A new study shows 110 of 111 brains examined of former NFL players had chronic traumatic encephalopathy or CTE.
Researchers from Boston University School of Medicine and VA Boston Healthcare found that 177 of the 202 total brains tested showed evidence of CTE.
All specimens belonged to former football players at all levels of the sport.
Three of the 14 who played only high school football had CTE, while 48 of 53 college players had it.
The study focused on the connection between football and the neurodegenerative disease.
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