(CNN)Eighty-seven of 91 former NFL players who donated their brains to science after death tested positive for a brain disease that is believed to be linked with repeated head trauma and concussions, researchers said.
The former players were found to have had chronic traumatic encephalopathy, known as CTE, according to the U.S. Department of Veterans Affairs and Boston University.
It's not clear why some players develop the disease and others don't.
The study results don't necessarily mean that 96% of all NFL players are at risk for CTE, said Dr. Robert Cantu. The brains came from players who, while they were alive, had concerns about CTE. His group began its work in 2008.
The data was published on the website for the Concussion Legacy Foundation, which Cantu co-founded, and first reported Friday by the documentary TV program "Frontline."
The former players were found to have had chronic traumatic encephalopathy, known as CTE, according to the U.S. Department of Veterans Affairs and Boston University.
It's not clear why some players develop the disease and others don't.
The study results don't necessarily mean that 96% of all NFL players are at risk for CTE, said Dr. Robert Cantu. The brains came from players who, while they were alive, had concerns about CTE. His group began its work in 2008.
The data was published on the website for the Concussion Legacy Foundation, which Cantu co-founded, and first reported Friday by the documentary TV program "Frontline."
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