By ERIC JAFFE, The Atlantic Cities
Typically in transportation — and most social arenas, for that matter — laws promoting safety precautions lead to an increase in public health. Legislation on speed limits, drunk driving, and seatbelt are a few of the most obvious examples. Even bans on the relatively new phenomenon of driver-texting seem to be doing the trick, according to early evidence.
With bike helmet laws, however, the connection isn’t quite so clear.
Take a recent study published earlier this month in BMJ [PDF]. The Canadian research team, led by Jessica Dennis of the University of Toronto, analyzed the rate of cycling-related hospital admissions for head injuries across the country between 1994 and 2008 — an enormous research sample of more than 66,000 people. The size and length of the study allowed Dennis and collaborators to track the injuries against the emergence of bike helmet laws in various provinces.
What they found initially seemed to suggest that this legislation improved public safety. In provinces with helmet laws, the rate of head injuries among young people decreased 54 percent and the rate among adults decreased 26 percent. At the same time, in provinces without the laws, the rate among youth riders dropped only 33 percent and among adults remained constant. (It bears mention that the study was the first to examine the effects of helmet laws on adults.)
But upon closer inspection, according to Dennis and company, this positive effect failed to stand. On the contrary, the researchers concluded that head injuries were decreasing across the country at a rate that wasn’t "appreciably altered" by the new helmet laws. Other rider health initiatives — namely, public safety campaigns and the introduction of better bike infrastructure — rendered the contribution of helmet laws "minimal":
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https://www.theatlanticcities.com/commute/2013/05/do-bike-helmet-laws-really-make-people-safer/5732/
Biking in Baltimore