On 8/5/2011 5:02 PM, Frank Krygowski wrote:
Many years ago, the eminent British researcher Mayer Hillman pegged the
benefit-to-risk ratio for cycling at 20:1 in favor of cycling. His
estimate was based on calculations of years of life gained vs. years of
life lost for society as a whole. That included, for example,
pedestrians not killed by a car because the driver chose to cycle
instead of drive.

Last year de Hartog et.al. pegged the ratio at 9:1 in favor of cycling
in the Netherlands, and 7:1 in Britain, this time for just the cyclists
themselves. This did not account for things like fewer bystander deaths
due to air pollution, for example.

The latest paper gives even more optimistic estimates. A study of the
urban cyclist use of Barcelona's bike sharing system pegged that ratio
at 77 to 1 in favor of bicycling, for those replacing car trips with
bike trips.

A brief radio interview discussing this is at
http://www.cycling-embassy.org.uk/au...-too-dangerous


Warning: There is some slight mention of helmets - specifically, the
statement that none of the people in the study wore them; and that they
discourage riding.

This is consistent with data from London's and Dublin's and Paris's bike
share plans, with millions of users but no (or almost no) serious
injuries. (And OTOH there's Melbourne's, which requires helmets and thus
gets almost no use.)

The paper's free to download at
http://www.bmj.com/content/341/bmj.c5293.full.pdf

Really, how safe does cycling have to be, and by how much do its
benefits have to exceed the tiny risk, before we say "Stop worrying.
It's safe enough"?


Frank makes the mistake of thinking people value facts and proper
statistical analyses over gut feelings and conventional "wisdom".

--
Tºm Shermªn - 42.435731°N, 83.985007°W
I am a vehicular cyclist.