[themitigating]

The amount of risk taking obviously has some increase in the number of cyclists that get into accidents. However the outcome of the accident is more important.

So for each accident: how bad was in the injury, cost, permanent damage, and recovery time. Then compare that between both groups.

For example it could be that although wearing a helmet increases the risk of an accident by 15% it decreases the risk of serious brain injury or long term damage by 60%. If that were the case then the helmet is beneficial.