Not to be any sort of jerk, but until you've spent enough time cycling in traffic to be comfortable, your intuition regarding the safety of that activity is suspect. Several factors are involved. First of all, there is the risk compensation phenomenon (http://www.ncbi.nlm.nih.gov/pubmed/21418079), which is also seen for seatbelt-wearers etc. and causes users of any "safety" device to behave less safely to compensate for that use. This phenomenon also applies to other road users, so that when they see a cyclist they perceive to be "protected" by a helmet they don't give her as much space, they drive faster, etc. (http://www.sciencedirect.com/science/article/pii/S0001457506...) Other factors are follow-on effects from the fact that requiring helmets reduces cycling rates (http://www.nber.org/papers/w15658): fewer cyclists make for more dangerous roads for everyone (http://www.ctc.org.uk/campaign/safety-in-numbers) and cyclists who cycle less aren't as good at cycling. There is a "rhythm" to riding in traffic, and after I've taken some time off, I have to be more careful until I sharpen up. With regular practice, you know:
- exactly how close the damn delivery truck is going to pass, just by the engine
sound
- which car is going to change lanes without signalling, not from its brakelights
but from its slight pause in acceleration
- how fast you have to pedal to intimidate an entering SUV into waiting for you
to pass instead of turning left completely across all lanes
- the distinct whine of a BMW (the official car of assholes) that's going
to attempt a right hook from 50 feet behind
- etc.The first study you mention is also pretty interesting, however it only is measuring the efficacy of legislation on safety and is not measuring the efficacy of helmet wearing itself. Im not sure if legislation on its own is a good proxy for helmet wearing and the authors do state: "While helmets reduce the risk of head injuries and we encourage their use..."
I used to ride around for years without a helmet despite laws that mandate that I wear one. Interestingly, even after two tickets I still rode around without a helmet because I perceived that I was an awesome cyclist with perfect judgement and not prone to human error at all, a typical attitude for my age at the time.
A few months after starting to wear a helmet because people were being judgmental, not because I thought I would ever need it, I got into an accident where I went flying off my bike. Short story, it saved my brain.
Ya ya, this is anecdotal, but what was important about that experience for me, is it made me realize that my perceptions of safety were totally off. Our own control over the world is actually minimal, and even we fail despite how perfect we think we are at assessing the situation.
I was stupid. Being a cyclist wasnt experience enough for me to assess my safety, I needed a couple of near misses to realize how wrong I was. I needed to physically experience how my head deals with its momentum and pavement. I needed to experience how flying through the air face first with my arms extended to cushion the blow results in my back hitting the pavement followed next by the back of my head. Some people need to learn these things through experience.
If I were to assume everyone was as dense as I was at the time, I would counter with something like "until you've had enough experience being in accidents and thrown into objects, your intuition regarding the safety of that activity is suspect"
I didnt used to listen to people like me either!
Another occasion that really sticks out in my mind is the time I laid the bike down and jumped off to the side to avoid a child who literally jumped out from behind cover into the street directly in my path. If I had been in a car, going the same speed, that episode would have ended very differently.
I don't have a problem with helmets in general. I never snowboard without a helmet. There are many rivers I won't kayak without a helmet. I don't usually wear a helmet when riding horses, but there are exceptions, like polo. I'm sure I'll encounter other circumstances that seem helmet-appropriate as well. The point is, bicycle commuting is not an extreme sport, so enforcing the conventions of extreme sport is an effective way to discourage it.
For every anecdote, there is another anecdote. You only think your helmet saved you, while I know that my lack of helmet did not harm me in the crash I described. (And if we're going to speculate intuitively, it's a good thing I didn't have a solid bulky object on my head to catch on the pavement and impart a jolt of rotational acceleration to my brain!) If you've never considered the phenomenon of risk compensation, you could think more deeply about an issue that is much more complicated than "it's bad to injure your head". Fortunately, there's a place you can go to educate yourself: http://www.cyclehelmets.org/
Risk compensation also applies to drunk drivers, but no one argues that driving drunk is just as risky as driving sober. Yes, it plays a part in the whole equation, but it doesnt necessarily discredit the theory!
Just because other people take bigger risks while cycling with helmets on, doesnt mean that we should write off helmets. They can be very effective when combined safe cycling practices, and perhaps thats how that information can be made useful.
'you could think more deeply about an issue that is much more complicated than "it's bad to injure your head"'
Are you about to argue that head injuries could be considered good? Please enlighten this simple thinker.