The BMJ has an article on the effects of Canadian bike helmet legislation. Between 1994-2003, Canadian provinces with mandatory bike helmet laws saw a 54% reduction in bike-related head injuries as compared to only 33.1% in provinces without helmet laws.
So helmet laws work, right? Well, not exactly…
As the article notes, injury rates were already on a downward trend. And there are confounding factors (such as new bike facilities, fewer cyclists, enforcement, etc) that may also explain the reduction.
After taking baseline trends into consideration, however, we were unable to detect an independent effect of legislation on the rate of hospital admissions for cycling related head injuries.
Conclusions: Reductions in the rates of admissions to hospital for cycling related head injuries were greater in provinces with helmet legislation, but injury rates were already decreasing before the implementation of legislation and the rate of decline was not appreciably altered on introduction of legislation. While helmets reduce the risk of head injuries and we encourage their use, in the Canadian context of existing safety campaigns, improvements to the cycling infrastructure, and the passive uptake of helmets, the incremental contribution of provincial helmet legislation to reduce hospital admissions for head injuries seems to have been minimal.
Here are the time-series graphs. The vertical dotted line shows when the helmet law went into effect. As you can see, injury rates were declining anyway, with the law having no effect.
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I’m not sure I follow this. You’re more likely to have a head injury without a helmet but less likely to be as seriously injured with a helmet on your head when involved in a ‘incident'(fall or collision). However, there is no proven safety if you wrap your head in the mandatory helmet legislation.
Do I have it right?
@tom: You got it, mate! Helmet laws are useless, and even helmets have limited effect. A woolen cap or a bear fur hat are almost as good…
[…] is ineffective by looking at places that implemented such laws, including California and parts of Canada. Oh, and […]