How Dangerous is Riding a Bike?

July 29, 2011


Helmets credited for drop in cycling head injuries. That seems like an obvious story, right? As Greg Webster, director of primary healthcare information for the Canadian Institute for Health Information says, “it intuitively makes sense.”

But intuitively, it made sense that the sun orbited the Earth, because that’s what you see when you have a limited perspective or are only looking at a certain set of facts. There are two pieces of compelling data in the study:

  • There were 4,325 cycling-related injuries in 2009-10, compared to 4,332 eight years earlier. Meantime, the number of cycling-related head injuries stood at 665 last year, compared to 907 in 2001-2002.
  • Among the most severe cycling injury admissions of the past decade (those requiring admission to a special trauma centre), 78% of those hospitalized with a head injury were not wearing a helmet when their injury occurred

The first point says nothing about how many cyclists actually wear helmets. Are more cyclists wearing helmets? I don’t know, and neither, it seems, does the CIHI. There’s no cause available for the reduction in head injuries, so attributing it to helmet use is mere speculation. It’s quite reasonable speculation, but speculation nonetheless.

The second point is much more convincing, but still not conclusive. 78% of cyclists hospitalized for head injuries weren’t wearing a helmet sounds bad, but again, it doesn’t quite prove anything. How many of those hospitalized would have been protected by a helmet?

That said, it’s certainly good enough for me, and I already thought wearing a helmet is a good idea.

One other interesting, non-helmet item from the study: Only one out of four cycling hospitalizations was caused by a collision with a motor vehicle. That’s an important item for those who dismiss the usefulness of bicycle helmets because they won’t stand up to the impact of a motor vehicle crash.

Lastly, remember this one very important item from the study:

Motor vehicle collisions still represent the number two cause of injury in Canada, second only to falls, with 18,964 hospitalizations in 2009–2010.

No matter what you think about bicycle safety, you’re far more likely to be killed or injured in an automobile.

That’s something to keep in mind as we answer the question posed by the Globe & Mail: How young is too young to bike with your child?

I know nothing about child safety, so I’m not going to attempt to pontificate on the subject. But the article does offer this rather hysterical quote from a Colorado safety organization:

There is no age when a child should go on a bicycle with a parent … Who would want to take a chance of the child falling? Even if you weren’t in danger of being hit by a car, just a slip, the baby goes down and the baby would go down very hard.

Most of the other people in the article are more reasonable, and so perhaps it’s silly to dwell on this one. But many of the comments on the article are as hysterical as you’d expect from online comments, so it’s clearly not a unique opinion. That doesn’t make it any less stupid.

There are risks to riding a bike with your child. But there are risks to anything, and one of the biggest risks – driving – rarely receives any consideration whatsoever.

All that said, though: “Cars aren’t as dangerous as bikes” is not an excuse for cyclists to do whatever they want. Even if bikes don’t cause anywhere near the carnage cars do, there can still be serious consequences for reckless and careless cycling. Licensing cyclists remains a silly idea, but enforcing the rules of the road for cars and bikes is sadly necessary, given the seemingly increasing number of people who think traffic laws are merely recommendations.

All of this is to say: Biking riding a bike poses certain dangers that need to be evaluated with the proper amount of perspective and data. Letting gut instincts or particular ideologies rule your ride doesn’t make anyone any safer. Safety is an ongoing concern that needs to be considered at all times, not something to make up your mind about once and stick to for the rest of your life.

Addendum: I neglected to mention Chris Turner’s excellent piece on risk perception, where he points out that modes of transportation that suffer fewer accidents and fatalities are paradoxically seen to be more dangerous, because the uniqueness of the event means it gets more attention. Thousands of people die in motor vehicle collisons every year, but it gets less attention because it always happens. So a few parents riding bikes with their children in trailers may look dangerous, but no one bothers to think about all the parents driving 120 km/hr on busy highways with small children.

Posted in Cycling and tagged , .

  • http://pem247.com Henry

    How can you bring attention to the fact that automobile accidents are the number two cause of injury, and not suggest that motorists wear helmets. For those collisions when an airbag just does not cut it? Or How about – what you point out as worse – falls. What if we all wore helmets all of the time? Fall injuries may drop significantly, especially for head and brain injuries. I am sure you will find that every doctor and brain scientist agrees that helmets can save a life or two in a minor fall. A helmet does not care if your were sitting on a bicycle saddle, roller skates, or a bar stool. Especially with children learning to walk, those stairs can be quite a dangerous thing for toddlers. Even if it saves one life it would be worth it: right? ;)

  • Ryan

    For one thing, I don’t have much interest in writing about automobile safety.

    I’m fairly ambivalent about helmet laws – I don’t think they’re necessary, but I’m also not offended by them – but I find many cyclists seem to find any sort of cycling laws, or even recommendations, so abhorrent that you’d think no government had ever passed a safety regulation before. Some points are valid, while others merely sound like a 13-year-old complaining that his parents keep telling him to clean up his room.

    I find dogmatic, absolutist arguments on either side of helmets & safety to be foolish & unproductive.

  • http://wiredcola.com Ryan Cousineau

    One thing you’d like to see in the helmet efficacy studies is what kind of injuries they’re supposed to be reducing.

    What’s special about the head is, in short, the brain (and to a considerable extent, the eyes and face, but half-shell bike helmets don’t help those). So if the protection the helmet causes is against road rash on the head, that’s roughly an argument for wearing knee and elbow pads, too.

    If helmets are measurably mitigating against long-term brain injuries or changing head-trauma fatalities into recoverable brain injuries, then we’re talking about progress.

    That said, the meta-risk is that helmets might (or might not) reduce brain injuries on a case-by-case basis, but that they tend to (by some subtle but observable psychological and behavioral effects) reduce the amount of cycling in a region. Because cycling prevalence is a well-established correlate with cycling safety (okay, I’m not sure we know which way the arrow of causation points, but there’s some hints that more cyclists lead to safer cycling, not the other way around), a helmet law (or even, bemusingly, a strong pro-helmet campaign) might lead to more cycling injuries than are prevented.

    Yes, this is tricky reasoning, and it involves subtle effects, but it’s pretty compelling that the safest cycling countries (Netherlands, Denmark) have huge cycling populations and minimal helmet usage.

  • Ryan

    If you’ve looked at the evidence and concluded that helmets aren’t effective at preventing injury, then that’s cool. I can respect that.

    But I don’t buy the helmet=fear=deterrent argument. That’s just about risk perception, not actual risk; people don’t think a car is dangerous just because it has seatbelts. (They should, but they don’t perceive the risk) Clearly there are people who think riding a bike, with child or without, is incredibly dangerous no matter what you do; the answer isn’t to run away from that perception, but to fight it.

    (Which leads to: If you think helmets *can* prevent injury but don’t wear one because of some social/perception factor, that’s just silly.)

    And while Denmark may be a great ideal to aspire to, we aren’t there yet; Denmark began its pro-bike transition decades ago, and it didn’t happen overnight. We can certainly learn a lot from how they do things, but you can’t just copy the finished product. (Though I completely agree that more cyclists = safer cycling, beyond any infrastructure or safety equipment.)