term brain health following retirement: a systematic review and narrative synthesis, Joice Cunningham, Steven Broglio, Fiona Wilson, BMJ Open Sport and Exercise Medicine, (2018). This review systematically identified and studied six cross-sectional studies of living retired male or female rugby players in which at least one cognitive test was used as an outcome measure were included. Overall findings are mixed. Methodological biases reduce the overall study quality and limited the conclusions that can be drawn. Current evidence suggests that large gaps remain in the understanding of the cause-and-effect relationships between playing rugby and long-term brain health in retired players.
• A Comparison of Cognitive Function in Former Rugby Union Players Compared with Former Non-Contact-Sport Players and the Impact of Concussion History. Hume, Patria; Theadom, Alice; Lewis, Gwyn; et.al., Sports Medicine, Vol. 47(6), pp.1209, (June 2017).
• A systematic review of potential long-term effects of sport-related concussion, Manley G, Gardner AJ, Schneider KJ, et al., British Journal of Sports Medicine, Volume 51(12), 2017. Multiple concussions appear to be a risk factor for cognitive impairment and mental health problems in some individuals. More research is needed to better understand the prevalence of chronic traumatic encephalopathy and other neurological conditions and diseases, and the extent to which they are related to concussions and/or repetitive neurotrauma sustained in sports.
• Age of first exposure to American football and long-term neuropsychiatric and cognitive outcomes. M L Alosco, A B Kasimis, J M Stamm, et.al., Translational Psychiatry, Volume 7, (19 September 2017). This research examined the association between age of first exposure (AFE) to football and behavior, mood, and cognition in a large cohort of former amateur and professional football players. The sample included 214 former football players without other contact sport history. Results indicate that there was no interaction between AFE and highest level of play. Younger AFE to football, before age 12 in particular, was associated with increased odds for impairment in self-reported neuropsychiatric and executive function in 214 former American football players. Longitudinal studies will inform youth football policy and safety decisions.
• Clinicopathological Evaluation of Chronic Traumatic Encephalopathy in Players of American Football. Mez J, Daneshvar DH, Kiernan PT, Abdolmohammadi B, Alvarez VE, Huber BR, et.al., JAMA, 318(4), (July 2017), pp.360–370. In a convenience sample of 202 deceased players of American football from a brain donation program, CTE was neuropathologically diagnosed in 177 players across all levels of play (87%), including 110 of 111 former National Football League players (99%).
• Sport-Related Concussion and Mental Health Outcomes in Elite Athletes: A Systematic Review, Simon M. Rice, Alexandra G. Parker, Simon Rosenbaum, Alan Bailey, Daveena Mawren, and Rosemary Purcell, Sports Medicine , (20 November 2017). Consistent with current recommendations to assess mood disturbance in post-concussive examinations, current evidence suggests a link between sports-related concussion and depression symptoms in elite athletes. Causation cannot be determined at this stage of enquiry because of the lack of well-designed, prospective studies. More research is required that considers a range of mental health outcomes in diverse samples of elite athletes/sports.
• Chronic Traumatic Encephalopathy (CTE) and Former National Football League Player Suicides. Abreu, Marcos A.; Cromartie, Fred J.; Spradley, Brandon D., Sport Journal, (29 January 2016).
• Evidence for acute electrophysiological and cognitive changes following routine soccer heading, Di Virgilio T, Hunter A, Wilson L, Stewart W, Goodall S, Howatson G, Donaldson D and Ietswaart M, EBioMedicine, (18 October 2016).
• Mild Traumatic Brain Injury and Post-concussion Syndrome: Treatment and Related Sequela for Persistent Symptomatic Disease. Bramley, Harry; Hong, Justin; Zacko, Christopher; Royer, Christopher; Silvis, Matthew, Sports Medicine and Arthroscopy Review, Volume 24(3), pp.123-129, (September 2016).
• Movement disorders and motor impairments following repeated head trauma: A systematic review of the literature 1990–2015. Ozolins, Bede; Aimers, Nicole; Parrington, Lucy; Pearce, Alan J. Brain Injury, Volume 30(8), pp.937-947, (April 2016).
• The persistent influence of concussion on attention, executive control and neuroelectric function in preadolescent children, Moore D, Pindus D, Raine L, Drollette E, Scudder M, Ellemberg D and Hillman C, International Journal of Psychophysiology, Volume 99, pp.85-95, (2016).
• Subconcussive Blows to the Head: A Formative Review of Short-term Clinical Outcomes. Belanger, Heather G.; Vanderploeg, Rodney D.; McAllister, Thomas, Journal of Head Trauma Rehabilitation, Volume 31(3), pp.159-166, (May/June 2016).
• Chronic traumatic encephalopathy pathology in a neurodegenerative disorders brain bank, Bieniek K, Ross O, Cormier K, et.al., Acta Neuropathol, (30 October 2015).
• Cognitive-motor integration deficits in young adult athletes following concussion, Brown J, Dalecki M, Hughes C, Macpherson A and Sergio L, BMC Sports Science, Medicine and Rehabilitation, Volume 7, (2015).
• Recognizing the symptoms of mental illness following concussions in the sports community: A need for improvement, Topolovec-Vranic J, Zhang S, Wong H, Lam E, Jing R, Russell K and Cusimano M, Plos One, (4 November 2015).
• Repeated head trauma is associated with smaller thalamic volumes and slower processing speed: the Professional Fighters’ Brain Health Study, Bernick C, et.al., British Journal of Sports Medicine, (29 January 2015).
• Chronic traumatic encephalopathy in sport: a systematic review, Gardner A, Iverson G and McCrory P, British Journal of Sports Medicine, Volume 48, Issue 2 (2014), (26 June 2013). The data from 158 published case studies were reviewed. Critical differences between the older descriptions of CTE (the ‘classic’ syndrome) and the recent descriptions (the ‘modern’ syndrome) exist and suggest that modern CTE is a different syndrome. The new syndrome needs a different nomenclature and further research is required to clearly define the clinical phenotype of the modern CTE syndrome and establish the underlying aetiology. Future research needs to address these issues through large-scale, prospective clinicopathological studies.
• Counseling athletes on the risk of chronic traumatic encephalopathy, Concannon L, Kaufman M and Herring S, Sports Health, A Multidisciplinary Approach, (17 April 2014). Chronic traumatic encephalopathy (CTE) is a rare progressive neurologic disorder that can manifest as a combination of cognitive, mood and behavioural, and neurologic symptoms. Despite clinically apparent symptoms, there is no imaging or other diagnostic test that can confirm diagnosis in living subjects. Diagnosis can only be confirmed postmortem by specific histopathologic features within the brain tissue identified on autopsy. This paper provides a clinical review of literature published between 1990 and 2013 about CTE. When counseling athletes and families about the potential association of recurrent concussions and the development of CTE, discussion of proper management of concussion is important. Unfortunately, to date, there is no equipment that can prevent concussions; however, rule changes and legislation may decrease the risk. It is imperative that return to play is medically supervised by a provider trained in the management of concussion and begins only once symptoms have resolved. In addition, athletes with permanent symptoms should be retired from contact sports.
• Imaging blood-brain barrier dysfunction in football players, Weissberg I, et.al., JAMA Neurology (formerly Archives of Neurology), Volume 71, Number 11, pp.1453-1455, (2014).
• Is There Chronic Brain Damage in Retired NFL Players? Neuroradiology, Neuropsychology, and Neurology Examinations of 45 Retired Players, Casson I, Viano D, Haacke E, Kou Z and LeStrange D, Sports Health: A Multidisciplinary Approach, (25 June 2014).
• What is the evidence for chronic concussion-related changes in retired athletes: behavioural, pathological and clinical outcomes? Paul McCrory, Willem H Meeuwisse, Jeffrey S Kutcher, Barry D Jordan, Andrew Gardner, British Journal of Sports Medicine, Volume 47(5), (2013). The purpose of this paper was to review the current state of evidence for chronic traumatic encephalopathy (CTE) in retired athletes and to consider the potential differential diagnoses that require consideration when retired athletes present with cognitive and psychiatric problems.

• Traumatic Brain Injury in Athletes: New Concepts, New Dilemmas, James C Puffer MD, Smart Talk Seminar Series, Australian Institute of Sport, Canberra, (16 July 2014)

• Scottish Rugby Concussion Study, Scottish Rugby, YouTube, (27 February 2014).

• Australian Sports Brain Bank. Established in 2018, as collaboration between the University of Sydney and Royal Prince Alfred (RPA) Hospital, the aim of the Sports Brain Bank is to define the spectrum of brain changes found in sportspeople who have had one or more episodes of concussion (mild traumatic brain injury or mTBI), by examination of brain tissue removed at autopsy. More information about the project, and about how to donate or support the organisation is available on the website.
• VA-BU-CLF Brain Bank. The largest tissue repository in the world focused on traumatic brain injury (TBI) and CTE. The brain bank contains more than 425 brains, including over 270 brains that have been diagnosed with CTE using the recently defined NINDS criteria for the diagnosis of CTE. Dr. McKee and her team of neuropathologists and other investigators have published a large number of studies focused on CTE which are listed on the website along with further information about the purpose of the research.

• An Investigation of Factors Associated With Head Impact Exposure in Professional Male and Female Australian Football Players, Jonathan Reyes, Biswadev Mitra, Andrew McIntosh, et.al., American Journal of Sports Medicine , (7 April 2020). Playing situations in which players have limited control of the football are a common cause of impacts. Male players sustained a greater exposure to HAEs compared with female players. Female players, however, sustained higher exposure to HAEs than male players during certain skill executions, possibly reflecting differences in skill development. These findings can therefore inform match and skill development in the emerging professional women’s competition of Australian football.
• Sex-Based Differences in the Incidence of Sports-Related Concussion: Systematic Review and Meta-analysis, Jennifer Cheng, Brittany Ammerman, Kristen Santiago, et.al., Sports Health: A multidisciplinary approach , Volume 11(6), (2019). Thirty-eight studies met the eligibility criteria and were included in the meta-analysis. Soccer and basketball demonstrated significantly higher incidence of concussions in females compared with males. Sex-based differences in concussion incidence rates for baseball/softball, ice hockey, lacrosse, swimming/diving, and track and field were not statistically significant. In the meta-regression analysis, there were no significant effects on the rate ratio when evaluating study design, setting, and population.
• Factors Affecting Recovery Trajectories in Pediatric Female Concussion, Desai, Natasha, et.al., Clinical Journal of Sport Medicine, Volume 29(5), pp.361-367, (September 2019). Pediatric females, on average, presented later to specialty care for evaluation after SRC than males. Females also took longer to recover on 5 markers of recovery: time to return to school without accommodations, time to return to noncontact exercise, time to return to full sport, time to recovery of neurocognitive function on computerized testing, and time to clinical recovery of vision and vestibular deficits on examination including smooth pursuits, saccades, gaze stability, near point of convergence, and balance. These sex-based differences in recovery disappeared when controlling for time to presentation to specialty care.
• Comparison of Rest to Aerobic Exercise and Placebo-like Treatment of Acute Sport-Related Concussion in Male and Female Adolescents, Barry S. Willer, Mohammad N. Haider, Itai Bezherano, et.al., Archives of Physical Medicine and Rehabilitation, Volume 100(12), pp.2267-2275, (August 2019). 151 adolescent athletes (aged 13-18 years) presenting within 10 days of SRC (mean, 5 days after injury) received a recommendation for rest (rest group [RG]). Their outcomes were compared with matched samples of adolescents assigned to aerobic exercise (exercise group [EG]) or placebo-like stretching (placebo group [PG]). The RG recovered in 16 days, which was significantly delayed compared with EG (13d). The PG recovered in 17 days. Four percent of the EG, 14% of the PG, and 13% of the RG had delayed recovery. There was no difference in recovery time or delayed recovery between male participants and female participants across groups. Female participants prescribed rest experienced an increase in symptoms vs the other groups.
• Predictors of clinical recovery from concussion: a systematic review, Iverson GL, Gardner AJ, Terry DP, et al., British Journal of Sports Medicine, Volume 51(12), 2017. A systematic review of factors that might be associated with, or influence, clinical recovery from sport-related concussion. Clinical recovery was defined functionally as a return to normal activities, including school and sports, following injury. The most consistent predictor of slower recovery from concussion is the severity of a person’s acute and subacute symptoms. The development of subacute problems with headaches or depression is likely a risk factor for persistent symptoms lasting greater than a month. Those with a preinjury history of mental health problems appear to be at greater risk for having persistent symptoms. Those with attention deficit hyperactivity disorder (ADHD) or learning disabilities do not appear to be at substantially greater risk. There is some evidence that the teenage years, particularly high school, might be the most vulnerable time period for having persistent symptoms—with greater risk for girls than boys.
• Sex Differences in Time to Return-to-Play Progression After Sport-Related Concussion. Stone, Sarah; Lee, Bobby; Garrison, J. Craig; Blueitt, Damond; Creed, Kalyssa, Sports Health: A Multidisciplinary Approach, Volume 9(1), p.41, (January/February 2017).
• Sport Concussion and the Female Athlete, Resch, Jacob E. et al., Clinics in Sports Medicine, Volume 36(4), pp.717 - 739, (October 2017). The purpose of the current review was to summarize the ever-growing body of literature surrounding SC and the female athlete. The current literature supports sex differences on preinjury and postinjury neurocognitive test performance, symptom reporting, and susceptibility to and potential risk for protracted recoveries from SC. Taking this evidence into account, the authors support the need for an individualized approach to SC management based on premorbid functioning, individual risk factors, and clinical presentation after injury, regardless of biological sex.
• Comparing severe injuries by sex and sport in collegiate-level athletes: A descriptive epidemiological study, Hurtubise J, Beech C and Macpherson A, International Journal of Athletic Therapy and Training, Volume 20, Number 4 (2015).
• Differences in symptom reporting between males and females at baseline and after a sports-related concussion: A systematic review and meta-analysis, Brown D, Elass J, Miller A, Reed L and Reneker J, Sports Medicine, Volume 45, (14 May 2015). It is generally regarded that females have more symptomatic presentation than males at all time-points on the concussion spectrum. This review assessed whether differences exist by gender at baseline (pre-season) or post-concussion for self-reported symptoms. Twenty-one studies met the inclusion criteria for analysis. At baseline, females were significantly more likely to report symptoms; such as headache, emotional disturbances, vision or sleep problems. Post-concussion, only one symptom demonstrated significant difference by gender; females were less likely to report confusion than males.