Bad science and helmets

The Post has a couple of helmet articles today, one about why you should wear a helmet and the other about why bikeshare doesn't provide them.

The first article argues that since an overwhelming majority of cyclist deaths between 1994 and 2010 involved cyclists who were not helmets, that is all you need to know to know that you should always wear a helmet. There is a case to be made for wearing a helmet (I usually do and I think you're probably better off doing so), but this isn't it. Rather than write a reply, I'll just point you to Crikey's excellent comment:

While I do recommend wearing helmets, this pie chart proves nothing. The pertinent fact would be the percent who wear helmets and their relative survival rate, not the overall relative survival rate. What's more, a more rigorous look at the actual research shows a statistically significant but fairly modest, and overall somewhat unclear, impact on head injuries. Finally, helmet design is done in accordance with federal standards that have not kept up with the findings of more recent studies. It's possible that helmets could be much better, but there is no incentive, and some disincentive, to making them so.

And to that I'll add that the data that the pie chart is based on is dubious at best. 

this data is based on Police Accident Reports and many of these do not include a separate entry for bike helmet use. So the FARS data is based on the crash narrative. If no information is given, it should be listed as unknown.

Unfortunately, it appears that nearly all of these cases that should have been coded as "unknown" (including a considerable number where the bicyclist actually was using a helmet, but such usage was either never noted or overlooked in the narrative) were instead coded as "not used"

One strong indicator that the FARS bicycle helmet use data should not be fully trusted is the fact that the "unknowns" are so few in number. It is simply not credible that a low priority data element such as bicycle helmet use would have a precision associated with it that is a factor of 20 better than that seen for much higher priority data elements such as seat belt or motorcycle helmet use (0.5% "unknowns" vs. 11% or 10%)

The second article, by child-of-rabid-R.E.M.-fans Leonard Bernstein, is a pretty alarmist article about not wearing helmets on Capital Bikeshare. He relies largely on the stat debunked above and the somewhat discredited, but widely repeated 1989 study. You can read about the criticism of that study here. Even the NHTSA has admitted that the study isn't robust enough to meet the standards of the Data Quality Act. 

Though he starts with the claim that the stats on bicycle helmets are abundantly clear, he undermines his whole case that bikeshare riders need helmets later on.

In four years, there have been no reports of a major injury to a Nice Ride Minnesota cyclist, Dossett said, and no head injuries at all. Much the same is true for Washington’s Capital Bikeshare program, which has had fewer than 100 reported crashes since 2010, despite 6.8 million bike trips, said Kim Lucas, the program manager.

And his claim that "Seattle and Boston have found ways around" the problems related to providing bikeshare users with helmets is not accurate. They have programs they are going to try. They have not shown that they will solve the problem, or that the helmet vending business is worth the expense.

Holly Houser, executive director of Pronto Cycle Share in Seattle, said the helmet vending machines added about $850,000 to the $4.4 million that will be spent on bicycles, docking stations and other equipment.

“It would be much easier if we did not have the mandatory helmet law,” she said. “We all know that.”

Seattle's bike share system will be the first in the US to go into place in a city with a mandatory helmet law. We'll see how much that impacts ridership. 

The answer to the question raised by the second article "Why don't bikeshare programs provide helmets?" is pretty clearly that, since injuries are so rare, it isn't worth the price. 

Comments

[jeffb]

Years ago the answer to preventing rapes was for women to wear modest dress and restrict their movements to daylight hours.

Has lack of helmet usage become a blame the victim strategy to avoid doing the real, and more expensive, work of making our streets safer?

[DE]

We rented bikes in San Francisco last week to bike across to the Marin Headlands, and the rental place (not the citywide bikeshare) did offer helmets. The girl took one, and I did not. They were a bit manky looking, but I didn't mind them offering them as long as it wasn't mandated. Harder to do without real people, but not impossible. I don't think it's necessary, but if it would make some people more comfortable, they could try it on a trial basis at a couple of stations.

[freewheel]

This article is pretty good at debunking pro-helmet stats, as well as asking why, if helmets are so effective, drivers and pedestrians aren't wearing them.

[freewheel]

Let's give that URL another shot:
http://www.howiechong.com/journal/2014/2/bike-helmets

[DE]

I've been trying to figure out how they'd do helmets as a trial at a couple of stations since you can return the bikes at any stations and you'd need helmet returns. I am stumped so retract the stupid idea.

[dynaryder]

Love the helmet examples in the first article. I have a Bern;it only gets used when the temps dip below 30. Wearing one of those downtown in July is asking for heat stress. And that folding helmet isn't even approved for sale yet. Uftda.

As for the second article,does anyone know if the CaBi rider has head injuries? I tried a quick Google but couldn't find anything. A helmet really isn't going to do much if a car hits your body.

[washcycle]

Yeah, I wondered the same thing. Does he even have a head injury?

[jaime]

jesus, i hate helmet threads. i mostly ride with one. it seems every time i rubber up without one on, my poor noggin gets pretty cut up. that, alone, for me, is reason enough to wear one.

they(helmets) don't seem to prevent concussions(at least, the time i was hit by a car and wearing one, the ensuing nausea told me i had a pretty good concussion(or the nausea was the result of a massive dose of painkiller in the back of the ambulance.....).

some argue that the use of helmets may encourage more dangerous riding in places where you shouldn't be riding aggressively(i don't mean angrily...). though, i feel as if i've been more careless in my riding when not wearing one. i find, personally, that i fall into the more natural gogogogogo style i have most of the time when i ride. when i'm riding with a helmet it's usually in an environment in which i can ride faster(i don't race, but do like speed) and don't have to be as cognizant of passersby or other vehicles.

if i'm in an urban area, which is more the case lately, i tend to go back and forth with my helmet use. if i'm just going a few blocks, i may not use it. but, many accidents happen close to home. being aware of that may lend to a heightened sense of caution, personally speaking. for many, it may make them too comfortable and lackadaisical.

IDK, wear one if you want, or, don't if you don't want. it's a mixed bag for myself, obviously.

[Mike]

man, think of the infrastructure improvements you could get with the $850,000, if it hadn't been wasted on a helmet vending machine. And *thost* could actually improve cyclist safety.