MIAMI (CBSMiami) – A new report from the Centers for Disease Control and Prevention could break new ground on concussions suffered by ex-NFL players and the degenerative effects they have on them.

According to U.S. News and World Report, the new CDC study found NFL players are three times as likely to die from neurodegenerative diseases like Alzheimer’s or Parkinson’s as the general population. The study analyzed 3,500 retired NFL players who played for at least five years, according to U.S. News.

Out of those studied, 334 former players have died and neurodegenerative diseases caused or contributed to 27 deaths, U.S. News reported.

Still, the researchers said that multiple studies will be needed to concretely attribute the repeated blows to the head players receive to the increased risk of neurodegenerative disease.

The NFL has sought in recent years to change the rules to try and reduce the concussion risk to players. However, much of the responsibility for diagnosing the concussions relies on the players to report problems to team trainers and doctors.

With players always ready to take a spot on the 53-man roster, many players don’t report their full symptoms to keep playing and thereby increasing their risk of further injury.

The NFL gave a $30 million to the Foundation for the National Institutes of Health for brain injury research this week and has worked with universities who are investigating CTE, or chronic traumatic encephalopathy, which is believed to trigger some neurodegenerative disease.