Failure to wear a bicycle helmet is dumb, even for adults. Research has shown that bicycle accidents account for more traumatic brain injuries each year than football injuries. The American Association of Neurological Surgeons found that bicycle accidents played a role in about 86,000 of the 447,000 sports related head injuries treated in emergency rooms in 2009. Football accounted for 47,000, baseball 38,394. Cycling was also the leading cause of sports related head injuries in children under the age of 14 causing 40,272 about twice as many as football.
In 90% of fatal bicycle accidents in the United States in 2009, the bicyclists were not wearing helmets.