The helmet debate rumbles on in the mainstream media

that condition imposed on them by insurance companies.

RoadCC forum members have done some enquiring on this and they found it was a crock pushed by the organisers who were blindly following poorly carried out risk assessment recommendations.

I have no problem with recommended use of helmets where the risk assessing has been competently completed. It is similar to office fit-out jobs where everyone wears hi-viz and they are on the second floor and no-one interacts with vehicles or is working at a height where visibility of other trades could be compromised.

Well, I’ve enjoyed reading this thread.

I always wear a helmet these days. Despite never owning one until my late 20s I’m now of the opinion that the day I don’t put it on will be the day I clobber myself. I’m a little bit OCD like that.

Gotta agree here,
I can’t NOT get on a bike even witout a minimum of protection which for me is a DJ pot and gloves… if I’m going for a proper ride then it’s full face, and knee/shin armour. Call it OCD.

Had a mate who was riding back to Peebles from GT after sessioning the FR park, swapped his full face for a std helmet for the ride back, got 300yrds from his house dropped off a kerb and his wheel collapsed by the time the wheel fully disintegrated and he twigged what was happening he was 3/4 of the way across the road he was in a prefect position to launch his face into the opposite kerb as his forks dug in, cue smashed cheekbone, fractured jaw & nose and a LOT of bruising. He always said that IF he had kept his full face on he would not have suffered those injuries. OK fluke accident but I would far rather have a pot on than not and take my chances

I don’t care about being called a pussy for wearing all the protection I do, even for the most innocuous ride as you never know what is going to happen.

As for legistating helmet wear then for me if you are at a pukka trail center then it should be compulsory otherwise personal choice.

whilst I always wear a helmet for offroad and road riding – often i don’t for commuting…

so nice sometime to ride in civvies and without a helmet… makes you feel like a person who is just using a bike rather than a ‘cyclist’

The evidence that this is the case is far more compelling than the evidence that helmets will do you any good in a crash.

If you mean the experiment conducted by Dr Ian Walker, you are obviously easily compelled.

Feel free to educate me

One bloke riding a bike fitted with a measuring device riding up & down the same bit of road wearing either a helmet, no helmet, or a long blonde wig…..

All the Walker study is is an interesting indicative discussion piece. NO more than that. Fails all the standards just about for rigour and reliability. He doesn’t claim any more than that for it

However it is an interesting piece and consistent and may explain part of the answer as to why the protective effect predicted for helmets is hard to see in whole population studies.

Fair enough. However, since everyone else is presenting their anecdotes as evidence I feel it’s only fair if I’m allowed to do the same.

I remember getting into an argument in a pub once with some ignorant ****. What he was saying was that it was ok to hit cyclists if they were being annoying since “they’re wearing helmets”.

So the Cohrane review is bobbins but we can draw conclusion from a report you admit

Fails all the standards just about for rigour and reliability.

where the author has misled but now does not

He doesn’t claim any more than that for it

You seem to be using odd scientific standards here.

Junkyard – thats not what I said.

The cochrane review is badly flawed. it claims to be gold standard but falls far short for a whole variety of reasons. explained ad nauseum

The walker piece is an interesting discussion piece, the author clearly states it limitations in the paper he wrote and all I said of it was

and may explain part of the answer

I did not say you can draw conclusions from it.

😕 how can it answer part of it if you dont draw any conclusion from it? If it partially answers you have still drawn a conclusion from it. i dont see how we can debate that point tbh.

A criticism accepted by you and no one of scientific rigour – you could write to them they are very open – give it a go and feed back to us.

Basically when research disagrees with you you disregard it for bias, poor data and disregard it.
When it offers evidence to support or illuminate your case , even when you accept it is poor data and the author has misled you are still happy to have it as answering “some” questions.

If you wish to disregard the internationally recognised meta analysis WHO recognised NGO panel member for poor research then it would be credible and consistent to reject the later for the same reasons.
TBH it makes no sense to do this and it is not applying a universal standard to all research as far as I can see.

No junkyard – thats not what I have said or done.

I look at the data and its methodology and make my mind up about its validity. the walker piece is an interesting discussion point only – thats all its author claims it to be

have you actually read the cochrane review and the papers it relies on? I have. I did link to one critique of it for you. Critiques have been presented to the publishers and some of it accepted

I am doing this from memory so hopefully I have it right

1) of the 7 papers analysed 4 are written by the authors of the review. clearly they are not going to criticize their own work. they unquestioning accept teh varacity of the papers despite obvious flaws

2) all of the papers suffer the same basic flaw – a self selecting data set that is only a part of the population under study. it is assumed that the rest of the population is the same despite clear research from other places that shows it is not. this is a clear and major flaw. A study with a self selecting sample has built in bias. They only have in the study people who cycle and have injuries. As they do not even consider those who cycle and do not have injuries it is impossible to draw the conclusions they do. They assume that the part of the population they are studying is indicative of the whole population despite peer reviewed evidence that this is false

3) one of the papers is about children – and the results are extrapolated to adults despite again good evidence that children and adults behave in differnt ways.

4) Major assumptions are made without any evidence -firstly any risk compensation is simply denied, secondly any helmet exacerbated or induced injuries are denied. thirdly the fact that you are more likely to hit your head with a helmet on is denied ( your head is bigger and heavier)

5) there are some technical flaws in the calculations that I don’t fully understand but that have been pointed out by a professor of staistics

What these flaws do is mean the validity of the review is put into serious doubt

So – we have a flawed set of studies that predict an 80% protection effect from helmets. we have other studies ( with their own flaws) that do not show this effect. whats the sensible position? that the true effect is somewhere in-between

Junkyard – Member

how can it answer part of it if you don’t draw any conclusion from it? I don’t say that. Please read what I write – I selected my words carefully

and may explain part of the answer

ie its an interesting piece that indicates areas for further research and discussion.

Here is one detailed critique again. again as I have oft said take your healthy scepticism with you to this site

http://www.cyclehelmets.org/1243.html

and a peer reviewed critique of some of it

http://www.sciencedirect.com/science/article/pii/S000145751100008X

also this commentry is interesting

http://www.cyclehelmets.org/1207.html?NKey=57

Almost all cycling fatalities involve motor vehicles. A half inch of polystyrene will not help when a two ton vehicle hits you. Helmet or no helmet is a side issue.

As for head injuries in general they are mostly from falls and assaults (77%) and mostly alcohol related (61%) cycling is actually pretty safe and discouraging it with helmet laws or rules for organised rides is a bad idea..

http://www.bmj.com/highwire/filestream/358818/field_highwire_article_pdf/0.pdf

And again the CTC reviews

http://www.ctc.org.uk/resources/Campaigns/Cycle-helmets_brf.pdf

http://www.ctc.org.uk/resources/Campaigns/Cycle-helmets-%28the-evidence%29_brf.pdf

There is no justification for helmet laws or promotional campaigns that portray cycling as a
particularly ‘dangerous’ activity; or that make unfounded claims about the effectiveness of
helmets. Cycling has very substantial health and other benefits, whereas the risks of cycling
are not especially high. By reducing cycle use even slightly, helmet laws or promotion
campaigns are almost bound to cause a significant net disbenefit to public health, regardless of
the effectiveness or otherwise of helmets.
• The effectiveness of helmets is in any case far from clear. They are (and can only be) designed
to withstand minor knocks and falls, not serious traffic collisions. Some evidence suggests they
may increase the risk of cyclists having falls or collisions in the first place, or suffering neck
injuries. Whilst helmet laws have reduced cyclists’ injury numbers, the evidence suggests this
is wholly or mainly due to reductions in cycle use, not improvements in safety for the cyclists
who remain. Reduced cycle use may itself explain why the remaining cyclists are more at risk,
due to the loss of the benefits they previously gained from ‘safety in numbers’.

1) of the 7 papers analysed 4 are written by the authors of the review. clearly they are not going to criticize their own work. they unquestioning accept teh varacity of the papers despite obvious flaws

You would need to say what the obvious flaws in their research are other than the fact they wrote them. They could of course have written the peer reviewed reports and it is in fact actually good research and they are good researchers. Perhaps they know how to conduct research well enough for the wider scientific and health community if not to your high[er] standards.
They don’t aceept unquestioningly they clearly explain their criteria for selection -you are misrepresenting what they have done.

2) all of the papers suffer the same basic flaw – a self selecting data set that is only a part of the population under study. it is assumed that the rest of the population is the same despite clear research from other places that shows it is not. this is a clear and major flaw. A study with a self selecting sample has built in bias. They only have in the study people who cycle and have injuries. As they do not even consider those who cycle and do not have injuries it is impossible to draw the conclusions they do. They assume that the part of the population they are studying is indicative of the whole population despite peer reviewed evidence that this is false

So in order to work out if a helmet offers any protection in a crash we need to make sure we include cyclists who have not had a crash or else the research is fundamentally flawed. 😯 How daft a suggestion or complaint is that? it makes no sense to include and you cannot anyway. There is no way to include this data for it is not data. They are not injured so what can they tell us about whether a helmets protects you from injury?
They are not self selecting either.

To determine whether bicycle helmets reduce head, brain and facial injury for bicyclists of all ages involved in a bicycle crash or fall.

That is what they did why would they need to look at non crashers ?

3) one of the papers is about children – and the results are extrapolated to adults despite again good evidence that children and adults behave in differnt ways.

The research is about cyclists of all ages[see above] it would be remiss to not include children by any standard – you cannot seriously criticise an all age survey for including all ages and drawing conclusions about all ages. They have not extrapolated this to adults they have included it as part of the set termed “all ages”.
I am not sure you understand the research or science tbh given these last two points.

4) Major assumptions are made without any evidence -firstly any risk compensation is simply denied, secondly any helmet exacerbated or induced injuries are denied. thirdly the fact that you are more likely to hit your head with a helmet on is denied ( your head is bigger and heavier)

firstly it is about whether the helmet protects you when you crash – risk assessment is about whether you are more likely to crash if you wear one due to altered risk perception [probably some truth in that] . It does not alter the effectiveness of the helmet if you crash – yes they ignored it for obvious reasons. That is another question and it is worthy of study.
Secondly- if there were helmet induced injuries we would expect, on average [ or no significance for protection] to see the helmeted group to have more injuries than the non helmeted group. We don’t. *
Thirdly – Evidence of that claim re bigger head and again we would expect more on average [ or no significance for protection] injuries in the helmeted group than not and we don’t *

5) there are some technical flaws in the calculations that I don’t fully understand but that have been pointed out by a professor of staistics

ah right so you believe the bit you dont understand because it agrees with your view but you are not in a position to understand whether it is true or false and you cite an unnamed professor of statistics to supportt this view……is this meant to be persuasive? is this kind of science and detail the researchers should aim for ?
Some professor said some stuff about all the research you cited and the statistics are wrong but i did not understand why…convinced? Should anyone be?

*it is not inconceivable that in individual cases that helmets may exacerbate an injury as you claim. However on average it does not or we would have greater injury/no difference or non significance between helmet and non helmeted users. For example on odd occasions not wearing a seat belt may save your life in a crash by catapulting you out the car at high speed. It would not be reasonable to claim that seatbelts are not effective or that they injure folk [ in general] because of this. Research shows that wearing a seatbelt offers protection in general in the event of an accident as does the research for helmet wearing.

Junkyard – follow the links to the critiques. Explains it better than I can.

Infact here is the abstract from one published one

Publication bias and time-trend bias in meta-analysis of bicycle helmet efficacy: A re-analysis of Attewell, Glase and McFadden, 2001

Abstract

This paper shows that the meta-analysis of bicycle helmet efficacy reported by Attewell, Glase, and McFadden (Accident Analysis and Prevention 2001, 345–352) was influenced by publication bias and time-trend bias that was not controlled for. As a result, the analysis reported inflated estimates of the effects of bicycle helmets. This paper presents a re-analysis of the study. The re-analysis included: (1) detecting and adjusting for publication bias by means of the trim-and-fill method; (2) ensuring the inclusion of all published studies by means of continuity corrections of estimates of effect rely on zero counts; (3) detecting and trying to account for a time-trend bias in estimates of the effects of bicycle helmets; (4) updating the study by including recently published studies evaluating the effects of bicycle helmets. The re-analysis shows smaller safety benefits associated with the use of bicycle helmets than the original study.
Research highlights

? A meta-analysis of the effects of bicycle helmets published in Accident Analysis and Prevention in 2001 has been re-analysed. ? The re-analysis found that the original meta-analysis was influenced by publication bias and time trend bias it did not control for. ? When these sources of bias are controlled for, and new studies added to the analysis, the effects attributed to bicycle helmets become considerably smaller than originally reported. ? The findings of this meta-analysis are not consistent with a recently published Cochrane review.

Please – read the original papers, read the critiques with an open mind.

So in order to work out if a helmet offers any protection in a crash we need to make sure we include cyclists who have not had a crash or else the research is fundamentally flawed.

Yes indeed. Otherwise the helmets might be causing injuries or crashes – or the people crashing may not be representative of the whole population wich is etrapolated to.

without this data we do not know this

On stats

misleading Interpretation of Odds Ratios

As well as inadequate discussion of time series analyses and why little or no benefits have been found following helmet laws which required millions of cyclists in Australia to wear helmets, this Review appears to confuse odds ratios with the percentages of head injuries which might be prevented by helmets. This is a serious problem, potentially leading to significant errors of interpretation.

For example, imagine a hypothetical helmet which could prevent 50% of head injuries and a situation where 100 bareheaded cyclists had accidents, resulting in 40% of them suffering head injuries. Imagine a case-control study where 100 cyclists wearing this helmet had identical accidents to the 100 bareheaded cyclists. We would therefore expect on average 50% of 40 = 20 of these cyclists to suffer head injuries.

To calculate the odds ratio, we compute Odds(helmeted) = (No of helmeted with HI)/(No of helmeted without HI) and Odds(bareheaded) = (No of bareheaded with HI)/(No of bareheaded without HI)

The odds ratio is Odds(helmeted)/Odds(bareheaded) = 20/80 divided by 40/60 ie 0.375.

The authors of this Review have used this odds ratio interchangeably with the term “percentage reduction in head injuries” as if suggesting that odds of .375 means a 62.5% reduction in head injuries, not the 50% reduction it represented in this hypothetical example. Page 6 of this Review gives combined adjusted odds ratios from four of the studies of 0.31 for cyclists in bike/motor vehicle accidents and 0.32 for other crashes, which is translated, under the heading “Main results” into protection levels of 69% and 68%.

The fact that this can be confusing to other researchers is well illustrated by the first of the studies in the Cochrane Review. Thompson, Rivara and Thompson, 1989 found 17 out of 120 helmet wearers had head injury (14.2%), compared to 218/548 (39.8%) of non wearers. This leads to an estimate that helmets would prevent (1 – 14.2/39.8) = 64% of head injuries. The crude odds ratio was 0.25 and the adjusted odds ratio was 0.26. The summary of Thompson, Rivara and Thompson, 1989 did not present this figure, only the value obtained by comparison with the community control group of predominantly child cyclists who fell off their bikes. As already discussed, these children had an extraordinarilyhigh helmet wearing rate of 21.1%, compared to 3.2% in a stratified sample of 4501 children riding around Seattle but not falling off their bikes. The estimate, derived from the comparison with this exceptionally high helmet wearing group, was the only estimate of helmet efficacy presented in the summary of Thompson, Rivara and Thompson, 1989 “helmeted riders had an 85% reduction in their risk of head injury (odds ratio 0.15; CI 0.0-7 to 0.29)”

Sacks, Holmgreen, Smith and Sosin, 1991 interpreted the latter figures to mean that, out of 2985 head injury deaths to cyclists in the US over a 5 year period, up to 84% (2500) could be prevented if all cyclists wore helmets. An alternative estimate, based on the adjusted odds ratio of 0.26 was that 2148 (72% of total) could be prevented based. Again, Sacks, Holmgreen, Smith and Sosin, 1991 mistakenly believed that odds of 0.26 means that 74% of head injuries would be prevented, instead of the actual value of 63%, obtained by comparing injury rates in (potentially disparate) groups of helmeted and non- helmeted cyclists treated in the emergency room. In the Main Results section of their paper, Sacks, Holmgreen, Smith and Sosin, 1991 translated these figures into the claim that universal use of helmets by all bicyclists “could have prevented as many as 2500 deaths and 757 head injuries, ie one death every day and one head injury every 4 minutes.”

Well i tried to read this one
http://www.sciencedirect.com/science/article/pii/S000145751100008X
but i dont have $41 dollars could you send me your copy or a link that works because you have read it. Did you understand that stats this time?

As it was published in 2001 and the Cochrane report we are discussing* was published in 2009 I dont think it is actually a critique of the paper.

If this is what happens with an “open mind” I shall decline the invitation.

* hugors link http://www.thecochranelibrary.com/userfiles/ccoch/file/Safety_on_the_road/CD001855.pdf

edited – pointless.

Citation: Thompson DC, Rivara F, Thompson R. Helmets for preventing head and facial injuries in bicyclists. Cochrane Database of
Systematic Reviews 1999, Issue 4. Art. No.: CD001855. DOI: 10.1002/14651858.CD001855.

Published first in 1999

One more go

if we do not have the data on the whole population we do not know if the helmets are contributing to head injury. this is on reason why why the self selecting sample ( which is what it is) is a critical flaw

So in order to work out if a helmet offers any protection in a crash we need to make sure we include cyclists who have not had a crash or else the research is fundamentally flawed.
Yes indeed. Otherwise the helmets might be causing injuries or crashes – or the people crashing may not be representative of the whole population wich is etrapolated to.
without this data we do not know this

i cant decide whether to answer this or just chuckle.

Ok i have added all the data of all the people who did not crash and did not sustain an injury and now i am going to use it to see if a helemet protects you in a crash. I conclude I don’t know because I have no data to work with because they did not crash..there you go some free science fot your.

You cannot study people who don’t crash to see the effects of a helmet when you crash. How can anyone think that ?

Does it increase the risk or cause crashes is a different question- as i said in my critique of your critique and one the research never asked nor attempted to answer but the data selected did answer
To determine whether bicycle helmets reduce head, brain and facial injury for bicyclists of all ages involved in a bicycle crash or fall.
which is what they asked.

EDIT :answers the last post as well but you are confusing whether a helmet makes it more likely you will crash with whether it protects you when you crash. They are not the same question.

After the last crash my Mrs had I dug a lump of stone out of the side of her lid that was bigger than the end of my thumb. Without a lid I would have been taking her to hospital to have it removed from the side of her head. Wearing a helmet makes sense.

EDIT :answers the last post as well but you are confusing whether a helmet makes it more likely you will crash with whether it protects you when you crash. They are not the same question.

No I am not confusing these two things try actually reading waht I say

You fail to understand why the incomplete data set invalidates it – as above a part of the reason is HELMET CAN AND DO CAUSE CRASHES AND INJURIES AND MAKE IT MORE LIKELY YOU HIT YOUR HEAD. this is why yo need the rest of the population to control for this effect. without this dasts you cannot say helemts protect.

Junkyzard – you clearly have set out here with the view that helmets protect and you are going to prove me wrong. it would be much better if you looked at it with an open mind to attept to discover the truth

you continaully miss the point and distort what I say to score points.

Pleae – just read the studies and read the critiques.

Sorry my mistake then its actually two questions 😉
1.Do helmets make it more likely you will crash?
2. Does a helmet make it more likely you will hit your head when you crash?
Again they answered the question
To determine whether bicycle helmets reduce head, brain and facial injury for bicyclists of all ages involved in a bicycle crash or fall.

still not the same question from what i can see tbh unless you write
To determine whether bicycle helmets reduce head, brain and facial injury for bicyclists of all ages involved in a bicycle crash or fall.
its a different question. Why are we debating this? It is self evident

So different questions

FWIW it is possible that a helmet can both make it more likely you will crash and also protect your head when you do. Now this research proves the later and offers no evidence on the former but it was not designed to.

Junkyard – nope – you still don’t get it.

I am sorry I got into this debate. the Cochrane review proves nothing at all apart from people can find the results they are looking for. The methodological flaws are so great as to make the accuracy of the results highly suspect.

I’ve a job creation scheme – we’ll employ an Edinburgh resident to follow TJ around and push him off his bike at random points on every ride.
After a year we can do a statistical review of both his injuries and his blood pressure! 😛

The Cochrane Collaboration

Cochrane Reviews are systematic reviews of primary research in human health care and health policy, and are internationally recognised as the highest standard in evidence-based health care.

This seems to resurface pretty regularly and takes the same path each time. Shall we all agree to disagree and save the bandwidth 😉

I am sorry I got into this debate.

Bull’s droppings.

You’re like a moth to a flame.

Yes hugor – but this one is poor for a variety of reasons – a part of which is that its not a very suitable subject for the sort of collaboration. I do note you have refused point blank to answer difficult questions.

I ask you again.
1)If helmets give the high level of protection that this cochrane review claims why is this effect not seen in whole population studies?

2)Are yo happy that it is proven that helmet compulsion / promotion actually damage public health by reducing participation in cycling?

3) are yo in favour of compulsory drinking helmets or driving helmets – both of which would prevent far more deaths?

1)If helmets give the high level of protection that this cochrane review claims why is this effect not seen in whole population studies?

they are not mutually exclusive – not that i expect you to accept that – Type 1 – what happens when an individual crashes [ protects] what happens if everyone wears them -type 2- [bad more crashes] due to risk perception, driver distance to you, whatever. I am not suggesting the later is true but even if it is it does not disprove the question the cochrane report answers namely that it protects in type 1. I shall refrain from typing again.

2)Are yo happy that it is proven that helmet compulsion / promotion actually damage public health by reducing participation in cycling?

No are you – does this alter the efficacy of a helmet in protecting me if I crash? No

3) are yo in favour of compulsory drinking helmets or driving helmets – both of which would prevent far more deaths?

I am not in favour of compulsion for cycles nor for the incidents you site, I am heartened that you agree helmets would protect non cyclists if they wore them and would ask that you generalise that principle to cyclists.
You could of course argue it wont because the research is rubbish, we would be more risky and injure our heavy heads with the helmets getting rotational injuries, pass closer to each other in the street causing more danger and moan about the public health consequences of fewer people walking and our risks due to reduced participation. either would be consistent

Junkyard – stop making up things you claim I say. I have not ever said helmets do not protect at all – just that the protection is far less than advocates claim which is what the evidence actually says

I asked Hugor specifically because he is in favour of helmet compulsion. Helmet compulsion in the Uk would mean 200 more deaths each year.

Your analysis of point 1 is badly flawed as I have tried to point out to you but you are not listening.

Now Hugor – have you any answers to those 3 questions?

There are clearly too many differentiators and factors to apply to too many situations involving cyclists. When? Where? How fast? Why? When? How? Etc…..there will never be a correct answer to this. As a kid in ever wore a helmet, I pop to the shops I don’t wear one…yet I head out on the trails or trail centre and I automatically put my lid on. I have personally had two experiences where I was very pleased I was wearing my helmet…..it’s down to personal choice surely.

OK. Some things to think about.

1: The temperature in Australia is much highr than the UK. If the climate in Edinburgh was like Melbourne even I would think twice about putting on a helmet.
2: Helmet design has changed over the last 20 years, better ventliated (see above) & better looking. So people are more likely to wear them than in the 90’s
3: The advent of extreme sports (& the expansion on MTBing) means that there is less of a stigma in wearing helmets. Nobody thinks Danny Mac is a dork.
4: Changes in H&S over the last 20 years means that wearing a helmet is not as unusual as it used to be. It is interesting that one of the things the anti-hemeteers seem to fear is that kids will soon think that wearing helmet to ride a bike is ‘normal’ Heaven forfend…. wouldn’t it mean that the ‘anti-participation effect’ would disappear, surely a Good Thing, no?
5: The failure of population studies to show a fall in injury could, perhaps be due to the fact that while the safety conscious will wear helmets, those who are risk takers and get a thrill of ‘living on the edge’ are less likely to wear them – Risk compensation in reverse. Therefore those temperamentally most likely to have an accident are the least likely to wear protection.
6: As you probably know. Edinburgh has one of the highest rates of cycling in Scoland…it also has one of the highest helmet wearing rates in the country. So where is the correlation

Just a few ideas for you to mull over…

…it also has one of the highest helmet wearing rates in the country.

Any stats on helmet rates to support this?