helmets

Today we learned that U of T researcher Jessica Dennis found helmet laws do nothing to reduce rates of hospitalization for head injury. We can add this to the other studies that have successfully questioned the usefulness of helmet legislation.

There has been a lot of confusion between statistics that show that helmets reduce head injuries and helmet laws which are designed to force everyone on a bike to wear a helmet. While helmets arguably reduce head injuries (although even here there is some contra-evidence), the fallout of helmet laws have been unclear at best and negative at worst. Dennis' study focused on rates of hospitalization across Canadian provinces and compared provinces that implemented helmet laws to those that didn't with their relative hospitalization rates for head injuries. They found little evidence that helmet laws did much to reduce injuries across a population.

Rates of hospitalizations for any cycling-related injury decreased by 28% (95% CI 22.8-33.2) among individuals younger than 18 in provinces with helmet laws and by 22.3% (95% CI 15-29.6) in areas without the laws, "suggesting fewer young cyclists, improvements to cycling safety, or a change in hospital admission policies," according to the researchers.

Hospitalizations for any cycling injury among adults hovered around 10 per 100,000 person-years in provinces with and without the helmet laws, with no significant differences seen.

Despite these decreases, the segmented regression analysis found no "meaningful changes" on hospitalization for head injury.

This study had a narrow focus on just hospitalization and didn't take into account whether people were discouraged from cycling because of helmet legislation. The Ontario Coroner's report on cycling deaths, however, also noted that before implementing a helmet law that the negative effects on cycling need to be also taken into consideration. One problem they found in their review of deaths due to head injuries was that the rate of helmet wearing for young cyclists was much lower than for adults even though helmets are mandatory for under 18 cyclists!

Some research exists which suggest that the health benefits of helmets may be outweighed by the detrimental effects on overall health in the population through the decrease in cycling activity in jurisdictions where helmets have been made mandatory.

The Coroner stressed that because of the possible negative health effects of a helmet law that the Province undertake an evaluation that begins "with a critical appraisal of the existing literature from jurisdictions in which mandatory helmet legislation has been implemented, and the collection of high-quality baseline data on cycling activity in Ontario."

I'm a pragmatic person that thinks that helmet promoters and helmet pro-choicers can co-exist here. I'll happily not bug you for choosing to wear a helmet (or for not wearing one while driving) while taking for myself the freedom to choose when and where I'll wear a helmet. A helmet is like a talisman. It may provide some protection in a limited fashion to a small part of your body, but it has little to no usefulness when forced on a whole population.

Some BC citizens are ramping up a campaign to get rid of the mandatory helmet law in British Columbia. Next year Vancouver will be launching a bikesharing system and this would be a good time to either get rid of the law or exempt bike-sharers. One of the only poorly performing bikesharing systems happens to be in mandatory-helmet haven Melbourne, Australia.

The anti-mandatory activists in BC may be making a very good point as economist Charles Komanoff explained on Streetsblog recently. Mandatory helmet laws are unlikely to make cycling any safer and could actually make things worse by turning people off from cycling (by as much as 20 to 40% in Australian states and cities!). The head protection that helmets give are then outweighed by the poorer health of those who decide not to cycle and a worse 'safety-in-numbers' effect for those still cycling.

Komanoff points out three key areas which helmet legislation proponents ignore:

1. They ignore the possibility that some non-helmet wearers will cycle less or will refrain from taking up cycling in the first place rather than use a helmet or risk being cited for riding bareheaded.
2. They ignore safety-in-numbers, or, in this case, its inverse, by which having fewer cyclists on the road tends to raise per-cyclist crash rates with motor vehicles, as cyclists’ diminished presence on the road leads drivers to treat them as aberrations rather than as part of traffic.
3. They overstate helmets’ protective value in reducing injury severity in the event of crashes.

In the following two photos it's actually the father and daughter without helmets on Dutch separated lanes, and not the woman with the helmet and safety vest in the middle of Brussels traffic who are likely to be safer. Infrastructure and behavioural changes (such as in the Netherlands) have had a bigger impact on safety for cyclists then mandatory helmet legislation (such as in Australia).

Helmet legislation certainly has the intended effect of increasing helmet usage. But as Komanoff shows in his chart, it can be easily offset by the decrease in the safety-in-numbers effect. Part of the confusion in all this lies in the fact that proponents have assumed what is true in case-control studies is also true across a society. Case-control studies have suggested that cyclists who choose to wear helmets usually have fewer head injuries than non-wearers. The same is not true for a society where helmets have been made mandatory. Before and after data show enforced helmet laws discourage cycling but produce no obvious response in reducing the percentage of head injuries. Dr. Dorothy Robinson looked at all jurisdictions that had introduced legislation and increased use of helmets by at least 40 percentage points within a few months: New Zealand, Nova Scotia (Canada), and the Australian states of Victoria, New South Wales, South Australia, and Western Australia. When looking at head injuries he found that there was no clear evidence that the reduction in head injuries can be attributed to helmet laws. In all cases head injuries were dropping anyway. Robinson also found that in Australia cycling rates were increasing before helmet laws put the brakes to it.

The reasons helmet laws aren't working may be partly due to risk compensation where people feel that they can take greater risks when wearing a helmet; they might be wearing the helmet incorrectly. Some of the researchers also made incorrect adjustment for confounding variables in case-control studies where they misjudged how much of the effect was due to helmets.

Helmets also aren’t very effective in reducing injury damage to cyclists who are struck by cars, one of the main reasons to wear one in the first place.

The most authoritative epidemiological analysis of helmet efficacy to date, a study of 3,390 cyclist injuries reported from seven Seattle-area hospital emergency departments and two county medical examiners’ offices, summarized in Injury Prevention in 1997, found that helmet-wearing conferred only a 10 percent reduction in severe injury rates; and even this small differential fell below the threshold of statistical significance. What makes this analysis especially noteworthy is that it effectively invalidated the authors’ premature and incomplete conclusion in their decade-earlier study that helmets were spectacularly effective in reducing the chances of head and brain injuries; it was that “finding,” which has reverberated around the medical echo chamber ever since, that catapulted helmet promotion to the fore of bicycle “safety.”

And this isn't even taking into account the health benefits of cycling. A person who decides to avoid cycling is likely a person with an increased health risk due to inactivity and obesity. As Professor John Pucher points out:

“All scientific studies find that, even using conservative, understated estimates of the health benefits of cycling, they far exceed any traffic risk,” explains Pucher.

The exact ratio varies from city to city and from country to country, but the health benefits of cycling are at least five times higher than the traffic risks, and in some countries, such as the Netherlands and Denmark, the ratio is almost twenty-to-one.

So here's to having the choice of wearing a helmet or not. You can reduce the risk of a head injury for yourself by choosing to wear a helmet (though helmets are less effective when you're involved in a collision with a car). However let's not turn away people from a healthier lifestyle just because they don't want to wear a helmet. The risk of bad health is much higher for those who are sedentary than for those who cycle, helmet or no helmet.

If you're a CBC Radio nerd like me you might have heard a renewed mandatory helmet debate this morning with the news that a cyclist died from "life-threatening head injuries" in a crash a month ago at Caledonia and Davenport. The media and police have jumped on the fact that the cyclist was not wearing a helmet.

Police claim they discovered that "the severity of the head injury indicates that he was not wearing a helmet". (I wonder why they couldn't discover he wasn't wearing a helmet by just looking for an absence of a helmet in the area. I also wonder why the media is taking the police's take on the cause of head injuries when this is normally the role of health professionals.)

The man was riding southbound at Caledonia Park Road "at high speed" as he approached a green light on Davenport, according to police.

When the light changed, the man made a sharp left turn eastward onto Davenport's westbound lane, and then lost control and fell onto the roadway.

Police also issued an advisory in the Monday release that said: "While helmets are not mandatory for those over [18], Traffic Services would remind everyone that helmets are your best defence against brain injuries that result from falls. Parents need to be vigilant in ensuring children wear their helmets at all times when riding their bicycles."

This news follows a study at the University of Manitoba that helmet legislation works to get more people to wear helmets (while also reducing the number of people willing to bike).

While it is often a good idea (in my opinion) for an individual to wear a helmet to reduce the chance of a head injury, the broad statistics are not clear if helmets help all that much. We should not arrive at a conclusion and decide policy based on these individual cases where people have head injuries. It is known that helmets are of very limited value in the event of a collision with a car; and many cyclists negate the protective effect of helmets by taking more risks. The promotion of helmets implicitly shifts responsibility of care to the cyclist and away from drivers, and away from the provision of safer streets by means of street calming or bicycle facilities.

The truth is, strong calls for mandatory helmet legislations happen mostly in countries - such as United States, Canada, Australia - where the cycling modal share is very low and where injuries and deaths per kilometre travelled are much higher. It's not hard to argue that a big reason for this is that it's easier to shift the blame onto cyclists rather than taking effective steps in configuring our urban spaces to accommodate cyclists and pedestrians.

Source: www.cyclehelmets.org/

What we can take away from this is that helmet wearing is only a tiny part of the overall picture. We must look to other elements of cycling policy in countries where injury/death rates are low; elements such as bike lanes/paths and early cycling education.

The Toronto Star has discovered that one can be fashionable on a bike (which is not the same as saying a particular bike is fashionable), thanks in part to the Curbside employees and thecommonelite.org bloggers, Gillian Goerz and Mikey Bennington.

“The city lends itself to cycling because it’s predominantly flat and there is a great street culture with lots of people outdoors,” says Goerz, who also works as an illustrator. “It’s also spread out with different cultural centres (that are) easy to get to on bikes.”

Another reason style and spokes are suddenly in sync could be bike-sharing programs such as Vélib’ in Paris and Bixi in Montreal (and Toronto next spring), which offer spontaneity to bike riding. That means you’re not dressing to go for a ride; rather, you’re dressing for your destination, whether that’s a gallery opening, dinner with friends and, yes, even a night out at the clubs or a bar. The bike just a cab as the mode of transport.

That’s why it’s not unusual to see girls wearing miniskirts and platforms while pedalling.

“Just because you’re riding a bike, you don’t have to lose your femininity,” says April Wozny, a Toronto publicist who will ride to her meetings on a bike she bought for $100 and calls Big Blue Buttercup.

A strange story came out of Wisconsin today. A student falls off his bike while braking to avoid a truck. The truck runs over his head, crushing his helmet, but leaving him with little more than a concussion.

"I didn't see it coming, but I sure felt it roll over my head," he said. "It feels really strange to have a truck run over your head."

As the helmet debate continues, and it will, we can be sure we'll hear this story come up as an anecdote in favour of helmets. Quite often though, the debate is not so much about whether helmets are useful or not, but whether or not they should be required by law or simply encouraged.

While I'm at it, here's one more take on helmets from Momentum Magazine.