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Stumps.
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September 22, 2016 at 8:45 am #26300
Eg3ftp1
**touch paper lit, retires rapidly**
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Stumps
Resorting to abusive name
Resorting to abusive name calling when you are made to look a fool nice one SP that’s really big and clever. 🙂HarryTrauts
felixcat]
felixcat wrote:The enduring popularity of helmets as a proposed major intervention for increased road safety may lie not in their direct benefits- which seem too modest to capture compared with other strategies- but more with the cultural, psychological and political aspects of popular debate around risk.I quote again the most relevant words from Spiegelhalter’s and Goldacre’s piece.
They say that the benefits are”too modest to capture”. This means that in their reading of all the studies they examined they could find no evidence of helmet efficacy. It is carefully expressed in the way scientists express themselves, but it is clearly saying that in all those studies, including those analysed by Olivier, there is no good evidence that helmets work.
Don’t you think that is a very clear rebuttal of Olivier’s 65% benefit?
harragan wrote:[quote=felixcat]They are saying that there is no evidence that helmets are any benefit.
Rather different to this study, isn’t it?
Goldacre and Spiegelhalter are recognised experts in assessing evidence of this sort.They don’t say that, at all. They do say there is a “contradictory mess of evidence,” though. And that there is “uncertainty about any benefit from helmet wearing or promotion…” You actually quoted this part!
I don’t care who wears a helmet or doesn’t. But don’t reinterpret evidence simply to justify your point of view. That is poor science.
Exactly. Too modest to capture is very different to no evidence. The evidence is contradictory rather than showing no evidence. They use their language carefully for a reason.
felixcat
The enduring popularity of
The enduring popularity of helmets as a proposed major intervention for increased road safety may lie not in their direct benefits- which seem too modest to capture compared with other strategies- but more with the cultural, psychological and political aspects of popular debate around risk.
I quote again the most relevant words from Spiegelhalter’s and Goldacre’s piece.
They say that the benefits are”too modest to capture”. This means that in their reading of all the studies they examined they could find no evidence of helmet efficacy. It is carefully expressed in the way scientists express themselves, but it is clearly saying that in all those studies, including those analysed by Olivier, there is no good evidence that helmets work.
Don’t you think that is a very clear rebuttal of Olivier’s 65% benefit?
harragan wrote:[quote=felixcat]They are saying that there is no evidence that helmets are any benefit.
Rather different to this study, isn’t it?
Goldacre and Spiegelhalter are recognised experts in assessing evidence of this sort.They don’t say that, at all. They do say there is a “contradictory mess of evidence,” though. And that there is “uncertainty about any benefit from helmet wearing or promotion…” You actually quoted this part!
I don’t care who wears a helmet or doesn’t. But don’t reinterpret evidence simply to justify your point of view. That is poor science.
felixcat wrote:They are saying that there is no evidence that helmets are any benefit.
Rather different to this study, isn’t it?
Goldacre and Spiegelhalter are recognised experts in assessing evidence of this sort.They don’t say that, at all. They do say there is a “contradictory mess of evidence,” though. And that there is “uncertainty about any benefit from helmet wearing or promotion…” You actually quoted this part!
I don’t care who wears a helmet or doesn’t. But don’t reinterpret evidence simply to justify your point of view. That is poor science.
NicholasM
felixcat wrote:Cycle helmets are useless, says brain surgeon
Leading neurosurgeon tells the Hay Festival cycling helmets are ‘too flimsy’ to be beneficial.I saw that article, but I think he was speaking from personal experience and obviously he wouldn’t encounter those who were uninjured as a result of wearing a helmet. Something he seems to have overlooked.
I had a quick look around for papers in the peer-reviewed literature and found several recent ones investigating the effctiveness of cycling helmets in reducing injury in the case of an accident. Two nice examples are given below. One is a sophisticated computer modelling exercise and the other is a practical experiment based on lab tests. Both come to supportive conclusions.
The practical study is:
“Bicycle helmets are highly effective at preventing head injury duringhead impact: Head-form accelerations and injury criteria forhelmeted and unhelmeted impacts”, Cripton, P. A., et al., Accident Analysis and Prevention 70 (2014) 1–7, doi: dx.doi.org/10.1016/j.aap.2014.02.016.
ABSTRACT – Cycling is a popular form of recreation and method of commuting with clear health benefits. However,cycling is not without risk. In Canada, cycling injuries are more common than in any other summer sport;and according to the US National Highway and Traffic Safety Administration, 52,000 cyclists were injured in the US in 2010. Head injuries account for approximately two-thirds of hospital admissions and three-quarters of fatal injuries among injured cyclists. In many jurisdictions and across all age levels, helmets have been adopted to mitigate risk of serious head injuries among cyclists and the majority of epidemio-logical literature suggests that helmets effectively reduce risk of injury. Critics have raised questions over the actual efficacy of helmets by pointing to weaknesses in existing helmet epidemiology including selection bias and lack of appropriate control for the type of impact sustained by the cyclist and the severity of the head impact. These criticisms demonstrate the difficulty in conducting epidemiology studies that will be regarded as definitive and the need for complementary biomechanical studies where confoundingfactors can be adequately controlled. In the bicycle helmet context, there is a paucity of biomechanical data comparing helmeted to unhelmeted head impacts and, to our knowledge, there is no data of this type available with contemporary helmets. In this research, our objective was to perform biomechanicaltesting of paired helmeted and unhelmeted head impacts using a validated anthropomorphic test head-form and a range of drop heights between 0.5 m and 3.0 m, while measuring headform acceleration andHead Injury Criterion (HIC). In the 2 m (6.3 m/s) drops, the middle of our drop height range, the helmet reduced peak accelerations from 824 g (unhelmeted) to 181 g (helmeted) and HIC was reduced from 9667(unhelmeted) to 1250 (helmeted). At realistic impact speeds of 5.4 m/s (1.5 m drop) and 6.3 m/s (2.0 mdrop), bicycle helmets changed the probability of severe brain injury from extremely likely (99.9% riskat both 5.4 and 6.3 m/s) to unlikely (9.3% and 30.6% risk at 1.5 m and 2.0 m drops respectively). These biomechanical results for acceleration and HIC, and the corresponding results for reduced risk of severe brain injury show that contemporary bicycle helmets are highly effective at reducing head injury metrics and the risk for severe brain injury in head impacts characteristic of bicycle crashes.
From their Conclusions –
“Bicycle helmets are effective at reducing peak translational acceleration and HIC values; parameters that have been correlated with risk of skull fracture and severe brain injury. For a 1.5 m helmeted drop, the risk of severe brain injury was reduced from 99.9%+ to 9.3%. Thus, for realistic impact speeds (Fahlstedt et al., 2012) bicycle helmets changed the probability of severe brain injury from verylikely to highly unlikely. A contemporary helmet can transform ahead impact that would result in severe brain injury (which in somecases could result in lasting disability) into an impact with little potential for skull fracture or severe brain injury.”
The modelling study is:
“A computational simulation study of the influence of helmet wearing on head injury risk in adult cyclists”. McNally, D. S., and S. Whitehead, Accident Analysis and Prevention 60 (2013) 15– 23, doi: dx.doi.org/10.1016/j.aap.2013.07.011
ABSTRACT – Evidence for the effectiveness of cycle helmets has relied either on simplified experiments or complex statistical analysis of patient cohorts or populations. This study directly assesses the effectiveness of cycle helmets over a range of accident scenarios, from basic loss of control to vehicle impact, using computational modelling. Simulations were performed using dynamics modelling software (MADYMO) and models of a 50% Hybrid III dummy, a hybrid cross bicycle and a car. Loss of control was simulated by a sudden turn of the handlebars and striking a curb, side and rear-on impacts by a car were also simulated. Simulations were run over a representative range of cycle speeds (2.0–14.0 m s−1) and vehicle speeds (4.5–17.9 m s−1). Bicycle helmets were found to be effective in reducing the severity of head injuries sustained in common accidents. They reduced the risk of an AIS > 3 injury, in cases with head impacts, by an average of 40%. In accidents that would cause up to moderate (AIS = 2) injuries to a non-helmeted rider, helmets eliminated the risk of injury. Helmets were also found to be effective in preventing fatal head injuries in some instances. The effectiveness of helmets was demonstrated over the entire range of cycle speeds studied, up to and including 14 m s−1. There was no evidence that helmet wearing increased the risk of neck injury, indeed helmets were found to be protective of neck injuries in many cases. Similarly, helmets were found to offer an increase in protection even when an increase in cycle speed due to risk compensation was taken into consideration.
From their Conclusions –
“There is a commonly held misunderstanding (CTC, 2012) that because helmets are tested at 6.2 m s−1 (13.9 miles per hour) they are ineffective above this speed. Our results demonstrate that cycle helmets are effective at cycle speeds of 14 m s−1. Similarly, it is often believed that, in collisions with vehicles at speeds in excess of 8.9 m s−1, helmets will not offer protection. Our results show that the impact with the vehicle (at speeds up to 17.9 m s−1) does not result in a serious head injury, because of the way the cyclist is thrown over the front of the car. Unlike a pedestrian impact, the cyclist is not accelerated to the speed of the car by the impact. The serious head injuries, in these accidents, result from impact with the ground after a fall from height during the throw phase.
In all cases the risk and severity of neck injury was lower than the head injury. Indeed in the majority of cases helmet wearing was found to be protective in terms of neck injury. There is therefore no evidence that helmet wearing increases the risk of neck injury.”
…which I thought was interesting.
(Any formatting errors are mine from copy and paste.)
It’s certainly possible to argue that the odds of having a serious cycling accident are so low that it is not worth the bother of wearing a helmet, or that discouraging cycling by mandating helmet use will kill more people through poor health than are saved by wearing helmets. But studies like the two above suggest that it’s no longer possible to argue the cycle helmets are ineffective.
ClubSmed
davel wrote:
davel wrote:As long as you’re pretty sure. That makes it science.Wasn’t trying to pass my experience off as science. I was just sharing my experience of what happened in one instance with very specific factors.
In my scenario I believe (note that word believe, not know) that the damage to my ribs and his head was lessened because he was wearing a helmet. I also believe (note that word again) that because of his choice of helmet (with visor/lens) he suffered other injuries that he would otherwise have not.
Stumps
In relation to the comments
In relation to the comments made about Curnow and the statistics he came up with, all i can say is the well know phrase:
Lies, damn lies and statistics.
Wear one if you want, dont if you dont want to, its that simple. Dont try and force people to change by spouting so called facts and figures – that goes for both sides.
Speaking from a purely personal perspective, i’ve seen and dealt with more than enough RTC’s over the years and it never ceases to amaze me the mess the ground makes when it comes into contact with a head after someone comes off a bike, but its your choice and i hope it will always remain that way.
psling
ClubSmed wrote:His helmeted head impacted with my chest at what I assume would be about a 30mph collision if he was travelling at the same speed. I came away with badly bruised ribs and he went to hospital with concussion (he lost consciousness twice before the ambulance took). I am pretty sure that both of our injuries would have been a lot more severe had he not been wearing a helmet.Although of course it’s possible you may not have been so badly injured if it wasn’t a hard helmet hitting you in the chest and he may not have been so badly injured by your own admission, indeed his concussion may have been as a result of wearing a helmet in this instance.
So, you can’t really be “pretty sure”, can you.
davel
As long as you’re pretty sure
As long as you’re pretty sure. That makes it science.ClubSmed
Here is my experience of
Here is my experience of wearing a helmet.
I was heading along the canal to where the road goes over it, this involves the path narrowing and going under the bridge. Visibility of the path ahead is greatly reduced due to this and according to strava I was heading towards it at around 15mph. As I entered the underneath of the bridge I encountered another cyclist at the last minute, coming towards me on the same side of the path (my left, his right) and tried to swerve to avoid him but failed.
His helmeted head impacted with my chest at what I assume would be about a 30mph collision if he was travelling at the same speed. I came away with badly bruised ribs and he went to hospital with concussion (he lost consciousness twice before the ambulance took). I am pretty sure that both of our injuries would have been a lot more severe had he not been wearing a helmet.
Though as an aside, his helmet was one that has an attached visor/lens and this shattered on impact badly cutting his face very near to his eyes requiring stitches so might be worth considering good old cycling glasses instead?Cycle helmets are useless,
Cycle helmets are useless, says brain surgeon
Leading neurosurgeon tells the Hay Festival cycling helmets are ‘too flimsy’ to be beneficial.When NZ made helmets
When NZ made helmets compulsory the number of riders went down from 250,000 to 150,00, but the injury rate nearly doubled.
Look at this graph and then tell me helmets would save 65% of head injuries.https://rdrf.org.uk/2013/12/17/the-effects-of-new-zealands-cycle-helmet-law/
When helmets were mandated in Australia wearing rates went up from about a third to nearly 100%. The head injury rate went up slightly.
You can find all the evidence in cyclehelmets.org.
Two scientists whose jobs are
Two scientists whose jobs are assessing statistical evidence for public health interventions and public risks have looked at all the evidence for the efficacy of helmets.
Ben Goldacre, Wellcome research fellow in epidemiology, and David Spiegelhalter, Winton professor for the public understanding of risk, looked for evidence that helmets work. They concluded that it could not be shown that they do. This is what they published in an editorial in the British Medical Journal.
In any case, the current uncertainty about any benefits from helmet promotion or wearing is unlikely to be reduced by further research. Equally, we can be certain that helmets will continue to be debated, and at length. The enduring popularity of helmets as a proposed major intervention for increased road safety may lie not in their direct benefits- which seem too modest to capture compared with other strategies- but more with the cultural, psychological and political aspects of popular debate around risk.
They are saying that there is no evidence that helmets are any benefit.
Rather different to this study, isn’t it?
Goldacre and Spiegelhalter are recognised experts in assessing evidence of this sort.Olivier and his department have form in poor quality work trying to support helmets. Several of the studies that they include in this meta-analysis are notoriously shoddy.
Leviathan
Can we just leave this for
Can we just leave this for now, no more bumps. Start a new thread when something happens, ay?
rjfrussell
There are obviously all sorts
There are obviously all sorts of arguments that can be run in relation to helmets. I entirely accept that if hit by a lorry, or in a major off, or, indeed, in a minor off, my helmet will make no difference. I also accept that, on current evidence, there is at the very least a risk that mass helmet wearing leads to worse driving behaviour. I also very strongly believe that helmet wearing should not be compulsory, because making it compulsory will have a significant deleterious effect on the number of people who cycle (esp commute/ short journeys etc) and and that would be a very bad thing.
But, for me, it is very simple.
I can very easily see how a moments inattention, or the shock of a close pass, of a spot of ice, or hitting a pothole, or stick or any number of things might cause me to have a fairly low speed tumble off the bike. I can very easily see how as I fall to the ground my head might hit a hard hedge, or corner.
Such an impact would, to my mind, be very similar to that incurred by, say, dropping the edge of a brick onto my head, from a hight of, say, 2 or 3 feet. Of course, if the crash impact is harder, it might be 4 or 5 feet.
Would I rather have a brick dropped from, say, 3 feet, onto my naked head, or my helmeted head.
I’d go for the latter.
What are the odds of ever having a tumble where this happens? Probably vanishingly small.
Am I prepared to run those odds? No. (Unless it is a beautiful day, and I am riding on a cycle path or very quiet rodes at a very sedate pace, and taking in the beauty of the world.)
If someone else is, that is there choice, and I respect it entirely,
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