Thursday, September 22, 2016

Helmets--Oh Yeah, We're Going There!

Yeah, I know.  On the list of fun topics to discuss, helmets rank right in between politics and anal warts.  But don't blame me, because the media started it:


(Which is why pro cyclist injuries and deaths declined so steeply after the UCI instituted a helmet rule in 2003.  Oh, wait...)

A major study of bike helmet use around the world from more than 64,000 cyclists has found helmets reduce the risks of a serious head injury by nearly 70%.

The study also found neck injuries are not associated with helmet use and cyclists who wear helmets reduce their chance of a fatal head injury by 65%.

Wow.  Sounds conclusive, right?  Well, not so fast:

The compulsory wearing of bike helmets in Australia has long been a source of frustration for some cyclists, who argue it reduces participation rates. Previous studies have indicated helmet use encourages risk-taking behaviour or does not reduce serious injury to the brain.

But a comprehensive review by Australian statisticians Jake Olivier and Prudence Creighton from the University of New South Wales that drew together data from more than 40 separate studies found helmet use was associated with dramatically reduced odds of head injuries.

What?

New South Wales, Australia!?!

CUE RECORD-SCRATCH SOUND!

In case you forgot, New South Wales is the possibly the most bike-hostile place in the world:


Gay, a member of the junior party in the Liberal-National coalition, is minister for roads for New South Wales, and has described himself as “the biggest bike-lane sceptic in the government”. The NSW government is about to get rid of a much-loved and much-used AU$5m (£2.4m) protected cycleway in Sydney’s city centre – a move Clover Moore, lord mayor of Sydney since 2004, describes as “a shocking breach of trust”.

And recently raised all of its bicycling-related fines into the stratosphere:


And that's not including the fine for not carrying ID while cycling, presumably so they can make sure all those other charges stick and you don't give them a fake name like "Mike Hunt" or "Flavius Scranus" in order to dodge the fine.

So yeah, I'm going to look askance at any research paper that comes from a place where the fine for not wearing a plastic hat is over $300--and doubly so when it's presented at a Finnish safety meeting:

The findings were presented in Finland this week at Safety 2016, the world conference on injury prevention and safety promotion.

Which sounds a lot like a euphemism to me:


Plus, what kind of safety conference has a ferris wheel?


Those things are dangerous!


Okay, well actually the ferris wheel Freds say they're not dangerous.  They probably just seem like they're more dangerous than they are to people who don't know anything about them--you know, like bicycles.  That's why I always wear a helmet when I go to the amusement park.

And while I'm striving for accuracy, I suppose it's not entirely scientific to deride a study just because it comes from a certain antipodean state with an anti-bike bias, or because I find the alliterative juxtaposition of Finnish safety meetings and ferris wheels to be conveniently amusing.  We need to look at the actual study, right?  Well sadly I can't, because it's behind a paywall and I'm not made of money over here (I'm made of high-modulus carbon fiber), so for the purposes of this blog we'll have to settle for the abstract:

Methods: Four electronic databases (MEDLINE, EMBASE, COMPENDEX and SCOPUS) were searched for relevant, peer-reviewed articles in English. Included studies reported medically diagnosed head, face and neck injuries where helmet use was known. Non-approved helmets were excluded where possible. Summary odds ratios (OR) were obtained using multivariate meta-regression models stratified by injury type and severity. Time trends and publication bias were assessed.

Okay, so they looked at a bunch of injured cyclists in various places--or, more accurately, articles and data about injured cyclists that other people have already collected and interpreted.  Now, how is it even possible to draw new conclusions about any of this data if you don't even know the total number of helmeted versus unhelmeted cyclists riding around out there in the general population?  And what were the circumstances that led to these injuries in the first place?  Isn't it possible the head injury odds they're presenting really just amount to statistical noise?

Well, maybe yes and maybe no.  But the danger here isn't the idea that helmets may offer you some additional protection from injury, which frankly sounds pretty reasonable to me, and which is why I wear them sometimes.  The danger is that these sorts of studies lead to conclusions like this:

Conclusions: Bicycle helmet use was associated with reduced odds of head injury, serious head injury, facial injury and fatal head injury. The reduction was greater for serious or fatal head injury. Neck injury was rare and not associated with helmet use. These results support the use of strategies to increase the uptake of bicycle helmets as part of a comprehensive cycling safety plan.

Funny how the conclusion is never  "make conditions safer for cyclists," isn't it?  But wait, actually it is--in an earlier paper about bicycle-related head injury trends in New South Wales, co-written by Jake Olivier, one of the very people behind this most recent study.  Indeed, in this earlier paper (WARNING: PDF) there's a graph showing a decline in head injuries--after increased cycling infrastructure:



The conclusion?  New South Wales needs more infrastructure development:
Not only that, but the paper also warns of the dangers of "meta-analyses" (which is what the most recent study is) and says that such studies can be biased when they relate to legislation:

"Results from mata-analyses should be interpreted with caution since ultimately, they are analyses of statistical studies rather than a large statistical study in itself and sample bias will always be present regardless of who is carrying out the analysis, particularly when it is related to a political agenda or legislation."

Yet this is exactly what this most recent study is--a meta-analysis being used in support of mandatory helmet laws:

The researchers cautioned that helmets were not a “panacea for cycling injury” and did not eliminate head or face injuries or offer protection to other parts of cyclists’ bodies. But it does make the case more difficult for those who oppose mandatory helmet wearing, they said.

“The legislation of mandatory helmets for cyclists is a controversial topic and past research on its effectiveness has been somewhat mixed,” the study said. “Irrespective of past research, the results of this review do not support arguments against helmet legislation from an injury prevention perspective.”

So sorry, but based on the researcher's own caveats in an earlier paper, I ain't buying it--nor do I understand why so many people pretend there aren't cities on Earth where people cycle safely in huge numbers and that helmets have absolutely fuck-all to do with it.

Instead of passing dumb laws and clobbering people with massive fines and presenting the media with dubious studies all we need to do is copy the cities where cycling actually works and that's that.

Speaking of helmets, in yesterday's post I featured the rider who commenter "bad boy of the north" subsequently dubbed "The Narwhal:"


(Thanks again for the photos, Aaron.)

And I was delighted to see that the Narwhal himself left a comment:

Anonymous said...

Hey! That's me - the narwhal.

I have a rearview camera under my seat that Bluetooths to my tablet on the selfie stick.

It works like a rearview mirror and record my rides from behind.

Thanks for making me famous, Bikesknob!

September 21, 2016 at 2:14 PM 

Though after reading it I have to admit I was even more confused.  After all, with any number of video recorders available out there in the marketplace--not to mention good old-fashioned analog rearview mirrors--one wonders why you'd endanger yourself and others by taping a golf club onto your head. 

But hey, he's wearing a helmet, so clearly he's 70% safer than I am!*

*(No offense to the narwhal by the way, I support whatever it is you're doing, and you make the world--or at least the Williamsburg Bridge--a far more entertaining place.)



from Bike Snob NYC http://ift.tt/2dcJw3j

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