Study: 25% of NFL players in sample had CTE

A new study published Tuesday in the British Medical Journal estimates that at least 25% of NFL players who died between 2016 and 2021 had chronic traumatic encephalopathy (CTE). Researchers examined 878 players who appeared in at least one NFL game and died during the six-year span, using brain samples donated between 2008 and 2021. Because CTE can only be diagnosed after death, the study relied on donations and narrowed the sample based on donation timing, demographic data, and death-certificate information. Lead author Dr. Daniel Daneshvar called the 25% figure a “low end,” with a maximum possible prevalence near 97%.