Originally Posted by gpburdell

The thing that jumps to mind with this study is they used hospital and morgue records to identify injured cyclists. Effectively they're only collecting data from cyclists injured enough to go to the hospital or the morgue.


What about the cyclists who had a crash, but by virtue of wearing a helmet didn't need to go to either? It's conceivable that many people without a head injury would treat moderate road-rash and bruises at home or at a local urgent care facility (which were becoming more common in the early 90's) but would go to an ER if they did have a head injury.


Can this study really make any valid conclusions about overall effects of helmet use without including a potentially substantial group?