Modulating Factors Affecting Sports-Related Concussion Exposures: A Systematic Review and Analysis

In the United States, the Centers for Disease Control and Prevention estimates that 1.6-to-3.8 million concussions occur annually in sports. This quantitative meta-analysis of one hundred and twenty-one sports-related concussion studies, across fourteen youth sports, investigated the contributions of statistical constructs, and diagnostic methods, considering the impact of nationwide laws and education, as well as distinguished injury surveillance techniques, in this widely diverse literature. Concussion study research designs were found to have differing diagnostic, statistical, and methodological techniques. Among less frequently studied, non-high-contact, sports, a meta-analysis investigated relative rates of concussion and sex differences. Findings indicated considerable variation in reported concussion incidence rates due to the sport played, but also due to the number of study authors listed and the proportion of female athletes represented. Such factors likely influence the reported incidence of sports-related concussions, especially in sports not typically associated with a high risk of head injuries. To better capture the incidence of sports-related head injuries and concussion, a universal data repository for youth concussions might be established to provide an ongoing, comprehensive, and accurate picture of concussions in youth and collegiate athletics. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: N/A I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data produced in present work are contained in the manuscript