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Comment by apendleton | Hacker News Reader

Argh, this kind of anecdotal evidence makes me crazy. Helmets aren't skulls. You have no idea whether the forces that caused the helmet to crack would have caused similar injury to your head had you not been wearing the helmet, nor do you have any idea whether the forces the helmet managed to absorb before failing are a significant fraction of the forces your head experienced during the accident. Nothing about your experience is sufficient grounds for the conclusion you draw at the end of your comment (that "they have to work to some extent"), nor can any single accident experience provide such grounds.

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Let me rephrase that - if I, somehow, had to be in that accident again and fall head-first to the pavement, I would once again choose to be wearing a helmet, and I don't need a scientific research to make that choice. If you don't like that it's anecdotal - well, I can't help that.

And I think that hitting the pavement with the helmet instead of my head is indeed how the helmet should work, so it most certainly "works to some extent".

Unless you want to argue that I would have been just as fine hitting the ground at 25km/h without a helmet?

Or is your entire(and only) point that no one should ever mention anything they have ever experienced unless they can back it up by research by an approved institution?

"Unless you want to argue that I would have been just as fine hitting the ground at 25km/h without a helmet?"

Why not? Humans are pretty resilient. Maybe you wouldn't have, but I see no reason to dismiss so easily the possibility that you might have been fine.

Mentioning personal experience is fine, but you shouldn't make broad statements from it unless the experience actually justifies it.

Think of it like this: somewhere out there is a story that's the opposite of yours. Some guy wrecked his bike and hit his head without a helmet and was fine afterwards. He then concludes that helmets don't work. His reasoning is no different from yours, yet reaches the opposite conclusion. Clearly the reasoning must be flawed.

I am your guy hitting his head after a cycling accident and being fine afterwards. Would it surprise you that, in spite of being fine, it is right AFTER this accident that I decided to start wearing a helmet? Judging by your argument, you would call me illogical.

Why would I call you illogical? Did you conclude that wearing a helmet was a good idea based solely on your anecdotal experience, completely ignoring wider realities? Or did you actually think it through and not base your conclusion on a single event?

Somehow, I love this response.

Sometimes we get a little too caught up in the science. Good to hear a little plain ol' common sense from time to time.

Argh, this kind of arguing makes me crazy. It makes it seem like your only reason for commenting is to make yourself feel superior.

Can you seriously say that it would be better to fall on your head and scrape along the pavement without a helmet?

I would prefer to slide along my helmet, not my skull.

So, "they have to work to some extent" is an entirely reasonable thing for him to say. Either I lose some hair and skin or I scrape a helmet. It's obviously doing something. Common sense.

Some people overlook the potential for concussions or traumatic head injuries, anything except massive skull damage, when considering safety headgear. Cycling is a very diverse activity and many only consider safety issues they expect to encounter.

There are other factors to consider, though.

First, wearing a helmet is going to alter the kinetics of your head during the accident, possibly for the worse.

Second, wearing a helmet can alter the behavior of people around you in ways that impact your safety. For example, car drivers may drive less carefully around a helmeted rider.

Third, wearing a helmet can alter the behavior of the wearer.

Now, does that mean that helmets don't improve safety? I would guess they probably do. But let's make the argument based on sound reasoning and data, not insults and "common sense".

You had been downvoted at the time of my reply. I don't know why - you make some good points.

> But let's make the argument based on sound reasoning and data, not insults and "common sense".

I strongly agree. When someone talks about homeopathy it's easy to dismiss it as nonsense, and we only need a few studies to tell us it's nonsense. But when someone makes a calm, sensible claim with a reasonable method of action ("helmets protect the brain") it's more important to get good quality science to investigate these claims, to eliminate our biases and to eliminate confounding factors.

Imagine a crash where someone's head scrapes along the ground. Now give that person a helmet. With the wrong materials the helmet will "snag" the ground. This could mean that the head sticks while the body keeps going, risking severe spinal injury.

While the science around driver perception of helmet-wearing cyclists is weak it's a reasonable statement - "drivers give less room to people wearing helmets because they assume a better rider". That could be testable in driving simulators, and that would give use good quality data.

It's nice to hear anecdote. "I wear a helmet because ..." or "I don't wear a helmet because ..." are good things to hear. It gives context to the data and the science. But these are not reasons for everyone to follow the advice.

It's fun to watch a crowd of nominally intelligent people so thoroughly mix up arguments with the conclusions.

If you make a bad argument in favor of wearing helmets, then it's a bad argument regardless of whether helmets are effective. But the moment you call it out, you get nothing but people talking about how irresponsible you are for recommending people not wear helmets.

The exact same thing is going on over in the Arafat discussion. People make crazy arguments about how Arafat (or other people) was killed and then, when called out on it, act like it's the conclusion being attacked, not the reasoning.

I agree, the lack data really makes it _impossible_ to decide who is in the right here. I propose an experiment: go ram your head into a brick wall with and without a helmet. (To reduce the variance of your estimate, you'll probably want to perform ~10ish trials.) Then report back, and we'll finally get to the bottom of the extremely nagging and tough to judge question of whether wearing a helmet is an improvement when it comes to smashing one's skull into inanimate objects.

I guess I would trust common sense in this case. I mean I've been hit in the shins with a hockey puck while wearing shin pads a few times, they seemed to work. This is anecdotal, but I don't think a double-blind study is needed to show that shin pads protect your shins from hockey pucks.

The double blind study is to rule out other factors - are tackles more aggressive when players are wearing armour, and thus more risky?

So, with helmets: Do they increase risk of neck and spinal injury by causing weird head movements during impact with floors? and etc.

I personally know people who object to helmets, and refuse to wear them even though we have a helmet law in my city.

I'm not entirely in agreement, but there is logic to this line of reasoning:

1. Helmets, and helmet laws give the impression that cycling is a dangerous activity, and discourage people to cycle.

2. the biggest thing you can do to increase the safety of cycling, is create cycling infrastructure and put more cyclists on the road (I believe this is backed up by hard data, but I have no citations).

3. It follows from 1 & 2 that helmet laws make cycling less safe for all of us by decreasing the number of cyclists on the road.

There is more to their argument than that, but that's the one I personally find most convincing. I still wear a helmet though, so clearly I'm not entirely convinced.

As a side note, research has shown it may be safer in the sense that drivers give more birth to helmet-less cylclists. They see those with helmets as more professional and better equipped, and apparently pass them at higher speeds and closer clearances.

http://www.drianwalker.com/overtaking/overtakingprobrief.pdf

As for a more broad discussion on the topic, outlining both sides of the debate:

http://www.cycle-helmets.com/helmets-uk-dec-2012.pdf

I don't give 2 shits about the drivers that pay enough attention to see what I'm wearing. I care about the drivers not even looking.

Your first point is a strange one. Are you saying that cycling is not dangerous enough to warrant wearing a helmet? If so, then the other points are moot, and you could have simplified your argument to just "there's no need to wear a helmet".

If on the other hand, you believe that cycling is dangerous enough to wear a helmet, then you're effectively saying that people shouldn't wear them in order to 'lure' other potential cyclists into cycling. That's just ludicrous!

Its sort of a mixed bag:

So if they can help reduce injury, shouldn’t they be mandatory, just like motorbike helmets? Australia tried it in the early 90s and the result was a 15 to 20 per cent drop in the number of hospital admissions for head injuries. That would have been great, but it also reduced the number of cyclists by around 35 per cent.

----

A recent study in the British Medical Journal showed that cycling has a positive health impact around 77 times larger than the potential for serious injury; essentially, there’s a small chance that you’ll come a cropper, but a very large chance that you’ll reduce your likelihood of suffering mental illness, heart disease and obesity. That means the laws were hugely counterproductive

[Personally, I wear a helmet, though.]

actually, it has been shown in the Netherlands that wearing the helmet is yes safer, but laws requiring helmets discourages some people from riding out of a variety of reasons. In aggregate, the GP is stating that looking at the cycling system in light of greater participation is a more effective/better solution than requiring helmets.

http://policy.rutgers.edu/faculty/pucher/Irresistible.pdf

Number one is backed up by the Australian experience of compulsory helmet laws.

Number two is backed up by the dutch experience (hint, it hasn't always been like that).

I wear a helment when I am unsure of the safety of cycling conditions on my planned route, or on an unknown route. Otherwise I don't.

It would not necessarily be inconsistent to oppose mandatory helmet laws while wearing a helmet oneself.

I'm not sure what I think about the laws. But I do question the claim that helmet laws are primarily responsible for the drop-off in cycling in the US over the last several decades. I would want to see some strong evidence for that before accepting it. Just off the cuff, I would expect it has more to do with the fact that people prefer cars, and that US government policy is to keep the price of gas as low as possible.

>create cycling infrastructure and put more cyclists on the road //

I think you mean put more cyclists on dedicated cycle lanes segregated from traffic. Surely they're far safer than mixing cyclists with automobiles.

Mildy humorous anecdote: First and only time I've hit my head cycling was my first time out wearing a helmet, hit a low branch as I'd not allowed for the extra clearance.

Ah, by "on the road" I meant out and about, not specifically on the street. By "cycling infrastructure" I meant separated bike paths and lanes.

In the places of the world that ordinary people use bikes for everyday transportation they do not wear helmets and cycling is safer.

Cycling is safer while wearing a helmet but so is wearing a helmet while walking and driving and shitting and eating a fucking sandwich.

He probably would have received a mild to moderate traumatic brain injury. The common case for a moderate injury is a year or three of recovery, if you're reasonably lucky.

HN can get just weird sometimes.

Next week: "I stood on a rusty nail and my foot got sore, I'll try not to do that again" guy gets taken apart for not standing on 1,000 nails in a double blind study to get statistically significant results of nail-standing-induced badness. And no, I don't know how one would introduce the double blind element either :-)

Honestly, sometimes sharing experience and telling stories is just that. Wish HN would stop picking on people for such contributions.

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