"What's most disturbing, perhaps, is that these cognitive deficits have a real-world impact: When compared with similar students without a history of concussions, athletes with two or more brain injuries demonstrate statistically significant lower grade-point averages."
All well and good, but what was the grade point average comparison BEFORE the injuries? Is it possible that - I don't know - football doesn't attract the smart, nerdy types?
Once again, we could be in the "correlation is not causation" territory that has plagued modern "studies."
You are onto something I pointed to yesterday. School districts where football is a big time sport will actually hold kids back in kindergarten and grammar school just to give them extra eligibility time in their late teens in highschool. SEE Yesterday’s Debate over what I believe is an attempt to do this statewide in three states: http://www.freerepublic.com/focus/f-news/2846104/posts