Helmets

[drossall]

... but on the whole the helmeted head proved to be safer in the majority of cases...

Although according to Robert Davis's Death on the Streets, motorcycle casualties increased in the year after helmets were made compulsory.

[Fonant]

Suggest anyone who is anti helmet does a few shifts on work experience in a casualty unit.

But then you won't see all the people who crashed without helmets and so didn't need to go to casualty

I would be interested to know what percentage of all head injuries at casualty were cycling-related. I think I read somewhere that car crashes cause many many more head injuries - but no need for car helmets?

For a polystyrene hat to work to its fullest potential it has to end up crushed but still in one piece. So often you hear "the helmet was destroyed, lots of pieces", which, as any materials scientist will tell you, meant that it absorbed very little impact energy.

Even at best, a polystyrene hat absorbs the energy present in a normal head hitting a flat surface from a height of around 2m, i.e. a cyclist falling off their bike at slow speed or a pedestrian tripping up.

http://www.helmets.org/stdchart.htm
http://www.cyclehelmets.org/papers/c2023.pdf

(The more I research helmets, the more amazed I become at how poor they are!)

[Fonant]

Just one point though, how many times has anyone made more effort to keep their head off the road in a spill,these two went down like a ton of bricks as the front wheel shot from beneath them.

If your head is two inches larger in diameter, and slightly heavier than normal, then it will be more difficult to keep it from hitting the ground. On falling I would hope to keep my head just off the road (and yes, I've managed this, including falling off a tandem on black ice!), but if my head + hat is that much bigger I wouldn't have a chance.

[reohn2]

Just one point though, how many times has anyone made more effort to keep their head off the road in a spill,these two went down like a ton of bricks as the front wheel shot from beneath them.

If your head is two inches larger in diameter, and slightly heavier than normal, then it will be more difficult to keep it from hitting the ground. On falling I would hope to keep my head just off the road (and yes, I've managed this, including falling off a tandem on black ice!), but if my head + hat is that much bigger I wouldn't have a chance.

I see what your driving at ,I just don't agree.

[drossall]

This discussion has been surprisingly short of overall perspective, and rather focussed on one study that most on both sides of the debate seem to regard as a bit of a side-show.

Personal anecdote is a bit of a problem, simply because there is so much of it in favour of helmets. About 120-140 cyclists a year are killed in the UK. That's an horrific figure, but a fraction of the total c3500 road casualties. Then think that many of these people would have suffered injuries so severe, and not limited to heads, that helmets could not have saved them. Hence the maximum saving is 30-60 lives, if helmets are as effective as their most extreme advocates would have us believe. Even with that assumption, knowing someone whose life actually has been saved by a helmet is maybe 50-100 times less likely than knowing someone who has been killed in a road accident of any kind, yet some of us seem to meet loads of such helmet beneficiaries every year.

"Real" evidence falls broadly into two kinds. Hospital studies look at casualties brought in, whether helmets were worn, and the severity of injuries. Such studies come out generally in favour of helmets, although the most extreme results are known to be worthless. The famous study that came out with helmets preventing 85% of head injuries turned out to have compared rich helmetted kids riding off-road with a high likelihood of reporting to hospital for any significant injury with poor kids playing on urban streets and having neither health insurance nor helmets. The more impressive studies in this group compare other injuries as well, in an attempt to eliminate such bias. There is a difficulty that the relative rarity of severe cycle casualties (see above) makes it difficult for one or even several hospitals to gather statistically significant numbers.

Population-level studies look at national casualty trends before and after helmet compulsion (or widespread adoption). The first studies on this in Australia claimed significant success for helmets, until it was pointed out that the law had been followed by falls in levels of cycling of about 45% (of which more later) and that this easily accounted for all the reduced casualties. Once adjustment was made for this, results began to show no benefit or, more alarmingly, an increase in the per capita risk. So far, three credible explanations have been offered for this, to two of which, risk compensation and rotational injuries, reference has already been made.

The third is that helmet campaigns scare people off bikes by emphasising the risks of cycling, even though on any reasonable risk-benefit analysis cyclists win hands-down. However, increasing the number of cyclists has been shown to be the most reliable way of reducing the risk to each individual (presumably because drivers get used to looking out for them), so anything that frightens people off cycling has to be bad news of the most direct kind.

[drossall]

If your head is two inches larger in diameter, and slightly heavier than normal, then it will be more difficult to keep it from hitting the ground.

I see what your driving at ,I just don't agree.

I remember watching one first-stage sprint crash in the TdF a couple of years back. A victim in the bunch tucked and rolled, as you'd expect. I got the strong sense that his helmet was going to muck that up.

I've just said my piece on anecdotal evidence, and that's as anecdotal as it comes. However, it makes perfect sense to me that millennia of learned tuck and roll response would not be helped by modifying head size, and direct impacts must be pretty rare in bike crashes unless you actually hit a wall.

[thirdcrank]

I speak (as I have said often before) as someone who has no faith whatsoever in helmets, but do not want the hassle for me or my survivors with the victim-blamers.

However, let us suppose that even your maximum estimates for lives saved are a big exaggeration and reduce the figure to 15. I imagine there are many who would wear a helmet just to avoid those odds.

[drossall]

Certainly. However, my figure was mentioned in the context of anecdotal evidence. I said nothing to confirm that a figure of even 15 is correct. There is also anecdotal evidence in the opposite direction. I have seen at least one heartfelt posting regretting persuading a relative to wear a helmet because of the neck injuries that followed.

Hence, I was trying to steer anyone who read what was admittedly a rather long post towards the statistical evidence as being more reliable. It is not, however, unequivocal. Again, you may feel that it leans towards wearing helmets being more risky than not doing so - or you may take the opposite view.

In other words, the figure could even be, say, 3 to 5 in the opposite direction. Would you then give up helmets to avoid those odds?

It seems extremely difficult to draw a conclusion sufficiently strongly to advise anyone else with much confidence.

[Fonant]

However, let us suppose that even your maximum estimates for lives saved are a big exaggeration and reduce the figure to 15. I imagine there are many who would wear a helmet just to avoid those odds.

Sadly, yes, but that's the problem - no-one really understands risk. If I said you could probably reduce the odds to 10 deaths per annum by wearing motorcycle helmets, the "if it only saves one life it must be worth doing" argument would say that we should all wear motorcycle helmets. Taken to the logical conclusion, you could achieve zero cyclist deaths just by stopping everyone from cycling.

[axel_knutt]

It's nice to find someone else who's actually read Adam's at last. If the others read it they would also find out some of the pschology of why debates like this go round in circles with different parties just talking at one another.
As Adams points out, there are more elderly pedestrians with head injuries than cyclists of all ages, but the campaign to make pedestrians wear helmets is curiously inconspicuous.
In spite of all the safety devices and legislation total accidental deaths have not declined in the last century.

[reohn2]

... but on the whole the helmeted head proved to be safer in the majority of cases...

Although according to Robert Davis's Death on the Streets, motorcycle casualties increased in the year after helmets were made compulsory.

But was that because motorcyclists were wearing helmets or some other reason,do you know?Or are we to assume by your statement that the reason for the rise is because they wore helmets.

[reohn2]

If your head is two inches larger in diameter, and slightly heavier than normal, then it will be more difficult to keep it from hitting the ground.

I see what your driving at ,I just don't agree.

I remember watching one first-stage sprint crash in the TdF a couple of years back. A victim in the bunch tucked and rolled, as you'd expect. I got the strong sense that his helmet was going to muck that up.

I've just said my piece on anecdotal evidence, and that's as anecdotal as it comes. However, it makes perfect sense to me that millennia of learned tuck and roll response would not be helped by modifying head size, and direct impacts must be pretty rare in bike crashes unless you actually hit a wall.

In the last 30years I've fell off the bike twice and I've never been hit by a car.You talk of tuck and roll and I agree it would be a good strategy,but on the two occasion that i fell(both on black ice) the only thing I thought was,"what th...." and it was all over with.I hadn't even the time to think "tu..". How does one practice.

Lets be honest theres the wills and the won'ts the dos and the don'ts.I will and do.I respect those that don't and I'll fight for the rights of the don'ts not to.But I won't be swayed not to.That is not all the time anyway.

[Fonant]

In spite of all the safety devices and legislation total accidental deaths have not declined in the last century.

In risk terms, society in the UK seems to have decided that killing ten people and injuring thousands on the roads every day is an acceptable cost for the benefits of our road transport freedoms. Without changing society's cost/benefit balance, I think Adams suggests that whatever we do to try to increase safety the same number of people will die. Probably different people, but still ten a day on the roads.

Any safety improvement is generally turned into a performance gain: ABS brakes and high-grip road surfaces mean we can driver faster and brake later, seatbelts and airbags mean we can drive a little less carefully, etc. That's why drivers hate speed cameras, they're a safety improvement that has no potential to be turned into a performance gain.

[reohn2]

In spite of all the safety devices and legislation total accidental deaths have not declined in the last century.

In risk terms, society in the UK seems to have decided that killing ten people and injuring thousands on the roads every day is an acceptable cost for the benefits of our road transport freedoms. Without changing society's cost/benefit balance, I think Adams suggests that whatever we do to try to increase safety the same number of people will die. Probably different people, but still ten a day on the roads.

Any safety improvement is generally turned into a performance gain: ABS brakes and high-grip road surfaces mean we can driver faster and brake later, seatbelts and airbags mean we can drive a little less carefully, etc. That's why drivers hate speed cameras, they're a safety improvement that has no potential to be turned into a performance gain.

I agree with every word of that.

[Simon L6]

This discussion has been surprisingly short of overall perspective, and rather focussed on one study that most on both sides of the debate seem to regard as a bit of a side-show..........
.

David - thanks for the lucid exposition.

I do think that it's possible for intelligent people to choose to wear a helmet or not to wear a helmet. I go back to my first post. The CTC is simply anti-cpmpulsion...