BOSTON — Dave Duerson, a former NFL player who committed suicide in February, had “moderately advanced” brain damage related to blows to the head, according to the researcher who made the diagnosis.

“It’s indisputable” Duerson had chronic traumatic encephalopathy, a disorder linked to repeated brain trauma, Dr. Ann McKee said yesterday.

The findings were announced as part of an effort conducted by the Center for the Study of Traumatic Encephalopathy at Boston University’s School of Medicine, which has the brains of more than 70 athletes and military veterans, with football players comprising more than half of the athletes.

Duerson, a Pro Bowl safety, played in the NFL for 11 seasons. He spent seven years with the Bears and won a Super Bowl with the 1990 Giants.

“Dave Duerson had classic pathology of CTE and no evidence of any other disease,” McKee said, “and he has severe involvement of all the [brain] structures that affect things like judgment, inhibition, impulse control, mood and memory.”

The body of Duerson, who was 50, was found in Sunny Isles Beach, Fla., on Feb. 17. He left a note asking that his brain be given to the NFL’s Brain Bank.