That's what it says in this Times article;

http://www.timesonline.co.uk/tol/com...cle6828120.ece

And it also says:

"...According to their research, cyclists are at significantly more
risk of being hit by cars on roads that include cycle lanes. On
average, an overtaking car will pass 18cm closer to a bike in a cycle
lane than it would to a bike with which it was merely sharing a road.
That is roughly the distance that your pedals stick out from your cog.
Do bear in mind that you also have elbows...

....And yet, throughout our cities, provision for cyclists remains
perfunctory at best, and lunatic at worst..."

--
Car Free Cities
http://www.carfree.com/
Carfree Cities proposes a delightful solution
to the vexing problem of urban automobiles.