Football Study Consistent with Car Accidents

Researchers outfitted college football players helmets with devices to measure the speed, direction and force at which their heads were struck during a game. Surprisingly, the data failed to predict which hit would or did cause a concussion or brain injury. 

This is consistent with the real world, wherein it is difficult to determine who might walk away from a trauma without a brain injury and who might suffer an injury. Factors such as the positioning of the head, the exact line of force, heredity and other unknown variables all must come into play. Some individuals can simply have an increased susceptibility to traumatic brain injury, for reasons we do not fully understand.