I unequivocally think there's a link between playing football and CTE, we've seen it in 90 out of 94 NFL players whose brains we've examined, we've found it in 45 out of 55 college players and six out of 26 high school players. Now I don't think this represents how common this disease is in the living population, but the fact that over five years I've been able to accumulate this number of cases in football players, it cannot be rare. In fact, I think we are going to be surprised at how common it is.