Helmets - the definitive thread.. ** Mod Note - Please read Opening Post **

smacl wrote: »

I then see further posts suggesting any first hand anecdotal accounts should be dismissed as invalid

I don't think that was the point. Another point was made, along the lines of: "Look at all these stories of people hitting their heads and being sure the helmet saved their life", together with the claim (made by only one poster) that such a body of claims was as good as real-world evidence could get.

From a scientific point of view, these are essentially anecdotes, and not regarded as especially good evidence. Expert testimony without reference to studies isn't that high up the list of highly compelling scientific evidence either. What is well-regarded is large bodies of quantitative data measured as objectively as possible. Not that anecdotes and expert testimony are wrong, as such, just that they need to be backed up with solid, objective data.

Archie Cochrane's long campaign to stop consultants in the UK justifying practices by saying things like "Of course, I'm right. I'm the head of surgery at Saint Bartholomew's!" is an interesting story.

bedirect wrote: »

we listened to all these debates when wearing seat belts became mandatory, i know people who have crashed & definitely the helmet saved them. It is very easy to fracture your skull

Nobody is arguing with that. What people are saying is that an impact that can fracture a skull normally far exceeds the reasonable performance expectations of helmets currently on the market.

smacl wrote:

What I'm seeing is are many posts saying the following; you probably won't be in a bike accident. If you are you probably wont hit your head. If you do hit your head the helmet probably wont help you much. And anyway, wearing helmets is bad for the cycling community.

I don't see those various statements (which I agree have each been made in one form or another) being tied together in this thread to support an argument against wearing a helmet. Where references to the likelihood of an accident occurring, and the cyclist hitting their head, are made I think they've been in response to the suggestion that cycling is inherently dangerous, which is a suggestion strongly implied by those that consider a helmet to be essential. It's a matter of opinion, but I don't see the individual statements as being at the opposite end of the scale to the "helmets are essential" views, I see them as being a lot more moderate and trying to drag the debate back to a reasoned middle ground and away from the very emotive "you'll die without a helmet" arguments. Linking the statements together as if each implied the next though, would certainly form an argument that's heading to the far end of the scale, in my view, but I don't think that has actually happened.

As regards the dismissal of anecdotes, I agree with tomasrojo's post on that, anecdotes are interesting but when things get emotive they can get casually elevated to the level of fact, which hinders the debate rather than helps it. The core of the debate can end up being lost as supposed facts are challenged and counter-challenged.

tomasrojo wrote: »

I don't think that was the point. Another point was made, along the lines of: "Look at all these stories of people hitting their heads and being sure the helmet saved their life", together with the claim (made by only one poster) that such a body of claims was as good as real-world evidence could get.

From a scientific point of view, these are essentially anecdotes, and not regarded as especially good evidence. Expert testimony without reference to studies isn't that high up the list of highly compelling scientific evidence either. What is well-regarded is large bodies of quantitative data measured as objectively as possible. Not that anecdotes and expert testimony are wrong, as such, just that they need to be backed up with solid, objective data.

Archie Cochrane's long campaign to stop consultants in the UK justifying practices by saying things like "Of course, I'm right. I'm the head of surgery at Saint Bartholomew's!" is an interesting story.

You're embellishing what i said a little. I said injury reduction and not life-saving.

There is a distinct lack of the objective data needed that is very true.

I'm with you on the consultants thing...partially why I disagree with a lot of the info referred to earlier on cyclinghelmet.org...it's biased opinion with an academic sheen.

galwaycyclist wrote: »

With regret you walked yourself straight into that role. The drunk man under the streetlight story is a common illustration of observational bias. You have apparently argued that our observations should be biased. Your apparent argument is that we should isolate our observations to individual collisions without considering the wider evidence such as injury trends among populations where helmets are more common.

To illustrate it another way. Your argument is equivalent to saying that doctors should continue to prescribe thalidomide to pregnant women on the basis that there is laboratory evidence showing it is good for morning sickness. Under your reasoning, we would ignore any evidence of unintended consequences - such as birth defects - because it was being seen at a population level and is difficult to characterise or fully explain.

Is that an ethical or moral approach?

That would be well and good if you had any evidence of negative consequences for an individual if they wear a helmet (that outweigh the potential benefits).

Your streetlight theory is a poor cop out from a good argument.

Helmets can be considered similar to prescribed medicines and their known side effects. Generally the benefit of approved medicines outweighs the negatives like the protection by helmets provided outweighs the risk of rotational injury or a wider effective head size. Thalimide was a gross failure of the regulatory system but where your analogy fails is that the effects were on an individual basis. The women had no morning sickness but most did have babies with birth defects.

If I leave my helmet at home it won't get some lazy f*cker off the couch and into a healthy lifestyle.

smacl wrote: »

..... Say we see 20 such posts per annum, out of a population of say 1000 contributing boardsie cyclists. (Picking numbers out of the air, for sure, but roughly the right order of magnitude). That gives us a 2% probability of such an event happening to any given cyclist, in any given year. ......

This makes me think I need to put back on the stabilisers I tend to fall off about once a year and generally manage to bang my head when I do so. I think it must be old age - when I was in college about thirty years ago, I cycled more or less the same amount, considerably more recklessly, with poorer quality brakes and tyres and never fell off at all.

In response to an earlier post asking about experience in other sports, I kayaked for many years and always wore a helmet. But then again you'd find yourself upside down in a kayak a lot more often than you'd fall off a bike. I rarely wore one sea-kayaking but always when surfing where again the risk was being washed along upside down with the potential for smacking your head on the sea bed or a rock. On the other hand I never wore a helment during my pathetically short hurling career.

Now you're really stretching it...individuals as part of the population ...back to australia again too...fumbling in the dark?

Helmets are one thing but I'm not giving up my lycra!

I have even been thinking about commuting in a skinsuit for more strava glory

Is there a voodoo ritual I can practice as I cast away my helmet in favour of the greater good?

galwaycyclist wrote: »

Regarding seatbelts Monkeybutter writes:




Just to deal with this.

Studies of crashes, experiments with crash death dummies and human cadavers predict that wearing seatbelts should prevent death in crashes that would otherwise be fatal.

This source suggest a 72% reduction in mortality among wearers of lap and shoulder belts.

http://aje.oxfordjournals.org/content/153/3/219.full

For the sake of keeping our numbers clean I am going to assume 60%. So starting at 0 if we get 25% of car occupants to wear seatbelts deaths among that group should go down by 15%, if the wearing rate is 50% we should get a 30% reduction and so on.

Irish road deaths in 1979

The numbers that follow come from Irish offical publications. In 1979 mandatory seat belt wearing was introduced in Ireland; in addition, there were serious fuel shortages and the interurban speed limit was reduced from 60 mph to 55 mph. In the second half of 1978 the blood alcohol limits had been reduced and there was an associated drink drive campaign (Mulkeen 1982). Any or all of these measures might be expected to bring about a reduction in road deaths. Clearly it could be expected that 1979 would become a land mark year in the history of Irish Road safety;

So what were the actual results? There are two standard reports available on this issue, RS 255 "The initial impact of seat belt legislation in Ireland" (Hearne 1981) and RS 408 "Seat belt wearing rates in Ireland" (Golden 1991). Writing in 1981, Hearne found that seat belt wearing rates in Ireland had gone from one in four, to one in two in the space of eleven months. So according to our model, deaths among the target group should have gone down by anything up to 15%.

However, Hearne reports that "the legislation has had no significant effect in the period considered on the severity of driver injury."

If we look at the actual crash figures then a slightly different picture emerges. There were increases in fatalities to both pedestrians and car users in 1979. Car user fatalities went up by 4% from 248 to 258 while pedestrian fatalities went up by one from 226 to 227 (Road Accident Facts 1982).

According to the tables given by Golden, there were 570 fewer injury/fatality crashes involving motor vehicles recorded in 1979 compared with 1978, so the fatality rate for car users per recorded injury accident actually went up. Hearne himself notes that "the number of drivers killed in single car crashes was higher than had been expected". Single car crashes are almost universally associated with inappropriate speed; that they should have increased in severity in a country that had just reduced the general speed limit is somewhat perplexing.

So in Ireland in 1979, deaths among cars users should have dropped by upto 15% but went up by 4%.

Something happened among car drivers that overwhelmed and overtook the protective effect of reduced speed limits, drink drive legislation and seatbelt wearing.


What might that have been?

One of the common sense arguments is that if you make people feel safer doing something that is risky they respond by taking more risks.

Sources

• Golden J.M., RS 408 "Seat belt wearing rates in Ireland" Environmental Research Unit, Dublin, 1991
• Hearne R., RS 255 "The initial impact of seat belt legislation in Ireland" An Foras Forbatha, Dublin, 1981
• Mulkeen E. Technical Digests Series, 12-Road Transportation and Safety, An Foras Forbatha, Dublin, 1981
• Road Accident Facts 1982

Right you seem to be missing the picture here, you are taking 1979 to 1980 as one year in isolation. This is a bad error on your part. It's a classic case of someone trying to look for bad analysis in data to try and prove a point by ignoring the obvious bigger picture.

Take the period 1978 to 1985, you have a 200 person per year decrease in the number of road deaths. This is off the RSA website, which doesn't break down betwen the types of deaths, but theres no reason to assume the percentages are massively different between 1978 and 1985. Not all of these are attributable to seat belts, but the timing is hardly a coincidence.



Lets look at the article you have quoted, there were 570 fewer crashed involving injury from 1978 to 1979, versus what overall numbers?

Thats a very large decrease, what caused this decrease, were their just less crashes, randomly? or were their less injuries due to the wearing of seat belts. I doubt there was any marked difference to 1978 as the death figures decrease at a steady pace. Yet the quoted article still makes a claim that it had no effect on the severity of injury, what about the 570 less total then?


Yer argument is that advances in safety cause people to take more risks, but the facts and figures clearly point that any risk is clearly outweighed by the introduction of these safety features, with a reduction to 250 from 640 in the last 30 years.

This is in the face of an increasing number of cars on the road.

If you mess up seatbelts, abs, air bags still clearly have a better statistical chance of catching you than if they aren't there.

Otherwise the safest bet would to ride around in an open cockpit scared of your life.

galwaycyclist wrote: »

I believe that the more existing cyclists who set a good example by cycling without helmets then the more non-cyclists might be tempted to take it up. At the moment the idea that you have to wear unusual and unattractive clothing is a barrier to cycling participation. Particularly among key sectors such as women and teenage girls.

I tend to agree with the idea that making "odd" clothing and kit look necessary for cycling acts as a deterrent to people who don't cycle but might consider doing so. However, I think that when you talk of people setting a "good example" by cycling without helmets it suggests that you've lost the argument of trying to convince people that helmets are not necessary.

I believe the arguments in favour of not wearing a helmet are strong, they are certainly strong enough to give someone plenty of food for thought. If a person considers those arguments but decides to wear a helmet anyway, then that's fine, that's entirely their choice (that describes me, for one). When you try to bend people to your own will by asking that they not wear a helmet for fear (ironically) that it'll instil fear in others then you are going way beyond the remit of encouraging educated choice and are getting into the area of dictating to people. Effectively you are going to the extreme end of the scale and wrapping back round to join the "wear a helmet or die" brigade in their philosophy of "I can't convince you therefore I'll yell at you". That's an approach that'll likely alienate the people that you are trying to reach out to.

smacl wrote: »

Absolutely, but what this says to me is the array of anecdotal material demands some further investigation. At a guess, we'd see a couple of such anecdotes relating to a crash with a knock to the head and a "praise be to the helmet, it saved my life" line each month. Say we ignore whether or not the helmet helped them as we simply don't know, but accept that they came off their bike and had some degree of an impact to their head. Say we see 20 such posts per annum, out of a population of say 1000 contributing boardsie cyclists. (Picking numbers out of the air, for sure, but roughly the right order of magnitude). That gives us a 2% probability of such an event happening to any given cyclist, in any given year. Small, but significant.

There are a few problems I can think of with such an approach. Are people posting on Boards typical of general population of cyclists, or are the number among them a disproportionate number of the type of cyclists who push themselves hard to improve on their previous best? Do they feature more mountain bikers than the general population? A 2% probability of incurring a head impact in any given year is higher than I'd expect for a cyclist who mostly cycles to the shops and back, but seems more credible for a competitive or off-road cyclist.

And should we not also look into neck injuries and compare how those who fall wearing a helmet compare with those who fall without wearing one? Or compare the rate of diffuse axonal injuries (generally due to rotational injury) to injuries more typical of linear impact?

I think the general strategy to take when anecdotal evidence suggests a trend is to devise an experiment to test whether the trend is real, or to look in independently gathered data (e.g. census data, traffic count data, hospital admission data) and look for the trend there. In-depth analysis of anecdotal data is not usually very rewarding.

So I think the two best approaches employed so far, and the two sources generally drawn on are the case-control studies (generally based on hospital-admission data and such like) and the trend in head-injury rates in jurisdictions with rising helmet use, comparing the cyclist trend with the trend for other road users.

The problem is that these two sources give very different pictures, which is part of the reason these helmet threads tend to go on a bit.

monument wrote:

How on earth is what you quoted him saying even close to dictating to people?

Providing people with information on both sides of the helmet argument and leaving them to make up their own mind on whether to wear a helmet or not is encouraging reasoning and the making of educated choices.

Trying to convince people via the argument "you don't need a helmet because look at all those other cyclists over there who don't wear a helmet" is trying to bend people to your point of view via peer pressure. That, to me, is dictating to people, though I could think of worse things to call it, what would you call it?

And trying to guilt people into not wearing a helmet because you believe not wearing one sets "a good example" is, amongst other things, extremely patronising.

monument wrote:

Such a view is influenced by your thinking on helmets.

That cuts both ways.

monument wrote: »

If you hit your head and a helmet cracked it means the force was greater than what the helmet is able to take -- so there's a risk of brain damage and you should have went to a doctor or straight to A&E regardless of how it looked.

Thankfully cyclists are the least likely road users to obtain serious brain injury and the least likely to sustain permanent brain damage.

In any case... Sounds like better and cheaper interventions would be to (a) slow down where needed, or generally if needed, and (b) not to lean over too far.

Is it possable you would have been going slower and taking less risks if you were not wearing a helmet?

My accident was totally my own fault, have been off the bike for 6 weeks injured (Knee injury not from a crash) and if honest was just enjoying being back on the bike, made a stupid simple mistake when cornering. I hit the ground hard with front of helmet, brushed myself down and cycled on to work. I work as a paramedic so the last place in the world i wanted to go to that morning was A&E. Between myself and a colleague I got checked over, I'd live to see another day. Would I take less risk without a helmet, I don't know, as I always wear one. The risks we take when decending, don't think a helmet would do much to protect you if it all went horribly wrong yet we all still love the trill of a fast decent.

Personally, I know of 2 people who had accidents and only for their helmets they are alive - both required work on their faces but there is no question that they would have smashed their skull if they hadn't got a helmet on. Both helmets smashed on impact but that is how they are designed to disperse the force.

I also came off my bike once myself, I was only new to the clips and I got my foot stuck when I had to stop suddenly and ended up smacking the side of my head off the ground. I was able to dust myself off and get back on the bike. Without the helmet I reckon I would have been concussed and needed stitches.

For me, its not a question, as much as I hate wearing a helmet I will always wear one but if people don't want to wear one thats their decision, and it shouldn't be law in my opinion. I do however strongly urge you to consider the feelings of your family and friends though and think how they would feel if you died when it could have been prevented. I always think how my son would feel to grow up without a father because I felt a bit uncomfortable or thought I looked like a bit of a spoon wearing a helmet.

If you hit your head and a helmet cracked it means the force was greater than what the helmet is able to take

Just reading back, in college we had to design a helmet and we had to go into the ISO standards for such. Helmets are designed to crack or break on heavy impact as this is how they disperse the actual force of the impact. The inner lining acts as a buffer between your head and the force so anyone saying that helmets are useless and break too easily, well thats what they are supposed to do!

I do agree that if you have an accident in which your helmet gets broken you should see a doctor.

droidus wrote: »

It seems strange to me that you're focussing on the alleged fanaticism of some who question the usefulness of helmets,

Huh? "alleged fanaticism" are your words, not mine, so I'm giving them right back to you. Handle them carefully, they are kinda inflammatory when you combine them like that.

And if you'll take a moment to untwist your knickers you'll find that I've taken issue with both extremes of view in this thread, those that claim that helmets are necessary to save your life, and those that claim that an individual wearing a helmet is somehow detrimental to society.

droidus wrote:

There is, as you say 'guilting' going on here, and its clear which side is indulging in it.

Yes indeed, *both* sides. And while those opposing sides swing for each other they are embroiling people with moderate views in their pointless battle and detracting from any useful debate in the process. The majority of us will continue to make up our own minds and could do without being lectured at by either of the views at the extreme ends of the scale.

doozerie wrote: »

Huh? "alleged fanaticism" are your words, not mine, so I'm giving them right back to you. Handle them carefully, they are kinda inflammatory when you combine them like that.

And if you'll take a moment to untwist your knickers you'll find that I've taken issue with both extremes of view in this thread, those that claim that helmets are necessary to save your life, and those that claim that an individual wearing a helmet is somehow detrimental to society.

Hmmm... OK, Well, Ive read all of your posts, and whilst most are measured and I agree with the vast majority of your points, Ive only seen you accuse one 'side' as trying to 'guilt' people into a particular viewpoint, and even if that were true, the level of moral blackmail is so egregious on the pro-helmet side it seems, as I said, strange to highlight a far less extreme example (Im not even sure it exists TBH) on the other side.

Yes indeed, *both* sides. And while those opposing sides swing for each other they are embroiling people with moderate views in their pointless battle and detracting from any useful debate in the process. The majority of us will continue to make up our own minds and could do without being lectured at by either of the views at the extreme ends of the scale.

Ah, so this is the 'grey fallacy' I've heard so much about:

An individual demonstrating this false compromise fallacy implies that the positions being considered represent extremes of a continuum of opinions, and that such extremes are always wrong, and the middle ground is always correct.

And, btw, apologies if I give the impression Im having a go at you personally, I was just a bit surprised that such a normally even handed poster would start picking so aggressively at a speck in one eye when there's a bloody great beam in the other.

(PS: I dont wear knickers.)

droidus wrote: »

Ah, so this is the 'grey fallacy' I've heard so much about:

No, not in my view. My personal view is that neither the pro- nor anti- helmet groups have proved their argument. I think that bicycle helmets are one of those things where there is no right or wrong choice, as such, so right now I don't see that there is an argument to win - there are a lot of anecdotes (which I don't value much in this context), quite a few scientific studies (some of them very questionable), and many opinion pieces (some of which are extremely biased), all of which amount to an argument which is not very convincing on either side.

Amongst all of that though there is a lot of useful information which can serve to guide someone as they evaluate whether, for them, a helmet is of any use. And I personally don't feel that I could criticise someone for their choice, whether that is to wear a helmet or not. Discussing the reasons for their decision, and questioning the veracity of some of the information on which they based their decision, is fine in my view, that's where debate comes in. Criticising their choice simply because it differs from mine is what I have a problem with and that approach is adopted by those with extreme views at either end of the scale.

As to the imbalance of numbers between those of the extreme views, yes I think there is an imbalance there. For every person who sees a helmet as some kind of despicable thing I expect there are many many more people who'll argue that a helmet will save your life and will try to back this up with some meaningless anecdote that is supposed to pluck at your heart strings. The latter group tend to be more vocal too so overall they tend to be more annoying and I am more inclined to simply ignore them.

I criticised that latter group in an earlier post when I moaned about the "it's only common sense" argument (an approach that seems to be considered some kind of acceptable face to the "wear a helmet or die" view) but to be honest I have no interest in challenging each of them in turn. To me, theirs is a religious view, they endow the helmet with some sort of miraculous powers that contradicts a lot of the scientific evidence (and, ironically, defies common sense too) and views like that tend to get more entrenched when challenged. But I'd hope that a meaningful debate that they cast an eye over might encourage them to think twice about some of their assumptions. But such a debates gets very quickly undermined when those at the other end of the scale start to argue that you are safer without a helmet - I believe that is actually true in some circumstances but when it is generalised then it becomes a bit of a religious argument in its own right and loses all value as a result.

If I'm targeting the "wear a helmet *and* die" argument at the moment (or what is considered its acceptable/moderate face), then it's because I want the actual debate to continue and not simply grind to a halt while the two side just butt heads. It's not because I consider the extreme anti-helmet argument to be worse than the extreme pro-helmet argument, they are as bad as each other in my view.