Keeping a lid on it?

I like my head the way it is. So I like to wear my bicycle helmet – it makes my head feel safe. But I did a quick google and the statistics say the helmet does Jack. Mandatory helmet laws might even be dangerous. WTF?!

broken helmet

This is relevant at the moment, because the public bike scheme starting up in Melbourne is wondering how they’re going to get the punters into helmets. If helmets are provided, they will probably be ill-fitting, sweaty and literally lousy. Mmm mmm.

Could we change the laws, so all the the V-Liners from Traralgon and the sun-burned pommy tourists wobble off without a helmet? Could we do that?

I googled some more, and soon got buried under an avalanche of claim and counter claim. Helmets are complicated. I tunneled to the surface with the following facts tucked in my pockets.

1. If your head is going to hit something, you better hope its got a helmet on it. Obviously.

2. Australia brought in universal mandatory bike helmet laws in the early 1990s.

3. The laws are not associated with a significant decrease in cyclist head injuries in Australia.

Now, if you’re paying attention, you’ll notice that these 3 facts don’t really follow. I found out that there’s complicating factors. Here’s two of them

1. Heads with helmets on are slightly more likely to hit things when they fall off bikes, due to increased size and mass.

2. People overestimate how safe the helmet makes them, and do stuff bare-head cyclists wouldn’t.

I read more on both sides. Most of them are from such luminary institutions as the Bicycle Helmet Safety Institute, or the pedal club of Smalltown, USA. The only piece not accompanied by about 15 pages of personal cycling anecdotes is from the Road Accident Prevention Research Unit of the University of Western Australia.

It argues that compulsory helmets prevented an estimated 20-44 head injuries (of which 84 % were only moderately severe) per year in WA between 1992 and 1998. That’s an 11-21% decrease in bicycle head injuries.

An 11-21 percent decrease! Sweet! We should do it. Right?

Maybe. Some risks aren’t worth defending against. The UWA study estimated costs of the mandatory helmet laws, including promotion and enforcement and the costs of helmet purchase. Under the various assumptions, the estimated net benefit of the scheme is between -$15.1 million and $2 million. They’re saying mandatory helmet laws could be good, but are more likely not worth it.

That’s not definitive. I kept reading. I found a cool article in the British Medical Journal by Dorothy Robinson, a Professor of Statistics. She was not happy about mandatory helmet laws.

She argued the laws dissuade riding. The UWA article mentioned this, but only as a relevant factor they had to exclude from calculations. But Robinson had stats: In Melbourne, counts before and after the introduction of the law found a 42 percent fall in child cyclists, and a 29 percent fall in adult cyclists. In NSW they only counted children, and found a 35 percent fall.

That seems surprisingly high to me.

If people don’t cycle they may substitute a PT or car commute, instead of other exercise. Robinson cites UK research indicating that the years gained due to health attributable to cycling outweigh those lost to head trauma by 20:1.

So should the Victorian Government seize the day, and use the public bike scheme to sneak through a change in the law?

I did a pop survey, and people say they would feel unsafe riding without a helmet. But maybe that’s a good sign – we could end up with high helmet use and freedom of choice. I wouldn’t mind the feeling of the wind in my hair.

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Thomas the Think Engine is the blog of a trained economist. It comes to you from Melbourne Australia.

5 thoughts on “Keeping a lid on it?”

  1. I like Jerry Seinfeld’s view of helmets and the helmet law:

    “There are many things that we can point to as proof that the human being is not smart. The helmet is my personal favourite. The fact that we had to invent the helmet. Now why did we invent the helmet? Well, because we were participating in many activities that were cracking our heads. We looked at the situation. We chose not to avoid these activities, but to just make little plastic hats so that we can continue our head-cracking lifestyles.

    “The only thing dumber than the helmet is the helmet law, the point of which is to protect a brain that is functioning so poorly, it’s not even trying to stop the cracking of the head that it’s in.”


  2. A couple of points:

    – not all issues can or should be reduced to economics, or financial cost/benefit analyses.

    – repeal the helmet law and you’ll probably get the helmet industry and union threatening job losses will eventuate (kind of like the packaging industry currently whinging the alcopop tax will cost their jobs)

    – i can’t give exact details, but i recall a british study in which the researcher attached a proximity sensor or radar to his bike and then rode with and without a helmet. the data showed that without a helmet other traffic gave him a wider berth and riding was made safer. i think he had one accident in which he was sideswiped whilst wearing a helmet.
    so, perhaps it’s not just “People overestimate how safe the helmet makes them, and do stuff bare-head cyclists wouldn’t”, but other road users make judgments about helmet-users that make cyclists less safe. wankers.


  3. I would be afraid to ride in Sydney even with a helmet where all the other road users ride/drive like psychos (in fact, I’m afraid to walk- there were 383 pedestrian DEATHS in Sydney CBD last year!). On the other hand, I ride all the time in Zürich where helmets are not compulsory, the cyclists ride carefully and the car drivers are courteous. Also, we have marked bike lanes on every main road, which cars actually respect. So I think that feeling and being safe on the road has a lot more to do with the road being safe than what you wear on your head.


  4. Hit your head hard enough once and you will forever opt for a helmet. Be involved in an accident with a head injury and you will also look forward to popping on a lid.

    If you don’t then natural selection is a fantastic thing, thick people have thin skulls… Oh well

    also, blood from the head seems more sticky and is a bitch to get out of your hair.

    Byo helmet is going to be the only option for Melbournes rentals, but as most of them will be stolen in the first 2 weeks I doubt there will be too many bikes available.


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