Originally Posted by
John C. Ratliff
You will note that PPE (personal protective equipment, such as a bicycling helmet), is at the bottom of these controls. It is the least effective of the hierarchy of controls.
“risk compensation” does occur in adults, and probably in kids too.
Yes, bicyclists can and do ride without helmets, but in the case of a fall,
numerous studies (see the link for one recent one) have shown the efficacy of bicycle helmets in preventing substantial head injures that can be fatal.
PS--I was able to add files from my trip to Hong Kong.
1. Helmets are at the bottom of the list of controls. They are also at the very bottom of the LAB's "Rules of the Road" regarding safe riding. Yet to listen to some, they are a major part of safe cycling, which is just not true, as you have here pointed out.
2. The fact that risk compensation does occur supports my assertion. Although the study you cite is far from comprehensive. It is interesting that those who usually do not wear helmets do not ride less safe with them, but it also seems to indicate that those who wear helmets on a regular basis are riding less safe because of them.
3. Here's a significant excerpt from the abstract you linked to:
Originally Posted by McNally & Whitehead
Bicycle helmets were found to be effective in reducing the severity of head injuries sustained in common accidents. They reduced the risk of an AIS>3 injury, in cases with head impacts, by an average of 40%. In accidents that would cause up to moderate (AIS=2) injuries to a non-helmeted rider, helmets eliminated the risk of injury. Helmets were also found to be effective in preventing fatal head injuries in some instances. The effectiveness of helmets was demonstrated over the entire range of cycle speeds studied, up to and including 14 m s(-1). There was no evidence that helmet wearing increased the risk of neck injury, indeed helmets were found to be protective of neck injuries in many cases. Similarly, helmets were found to offer an increase in protection even when an increase in cycle speed due to risk compensation was taken into consideration
All kinds of pro-helmet stuff in here, which is great, but I'll pick it apart on a couple of points:
- The AIS>3 / 40% line. That's great, but the AIS scale goes up to 9. I'm sure helmets help with injury on the lesser end of the scale, but I wonder how effective they are at the higher injury levels, which occur due to forces far in excess of what helmets are designed for. That the authors chose to word it as they do might indicate bias.
- "Helmets were also found to be effective in preventing fatal head injuries in some instances." is qualitatively different than your statement "...efficacy of bicycle helmets in preventing substantial head injures that can be fatal."
While I draw different conclusions than you do, I'm interested to hear what the bare-headers have to say about the study, because there's some pretty conclusively damning results in there which support helmet use.
4. I've been to Hong Kong. I didn't see any cycling infrastructure at all in the part of the city where we stayed and I walked around quite a bit, saw many different parts of the city via subway. I would not consider HK a safe cycling mecca, and very few riders wear helmets.
Bottom line is you've still only addressed one of the three issues I raised when claiming helmets make riding less safe, and in fact found support for one of them...