On 9/12/2015 5:00 PM, Phil W Lee wrote:
John B. considered Sat, 12 Sep 2015 08:54:40
+0700 the perfect time to write:


About 75% of all bicyclists who die each year die of head injuries.

I think you'll find (unless it's very different from the UK, which
seems unlikely given the common mechanism of injury) that it's 75%
that have a brain injury at the time of their death, which may well
have occurred anyway due to other injuries.
Not much point in keeping your head in one piece if you've bled out
anyway. And even a motorcycle helmet won't save your head if a heavy
truck drives over it, or even some much lighter vehicles. So the most
you can do is cite that 75% as an upper bound.

I suspect the origin of the overestimate was a propaganda statement that
"75% of bicyclist fatalities involve a head injury." At least, that's
the way I first saw it expressed years ago. (Sorry, no citation.)

That version may be literally true - as in, the dead cyclist may have
had his abdomen run over by a truck's wheels, and he also got a little
scratch on his head. But the phrasing was obviously intended to trick
the reader into believing that helmets might prevent something like 75%
of fatalities. And other helmet proselytizers missed the subtlety and
went for the straight-out lie.

Similarly, after the infamous Thompson & Rivara paper of 1989 claimed
that helmets prevent 85% of head injuries, another paper used that
number to claim universal helmet use would prevent 85% of American bike
fatalities. And astonishingly, that made it through peer review.


--
- Frank Krygowski