Boston University Study Estimates 74.5% of Deceased NFL Players Had CTE
United States
Kirby Lee/Reuters
Source Analysis
What Happened
What Happened
Where Sources Agree
- arrows_inputCTE Prevalence Estimate: Coverage highlights that a new study published in JAMA Network Open estimates 74.5% of the 2,362 former NFL players who died between 2008 and 2023 had CTE, framing the findings as a more precise population-level prevalence estimate after accounting for selection bias.
- arrows_inputAdjusted CTE Prevalence: Outlets concur on the 74.5% CTE prevalence estimate for deceased former NFL players, a figure reached by adjusting for selection bias where families of symptomatic players were five times more likely to donate, according to Boston University researchers.
- arrows_inputNFL Safety Commitment: Some outlets verify that the NFL emphasizes its commitment to player safety by implementing strategies such as the introduction of Guardian Caps and rule changes designed to reduce concussions and head impacts, according to official NFL statements.
Where Sources Disagree
- arrows_outputCTE Prevalence Context: While some sources contextualize the 74.5% NFL CTE prevalence by noting the disease appears in less than 1% of the general population, other outlets report the study's estimate without including this broader population benchmark.
- arrows_outputNFL Safety Measures Debated: The NFL cites its implementation of Guardian Caps and rule changes to reduce head impacts as evidence of its commitment to player safety. In contrast, some independent experts emphasize that these measures are insufficient and argue the league must take further action to protect athletes.
Timeline
October 28, 2026
Caveats, Dementia Findings, Responses: Authors cautioned the estimate applies only to deceased former NFL players and does not predict how many living players have CTE; they also estimated 27.2% had dementia during their lifetime and urged clinical evaluation and further research, while the NFL and NFLPA reiterated safety and support efforts.
October 28, 2026
Bias Adjustment Yields 74.5%: After adjusting for selection bias—researchers estimated families of symptomatic players were about five times more likely to donate—a population-level estimate indicated that 74.5% of the 2,362 deceased former NFL players likely had CTE (about 1,760 people). The analysis applied the adjusted donor rates to the full set of deaths from 2008–2023.
December 31, 2023
High CTE Rate Among Donors: Among the players who donated their brains for research (about 396 donors), 362 were diagnosed with CTE, a donor-level prevalence of roughly 93.5%. The donor sample drove earlier high estimates but may reflect selection bias toward symptomatic cases.
Summary by Ground AI
Sources
See All 148A varied selection of sources chosen by Ground to reflect the diversity of this story’s coverage.
Most Written About
The stories getting the most coverage from the last 24 hours
Source Analysis
Timeline
October 28, 2026
Caveats, Dementia Findings, Responses: Authors cautioned the estimate applies only to deceased former NFL players and does not predict how many living players have CTE; they also estimated 27.2% had dementia during their lifetime and urged clinical evaluation and further research, while the NFL and NFLPA reiterated safety and support efforts.
October 28, 2026
Bias Adjustment Yields 74.5%: After adjusting for selection bias—researchers estimated families of symptomatic players were about five times more likely to donate—a population-level estimate indicated that 74.5% of the 2,362 deceased former NFL players likely had CTE (about 1,760 people). The analysis applied the adjusted donor rates to the full set of deaths from 2008–2023.
December 31, 2023
High CTE Rate Among Donors: Among the players who donated their brains for research (about 396 donors), 362 were diagnosed with CTE, a donor-level prevalence of roughly 93.5%. The donor sample drove earlier high estimates but may reflect selection bias toward symptomatic cases.
