Thursday 28 June 2012

Helmets: a Dutchman goes to Canada

Hans Voerknecht has been to a Velo-City conference in Vancover to explain why mandatory helmet laws are not such a great idea.  One of his statistics is that In the Netherlands, where cycling is ubiquitous, 13.3 per cent of the cyclists admitted to hospitals with injuries wore helmets — even though just 0.5 per cent cent of Dutch cyclists wear helmets.  Maybe tourists from Anglo Saxon nations wearing helmets are disproportionately represented in the hospital statistics.  Maybe also those with helmets are perceived by motorists or perceive themselves to be less vulnerable.  The debate will go on.
Meanwhile I am reminded that earlier this year a Metropolitan Police Officer stated to me, during the course of the same conversation in which he explained that his officers were under a high workload so it was difficult to deal with law breaking motorists,  that he would like to see helmet compulsion here.  He did not seem to think there would be any problem with the Metropolitan Police finding the resources to enforce any such law and I bet he would be right.  Where there is a will, there is a way.


21 comments:

  1. 13.3 per cent of the cyclists admitted to hospitals with injuries wore helmets — even though just 0.5 per cent cent of Dutch cyclists wear helmets

    Did he give a citation for these figures? If they are correct, cyclists wearing helmets are being injured at 30 times the rate of non-helmet wearers. No wonder they wear helmets!

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    1. Gareth >>No wonder they wear helmets!>>
      Your conclusion makes no sense.
      You're apparently suggesting that the 13.3% self-selected themselves as dangerous and thus wore helmets, and that if more helmets were worn that there would have been fewer admissions. Certainly some would have already made the decision to do something that involved a higher-than-average risk, but statistically very unlikely to account for a 30-fold increase in risk.

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  2. Some thoughts at https://plus.google.com/u/1/108088562149420085956/posts/WFSFYvPjZrW

    (apologies for the link, trying to include that audience too)

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  3. If the Met can find the manpower to enforce a (hypothetical) helmet law, how come they can't even find the manpower to enforce ASL?

    ASL cameras would easily be self financing....

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  4. http://en.m.wikipedia.org/wiki/Government_spending#section_3

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  5. I meant to say that I suspect that the helmet wearers are mainly racers, so they have more accidents.

    (PS my previous post was a copy/paste error - please feel free to delete if you can.)

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    1. I also rudely forgot to link to the site that drew me to this, and suggested the explanation.

      http://waronthemotorist.wordpress.com/2012/06/28/who-are-all-these-self-harming-dutch-helmet-wearers/

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  6. Indeed. As Luke points out, the explanation lies in the character and behaviour of those Dutch cyclists who happen to wear helmets. They are people who are cycling for sport, which is more risky than simply cycling to the shops or to school, an activity which practically no Dutch person will wear a helmet for.

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  7. Let face reality if Metropolitan Police found the resources to deal with law breaking motorists then there wouldn't be a need for helmets. Cycling isn't a particularly dangerous activity, despite the macho fantasies of the Lycra crowd.

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  8. Gareth, it's highly unlikely that those wearing helmets are 30 times more likely (or 26.6 times to be pedantic) to have accidents than those who don't wear helmets, for the simple fact that they proportionately do far greater mileage than those who don't wear helmets. Moreover, bear in mind that the 99.5% who don't wear helmets will include some very,very occasional cyclists who probably clock up very few kilometres on an annual basis.

    In fact, as I have commented elsewhere, on a mile per mile basis, there is probably very little difference in probability of being injured.If one assumes that the average racing cyclist clocks up 3-500ks per week that's probably 20-30 times the mileage of the average of the rest of the population.

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    1. "as I have commented elsewhere, on a mile per mile basis, there is probably very little difference in probability of being injured.If one assumes that the average racing cyclist clocks up 3-500ks per week that's probably 20-30 times the mileage of the average of the rest of the population."

      Unfortunately you've just plucked that '20-30 times' figure out of thin air. Not only have you grossly underestimated the amount of 'ordinary' cycling clocked up by Dutch cyclists - to and from school, to and from the shops, to and from work, several times a day - you have also failed to realise that those 'average racing cyclists' will themselves be ordinary helmet-less cyclists when not engaging in recreational cycling. Of those hundreds of kms you mention, a considerable proportion, if not the majority, will be cycled without a helmet.

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    2. Sir Velo, can you explain where you get your "pedantic" figure of 26.6 from? If three significant figures were justified (which they are not) then I make it 30.5.

      I'm also not sure why you think normalizing by distance travelled is the appropriate measure here. (Even if we had the figures for the two populations, which we don't.) Risk is surely roughly proportional to exposure.

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  9. aseasyasridingabike: are you seriously trying to tell me that the guys/girls who wear helmets for,presumably, training and racing purposes are not doing far greater distances than the little old lady who potters down to the shops and back once a week? Or that they don't do greater distances training than commuting,for example? I ride a bike in the UK, and wear a helmet when out training/racing and go helmet less for commuting etc. I can honestly say that I do at least 30 times the mileage with the helmet and full gear on than otherwise.

    If you prefer, look at it another way: 87% of hospital admissions are for those not wearing a helmet.That's hardly a glowing endorsement of their not being worn either is it?

    To reiterate, when you allow for the weighting of distance travelled, you will probably find that there is little difference on a km per km basis between the accident rates requiring hospital admission of helmet and non-helmet wearers

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    1. "I ride a bike in the UK, and wear a helmet when out training/racing and go helmet less for commuting etc. I can honestly say that I do at least 30 times the mileage with the helmet and full gear on than otherwise."

      I do many more miles without a helmet than with one. I don't suppose my anecdote counts for any more than yours.

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    2. My use of a bicycle is almost exclusively for utility purposes, and I accumulate 50 miles per week. You can do that with one 7(.15) mile round-trip per day, 7 days a week, or 2 20 mile round-trips plus some dinking around town the rest of the week. From what I read of Dutch bicycle use my utility mileage would not be unusual there.

      Professional-class racers may accumulate 10x that mileage per week, but that's far less than 0.5% of the population, and they don't ride 1000 miles per week. Exposure to risk surely matters, but it's also clear that behavior matters too.

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  10. Rule 129

    Double white lines where the line nearest you is solid. This means you MUST NOT cross or straddle it unless it is safe and you need to enter adjoining premises or a side road. You may cross the line if necessary, provided the road is clear, to pass a stationary vehicle, or overtake a pedal cycle, horse or road maintenance vehicle, if they are travelling at 10 mph (16 km/h) or less.
    When I commute by bike 100% of motorist fail to comply with this rule. When drive 100% of motorist get really upset when I comply with this rule.

    So when the police the police can enforce existing road laws, and when motorist stop killing 10 people a day, only then can new ones be introduced.

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  11. Sir Velo (and others) are assuming that the 0.5% wearing helmets were counted by some kind of poll or questionnaire directed at individual cyclists.

    I think it's much more likely that this figure emerges from simply counting cyclists as they pass a number of representative locations. That is a far easier way to do such a survey and automatically takes account of any differences in exposure.

    There is plenty of video of Dutch cycling on the internet so you can easily do your own survey. If you spot a helmet on much more than one in every two hundred cycling heads, then I'm a Dutchman!

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    1. When I lived in Nijmegen in 2006-07 the new police bicycle patrols started out wearing helmets as per regulations, but very soon switched to baseball caps after they realised that the sight of two helmets bobbing above a crowd of rush-hour cyclists says "police patrol" and warns wrongdoers to disappear down a side-street. In Holland the only people who wear the things everyday are American expats, who seem to suffer from a curious belief that a piece of the sky is going to fall on them.

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    2. Anon >>I think it's much more likely that this figure emerges from simply counting cyclists as they pass a number of representative locations. >>
      Short of a different explanation, I think this would be correct, and therefore takes into account the number of miles ridden, and is consistent with those observations on the videos and in-person. The discussion of relative miles traveled becomes moot.

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  12. "he would like to see helmet compulsion here. He did not seem to think there would be any problem with the Metropolitan Police finding the resources to enforce any such law"

    You bet there wouldn't be: nicking cyclists for not wearing helmets - as the Australian police forces have discovered - is a sure-fire way of bumping up your law-enforcement figures and filling your on-the-spot fines kitty without actually doing anything very much. All you have to do is post your overweight policemen at traffic intersections at the morning and evening rush hours, then wait for the victims to appear. Helmetless cyclists are much more visible than (say) motorists texting at the wheel; they're slow enough to catch if they try running off; and they also tend to be nice middle-class people who won't shower you with obscenities or pull a knife on you when accosted. Money for jam...

    On the injured Dutch cyclists point, the most likely explanation that occurs to me is that these are indeed mostly sports cyclists. Road bikes are fast and light and their centre of gravity is well forward, so going over the handlebars is a very real possibility if you stop suddenly. Dutch utility bikes, by contrast, are so heavy and differently balanced that falling off forwards is pretty well impossible: you just fall sideways. I know: I've tried it with my own bike, and no matter how hard I braked on however steep a hill I couldn't even lift the back wheel off the ground.

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  13. Even if we agree that making the wearing of helmets compulsory is probably counterproductive and that they probably don't give as much protection as their advocates suggest. Can we agree that they give some protection and so on balance their wearing should at least be encouraged. Coming off your bike when wearing a helmet is unlikely to make things worse despite what some in the medical profession might think.

    Take a look at this U tube video for a Swedish air bag type helmet and watch how the cycle dummy's head goes back onto the car bonnet. The collision speed is only 20mph but even at this speed serious head injuries would be incurred if no head protection was worn and this type of accident at these speeds is I believe very common at junctions and at red lights etc.

    http://www.youtube.com/watch?feature=player_embedded&v=uVZ0qiA-jBY

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