Originally Posted by
mconlonx
Risk compensation and bicycle helmets.
Phillips RO1, Fyhri A, Sagberg F.
Routine helmet users reported higher experienced risk and cycled slower when they did not wear their helmet in the experiment than when they did wear their helmet, although there was no corresponding change in HRV. For cyclists not accustomed to helmets, there were no changes in speed, perceived risk, or any other measures when cycling with versus without a helmet. The findings are consistent with the notion that those who use helmets routinely perceive reduced risk when wearing a helmet, and compensate by cycling faster. They thus give some support to those urging caution in the use of helmet laws.
I don't see where there is riskier behavior (as opposed to "perceived risk"), unless it was the helmet wearers cycling slower when they didn't wear one.
I've noticed it personally, that when I'm accustomed to wearing a helmet and ride without one, it feels riskier for at least a few minutes, so I don't doubt their results.