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Players were 1:1 propensity score matched to general population normative male samples on age, race, and highest education level. Cognitive subtests included digit symbol matching (DSM), gradual onset continuous performance test (Grad CPT), trail making test parts A and B (Trails-A -B), paired associates memory for verbal (Verbal PA), paired associates memory for visual (Visual PA), and vocabulary. The HIE metrics examined were age of first exposure to football (AFE), lifetime exposure to football, professional career duration, and lifetime concussion history. Multivariable linear regressions with dominance analysis examined associations and relative importance of demographic data and HIE metrics on cognitive performance; independent\n                      <jats:italic>t<\/jats:italic>\n                      -tests examined group differences across cognitive subtests using mean differences (MDs) and 95% confidence intervals (95%CIs).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Age, race, and highest education demonstrated complete dominance over all HIE metrics across the seven cognitive subtests among former NFL players. Professional football career duration demonstrated overall general to complete dominance over the majority of HIE metrics across cognitive subtests, such that greater career duration was associated with lower cognitive performance, while AFE was often dominated by other HIE metrics. Compared to the normative sample, former NFL players had significantly lower DSM (MD:\u2009\u2212\u20093.45, 95% CI \u2212\u20095.97, \u2212\u20090.92), Grad CPT (MD:\u2009\u2212\u200914.62, 95% CI \u2212\u200916.61, \u2212\u200912.64), Verbal PA (MD:\u2009\u2212\u20095.04, 95% CI \u2212\u20095.90,\u2009\u2212\u20094.18), Visual PA (MD: \u2212\u20091.18, 95% CI \u2212\u20091.90, \u2212\u20090.46), and vocabulary performance (MD:\u2009\u2212\u20093.84, 95% CI \u2212\u20095.45,\u2009\u2212\u20092.24), while Trails A and B were not statistically different (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009\u2265\u20090.06).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Demographic factors were completely dominant over HIE metrics for cognitive performance. Among only HIE metrics, professional football career duration superseded lifetime concussion history and AFE. Worse cognitive performance was observed among former NFL players compared with a matched normative sample with varying effect sizes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s40279-026-02492-7","type":"journal-article","created":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T21:36:44Z","timestamp":1784237804000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Demographic and Football-Related Characteristics Associated with Objective Cognitive Performance in Former NFL Players with a Normative Sample Comparison: An NFL-LONG Study"],"prefix":"10.1007","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0007-1362","authenticated-orcid":false,"given":"Landon B.","family":"Lempke","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin L.","family":"Brett","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruben J.","family":"Echemendia","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wesley R.","family":"Cole","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. 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Dr. Brett acknowledges support from the National Institute of Neurological Disorders and Stroke (NINDS; award number L30 NS113158-02) and the National Institute on Aging (award number K23AG073528-01) under the National Institutes of Health (NIH). He is a part-time employee of the National Hockey League. Dr. Echemendia is a paid consultant for the National Hockey League (NHL) and a member of the NHL\/NHL Players\u2019 Association (NHLPA) Concussion Subcommittee; a paid consultant for Major League Soccer (MLS) and chair of the MLS Concussion Committee, the US Soccer Federation; and occasionally provides expert testimony in matters related to mild traumatic brain injury and sports concussion. Dr. DeFreese acknowledges support from the Atlantic Coast Conference and the Association for Applied Sport Psychology. Dr. McCrea reports a grant from NFL during the conduct of the study as well as grants from NIH, Centers for Disease Control (CDC), Abbott Laboratories, DoD, and NCAA outside the submitted work. Dr. Mannix acknowledges support from the NINDS (U01NS096835), The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NS115942-01A1), the DoD (W81XWH1920011), and Abbott Pharmaceuticals. Dr. Meehan receives royalties from ABC-Clio publishing for the sale of his books, Kids, Sports, and Concussion: A Guide for Coaches and Parents, and Concussions; Springer International for the book Head and Neck Injuries in Young Athlete; and Wolters Kluwer for working as an author for UpToDate. His research is funded, in part, by a grant from the NFL. All authors declare no other potential conflicts of interest.","order":1,"name":"Ethics","label":"Conflicts of Interest","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The dataset is not available for public sharing or upon individual\u2019s reasonable requests owing to privacy and sharing restrictions from the IRB.","order":2,"name":"Ethics","label":"Availability of Data and Material","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The study was performed in accordance with the standards of ethics outlined in the Declaration of Helsinki. All study procedures were reviewed and approved by the University of North Carolina-Chapel Hill\u2019s IRB (no. 19\u20131065; approved 12\/3\/2019\u2014current), Medical College of Wisconsin IRB ( no. PRO00035132; approved 12\/02\/2019\u2014current), and Boston Children\u2019s Hospital IRB (no. IRB-P00040264; approved 12\/28\/2021\u2014current).","order":3,"name":"Ethics","label":"Ethical Approval","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Informed consent was obtained from all individual participants included in the study. Completion of the questionnaire after the introductory paragraph implied consent.","order":4,"name":"Ethics","label":"Informed Consent","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","order":5,"name":"Ethics","label":"Code Availability","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"All authors agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Specific author contributions are as follows: LBL established research hypotheses, planned analyses of the data, interpretation of study findings, manuscript preparation and revision, final approval of the submitted manuscript. BLB, RJE, WRC, JDD, DLH, RCM, KMG, MAM, and WPM III carried out creation and distribution of the study survey, support of data analysis plan, interpretation of study findings, manuscript preparation and revision, and final approval of the submitted manuscript.","order":6,"name":"Ethics","label":"Author Contributions","group":{"name":"EthicsHeading","label":"Declarations"}}]}}