Dr. Shafeeq Ladha, director of the Gregory W. Fulton ALS and Neuromuscular Disease Center at Barrow, weighed in on the discussion of amyotrophic lateral sclerosis (ALS) in football players.

Retired football player Tim Green suspects his repeated head injuries in the sport caused his ALS, a fatal neurodegenerative disease.

Several studies have linked football to ALS, but scientists caution that an association between two things does not necessarily mean that one causes the other. Dr. Ladha told the Syracuse Post-Standard that many studies looking at the link between ALS and football are skewed because they are retrospective, meaning they are based on data that has already been collected.

“The best way to solve this problem is to take a group of NFL players, follow them over 30 years, and see who gets ALS compared to the general population,” he said.

Full story: Tim Green’s ALS: Is it fair to blame football?