(Undated) -- 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 and were donated to the study by the players family.
Three of the 14 who played only high school football had CTE, while 48 of 53 college players had it.
The study's senior author, Dr. Ann McKee, says "this is by far the largest [study] of individuals who developed CTE that has ever been described. And it only includes individuals who are exposed to head trauma by participation in football."
McKee is Chief of Neuropathology at VA Boston Healthcare System and director of the CTE Center at the BU School of Medicine.
The study focused on the connection between football and the neurodegenerative disease.
McKee, says "We're seeing this [CTE] in a very large number that participated in football for many years. So while we don't know the exact risk and we don't know the exact number, we know this is a problem in football."