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Assuming the Worst

By June 20, 2011 July 16th, 2015 5 Comments

Remarkably, the streets of Paris are not littered with brain-injured Vélib users...

Yesterday, Queensland’s Courier Mail / Sunday Mail published an article on a recent report, produced by CARRS-Q & commissioned by the Queensland Government, on helmet use and the mandatory helmet law in Queensland:

“QUEENSLAND’S tough bicycle helmet laws are here to stay after a report found any relaxation could increase head injury rates by 50 per cent.

The Sunday Mail can reveal the State Government secretly commissioned a $34,000 study into potentially scrapping compulsory helmet laws ahead of the roll-out of Brisbane’s controversial CityCycle scheme and the release of a report questioning the effectiveness of helmets in preventing injury.”

Incidentally, it was the hard work of one of Brisbane’s most proactive Bicycle User Groups (BUG) that actually forced its release, not the paper’s.

While we have previously written about the CARRS-Q report here, it is worth addressing some of the points raised in the Sunday Mail article.

The CARRS-Q claim that “any relaxation (in the helmet law) could increase head injury rates by 50 per cent” is highly speculative, relying on incomplete data and a number of sketchy assumptions. The authors concede as much in section 7.3 which discusses the imagined effects of a number of possible changes to the helmet law (page 92):

“In this section, an attempt is made to estimate the potential effects of segmented legislation based on available data (which is often patchy) and a range of assumptions.”

In truth, the claim that head injury rates could increase by 50% relies almost entirely on two critical and highly controversial assumptions:

  • Helmet use reduces injuries in the event of a crash by 70%
  • Any change in legislation “would lead to zero use of helmets among the non-mandatory group”.

The first assumption regarding the effectiveness of helmets in preventing injury is still a topic of heated contention amongst academics. The quoted figure comes from here, however numerous other studies and reviews have found significantly lower rates of injury reduction, including one recent study which concluded that “no overall effect of bicycle helmets could be found when injuries to head, face or neck are considered as a whole”.

The second assumption is clearly ridiculous. Even before the introduction of mandatory helmet laws in Australia the helmet wearing rate was estimated to be somewhere between 15% and 30%. It is completely implausible that after two decades of fear-based promotion of helmet use, a change in the law would result in helmet use immediately falling to anywhere near zero.

But not only are the figures produced by CARRS-Q little more than wild speculation, their entire criteria for evaluating any change in policy is flawed, given that it is solely based on whether or not the aggregate amount of injuries will increase. If this were a valid method of evaluation, then any policy which sought to increase the number of people riding bikes would have to be opposed because more people on bikes inevitably leads to more injuries in aggregate (even though the risk to each cyclist is reduced as more and more people ride).

A more reasonable way to evaluate any possible exemptions or amendments to the mandatory helmet law would have been to consider the absolute level of risk to the individual and society of allowing people to ride without helmets in certain situations and to weigh this risk up against the benefits of doing so. This would have lead the authors to some perhaps uncomfortable conclusions had they done so, because as they reluctantly conceded in a previous section:

“the combined evidence presented in these studies [from countries without universal helmet legislation] indicates that the health benefits of bicycling far exceed the health risks from traffic injuries”

Viewed in this light, an exemption from the helmet law for Brisbane’s bike share scheme, CityCycle, would seem perfectly reasonable, considering that compulsory helmets are the most likely reason for CityCycle’s extremely poor usage figures.

CARRS-Q did not even consider the possibility of this sort of exemption, which is surprising given that “concerns about how public bicycle hire schemes will function in the context of compulsory helmet wearing laws” was one of the primary motivations for the report. Had they done so they might have found that the rate of injury amongst users of public bike schemes is extremely low.  In London the public bike share scheme which has been in operation since July 2010 has recorded over 4.5 million trips without a single fatality or serious accident. That’s equivalent to about 50 years worth of CityCycle trips at current usage.

The question is, should we care? The answer is that we should. We should care a great deal. The failure of a bike share scheme like this is bad for all cyclists, whether you would use them or not, and there is only one thing you can do about it: write a letter. Feel free to add this page or anything else from this site to back up your arguments. Tell your friends. Spread the word on Twitter (@freecyclists) and FaceBook.

If we all do nothing, then that’s what we can expect of Government to offer us in return.

5 Comments

  • Anonymous says:

    Your assertion that “more people on bikes inevitably leads to more injuries in aggregate” is actually incorrect. As the number of cyclists on city streets increases, the total number of accidents involving cyclists actually decreases, as evidenced by numerous cities: http://www.bikeleague.org/blog/2011/02/ridership-up-crashes-down-safety-in-numbers-in-minneapolis/ Meaning, of course, that the study in question is even more bunk.

    • paulmartin says:

      It doesn’t have to be incorrect but I see what you’re saying and yes, there is a good chance that actual numbers of injuries would drop. However when you have a cycling modal share (of all trips) in the order of 1.5% it would be difficult to see how a 10-fold increase wouldn’t lead to an increase in the number of cyclists injuries. Of course the rate of injuries per cyclist would be much, much lower… which was the point.

      Hypothetical Example: if 1% of cyclists were injured per year when the cycling mode share is 1.5% (n=10,000 say) = 1.5 cyclists injured
      If the mode share jumped to 15% but injury rates were halved to 0.5% (n=10,000) = 7.5 cyclists injured

      …but it is the injury RATE that is important and what policy should be aiming to improve, rather than the actual number which on a population level is rather unhelpful.

      You are right though, the CARRS-Q study is bunk – but the Government spent $35,000 of taxpayers money on it so they want to get their money’s worth. We’re trying to ensure they don’t.

    • Anonymous says:

      It doesn’t have to be incorrect but I see what you’re saying and yes, there is a good chance that actual numbers of injuries would drop. However when you have a cycling modal share (of all trips) in the order of 1.5% it would be difficult to see how a 10-fold increase wouldn’t lead to an increase in the number of cyclists injuries. Of course the rate of injuries per cyclist would be much, much lower… which was the point.Hypothetical Example: if 1% of cyclists were injured per year when the cycling mode share is 1.5% (n=10,000 say) = 1.5 cyclists injured
      If the mode share jumped to 15% but injury rates were halved to 0.5% (n=10,000) = 7.5 cyclists injured…but it is the injury RATE that is important and what policy should be aiming to improve, rather than the actual number which on a population level is rather unhelpful.You are right though, the CARRS-Q study is bunk – but the Government spent $35,000 of taxpayers money on it so they want to get their money’s worth. We’re trying to ensure they don’t.

  • Anonymous says:

    Paul, I’m late with my ‘comment’, but as always with you all the way – great post!

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