Bicycle helmets and the lawBMJ 2013; 346 doi: https://doi.org/10.1136/bmj.f3817 (Published 12 June 2013) Cite this as: BMJ 2013;346:f3817
All rapid responses
Goldacre and Spiegelhalter offer a good overview of the complexities of the issue of cycle helmet use.
It is indeed a puzzle that something so superficially obvious as the benefit of helmets turns out in practice to be incredibly difficult to detect in any real cyclist population.
Or, as Goldacre's catchphrase has it, "I think you'll find it's a bit more complicated than that".
It is notable that the US National Highway Traffic Safety Administration and Centers for Disease Control have recently dropped the widely-cited figure of 85% reduction in head injuries proposed by Thompson, Rivara and Thompson (1988), a figure which has dominated calls for cycle helmet legislation but which has consistently failed to be borne out either by real cyclist populations or by other, more methodologically rigorous, studies.
On a positive note the London cycle hire scheme has failed to provide the carnage that was predicted by some, and indeed appears to have a remarkably good safety record considering the traffic density and likely inexperience of riders.
My own conclusion, having read far more of the research than I am sure is good for my sanity, is that cycling is not actually particularly hazardous, that simple and well understood techniques may significantly improve its overall safety, and that helmets are probably very good at preventing minor injuries but evidence of any significant effect on serious injuries is hard to find.
And actually this is not really a surprise. They are designed to model a completely unrealistic scenario, to work in a way that has little to do with real cycle crashes or real brain injury, and they are in any case woefully inadequate in any collision involving motor traffic - which of course means the majority of crashes that lead to serious or fatal injury.
It has been my view for some time that the public debate should move away form talking up the risks of cycling in order to promote a fix that does not, in the end, seem to mitigate the very well, and move instead to the promotion of cycling generally, and safe cycling especially.
Moreover, there is a pressing need for driver education too. Most collisions between cyclists and motor vehicles are the motorist's fault. There is a rhetoric against "scofflaw" cyclists jumping red lights and so on, but actually everybody breaks traffic law all the time, it's just that cyclists break different laws. How many drivers never exceed the speed limit or park illegally?
Finally, I think we should seriously reconsider the use of "paint pot engineering". Painting narrow cycle lanes at the side of the road creates a false impression that cyclists not only need very little space, but have no right to use more than that. It sends a pernicious and wrong message to both novice cyclists and drivers.
Competing interests: No competing interests