Comment Not Prove, but Yes IMPLY (Score 5, Insightful) 213
Correlation does not PROVE causation. It can however strongly imply causation, especially as we can plainly see and infer the other mechanisms at play here. Let's not be like the cigarette companies here and turn a blind eye to the likely health dangers with misdirection. As for sample bias, when you are 110 for 111 I don't care what your bias is, the likelihood is that far over half of serious football players suffer brain damage of some sort or severity. Football and boxing are not likely to go away in our generation, but they will have to be modified greatly or they will eventually be considered a sport only us ignorant ancients would engage in.